LAYOUT ACADEMY

SOLAR
INVERTER
Production Course

Course Handout
COURSE INSTRUCTOR

OFEGOR COLLINS
CEO FEGGY ENERGY SERVICES LTD
COURSE INSTRUCTOR
SOLAR INVERTER PRODUCTION,
INSTALLATION AND DESIGN

THE INVERTER
This lecture is designed to equip the trainee with
requisite skill on how to produce Inverter for solar
energy. The student will also be opportuned to learn
how to install the complete pack of solar power which
includes solar panel, charge controller and inverter
battery.

AIMS AND OBJECTIVES

This course is aimed at providing the student with the
skill on inverter production in particular and solar
power installation in general. At the end of the training,
the trainee should be able to produce solar power
inverter (1KVA) and then steadily progress to produce
solar inverter of higher capacity

4 COURSE OBJECTIVES
To eradicate the incessant power failure in our
immediate homes
To collectively light up our society
To reduce air and sound pollution emanating from
engines such as fuel and diesel generators
For financial independence and stability
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 COURSE OUTLINE

1. Design and construction of INVERTER

TRANSFORMER

2. Design and construction of OSCILLATOR

3. Design and construction of POWER SOURCE

4. Design and construction of the RELAY CIRCUIT

5. Design and construction of MOSFET CIRCUIT

6. Calculation of MOSFET CIRCUIT

7. Assembling the INVERTER

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 1. THE INVERTER TRANSFORMER
Calculations involved in the design and construction of
the inverter transformer

PARTS OF THE INVERTER TRANSFORMER

a. LAmination Core
b. Bubbin/ Former
c. Copper Coil

CALCULATION OF TRANSFORMER WINDING FOR

1KVA

VT = 0.5 x √kva = (1)

=0.5 x √1
=0.5 x 1
=0.5v per turn
Where VT = Voltage per turn
kva = capacity of inverter to design (eg. 1Kva)

Nv = VD/VT x 1.04 = (2)

Where Nv = No of turns for a particular voltage
VD = Voltage by design
1.04 = Compensation loss

Note: 12v = 1kva

24v = 2kva
36v = 3kva
48v = 4kva
60v = 5kva

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SECONDARY & PRIMARY VOLTAGE

Secondary: 0v, 180v, 200v, 220v, 230v, 240v, etc.

Primary: 0v, 12v, 24v, 36v, 48v, 60v, 72v etc.

NOTE: Nigeria is mainly 0v, 230v, 240v for secondary

voltage.

DESIGN AND CONSTRUCTION OF INVERTER

TRANSFORMER

A transformer step up or down the voltage depending

on the pattern of the connetion

Pri. Voltage
Sec. Voltage
12v 240v (Supply / Live)

Input
0v 230v (charging)

12v
0v (Neutral)
1kva/12v 0v Center-Tap transformer

We first design or wind the side with high voltage

which is the secondary phase/ side.

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WINDING FORMULA FOR 1KVA

VT = 0.5 x √1kva
= 0.5 x √1
= 0.5 volts per turn (V/T)

NV = VD/VT x 1.04 (compensation loss)

FOR SECONDARY VOLTAGE

N0v = 0/0.5 x 1.04 = 0 turns

N230v =230/0.5 x 1.04 = 479 turns
N240v =240/0.5 x 1.04 = 500 turns

FOR PRIMARY VOLTAGE

N0v = 0/0.5 x 1.04 = 0 turns

N12v = 12/0.5 x 1.04 = 25 turns

WINDING FORMULA FOR 2KVA

FOR SECONDARY VOLTAGE

N0v = 0/0.7 x 1.04 = 0 turns

N230v =230/0.7 x 1.04 = 342 turns
N240v =240/0.7 x 1.04 = 357 turns

FOR PRIMARY VOLTAGE

N0v = 0/0.7 x 1.04 = 0 turns

N24v = 24/0.7 x 1.04 = 36 turns

NOTE: For secondary voltage, the number of turns

decreases as inverter capacity (kva) increases while for
primary voltage, the number of turns increases as
inverter size increases.
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 Layout Academy

