Final Report Project #26 Induction Heater For Melting Aluminum

Aalto University, School of Electrical Engineering
Automation and Electrical Engineering (AEE) Master's Programme

ELEC-E8004 Project work course
Year 2019
Final Report
Project #26
Induction Heater for Melting Aluminum
Date: 31.5.2019
Yuvin Kokuhennadige
Md Masum Billah
Joni-Markus Hietanen
Jaakko Lind
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Information page
Students
Yuvin Kokuhennadige
Md Masum Billah
Jaakko Lind
Project manager
Yuvin Kokuhennadige
Official Instructor
Dr. Floran Martin
Starting date
10.1.2019
Completion date
21.5.2019
Approval
The Instructor has accepted the final version of this document
Date: 31.5.2019
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Abstract
Our project was to build an efficient and safe heating device that could melt aluminum by
electromagnetic induction. The purpose of this device is to melt aluminum cans at collection points
when recycling. The heating element of our device is made of a graphite crucible and Litz wire,
while the power electronics are built to provide the necessary power that can maintain a steady state
temperature of more than 650℃ in the crucible. Induction from the Litz wire creates eddy currents
in the crucible in order to heat up aluminum over its melting point. This induction heater can also be
used for other applications of melting and heating materials within temperatures 650℃ and 900℃.
The development of the induction heating device included thermal analysis of the heating
element and circuit simulation of an inverter and a gate driver. These made us identify the necessary
parameters needed to operate our device efficiently and safely. The operating frequency of our
device was found to be 100 kHz. Therefore, the gate driver and the inverter were designed to work
at that frequency. We were able to successfully implement a 100 kHz gate driver; however, the H-
bridge was not operational at that frequency due to parasitic capacitance of the MOSFETs. The
heating element was implemented according to the analytical thermal model, but it was not tested
for successful operation due to the inverter not being able to deliver power to the Litz wire.
Further development of the inverter in our project to provide a high frequency output could
result in an operational device that melts aluminum. The analytical models and simulations
generated during this project were an important step towards building a successful induction heating
device that can melt aluminum cans in the collection stage of the recycling process.
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Table of Contents
Abstract ................................................................................................................................................ 3
Table of Contents ................................................................................................................................. 4
1. Introduction .................................................................................................................................. 5
2. Objective ...................................................................................................................................... 5
3. Project plan .................................................................................................................................. 5
4. Heating Element Design .............................................................................................................. 6
4.1. Frequency Selection ............................................................................................................. 6
4.2. Wire, Insulation and Crucible Selection .............................................................................. 7
4.3. Power Transmission ............................................................................................................. 8
4.4. Analytical Results ................................................................................................................ 9
5. Inverter Design ........................................................................................................................... 10
5.1. Power Electronics .............................................................................................................. 11
5.2. Gate drivers ........................................................................................................................ 11
5.3. Implementation .................................................................................................................. 14
6. Reflection of the Project ............................................................................................................ 17
6.1. Reaching objective ............................................................................................................. 17
6.2. Timetable ........................................................................................................................... 18
6.3. Risk analysis ...................................................................................................................... 19
6.4. Project Meetings ................................................................................................................ 19
6.5. Quality management .......................................................................................................... 20
7. Discussion and Conclusions....................................................................................................... 21
List of Appendices ............................................................................................................................. 22
References .......................................................................................................................................... 22
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1. Introduction
Nowadays, an efficient heating system is highly demandable due to the rapid growth in
industries. There are several heating techniques used in industry to perform heating tasks. One of
the most efficient, reliable and secure heating methods used to melt metal is induction heating.
Aluminum is a common metal used in variety of products in households or industries. Around the
world, large amounts of aluminum cans are produced every day. Recycling aluminum cans saves
energy, reduces environmental pollution and minimizes waste at landfills. Apart from that,
recycling aluminum cans is a large business with large market size. Therefore, a fast and efficient
heating system is highly demandable to make the recycling business more profitable.
The principle of induction heating is developed based on Faraday’s law of electromagnetic

induction. According to Faraday’s law, when an alternating current flow through a coil, it induces a
magnetic field around the coil. The density of the induced field depends on the number of turns of
the coil. The varying magnetic field induced by the coils flow through the metal workpiece and
produces eddy currents flowing through the workpiece. Energy is lost due to eddy currents and the
resistivity of the workpiece, which are dissipated as heat through the workpiece.
In induction heating systems, the higher concentrations of eddy current are preferred near
the surface of the workpiece rather than center. This phenomenon is known as the skin effect. High
frequency pushes the eddy currents to flow at the surface, hence, increasing the skin effect.
Furthermore, high skin effect increases the effective resistance of the workpiece and causes high
heat as needed to melt the workpiece.
2. Objective
Main objective of this project is to build a functional induction heater prototype, which is
capable of melting aluminum cans. Project hardware consists of four main components: a rectifier,
inverter, inductor and crucible. Rectifier and crucible have been bought as full industrial packages,
but inverter and inductor as well as their desired characteristics have been designed and built
independently. Output for desired current and therefore temperature should be precisely
controllable. Prototype should also be robust as well as easy and safe to use. Later the prototype
should be able to be productized to a saleable commodity, with constant option for further product
development.
The end-product can decrease volume of aluminum cans to enable more efficient shipping
or melt aluminum on junkyards to be sold as low-volume metal blocks. In the recycling business, it
would make aluminum recycling less expensive and energy-intensive. However, main objective is
that it will save our customers significant amount of money. Further developed end-product could
also be able to melt any desired metals with melting point below of around 1200°C, after further
thermodynamic calculations and implementations. In this case, our product could also be sold to
jewelry stores or manufacturers for easy “tabletop foundry device”.
3. Project plan
The project plan gives a relevant background and motivation for the whole project. In the
project plan the goal of the project and expected output are well defined. The electromagnetic
induction is explained and the needed system for the purpose is proposed and justified. The
introduction of the project plan was in terms with the project till the end, as the basic operation of
the project output remained unchanged during the project. However, some changes to the initial
plan were made during the project.
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The project plan has well defined and scheduled phases of the project. The definitions of the
project phases were relevant during the project with some changes done but the initial schedule for
the completion of each phase did not match the project plan. The phases of the project with updated
descriptions as well as the actual completion dates can be seen in the section 6.2 of this report. The
main delays happened in the conceptualization, prototyping as well as in the implementation
phases. The delays happened mainly because we needed to do some changes to our initial project
idea, and this slowed down the processes. Some delays also happened because of the component
deliveries.
The project plan had scheduled times for transformer implementation as well as design for a
cooling system for the coil. Later in the project, with the new project idea these components became
irrelevant as they were not needed in the system. The resources that were planned on these were
used for planning the implementation of the inductor made from Litz wire and the effect of graphite
crucible that was not initially planned on being in the system. In order to use these new
components, we needed to do more thermal modelling than initially planned.
Cost for this project was estimated in the project plan. The initial estimation for the whole
cost of the system was quite accurate. However, we needed to do some changes to the system in the
implementation phase, so the total cost was higher than planned. These costs were mainly due to the
changes of the power electronics.
The risk analysis of the project plan describes multiple justified risks for the whole project.
One of the biggest risks in our case was the design flaws in the project. Even with careful and well-
done simulation of the whole system circuit, we ran into a problem that we couldn’t tackle in the
system. The parasitic capacitances of the MOSFETs made our H-bridge not operational with the
used gate driver circuitry. Because of the high switching frequency of 100 kHz the system did not
work in the end. The designs of the circuits are explained in section 5 of this report.
4. Heating Element Design

The main objective of the heating element design was to generate sufficient temperature for
melting aluminum. The heating element consists of a graphite crucible, fiber glass wrap insulation
and Litz wire as shown in figure 1. A power supply with desired output current, voltage and
frequency were required to get the proper temperature. Therefore, the design specifications for the
power electronics were also determined in this section. Furthermore, the number of insulation layers
were calculated to protect the Litz wire from high temperature. Finally, a thermal model was
developed to ensure the temperature limit for the Litz wire and melting temperature for the
aluminum.
4.1. Frequency Selection

Alternating current (AC) flows through the skin or the surface of a conductor rather than
the center of a conductor. Therefore, the current density is larger near the skin or surface of the
conductor. This phenomenon so-called skin effect is used in induction heating systems. Higher
skin effect increases the effective resistance of the workpiece which leads to the resistive losses
of the workpiece, hence, producing high heat eventually melting the aluminum. The qualitative
measure of skin effect depends on the skin depth of the work piece and the frequency. At high
frequency, the skin depth becomes smaller, thus, the skin effect increases.
The required frequency of the current can be determined from the skin depth of an
aluminum can using the following equation
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2
" = $ (4.1)
&'(
where ( is the conductivity of aluminum, ω is the angular frequency and μ is the total
permeability of the material.
By solving the above equation, using the MATLAB script in Appendix 2, the switching
frequency was found to be 100 kHz.
4.2. Wire, Insulation and Crucible Selection

The design process of the induction coil started by considering a copper tube. Later the
copper tube was replaced by the Litz wire. Even though Litz wire is more expensive than a
copper tube, special characteristics of Litz wire met our design requirements. A Litz wire is a
special type of wire consists of multiple strands insulated from each other. This wire can carry
more alternating current (AC) current by minimizing the skin effect at high frequencies. As we
are using high frequency in our device, Litz wire is more suitable for our design compared to a
copper tube. In addition, Litz wire currents are distributed equally among multiple strands by
reducing the resistance and increasing the power transmission capability. The selected Litz wire
for our device has the specifications shown in the table 1.
Table 1. Litz wire specifications.
Wire diameter 0.5 mm
Number of strands 70
Strands diameter 0.056 mm
Wire length 19.5 m
Resistance 1.75 Ω
Inductance 32.8 µH
Maximum temperature limit 150 - 180 ℃
To protect the Litz wire from high temperatures, sufficient insulation is needed between
the crucible and the Litz wire. Fiberglass wrap was used as insulation because of its high
temperature resistant capability. The width and thickness of the used fiberglass wrap are 50 mm
and 1.1 mm, respectively. Maximum temperature limit of fiberglass wrap is 1200℃, which was
sufficient for our design. By verifying with the thermal model, a total of 19 layers of insulation
was used in our design.
The graphite crucible was used to hold the melting aluminum. We chose a graphite
crucible because of the high melting point of graphite; thus, it can withstand the high
temperatures. The specifications of the used graphite crucible are given in table 2.
Table 2. Graphite crucible specifications.

Inner diameter 46.19 mm
Outer diameter 70.57 mm
Height 113 mm
Maximum temperature limit 2500 ℃
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Figure 1. Final design of the induction heating element.
4.3. Power Transmission

Eddy currents are responsible for transmitting power to the graphite crucible. Therefore,
solving for the eddy currents was essential to calculate the transmitting power. As shown in
Appendix 1, the Maxwell equations were solved and the 1D analytic solution of the Bessel
function was used to find the eddy currents. The amount of power transmitted to the graphite
crucible was calculated using the following equation
∗
8888888
45667 . 48888888
5667
2(3) = (4.2)
2(
∗
where 48888888 8888888
5667 is the conjugate of 45667 and ( is the conductivity of the material. Current
through the inductor coil was estimated using Ampere’s law,
<; =
:; = (4.3)
>;
where <; is the magnetic field strength of the coil, L is the length of the wire and >; is the
number of turns. The MATLAB script in the Appendix 2 was used to calculate the transmitted
power and other parameters for the design are given in the following table.
Table 3. Design parameters and transmitted power.

Supply current 2.1 A
Required voltage 43.3 V
Number of turns 55
Total transmitted power 60.1 W
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4.4. Analytical Results
A thermal model of the heating element was developed to ensure that the temperature at
the Litz wire is within the specified limit while sufficient melting temperature is at the aluminum
can. The number of insulation layers required to save the Litz wire was determined by this
thermal analysis. As heat transfers from a higher temperature to a lower temperature, we
modeled that heat transfers from the aluminum can to the Litz wire. In this model, heat transfer
to the air (convection) is also taken into account.
Figure 2. Thermal model of the heating element.
The thermal resistance of the heating element in the radial direction is calculated using
the equation
3
ln ( E )
3F
@AB = (4.4)
2GHI
where 3E and 3F is the outer and inner diameter of the elements, H is the thermal conductivity of
the elements and I is the length of the elements. The thermal resistance due to convection is
calculated using the equation
1
@JKL = (4.5)
MN
where M is the convection coefficient and N is the cross sectional area.
The thermal model was solved analytically for three different temperature points, at the
Litz wire, at the graphite crucible and at the aluminum can. The MATLAB script in Appendix 3
was used to calculate the thermal resistances, convection resistances, losses in the elements and
the temperatures at different points. Analytical results of the temperatures at the three different
points are shown in table 4.
Table 4. Analytical results of the heating element.

