Power Electronics Lab Manual
Department of EEE
Power Electronics
Lab Manual
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Power Electronics Lab Manual
Department of EEE
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Power Electronics Lab Manual
Department of EEE
Instructions to Students Working in Electrical and Electronics Laboratories
Every student should come with right fitting dress & wear shoes with rubber soles.
Every student should avoid wearing metal ornaments like ring, bangles, bracelets, chains etc.
The circuit diagrams should be approved by the Teaching faculty in the laboratory.
The approved indent slip should be given in the store and receive the apparatus box.
These apparatus must be brought from the stores and kept on the worktable in a neat manner,
such a way that the connections are made conveniently.
Make the connections as per the diagram approved.
Get the connections be checked by the Lab Instructor in charge in the laboratory.
The Lab Instructor will arrange to give the supply to the worktable.
After ascertaining, the supply is given to the worktable, and students can proceed to conduct the
experiment as per the instruction issued.
If there is any difficulty experienced in the conduct of the experiment immediately call the Lab
Instructor and get over the difficulty.
After finishing the experiment, switch off the supply, show the observations to the Lab Instructor,
and get approved.
Request the Lab Instructor to make arrangements to switch off the supply to the worktable.
After ascertaining that the supply is switched off, disconnect and return the apparatus box to the
store.
Complete experiment should be recorded in the laboratory record notebook and shown to the
Teaching faculty in the next class.
If there is any damage to any material during transit or conduct of the experiment, all the
students in that particular group/batch are responsible.
Every student should take utmost care not to touch any live points, while they work in the
laboratory.
Every student should keep his/her laboratory record with his/her safely till the concerned practical
examination is over.
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Power Electronics Lab Manual
Department of EEE
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Power Electronics Lab Manual
Department of EEE
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram
V-I Characteristic of SCR
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Power Electronics Lab Manual
Expt.No:
Department of EEE
CHARACTERISTICS OF SCR
Date:
Aim:
To obtain the forward conduction characteristics of the SCR and to measure the holding
current and latching currents.
Apparatus Required:
Sl.No
Name of the Equipment
Model/Range
Quantity
1.
SCR
TYN612
1 no
2.
Ammeter
(0-10mA)MC
1 no
3.
Ammeter
(0-100mA)MC
1 no
4.
Voltmeter
(0-30V)MC
1 no
5.
Bred Board / /Connecting Wires /
Patch chords
as required
Theory:
A SCR is a four layer three terminal semiconductor switching device of PNPN structure with
three PN junctions. The three terminals are anode, cathode and gate. SCRs are manufactured by
diffusion.
When the anode voltage is made positive with respect to cathode, the junctions J1 and J3
are forward biased and junction J2 is reverse biased. A small leakage current flows from anode to
cathode. The thyristor is then said to be in forward blocking or OFF state condition. If V AK is
increased to a sufficient larger value, the reverse biased junction J2 will break. This is known as
avalanche breakdown and corresponding voltage is called forward breakdown voltage (V BO). Now
the device is in ON state. Latching current is defined as the minimum amount of anode current
required to maintain the thyristor in ON state immediately after the thyristor has been turned ON
and the gate signal has been removed. However, if the forward anode current is reduced below a
level known as holding current (IH), a depletion region will develop around junction J2 due to the
reduced number of carriers and the thyristor will be in the blocking state. Holding current is the
minimum anode current required to maintain the thyristor in ON state. Holding current is less than
latching current.
When the cathode is positive with respect to anode, junction J2 is forward biased but
junction J1 and J3 are reverse biased. Now the thyristor will be in reverse blocking state and
reverse leakage current known as reverse current known as I R would flow through the device.
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Power Electronics Lab Manual
Department of EEE
Tabular Column:
Sl.No
IG =
VAK (V)
(mA)
IA (mA)
IG =
VAK (V)
(mA)
IA (mA)
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Power Electronics Lab Manual
Department of EEE
Procedure:
1. Connect the circuit as shown in figure.
2. Switch on the main AC supply
3. Vary the pot3 and set the gate current (4 mA to 5 mA)
4. Slowly increase VAK by varying pot4 till the thyristor gets turned ON. Note down the
ammeter (IA) and voltmeter (VAK) readings.
5. Now note down the forward breakdown voltage and latching current.
6. Further increase VAK and note the anode current
7. Now reduce VAK till the thyristor turned OFF and note down the holding current
8. For various gate current take the readings and tabulate.
9. Plot the graph VAK versus IA.
Result:
Thus the characteristic of SCR is studied and the characteristic curve is plotted.
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram:
V-I Characteristic of TRIAC:
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Power Electronics Lab Manual
Expt.No:
Department of EEE
CHARACTERISTICS OF TRIAC
Date:
Aim:
To obtain the forward and reverse conduction characteristics of TRIAC and to plot its
characteristic curve.
Apparatus Required:
Sl.No
Name of the Equipment
Model/Range
Quantity
1.
SCR study module
TYN612
1 no
2.
Ammeter
(0-10mA)MC
1 no
3.
Ammeter
(0-100mA)MC
1 no
4.
Voltmeter
(0-30V)MC
1 no
5.
Bred Board / /Connecting Wires /
Patch chords
as required
Theory:
A SCR is a unidirectional device as it conducts from anode to cathode only and not from
cathode to anode. A TRIAC can conduct in both directions. A TRIAC is a bidirectional thyristor with
three terminals. It is used extensively for control of power in AC circuits. When in operation, a
TRIAC is equivalent to two SCRs connected in anti-parallel. As the TRIAC can conduct in both
directions, the term anode and cathode are not applicable to TRIAC. Its three terminals are usually
designated as MT1 (main terminal 1), MT2 (main terminal 2) and gate.
With no signal in the gate, TRIAC will block both half cycles of applied voltage in case peak
value of the voltage is less than the break over voltage of the TRIAC. The TRIAC can however be
turned ON in each half cycle of the applied voltage by applying a positive or negative voltage to
MT2 with respect to MT 1.
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Power Electronics Lab Manual
Department of EEE
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Power Electronics Lab Manual
Department of EEE
Procedure:
