1

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

A Manual

for

POWER ELECTRONICS LABORATORY

ELECTRICAL CIRCUIT LABORATORY

www.eeecube.com

www.eeecube.com

2

Name ------------------------------------------------------------------------------------------------------------

Reg. No.---------------------------------------------------------------------------------------------------------

Semester------------------------------------------------Year --------------------------------------------------

CERTIFICATE

Certified that this is the bonafide record of work done by the above student in

the -------------------------------------------------------------------------------------Laboratory during

the year 20 - 20

SIGNATUKRE OF HEAD OF THE DEPARTMENT SIGNATURE OF LAB IN-CHARGE

Submitted for the Practical Examination held on -------------------------

External Examiner Internal Examiner

www.eeecube.com

www.eeecube.com

3

LIST OF EXPERIMENTS (Syllabus)

EE 2304 - Power Electronics Lab (Regulation 2008)

1. CHARACTERISTICS OF SCR

2. CHARACTERISTICS OF TRIAC

3. CHARACTERISTICS OF MOSFET

4. CHARACTERISTICS OF IGBT

5. SINGLE PHASE SEMI CONVERTER

6. SINGLE PHASE FULLCONVERTER

7. TRANSIENT CHARATRISTICS OF SCR

8. TRANSIENT CHARACTERISTICS OF MOSFET

9. MOSFET BASED STEP-DOWN CHOPPER

10. MOSFET BASED STEP - UP CHOPPER

11. SINGLE PHASE IGBT-BASED PWM INVERTER

12. THREE PHASE IGBT-BASED P.W.M INVERTER

13. RESONANT DC-DC CONVERTER

www.eeecube.com

www.eeecube.com

4

CONTENT

S.No. Date Experiment Name Marks Staff

Sign

1 CHARACTERISTICS OF SCR

2 CHARACTERISTICS OF TRIAC

3 CHARACTERISTICS OF MOSFET

4 CHARACTERISTICS OF IGBT

5 SINGLE PHASE SEMI CONVERTER

6 SINGLE PHASE FULLCONVERTER

7 TRANSIENT CHARATRISTICS OF S C R

8 TRANSIENT CHARATRISTICS OF MOSFET

9 MOSFET BASED STEP-DOWN CHOPPER

10 MOSFET BASED STEP-UP CHOPPER

11 SINGLE PHASE IGBT P.W.M INVERTER

12 THREE PHASE IGBT P.W.M INVERTER

13 RESONANT DC-DC CONVERTER

Internal Marks Staff in- Charge

www.eeecube.com

www.eeecube.com

5

Expt. No:

Date :

CHARACTERISTICS OF SCR

AIM:

To obtain the Forward VI characteristics of SCR

APPARATUS REQUIRED:

S.NO Name Range Type Quantity

1. SCR - TYN604 1

2. RPS (0-30)V - 2

3. Ammeter (0-15)mA MC 2

4. Voltmeter (0-30)V MC 1

5. Resistor 2.2 KΩ,1KΩ - 1,1

6. Potentiometer 1

7. Bread board 1

8. Connecting Wires As per

requirements

PROCEDURE:

1. Connect the circuit as per the circuit diagram

2. Vary the gate RPS and set the constant value of gate current, Ig

3. Anode power supply is switched ON and it is varied in steps up to breakdown point.

The corresponding changes in voltmeter and ammeter readings are noted.

4. Ig is increased to some value and the same procedure is repeated.

5. V-I characteristics is plotted for observed values.

www.eeecube.com

www.eeecube.com

6

CIRCUIT DIAGRAM:

MODEL GRAPH:

www.eeecube.com

www.eeecube.com

7

TABULATION:

S.No Anode Voltage Va(V) Anode Current Ia(mA)

RESULT:

Thus the forward VI characteristics of SCR have been determined experimentally.

www.eeecube.com

www.eeecube.com

8

Expt. No:

Date :

CHARACTERISTICS OF TRIAC

AIM:

To obtain the VI characteristics of TRIAC

APPARATUS REQUIRED:

S.NO Name Range Type Quantity

1. TRIAC - BT136 1

2. RPS (0-30)V - 2

3. Ammeter (0-50)mA MC 2

4. Voltmeter (0-30)V MC 1

5. Resistor 1.2 KΩ - 2

6. Bread board 1

7. Connecting Wires As per

requirements

PROCEDURE: (FORWARD BIAS)

1. Connect the circuit as per the circuit diagram

2. Vary the gate RPS and set the constant value of gate current, Ig

3. Anode power supply is switched ON and it is varied in steps up to breakdown point.

The corresponding changes in voltmeter and ammeter readings are noted.