Litz wire 78 ℃
Graphite crucible 921 ℃
Aluminum can 921 ℃
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From the analytical results, it is visible that the Litz wire temperature is within the
specified limit of 150℃ and the temperature at the aluminum can is sufficient to melt it. The
experimental results are not available as tests with the heating element was not conducted due to
issues with the power source which is explained in the next section.
5. Inverter Design
After calculating the desired output current amplitude and frequency, it was easier to define
the preliminary needs for our inverter, as it should be able to output 14 Amperes at 100 kHz
frequency to reach our target temperatures. Inverter consist of four power MOSFETs and their
control circuitry, the gate drivers. Power MOSFETs are connected in a H-bridge, with inductor as
its load (Figure 3). The H-bridge is the easiest way for supplying alternating current to the load,
which is needed for induction. Power electronics had rather low voltage requirements, as the need
current and switching frequency were high. The inverter is supplied with a rectifier, which was
purchased as a commercial package. It feeds the H-bridge with constant 48V voltage and maximum
20A of current.
Figure 3. Simplified schematic of the inverter design. MOSFETs are connected in an H-bridge with inductor
as a load. Resistor Rs represents inductor wire resistance.
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Figure 4. Simulated output current and output voltage fed to the inductor.
5.1. Power Electronics

For main power electronic components, we chose IXYS Polar3 HyperFET Power
MOSFETs (IXFH60N50P3), with current rating of 60A, voltage rating of 500V and power
dissipation of 1040W. This particular MOSFET was suitable, due to its high-power durability,
documented use of high switching frequency as well as availability and price. Also, current and
voltage ratings were adequate at least according to simulated values and all of their potential
transients.
5.2. Gate drivers

We designed and built our own gate drivers for supplying the power electronics.
Preliminary needs included sufficient and controllable fluctuating input current to the load, with
constant switching frequency of 100kHz. Values for frequency as well as current were calculated
by hand, and afterwards simulated with different simulation tools to ensure sufficient
temperature on the crucible and our workpiece. Output current is controlled by adjusting the
relative duty cycle of the gate pulses via a potentiometer, in order to reach the desirable
temperature at the crucible.
Figure 5. PLECS simulation of the gate drivers.

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Design of the gate driver starts with an oscillator. We chose a clock crystal oscillator
(OV-0100-C7) that derives 100 kHz output at 5 V amplitude, which was perfect for our
purposes. After this, the oscillating signal was divided into two. Second signal was delayed for
5µs to gain a perfect phase shift between the two gate signals of MOSFETs in the same leg.
Delay circuit we chose for this purpose was LTC6994-2. Next, the two square-wave signals were
transformed into triangular wave by adding a few capacitors and resistors. These triangular
waves function as our carrier signal for generating PWM.
In order to achieve the desired controllability, we chose to control the MOSFET gate
inputs manually, using a potentiometer and simple voltage division technique. Via the
potentiometer, we could increase and decrease a fixed DC-voltage value, which is compared to
the triangular waves using comparators (LM339). At the comparator outputs, we have two
convergent gate pulses with perfect constant delay compared to each other. These pulses were
then amplified with simple bipolar transistors (2N2907A) and fed to optocouplers (HCPL-4200),
in order to have the drivers galvanically isolated from the power electronics. Also, this method
gives us steady gate pulses with desired amplitude, which in this case was set to 15V.
Simulations are presented on figures 3 and 4. On the gate driver subsystem, oscillator and
transformation to triangular wave have been implemented on a simpler triangular wave block for
simplicity, but real circuit is presented on the schematic (Figure 5).
Major issues with this approach are that the gate pulses for upper and lower MOSFETs
can’t overlap, as a short circuit through them would quickly destroy the components. Other issue
to be considered is that the changes for supplying the components have to be fulfilled slowly
enough, since fast changes would result to high current and voltage transients, also capable of
burning our power electronics.
First issue was taken into account at the voltage division. We chose the resistor values in
such manner, that the minimum DC-level achievable by the resistance change with the
potentiometer would correspond to around 45% of pulses duty cycle. Therefore, the two pulses
would have enough switching time on maximum duty cycle conditions, and they would never
overlap. Also, if the DC-level would exceed the carrier triangular waves amplitude, comparator
would not give an output and gate pulses would be cut off (Figures 6 - 8).
Figure 6. Waveform of maximum achievable duty cycle. On the left are the two carrier signals, and on the
right the gate signals. Gate signals never overlap.
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Figure 7. Waveform of decreased duty cycle.
Figure 8. Waveform of lower duty cycle. As DC-reference (red on the left figure) is increased over the
carrier waves amplitude, gate pulses will stop.
Second issue can be solved by careful increase of pulse widths while testing the inverter.
Since the control is done manually, the individual lowering of the reference voltage should be
done so slowly and steadily until the desired condition has been reached. This prevents the most
destructive power surges from occurring. It is a crucial issue to be noted with such high
frequencies.
Simulations were carried out with Plecs and LTSpice-tools both for power electronics
and individual electronic circuits. It is notable, that all of the real-life phenomena considering the
switching of power electronics cannot be taken into account with these simulation tools at such
high frequencies.
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Figure 9. Schematic of the gate driver circuitry.
5.3. Implementation
Implementation of gate-driver circuitry was not as simple and straightforward as one
could expect. Especially the component selection and their configurations were at times really
difficult, since the switching frequency of 100kHz generates a lot of undesirable phenomena, and
most of the basic components are not made for such frequencies. Also, some of the components
were really small by size, so their connection was challenging in general. Debugging the
different phases of the previously described schematic was time consuming, but in the end the
gate drivers functioned nearly as they were specified. However, the inverter could not work with
the complete H-bridge, as discussed below.
After previously designed gate drivers were implemented (Figure 10), gate signals were
close to perfect. Amplitude, controllability and phase of the generated PWM worked perfectly.
In comparison for simulated gate signal values, measured values derived from an oscilloscope
are visible on figures 11 to 13. However, after connecting this gate driver to our power
electronics, the signal became heavily distorted and noisy.
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Figure 10. Implemented gate drivers on a circuit board.
Figure 11. Measured gate driver signals at their maximum duty cycle. On the upper part, one of the carrier
waves is visible alongside the controllable dc-value.
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Figure 12. Measured gate driver signals with lower duty cycle.
Figure 13. Measured gate driver signals with low duty cycle. If DC-value exceeds the amplitude of carrier
signal, pulses are stopped.
Distortion of the signal was caused by the parasitic capacitances of the chosen MOSFET
and was really significant due to high switching frequency. This issue was tackled with a
bootstrap-circuit with a transistor totem pole. Bootstrap circuit allows the operating point of the
transistor to be altered, by controlling the input impedance of an amplifier. Transistor totem pole
is used to control the ground level on our H-bridge, as on the upper MOSFETs, the source of the
transistor is not always connected to ground. With a totem pole, we are able to control the upper
MOSFETs with our signal, since the source is virtually grounded and the gate signal amplitude
between gate and source sufficient for our needs. Together they were implemented in order to
solve our issues caused by the parasitic capacitances.
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Figure 14. Schematic of the push-pull totem pole with a bootstrap, which was implemented after the
optocouplers on previous schematic (Figure 9).
Afterwards, the gate signals were significantly better than the distorted ones. With one
discrete MOSFET we were able to output current in sinusoidal form at amplitude of 2 Amps, but
with a full H-bridge we were not able to get good results. This current heated up the crucible a
bit but did not reach temperatures needed for melting aluminum.
6. Reflection of the Project

6.1. Reaching objective
The expected output of the project was not completed as we were not able to get our
power electronics working as designed. The expected output of the project was to melt aluminum
using electromagnetic induction. The goal was clearly not met because we were not able to
provide the induction coil with the needed current with our desired switching frequency. The
objective was to create two subsystems that would work together in the end. We were not able to
test the heating element subsystem as it was designed to work with the parameters provided by
our power electronics.
The simulations for the power electronics and heating element were created carefully.
The simulations were used to define the needed components for the subsystems. In the
simulations, the objective for the project was reached. The simulation results worked together
and the needed temperature for melting aluminum was reached. Even with these results, the final
system did not work. The reasoning for failures is described already in this report.
The objective was remained almost the same during the whole project, but the heating
element design was changed during the design phase of the project. It was thought that the water-
cooled copper induction coil would be hard to implement, so we decided to proceed the design
with Litz wire and graphite crucible with fiberglass insulation between these two components.
This suggestion was internal as we were discussing about the implementation of the cooling
system and came up with a better solution with the help of our instructor.
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6.2. Timetable
The overall project was realized as planned, however there were some delays in
conceptualization and prototyping phase as our design idea changed from the initial idea we
planned. Phases mentioned in the project plan were completed as shown below. It is noticeable
that there were some delays in meeting the deadlines planned. However, the overall project
deadlines were reviewed, and necessary precautions were taken when these delays occurred in
order to make sure it does not affect the overall project.
The workload of the project was as estimated, and we each spent about 200 hours on the
project. Most of our hours towards the project was invested in the last two weeks before the gala
as our subsystem completion and system integration did not go smoothly as planned and we had
to spend a lot of time debugging. Therefore, it is clear that we underestimated the workload for
those phases of the project when we allocated time in our project plan.
M1 Planning (Planned deadline: 4.2.2019, Completed on: 1.2.2019)

During this phase the project plan document was completed and was used as the basis for
conducting duties of the project.
M2 Conceptualization (Planned deadline: 18.2.2019, Completed on: 9.3.2019)
Conceptualization was delayed due to some changes that had to be made in order to
achieve our project goal. During conceptualization it was found that we would not be able
to build power electronics to provide the enormous power needed when using a copper
tube as the induction source. After finding this issue, a new concept was realized using litz
wire and a graphite crucible.
M3 Prototyping (Planned deadline: 18.3.2019, Completed on: 12.4.2019)
Prototyping was done using simulations for power electronics and using a theoretical
model for the thermal design of the crucible. There were delays in this phase as a ripple of
the delay in the previous phase as well as some additional delays caused by errors in our
models that needed correction.
M4 Subsystem completion (Planned deadline: 15.4.2019, Completed on: 18.5.2019)
The duration of this phase includes the time taken to place orders and delivery of needed
material. After collecting the parts, the assembly of independent subsystems were done
and then tested for their performance. Some issues with the subsystems were also realized
but had to move onto the next phase since we were approaching the final deadline.
M5 System integration (Planned deadline: 6.5.2019, Completed on: 20.5.2019)
Separately implemented subsystems were integrated in this phase to complete the system.
Testing was conducted to make sure the heating device operates as designed. However,
our system did not function as expected and caused major issues which we were not able
to resolve in the time available.
M6 Final delivery (Planned deadline: 20.5.2019, Completed on: 20.5.2019)
This phase was intended to demonstrate the working device to the instructor and to others
who are interested. Since our device did not function, we were able to deliver a model of
the device instead of a working prototype.
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M7 Presentation (Planned deadline: 21.5.2019, Completed on: 21.5.2019)
Poster presentation and highlight talk was done at the final gala to present our results and
findings the attendees. Even though our device did not operate, we displayed analytical
results and simulation results we obtained while designing the device.
M8 Project Report (Planned deadline: 31.5.2019, Completed on: 31.5.2019)
This project report was completed as planned by the deadline with the available results
from our project.
6.3. Risk analysis

Design flaws are one of the common risks that were visible during the project. Errors in
the models consumed a large amount of time to debug which slowed down the design process.
An alternative plan and a rapid solution minimized the severity of the risk. During the project,
few initial plans were changed which also affected the project timeline and delayed the process.
The risk was minimized by implementing the new plan effectively.
Another risk was also noticeable during the ordering and shipping of the components.
The order placement of the components took quite a long time which delayed the process. Also,
the shipping time of the components was different and some of the components took a longer
time than others. The risk was tackled by starting to implement with the components that arrived
first. Some of the components that were delivered did not meet the design specifications we
ordered or needed. Due to time constraints we had to adjust our project parameters and
dimensions to suffice the delivered components. In some occasions, we needed to reorder the
components or buy from a local store which exceeded the proposed project budget.
Health hazards were also realized during the implementation phase. To make the
insulation layers we needed to cut the fiberglass wrap. During that time, we felt unexpected
itching in our body because of the tiny glass components. The severity of this risk was quite low.
There could have been more risks associated in the testing phases such as aluminum oxide, paint
fumes and fire hazard. Since we were not able to test the design, those risks were not realized
during the project.
6.4. Project Meetings

