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SINGLE PHASE HALF CONTROLLED BRIDGE CONVERTER
Aim: To study the single phase half controlled bridge converter with R & RL Load.
Apparatus required:
S.No. Name of the equipment Range Qty01 Single phase half controlledbridge converter power circuitand firing circuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Isolation Transformer Tapping from 30V-
230V / 5A01
05 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 DC Voltmeter 0-300V 0108 DC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram
2. Connect first 30V AC supply from Isolation Transformer to circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS
switch and trigger output ON switch.
5. Connect CRO probes and observe waveforms in CRO, Ch-1 or Ch-2, across load and
device in single phase half controlled bridge converter.
6. By varying firing angle gradually up to 1800 and observe related waveforms
7. Measure output voltage and current by connecting AC voltmeter & Ammeter
8. Tabulate all readings for various firing angles.
9. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
10. Observe the various waveforms at different points in circuit by varying the Resistive
Load and Inductive Load.
11. Calculate the output voltage and current by theoretically and compare with it
practically obtained values.
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TABULAR COLUMN:
S.No. Input Voltage(V in)
Firingangle inDegrees
Output voltage (V0) Output Current (I0)
Theoretical Practical Theoretical Practical
MODULE CALCULATIONS:
V0 = (2V / ) * (1+Cos)
I0 = (2V / R) * (1+Cos )
= Firing AngleV = RMS Value across transformer output
MODEL GRAPH:
RESULT:
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SINGLE PHASE FULLY CONTROLLED BRIDGE CONVERTER
Aim: To study the single phase fully controlled bridge converter with R & RL Load.
Apparatus required:
S.No. Name of the equipment Range Qty01 Single phase full controlled bridge
converter power circuit and firingcircuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Isolation Transformer Tapping from 30V to
230V / 5A01
05 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 DC Voltmeter 0-300V 01
08 DC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram
2. Connect firstly 30V AC supply from Isolation Transformer to circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS switch
and trigger output ON switch.
5. Connect CRO probes and observe waveforms in CRO, Ch-1 or Ch-2, across load and
device in single phase half controlled bridge converter.
6. By varying firing angle gradually up to 1800 and observe related waveforms
7. Measure output voltage and current by connecting AC voltmeter & Ammeter
8. Tabulate all readings for various firing angles.
9. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
10.Observe the various waveforms at different points in circuit by varying the Resistive Load
and Inductive Load.
11.Calculate the output voltage and current by theoretically and compare with it practically
obtained values.
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TABULAR COLUMN:
S.No. Input Voltage(V in)
Firingangle in
Degrees
Output voltage (V0) Output Current (I0)
Theoretical Practical Theoretical Practical
MODULE CALCULATIONS:
For R-L Load: For R Load:
V0 = (22V/) * Cos V0 = (2V/) * (1+Cos)
I0 = (22V/R) * Cos I0 = (2V /R) * (1+Cos)
= Firing Angle
V = RMS Value across transformer output
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MODEL GRAPH:
Fig: out put wave forms for < 900
RESULT:
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DC JONES CHOPPER
AIM: To study the related output wave forms of DC JONES CHOPPER with R & RL loads.
Apparatus required:
S.No. Name of the equipment Range Qty01 DC JONES CHOPPER power circuit
and firing circuit- 01
02 C.R.O. with deferential module - 0103 Patch chords and C.R.O. probes - Adequate04 Regulated dc power supply 30V/5A 0105 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 DC Voltmeter 0-100V 0108 DC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram
2. Give the DC power supply 10V to the terminal pins located in the power circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS switch
and trigger output ON switch.
5. By varying the frequency and duty cycle, observe related waveforms
6. Measure output voltage and current by connecting DC voltmeter & Ammeter
7. Observe waveforms and readings, changing the frequency and duty cycle, and Tabulate
all readings
8. Calculate the output voltage and current by theoretically and compare with it practically
obtained values.
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TABULAR COLUMN:
S.NO VIN TON TOFF
DUTY CYCLE
= TON/ T VO IO
MODULE CALCULATIONS:
VO = * VIN
IO = VO / R
MODEL GRAPH:
RESULT:
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SERIES INVERTER
AIM: To study the series inverter.