WEIGHT
INVERTER
COIL GUAGE (POUND) PRI &
(KVA)
SEC

1 - 1.5 19 3.5

2 - 3.5 17 7

4 - 5.5 15 10

6 - 7.5 13 15

8 - 10 11 20

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2. OSCILLATOR CIRCUIT
COMPONENTS
1. 4.7k Resistor .................................... 3

2. 100k Variable Resistor .................................... 1

3. 10uf/50v Capacitor .................................... 1

4. 1k Resistor .................................... 1

5. 47uf/50v Capacitor .................................... 1

6. 100k Resistor .................................... 1

7. 104 Capacitor .................................... 3

8. In4007 Diode .................................... 1

9. 10k Resistor .................................... 2

10. In4148 Diode .................................... 1

11. Bc 547 .................................... 2

12. Bc 557 .................................... 2

13. SG 3524 IC and Socket .................................... 1

14. Veroboard (Line) .................................... 1

15. 9v Battery and Battery Clip .................................... 1

16. Jumper Wire .................................... 1 yard

17. Light Sampaper .................................... 1

18. Razor Blade

19. Cellotape
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DESIGN & CONSTRUCTION OF THE
OSCILLATOR CIRCUIT
Behavior of components & identification.

1. RESISTOR

a. Limits or reduces the flow of current .

b. Variable eg. 104

c. Fixed eg. 4.7k, 1k. 100k, 10k

2. CAPACITOR
a. Filter
Strong Charge
b. Delay

a. A.C or ceramic or paper capacitor

b. D.C/ Electrolytic capacitor

D.C eg. {10uf/50v}

{47uf/50v} short leg Long leg
(No Polarity)
-ve +ve
A.C eg. 104
No +ve
No -ve 8
3. DIODE
To allow current (I) flow in one direction.
a. PN Junction Diode eg In4007
b. Zener Diode eg. In4148

PN - Diode Zener Diode

Forward direction Backward direction

+ - I = Current I + -

4. TRANSISTOR
a. Switch - Streetlight circuit
b. Amplifier - Radio/ TV/ Broadcasting

a. NPN eg. BC 547

b. PNP eg. BC 557

5. SG - 3524 iC DC AC (Frequency) = 50Hertz (50Hz)

Reference Point

Curve
007

16 Pins iC
Sg - 3524 iC
Socket
(sg 3524)

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 OSCILLATOR CIRCUIT DRIVE CIRCUIT

Bring out the

12v DC Battery/
input terminals
Pin 15 (+)
pin 15 (+) and
104
pin 8 (-)
+

In400 7
Output
-
terminals pin 11 Pin 8

& pin 14 C
BC547 (1)
up 4.7k c B
E
c To mosfet
c Gate 1
E
10k C
1k B BC557 (2) BC547 (3)
S9-3524iC Arb 12 B
C
10k E
2 Arb 10 Pin 8
100k V.R 100k c To mosfet
Gate 2
104
E
B BC557 (4)
In 4148 C

4.7k
arb - 13
down
10uf/50v
104

Pin 8 (-)
Pin 8
Pin 8/and/-ve 12v Battery

Pin 8

(+) of 10uf/50v capacitor at arbitrary point

47/uf/40v Capacitor
(+) to pin 2, (-) to pin 5

Pin 4 & 5
Pins 4 and 5 are connected with the help of a jumper
wire

100k Resistor and 100k variable Resistor

One leg to pin 6, separate it from the other leg,
which meets with leg 3 of the 100k variable resistor
at line 6, while legs 1 and 2 of the 100k variable
resistor go to pin 5 7
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104 Capacitor (3)
One leg to pin 7, the other leg to pin 5
One leg to pin 16, the other leg to pin 8
One leg to pin 9, the other leg to pin 8

Pin 8
Use jumper to connect pin 8 to pin 5

In4007 Diode
(-) to pin 15, (+) to outside - Pin 15 + terminal

Pin 15, Pin 13 and Pin 12

The Pins 15, 13 and 12 are connected to each other
with the help of a jumper wire

Pin 14
Pin 14 goes straight to the drive circuit

Pin 11
Pin 11 goes straight to the drive circuit

Pin 10 Free

1k, 10k, 100k

Each of their legs meet together at arbitrary point.
The other leg of 10k to pin 8, while the other leg of
the remaining 10 connects with the (-) of In4148
diode at arbitrary point. The (+) of the 4148 diode
goes to pin 9. 7
11
10uf/50v Capacitor
(-) to pin 8, while (+) meets with one leg of 4.7k at
arbitrary point.