4. Forward VI characteristic is plotted for observed values

PROCEDURE: (REVERSE BIAS)

1. Connections as per the circuit diagram.

2. Change the supply terminal to the terminal of TRIAC or MT1 and MT2 are changed.

3. Similar to forward biasing the changes in voltage and current are noted down at a

constant Ig

4. Reverse VI characteristic is plotted for observed values

www.eeecube.com

www.eeecube.com

9

CIRCUIT DIAGRAM:

MODEL GRAPH

www.eeecube.com

www.eeecube.com

10

TABULATION:

FORWARD CHARACTERISTICS:

S.No Anode Voltage Va(V) Anode Current Ia(mA)

REVERSE CHARACTERISTICS:

S.No Anode Voltage Va(V) Anode Current Ia(mA)

RESULT:

Thus the VI characteristic of TRIAC was experimentally verified.

www.eeecube.com

www.eeecube.com

11

Expt. No:

Date :

CHARACTERISTICS OF MOSFET

AIM: To obtain the output characteristics and transfer characteristics of MOSFET

APPARATUS REQUIRED:

S.NO Name Range Type Quantity

1. MOSFET - IRFP 350 1

2. Voltmeter (0-30)V MC 2

3. Ammeter (0-15)mA MC 1

4. Resistor 1 kΩ - 2

5. RPS (0-30)v - 2

6. Bread board 1

7. Connecting Wires As per

requirements

PROCEDURE:

(i )OUTPUT CHARACTERISTICS:

1. Connect the circuit as per the circuit diagram

2. Gate voltage Vgs is kept at a constant value

3. Increase the drain voltage Vds in steps and note down the corresponding values of Id and

Vds

4. Increase Vgs and repeat step (ii)&(ii)

5. Plot the graph between Vds and Id

(ii )TRANSFER CHARACTERISTIS:

1. Connect the circuit as per the circuit diagram

2. Drain voltage Vds is kept at a constant value

3. Change Vgs and note down the corresponding change in Id

4. Plot the graph between Vds and Id

www.eeecube.com

www.eeecube.com

12

CIRCUIT DIAGRAM:

MODEL GRAPH:

www.eeecube.com

www.eeecube.com

13

TABULATION:

OUTPUT CHARACTERISTICS:

S.No Vgs = Vgs = Vgs =

Drain

Voltage Vds(V)

Drain

Current Id(mA)

Vds(V) Id(mA) Vds(V) Id(mA)

TRANSFER CHARACTERISTICS:

Drain Voltage Vds =

S.No Gate Voltage Vgs(V) Drain Current Id(mA)

RESULT:

Thus the output characteristics and transfer characteristics of given MOSFET was

obtained.

www.eeecube.com

www.eeecube.com

14

Expt. No:

Date :

CHARACTERISTICS OF IGBT

AIM: To obtain the output characteristics and transfer characteristics of IGBT

APPARATUS REQUIRED:

S.NO Name Range Type Quantity

1. IGBT Kit - BT126 1

2. Voltmeter (0-30)V mc 2

3. Ammeter (0-15)A MC, MA 1

4. Patch cards As per requir

5. Resistor 1 KΩ - 2

6. Bread board 1

7. Connecting Wires As per

requirements

PROCEDURE:

( i )OUTPUT CHARACTERISTICS:

1. Connection the circuit as per the circuit diagram

2. Take Vgs as the suitable value and keep it as constant

3. Increase VCE in steps and note down the value of Ic respectively

4. Now increase Vge and repeat steps (ii)&(iii)

5. Plot the graph between VCE & Ic

( ii )TRANSFER CHARACTERISTIS:

1. Connect the circuit as per the circuit diagram

2. Take VCE as a suitable value and keep it as constant

3. Increase Vge in step and note down the value of Ic respectively

4. Now increase VCE and repeat step (ii)&(iii)

5. Plot the graph between Vge and Ig

www.eeecube.com

www.eeecube.com

15

CIRCUIT DIAGRAM:

MODEL GRAPH

:

www.eeecube.com

www.eeecube.com

16

TABULATION:

OUTPUT CHARACTERISTICS:

S.No Vge = Vge= Vge=

Collector

Voltage Vce(V)

Collector

Current Ic(mA)

Vce(V) Ic(mA) Vce(V) Ic(mA)

TRANSFER CHARACTERISTICS:

Collector Voltage Vce =

S.No Gate Voltage Vge(V) Collector Current Ic(mA)

RESULT: Thus the output characteristics and transfer characteristics of IGBT was

obtained

www.eeecube.com

www.eeecube.com

17

Expt. No:

Date :

SINGLE PHASE SEMI CONVERTER

AIM:

To hookup the circuit of single phase semi converter and observe the output waveform

across the load for various firing angles.