With our instructor we had project meetings on average every other week. Meetings were
arranged in order to report our progress as well as to solve more advanced issues considering the
project development. Our instructor was very supportive during this process and capable of
solving quite complicated problems consistently in a manner, that supported the project works
learning objectives to us. Also, on the design phase of the project, he had fresh and diverse ideas
to tackle some of the development-related problems, resulting to better and more versatile end
product.
Among the group, we additionally met on average once a week to report our progress on
different segments of the project and discuss the arisen questions with each other. During these
meetings, our objective was to solve our issues together and keep track of the project status in
general. These meetings were documented and archived for later reference. In addition, as new
development proposals or issues were found, they were later carried out to instructor meetings.
This method of working helped the instructor meetings to be more efficient, and therefore
smoothed the whole development process.
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Archives of the meeting documents were stored on a common google drive folder, which
also included all of our documents considering design specifications, business aspects, technical
simulations and drafts of different reports. There, they were easy to reach if necessary.
In order to make project meetings more efficient, we learned in an early stage, that if
there was a more demanding or otherwise time-consuming issue at hand, it was not worth all of
our time to look as one person of the group tried to solve it. In these occasions, we usually
postponed the task to occur outside the meeting or tried to solve it in the group. If solution could
not be reached, then it was later brought up on the instruction meetings. Overall our efficiency
during these meetings was decent.
6.5. Quality management

In our project plan the management of quality was defined for the various parts of the
project. The main points were that every team member will do their tasks with best possible
quality. The basic idea was that the project manager is not fully responsible for the quality.
However, he was responsible for approval of each step of the project. For example, after a
document was done, the project manager was the one approving it so that it could be sent to the
instructor for final approval. In our project, the instructor was the one who did the final
approvals and gave feedback on our work.
The quality plan was followed well when creating the documentation for the project as
well as preparing for presentations. The quality of these deliveries has been approved by the
project manager and the documents were approved by the instructor as well. During the project,
the documentation has achieved high quality and the presentations have also been on satisfactory
level. The project manager has done a good job on supervising the quality of the team’s work.
In the integration phase the obvious quality issue was that the system did not work as
intended. Because of this issue, the wanted quality for the presentation was not achieved as we
were not able to show the functionality of the whole system. We couldn’t prevent these issues
even though the integration phase was planned well ahead.
There were some issues about the quality of the system. There were two main things that
would have improved the quality of the final system. During the planning phase, we did not
design a PCB and a case for our power electronics. A PCB and a case would be essential for the
gate driver circuitry and H-bridge as they have numerous connections that we needed to be cover
and secure. The case would have also made the product more professional looking. The second
quality issue was related to the graphite crucible in the heating element. We did not plan how the
molten aluminum would be taken out of the crucible easily. There could have been designed a
pouring mechanism that would help with the issue. Without this kind of mechanism, it was
decided that the aluminum would be taken out of the crucible when it was cooled down. With
these two improvements, the final product would have been safer and more user-friendly.
Page 20 of 22
7. Discussion and Conclusions
This project gave all members of the team a foundation in thermal modelling as we got to
learn analysis as well as solving a thermal model. We learnt this while calculating for the amount of
insulation needed in the heating element to assure thermal safety of the inductor when there are high
temperatures at the crucible. Finding thermal properties of the materials used and evaluating the
physical dimensions of the device were important aspects of the thermal analysis. Eddy currents in
the crucible was calculated using the 1D analytic solution of the Bessel function which was taught
to us by our instructor. This solution gave us an idea of how complex thermal analysis can be as
solving the Bessel function required very advanced knowledge in the field.
The largest challenge we faced as a team during this project was to implement the high
frequency dc-ac converter. Since the frequency of the alternating current needed at the inductor was
found to be 100 kHz using the skin depth equation for creating eddy currents in the aluminum can,
we faced with the objective of designing a high frequency inverter. The H-bridge of the inverter and
the 100 kHz gate driver was simulated to verify the operation of the design and after obtaining
successful results we moved to implement the circuit. Even though the gate driver was operational
as we expected from the simulation, the H-bridge wasn’t operational with our gate driver due to
parasitic capacitance of the MOSFETs. This was a good learning opportunity for us. It was found
that considering factors that may not be portrayed in simulations but could affect the real design
should be paid special attention in the future. During this project, all of us learned well about
challenges involved when designing high frequency converters.
Our device would have good operational capability with a working power source. Further
development of the inverter to be operational at 100 kHz or reducing the frequency to a lower value
that can be still functional to create eddy currents in the graphite crucible will make our device well
operational for the intended purpose of melting aluminum cans. Improvements can also be made for
the heating element after testing with a proper power source. Number of turns in the inductor can be
reduced if high enough temperatures can be reached with lower turns. This can reduce the cost of
the device as less litz wire would be used and litz wire is the most expensive component of our
device. Depending on test results, thickness of the insulation can also be reduced to make the
heating element more compact and also to reduce the use of insulation material.
The finished product of our device would come in a well-insulated packaging. It would be a
simple plug-in and use product with the conventional power outlets. The power supply would
include a rectifier and a inverter in a safe packaging with good cooling that can be plugged into an
ac-outlet. The heating element would come as a detachable item from the power supply and would
include simple plug-in and use with the power supply. This device could also be further developed
to be used with an aluminum can collection machine similar to what we see nowadays used in
grocery stores to crush cans and store until collected by recycling companies.
Page 21 of 22
List of Appendices
1. Solving the Maxwell Equations
2. MATLAB Code - Computing Power
3. MATLAB Code - Solving the Thermal Model
4. Project Plan
5. Business Aspects
References
Brennan, John. "Importance of Recycling Aluminum Cans." Home Guides | SF Gate,
http://homeguides.sfgate.com/importance-recycling-aluminum-cans-79304.html. Accessed 25
May 2019.
R. Phadungthin and J. Haema, "Application study on induction heating using half bridge LLC
resonant inverter," 2017 12th IEEE Conference on Industrial Electronics and Applications
(ICIEA), Siem Reap, 2017, pp. 1582-1585.
G.Liliana, “ Analysis and Design of a 500 kHz Series Resonant Inverter for Induction Heating
Applications,” Ph. D. dissertation, Virginia Polytechnic Institute and State University , Virginia,
pp.8-9,1995.
C. R. Sullivan, "Optimal choice for number of strands in a litz-wire transformer winding," in IEEE
Transactions on Power Electronics, vol. 14, no. 2, pp. 283-291, March 1999.
J.Pyrhonen, T.Jokinen and V. Hrabovcova, Design of Rotating Electrical Machines, John Wiley &
Sons,2008,pp-463-472.
Page 22 of 22
1. Solving the Maxwell Equations

"⃗

$

% $&

$'

()*+,-). /: 12 , 42
()*+,-). //: 122 , 422
5-,: 46 , 1 = 0

Maxwell equations:
I⃗ = J⃗
∇×ℎ

LMI⃗
∇ × +⃗ = −
L*

Linear, isotropic and homogeneous constitutive equation:

J⃗ = 1+⃗

MI⃗ = 4ℎ I⃗

Interface conditions:
YℎI⃗Z − ℎI⃗[ \ ∙ *⃗ = ^_

(+⃗Z − +⃗[ ) ∙ *⃗ = 0

YMI⃗Z − MI⃗[ \ ∙ bI⃗ = 0

(J⃗Z − J⃗[ ) ∙ bI⃗ = 0

LMI⃗ LℎI⃗
I⃗\ = ∇ × J⃗ = 1∇ × +⃗ = −1
∇ × Y∇ × ℎ = −14
L* L*

In cylindrical coordinates we have:

L [ ℎ[ 1 Lℎ[ Lℎ[
+ − 14 = 0
L, [ , L, L*

Using the complex transformation:

ℎ[ = g(,) cos(h*) → ℎ[ = g (,) + jkl

qr
So ℎ[ = ℛ+oℎ[ p and s = ^h g(,) + jkl
ql

The differential equation becomes:

v [ g 1 vg
+ − ^h41g = 0
v, [ , v,

Its solutions are composed of the modified Bessel function xy and zy

g(,) = 5 x& ({,) + | z& ({,)

Z}j [
with { = ~
and = ÄÅÇk

The identification of A and B comes with the boundary condition.

vg
ÖÜ (,) = − = −5{xáZ ({,) + |{záZ ({,)
v,

In , = $ , g2 ($) = g_ ;
I⃗Z ∙ *⃗ = ℎ
ℎ I⃗[ ∙ *⃗

In , = $& , g2 ($& ) = g22 ($& ) ;
I⃗Z ∙ *⃗ = ℎ
ℎ I⃗[ ∙ *⃗
Ö2 ($& ) = Ö22 ($& ) ;
+⃗Z ∙ *⃗ = +⃗[ ∙ *⃗

In , = $' , Ö22 ($' ) = 0 ;
+⃗Z ∙ *⃗ = +⃗[ ∙ *⃗
In the air +⃗[ = 0

It gives the following set of equations, which can be solved with symbolic computation.

52 x& ({2 $) + |2 z& ({2 $) = g_

52 x& ({2 $& ) + |2 z& ({2 $& ) = 522 x& ({22 $& ) + |22 z& ({22 $& )

{ {
[−52 xáZ ({2 $& ) + |2 záZ ({2 $& )] 2 = [−522 xáZ ({22 $& ) + |22 záZ ({22 $& )] 22
12 122

−522 {22 xáZ ({22 $' ) + |22 {22 záZ ({22 $' ) = 0
2. MATLAB Code - Computing Power
clear; close all; format long g; clc;
% Material properties
mu0 = 4*pi*1e-7;
mur_I = 1;
mu_I = mur_I*mu0;
mur_II = 1;
mu_II = mur_II*mu0;
sigma_I = 170e3;
sigma_II = 37.7e6;
% Dimensions
R=35.3e-3;
Ro=23e-3;
Ri=Ro-100e-6;
L=113e-3;
L=1/4*L
kL=1.1;
D_litz = 0.5106e-3;
k_litz = 1; % in order to including small spacing between the wires
N_layer =1;
% Source
fs = 100e3;
Is = 2.1;
Ns=round(N_layer*L/(k_litz*D_litz)); % Number of turns
Hs = Ns*Is/(kL*L+D_litz);
fprintf('Calculation of the power transmitted by eddy current in an

aluminum tube\n\n');
fprintf('Outer Tube dimensions:\n\t Outer radius R = %.3g mm\n\t Inner

radius Ro = %.3g mm\n\t Length L = %.3g mm\n\n', R*1e3,Ro*1e3,L*1e3);
fprintf('Inner Tube dimensions:\n\t Outer radius Ro = %.3g mm\n\t Inner

radius Ri = %.3g mm\n\t Length L = %.3g mm\n\n', Ro*1e3,Ri*1e3,L*1e3);
fprintf('Magnetic field source:\n\t Amplitude Hs = %.3g kA/m at r=Ro\n\t

Current Amplitude Is = %.3g A for %d turns with %d layers\n\t Frequency
fs = %.0f kHz\n\n', Hs/1e3,Is,Ns,N_layer,fs/1e3);
% discretization of the raidus

Nr = 1500;
rI = linspace(Ro,R,Nr);
rII = linspace(Ri,Ro,Nr);
% Skin depth
delta_I = sqrt(2/(2*pi*fs*mu_I*sigma_I));
delta_II = sqrt(2/(2*pi*fs*mu_II*sigma_II));
fprintf('Eddy current characteristic\n\t Skin depth in outer tube: %.3g

mm\n', delta_I*1e3);
fprintf('\t Skin depth in inner tube: %.3g mm\n\n', delta_II*1e3);

a11 = besseli(0,(1+1j)/delta_I*R);
a12 = besselk(0,(1+1j)/delta_I*R);
a21 = besseli(0,(1+1j)/delta_I*Ro);
a22 = besselk(0,(1+1j)/delta_I*Ro);
a23 = -besseli(0,(1+1j)/delta_II*Ro);
a24 = -besselk(0,(1+1j)/delta_II*Ro);
a31 = -(1+1j)/delta_I/sigma_I*besseli(-1,(1+1j)/delta_I*Ro);
a32 = (1+1j)/delta_I/sigma_I*besselk(-1,(1+1j)/delta_I*Ro);
a33 = (1+1j)/delta_II/sigma_II*besseli(-1,(1+1j)/delta_II*Ro);
a34 = -(1+1j)/delta_II/sigma_II*besselk(-1,(1+1j)/delta_II*Ro);
a43 = -(1+1j)/delta_II/sigma_II*besseli(-1,(1+1j)/delta_II*Ri);
a44 = (1+1j)/delta_II/sigma_II*besselk(-1,(1+1j)/delta_II*Ri);
A_I = -(Hs*(a22*(a33*a44-a34*a43)-
a23*a32*a44+a24*a32*a43))/(a12*(a21*(a33*a44-a34*a43)-
a23*a31*a44+a24*a31*a43)+a11*(a22*(a34*a43-a33*a44)+a23*a32*a44-
a24*a32*a43));
B_I = (Hs*(a21*(a33*a44-a34*a43)-
a23*a31*a44+a24*a31*a43))/(a12*(a21*(a33*a44-a34*a43)-
a24*a32*a43));
A_II = (Hs*(a22*a31*a44-a21*a32*a44))/(a12*(a21*(a33*a44-a34*a43)-
a24*a32*a43));
B_II = -(Hs*(a22*a31*a43-a21*a32*a43))/(a12*(a21*(a33*a44-a34*a43)-
a24*a32*a43));
hz_I = A_I * besseli(0,(1+1j)/delta_I*rI) + B_I *

besselk(0,(1+1j)/delta_I*rI);
jphi_I = -(1+1j)/delta_I * A_I *besseli(-1,(1+1j)/delta_I*rI) +