1. Connect the circuit as shown in figure.
2. Connect MT2 terminal of the TRIAC to positive with respect to MT 1 with positive gate
current
3. Switch on the main AC supply
4. Vary the pot3 and set the gate current (12 mA to 15 mA)
5. Slowly increase VAK by varying pot4 till the TRIAC gets turned ON. Note down the ammeter
(IA) and voltmeter (VAK) readings.
6. Now note down the forward breakdown voltage.
7. Further increase VAK and note the anode current
8. Now tabulate the readings.
9. Plot the graph VAK versus IA.
10. Connect MT2 terminal of the TRIAC to negative with respect to MT 1 with positive gate
current.
11. Repeat the procedure from step 3 to 9
Result:
Thus the forward and reverse conduction characteristics of TRIAC are obtained and they
are plotted.
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram:
Output Characteristics of MOSFET
Transfer Characteristics of MOSFET
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Power Electronics Lab Manual
Expt.No:
Department of EEE
CHARACTERISTICS OF MOSFET
Date:
Aim:
To obtain the steady state output and transfer characteristics of MOSFET and to plot the
same
Apparatus Required:
Sl.No
Name of the Equipment
Model/Range
Quantity
1.
MOSFET study module
TYN612
1 no
2.
Ammeter
(0-100mA)MC
1 no
3.
Ammeter
(0-50mA)MC
1 no
4.
Voltmeter
(0-30V)MC
2 nos
5.
Bred Board / /Connecting Wires /
Patch chords
As required
Theory:
A power MOSFET has three terminals called drain, source and gate in place of
corresponding three terminals collector, emitter and base for BJT. A BJT is a current controlled
device whereas power MOSFET is a voltage controlled device. The control signals are base current
in BJT is much larger than the control signal or gate current required in a MOSFET. This is because
of the fact that gate circuit impedance in MOSFET is extremely high of the order of 109 ohms. This
large impedance permits the MOSFET gate to drive directly from microelectronics circuits. BJT
suffers from secondary breakdown voltage whereas MOSFET is free from this problem.
Power MOSFETs finds application in low power high frequency converters. Two types of
power MOSFETs are there. 1. Enhancement MOSFET 2. Depletion MOSFET. Out of these two types,
n-channel enhancement MOSFET is more common because of high mobility of electrons.
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Power Electronics Lab Manual
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Tabular Column:
Output Characteristics
VGS =
Sl.No
VDS (V)
(V)
ID (mA)
VGS =
VDS (V)
(V)
ID (mA)
Transfer Characteristics
VDS =
Sl.No
VGS (V)
(V)
ID (mA)
VDS =
VGS (V)
(V)
ID (mA)
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Power Electronics Lab Manual
Department of EEE
Procedure:
Output Characteristics
1. Connect the circuit as shown in figure.
2. Switch on the main AC supply
3. Vary the pot1 and set the gate source voltage (V GS)
4. Slowly increase VDS by varying pot2 till the MOSFET gets turned ON. Note down the
ammeter (ID) and voltmeter (VDS) readings.
5. Further increase VDS and note down the drain current
6. For different values of gate source voltage (V GS), note down VDS and ID.
7. Plot the graph VDS versus ID for various VGS.
Transfer Characteristics
1. Connect the circuit as shown in figure.
2. Switch on the main AC supply
3. Vary pot2 and set the drain source voltage (VDS)
4. Slowly increase VGS by varying pot1 till the MOSFET gets turned ON. Note down the
ammeter (ID) and voltmeter (VGS) readings.
5. Further increase VGS and note down the drain current
6. For different values of drain source voltage (V DS), note down VGS and ID.
7. Plot the graph VGS versus ID for various VDS.
Result:
Thus the steady state output and transfer characteristics of MOSFET are studied and the
characteristics curves are plotted.
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram:
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Power Electronics Lab Manual
Expt.No:
Department of EEE
CHARACTERISTICS OF IGBT
Date:
Aim
To obtain the steady state output and transfer characteristics of IGBT and to plot the same
Apparatus Required:
Sl.No
Name of the Equipment
Model/Range
Quantity
1.
IGBT study module
1 no
2.
Ammeter
(0-100mA)MC
1 no
3.
Ammeter
(0-50mA)MC
1 no
4.
Voltmeter
(0-30V)MC
2 nos
5.
Bred Board / /Connecting Wires /
Patch chords
as required
Theory:
A power IGBT has terminals called emitter, collector and gate. This device combines into it
the advantages of both MOSFET and BJT. So an IGBT has high impedance like MOSFET and low on
state power loss like BJT. Further IGBT is free from secondary breakdown problem present in BJT.
IGBT is also known as Metal Oxide Insulated Gate Transistor (MOIGT) or Conductively Modulated
Field Transistor (COMFET).
In forward direction, the shape of the output characteristics is similar to that of BJT. But
here the controlling parameter is the gate emitter voltage (V GE) because IGBT is a voltage
controlled device. The transfer characteristic of IGBT is identical to that of power MOSFET.
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Power Electronics Lab Manual
Department of EEE
Tabular Column:
Output Characteristics:
Sl.No
VGE =
VCE (V)
(V)
IC (mA)
VCE (V)
VGE =
(V)
IC (mA)
(V)
IC (mA)
VGE (V)
VCE =
(V)
IC (mA)
Transfer Characteristics:
Sl.No
VCE =
VGE (V)
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Power Electronics Lab Manual
Department of EEE
Procedure:
Output Characteristics:
1. Connect the circuit as shown in figure.
2. Switch on the main AC supply
3. Vary pot1 and set the gate emitter voltage (V GE)
4. Slowly increase VCE by varying pot2 till the IGBT gets turned ON. Note down the ammeter
(IC) and voltmeter (VCE) readings.
5. Further increase VCE and note down the collector current
6. For different values of gate emitter voltage (V GE), note down VCE and IC.
7. Plot the graph VCE versus IC for various values ofVGE.
Transfer Characteristics:
1. Connect the circuit as shown in figure.
2. Switch on the main AC supply
3. Vary pot2 and set the collector emitter voltage (V CE)
4. Slowly increase VGE by varying pot1 till the IGBT gets turned ON. Note down the ammeter
(IC) and voltmeter (VGE) readings.
5. Further increase VGE and note down the collector current
6. For different values of collector emitter voltage (V CE), note down VGE and IC.
7. Plot the graph VGE versus IC for various values of VCE.
Result:
Thus the steady state output and transfer characteristics of IGBT are studied and the
characteristics curves are plotted.
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram:
With R Load
With RL-LOAD
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Power Electronics Lab Manual
Expt.No:
Department of EEE
HALF CONTROLLED BRIDGE RECTIFIER
WITH R-LOAD, RL-LOAD
Date:
Aim
To study the operation of single phase half controlled bridge converter with R and RL load
and to determine rectification ratio, form factor and ripple factor
Apparatus Required:
Sl.No
Name of the Equipment
Quantity
1.
Single phase SCR module
1 no
2.
Firing module
1 no
3.
CRO
1 no
Formulae:
R-Load
1. Average output voltage
Vdc 
Vm
(1  cos  ) V