Drive Circuit Pin 14

The (BASE) of BC547 and BC557 are linked to pin
14. The Emitter of BC547 and 557 are linked

Pin 11
The BASE of BC 547 and 557 are linked to pin 11.
The emitter of both are also linked
The COLLECTOR of 547 of pin 14 and pin 11 are
linked. While the COLLECTOR of 557 of pin 14 and
pin 11 are linked

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 3. DESIGN & CONSTRUCTION OF
POWER SOURCE CIRCUIT
The power source circuit converts A.C to D.C
220/240 AC 12/15v DC

Four (4) Components of power source circuit

1. Transformer (500MA/12-0-12v/3 annoldwire)
2. Bridge Diode (KBL406, KBP206, etc.)/Rectifier
3. Capacitor (470uf/50v)
4. Voltage Regulator [L78(12) (v or L78(15)v]

Schematic Diagram Of Power Source

220v Primary Secondary 12v Bridge Diode Capacitor Voltage Regulator

470uf L7812
KBP206
50v CV
+ -
Input 0v i G O
+ve -ve + - +
c +12
DC
c
c

0v 12v -12
DC
Output

4. DESIGN AND CONSTRUCTION OF

RELAY
Schematic Diagram Of A Relay/ Electronic
Representation
Normally Open
Coil 1 COM
Coil 1 NOX 2

Common
COM COM 30A/22Vac - NO
220A/220Vac - NC
NC
Normally Closed
Coil 2
NC
Coil 2 NOX

A Relay is an automatic power switch 7

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5. DESIGN AND CONSTRUCTION OF
THE MOSFET CIRCUIT
MOSFET is defined as an automatic power switch. It is
used in the inverter system to switch the high current
coming from the battery through the transformer
primary winding
With Current rating

FUNCTIONS Irfp = 40A =Im Irfp

150N 150N
Switch DC to AC
Change AC to DC
alt
D S
G
Sou rce
Gat e

Dra in

10k1/4watts

1k1/2watts

How To Calculate The Number Of Mosfets For A

Typical Inverter (e.g. 1kva/12v)
Note, In this inverter being constructed, the
Input/ Primary Voltage =12v =V1
Inverter Capacity 1kva = 1000Va = Power =P
Since P = I1V1
I1 = p/V1 = 1000Va/12v = 83.3 Amps
This is also to know the minimum capacity of battery that will power the inverter

No. of Mosfets MN = I1/Im = 83.3A/40A = 2.08 =

3mosfets
Because the mosfet circuit works for 24 hours, It's necessary we
double the approximated number of mosfets so as to get the
required number of mosfet for each half cycle or half arm.
i.e. 6 mosfets at each arm

1st Arm

2nd Arm 7
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 Continuity
Gate1 or 2

1k1/2 watts
10k1/4watts

Source
e Source
urc
So Gate
n
ai
Dr

10 k1 /4w att s
1k1/2watts

Gate
Source
Drain
Drain/ Earth - 1 or 2
Drain
Note: Gate is 1 and 2
Source is 1
Drain is 1 and 2