(1+1j)/delta_I * B_I *besselk(-1,(1+1j)/delta_I*rI);
hz_II = A_II * besseli(0,(1+1j)/delta_II*rII) + B_II *

besselk(0,(1+1j)/delta_II*rII);
jphi_II = -(1+1j)/delta_II * A_II *besseli(-1,(1+1j)/delta_II*rII) +

(1+1j)/delta_II * B_II *besselk(-1,(1+1j)/delta_II*rII);
p_I = (jphi_I.*conj(jphi_I))/(2*sigma_I);
p_II = (jphi_II.*conj(jphi_II))/(2*sigma_II);
P_I = 2*pi*L*trapz(rI,rI.*p_I);
P_II = 2*pi*L*trapz(rII,rII.*p_II);
% Calculation of the inductance

Flux = 2*pi*(Ri^2/2*mu0*real(hz_II(1))+ mu_I*trapz(rI,rI.*real(hz_I))+
mu_II*trapz(rII,rII.*real(hz_II)));
Ls = Ns * Flux/(Is);
Vs = 2*pi*fs*Ls*Is;
Papp=Vs*Is;
fprintf('\t Inductor characteristics:\n');

fprintf('\t Inductance : L = %.3g \x03BC H \n',real(Ls)*1e6);
fprintf('\t Voltage required (resistance neglected): V = %.3f V \n',Vs);
fprintf('\t Transmitted power in outer tube: P_I = %.3f W \n',P_I);
fprintf('\t Transmitted power in inner tube: P_II = %.3f W \n',P_II);
fprintf('\t Total Transmitted power: P = %.3f W \n',P_I+P_II);
fprintf('\t Apparent power : S = %.3f kVA \n\n',Papp/1e3);
% Display the distrubution of the electro-magnetic quantities

r=[rII rI];
hz=[hz_II hz_I];
jphi=[jphi_II jphi_I];
p=[p_II p_I];
P=P_I+P_II;
figh=figure(1);
subplot(3,1,1);
plot(rII*1e3,real(hz_II)/1e3,'b',rII*1e3,imag(hz_II)/1e3,'r',rI*1e3,real(h
z_I)/1e3,'c',rI*1e3,imag(hz_I)/1e3,'m');
xlabel('r [mm]');
ylabel('field [kA/m]');
legend('Real in inner tube','Imaginary in inner tube','Real in outer
tube','Imaginary in outer tube','Location','Best');
subplot(3,1,2);
plot(rII*1e3,real(jphi_II)*1e-6,'b',rII*1e3,imag(jphi_II)*1e-
6,'r',rI*1e3,real(jphi_I)*1e-6,'c',rI*1e3,imag(jphi_I)*1e-6,'m');
xlabel('r [mm]');
ylabel('current density [A/mm^2]');
subplot(3,1,3);
plot(rII*1e3,real(p_II)/1e6,'b',rII*1e3,imag(p_II)/1e6,'r',rI*1e3,real(p_I
)/1e6,'c',rI*1e3,imag(p_I)/1e6,'m');
xlabel('r [mm]');
ylabel('power density [MW/m^3]');
hcv = 10;
S=2*pi*R*L+2*pi*R^2;
q=P/S;
dT= q/hcv;
fprintf('Thermal characteristic\n\t Temperature rise : \x0394 T = %.0f

\x00B0 C \n',dT);
fprintf('\t Fusing temperature of the aluminium : T = 660 \x00B0 C\n');
fprintf('\t Fusing temperature of the steel : T = 1 450 \x00B0 C\n');
fprintf('\t Fusing temperature of the graphite for crucible : T = 3 850

\x00B0 C\n\n');
L=113e-3;
Thermal_model_IH
3. MATLAB Code - Solving the Thermal
Model
%% Thermal Resistances
l_y=19*1.1e-3; %Number of insulation layers
A_L=134e-3; %Aluminum Can length
L_th=D_litz/2; %Litz wire radius
alpha_C=30; %Convection Coefficient

lam_cop=380; %Conductivity of Litz wire
lam_al=220; %conductivity of Aluminum
lam_in=0.045; %conductivity of Insulation
lam_gh=168; %conductivity of graphite
Ral_out=26.65e-3; % Outer radius of Aluminum

Ral_in=26.59e-3; % inner radius of Aluminum
Ral=(log(Ral_out/Ral_in))/(2*pi*lam_al*A_L); %Thermal resistance of

Aluminum
Rin=(log((l_y+R)/R))/(2*pi*L*lam_in); %Thermal resistance of Insulation
Rg=(log(R/Ro))/(2*pi*L*lam_gh); %Thermal resistance of Graphite
RL=(log((R+l_y+2*L_th)/(R+l_y)))/(2*pi*L*lam_cop); %Thermal resistance of
Litz wire
RC1=(1/(alpha_C*2*pi*(R+l_y+2*L_th)*L)); % Convection Resistance Litz wire
side
n=70; %Number of Strands

l_wire = 2*pi*(R+l_y+D_litz/2)*Ns+50e-3; %length of total turns and
additional length
L_rho=1.72e-8;
d_43=0.05641e-3;
S_litz = n*pi*(d_43/2)^2;
R_litz = 2.8
%% Graphite Resistance
Rg_rho=7.837e-6;
Rg_r=(Rg_rho*L)/(pi*((R)^2-(Ro)^2));
%%Aluminum Resistance
Ral_rho=2.65e-8;
Ral_R=(Ral_rho*L)/(pi*((Ral_out)^2-(Ral_in)^2));
%%Losses
P_L=Is^2*R_litz; %Litz wire loss
V_need = sqrt((R_litz*Is)^2+Vs^2)
P_G=P_I; %Graphite loss
P_A=P_II; %Aluminum loss
%% Thermal Resistances Aluminum Side

lamb_air=66.32e-3;
R_air=((A_L/3))/(lamb_air*pi*(Ral_out)^2); % Air resistance
e_al=0.24e-3;
R_altop=(e_al)/(lam_al*pi*(Ral_out)^2); % Aluminum Top side resistance
R_cv2=(1/(alpha_C*pi*(Ral_out)^2)); %Convection Resistance Aluminum Side
r_2=26.53e-3; %excluding Aluminum thickness
r_1=0.1e-3;
R_almid=(log(r_2/r_1)/(2*pi*A_L*lamb_air));
%%Equivalent Resistances
R1=(RC1+(RL/2));
R2=((RL/2)+(Rg/2)+Rin);
R3=((Rg/2)+(Ral/2));
R4=((Ral/2)+R_air+R_altop+R_cv2+R_almid);
%% Equations
Tamb=20; %ambient temperature
F = ((R2*R3)*(R3+R4))/((R3*(R3+R4))+(R2*(R3+R4))-(R2*R4));
Q = F*(((R4/(R3+R4))*((((Tamb/R4)+P_A))+P_G)));
E = (R1*(R2)^2)/((R2^2)-(F*R1)+(R1*R2));
T_A = E*((Tamb/R1)+P_L+(Q/R2));
T_B = F*(((T_A/R2)+(R4/(R3+R4)))*(((Tamb/R4)+P_A)+P_G));
T_C = R3*R4/(R3+R4)*(Tamb/R4+T_B/R3+P_A);
disp(T_A)
disp(T_B)
disp(T_C)
TA = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_G*R1*R3 +

P_G*R1*R4 + P_L*R1*R2 + P_L*R1*R3 + P_L*R1*R4)/(R1 + R2 + R3 + R4)
TB = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_A*R2*R4 +

P_G*R1*R3 + P_G*R1*R4 + P_G*R2*R3 + P_G*R2*R4 + P_L*R1*R3 + P_L*R1*R4)/(R1
+ R2 + R3 + R4)
TC = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_A*R2*R4 +

P_A*R3*R4 + P_G*R1*R4 + P_G*R2*R4 + P_L*R1*R4)/(R1 + R2 + R3 + R4)
Aalto University
Year 2019
Project plan
Project #26
Date: 1.2.2019
Yuvin Kokuhennadige
Md Masum Billah
Jaakko Lind
Page 1 of 21
Information page
Students
Yuvin Kokuhennadige
Md Masum Billah
Jaakko Lind
Project manager
Yuvin Kokuhennadige
Official Instructor
Dr. Floran Martin
Starting date
10.1.2019
Approval
The Instructor has accepted the final version of this document
Date: 1.2.2019
Page 2 of 21
1) Background
This project is based on electromagnetic induction, as time-dependent magnetic field
induces electric current to a conductive material. Induced currents are referred to as eddy currents,
and current generates heat as it flows through a conductive material, such as metal. This is the
general working principle behind all induction heating devices, most common of which may be the
induction stove. In industrial applications, induction heaters can be used to generate heat in metallic
objects locally and efficiently, even to the point where metals are melted completely.
The project work consists of designing and building an industrial induction heater, capable
of melting aluminum cans. Changing magnetic field is generated with an inductor, and the
workpiece (in this case the aluminum can) is placed inside it to produce eddy currents and therefore
heat within the workpiece. An inductor requires alternating current input, which can be supplied
using high power transistors, such as MOSFETs or IGBTs. These transistors can be controlled by a
function generator or dedicated gate-drivers to achieve desired output frequency, voltage and
current required for the magnetic field and therefore eddy currents. Also, some additional cooling
has to be introduced to the inductor coil to prevent it from overheating, as only the workpiece
should be heated.
Motivations for this device include more efficient recycling (and shipping) of aluminium
cans and potentially even larger pieces of aluminium, such as induction machine rotors. If cans
would be melted after collecting, they would not take up so much space and more material could be
shipped at once, with just a relatively slight change to the recycling procedure. Also, this device
would enable on-site melting of material, making the whole recycling process more efficient.
Recycling of aluminium is much less expensive and energy-intensive, and more sustainable than
creating new aluminium, as it requires approximately 95% less energy compared to generating new
aluminium from minerals.
2) Expected Output
As covered in section 1, the goal of this project is to melt aluminium cans using an induction
heater. The goal and expected output of the device is to be able to create desired frequency, current
and voltage to the induction coil which induces needed eddy currents on the workpiece, in order to
melt it. The system inputs are aluminium cans and power to the power electronics so that the output
is melted aluminium which can be processed again. The system must be robust enough to withstand
the high temperature and high currents needed for the melting process. One of the goals for this
project is good performance for the system. The melting process should not take extended period of
time. The user would like the aluminium to melt as fast as possible. The time is the key issue of the
system. The system also needs to be safe for the user and not cause any hazards to the surroundings.
Proper insulation and cooling system will be there to prevent any unwanted events.
The expected user of the system is one person who should be able to use the heater very
easily. Only one switch is needed for this system to work and perform the melting process. The
system could later be used as an example to create larger scale recycling systems for aluminium
cans as our project is not designed to process large number of cans in short period of time.
When the project is ready and we confirm that it works as intended, we can decide how to
present it. There are two options for this demonstration: either we can show the melting process in
action or shoot a video of it in safer environment and then present the outcome on screen for the
viewers. The way of demonstration can be specified after we know exactly how the finished system
works. Showing a video is safer option however it’s not as exciting as real physical demonstration.
Page 3 of 21
3) Phases of the Project
This project is split into phases in order to work with a higher-level goal in mind.
M1 Planning (Deadline: 4.2.2019)
In the planning phase, we layout a plan to complete the project successfully and in a timely
manner. In this phase, we can clearly identify the objective of the project, required project
outcomes, scheduling, budgeting, division of labour and so on. Some literature review will
also be done in order to familiarize ourselves with the project. This document (Project Plan) is
the documented version of the plan for this project.
M2 Conceptualization (Deadline: 18.2.2019)