2. RMS output voltage
3. Rectification ratio =

4. Form Factor (FF) =
5. Ripple factor =
Vrms

1/ 2
 1 
sin 2 
 Vm      
 V
2 
 2 
Vdc
2Vm / 
Vrms
V dc
FF 2  1
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Power Electronics Lab Manual
Department of EEE
Model Graphs:
Input Voltage Waveform:
Output Voltage waveform:
For R-Load
For RL-Load
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Power Electronics Lab Manual
Department of EEE
RL-Load:
1. Average output voltage
Vdc 


2. RMS output voltage

V
Vm 
rms
2
3. Rectification ratio =

4. Form Factor (FF) =
5. Ripple factor =
Vm
(cos   cos  ) V


1 / 2
1

(    )  (sin 2  sin 2 ) 
V



 
2
Vdc
2Vm / 
Vrms
V dc
FF 2  1
Where,
Vm – Maximum value of supply input voltage
Vm  Vs 2 volt
Vs – Supply RMS voltage
α- Firing angle in degrees
β – Extinction angle in degrees
Note: the values of α, β and Л are in radians in the places (β-α) and Л-α
Theory:
Diode rectifiers provide a fixed DC output voltage and controlled rectifiers give a variable
DC output voltage from a fixed AC supply. The output voltage of the phase controlled rectifiers is
varied by varying the firing angle of thyristors. A phase controlled thyristor is turned on by applying
a short pulse to its gate and turned off due to natural commutation.
Phase controlled rectifiers are simple and less expensive and the efficiency of these
rectifiers are normally above 90%. Phase controlled rectifiers can be classified into two types
depending on the supply: 1. Single phase converters 2. Three phase converters. Each type can be
subdivided into a) semi converter b) full converter c) dual converter. A semi converter is a two
quadrant converter and the polarity of the output voltage can be either positive or negative.
However, the polarity of the output current is always positive.
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Power Electronics Lab Manual
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Tabular Column:
FOR R-LOAD
Sl.No.
Sl.No.
Firing Angle
(degree)
Firing Angle
(degree)
Voltage per
div
Average
Voltage (V)
Voltage
RMS Voltage
(V)
Time per div
Rectification
Ratio
Time (ms)
Form Factor
Ripple Factor
FOR RL- LOAD
Sl.No.
Sl.No.
Firing Angle
(degree)
Firing Angle
(degree)
Voltage per
div
Average
Voltage (V)
Voltage
RMS Voltage
(V)
Time per div
Rectification
Ratio
Time (ms)
Form Factor
Ripple Factor
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Power Electronics Lab Manual
Department of EEE
FOR R-LOAD:
During the positive half cycle, thyristor T1 and D1 are forward biased and when the thyristor T1 and Diode D1
are fired simultaneously at t
  , the load is connected to the input supply through T1 and D1.
During the negative half cycle, thyristor T3 and D2 are forward biased and when the thyristor T1 is fired
at t
    , the load is connected to the input supply through T3 and D2 and the cycle repeats.
FOR RL-LOAD:
During the positive half cycle, thyristor T1 and D1 are forward biased and when the thyristor T1 and Diode D1
are fired simultaneously at t
  , the load is connected to the input supply through T1 and D1.
During this process, the inductance will get charged when the thyristor is conducting,
During the negative half cycle, thyristor T2 and D2 are forward biased
The load current in the inductor will get discharged through D2 and T1 till β and when the thyristor T2 is fired
at t
    , the load is connected to the input supply through T2 and D2.
Again During this process, the inductance will get charged when the thyristor is conducting,
During the next positive half cycle, thyristor T1 and D1 are forward biased
The load current in the inductor will get discharged through D1 and T2 till β and when the thyristor T1 is fired
at t
 2   , the load is connected to the input supply through T1 and D1 and the cycle repeats.
Procedure:
R-Load
1. Connect the circuit as shown in figure.
2. Give the firing pulses to all the four SCRs.
3. Give the input power supply to the bridge rectifier.
4. Vary the firing angle by adjusting the potentiometer in the firing circuit.
5. Observe the load voltage waveform using CRO.
6. Note down the peak value of output voltage and firing angle.
7. Also note down extinction angle for RL-Load
7. Calculate the average, RMS, rectification ratio, form factor and ripple factor.
8. Repeat procedure 4 to 7 for various firing angles.
Result:
Thus the operation of single phase half controlled bridge converter is studied for R-Load
and RL-Load and its performance parameters are calculated.
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Power Electronics Lab Manual
Department of EEE
Circuit Diagram:
With R Load:
With RL Load:
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Power Electronics Lab Manual
Expt.No:
Department of EEE
FULLY CONTROLLED BRIDGE RECTIFIER
Date:
WITH R-LOAD, RL-LOAD
Aim:
To study the operation of single phase fully controlled bridge converter with R and RL load
and to determine rectification ratio, form factor and ripple factor
Apparatus Required:
Sl.No
Name of the Equipment
Quantity
1.
Single phase SCR module
1 no
2.
Firing module
1 no
3.
CRO
1 no
Formulae:

R-Load

1.
2.
3.
4.

V
Average output voltage Vdc  m (1  cos  ) V



1/ 2


 1 
sin 2 
RMS output voltage Vrms  Vm 
    
 V

2 
 2 
Vdc
Rectification ratio =
2Vm / 
V rms
Form Factor (FF) =
V dc
5. Ripple factor =
FF 2  1

RL-Load
1. Average output voltage
2. RMS output voltage
Vdc

V
rms
V
 m (cos   cos  ) V

Vm 
1




1/ 2

(    )  (sin 2  sin 2 ) 



