ELEKTRONIKA DAYA

SINGLE-PULSE CONVERTER M2CK, OHMIC LOAD

By :

I MADE JAYADI KUSUMA BRATA

5A TL

1715313049

PROGRAM STUDI D3 TEKNIK LISTRIK

JURUSAN TEKNIK ELEKTRO

POLITEKNIK NEGERI BALI

2019
I.TITLE
SINGLE-PULSE CONVERTER E1CK, OHMIC LOAD
II. OBJECTIVES
- Recording voltage and current time profiles
- Voltage and current measurements
- Determination of various characteristic data

III. EQUIPMENTS
- 1 DL 2604 SCR
- 1 DL 2613 Dc power supply
- 1 DL 2614 Voltage reference generator
- 1 DL 2616 Two pulse control unit
- 1 DL 2626 Mains transformer
- 1 DL 2628 Super-fast fuses (3x6.3 A)
- 1 DL 2635 Universal load
- 1 DL 2643 Socket with shunts 1Ω
- 1 DL 2109T3PV Moving-iron voltmeter (125-250-500 V)
- 1 DL 2109T33 True rms meter
- 1 Dual-channel oscilloscope (preferred storage type)
IV. CIRCUIT DIAGRAM
Circuit Diagram:
EXPERIMENT N⁰2A: CONVERTER E1CK, OHMIC LOAD
V. EXPERIMENT PROCEDURE

Assemble the circuit according with the foregoing topographic diagram,

disregarding detail (a) at first.
1) Connection

Connect the voltage reference generator DL 2614 and the control unit
DL2616 to the power supply +15V/0/-15V.
Connect the output Uo of voltage generator to input Uc of the control unit.
Connect the terminals L/N (USYN) of the control unit respectively to
terminals 2V1/2V3 of the mains transformer.
Connect the pulse transformer 4 to gate/cathode circuit of the SCR: socket
marked with a dot to the gate.
2) Basic settings

2.1) Voltage reference generator DL 2614

EXT/INT switch on INT position.
(0/+10V)/(0/+10V) switch on (0/+10V) position.
Setpoint potentiometer to 10 V.
2.2) Control unit DL 2616
Control angle αo switch on 0⁰ position.
“Pulse shape” switch on single pulse position.
Inhibit voltage UINH = 15 V (open).
3) Voltage and current measurements

Supply the circuit and measure:

3.1) the rms value Uv of the supply voltage by the voltmeter P1;
3.2) the average value UdAV and the rms value UdRMS of the direct voltage
by the voltmeter P2;
3.3) the average value IdAV and the rms value IdRMS of the direct current by
the ammeter P3. Enter the measured value as a function of the gate
angle α in 30⁰ steps between 0⁰ and 180⁰ in the following table.
HINT
In order to set the gate angle, set only a half-wave of the direct voltage
with the width of 9 (or 6) grid divisions on the oscilloscope: each division
then corresponds to an angle of 20⁰ (or 30⁰).
 Another system is the use of phase shift αo in the control unit:
1. Set αo = 0⁰ and Uc = 10 V to obtain the firing angle α = 0⁰ ang carry
out the measurements.

2. Set now αo = 30⁰ to obtain the firing angle α o = 30⁰ and, for example,
note down the IdRMS30 value.

3. Set again αo = 0⁰ and adjust Uc in order to obtain IdRMS30 and now set
again αo = 30⁰ in order to obtain the firing angle α o = 60⁰: note down
IdRMS60.

4. Set again αo = 0⁰ and adjust Uc in order to obtain IdRMS60 and now set
again αo = 30⁰ in order to obtain the firing angle αo = 90⁰ and so on.

Uv = 46 V

α(⁰) 0 30 60 90 120 150 180

UdAVα (V)
UdRMSα (V)
IdAVα (A)
IdRMSα (A)
Evaluate the various characteristic data of the converter and compare these
with the theoretical values (see 1.3.1, page 5).

α(⁰) 0 30 60 90 120 150 180

UdAVα (V)
UdRMSα (V)
IdAVα (A)
IdRMSα (A)
Draw the transfer characteristic UdAV/UdAV0 = f(α).
 The referred mean direct voltage value varies as a cosine function in
accordance with equation show in Fig.7, page 7).
The measured transfer characteristic coincides relatively well with the
theoretical curve.
4) Recording on the oscilloscope

Note
Since the basic instrument set does not normally allow simultaneous
measurements, the measures may have to be carried out successively.
4.1. Recording the supply Uv and direct Ud voltages.

Oscilloscope setting
DC coupling; Yt mode; Tigger: AC Line.
Channel 1 (voltage Uv): 50 V/div; probe x10.
Channel 1 (voltage Ud): 50 V/div; probe x10.

Oscillogram (α = 90⁰)

The SCR is turned on when the anode voltage is positive and conduct
immediately after the gate pulse: the section of the positive half-wave
of the supply voltage is transmitted to the load.
4.2. Recording the diode voltage Uv and the direct current Id.