The phase where intense literature review is done to understand each part of the project. The
concepts necessary to implement the project will be identified in this stage.
M3 Prototyping (Deadline: 18.3.2019)

Identified concepts will be tested in this phase by implementing a preliminary model. This
prototype will be the base for this project. After preliminary testing, improvements would be
done for this prototype directly if possible.
M4 Subsystem completion (Deadline: 15.4.2019)

In this phase, the prototyped model is taken into consideration as subsystems. Each subsystem
will be tested to evaluate its performance. Each subsystem will then be improved to be more
efficient and reliable if possible.
M5 System completion and integration (Deadline: 6.5.2019)

Separately tested and improved subsystems will be integrated in this phase to complete the
system. Integration testing will be conducted to make sure the subsystems can operate as
anticipated.
M6 Final delivery (Deadline: 20.5.2019)

In order to prepare for delivery, the project will be tested for the intended application. The
final product will be demonstrated to the instructor, advisors and to others who are interested.
M7 Presentation (Deadline: 21.5.2019)

A poster presentation will be prepared to present the project at the Final Gala. Developed
project could also be on display. Attendees will be able to get a detailed background of our
project and we will be available to answer any questions they may have. The poster designs
should be ready by May 13th for submission.
M8 Project Report (Deadline: 31.5.2019)

The project report will present details of how the project was developed, the problems faced
during development and any significant improvements that could be made to the product to be
more useful. The report will also include measurements during testing, details of set up used
and details of materials and parts used.
Page 4 of 21
4) Work breakdown structure (WBS)
Induction Heating Device ( 810 h, 100%)
1. Concept (139 h, 17%)

1.1 Project plan (48 h)
1.2 Literature review (55 h)
1.3 Identify needs (36 h)
2. Development (142 h, 18%)

2.1 Converter design (48 h)
2.2 Transformer design (18 h)
2.3 Induction coil design (24 h)
2.4 Thermal model analysis (24 h)
2.5 Materials list (20 h)
2.6 Pre cost analysis (8 h)
3. Implementation (206 h, 25%)

3.1 Materials gathering (14 h)
3.2 Converter ( 96 h)
3.3 Transformer (24 h)
3.4 Induction coil (16 h)
3.5 Cooling System (36 h)
3.6 Connections setup (20 h)
4. Finalization (66 h, 8%)

4.1 Performance analysis (4 h)
4.2 Troubleshooting (48 h)
4.3 Risk analysis (6 h)
4.4 Final inspection (4 h)
4.5 Post cost analysis (4 h)
5. Documentation ( 192 h, 24%)

5.1 Business Aspects Presentation (48 h)
5.2 Business Aspects Documents (48 h)
5.3 Final Report (96 h)
6. Communication (65 h, 8%)

6.1 Meeting Time (25 h)
6.2 Gala Day (40 h)
Page 5 of 21
5) Work packages and Tasks of the project and Schedule
5.1) Work packages
5.2) Tasks
WP-1 Project Management and Coordination
1.1 Scheduling (25 h)
1.2 Budgeting (12 h)
1.3 Defining division of labour ( 14 h)
1.4 Project planning (48 h)
1.5 Risk evaluation (6 h)
1.6 Gala Day (40 h)
WP-2 Power Electronics Conceptualisation

2.2 Identify Needs (15 h)
2.3 Select Components (10 h)
2.4 Simulate inverter (28 h)
2.5 Simulate rectifier (20 h)
2.6 Simulate transformer (28 h)
2.7 Making material list and order ( 10 h)
Page 6 of 21
WP-3 Coil Design Conceptualisation
3.3 Calculate Frequency ( 3 h)
3.4 Copper tube thickness (2 h)
3.5 Copper tube diameter (2 h)
3.6 Coil diameter (2 h)
3.7 Finding Number of coil turns (4 h)
3.8 FEM(M) simulation (24 h)
3.9 Making materials list and order (5 h)
WP-4 Cooling System Conceptualisation

4.3 Selecting water pump or Fan (3 h)
4.4 Making materials list and order (5 h)
WP-5 Power Electronics Implementation

5.1 Design PCB layout (30 h)
5.2 Soldering parts (60 h)
5.3 Providing insulation (5 h)
5.4 Transformer coil forming (24 h)
WP-6 Coil Design Implementation

6.1 Bending copper tube to make an inductor (8 h)
6.2 Fabricating the mount with power supply (8 h)
WP-7 Cooling System Implementation

7.1 Selecting space for pump installation ( 6 h)
7.2 Installing water pump (30 h)
WP-8 Testing Power Electronics

8.1 Checking required voltage ( 1 h)
8.2 Checking required current ( 1 h)
8.3 Checking required frequency (1 h)
8.4 Calculate efficiency (3 h)
WP-9 Testing Coil

9.1 Checking voltage through current (1 h)
9.2 Checking current through coil (1 h)
9.3 Calculate resistive losses (3 h)
WP-10 Testing Cooling System

10.1 Ensure sufficient water flow (2 h)
10.2 Checking time accuracy of water flow (1 h)
Page 7 of 21
WP-11 System Integration
11.1 Connecting the whole setup (20 h)
11.2 Overall performance evaluation ( 4 h)
11.3 Contingency planning if necessary (33 h)
11.4 Final demonstration (4 h)
WP-12 Documentation
12.1 Business aspect presentation (48 h)
12.2 Business aspects documents (48 h)
12.3 Final Report (96 h)
5.3) Detailed schedule
Page 8 of 21
6) Work resources (Personal availability during the project)
Personal availability of each group member is mentioned here in order to evaluate how
much work each person can put towards the project during different times depending on their
changing schedules. By balancing out the work between one member who has a busy week with a
member who is free, the project can progress steadily.
Table 1. Number of hours available for the project (excluding lectures and seminars) per week.
Yuvin Joni-Markus
Jaakko Lind Md Masum Billah
Kokuhennadige Hietanen
Week 2 2 5 2 2
Week 3 10 15 15 15
Week 4 15 15 15 10
Week 5 15 8 10 15
Week 6 8 15 12 8
Week 7 15 10 12 6
Week 8 15 10 12 15
Week 9 4 12 14 6
Week 10 8 12 8 7
Week 11 8 12 6 9
Week 12 8 12 12 15
Week 13 8 12 12 8
Week 14 4 5 4 12
Week 15 4 5 4 5
Week 16 12 12 14 10
Week 17 12 10 12 12
Week 18 12 10 10 6
Week 19 12 5 8 10
Week 20 15 5 7 15
Week 21 4 5 6 7
Week 22 10 5 6 15
Total 201 200 201 208
Page 9 of 21
7) Cost plan and materials
Maximum budget defined by the instructor in the preliminary meeting was 500 Euros.
Budget is controlled by the project manager, and all purchases have to be approved by him before
ordering is completed. As the responsibility of budget management is focused to a single person,
chances of obscurity are greatly decreased.
Table 2. Cost Estimation

Item Type Quantity Price per piece Estimated cost
(€) (€)
Rectifier set Device 1 100 100
MOSFETs or IGBTs Component 12 2.05 24.60
Fusing Component 4 6 24
Free-wheeling diodes Component 12 5 60
Driver IC Component 12 3 36
Zener diodes Component 12 0.5 6
Optocouplers Component 12 0.5 6
Inductor Component 2 10 20
Inductor mounting Service 1 50 50
Fan Component 2 7 14
Pump Device 1 10 10
Tubing Component 2 5 10
Additional General - - 100
Total cost 360.6
Page 10 of 21
8) Other resources
Besides all the components we need some other resources for this project as well. The most
notable resource is the working place we are supposed to use for the construction of the system. The
working place is going to be the laboratory of the Department of Electrical Engineering. We will
need keys for the facility, and this can be discussed with our instructor. In the laboratory we will be
using one table for our project and keep our place organized so that it doesn’t affect work of other
people.
There is most likely going to be a need for some tool to shape the copper induction coil. For
this we are going to need some tools that the university has. We will need at least some instruction
and supervision for using such a tool. We will communicate about this with our instructor as he is
the one knowing who we should be working with in this case. The needed welding tools are more
easily accessible and can use them with less or completely without supervision.
Other than these resources we are of course going to use the electricity that is provided in
the laboratory and use all the required safety measures that are introduced to us. In our project we
won’t be needing computers from the university as we can use our own laptops.
9) Project management and responsibilities

Important project roles and responsibilities of each role is defined below.
Role Responsibilities
Project Manager ● Planning work

(Yuvin Kokuhennadige) ● Providing access to resources
● Reporting progress
● Budget management
● Making sure overall work progresses and deadlines are met
● Leading overall technical aspects of the project and delegating
● Preparing meeting agendas and reserving meeting rooms
● Placing orders for materials/parts to complete overall project
Instructor ● Provide rough background about the project

(Dr. Floran Martin) ● Observe progress of the project
● Provide expert technical advice if needed
● Ensure safety during experimental testing
● Review and approve documentation before submission
Coil Design Lead ● Lead developing Electromechanics subsystem

(Md Masum Billah) ● Responsible for system integration
● Making sure design deadlines are met per schedule
● Placing orders for materials/parts specific to coil design
Power Electronics Lead ● Lead developing Power Electronics subsystem

(Joni-Markus Hietanen) ● Making sure design deadlines are met per schedule
● Placing orders for materials/parts specific to power electronics
Cooling System Lead ● Lead developing the cooling system

(Jaakko Lind) ● Making sure design deadlines are met per schedule
● Placing orders for materials/parts specific to the cooling system
Page 11 of 21
10) Project Meetings
Project meetings between group members and the instructor will take place once a week
unless otherwise suggested that more meetings are needed depending on weekly needs of the
project. In the early stages of the project, meetings will be for understanding the topic in detail and
to create the project plan. After creating the project plan, implementation will begin and the project
meetings will be held to track progress of the project and to discuss any issues that the project faces.
Preparing meeting agendas is the responsibility of the project manager. The agenda will be
shared with the attendees by email at least 24-hours before the meeting. Agenda will also be
available on the Google Drive folder, ELEC-E8004 Project Work -> Agendas. The template for
project meeting agendas is shown below:
Meeting Agenda
Date: dd.mm.yyyy
● Select memokeeper.
● Updates relevant to overall project since last meeting.

● Updates specific to the coil design.
● Updates specific to power electronics.
● Compare the progress with planned schedule.

< include.planned schedule >
● If falling behind the planned schedule, plans and action on how to catch up.
● What should be done before next meeting by each person.
● Decide next meeting date, time and place.
* Next meeting will commence at the exact time decided and mentioned in the meeting minutes.
(Usually at the beginning of the hour, unless otherwise specified.)
Page 12 of 21
Meeting memos will be prepared in order to refer back to decisions made at meetings,
remind assigned tasks for each person and any other important discussion that should be referred to
during the tasks for the week. Meeting memos could be taken by any member of the group other
than the project manager, as the project manager should lead the discussion of agenda items. The
template for project meeting memos is shown below:
Meeting Memo
Date: dd.mm.yyyy
Memokeeper:
For each phase of the meeting take notes of:

● Decisions made at the meeting.
● Tasks assigned to a specific person.
● Important discussions.
* Please follow this format and take notes as bullet points. When assigning tasks, include the name
of the person in bold. After the meeting, please upload the final memo to the Google Drive folder,
ELEC-E8004 Project Work -> Meeting Memos, within 24-hours.
Overall project updates