APPARATUS REQUIRED:

S.NO Name Range Quantity

1. SCR TYN 604 2

2. PN diode 2

3. Load Resistive 1

4. CRO 30MHz 1

5. ASG (0-30)v 1

6. Probe/Power cord 3,2

7. Bread board 1

8. Connecting Wires As per

requirements

9. Trigger unit 1

PROCEDURE:

1. Connect the circuit as per the circuit diagram

2. Connect the trigger pulse across the gate and cathode of thyristor

3. Connect the Resistive load across the output terminal

4. Switch ON the 230V input as supply and step down into 12/24V

5. Vary the potentiometer &observe the output from CRO for output voltage and time

period for various firing angles

www.eeecube.com

www.eeecube.com

18

CIRCUIT DIAGRAM:

MODEL GRAPH:

www.eeecube.com

www.eeecube.com

19

TABULATION:

Firing

Angle(α)

Theoretical

output

voltage(V)

Practical output

voltage(V)

RESULT:

Thus the circuit of single phase semi converter was observed and the output waveform

across the load for various firing angle was observed.

www.eeecube.com

www.eeecube.com

20

Expt. No:

Date :

SINGLE PHASE FULLCONVERTER

AIM:

To hook up the circuit of a single phase full converter and observe the output waveform

across the load for various firing angles

APPARATUS REQUIRED:

S.NO Name Range Quantity

1. SCR TY 6004 4

2. Load Resistive 1

3. CRO 30MHz 1

4. ASG (0-30)v 1

5. Probe/Power cord 3,2

6. Bread board 1

7. Connecting Wires As per

requirements

8. Trigger unit 1

PROCEDURE:

1. Connect the circuit as per the circuit diagram

2. Connect the gate pulse across the gate and cathode of thyristor

3. Connect resistive load across the output terminal

4. Switch ON the 230V supply input as supply and step down to12/24V

5. Vary the potentiometer & observe the output from CRO for output voltage and time

period for various firing angles

www.eeecube.com

www.eeecube.com

21

CIRCUIT DIAGRAM:

MODEL GRAPH:

www.eeecube.com

www.eeecube.com

22

TABULATION:

Firing

Angle(α)

Theoretical

output

voltage(V)

Practical output

voltage(V)

RESULT:

Thus the circuit for single phase fully controlled converter was constructed and the output

waveform across the resistive load for various firing angle was observed and plotted.

www.eeecube.com

www.eeecube.com

23

Expt. No:

Date :

TRANSIENT CHARATRISTICS OF SCR

AIM: To study the transient characteristics of SCR

APPARATUS REQUIRED:

S. No. Apparatus Type/Range Quantity

1.

2.

3.

4.

5.

SCR kit

Ammeter

Voltmeter

RPS

Patch cards

(0-150) mA/MC

(0-600) mA/MC

(0-30) V /MC

(0-30) V

1

1

1

1

As per req.

PROCEDURE:

1. Patch the trainer kit as per the front panel diagram

2. Switch on the trainer and select the sector switch

3. Set +20V of Anode supply voltage in the voltmeter using variable DC supply provided in

the trainer

4. Now, slowly vary gate current (Ig) simultaneously note the values of Ia and Va

5. When the gate current reaches the particular value the breakdown occurs

6. During this turn on period the voltage Va is equal to lower value and the current Ia is

raised to higher value

7. Plot the graph with Va, Ia & Ig by taking Ig on x-axis and Va, Ia, on y-axis.

www.eeecube.com

www.eeecube.com

24

SCR TRANSIENT CHARACTERISTICS

PANEL DIAGRAM:-

CIRCUIT DIAGRAM:-

www.eeecube.com

www.eeecube.com

25

GRAPH :-

TABULATION

S.No Gate Current-IG (A) Anode Voltage Va(V) Anode Current-Ia(mA)