2
2  

V
Vdc
2Vm / 
V rms
4. Form Factor (FF) =
V dc
3. Rectification ratio =
5. Ripple factor =
FF 2  1
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Power Electronics Lab Manual
Department of EEE
Model Graphs:
Input Voltage Waveform
Output Voltage waveform
FOR R-LOAD
FOR RL-LOAD
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Power Electronics Lab Manual
Department of EEE
Where,
Vm – Maximum value of supply input voltage
Vm  Vs 2 volt
Vs – Supply RMS voltage
α- Firing angle in degrees
β – Extinction angle in degrees
Note: the values of α, β and Л are in radians in the places (β-α) and Л-α
Theory:
Diode rectifiers provide a fixed DC output voltage and controlled rectifiers give a variable
DC output voltage from a fixed AC supply. The output voltage of the phase controlled rectifiers is
varied by varying the firing angle of thyristors. A phase controlled thyristor is turned on by applying
a short pulse to its gate and turned off due to natural commutation.
Phase controlled rectifiers are simple and less expensive and the efficiency of these
rectifiers are normally above 90%. Phase controlled rectifiers can be classified into two types
depending on the supply: 1. Single phase converters 2. Three phase converters. Each type can be
subdivided into a) semi converter b) full converter c) dual converter. A full converter is a two
quadrant converter and the polarity of the output voltage can be either positive or negative.
However, the polarity of the output current is always positive.
FOR R-LOAD:
During the positive half cycle, thyristor T 1 and T2 are forward biased and when the thyristors T 1 and
T2 are fired simultaneously at t
  , the load is connected to the input supply through T1 and T2.
During the negative half cycle, thyristor T 3 and T4 are forward biased and when the thyristors T3
and T4 are fired at t
    , the load is connected to the input supply through T 3 and D4 and
the cycle repeats.
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Power Electronics Lab Manual
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Tabular Column
FOR R-LOAD
Sl.No.
Sl.No.
Firing Angle
Voltage per div
Voltage
Time per div
Time (ms)
(degree)
Firing Angle
Average
RMS Voltage
Rectification
(degree)
Voltage (V)
(V)
Ratio
Ripple
Form Factor
Factor
FOR RL- LOAD
Sl.No.
Sl.No.
Firing Angle
Voltage per div
Voltage
Time per div
Time (ms)
(degree)
Firing Angle
Average
RMS Voltage
Rectification
(degree)
Voltage (V)
(V)
Ratio
Ripple
Form Factor
Factor
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Power Electronics Lab Manual
Department of EEE
FOR RL-LOAD
During the positive half cycle, thyristors T1 and T2 are forward biased and when the thyristors T 1
and T2 are fired simultaneously at t
  , the load is connected to the input supply through T1
and T2.
During this process, the inductance will get charged when the thyristors are conducting,
During the negative half cycle, thyristors T3 and T4 are forward biased
The load current in the inductor will get discharged through T 1 and T4 till β and when the thyristors
T3 and T4 are fired at t
    , the load is connected to the input supply through T3 and T4.
Again During this process, the inductance will get charged when the thyristors are conducting,
During the next positive half cycle, thyristors T1 and T2 are forward biased
The load current in the inductor will get discharged through T 3 and T2 till β and when the thyristors
T1 and T2 are fired at t
 2   , the load is connected to the input supply through T 1 and T2 and
the cycle repeats.
Procedure
R-Load
1) Connect the circuit as shown in figure.
2) Give the firing pulses to all the four SCRs.
3) Give the input power supply to the bridge rectifier.
4) Vary the firing angle by adjusting the potentiometer in the firing circuit.
5) Observe the load voltage waveform using CRO.
6) Note down the peak value of output voltage and firing angle.
7) Also note down extinction angle for RL-Load
8) Calculate the average, RMS, rectification ratio, form factor and ripple factor.
9) Repeat procedure 4 to 7 for various firing angles.
Result:
Thus the operation of single phase half controlled bridge converter is studied for R-Load
and RL-Load and its performance parameters are calculated.
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Department of EEE
Circuit Diagram:
Input and Output Voltage Waveforms
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Power Electronics Lab Manual
Expt.No:
Department of EEE
STEP DOWN CHOPPER USING MOSFET
Date:
Aim:
To obtain the gain characteristics of MOSFET based Buck Converter or Step-down Chopper.
Apparatus Required:
Sl.No
1
Name of the Equipment
Quantity
MOSFET based buck-boost converter
1 no
Trainer module
2
CRO
1 no
3
Patch chords
as required
Formulae:
1. Duty cycle ratio δ = TON / T
2. Output Voltage Vo = δ Vs (V)
Where,
T- Total time for a cycle
T = TON + TOFF (ms)
Vs = Supply DC voltage (V)
Theory:
In Buck converter the output voltage is always less than the input voltage in the same
polarity and is not isolated from the input. The input current for a buck converter is discontinuous
or pulsating due to power switch current that pulses from zero to I 0 every switching cycle. The
output current for a buck power stage is continuous or non pulsating because the output current is
supplied by the output inductor /capacitor combination; the output current never supplies the
entire load current. It’s main applications are in regulated DC power supplies and DC motor speed
control.
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Tabular Column
Input Voltage = 24V DC
Sl.No.
TON (S)
TOFF(S)
Duty Cycle Ratio
Output Voltage (V)
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Procedure:
1. Connect the circuit as shown in figure.
2. Initially keep all the switches (S1,S2,S3,S4) in off position.
3. Initially keep Duty cycle Pot in minimum position.
4. Connect banana connector 24V DC source to 24V DC input.
5. Connect the driver pulse output to MOSFET input.(G to G, S toS)
6. Switch on the main supply.
7. Check the test point waveforms with respect to ground.
8. Switch on the S1 switch and then switch ON S2. (S2=1)
9. Vary the duty cycle Pot and tabulate the TON, TOFF values and output voltage.
10. Draw the graph output voltage Vs duty cycle ratio.
Result:
Thus the gain characteristics of MOSFET based buck converter or step down chopper is
obtained.
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Circuit Diagram:
Input and Output Voltage Waveforms
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STEP UP CHOPPER USING MOSFET
Date:
Aim:
To obtain the gain characteristics of MOSFET based Boost Converter or Step up Chopper.
Apparatus Required:
Sl.No
1.
Name of the Equipment
Quantity
MOSFET based buck-boost converter
1 no
study module
2.
CRO
3.
Patch chords
1 no
as required
Formulae:
Duty cycle ratio δ = TON / T
Output Voltage V o = Vs / (1- δ) (V)
where,
T- Total time for a cycle
T = TON + TOFF (ms)
Vs = Supply DC voltage (V)
Theory:
In boost converter the output voltage is always higher than the input voltage in the same
polarity and is not isolated from the input. The input current for a buck power stage is continuous
or non pulsating because the input current is the same as the inductor current. The output current