● ...
Coil design updates

● ...
Power electronics updates

● ...
Inconsistencies with planned schedule

● ...
Tasks to be completed before next meeting

● Yuvin:
● Masum:
● Joni-Markus:
● Jaakko:
Next meeting
Date: dd.mm.yyyy
Time:
Place:
* Next meeting will commence at the exact time mentioned.
Page 13 of 21
11) Communication plan
Peer Meeting Schedule
Date Agenda Time Types
17.01.2019 Preliminary Report 13.00-14.00 Face to Face
22.01.2019 Project Plan 16.00-17.00 Online
29.01.2019 Project Plan 12.00-14.00 Face to Face
02.02.2019 Project Plan 15.00-16.00 Online
04.02.2019 Design kickoff 11.00-13.00 Face to Face
11.02.2019 Preliminary Design 12.00-11.30 Face to Face
15.02.2019 Final Design 17.00-18.00 Online
25.02.2019 Implementation Kickoff 12.00-14.00 Face to Face
31.02.2019 Business Aspects Presentation 12.30-14.00 Face to Face
07.03.2019 Business Aspects Presentation 15.00-16.00 Online
08.03.2019 Business Aspects Documents 16.30-18.00 Online
13.03.2019 Business Aspects Documents 11.00-12.00 Face to Face
29.03.2019 Implementation 10.00-11.00 Online
07.04.2019 Implementation 12.30-13.30 Face to Face
12.04.2019 Implementation 11.00-130.00 Face to Face
23.04.2019 Poster Design 13.00-14.00 Face to Face
30.04.2019 Performance Evaluation 12.00-13.00 Face to Face
05.05.2019 Final Report Kickoff 14.00-16.00 Face to Face
09.05.2019 Report writing 18.00-19.00 Online
12.05.2019 Report writing 16.00-17.00 Online
17.05.2019 Gala Day 15.00-16.00 Face to Face
28.05.2019 Final Report 13.00-15.00 Face to Face
30.05.2019 Final Report 18.00-20.00 Online
Page 14 of 21
Instructor Meeting Schedule
Date Agenda Time
18.01.2019 Preliminary Report 11.30-12.30
01.02.2019 Project Plan 11.00-12.00
13.02.2019 Design Aspects 10.30-11.30
21.02.2019 Final Design Outcomes 11.30-12.30
26.02.2019 Implementation Aspects 12.00-13.00
06.03.2019 Business Aspects 11.00-12.00
12.03.2019 Business Aspects Documents 10.00-11.00
27.03.2019 Implementation Issues 12.00-13.00
30.04.2019 Performance Evaluation 12.30-13.30
15.05.2019 Final Report and Gala Day 11.00-12.00
17.05.2019 Gala Day 10.30-11.00
29.05.2019 Final Report and Giving Thanks 11.00-12.00
12) Risks
General project risk analysis has in this case been defined to consist of six steps. These six
steps are used to clarify the characteristics of individual risks, their probability and potential
damage they possess to overall project work. As we’re dealing with a hardware-based project,
safety factors are being considered within these risks, to ensure a safe working environment during
the whole project. Steps are presented below:
Project Risk Analysis:

1. Risk event: What might happen to affect your project or individuals?
2. Risk timeframe: At what phase of the project is it likely to happen?
3. Probability: What’s are the chances of it happening?
4. Severity of the impact: What’s the expected outcome and how does it affect the project?
5. Recognition of factors: What events might forewarn or trigger the risk event and how to
recognize them in advance?
6. Handling: Concrete measures to reduce risk.
Page 15 of 21
Table 3. Risk Analysis
Risk Type Severity Recognition
Delay 1 Careless planning and impossible deadlines
Aluminium oxide 1 Impurities on the recycled end product
Component shipping 2 Ordering components from suspicious sources
Component expenses 3 Careless planning and overpriced components
Paint fumes 3 Paint on the cans has to be noted and removed
Design flaws 4 Careless planning and insufficient simulations
Fire hazard 5 Overheating of inductor or ignition of material
Severity scale:
1 Risk is there, minor damage may occur in terms of time-management.
2 Low-level damage may occur. Fixing the damage may take time and effort.
3 Mid-level damage may occur in terms of budget, time management or minor injuries.
4 Genuine risk exists, injuries are possible.
5 Very severe safety risks. Catastrophic damage or severe bodily injury may occur.
Delay:
1. Delay is a risk that covers a lots of sectors within the project work. Overall delay may lead
to time management issues to some deadlines during the project and may in the worst case
lead to unsuccessful project altogether.
2. Delay may occur in any phase of the project.
3. Occurrence of this risk is highly probable.
4. Severity differs on magnitude and point of time in the project
5. Careless planning and impossible deadlines are factors to be considered in advance
6. Elaborate plans and early enough orders of parts may help, but delay can’t be completely
averted.
Aluminium Oxide:
1. Aluminium oxide is generated within the melting process of aluminium. It is a chemical
compound, that consists of aluminium and oxygen. It is not toxic, but creates some impurity
to the aluminium collected after melting.
2. Risk is topical after device is successfully built and pure aluminium is wished to be
recycled.
3. Occurrence of this risk is somewhat potential.
4. Severity of this risk is quite low, as it has an effect on the recycled end product rather than
being relevant on the production process of the device.
5. Impurity can be recognized from the recycled end product.
6. Impurities could be separated after melting process.
Page 16 of 21
Component Shipping:
1. Component shipping may generate significant delay to the process.
2. Risk is topical during ordering of parts.
3. Occurrence of this risk is quite probable.
4. Severity of this risk is quite low, as it only has an effect on the time management section of
the process.
5. Ordering components from suspicious sources.
6. Risks can be reduced by ordering most components simultaneously from well-established
websites and other verified sources, with previously defined shipping times.
Component Expenses:
1. Component expenses may exceed the project budget, if not carefully selected and handled
during the prototyping phase.
2. Risk is topical during the whole project, but especially at the prototyping phase.
3. Occurrence of this risk is possible.
4. Severity of this risk is mid-level, as exceeded budget is one measure of successful project.
5. Careless planning and overpriced components or materials are the most relevant factors.
6. Careful simulations before implementation of components and price comparison before
purchasing components.
Paint fumes:
1. Harmful and irritating paint fumes may possess a health risk when inhaled. During this
project, the paint considered is located on the surface of the aluminium cans.
2. Risk is topical when heating the cans.
3. Occurrence of this inhalation risk is somewhat possible.
4. Severity is mid-level, as it may lead to some health issues during the project work.
5. Paint on the cans has to be noted beforehand.
6. Risk can be removed by removing the paint from the workpieces before applying heat to the
aluminium.
Design Flaws:
1. Design flaws is one of the biggest and widespread risks on the project, as it may lead to
serious hardware malfunctions.
2. Risk is topical around the project design phase and on the prototyping phase.
3. Occurrence of this risk is possible.
4. Severity depends on the type of design flaw and potential malfunction, but it may lead to
financial issues, time-management failures and even injuries.
5. Recognition of design flaws can be done by careful planning and simulation of different
sections of the project.
6. Sufficient simulation before implementing the physical project.
Page 17 of 21
Fire Hazard:
1. Fire hazard possesses most dangerous risk of the list, as it may lead to serious injury or
complete physical destruction of the project. Even surroundings may be in serious danger.
2. Risk is topical on prototyping phase as well as after the project has been completed.
3. Occurence of this risk is possible.
4. Severity of this risk is obvious, as a fire may lead to serious damage to the project, people
and test environment.
5. Unwanted ignition of any material or overheating of the inductor.
6. Preparation with fire extinguishing equipment as well as preliminary heat analysis and
efficient cooling system. Heating event must be constantly examined and evaluated.
13) Quality plan

The quality of every phase of the project will be monitored with the best of groups abilities.
Group members will complete their tasks trying to achieve the best possible quality as this helps the
project greatly. The whole group is responsible for quality and everyone may point out flaws or
weaknesses in any phase of the project as this makes it faster to improve the needed aspects of the
current project phase.
Before each phase of the project the group should have meetings on how to proceed and
make the next goals as clear as possible. When everyone in the group knows exactly what they are
aiming for, the quality of the project will improve. After each task the project manager will be
doing some final checking and then approve the work or point out some recommendations how to
better something. For example, when thinking about the planning phase of the project, the project
manager will read the whole document and send it to approval for the instructor if the aimed quality
is achieved.
The project manager is not fully responsible for the quality of the project, but he will be the
one approving the work of the group. This approval can be done by organizing a group meeting and
then approving the quality collaboratively. The quality approval is done differently for different
phases of the project, but the idea is the same. For example, the project plan is checked for all the
needed and accurate content that are ensure good quality. And if we think about the prototyping, the
quality can be seen by doing all the necessary testing for the system. If these tests are passed, the
wanted quality is achieved and we may proceed to next phase.
The instructor will have role in the quality of the project. He is going to be the person who
can say the final word on each project phases and give the project group feedback on the quality.
The instructor will be the final person who approves the project plan and other phases of the project.
Instructor may give the project group feedback on the quality and give suggestions to improve it if
needed.
If anyone in the group notices something that is affecting the quality in a negative way, the
person may contact other people in group chat and point out the things that were found. In case the
issue is small and can be corrected easily, the right group member will deal with the issue right
away. However, if the flaw in the quality is bigger, a group meeting should be invited, and the topic
discussed so that the project work can be continued with the improved quality.
Page 18 of 21
14) Changing this plan
Anyone in the project group is able to make initiative to ask possible changes to this project
plan. No matter how big of a change is going to be, the person should inform the group that
something worth changing is found in the document. This is easiest to do by contacting other
members in group chat. Changing something without consent of other members should not be done
unless the change is something really minor, like a spelling error.
After the initiative is taken, the group should agree on how to change the document. This is
easiest to do in a group meeting as everyone can give their opinions easily and discussion can be
made. If the change is going to be easy and straightforward, the group can agree the changes in
group chat and let the person do the needed changes. If something more significant part is going to
be changed, the group should plan it together and come to an agreement.
Changing the schedule is going to be done in the same way as any other larger scale change.
The whole project group should agree fully on changing the schedule as it affects everyone’s work.
If the proposed schedule change is fine for all the members, the change will be done to the
document. If someone is absent, the others will tell the person by message what changes are to be
made. If for example the schedule doesn’t work for the absent person, the change will be discussed
further.
If changes are made to the project plan, the changes should be also documented in the plan.
When the document is kept up to date it is easy to follow it and it prevents also misunderstandings.
The best way to keep track on the possible changes is to add one more section to the end of the
project plan. This last section could be titled for example Revision history. There we could make a
table that shows the date of the change, the person who changed it and the actual information that
changed. For example, the table could look like this:
Date Person who did the Change

change
xx.xx.xxx Xxxxxxx Something was changed in section X
Page 19 of 21
15) Measures for successful project
The definition for successful project is to build a functioning prototype capable of melting
aluminium cans in a short period of time, while reaching budget goals and technical milestones
within the defined deadlines.
Evaluation of final outcome includes functionality of the device and its parts. If all parts are
functional, induction heater is evaluated as whole, by the delay it takes to fully melt an aluminium
can. Demonstration of functional project can be done either physically on class seminar, which
possesses some obvious risks, or on laboratory conditions evaluated by the instructor. Functionality
of the finished product could be verified on safe laboratory conditions and a film demonstrating the
functionality could be viewed on seminar conditions. This gives the viewers an opportunity to
evaluate the functions without sacrificing classroom safety.
Evaluation of process is based on reaching the previously defined milestones, that describe
deadlines and targets for each section. Reaching previously defined milestones must be documented
and evaluated along the whole project process in order for the evaluation to be reliable and relevant
in the end.
Individual goals can also be defined for each student independently, as tasks within the
project work lead to different kind of learning experiences. Also it is notable, that learning goals
differ according to preliminary knowledge possessed by each individual. If all sections of the
process and areas of responsibilities are clearly divided beforehand, individual evaluation is easier.
Received feedback and self-evaluation along the project work as well as after it support the learning
goals, that students have defined.
Overall, the evaluation for a successful project consists of the previously mentioned factors,
which include a functioning prototype, reached budget limitations, reached technical milestones and
deadlines, successful demonstration of prototype functionality and its waypoints as well as
independently reached learning goals for each student.
Page 20 of 21
Appendix
1) Work Breakdown Structure (WBS)
Page 21 of 21
Aalto University
Year 2019
Business aspects
Project #26
Date: 15.3.2019
Kokuhennadige Yuvin
Billah Md Masum
Hietanen Joni-Markus
Lind Jaakko
Page 1 of 11
Information page
Students
A Kokuhennadige Yuvin
B Billah Md Masum
C Hietanen Joni-Markus
D Lind Jaakko
Project manager
Kokuhennadige Yuvin
Official instructor
Dr. Martin Floran
Starting date
19.2.2019
Approval
The instructor has accepted the final version of this document
Date: 15.3.2019
Page 2 of 11
Summary
With an enormous number of population growth and high living standard, the recycling
products are increasing day by day. Nowadays, recycling is an important issue to keep the
environment clean, save landfills and reduce the need for raw materials. Aside from these benefits,
the recycling industry can be a good source of business. Aluminum is one of the most recycled
products in the metal recycling family. Almost 40% of the recycling metals are aluminum and each
year the world is spending billion euros for recycling the Aluminium.
Aluminum beverage Can is the most recycled consumer products and takes lots of space.
Collecting Aluminum Can from consumer to the recycle industry cause a large amount of
transportation cost and huge space at the collection point. These issues can be solved by setting a
melting device in the Can collection point but the traditional melting devices are large in size and
takes lots of time to melt the Aluminium Can which is difficult to fit in the collection point. A fast
melting and equal size of Can collection machine can resolve this problem. The recycler can save
transportation cost by directly transport the molten Aluminum from collection point to the
Aluminium products manufacturers rather than taking it to the recycling center.
Induction heating system can be a game changer in Aluminium Can recycling industry
because of its fast, safe and highly efficient heating system. Therefore, our primary business goal is
to manufacture a fast, small size, efficient and eco-friendly induction melting device that can
significantly reduce the volume of the Aluminium Can by melting this in collection point and
minimize the transportation cost for the recyclers. In addition, this device can also substitute the
usage of Can collection machines.
The global market size of Aluminium recycling machinery is around 1.2 billion euros. Our
initial target is 35 companies and their 5000 collection points which will make the revenues of 50
million euros in five years. The market is quite open, homogeneous and exists almost perfect
competition. Therefore, our product can able to substitute other products easily as there are no
significant entry barriers into the market. After achieving our primary target we will expand our
market to other Aluminum recycling companies. As the recycling machinery has a longer lifetime
and the market saturation can occur in the future. Therefore, market expansion is necessary to
lessen this crisis. Our product has the ability to melt any materials who has equal or below the
melting point of Aluminum. To overcome from this market saturation we will launch our product to
the other recycling materials industry in the future.
1) Business idea
Our end product is an induction heater which includes the heating element and the power
supply. Our induction heater will be a compact heater that can reach high temperatures very fast to
melt aluminum cans. Since the main application of our design is to melt aluminum cans, the direct
customers of this induction heater would be the operator in the recycling process. This is the
company that pays for the transporting company for delivering aluminum cans from the collection
points to the melting plant. The operator also have to store the cans before they are melted, then
melt them and distribute to material utilizers. There could be indirect customers for our product who
could use this induction heater to melt or heat another type of material for many possible
applications.
Page 3 of 11
The main benefit of melting aluminum cans using a compact heater like our product is that
the melting can be done at collection points rather than at a single operational plant. Our induction
heater significantly reduces the volume of empty cans, which reduces the cost of transportation and
space required for storage before melting. Less volume means not as many trips are needed to
transport the cans from the collection points to the melting venue. This can save money that the
operator has to pay to the aluminum cans transporting companies. While that is the benefit during
transport, the operator also can benefit by having solid blocks of aluminum delivered to their
distribution venue rather than having large volumes of aluminum cans delivered. This saves space
in their facilities where otherwise all the empty cans would have had to be stored before being
melted. Meaning, the operator can save money on land space or rent cost that goes for the venue.
Our product is compact and safe to operate. Therefore, it can be operated at collection points
without much space, and safely to the operator and surrounding. This would be a competitive
advantage compared to the products currently available in the market for melting aluminum,
because they are big and have to be operated in highly controlled environments for safety reasons.
We expect to gain revenue by introducing and selling our product to operators of the aluminum
recycling process around the world. There is also the possibility that the market for our product can
be expanded to melting and heating other materials for additional revenue.
2) Product
The business idea was covered in the previous topic but here the product is covered in more
detail. The technical aspects of the product are covered as well as everything that is provided by our
company that is related to this product. The purpose of use and the benefits for the customer are
already covered in the previous section but here the service for our product is presented.
Our induction heater design is somewhat simple, and it is supposed to be easy to