1

2

3

4

5

6

Result: Thus the transient characteristic of SCR was experimentally obtained.

www.eeecube.com

www.eeecube.com

26

Expt. No:

Date :

TRANSIENT CHARACTERISTICS OF MOSFET

AIM:

To study the transient characteristics of MOSFET

APPARATUS RECQUIRED

S. No. Apparatus Range/ type quantity

1

2

3

4

5

MOSFET kit

Ammeter

Voltmeter

RPS

Patch cards

MC(O-15)MA

MC(0-30)V

(0-30)V

1

1

2

1

As per req

PROCEDURE:

1. Patch the Trainer kit as per the front panel diagram.

2. Switch on the Trainer and selects the sector switch.

3. Set +20V of Drain supply voltage in the voltmeter using variable DC supply

provided in the trainer

4. Now slowly vary the Vgs. Correspondingly note down Vds & Id

5. Plot the graph with Vgs on X-axis and Vds & Id on Y-axis

www.eeecube.com

www.eeecube.com

27

MOSFET TRANSIENT CHARACTERISTICS

PANEL DIAGRAM :-

CIRCUIT DIAGRAM :-

www.eeecube.com

www.eeecube.com

28

GRAPH :-

www.eeecube.com

www.eeecube.com

29

TABULATION

RESULT

Thus Transient characteristics of MOSFET were experimentally obtained.

S. No. Vgs(V) Vds(V) Ia(MA)

1

2

3

4

5

6

7

www.eeecube.com

www.eeecube.com

30

Expt. No:

Date :

STEP-DOWN CHOPPER

AIM;

To study the response of a step down chopper (or) buck converter

APPARATUS REQUIRED

1. MOSFET based chopper trainer kit

2. Patch cards

3. CRO

PROCEDURE

1. Connection as per the patching diagram

2. Switch on the main supply

3. Set the carrierwave frequency between 5 KHz to 10 KHz using frequency knob in

the carrier wave generator.

4. Connect CRO across load terminals

5. Vary the duty cycle and observe the output

www.eeecube.com

www.eeecube.com

31

RESPONSE OF STEP DOWN CHOPPER

PANEL DIAGRAM :-

CIRCUIT DIAGRAM & GRAPH:-

www.eeecube.com

www.eeecube.com

32

CALCULATION

Mode 1 => CH – ON (Vs – VL – Vo = o) ( VL = L di/dt)

VL = Vs - Vo (1)

Mode 2 => CH – OFF Vs - Vo = o VL = VO (2)

(Energy conservation principles;-

Energy stored in ‘L’ = Energy discharged in ‘L’

L

VoVsTon )( =

L

VoToff

TABULATION

S.No. Vo

(Practical)

Vi

Ton

(ms)

Toff

(ms)

Vo

(Theoratical)

=Ton/T

1

2

3

4

5

RESULT

Thus the response of step down chopper was experimentally done.

www.eeecube.com

www.eeecube.com

33

Expt. No:

Date :

STEP - UP CHOPPER

AIM

To study the response of step up chopper (or ) boost converter

APPARATUS REQUIRED

1. MOSFET based chopper trainer kit

2. patch cards

3. CRO

PROCEDURE

1. Connection are made as per the patching diagram

2. Switch on the main supply

3. Set the carrier wave frequency between 5 KHZ to 10 KHZ using frequency knob

in the carrier wave generator.

4. Connect CRO across load Resistor terminal

5. Vary the duty cycle knob and observe the variation in the PWM output

www.eeecube.com

www.eeecube.com

34

RESPONSE OF STEP UP CHOPPER

PANEL DIAGRAM :-

CIRCUIT DIAGRAM & GRAPH:-

www.eeecube.com

www.eeecube.com

35

TABULATION

S.No. Vo

(Practical)

Vi

Ton

(ms)

Toff

(ms)

Vo

(Theoratical)

=Ton/T

1

2

3

Example Calculation :

Theortical output voltage

= duty cyue = Ton / T

.

RESULT

Thus study the response of step up chopper was experimentally done.

Vo= Vin / 1-

www.eeecube.com

www.eeecube.com

36

Expt. No:

Date :

3 PHASE IGBT BASED PWM INVERTER

AIM To hook up the circuit of 3 phase IGBT based PWM inverter and observe the

output

APPARATUS REQUIRED

S.No. Name of the Apparatus Type/Range Quantity

1.