Apparatus required:
S.No. Name of the equipment Range Qty01 Series inverterpower circuit and firingcircuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Regulated dc power supply 30V/5A 0105 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram
2. Give the DC power supply 30V to the terminal pins located in the power circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS switch
and trigger output ON switch.
5. By varying the frequency pot, observe related waveforms
6. If the inverter frequency is increases above the resonant frequency of the power circuit
commutation fails. Then switch OFF the DC supply , reduce the inverter frequency and try
again.
7. Repeat the above same procedure for different value of L,C load and also above the wave
forms with and without fly wheel diodes.
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8. Total out put wave forms entirely depends on the load, and after getting the perfect
wave forms increase the input supply voltage up to 30V and follow the above procedure.
9. Switch OFF the DC supply first and then Switch OFF the inverter.( Switch OFF the trigger
pulses will lead to short circuit)
fo = 1/21/LC-(R/L)2
MODEL GRAPH:
RESULT:
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THREE PHASE HALF CONTROLLED BRIDGE CONVERTER
Aim: To study the three phase half controlled bridge converter with R & RL Load.
Apparatus required:
S.No. Name of the equipment Range Qty01 Three phase half controlled
bridge converter power circuitand firing circuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Isolation Transformer 415V / 5A
(with tapings)01
05 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 DC Voltmeter 0-300V 0108 DC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram
2. Connect firstly 30V AC supply from Isolation Transformer to circuit
3. Connect resistive load 200 / 5A to load terminals and switch ON the MCB
4. Observe waveforms in CRO, across load and device in three phase half controlled
bridge converter.
5. By varying firing angle gradually up to 1800 and observe related waveforms
6. Measure output voltage and current by connecting DC voltmeter & Ammeter
7. Now increase the input supply voltage by changing tapping at Isolation Transformer.
Observe waveforms and readings, changing the supply voltage up to 230V. Tabulate
all readings at various angles and various voltages.
8. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
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9. Observe the various waveforms at deferent points in circuit by varying the Resistive
Load and Inductive Load.
10. Calculate the output voltage and current by theoretically and compare with it
practically obtained values.
TABULAR COLUMN:
S.No. Input Voltage(V in)
Firingangle inDegrees
Output voltage (V0) Output Current (I0)
Theoretical Practical Theoretical Practical
MODULE CALCULATIONS:
V0 = (32V /2) * (1+Cos)
I0 = (32V /2R) * (1+Cos )
= Firing AngleV = RMS Value across transformer output
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MODEL GRAPH:
RESULT:
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SINGLE PHASE A.C. VOLTAGE CONTROLLER
Aim: To study the single phase AC voltage controller with R & RL Load.
Apparatus required:
S.No. Name of the equipment Range Qty01 Single phase AC voltage
controller power circuit and firingcircuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Isolation Transformer 230V / 5A 0105 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 AC Voltmeter 0-300V 0108 AC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
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PROCEDURE:
AC voltage controller with two thyristors:
1. Make all connections as per the circuit diagram
2. Connect firstly 30V AC supply from Isolation Transformer to circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS
switch and trigger output ON switch.
5. Observe waveforms in CRO, across load by varying firing angle gradually up to 1800.
6. Measure output voltage and current by connecting AC voltmeter & Ammeter
7. Tabulate all readings for various firing angles.
8. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
9. Observe the various waveforms at different points in circuit by varying the Resistive
Load and Inductive Load.
10. Calculate the output voltage and current by theoretically and compare with itpractically obtained values.
A.C. voltage controller with TRIAC:
1. Make all connections as per the circuit diagram
2. Connect firstly 30V AC supply from Isolation Transformer to circuit
3. Connect firing pulse from firing circuit to TRIAC as indication in circuit4. Connect resistive load 200 / 5A to load terminals and switch ON the MCB and IRS
switch and trigger output ON switch.
5. Observe waveforms in CRO, across load by varying firing angle gradually up to 1800.
6. Measure output voltage and current by connecting AC voltmeter & Ammeter
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7. Tabulate all readings for various firing angles.
8. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
9. Observe the various waveforms at different points in circuit by varying the Resistive
Load and Inductive Load.