Oscilloscope setting.
 Assemble the measurring circuit according with detail (a).
Channel 1 (Uv voltage): 50 V/div; probe x10.
Channel 2 (current Id proportional to voltage at shunt Rs = 1 Ω):
1V/div; probe x1.

Oscillogram (α = 90⁰)

The negative half-wave of supply voltage is present at the diode as a

reverse voltage as soon as the SCR blocks.
The direct current is in phase with the voltage and the conduction
angle depends on the firing angle.
4.3.Voltage and current time profiles EC1K (α = 90⁰).
VI. EXPERIMENTAL DATA
1) Experimental 1

1. α = 0⁰

- Oscilloscope

2. α = 30⁰

- Oscilloscope :
3. α = 60⁰

- Oscilloscope

4. α = 90⁰

- Oscilloscope :
5. α = 120⁰

- Oscilloscope :

6. α = 150⁰

- Oscilloscope
7. α = 180⁰

- Oscilloscope
2) Experimental 2

1. α = 0⁰

- Oscilloscope

2. α = 30⁰

- Oscilloscope
3. α = 60⁰

- Oscilloscope

4. α = 90⁰

- Oscilloscope

`
5. α = 120⁰

- Oscilloscope

6. α = 150⁰

- Oscilloscope
 7. α = 180⁰

- Oscilloscope

Analysis for the experiment 1.

In this practicum, we are doing two experiment. The experiment is almost

same, the difference with experiment 2 is in the potitioning of the cable that we
use for the osyloscope especially at the CH2. For the change of the degree, we use
the voltage for measuring the degree of this practicum. The maximum voltage in
the board is 10 volt, and then the maximum degree of this practicum is 180
degree. So we use our formula to find how much the voltage to find the degree
30
that we want ( × 10 = 1.6) So every 1.6 volts we got the
180
30 degree.

In this practicum, the yellow wave on the ossiloscope is the source voltage
and the blue wave is the output from the SCR. The shape of the blue wave signal
must be damaged by the changes on the reference voltage generator. This
adjustment is done by increasing the amount of potential resistance, thus
increasing the shooting moment for the gate which will correct the voltage
directly to the Load faster than before. This magnifies the shape of the voltage
output, the blue wave signal, can be seen the SCR output voltage when the
negative half wave is zero. This happens because of the characteristics of the
SCR, reverse bias occurs so that the current is blocked and there is no measured
voltage or zero. when the voltage / angle of the SCR regulator is changed then the
SCR output waveform will change, for example when the voltage controller (knob
potentiometer) SCR is changed to 4.2 v / 90° the value of this voltage is obtained
by the formula α/10 x10v then the voltage will start from the highest point of the
wave because the SCR blocks currents from 0 to 90 and flows back from 90° to
180°.

Analysis for the experiment 2.

For the second practicum, we are doing almost the same step for the step.
The experiment is almost same, but the placement for the probe is different in the
com point. The yellow wave on the oscilloscope (probe 1) is the input voltage and
the blue one (probe 2) is the current from the SCR output. For the change of the
degree, we use the same way in experiment 1, that is we use voltage for measuring
the degree of this practicum. The maximum voltage in the board is 10 volt, and
then the maximum degree of this practicum is 180 degree. So we use our formula
30
to find how much the voltage to find the degree that we want ( × 10 = 1.6)
180
So every 1.6 volts we got the 30 degree.

In probe 2 we can said is measuring current because based on the

following formula v= i/r or it can be said the value of the voltage is the same as
the current because of the use of a 1 ohm resistor. in this experiment when turning
the potentiometer knob there will be a change in the yellow and blue waves, for
example when the potentiometer knob is rotated 90°, on a positive half wave
when it reaches 90° angles the measured voltage is zero, this is because there is no
measurable voltage difference is 0. In the blue wave when the source voltage in
the measured negative half wave current is zero, this is because the SCR blocks
the voltage of the negative wave due to this direction from the anode to the
cathode. actually the voltage still exists but because of this SCR nature the
measured current becomes zero.

VII. CONCLUSIONS
So conclusions can be obtained from the results of experimental data 1 and 2,
including:
1. From the two experiments that distinguish them sin the input if the first input
wave has a stable wave. But in the second experiment, the input wave is
influenced by the voltage reference generator. So the input waveform in the
second experiment is different in each degree.
2 . The value of the voltage reference generator affects the shape of the curve of
the input wave in the second experiment, and affects the shape of the curve of the
output wave in the first and second experiments.
VIII. REFERENCES
http://zonaelektro.net/scr-silicon-controlled-rectifier/
https://www.scribd.com/doc/95739169/Karakteristik-SCR
https://www.wikikomponen.com/jenis-tipe-scr-menurut-bentuk-dan-karakteristik-
bias/