for a boost power stage is discontinuous or pulsating because the output diode conducts only
during a portion of the switching cycle. The output
capacitor supplies the entire load current for
the rest of the switching cycle.
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Tabular Column:
Input Voltage = 24V DC,
Sl.No.
TON (S)
Output Voltage = 40V Max.
TOFF(S)
Duty Cycle Ratio
Output Voltage (V)
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Procedure:
1. Connect the circuit as shown in figure
2. Initially keep all the switches (S1,S2,S3,S4) in off position.
3. Initially keep Duty cycle Pot in minimum position.
4. Connect banana connector 24V DC source to 24V DC input.
5. Connect the driver pulse output to MOSFET input.(G to G,Sto S).
6. Switch on the main supply.
7. Check the test point waveforms with respect to ground.
8. Switch on the S1 switch and then switch ON S2. (S2=1)
9.
Set the output voltage at above 24V by using duty cycle Pot.
10. Again increase the duty cycle up to maximum and tabulate theTON, TOFF values and output
voltage.
11. Draw the graph output voltage Vs duty cycle ratio.
Result:
Thus the gain characteristics of MOSFET based boost converter or step up chopper is obtained.
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Circuit Diagram:
Carrier and Reference signal
Control Signals for IGBTs
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Expt.No:
Department of EEE
SINGLE-PHASE PWM INVERTER USING IGBT
Date:
Aim:
To study the operation of single-phase bridge inverter with sinusoidal pulse width modulation
method
Apparatus Required:
Sl.No
1.
2.
3.
4.
5.
Name of the Equipment
Quantity
MOSFET /IGBT study module
Inverter control module
CRO
R-L Load
Patch chords
1 no
1 no.
1 no
1 no.
as required
Formulae:
Modulation Index
Output voltage
m
Ac
Ar
Vo  mVs V
Where,
Vs = input DC voltage (V)
Ar – Amplitude of reference signal
Ac – Amplitude of carrier signal
Theory:
DC to AC converters is known as inverters. The function of an inverter is to change a DC
input voltage to a symmetrical ac output voltage of desired magnitude and frequency. The output
voltage could be variable or fixed frequency. A variable output voltage can be obtained by varying
the input DC voltage and maintaining the gain of the inverter constant. On the other hand, if the
DC input voltage is fixed and it is not controllable, a variable voltage can be obtained by varying
the gain of the inverter, which is normally accomplished by pulse-width-modulation (PWM) control
with in the inverter. The inverter gain can be defined as the ratio of the AC output voltage to DC
input voltage.
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Tabular Column:
Sl.No.
Carrier Wave
Amplitude(V)
Freq.(Hz)
Reference Wave
Amplitude(V)
Freq.(Hz)
Modulation
Output
Index
Voltage(V)
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Inverters are broadly classified into two types (1) Single-phase inverters, and (2) three –phase
inverters. These inverters use PWM control signals for producing the AC output voltage. An inverter
is called voltage –fed inverter (VFI or VSI) if the input Voltage remains constant, a current-fed
inverter (CFI or CSI) if the input current is maintained constant.
A Single-phase bridge inverter consists of four switching devices T1, T2,T3, T4 and the four inverse
parallel diodes D1, D2, D3, D4.The diodes are essential to conduct the reactive current and thereby to
feedback the stored energy in the inductor to the dc source. These diodes are known as feedback
diodes.
Procedure:
1. Connect the circuit as shown in figure.
2. Connect R-L Load as shown in the figure.
3. Connect the gating signals from the inverter control module to the inverter module
through signal cable provided.
4. Connect 24V AC voltage to MOSFET/IGBT trainer.
5. Switch ON the main in both the trainer.
6. Measure the amplitude and frequency of sine wave and carrier triangular wave and
tabulate it. And also adjust sine wave frequency about 50Hz.
7. Connect CRO probe to observe the load voltage and load current waveforms.
8. Draw the graph Vo Vs versus time period.
Result:
Thus the operation of single-phase bridge inverter with sinusoidal pulse width modulation is
studied and the waveforms are plotted.
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SCR Series Inverter:
Waveforms:
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Expt.No:
Department of EEE
SCR SERIES INVERTER
Date:
Aim:
To study the operation of series inverter operation to convert dc input to ac output voltage.
Apparatus Required:
Sl.No
Name of the Equipment
Quantity
1.
Series series inverter study module
1 no
2.
RPS
1 no.
3.
CRO
1 no
4.
R Load
1 no.
5.
L Load
1 no.
6.
Patch chords
as required
Theory:
The circuit used for the operation of series inverter is shown in the figure. It is a simple
prototype circuit with many practical applications. The load is connected between a center tapped
choke and a capacitor divider. For the purpose of analysis perfect magnetic coupling is assumed
between the two
of the choke L1 an L2 and the two commutation capacitor C1 and C2 are
assumed to be equal. The dc supply has low internal impedance. The SCR’s are alternatively
triggered from an external circuit, which determines the operating frequency of the inverter. The
resonant frequency is given by
Fo = 1 / 2 ∏ [ 1 / 2 LC – R2 / 4L2 ]1/2
Where L = L1 + L2 Flow the through the load.
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Tabular Column:
No of division
X axis
Y axis
Amplitude
per Div. ( v )
Time per
div( ms )
Amplitude
(v)
Time
( ms )
Frequency
(Hz)
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Procedure:
1. Connect the circuit as shown in figure.
2. Switch ON the main supply.
3. Switch ON the switch ‘S 1’
4. Vary the frequency
5. Connect the CRO Probes and observe the voltage across R.
6. Measure the Amplitude and Time per division for various frequency values.
Result:
Thus the operation of series inverter circuit is studied.
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SCR Parallel Inverter:
Waveforms:
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Expt.No:
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SCR PARALLEL INVERTER
Date:
Aim:
To study the operation of parallel inverter operation to convert dc input to ac output voltage.
Apparatus Required:
Sl.No
Name of the Equipment
Quantity
1
Parallel inverter study module
1 no
2
RPS
1 no.
3
CRO
1 no
4
Lamp Load
1 no.
5
Step down transformer
1 no.
6
Patch chords
as required
Theory:
The circuit of the parallel inverter is shown figure. SCR1 and SCR2 are the main load
carrying SCR’s. The commutating components are L and C. Diodes 1 and 2 permit the load reactive
power to be fed back to the dc supply. These are called feed back diodes. The operation of circuit
is as follows. Consider one half cycle of operation of this circuit,when it is operating in to a
inductive load. Assume that SCR1 is in conduction and that the current has reached a constant
value through it and L. The anode of SCR2 and the right hand plate of C will attain twice the dc
supply voltage E above ground owing to the autotransformer action of T1. Triggering of SCR2
connects C acrossSCR1 in the reverse direction, turning it off. At the same time, voltage 2E is also
applied across choke L. Capacitor C discharges in oscillatory fashion through L, D1, and the