10. Calculate the output voltage and current by theoretically and compare with itpractically obtained values.
TABULAR COLUMN:
S.No. Input Voltage(V in)
Firingangle inDegrees
Output voltage (V0r) Output Current (I0r)
Theoretical Practical Theoretical Practical
MODULE CALCULATIONS:
V0r = (V / ) * [(-) +{(sin2)/2} ]I0r = V0r/R
= Firing Angle
V = RMS Value across transformer output
MODEL GRAPHS:
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Fig: Voltage controller with R-load
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RESULT:
SINGLE PHASE CYCLOCONVERTER
AIM: To study the single phase Cyclo converter with R & RL Load.
Apparatus required:
S.No. Name of the equipment Range Qty01 Single phase Cyclo converterpower circuit and firing circuit
- 01
02 CRO with deferential module - 0103 Patch chords and probes - Adequate04 Isolation Transformer (centre-
tapped )230V-0-230V / 5A(with tappings)
01
05 Variable Rheostat 0-200 / 5A 0106 Inductor 0-50-150 mH / 5A 0107 AC Voltmeter 0-300V 0108 AC Ammeter 0-5A 01
CIRCUIT DIAGRAM:
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PROCEDURE:
1. Make all connections as per the circuit diagram
2. Connect firstly (30V-0-30V) AC supply from Isolation Transformer to circuit
3. Connect firing pulses from firing circuit to Thyristors as indication in circuit
4. Connect resistive load 200 / 5A to load terminals.
5. Set the frequency division switch to (2,3,4,9) your required output frequency.
6. Switch ON the MCB and IRS switch and trigger output ON switch.
7. Observe waveforms in CRO, across load by varying firing angle gradually up to 1800
and also for various frequency divisions(2,3,4,9).
8. Measure output voltage and current by connecting AC voltmeter & Ammeter
9. Tabulate all readings for various firing angles.
10. For RL Load connect a large inductance load in series with Resistance and observe all
waveforms and readings as same as above.
11. Observe the various waveforms at different points in circuit by varying the Resistive
Load and Inductive Load.
12. Calculate the output voltage and current by theoretically and compare with it
practically obtained values.
TABULAR COLUMN:
Sl.No
InputVoltage
(V in)
Firingangle inDegrees
FrequencyDivision
V o
(V)
I o
(A)
Inputfrequency
fs
Outputfrequency
fo
fo / fs
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MODULE CALCULATIONS:
V0r = (V / ) * [(-) +{(sin2)/2} ]I0r = V0r/R
= Firing Angle
V = RMS Value across transformer output
MODEL GRAPH:
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RESULT:
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STUDY OF SCR CHARACTERISTICS
AIM: To study the V-I Characteristics of SCR. Finding the value of Latching current, Holding
current, Gate voltage and gate current.
Apparatus required:
S.No. Name of the equipment Range Qty01 SCR characteristics Trainer - 01
02 Patch chords - Adequate03 DC Voltmeter 0V-20V
0V-50V0101
04 DC Ammeter 0-25mA0-500mA
0101
CIRCUIT DIAGRAM:
PROCEDURE:
V-I CHARACTERISTICS:-
1. Make all connections as per the circuit diagram.
2. Initially keep V1 & V2 at minimum position and R1 & R2 maximum position.
3. Adjust Gate current Ig to some constant(2.5/5.0mA) by varying the V1 or R1.
4. Now slowly vary V2 and observe Anode to Cathode voltage VAK and Anode current IA.
5. Tabulate the readings of Anode to Cathode voltage VAK and Anode current IA.
6. Repeat the above procedure for different Gate current Ig.
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GATE TRIGGRING AND FINDING VG AND IG:-
1. Keep all positions at minimum.
2. Set Anode to Cathode voltage VAK to some volts say 15V.
3. Now slowly vary the V1 voltage till the SCR triggers and note down the reading of gate
current(IG) and Gate Cathode voltage(VGK) and rise of anode current IA
4. Repeat the same for different Anode to Cathode voltage and find VAK and IG values.
TO FIND LATCHING CURRENT:-
1. Keep R2 at middle position.
2. Apply 20V to the Anode to cathode by varying V2
3. Rise the Vg voltage by varying V1 till the device turns ON indicated by sudden rise in IA .
At what current SCR trigger it is the minimum gate current required to turn ON the SCR.
4. Now set R2 at maximum position, then SCR turns OFF, if it is not turned off reduce V2 up
to turn off the device and put the gate voltage.