MOSFET MATERIALS
1. Irfp150n - mosfet
2. Ample Bar
3. 1k1/2 watts
4. 10k1/4 watts
5. 16mm cutix cable
6. 4mm cutix cable (single or stranded)
7. Screw/ Bolt/ Washer
8. Cable Lock (16mm)
9. 19 gauge wire (1.5mm)
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Steps Involved In The Final Coupling Of The Inverter
1. Connect the (0v) Center-Tap of the primary side of
the inverter transformer to the +12v (positive) wire
of the battery.
2. Connect Drain 1 and Drain 2 to the upper and lower
arm (12v) of the primary side of the inverter
transformer.
3. Connect the Source of the Mosfet to the
-12(negative) of the battery.
4. Connect the two Gates of the Mosfet (ie. Gate 1 and
Gate 2) to the Pin 11 and Pin 14 Output of the
Oscillator circuit respectively
5. Connect the fuse -1st terminal to the +ve/Live 220v
of the power cable and the fuse -2nd terminal,
which is now your +ve/Live power, connect with: a.
Live of Power Source Transformer input (i.e.
220v/240v). b. Normally closed (N.C) of the RELAY 1
6. Connect the -ve/Neutral of the power cable to
a.Neutral of Power Source Transformer input (0v)
b.0v of the secondary side of the inverter
transformer.
7. Connect Pin 15 of the Oscillator to the 1st terminal
of the power switch and the 2nd terminal of the
power switch to the common (com) of the RELAY 2

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8. Connect pin 8 of the Oscillator to the -12v (negative)
of the battery
9. Connect the Normally Closed (N.C) of the RELAY 2 to
the +12v positive of the battery
10. Connect Coil 1of the RELAY 2 to the output (+) of
Power Source 2
11. Connect Coil 2 of the RELAY 2 to the output (-) of
Power Source 2
12. Connect Input (0v) of Power Source 2 to the (0v) of
Power Source
13. Connect Input (12v) of Power Source 2 to any of the
12v of Power Source Transformer
14. Connect the Common (com) of the RELAY 1 to the
230v (charging) terminal of the Inverter Transformer
15. Connect Coil 1 of the RELAY to the pin 15 of the
Oscillator and coil 2 of the RELAY 1 to the pin 8 of the
Oscillator
16. Connect the +ve (positive) terminal of the inverter
(power L.E.D) with a 1k resistor to the pin 15 of the
oscillator and the -ve(negative) terminal of the inverter
(power L.E.D) to the pin 8 of the Oscillator.
17. Connect the +ve (positive) of the charging L.E.D
with a 1k resistor to the output +ve (positive) of the
power source 1 and the -ve (negative) of the charging
L.E.D to the -ve (negative) of the output Power Source 1
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18. Connect the 240v and 0v of the secondary side of
the inverter transformer to the live and Neutral
terminal of the output socket respectively
19. Connect the AC filter ceramic capacitor
(WFL225j 400v) to the live and Neutral terminal of the
output socket
20. Connect the Bridge Diode Input (i.e. input 0v and
input 12v) of the power source 1 to the 12v-0v-12v (i.e.
0v of the remaining 12v) of the Power Source
Transformer, respectively
21. Connect the A.C Voltmeter (Digital/Analogue) to
the terminals of the output socket
22. Connect the (+) 12v D.C fan to the pin 15 of the
oscillator while the (-) of the D.C fan to the pin 8 of the
Oscillator

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 (Series - Parallel)

1kva/12v 240 A.C

Series Configuration 5 hrs

Par alle l Incr eas es Dire ctio n

12v
100ah

12v 10 hrs
240 A.C 100ah
2kva/24v
300ah/12
12v 15 hrs
12v 10hrs 100ah
12v
24v/200a

100A 100A
48v/4kva 240 A.C

12v/100A
12v/100A
12v/100A 12v/100A 48v/200A
10hrs

12v/100A 12v/100A 12v/100A 12v/100A

LAW : In Ser ies - Vol tag e Add s, Pow

er Sam e
In Par alle l - Vol tag e Sam e, Pow er
Add s

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 Schematic Diagram For Solar Energy Installation

In the above system, the light energy from the sun id

trapped by the solar panel in the D.C form and sent to the
deep cycle battery through a solar charge controller which
helps to regulate the charging process of the battery. This
D.C current stored in the battery is then sent to the input
terminal of the inverter (1kva/12v). The inverter then
converts the D.C current into an alternate current A.C at
240 voltage. This generated A.C output current is what is
needed to power all domestic and industrial appliances we
use in our world today.