extreme left – hand part of the primary winding of T1. As capacitor C resonantly reverse its charge,
the anode of SCR2 starts to swing negative with respect to ground. This forces diode D2 into
conduction to discharge the energy ( ½ LI 2 ) now stored in L. Current flow now continues through
SCR2., D2 and the extreme right – hand side of the transformer primary, autotransformer action
between sections P3 and P4 serves to return part of the stored energy in L to the dc supply, thus
minimizing losses.
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Tabular Column:
No of division
X axis
Y axis
Amplitude
per Div.
(v)
Time
per div (ms)
Amplitude
(v)
Time
( ms )
Frequency
(Hz)
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With the brief commutating interval complete and SCR1 now turned off, the inductive load
attempts to maintain load current in the direction it had been flowing prior to commutation, for a
period of time depending on the load power factor. During this part of the cycle SCR2 turns off,
and current continues to flow from right to left in the transformer primary, the path now being
section P3 of the primary, the dc source, and D2 this action returns reactive load energy to the dc
supply. When this inductive current reaches zero, SCR2 can again be triggered and current
established in the opposite direction. Through the transformer and load. Now D2 blocks while SCR2
conducts to complete the new half cycle until SCR1 is triggered again.
In order to provide the double triggering necessary for each SCR every half – cycle when
the circuit operates into inductive load, the trigger signal must consist of a series of pulses or a
square wave rather than a single short pulse.
The circuit provides trigger pulses to the SCRs at a frequency around 50HZ. The gating
circuit and inverter power circuit are isolated by a pulse transformer. The circuit takes power for its
operation from the inverter input.
Procedure:
1. Connect 24 V DC to positive and negative end of Input.
2. Connect the Inductor in the place indicated on the circuit.
3. Connect the step up transformer’s primary p1, p2, p3, p4, p5 to p1, p2, p3, p4, p5 indicated on
the circuit.
4. Connect load across the transformer’s secondary s1, s2.
5. Connect the capacitor between p1 and p5.
6. Patch pulse1 (G1 – K1) to SCR 1 and pulse 2 (G2 – K2) to SCR2.
7. The output of transformer is connected to Step down transformer; it is used to see the
waveform in CRO.
8. Switch on the 24 v dc on/off switch.
9. Measure the output voltage and waveform with help of our CRO.
10. The output frequency can be varied by proper tuning of frequency pot.
Result:
Thus the operation of parallel inverter circuit is studied.
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Circuit Diagram:
SCR1
SCR3
AC 230V
Q1
R Load
Q2
SCR2
SCR4
Tabulation:
No of division
X axis
Y axis
Amplitude
Div. ( v )
Time div
( ms )
Amplitude
(v)
Time
( ms )
Frequency
sequence
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Expt. No:
SINGLE-PHASE CYCLOCONVERTER
Department of EEE
Date:
Aim:
To study the operation of single-phase cycloconverter and to observe output waveforms for
different frequency.
Apparatus Required:
1. Cycloconverter kit.
2. Loading rheostat.
3. CRO
4. CRO Probe.
5. Inductor.
6. Connecting wires.
Theory:
The principle of operation of single-phase cycloconverter can be explained with the help of
a circuit. The circuit shown in the figure for obtaining a single phase low frequency output from a
single phase AC input ( 50 Hz.). One group of SCR’s SCR1 and SCR2 produce the positive polarity
of load voltage. SCR1 and SCR2 of positive groups are gated together depending on polarity of
input. Only one of them will conduct when TR1 is positive SCR1 will conduct. Thus in both half
cycles of the input the load voltage will be positive. The SCR will then off by natural commutation
at the end of half cycle of the input. Depending on the desired frequency division, the gating pulse
to the groups SCR will be stopped, SCR3 & SCR4 of negative group will be gated. SCR3 will conduct
whenTR1 is negative and SCR4 will conduct when TR2 is negative. It is used for frequency control
and speed control in induction motor.
Logic to select output frequency:
The frequency selection is obtained by means of 2 binary control switches sw1 & sw2. The
logic is as follows:SW1
SW2
Frequency ( Output )
0
0
50 Hz.
1
0
25
1
1
16.66
0
1
12.5
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Waveforms:
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Procedure:
From the cycloconverter circuit as shown in figure by inter connecting the terminal at the
device module by means of patch cards as indicated below. Connect TR1 to A1,B1 to L1,L2 to
B2,A2 to TR2. Select the desired output frequency by means of binary switch sw1 and sw2
according to logic given.
1. Switch ON AC Power Supply.
2. Release the gating pulse signal to SCR by using the pulse switch.
3. Observe the output voltage waveform on CRO.
4. Take the waveform for different firing angles.
5. Change the output frequency as desired.
6. Observe the voltage waveform.
Result:
Thus the operation of single-phase cycloconverter was studied and waveforms are plotted
corresponding to their frequency.
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Circuit Diagram:
SCR 1
P
230/ 24 V
Triggering
Circuit
AC 230 V
SCR 2
R ’ Load
N
Waveforms:
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Expt. No:
Department of EEE
SINGLE PHASE AC REGULATOR WITH RESISTIVE LOAD
Date:
Aim:
To study the operation of single phase AC regulator with resistive load.
Apparatus Required:
1. Device module.
2. Bridge firing circuit Module.
3. Resistive load.
4. CRO.
5. CRO Probe.
6. Connecting wires.
7. 230 V/24 V step down transformer
Theory:
The AC regulator are used to obtain a variable AC output voltage from a fixed AC source. A
single phase AC regulator is shown in the figure. It consists of two SCRs connected in anti parallel (
back – to – back ). Instead of two SCRs, a triac may be used.
The operation of the circuit is explained with reference to Resistive load. During positive
half cycle SCR1 is triggered into conduction at a firing angle delay of α . The current raises slowly
and reaches zero at 180 ˚.
As long as SCR1 conducts, conduction drop across it, will reverse bias SCR2. Hence SCR2
will not turn on even if gating signal is applied. SCR2 can be triggered into conduction during
negative half cycle after SCR1, turns off. So the output waveform available from 180 +
to 360
degree .The relevant waveforms are shown in figure.
Procedure:
Use any two SCRs in the Device Module, and follow the steps given below.
1. Connect the Two SCRs in anti parallel as shown in figure. Connect the anode of SCR1, to
the cathode of SCR2. Connect the cathode of SCR1 to the anode of SCR2.
2. Connect the Resistive load shown in figure. Connect 24V AC to the circuit using patch
cords.
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Tabulation:
No of division
X axis
Y axis
Amplitude/
Div. ( v )
Time/Div
( ms )
Amplitude
(v)
Time
( ms )
Firing angle
In degree
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3. Connect the gating signals ( G1,K1) from the triggering circuit to SCR1 and (G2 K2 ) to
SCR2.
4. Switch ON 24V supply.