5. Now decrease the R2 slowly, to increase the Anode current gradually in steps.
6. At each and every step, put OFF and ON the gate voltage switches V1. If the Anode
current is greater than the latching current of the device, the device says ON even after
switch OFF S1, otherwise device goes to blocking mode as soon as the gate switch is put
OFF.
7. If IA>IL then, the device remains in ON state and note that anode current as latching
current.
8. Take small steps to get accurate latching current value.
TO FIND HOLDING CURRENT:-
1. Now increase load current from latching current level by varying R2 & V2
2. Switch OFF the gate voltage switch S1 permanently (now the device is in ON state)
3. Now increase load resistance(R2), so that anode current reducing, at some anode current
the device goes to turn off .Note that anode current as holding current.
4. Take small steps to get accurate holding current value.
5. Observe that IH
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VAK = (Volts)VGK = V IG= A
MODEL GRAPH:
RESULT:
IG= AVAK (Volts) IA (Amps)
VAK = (Volts)VGK = V IG= A
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STUDY OF MOSFET CHARACTERISTICS
AIM: To study the Output and Transfer Characteristics of MOSFET.
Apparatus required:
S.No. Name of the equipment Range Qty01 MOSFET characteristics Trainer - 01
02 Patch chords - Adequate03 DC Voltmeter 0V-20V
0V-50V0101
04 DC Ammeter 0-500mA 01
CIRCUIT DIAGRAM:
PROCEDURE:
TRANSFER CHARACTERISTICS:
1. Make all connections as per the circuit diagram.
2. Initially keep V1 & V2 at minimum position and R1 & R2 middle position.
3. Set VDS to some say 10V.
4. Slowly vary Gate source voltage VGS by varying V1.
5. Note down ID and VGS readings for each step.
6. Repeat above procedure for 20V & 30V of VDS. Draw Graph between ID & VGS.
OUTPUT CHARACTERISTICS:
1. Initially set VGS to some value say 3V by varying V1.
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2. Slowly vary V2 and note down ID and VDS
3. At particular value of VGS there a pinch off voltage between drain and source.
If VDS< VP device works in the constant resistance region and IO is directly proportional
to VDS. If VDS>VP device works in the constant current region.
4. Repeat above procedure for different values of VGS and draw graph between IDVSVDS.
TABULAR COLUMN:
VGS = V
VDS (Volts) ID (Amps)
VDS= (Volts)
VGS (V) ID(A)
MODEL GRAPH:
Fig: Transfer Characteristics fig: Output Characteristics
VGS = VVDS (Volts) ID (Amps)
VDS = (Volts)
VGS (V) ID(A)
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RESULT:
STUDY OF IGBT CHARACTERISTICS
AIM: To study the Output and Transfer Characteristics of IGBT.Apparatus required:
S.No. Name of the equipment Range Qty01 IGBT characteristics Trainer - 01
02 Patch chords - Adequate03 DC Voltmeter 0V-20V
0V-50V0101
04 DC Ammeter 0-500mA 01
CIRCUIT DIAGRAM:
PROCEDURE:
TRANSFER CHARACTERISTICS:
1. Make all connections as per the circuit diagram.
2. Initially keep V1 & V2 at minimum position and R1 & R2 middle position.
3. Set VCE to some say 10V.
4. Slowly vary Gate Emitter voltage VGE by varying V1.
5. Note down IC and VGE readings for each step.
6. Repeat above procedure for 20V & 25V of VDS. Draw Graph between ID & VGS.
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OUTPUT CHARACTERISTICS:
1. Initially set VGE to some value say 5V by varying V1.
2. Slowly vary V2 and note down IC and VCE readings.
3. At particular value of VGS there a pinch off voltage VP between Collector and Emitter.
If VCE< VP device works in the constant resistance region and IC is directly proportionalto VCE. If VCE>VP device works in the constant current region.
4. Repeat above procedure for different values of VGE and draw graph between ICVSVGE.
TABULAR COLUMN:
VCE = VVGE (Volts) IC (Amps)
VGE= (Volts)VCE (V) IC(A)
MODEL GRAPH:
Fig: Transfer Characteristics fig: Output Characteristics
VCE =VVGE (Volts) IC (Amps)
VGE = (Volts)VCE (V) IC(A)
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RESULT:
R-C TRIGGERING
AIM:To study the Resistance-capacitance (RC) Triggering circuit of SCR.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty
01 Resistance-Capacitance Firing Circuit - 01
02 Patch chords - Adequate03 CRO with differential module - 01
04 R-Load 0-200/2A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram.
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2. Give the AC Power supply 20V/1A from the source indicated in the front panel.