manufacture and it also should be robust. The heater is easy to operate, and the advantage is that the
melting process is fast. The aluminium cans are put inside the heater’s graphite crucible where the
heating happens. After this, the heater is turned on and the aluminium will start to melt quickly after
the start-up. When the cans have melted in the heater, the heater can be turned on and after a while
the aluminium can be poured from the crucible in to wanted mould and the aluminium block is
ready to be transported after some cooling time. The heater is easy to use, and it is also safe as its
outside doesn’t heat to dangerous temperatures.
The induction heater consists of two parts: electromechanical part and power electronics.
The electromechanics part has three main components. The graphite crucible is going to be the
component that defines the actual size and melting volume of the heater. The crucible is the part
where the aluminium is put during the melting process. The crucible is enclosed with insulation that
is keeping the heat in the crucible. The insulation thickness depends on the size of the crucible used.
On top of the insulation there is the induction coil which is made by using Litz wire or something
that resembles it with its capabilities of conducting high currents without heating too much. The
insulation between the coil and the crucible is there to insulate the about 700 degrees Celsius inside
the insulation so that the used wire can operate without overheating. There has to be also a pouring
mechanism where the crucible can be inclined so that the molten aluminium can be poured out of it.
The power electronics are there to produce needed current and frequency into the coil in order to
heat up the graphite with induction. The power electronics consist mainly of voltage rectifier and
inverter. The rectifier is used to rectify the AC voltage that can be obtained from the grid. The
inverter can then use this DC voltage in order to create the wanted waveform of AC to the coil. The
Page 4 of 11
components for power electronics are selected so that they are robust and high enough quality for
this application to work for long time.
Our company’s product is the induction heater that comes as one compact package.
However, this is not all that we provide to our customers. It is possible for our company to do the
commissioning and test run for the induction heater once it is shipped to the site. This service can
be purchased when making the order for the heater. Our company can also provide our customers a
training session on how to operate the heater. Of course, the product is equipped with suitable
warranty and our company will be responsible for the spare parts and maintenance of the heater
during that time. Also, after the warranty period, we should be able to provide our customers with
spare parts and maintenance possibilities for long period of time.
3) Market situation and competitors analysis

Our customers are aluminium recycling companies, which include over 2000 companies
worldwide. The whole market worth is estimated to be around 1.2 billion Euros globally, but it’s
notable that in some countries the aluminium beverage cans are separated from regular trash and not
recycled individually as in Finland, making it more difficult for us to sell a small-scale melting
solution, compared to larger separation and melting processes. Native market in Finland consists of
only a few recycling companies, so it would make sense to target global market or at least the
market within the EU. In addition, it’s possible to expand to alternative markets with our product as
well, such as other material melting industries.
With these specifications, in Europe and the UK there are over 500 companies. Therefore, it
would be justified to evaluate, that we would be able to get around 35 customers with 5000 can
collection points. Estimated market sales would therefore be worth around 50 million Euros, which
would correspond to around 4% market share. This estimation is a bit optimistic, but the market
share would definitely be desired, considering how many of the companies are not a perfect fit to us
due to recycling infrastructure or large quantities. Also, it has to be considered, that we are able to
expand our market on demand.
The customer purchase decision process begins with a pitch or successful marketing, which
makes a potential customer aware of the product, preferably supported with exact calculations
considering percentual surplus derived from transportation and real-estate costs. After this, the
potential customer has time to carefully consider their preferred recycling system, its infrastructure
and the need for this investment. If the calculations conducted by the customer reveal a pleasant
reimbursement schedule, and the savings are considered to be sufficient, first purchase occurs in
example covering few of the busiest can collection locations. After this, the customer can choose to
invest to more products, maximizing the surplus or be satisfied with their reduced need for
transportation and real-estate. Later, reliability monitoring, service and maintenance amenities
generate revenue to us from their preliminary investment.
Our most important competitors are companies providing solutions for melting aluminium,
either with larger scale furnaces or induction heating solutions similar to ours. Indirect competitors
include companies that provide recycling solutions for other materials, recycling machine
manufacturers as well as transportation companies. Also, if we choose to proceed and evolve our
product to metal melting industry, large hydraulic press manufacturers and other melting metal
companies have to included to the competitor list.
Page 5 of 11
As competitors are divided widely between different industrial fields due to significant
indirect competition, analyzing their relation and effect to our product is not exactly
straightforward. The biggest inconvenience from our product is caused to the transportation
companies, that are not competitors in terms of providing a similar product to potential client.
However, they can adjust their pricing and therefore decrease the potential surplus the client could
achieve from our product, making them perhaps the biggest competitor out there.
Another big competitors are aluminium or other metal foundries with large furnaces. They
can provide a standardized product with high dimensions using molds to meet material utilizers
demands to manufacture new beverage cans or other aluminium commodities. This competitor is
more relevant on another part of the recycling process, but has to be considered a rival anyway.
Recycling machine manufacturers have already solved the issue we’re trying to solve by a
simple hydraulic press at the collection point. This competitor is special in a sense, that it would be
possible to be perceived as a client as well. Compared to hydraulic press technology, melting
reduces the volume of aluminium even further, providing a clean and constant piece to be packed
and shipped to recycling.
Other induction heating devices exist at a price point between 8 to 60 thousand dollars, so
our plan is to be more competitive on the pricing. Afterall, the budget for this prototype is 500-1000
Euros, so with optimized parts and production, we should be able to compete with that price.
4) Intellectual property
The intellectual property law that is most relevant to protect our product is a patent. In order
to make sure that we do not infringe the intellectual property rights of another inventor, we
conducted a freedom to operate survey. In this analysis, we searched for patent literature for issued
or pending patents relevant to our product on the European Patent Office online search. In our
search for induction heaters relevant to cans, we were able to see that there are only patents for
induction heaters that are used to heat beverages inside a beverage can in applications like vending
machines. There are no patents for induction heating devices that are used in melting aluminum
cans or melting aluminum in general using induction heating technology. However, there are
induction heaters patented for heating metals in general that could be capable to melt aluminum. It
does not specify a direct application like whether it can be used for melting aluminum cans. This
search verified that there is no product currently protected by a patent that we might infringe by
developing and selling this induction heating device commercially for melting aluminum beverage
cans for recycling purposes.
Induction heating is a very common technology used in many applications nowadays.

Induction heaters using litz wires as the source and a graphite crucible as the heating element like in
our product is not to be found in the patent databases. Therefore, there is a possibility of patenting
our design for the product. However, it is very unlikely the technology can be patented because
induction heating could be considered obvious in the electrical engineering field as a
counter-argument for the patent. Since there is no similar product to ours in the market already,
trademarking our induction heater will make sure the quality of our brand can be protected and our
product can be easily identified by customers if another competitor joins the market later with a
similar design if we cannot get patent protection.
Page 6 of 11
The technology used in our product is well known in the electrical engineering and physics
fields. Therefore, in that context we do not have anything to protect using trade secrets. Our design
can be discovered by another party as well if they are interested in developing a product for a
similar application. Therefore, patenting would protect our design better than keeping the design as
a trade secret because it would save the cost of legal proceedings that are attached with keeping the
secrecy of a trade secret as well as anyone could reverse engineer or rethink our design again and
invent their own without having our parameters or test data. In conclusion, a design patent and a
trademark for our induction heater would give the necessary protection to successfully place it in
the market.
5) Product development and technology

Current situation of the project is a relatively small prototype capable of melting whole
aluminium cans at 25 cl of volume or other small-scale scrap aluminium. Commercial products
dimensions would differ to medium- and larger-scale devices, depending on whether the
commercial product is aimed to industrial field or something more minor, like only beverage can
recycling. However, the functionality of the project will remain the same, as it would on lower level
application, so major issues or workload for larger-scale implementation shouldn’t be expected.
Commercial product also has to be tested, verified and fitted to standards, as our product may
undeniably be dangerous if it’s misused or it malfunctions.
Our rivals include the whole aluminium recycling industry, capable of large scale
aluminium melting on large furnaces and melting the product to previously determined size and
form, which is standardized by the material utilizers. There’s also indirect competition between
companies providing recycling options for other materials, recycling machine manufacturers as well
as transportation companies. In order of obtaining competitive advantage over our competitors,
constant product development is required. Our technology is not only restricted to aluminium, but
the device could easily be modified to melt other metals as well, with little or no modifications.
Also, in order to be as agile as possible on the market, the previously mentioned sizing options have
to be included to the catalog of products. The development requires significant expertise on power
electronics, electronics and especially electromechanics. Also on product development point of
view, a choice of temperature control could be added to the product. This enables a choice of
temperature level. If for example only some heat treatment on lower temperature (such as can paint
removal) was wished to be conducted or higher temperatures were wished to be reached, this could
be achieved with a simple selection of output temperature.
To accomplish this product, we have a lot of options available to the future. First of all, it’s
an alternative to sell the technology directly to bottle recycling device manufacturers as an
alternative to hydraulic presses. Other option is to sell it directly to scrapyards, where the materials
such as aluminium can be separated from other scrap metal and easily melted to blocks or desired
forms. The first option doesn’t necessarily provide revenue for the company, but may provide a
selling point as the surplus benefits the client.
Further investigation considering the average transportation prices as well as renting prices
of real-estate should be conducted, in order to find the average amount of savings generated by our
product. Right now, we’re working with estimated values and for efficient pitching purposes some
real-world values would be more convincing. Perhaps a case study could be conducted for some
individual customer, who agrees the study to be used as a selling point for potential new customers
later. After the specific values are certain, they possess a powerful tool in terms of marketing.
Page 7 of 11
Other task for accomplishing this product is material and component optimization. On the
prototype phase, we’re only considering the best and most suitable pieces of electronics etc, but
while productizing our project, the cost and reliability become more and more crucial for generating
revenue. A compromise for “good-enough” materials and components is a time-consuming task,
which doesn’t end with the finished product, but has to be continued indefinitely, as new
components and materials are introduced to market and old ones reach the end of their life.
Last, and the most important issue on the road of making this product reality is safety. As
aluminium melts at 660 degrees Celsius, efficient casing, insulation and safety functions are vital
while productizing the project. Even if everything is made according to safety standards, a fire
hazard during the use of this product exists, so surrounding conditions should be carefully
considered before using the device. This may also be perceived to be unattractive by the customer,
so marketing have to be done right.
6) Conformance
The machine must meet the standard health and safety requirements set by the organizations.
Therefore, the proper shape, size and high level of protection of our product is necessary to launch
into the market. The following machine safety directive and standards are applicable for our
product.
-Machinery Directive: 2006/42/EC