5. Connect the CRO Probes to observe the load voltage waveforms.
6. Take readings for different firing angles.
Result:
The operation of AC voltage regulator with Resistive load is studied and output waveforms
are drawn.
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Circuit Diagram:
P
SCR1
SCR3
M
N
SCR2
SCR4
203V/24 V
Model Graph:
Speed in RPM
Armature Voltage
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Expt. No:
Department of EEE
SPEED CONTROL OF PMDC MOTOR
Date:
Aim:
To study speed control of a dc motor by varying supply voltage through phase controlled
converter.
Apparatus Required:
1. Device module and bridge firing circuit.
2. D.C.Motor.
3. D.C.Voltmeter.
4. Tachometer.
5. 230 V/ 24V step down transformer.
Theory:
The speed of a dc motor can be controlled by varying the applied voltage to the
armature. The armature voltage can be varied by using a single-phase fully controlled bridge
converter. This method is simple ,economical and is used in many industrial applications. By
varying the firing angle of the SCRs the armature voltage is varied and speed is varied.
Procedure:
1. Connect the circuit as per the circuit diagram.
2. Connect voltmeter across the output to measure voltage given to motor.
3. Switch on the supply and to firing circuit.
4. By varying the firing angle ,take voltmeter reading and measure corresponding speed .
5. Draw the graph between speed and voltage.
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Tabulation:
Sl.No.
Voltage
Speed In RPM
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Result:
The speed of PMDC Motor is controlled by using phase-controlled converter.
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Circuit Diagram:
P
A
P
24 – AC
K
UJT
FIRING
CIRCUIT
24V/AC
N
‘R’ Load
N
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Expt. No:
Department of EEE
UJT FIRING CIRCUIT
Date:
Aim:
To study the operation of the UJT Firing Circuit.
Apparatus Required:
1. UJT Firing circuit kit.
2. CRO.
3. CRO Probe.
4. Connecting Wires.
5. Load rheostat.
Theory:
UJT is used as the gate trigger source in SCRs application. The UJT trigger circuit
gives synchronized pulses to trigger two SCRs simultaneously. Here the firing angle can be varied
from 30˚ to 170˚.
Procedure:
1. Connect cathode of SCR to one end of load rheostat.
2. Connect 24 V dc supply across anode of SCR and other end of load rheostat.
3.Connect 24-v dc supply to UJT firing circuit and connect output (G, K) to cathode and Gate of
SCR.
4.Connect CRO across load rheostat.
5.Switch on the power supply to kit and CRO.
6.Observe the output waveform and measure the firing angle ( α = 30 o to 1700).
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Tabulation:
No of division
X axis
Y axis
Amplitude/
Div. ( v )
Time/Div
( ms )
Amplitude
(v)
Time
( ms )
Firing angle
in degree
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Result:
The operation of the UJT triggering circuit is studied and output waveforms are drawn.
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POWERSIM
Introduction:
PSIM1 is simulation software specifically designed for power electronics, motor drives, and
power conversion systems. With fast simulation speed and friendly user interface, PSIM provides a
powerful simulation environment to meet your simulation and development needs.
PSIM includes the basic package, as well as the following add-on options:
Motor Drive Module: It provides built-in electric machine models and mechanical load models
for motor drive system studies.
Digital Control Module: It provides discrete elements such as zero-order hold, z-domain transfer
function blocks, quantization blocks, digital filters, for digital control
system analysis.
SimCoupler Module: It provides interface between PSIM and Matlab/Simulink2 for cosimulation.
Thermal Module: It provides the capability to calculate semiconductor devices losses.
Renewable Energy Package:It includes the basic PSIM package, the Motor Drive Module, and
Renewable Energy models (including solar modules and wind turbine
models) for simulation in renewable energy applications.
SimCoder3 Module: It provides the automatic code generation capability.
TI F28335 Target: It provides function blocks for automatic code generation for TI F28335
DSP.
MagCoupler Module: It provides interface between PSIM and the electromagnetic field analysis
Software JMAG4 for co-simulation.
MagCoupler-RT Module: It provides the link between PSIM and JMAG-RT4 data files.
ModCoupler5 Module: It provides the link for co-simulation between PSIM and ModelSim6.
In addition, PSIM links with the software SmartCtrl5 for control loop design. SmartCtrl is designed
specifically for power converter applications, and is very easy to use. For more information on SmartCtrl,
please refer to SmartCtrl User’s Guide.
With SmartCtrl, PSIM, and SimCoder/ModCoupler for DSP/FPGA targets, Powersim provides a complete
Platform from design to simulation, to hardware implementation.
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PROCEDURE TO DRAW THE CIRCUIT USING PSIM SOFTWARE
STEP 1: Enter into the PSIM platform by doing right click on PSIM as below:
STEP 2: For opening the new file in PSIM,click the file option select new
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STEP 3: New PSIM file will open like this. You can draw the circuit in this file for simulation and also you
can save the same by choosing the save option.
STEP 4: In view option select the library browser as follows:
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Library Browser screen:
STEP 5:one more option to select the components as follows
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To select the various sources click the option Sources
STEP 6: For entering the values of the sources, circuit components etc; do right click on the particular
element. You will get the label as below. You can enter values in that label, appearing on the screen.
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STEP 7: After drawing the circuit, enter the values of various circuit components, save it. To run the
simulation, select the simulation option as below:
STEP 8: Select the SIMVIEW option to see the results.
Example: Single phase half wave converter circuit
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After run simulation, add the results parameters have to be displayed by selecting Add or Add All
options and click ok in the below screen.
Select SIMVIEW to see the results, SIMVIEW displays the waveforms as below:
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SINGLE PHASE HALF CONTROLLED BRIDGE CONVERTER
MODEL GRAPH:
FIRING ANGLE 30·
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Expt. No:
Department of EEE
SIMULATION OF SINGLE PHASE SEMICONVERTER
Date:
AIM:
To simulate single phase semiconverter using PSIM professional.
OBJECTIVE:
A single phase semiconverter uses two thyristors and two diodes, and is commonly used in many
industrial applications. A single phase semiconverter with one thyristor and one diode in each leg is
called single phase symmetrical semiconverter. The other configuration using two thyristors in one leg
and two diodes in other leg is called as a single phase asymmetrical semiconverter.
The semiconverters can be used in applications where only first quadrant application is required.