3. Connect Load i.e., Rheostat of 200 between two points.
4. Switch ON Power supply and observe the wave forms of Input & Output at a time
in the CRO.CH-1&CH-2
5. Slowly vary the control Resistor RC, that Firing angle can vary from 0-180.
6. Observe various voltage waveforms across load, SCR and other points, by varying theLoad Resistance and Firing RC part.
7. Compare practical obtained voltage waveform with theoretical waveform and observe the
Firing angle in R-C Triggering.
Model graph:
RESULT:
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RESISTANCE TRIGGERING
AIM:To study the Resistance Triggering circuit of SCR.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty
01 Resistance Firing Circuit - 01
02 Patch chords - Adequate03 CRO with differential module - 01
04 R-Load 0-200/2A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Make all connections as per the circuit diagram.
2. Give the AC Power supply 20V/1A from the source indicated in the front panel.
3. Connect Load i.e., Rheostat of 200 between two points.
4. Switch ON Power supply and observe the wave forms of Input & Output at a time
in the CRO.CH-1&CH-2
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UJT TRIGGERING
AIM: To study Firing of SCR using UJT Relaxation Oscillator and also to study UJT RelaxationOscillator in unsynchronized mode
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty
01 UJT FIRING CIRCUIT - 01
02 Patch chords & Probes - Adequate
03 CRO with differential module - 0104 R-Load 0-200/2A 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. First observe the waveforms at different points in circuit and also trigger output T1 and
T1` observe the pulses are synchronized.
2. Now make the connections as per circuit using AC source, UJT Relaxation Oscillator,
SCRs and Loads.
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3. Observe the waveforms across the load and SCR and other points, by varying the variable
resistor Rc and resistance load, observe firing angle of SCR.
4. Use differential module for observing two waveforms (input and output) simultaneously in
channel 1 and channel 2.
5. Check the waveforms for large value of RC and small value of RC and also triggering
points of SCR.FOR RELAXATION OSCILLATOR:
1. Short the CF capacitor to the diode bridge rectifier to get filtered AC Output.
2. We get equidistance pulses at the output of pulse transformer.
3. The frequency of pulse can be varied by varying the potentiometer.
4. Observe that capacitor charging and discharging time periods and calculate frequency
and RC time constant of UJT Relaxation Oscillator by using given formulas.
MODEL GRAPH:
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RESULT:
SPEED CONTROL OF THREE PHASE WOUND INDUCTION MOTOR
AIM: To control the speed of three phase wound rotor induction motor.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty
01 Chopper module - 01
02 Patch chords & Probes - Adequate03 CRO - 01
04 R-Load 0-50/2A 01
05 3 phase auto transformer 415V/10A 01
06 3 phase wound rotor induction motor -- 01
CIRCUIT DIAGRAM:
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PROCEDURE:
1. Make Power circuit connections as shown in the circuit diagram.
2. Give 3 phase supply to the wound rotor induction motor, through 3 phase auto
transformer.
3. Now, the rotor terminals(R,Y,B) of induction motor is connected to the respective
terminals(R,Y,B) of motor control unit.
4. Connect the load rheostat (50 ohm) across load terminals and also CRO probe.
5. Keeping duty cycle knob at minimum position switch on the chopper firing circuit.
6. Keeping auto transformer at minimum position switch on the 3 phase mains. Switch on
the chopper power circuit using 3 phase MCB.
7. Increase the auto transformer voltage slowly(up to 30% of auto T/F output ) for suitable
value such that motor rotates
8. Vary duty cycle of the chopper firing circuit in steps and note down corresponding rpm.
9. Plot a graph of duty cycle against speed.
TABULAR COLUMN:
Sl.No Duty cycle
In %
Speed in RPM
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MODEL GRAPH:
RESULT:
CLOSED LOOP SPEED CONTROL OF 1HP DC MOTOR
AIM: To control the speed of the DC motor using thyristorised converter unit.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty
01 Thyristorised drive for DC motor. - 01
02 Patch chords & Probes - Adequate03 CRO - 01
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04 Isolation transformer(With tappings) - 01
05 1hp DC motor -- 01
CIRCUIT DIAGRAM:
PROCEDURE:
1. Connect DC motor field & armature terminals to respective points in the power circuit and
speed sensor to feedback terminals socket. Connect the volt meter & ammeter to the
respective points.