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 LOAD ANALYSIS
Energy Bulb (20 watts each x 10 pcs) = 200 watts
Television = 180 watts
Sound System = 150 watts
Fan (70 watts each x 4 pcs) = 280 watts
Iron = 1000 watts
Freezer = 350 watts
Others = 200 watts
2,360 watts
To derive the capacity of the inverter in kva that will power
the above listed devices
kva = watts/800 = 2,360/800 = 2.95 = 3kva

How to calculate the number of battery that will power a

particular inverter already designed

KVA Inverter Battery Voltage (Series) or

Number Of Batteries
Capacity Parellel

1 - 1.5 12 1

2 - 3.5 24 2

4-5 48 4

5.5 - 7.5 96 8

8 - 10 96/120 8/10

15 - 20 192 16

Note: Battery Capacity = Va/Battery Voltage =1000va/12 = 83.3

7
100Anps Battery 21
TOTAL SOLAR INVERTER COMPONENTS ESTIMATED
COST IN NGN

A. Inverter Transformer Components (₦11,000 - ₦14,000)

i. Lamination Core ii. Bubby/Former/Slot iii. Copper Coil

B. Oscillator Circuit Components

Vero board (Line) ₦100 - ₦150
100k variable resistor (V.R) ₦10 - ₦20
100k Resistor ₦5 - ₦10
10k Resistor ₦5 - ₦10
1k Resistor ₦5 - ₦10
104 Capacitor ₦10 - ₦20
4.7k Resistor ₦5 - ₦10
47uf/50v Capacitor ₦30 - ₦50
10uf/50v Capacitor ₦20 - ₦30
In 4007 Diode ₦10 - ₦20
In 4148 Diode ₦10 - ₦20
BC 547 ₦10 - ₦20
BC 557 ₦10 - ₦20
SG3524 iC and Socket ₦200 - ₦300

C. Power Source
500MA 12VAC (3wire Arnold Transformer) ₦600 - ₦700
470uf/50v Capacitor ₦50 - ₦70
Bridge Diode (KBP206 etc) ₦30 - ₦50
Voltage Regulator [L78(12)(v or L78 (15)v)] ₦20 -₦50 7
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D. Relay
Relay 30A/240vac ₦250 - ₦300

E. M.O.S.F.E.T
Irfp150n ₦350 - ₦550
1k Resistor (1/2w) ₦5 - ₦10
10k Resistor (1/4w) ₦5 - ₦10
4mm Cable ₦200 - ₦250 per yard
16mm Cutix Cable ₦450 - ₦600 per yard
16mm Cable Lock ₦50 - ₦100
Plywood ₦1,000
Bolt/Screw/Washer ₦50 - ₦100
19 Guage Wire (1.5mm) ₦100 - ₦150/yard
Angle Bar ₦700 - ₦1000 per length

OTHER COMPONENTS
1/4 China plywood
Hammer (medium size)
AC Ceramic filter capacitor (Wlf 225j400v)
L.E.D (Bulbs)
Power Cable
Lamp holder & bulbs
Jumper wire
Chizel (small/medium)
Nail
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Lead (lmc)
Soldering iron (Souer)
Multi-meter (Mastech MY68)
9v Battery & Clip
12v Battery
Glue gun & Candle
Bolts/Screws/Washers
Paper Sellotape
Razor blade
Magnet
4mm Wire
16mm Flex cable
19 Gauge cable
Wire joiner/ connector
Hand saw (small or medium)
Top Bond
Centi-meter ruler (cm)
Pen/pencil
Drilling machine & drill bits for metal & aluminum pans
Sandpaper soft & hard
Screw driver
Long-nose plier
Normal Plier (medium or big)
Cutter
Sleave
Mica paper
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File
CASTING ARRANGEMENT
Front View
Analogue

1. Voltmeter
Analogue & Digital Power

2. Switch On
Off

3. L.E.D (Light Emitting Diode)

D.C Battery

Back View L -240V

4. A.C Output Socket N - 0V

5. Fuse

6. Main Lead/plug

7. Hole perforation for battery cable

-ve 16mm
+ve 16mm
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