In this only two thyristors were employed namely T1and T2 in the upper arm are in positive group. The
lower arm consists of
consists of D1 and D2. During positive half cycle T1 and D2 conducts and during
negative half cycle T2 and D1 conducts.
TOOLS USED:
PSIM Professional software
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SEQUENCE OF STEPS FOR SIMULATION:
1. Open PSIM software.
2. Create a new file from file menu.
3. Choose the required components as per the circuit diagram.
4. Place all the components in the new file.
5. Give the suitable parameters for all the components.
6. Connect all the components as per the circuit diagram and save the file.
7. Place the simulation control in the schematic and set the simulation time.
8. Run the simulation and run the waveform display program-SIMVIEW.
RESULT:
Thus the simulation of single phase semiconverter was done using PSIM tools and results were
verified.
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SINGLE PHASE FULLY CONTROLLED BRIDGE CONVERTER WITH R LOAD
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Date:
Expt. No:
SIMULATION OF SINGLE PHASE FULLY CONTROLLED
CONVERTER WITH R RL AND RLE LOAD
AIM
To simulate single phase fully controlled converter with RL and RLE load using
PSIM simulation
software.
OBJECTIVE
The single phase full converter consists of four thyristors namely T1,T2,T3 and T4.During positive
half cycle T1,T2 are forward biased, these two thyristors are fired simultaneously at ɷ t=α, therefore the
load gets connected to the input supply through these thyristors T1,T2.
If the load is resistive the pair of conducting thyristors will turn off exactly at the zero load voltage
for each half cycle. If the load is inductive in nature. Then there will be a negative clipping till ɷ t=Π+α.
TOOLS USED
PSIM professional software.
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MODEL GRAPH
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EXPREESION FOR THEORETICAL CALCULATION:
FOR RL LOAD WITHOUT FREEWHEELING DIODE
Average output voltage vo=
Average output current I0
FOR RLE LOAD
Vo= I0R+E
RMS value of output voltage for RL ,RLE
vrms =Vm / root 2
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SINGLE PHASE FULLY CONTROLLED BRIDGE CONVERTER WITH RL LOAD
MODEL GRAPH
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SINGLE PHASE FULLY CONTROLLED BRIDGE CONVERTER WITH RLE LOAD
MODEL GRAPH
RLE LOAD:
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SEQUENCE OF STEPS FOR SIMULATION
1. Open PSIM software.
2. Create a new file from file menu.
3. Choose the required components as per the circuit diagram.
4. Place all the components in new file.
5. Give suitable parameters for all the components.
6. Choose the suitable gate pulse for each thyristors according to the firing angle.
7. Connect all the components as per the circuit diagram and save the file.
8. Place the simulation control and run the simulation. show the waveform from SIMVIEW.
RESULT
Thus the simulation of single phase fully controlled converter with RL and RLE load is done using
PSIM tools and the results has been verified.
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3 PHASE FULL CONTROLLED CONVERTER WITH R LOAD
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Date:
Expt. No:
SIMULATION OF THREE PHASE FULLY CONTROLLED CONVERTER
AIM:
To simulate three phase fully controlled converter using PSIM simulation software.
OBJECTIVE:
Three phase converters are extensively used in industrial applications upto 120KW level, where a
two quadrant operation is required. In a three phase fully controlled converter the thyristors are fired at
an interval of
/3. The frequency of output ripple voltage is 6fs and the filtering requirement is less
compare to half wave converters.
During the circuit operation, at
Thyristor T1 is made to turn on. The Thyristor firing
sequence will be T1T2, T2T3,T3T4,T4T5 ,T5T6.
TOOLS USED:
PSIM Professional Software.
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WAVEFORM:
Department of EEE
3 PHASE FULL CONTROLLED CONVERTER WITH R LOAD
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EXPRESSION FOR THEORETICAL CALCULATION:
The average output Voltage Vo=
.
The average load current Io =
The rms value of output voltage, Vrms = Vm(3/2pi)^1/2 (pi/3+(3/2)cos 2alpha)^1/2
SEQUENCE OF STEPS FOR SIMULATION:
1. Open PSIM Software.
2. Create a new file from file menu.
3. Choose the required components as per the circuit diagram.
4. Give the suitable parameters for all the components.
5. Choose the suitable gate pulse for each Thyristor according to the firing angle.
6. Place the simulation control in the schematic and set the simulation line.
7. Run the simulation engine and display the waveform.
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RESULTS OBTAINED FROM SIMULATION:
S.NO
PARAMETER
THEORETICAL VALUE
SIMULATION VALUE
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RESULT:
Thus the simulation of the three phase fully controlled converter is done using PSIM tools and
the results has been verified.
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SIMULATION OF SINGLE PHASE AC VOLTAGE CONTROLLER WITH R LOAD
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Date:
Expt. No:
SIMULATION OF SINGLE PHASE AC VOLTAGE CONTROLLER
AIM:
To simulate single phase ac voltage controller using PSIM software.
OBJECTIVE:
AC voltage controllers are thyristor based devices which convert fixed alternating voltage to
variable without a change in the frequency. During positive half cycle of input voltage, the power flow is
controlled by varying the delay angle of thyristor T1, and the thyristor T2 controls the power flow during
negative half cycle of input voltage. The firing angles are kept 180˚ apart.
TOOLS USED:
PSIM professional software.
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MODEL GRAPH: SINGLE PHASE AC VOLTAGE CONTROLLER WITH R LOAD
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EXPRESSION FOR THEORTICAL CALCULATION:
The average value of the output voltage is given by,
Vo= Vs{(1/Π)*((Π-α)+(sin 2(α/2))}^(1/2)
Where
Average output voltage
AC supply voltage
THEORETICAL CALCULATION
The average value of the output voltage is given by,
SEQUENCE OF STEPS FOR SIMULATION:
1.
Open PSIM software. Create a new file from file menu.
2.
Create a new file from file menu.
3.
Choose required components as per the circuit diagram.
4.
All components are connected as per the circuit diagram and save file.
5.
Chose the suitable gate pulse for each thyristor and place the simulation control in the
schematic.
6.
Place simulation control, set time and start simulation and show waveform in scope.
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SINGLE PHASE AC VOLTAGE CONTROLLER WITH RL LOAD
MODEL GRAPH:
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RESULT OBTAINED FROM SIMULATION
R LOAD R=100Ω, α =30˚
S.NO
PARAMETER
THEORETICAL VALUE
PRACTICAL VALUE
RL LOAD R=100Ω ,L= 500mH, α =30˚
S.NO
PARAMETER
THEORETICAL VALUE
PRACTICAL VALUE
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RESULT:
Thus the simulation of single phase ac voltage controller was done by using PSIM and the results
were verified.
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