2

3

4

5

IGBT 3-Ph PWM Inverter Power Module

3-Ph Inverter firing Technology

CRO

Probe / Power card

Patch cards

LT-9043

1

1

1

As Req..

As Req..

PROCEDURE

1. Connections are given as per the circuit diagram

2. The firing circuit is connected with the carrier signal (or) the control signal is

varied

3. Output waveforms across Load are observed by CRO.

4. Now compare practical and theoretical cutout voltages.

www.eeecube.com

www.eeecube.com

37

IGBT 3-PHASE PWM INVERTER POWER MODULE :-

IGBT 3-PHASE PWM INVERTER PWM PULSE MODULE :-

www.eeecube.com

www.eeecube.com

38

WAVEFORM :-

www.eeecube.com

www.eeecube.com

39

TABULATION

S.No. Input- Vs Vo (Practical) Vo (Practical) T(ms)

1

2

3

4

Example Calculation

Theoretical output voltage –R-Phase

Step 1 Vao = vs/3 = 40/3 = 13.3 v |:

Step 2 Vao= 2vs/3 = 2x40/3 = 26.6 v

Step 3 Vao = vs/3 = 40/3 = 13.3v |:

Step 4 Vao= -vs/3 = -40/3 = -13.3 v

Step 5 Vao= -2vs/3 = - 2x40/3 = -26.6v |:

Step 6 Vao = -vs/3 = -40/3 = -3.3v

Thus the Line voltage for 3 – Phase star connected load is obtained.

Result

Thus the three phase IGBT pulse with modulation inverter output waveforms was

experimentally obtained

www.eeecube.com

www.eeecube.com

40

Expt. No:

Date :

SINGLE PHASE IGBT PWM INVERTER POWER MODULE

AIM: To construct and study the single phase PWM inverter operation with and without

filter and obtain the output

APPARATUS REQUIRED

S.No. Name of the apparatus Quantity

1.

2

3

4

5

IGBT 1-Ph PWM Inverter

Power Module

1-Ph Inverter firing Technology

CRO

Probe / Power card

Patch cards

1

1

1

As Req..

As Req..

PROCEDURE

1. Connect the circuit as per the circuit diagram

2. switch “ ON ” the main supply

3. Varying the input power signal using knob, measure the output voltage using CRO

& voltmeter and hence plot the graph.

www.eeecube.com

www.eeecube.com

41

IGBT 1-PHASE POWER MODULE :-

WAVE FORM :-

www.eeecube.com

www.eeecube.com

42

IGBT 1-PHASE DRIVER CIRCUITS :-

www.eeecube.com

www.eeecube.com

43

With FILTER ;

S.No. Vm (Volts) Time ( ms )

1

2

Without FILTER ;

S.No.

Square Wave Signal Sine Wave Signal

Vm ( v ) T ( ms ) Vm ( v ) T ( ms )

1

2

RESULT:

Thus the output waveforms for the single phase IGBT PWM Inverter with &

without filter circuit was experimentally obtained.

www.eeecube.com

www.eeecube.com

44

Expt. No:

Date :

RESONANT DC-DC CONVERTER

AIM To construct and study the PWM dc-dc resonant converter circuit operation and

observe the output waveform,

APPARATUS REQUITED

S.No. Name of the apparatus Type/Range Quantity

1.

2

3

4

5

Power Module

Triggering circuit

CRO

Probe / Power card

Patch cards

1

1

1

As Req..

As Req..

PROCEDURE

1. Connect the circuit as per the circuit diagram

2. Switch ON the main supply

3. Varying the input power signal using knob, measure the output voltage using CRO

& voltmeter and hence plot the graph.

www.eeecube.com

www.eeecube.com

45

RESONANCE DC – DC CONVERTOR POWER MODULE :-

WAVEFORM:-

www.eeecube.com

www.eeecube.com

46

RESONANCE DC – DC CONVERTER TRIGGERING CIRCUIT :-

www.eeecube.com

www.eeecube.com

47

TABULATION :-

Input Voltage ‘Vs’ = 20 volt

S.No.

Square Wave Signal Sine Wave Signal

Vm ( v ) T ( ms ) Vm ( v ) T ( ms )

1

2

3

4

RESULT

Thus the single phase dc – dc resonant converter circuit output waveforms was

experimentally obtained.

www.eeecube.com

www.eeecube.com