Applicable Standard: EN 60204-1:2018
Applicable Standard: ISO 12100-1:2011
As we are dealing with electromagnetic system with high operating frequency, therefore, the
product must meet the frequency disturbances standard. The following EMC directive and
associated standard is applicable in order to reducing disturbances and enhancing immunity.
-Electromagnetic Compatibility (EMC) Directive:2014/30/EU

Applicable standard: EN55011:2016
Under the following directive European Union (EU) set some tests and standard for
electrical equipment designed for use within certain voltage limits. The following standard is
particularly applicable for ensuring the safety during induction heating device installations.
-Low voltage Directive:2014/35/EU

Applicable standard: EN 60519-2005
To meet all the standard set by the EC directives and make project output ready for the
market the following improvements and modifications are required-
The product casing should be robust, well heat protective and does not allow heat
conduction to the surroundings. As the device will deal with high current and generate high
temperature, therefore, the high current and temperature tolerable materials and proper insulation
will be used to ensure safety. To reduce the Electromagnetic Magnetic Interference (EMI) an EMI
filter will be used. To collect the hot molten Aluminium a graphite crucible will be used. The
induced current will be limit by proper grounding. An alarming system will be used if any damages
or malfunctions occur inside the machine. An emergency automatic stop button will be used that
can stop the machine quickly and provide safety both for the machine and the operating person. A
Page 8 of 11
monitoring screen can be used to show the temperature, current, frequency or other necessary data.
A nameplate must be affixed to the device which will provide the rated voltage, current, frequency,
KVA ratings etc. Signals and labels will be used to warn the worker about the danger associated
with an induction heating device. A instructions manual will be provided with the device for proper
use and installation.
7) SWOT-analysis
In this section we present a SWOT-analysis for our induction heater product. The strengths,
weaknesses, opportunities and threats for our product are covered. The analysis can be divided into
two sections: internal factors and external factors. The internal factors are the strengths and
weaknesses of our product. These are mainly related to only our product are we are finding out what
are its greatest strengths and weaknesses that can be considered during the development process.
The opportunities and threats are the external factors that come outside of our product but must be
considered carefully as for example the competitors can be considered as threats. Here the SWOT
analysis is presented as a table where the success factors and risk factors are shown. Then a plan is
presented to avoid the risks in product development.
Strengths Weaknesses
● Fast aluminium melting ● The volume for aluminium is

● Compact size of the product not as big as in larger melting
● Energy efficient furnaces
● Competitive price ● The heater could pose a
● Easy usability minor fire hazard
Opportunities Threats
● Need for recycling is ● Companies don’t realize the

increasing benefits of our product
● The product reduces the need ● Transportation companies
for transportation compete with us with the
● The heater can be used for prices
other materials with similar ● Older technologies stay
melting points as aluminium viable for long period of time
The strengths and opportunities have been covered well already in this document and it is
safe to say that our product has lots of strengths as an individual induction heater. Also, it has good
opportunities to hit the market and to be valuable for the customers. There is certainly a place for
our product in the market when going through the SWOT analysis.
Page 9 of 11
There are also some weaknesses and threats for our company’s induction heater device. And
these should be taken into account during the product development. The main weakness is that the
device is not going to be capable of melting the amounts of aluminium as the competitors’ large
furnaces. Even though this can be count as a weakness, we have to think of it also as our strength.
This product should be marketed as a product that can be viable option for smaller scale aluminium
melting. The smaller size can also be advantageous if there is limited space available for the melting
process. The other weakness is that the product can pose a minor fire hazard. This is because the
heater is operating with high temperatures. The fire hazard can be avoided with proper use and
proper protection and maintenance of the product. The installation place should also be suitable for
the operation of the heater. All these aspects should be made clear for the customer so that the
hazard can be prevented.
The threats for our product are mainly coming from the competition of the market. The
companies might not actually realize the value of our product and want to stick to more traditional
products such as melting furnaces. We have to be aware of the issue and do the marketing
accordingly and well in order to gain the interest of our customers. The threat is also that the old
technology lasts for really long time in operation. We have to be able to market our product to
newer operators and to smaller recycling companies so that they can get the benefits of our product
as early as possible. Also, the transporting companies can pose a slight threat to us as they can
compete with our solution by lowering the prices and doing good contracts with operators. The
same solution can be applied here which is good marketing.
Supplement: Distribution of work and learning outcomes
The making of this document was distributed equally by chapters among the team members.
The chapters ‘Summary’ and ‘Conformance’ were completed by Md Masum Billah while Yuvin
Kokuhennadige completed chapters ‘Business Idea’, ‘Intellectual Property’ and main parts of this
supplement chapter. ‘Product/Service’ section and ‘SWOT-analysis’ section were done by Jaakko
Lind and Joni-Markus Hietanen wrote ‘Market situation and competitors analysis’ and ‘Product
development and technology’ sections.
‘While writing the Business Idea chapter I was able to get an idea of what is important in the
business perspective for our product. Me and my team was able to clearly understand our direct
customers, competitors and how we should aim to generate revenue with our product. Writing the
Intellectual Property chapter taught me different ways we can protect our product. The search for
other similar products already patented led us to discover no similar products exists yet. This gives
us the freedom to develop and market our product without fear of infringing someone else’s work. I
was able to discover what components of our product is patentable and also how we can protect our
brand using a trademark.’ - Yuvin Kokuhennadige
‘Working on the summary chapter gave me an opportunity to understand the overall

business aspects of our product. I was able to differentiate the competitive advantages of our
product. I found the customer demand in the recycling industry and how can a product satisfy their
needs. In addition, I got the ideas about the market size and competitions, our scopes and market
entry strategy. Writing conformance chapter taught me that making a product is not sufficient, but
the product must meet the standard set by the different organizations. I was able to find out which
directives and standards is required for our products to successfully launch it into the market. I
understood which improvements and modification require for our product to meet the global
benchmark.’ - Md Masum Billah
Page 10 of 11
‘The market investigation revealed a lot of options and potential decisions to be made
considering our product. The potential is there, but competition is also fierce. In order to be relevant
within today’s markets, one has to possess a lot of preliminary information and also be capable of
innovation as well as compromise. Competition is also self-defeating without appropriate product
development, which must be constant, cutting-edge and flexible. Also, the road for productizing a
prototype takes up a lot of minor, yet mandatory steps, which I personally had not considered
before.’ - Joni-Markus Hietanen
‘As I was working on the ‘Product/Service topic, I was able to think about the whole
product and the usage of it. This was not too hard as we have been working on this project for quite
a while already. However, I thought about the other things our company should provide to the
customer alongside the actual product. I instantly thought about the services that are usually
provided with the commercial products as I have been working in service department in ABB
before. Also, I got a good reminder how to prepare a SWOT analysis. The hardest part here was to
find the weaknesses and threats of our product. After finding some, I tried to figure out how to
prevent those. This was good learning experience’ - Jaakko Lind
Page 11 of 11

Final Report Project #26 Induction Heater For Melting Aluminum

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Final Report Project #26 Induction Heater For Melting Aluminum

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Aalto University, School of Electrical Engineering

Automation and Electrical Engineering (AEE) Master's Programme

The principle of induction heating is developed based on Faraday’s law of electromagnetic

4. Heating Element Design

4.1. Frequency Selection

4.2. Wire, Insulation and Crucible Selection

Table 2. Graphite crucible specifications.

4.3. Power Transmission

Table 3. Design parameters and transmitted power.

Figure 2. Thermal model of the heating element.

where M is the convection coefficient and N is the cross sectional area.

Table 4. Analytical results of the heating element.

5.1. Power Electronics

5.2. Gate drivers

Figure 5. PLECS simulation of the gate drivers.

6. Reflection of the Project

M1 Planning (Planned deadline: 4.2.2019, Completed on: 1.2.2019)

6.3. Risk analysis

6.4. Project Meetings

6.5. Quality management

fprintf('Calculation of the power transmitted by eddy current in an

fprintf('Outer Tube dimensions:\n\t Outer radius R = %.3g mm\n\t Inner

fprintf('Inner Tube dimensions:\n\t Outer radius Ro = %.3g mm\n\t Inner

fprintf('Magnetic field source:\n\t Amplitude Hs = %.3g kA/m at r=Ro\n\t

% discretization of the raidus

fprintf('Eddy current characteristic\n\t Skin depth in outer tube: %.3g

fprintf('\t Skin depth in inner tube: %.3g mm\n\n', delta_II*1e3);

hz_I = A_I * besseli(0,(1+1j)/delta_I*rI) + B_I *

jphi_I = -(1+1j)/delta_I * A_I *besseli(-1,(1+1j)/delta_I*rI) +

hz_II = A_II * besseli(0,(1+1j)/delta_II*rII) + B_II *

jphi_II = -(1+1j)/delta_II * A_II *besseli(-1,(1+1j)/delta_II*rII) +

% Calculation of the inductance

fprintf('\t Inductor characteristics:\n');

% Display the distrubution of the electro-magnetic quantities

fprintf('Thermal characteristic\n\t Temperature rise : \x0394 T = %.0f

fprintf('\t Fusing temperature of the aluminium : T = 660 \x00B0 C\n');

fprintf('\t Fusing temperature of the steel : T = 1 450 \x00B0 C\n');

fprintf('\t Fusing temperature of the graphite for crucible : T = 3 850

alpha_C=30; %Convection Coefficient

Ral_out=26.65e-3; % Outer radius of Aluminum

Ral=(log(Ral_out/Ral_in))/(2*pi*lam_al*A_L); %Thermal resistance of

n=70; %Number of Strands

%% Thermal Resistances Aluminum Side

TA = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_G*R1*R3 +

TB = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_A*R2*R4 +

TC = (R1*Tamb + R2*Tamb + R3*Tamb + R4*Tamb + P_A*R1*R4 + P_A*R2*R4 +

M2 Conceptualization ​(Deadline: 18.2.2019)

M3 Prototyping ​(Deadline: 18.3.2019)

M4 Subsystem completion ​(Deadline: 15.4.2019)

M5 System completion and integration ​(Deadline: 6.5.2019)

M6 Final delivery ​(Deadline: 20.5.2019)

M7 Presentation ​(Deadline: 21.5.2019)

M8 Project Report ​(Deadline: 31.5.2019)

1. Concept (139 h, 17%)

2. Development (142 h, 18%)

3. Implementation (206 h, 25%)

4. Finalization (66 h, 8%)

5. Documentation ( 192 h, 24%)

hz_I = A_I * besseli(0,(1+1j)/delta_IrI) + B_I

jphi_I = -(1+1j)/delta_I * A_I besseli(-1,(1+1j)/delta_IrI) +

hz_II = A_II * besseli(0,(1+1j)/delta_IIrII) + B_II

jphi_II = -(1+1j)/delta_II * A_II besseli(-1,(1+1j)/delta_IIrII) +

Ral=(log(Ral_out/Ral_in))/(2pilam_al*A_L); %Thermal resistance of

TA = (R1Tamb + R2Tamb + R3Tamb + R4Tamb + P_AR1R4 + P_GR1R3 +

TB = (R1Tamb + R2Tamb + R3Tamb + R4Tamb + P_AR1R4 + P_AR2R4 +

TC = (R1Tamb + R2Tamb + R3Tamb + R4Tamb + P_AR1R4 + P_AR2R4 +

M2 Conceptualization (Deadline: 18.2.2019)

M3 Prototyping (Deadline: 18.3.2019)

M4 Subsystem completion (Deadline: 15.4.2019)

M5 System completion and integration (Deadline: 6.5.2019)

M6 Final delivery (Deadline: 20.5.2019)

M7 Presentation (Deadline: 21.5.2019)

M8 Project Report (Deadline: 31.5.2019)

Table 2. Cost Estimation