2. Circuit connections are made as shown in the circuit diagram.
3. Check the connections and conform the connections made are correct before switching on
mains supply.
4. Keeping all the knobs at minimum position.
5. Keeping PID controllers switches ON (down ward) position.6. Switch ON the field supply to the motor.
7. Switch ON the firing controller power supply switch.
8. Set the rpm to suitable value (say 800 rpm) and switch ON the power circuit.
9. Using P,I,D knobs adjust the running rpm to set rpm by varying P gain, I timing , D gain.
10. Load the motor up to 3-4A (in steps of 1A)and note down the speed for each
step.Observe the current & voltage wave forms using CRO.
11.Slowly reduce the load, set rpm to minimum value, Switch off MCB. Switch off the
triggering circuit, Switch off field supply & remove the connections.
TABULAR COLUMN:
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Set RPM=800 rpm Set RPM=1000 rpm
MODEL GRAPH:
Sl.No Load
current
Running RPM
Sl.No Load
current
Running RPM
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RESULT:
SINGLE PHASE DUAL CONVERTERAIM: To study the dual converter with R & L load.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty01 Single phase dual converter.(power
circuit & firing circuit.)- 01
02 Patch chords & Probes - Adequate03 CRO - 01
04 Isolation transformer(With tappings) - 0105 R load 0-200 ohm / 5A 0106 L load(center tapped) 300-0-300mH/5A 01
CIRCUIT DIAGRAM:
NON- CIRCULATING CURRENT MODE:
CIRCULATING CURRENT MODE:
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PROCEDURE:
NON- CIRCULATING CURRENT MODE:
1. Make all connections as per the non circulatory circuit diagram.
2. Connect R-load across load terminals.
3. Connect the input AC supply to the power circuit through an Isolating Transformer(take
input voltage 30V)
4. Select the NCC mode in firing circuit.
5. Give the firing pulses and keep P-converter in ON position and also put on the MCB
switch.
6. By varying the firing angle observe related out put waveforms in the CRO.Tabulate all the
readings.
7. Repeat all above procedure for RL-load.
CIRCULATING CURRENT MODE:
1. Make all connections as per the circulatory circuit diagram.
2. Connect R-load across load terminals.
3. Connect the input AC supply to the power circuit through an Isolating Transformer(take
input voltage 30V)
4. Select the CC mode in firing circuit.
5. Give the firing pulses and keep P-converter in ON position and also put on the MCB
switch.
6. By varying the firing angle observe related out put waveforms in the CRO.Tabulate all the
readings.
7. Repeat all above procedure for RL-load.
TABULAR COLUMN:
S.No. Input Voltage(V in)
Firingangle inDegrees
Output voltage (V0) Output Current (I0)
Theoretical Practical Theoretical Practical
MODULE CALCULATIONS:
V0 = (22V / ) * (Cos1)
I0 = (22V / Z) * (Cos1)
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= Firing Angle
V = RMS Value across transformer output
MODEL GRAPH:
RESULT: The single phase dual converter with R & RL load is studied.
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PARALLEL INVERTER
AIM: To study the parallel inverter.
APPARATUS REQUIRED:
S.No. Name of the equipment Range Qty01 Parallel inverter circuit. - 01
02 Patch chords & Probes - Adequate03 CRO - 0104 Regulated power supply 30V/5A 0105 R load 0-200 ohm / 5A 01
CIRCUIT DIAGRAM:
PRCEDURE:
1. Make all connections as per the circuit, and give regulated power supply 30V/5A.
2. Give trigger pulses from firing circuit to gate and cathode of SCRs T1 & T2.
3. Set input voltage 15V, connect load across load terminals.
4. Now switch ON the DC supply, switch ON the trigger output pulses.
5. Observe the output voltage waveforms across load by varying the frequency pot.
6. Repeat the above same procedure for different value of L,C load values.
7. Switch off the DC supply first and then switch off the inverter.
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(switch off the trigger pulses will lead to short circuit)
MODEL GRAPH:
RESULT: