ELECTRICAL CIRCUITS LAB MANUAL · 4) maximum power transfer theorem 5) verification of superposition theorem and reciprocity theorem 6) impedance and admitance parameters 7) transmission

ELECTRICAL CIRCUITS LAB

Electrical and Electronics Engineering ANURAG COLLEGE OF ENGINEERING

1


MANUAL



2


APPENDIX

1) SELF INDUCTANCE, MUTUAL INDUCTANCE AND COEFFICIENT

OF COUPLING OF A SINGLE PHASE TRANSFORMER

2) RESONANCE IN SERIES RLC CIRCUIT

3) RESONANCE IN PARALLEL RLC CIRCUIT

4) MAXIMUM POWER TRANSFER THEOREM

5) VERIFICATION OF SUPERPOSITION THEOREM AND

RECIPROCITY THEOREM

6) IMPEDANCE AND ADMITANCE PARAMETERS

7) TRANSMISSION AND HYBRID PARAMETERS

8) THEVENIN’S AND NORTON’S THEOREMS

9) LOCUS DIAGRAM

10) COMPENSATION THEOREM



3

EXPERIMENT-1

SELF INDUCTANCE, MUTUAL INDUCTANCE AND COEFFICIENT OF

COUPLING OF A SINGLE PHASE TRANSFORMER

AIM: To determine the self inductance, mutual inductance and coefficient of coupling of

a single phase transformer.

NAME PLATE DETAILS: 1) Rated Voltage:

2) Rated KVA

3) Rated Frequency:

APPARATUS REQUIRED: 1)1-Ø Variac -

2) Voltmeters -

3) Ammeters-

CIRCUIT DIAGRAMS:



4

PROCEEDURE: CIRCUIT-1

1. Connect the circuit as shown in the circuit diagram.

2. Keep the varaic output voltage in the minimum position.

3. Switch on the supply.

4. Vary the variac till rated voltage is obtained on the HV side.

5. Note down the readings of all meters.

CIRCUIT-2

1. Connect the circuit as shown in the circuit diagram.

2. Keep the varaic output voltage in the minimum position.

3. Switch on the supply.

4. Vary the variac till Rated is obtained on the LV side.

5. Note down the readings of all meters.

CALCULATIONS:

CIRCUIT-1

Input impedance,Z1 = R1+jωL1= 1

1

I

V

Neglecting resistance, ωL1=

1

1

I

V

Self inductance of HV coil L1=1

1

I

V

Mutual inductance M12= 1

2

I

V

CIRCUIT-2

Input impedance,Z2 = R2+jωL2= 2

2

I

V

Neglecting resistance, ωL2=

2

2

I

V

Self inductance of LV coil L2=2

2

I

V

Mutual inductance M21= 2

1

I

V

M=2

2112 MM

Coefficient of coupling K= 21LL

M



5

TABULAR COLUMN:

CIRCUIT I1(A) V1(V) V2(V) SELF

INDUCTANCE(L)

MUTUAL

INDUCTANCE (M)

CIRCUIT-1

CIRCUIT-2

RESULT: Self inductance of HV coil L1=

Self inductance of LV coil L2=

Mutual inductance M12=

Mutual inductance M21=

Coefficient of coupling K=

PRECAUTIONS: 1) Check all the rheostats before making connections.

2) Connections should be made properly

3) Always kept the varaic output voltage in minimum position before

and after switch on the supply.

4) Show connections to the lab faculty before you start the experiment

5) Note down the readings with out parallax error

VIVA-VOCE: 1) Define self, mutual inductance & coefficient of coupling?

2) Why K value less than one?

3) What happen when resistance of winding also consider?



6

EXPERIMENT-2

RESONANCE IN SERIES RLC CIRCUIT

AIM: To find different characteristics of a series RLC circuit at resonance condition

APPARATUS: 1) Ammeter –

2) Decade resistance box.

3) Decade Inductance box.

4) Decade Capacitance box.

5) Function generator.(FG)

CIRCUIT DIAGRAM:

THEORY: An AC circuit is said to be in resonance when applied voltage and resultant

current are in phase. Resonance in series circuit is referred to as series resonance. Thus at

resonance, power factor will be unity, the net reactance will be zero and the equivalent

complex impedance of the circuit consists of only the resistance.

Since inductance and capacitance are essentially energy storing devices, it is

convenient to discuss their efficiency to store energy which is called Quality factor. The

quality factor determines the selectivity of the resonant circuit. As the resistance

decreases the quality factor increases and band width decreases. The current will be

maximum at resonace.Below the resonance, capacitive reactance is more and above

resonance inductive reactance is more. On the impedance versus frequency curve at half

power frequencies, the resistance and reactance are equal.

PROCEDURE: 1) Connect the circuit as per the circuit diagram

2) Fix the input voltage to 6V p-p

3) By varying the frequency of the function generator ,note the

readings of Ammeter.



7

THEORETICAL CALCULATIONS:

The given RLC series connected element values are

R=1K Ohm, L=20mH, C=50nF

1

Resonant Frequency (fr)=_________ =

2П√ (LC)

Lower cut-off Frequency (f1)= fr - R / (4 П L)

Upper cut-off Frequency (f2)= fr + R / (4 П L)

Band-width = f2 - f1

Quality Factor (Q) = fr / ( f2 - f1)

TABULAR COLUMN : Voltage = 6 Vpp (Maintained constant)

EXPECTED GRAPHS:

S.NO

FREQUENCY

I(mA)

XL = ωL

(Ohm)

XC =1/ ωC

(Ohm)

Z=√(R2 +( XL - XC)2)

(Ohm)



8

RESULT:

S.NO QUANTITY THEORETICAL

VALUES

PRACTICAL

VALUES

PRECAUTIONS: 1) Check all the apparatus before making connections

2) Connections should be made properly.

3) Show connections to the lab faculty before you start the

experiment.

4) Note down the readings with out parallax error.

VIVA-VOCE: 1) Define resonance?

2) Define resonant frequency, half power frequencies, Band width-

Q-factor, selectivity?

3) How the circuit behaves before and after resonant frequency?

4) Explain the expected graphs?



9

EXPERIMENT-3

RESONANCE IN PARALLEL RLC CIRCUIT

AIM: To find different characteristics of a parallel RLC circuit at resonance.

APPARATUS: 1) Ammeter –.

2) Decade resistance box.

3) Decade Inductance box.

4) Decade Capacitance box.

5) Function generator.

CIRCUIT DIAGRAM:

THEORY:

An AC circuit is said to be in resonance when applied voltage and resultant

current are in phase. Resonance in parallel circuit is referred to as parallel resonance.

Thus at resonance, power factor will be unity, the net susceptance will be zero and the

equivalent complex admittance of the circuit consists of only the conductance.

Since inductance and capacitance are essentially energy storing devices, it is

convenient to discuss their efficiency to store energy which is called Quality factor. The

quality factor determines the selectivity of the resonant circuit and is defined as the band

of frequencies which lies between two points on either side of resonant frequency where

impedance falls to 1/√2 times of its value at resonance. At these frequencies, the

conductance and susceptance are equal.

PROCEDURE: 1) Connect the circuit as per the circuit diagram

2) Fix the input voltage to 6V p-p

3) By varying the frequency of function generator, note the

readings of Ammeter



10


The given RLC Parallel connected element values are

R=1 Ohm, L=20mH, C=50nF

1

Resonant Frequency (fr)=_________ = 5.032 KHz

2П√ (LC)

Lower cut-off Frequency (f1)= fr - 1/2П[-1/2RC+√(1/2RC)2+1/LC]

Upper cut-off Frequency (f2)= fr + 1/2П[1/2RC+√(1/2RC)2+1/LC]

Band-width = f2 - f1

Quality Factor (Q) = fr / ( f2 - f1)

TABULAR COLUMN: Voltage-6Vpp ( Maintained constant)

S.NO

FREQUENCY

I(mA)

XL = ωL

(Ohm)

XC =1/ ωC (Ohm)

Y=√ (1/R)2+(1/XL-1/Xc)2

(Ohm)

Z=1/Y

EXPECTED GRAPHS:



11

RESULT:

S.NO QUANTITY THEORETICAL

VALUES

PRACTICAL

VALUES

PRECAUTIONS: 1) Check all the apparatus before making connections.




VIVA-VOCE: 1) Define resonance?

2) Define resonant frequency, half power frequencies, Band width-

Q-factor, selectivity?

3) How the circuit behaves before and after resonant frequency?

4) Explain the expected graphs?



12

EXPERIMENT-4

MAXIMUM POWER TRANSFER THEOREM

AIM: To verify the maximum power transfer theorem for DC Circuits

APPARATUS 1) Resistors

2) Regulated power supply

3) Voltmeter

4) Ammeter

5) Decade resistance box

6) Connecting wires.

7) Bread board.

CIRCUIT DIAGRAM:

THEORY:

The maximum power is delivered to the load when load resistance is equal to the

source resistance.

APPLICATION: Radio speaker system or a micro phone supplying the input signals to

voltage pre-amplifiers.

PROCEDURE:

1) Connections are made as per the circuit diagram.

2) Fix the input supply voltage to 4v.

3) Then vary the load resistance and note down the corresponding Ammeter & Voltmeter

readings.

4) Calculate the power for each set of values.



13

THEORETICAL CALCULATIONS

Step: 1To find Rth :

Short circuit voltage source & open circuit load resistance.

Rth == 21

133221

RR

RRRRRR

=

Step: 2 To find Vth :

open circuit load resistance only.

Z = R1 + R2 =

I =

Z

V1=

Vth =I x R2 = 21

1

RR

V

x R2

Step: 3 To find IL :

IL = Lth

th

RR

V

Maximum power transferred to the load = {IL2at Lth RR } x Rth =

th

th

R

V

4

2

.

TABULAR COLUMN:

S.NO RL(KΩ) VL(V) IL(mAmp) P=VLIL(W)

EXPECTED GRAPH:



14

RESULT:

Maximum power is transferred to the load i.e.P=______ when load resistance is equal to

the source resistance



3) Show connections to the lab faculty before you start the

Experiment


VIVA-VOCE:1)State maximum power transfer theorem?

2) What is the condition for maximum current transfer to the load?

3) What is the application of maximum power transfer theorem?

4) What is the efficiency of power transfer when maximum power transfer

to the load?



15

EXPERIMENT-5

VERIFICATION OF SUPERPOSITION THEOREM AND

RECIPROCITY THEOREM

AIM: To verify the superposition theorem and Reciprocity theorem.

APPARATUS:1)Rheostats-

2) Ammeter

3) Voltmeter

4) Potential divider

5) Connecting wires

CIRCUIT DIAGRAM:

Superposition theorem

TO FIND TOTAL CURRENT:

CKT-1

TO FIND CURRENT IN R2 WHEN V1 IS ACTING ALONE:

CKT-2



16

TO FIND CURRENT IN R2 WHEN V2 IS ACTING ALONE

CKT- 3

Reciprocity theorem

WHEN V1 ACTING ALONE:

CKT-1

WHEN V2 ACTING ALONE:

CKT-2



17

THEORY:

Superposition theorem:

Superposition theorem states that in any linear network containing two or

more sources, the response in any element is equal to the algebraic sum of the responses

caused by individual sources acting alone, while the other sources are non operative that

is while considering the effect of individual sources, other ideal voltage sources and ideal

current sources in the network are replaced by short circuits and open circuits

respectively.

Reciprocity theorem:

This theorem states that in any linear bilateral network the ratio of a

voltage V introduced in one mesh to the current in any other mesh is the same ratio

obtained if the positions of V and I are interchanged, other emf being removed.

PROCEDURE:


1) Connect the circuit as per circuit diagram.(1)

2) Apply both the voltages V1and V2 and not down the value read the current I in the

Ammeter, through resistor R2

3) Connect the circuit as per circuit diagram.(2) by making one voltage source short

circuited, record the current I1 through resistance R2

4) Connect the circuit as per circuit diagram.(3) by short circuiting the other voltage

source and ,record the current I2 through the resistance R2

5) Now observe that I=I1+I2



2) Note down the voltage V1 and the corresponding current I2

3) Now interchange the voltage source and Ammeter as shown in figure (2)

4) Note down the voltage V2and the corresponding current I1 5) Observe that V1 /I2=V2/I1


Superposition theorem

1) When V1 acting alone:

Z1 ==

32

133221

RR

RRRRRR

=

I=

1

1

Z

V=

I1 in (R2)=I x32

3

RR

R

= V1 x

133221

3

RRRRRR

R

=



18

2) When V2 acting alone:

Z ==21

133221

RR

RRRRRR

=

I = Z

V 2=

I2 in (R2)=I x 21

1

RR

R

= V2 x

133221

1

RRRRRR

R

=

I1 + I2 =133221

3112

RRRRRR

RVRV

=

Hence I = I1 + I2


When V1 source acting:

Z1 = 32

313221

RR

RRRRRR

=

I1=

1

1

Z

V=

I2=I1 x 32

2

RR

R

=

I2=V1 x313221

2

RRRRRR

R

=

2

1

I

V=

2

313221

R

RRRRRR =

When V2 source acting:

Z2 = 32

313221

RR

RRRRRR

=

I2=

2

2

Z

V=

I1=I2 x 21

2

RR

R

=

I1=V2 x313221

2

RRRRRR

R

=



19

1

2

I

V=

2

313221

R

RRRRRR =

Hence 2

1

I

V=

1

2

I

V

TABULAR COLUMN:


S.NO V1(V) V2 (V) I(mA) I1(mA) I 2(mA) I=I1+I2


S.NO V1(V) V2 (V) I1(mA) I 2(mA) V1/I2

V2/I1

V1 /I2=V2/I1

RESULT:

1) Superposition theorem is verified for many applied voltages as shown in the table i.e

I=I1+I2

2) Reciprocity theorem is verified for many applied voltages as shown in the table i.e V1 /I2=V2/I1


2) Connections should be made properly.

3) Always kept the potential divider output voltage in minimum

Position before and after switch on the supply.



VIVA-VOCE:1)State super position theorem?

2) State reciprocity theorem?

3) What are the applications super position theorem?

4) What are the applications of reciprocity theorem?

5) What are the limitations of super position & reciprocity theorem?



20

EXPERIMENT-6

IMPEDANCE AND ADMITANCE PARAMETERS

AIM: To determine Impedance & Admittance parameters for a given two port network.

APPARATUS:1)Rheostats-

2) Voltmeter

3) Ammeter

4) Potential divider-

5) Connecting wires

CIRCUIT DIAGRAM:

Z-parameters:

To find Z11 & Z21:

CKT-1

To find Z12 & Z22:

CKT-2



21

Y-parameters

To find Y11 & Y21:

CKT-1

To find Y12 & Y22:

CKT-2

THEORY:

In Z-parameters the port voltages are expressed in terms of port currents and

Z-parameters. The network is said to be symmetrical network when Z11=Z22 .The network

is said to be reciprocal network, when Z12=Z21. Z12 is reverse transfer impedance obtained

when port-2 is open circuited and Z21 is forward transfer impedance obtained when port-1

is open circuited.

In Y-parameters the port Currents are expressed in terms of port voltages

and Y-parameters. The network is said to be symmetrical network when Y11=Y22 .The

network is said to be reciprocal network, when Y12=Y21Y12 is reverse transfer admittance

obtained when port-2 is short circuited and Y21 is forward transfer admittance obtained

when port-1 is short circuited.



22

PROCEDURE:

Z-parameters:


2) Fix the voltage to 20v and record the readings I1 and V2

3) Calculate Z11 and Z21



6) Calculate Z12 and Z22

Y-parameters:


2) Fix the voltage to 20v and record the readings I1 and I2

3) Calculate Y11 and Y21



6) Calculate Y12 and Y22


Z-parameters:

V1 = Z11I1 + Z12I2

V2 = Z21I1 + Z22I2

By open circuiting the port-2, I2=0

Z1=R1+R2

I1=

1

1

Z

V

Z11= 1

1

I

V= R1+R2

V2=I1 x R2

Z21= 1

2

I

V= R2

By open circuiting the port-1, I1=0

Z2=R2+R3

I2=

2

2

Z

V

Z22=

2

2

I

V = R2+R3

V1=I2 x R2



23

Z12=

2

1

I

V= R2

Y-parameters:

I1 = Y11V1 + Y12V2

I2 = Y21V1 + Y22V2

By short circuiting the port-2, V2=0

Z == 32

133221

RR

RRRRRR

I1=

1

1

Z

V=

Y11=

1

1

V

I =

133221

32

RRRRRR

RR

I2 = - I1 x32

2

RR

R

Y21= -1

2

V

I = -

133221

2

RRRRRR

R

By short circuiting the port-1, V1=0

Z2 == 21

133221

RR

RRRRRR

=

I2 =

2

2

Z

V

I1= - I2 x 21

1

RR

R

Y12= -

2

1

V

I = -

133221

1

RRRRRR

R

Y22=

2

2

V

I=

133221

21

RRRRRR

RR



24

TABULAR COLUMN:

Z-parameters:

S.NO V1(V) V2(V) I1(Amp) I2(Amp)

Y-parameters:


CAMPARISION:

PARAMETER THEORETICAL VALUE PRACTICAL VALUE

RESULT:Z and Y parameters are determined for the given circuit and theoretical

&practical values are compared







VIVA-VOCE:1)What is a port ?

2) What are basic equations for Z & Y parameters?

3) What are the applications of Z&Y parameters?

4) What is the condition for reciprocity & symmetry in Z-parameters?

5) What is the condition for reciprocity & symmetry in Y-parameters?



25

EXPERIMENT-7

TRANSMISSION AND HYBRID PARAMETERS

AIM: To determine Transmission and hybrid parameters for a given Two port network.

APPARATUS: 1) Rheostats-

2) Voltmeter

3) Ammeter


5) Connecting wires

CIRCUIT DIAGRAM:

Transmission parameters

To find A & C parameters:

CKT-1

To find B & D parameters:

CKT-2



26

Hybrid parameters:

To find h11 & h21:

CKT-1

To find h12 & h22:

CKT-2

THEORY:

Transmission parameters:

In transmission parameters the voltage &current at port -1 are

expressed in terms of voltage and current at port -2 and is given by the following

equations.

V1 = AV2 - BI2

I1 = CV2 - DI2

Here A, B, C,D are the transmission parameters or chain parameters or general circuit

parameters. The –ve sign in the second term is for I2 and not for parameters B and D .

The negative sign is due to the opposite direction of I2. In transmission parameters V1,I1

are dependant voltage and current sources and V2,I2 are independent voltage and current

sources. APPLICATION: Transmission line parameters are used to find the performance of the

transmission line i.e. Efficiency & Regulation.



27

Hybrid parameters: The hybrid parameters contain dependant voltage and current sources and independent

voltage and current sources.

APPLICATION: Hybrid parameters find extensive use in transistor circuits

PROCEDURE:




3) Calculate A and C



6) Calculate B and D

Hybrid parameters: 1) Connect the circuit as per circuit diagram.(1)


3) Calculate h11 and h21



6) Calculate h12 and h22



V1 = AV2 - BI2

I1 = CV2 - DI2

By open circuiting port-2,I2=0

Z1=R1+R2=

I1=

1

1

Z

V=

V2=I1 x R2 =

A =2

1

V

V =

2

21

R

RR =

C =2

1

V

I =

2

1

R=

By short circuiting port-2,V2=0

Z =32

133221

RR

RRRRRR



28

I1=

1

1

Z

V=

I2=I1 x 32

2

RR

R

=

B = - 2

1

I

V =

2

133221

R

RRRRRR =

D = -2

1

I

I=

2

32

R

RR =

Hybrid parameters:

V1 = h11I1 + h12V2

I2 = h21I1 + h22V2

By short circuiting port-2,V2=0

Z1 == 21

21

RR

RR

=

I1=

1

1

Z

V=

I2= I1 x21

1

RR

R

=

h11 =1

1

I

V =

21

21

RR

RR

=

h21 =1

2

I

I =

21

1

RR

R

=

By open circuiting port-1,I1=0

Z2 == 321

1332

RRR

RRRR

=

I2 =

2

2

Z

V=

I1=I2 x 321

3

RRR

R

=

V1=I1 x R1=



29

h12 =2

1

V

V=

3231

31

RRRR

RR

=

21

1

RR

R

=

h22 =2

2

V

I=

3231

321

RRRR

RRR

=

TABULAR COLUMN:



Hybrid parameters:


CAMPARISION:


RESULT: Transmission and Hybrid parameters are determined for the given circuit and

theoretical &practical values are compared.




Position before and after switch on the supply



VIVA-VOCE:1)What is a port ?

2) What are basic equations for transmission & hybrid parameters?

3) What are the applications of transmission & hybrid parameters?

4) What is the condition for reciprocity & symmetry in transmission?

Parameters?

5) What is the condition for reciprocity & symmetry in Hybrid -

Parameters?

6) What are the units for each parameter in transmission & hybrid?

Parameters?



30

EXPERIMENT-8

THEVENIN’S AND NORTON’S THEOREMS

AIM: To verify the Thevenin’s &Norton’s theorems.


2) Voltmeter

3) Ammeter


5) Connecting wires

CIRCUIT DIAGRAM:

To find Vth:

CKT-1

To find Isc:

CKT-2



31

To find IL:

CKT-3

THEORY:

Thevenin’s theorem states that any linear active bilateral network can be replaced by an

emf

acting in series with an impedance .The emf is the open circuited voltage Vth at the

terminals and the impedance Zth is input impedance at the terminals when all the sources

in the network have been replaced by their internal impedances.

Norton’s theorem states that any linear active bilateral network can be replaced by with

an equivalent circuit consisting of a current source IN in parallel with an impedance ZN

.The IN is the short circuit current between the terminals and the impedance ZN is input

impedance at the terminals when all the sources in the network have been replaced by

their internal impedances.

PROCEDURE:1)Connections are made as per the circuit diagram (1)

2) For different voltages of V1 record VOC = Vth

3) Connections are made as per the circuit diagram (2)

4) For the same different voltages of V1 record ISC.

5) Connections are made as per the circuit diagram (3)

6) For the same different voltages of V1, measure and record IL.


Thevenin’s theorem:

Step: 1To find Rth :

Short circuit voltage source, open circuit load resistance and determine the driving point

impedance.

Rth == 21

133221

RR

RRRRRR

=



32

Step: 2 To find Vth :

Open circuit load resistance only.

Z = R1 + R2 =

I =

Z

V1=

Vth =I x R2 = V1 x 21

2

RR

R

=


IL = Lth

th

RR

V

=

EQUIVALENT CIRCUIT:

Norton’s theorem:

Step: 1To find RN :

Short circuit voltage source, open circuit load resistance and determine the input

impedance.

RN == 21

133221

RR

RRRRRR

=

Step: 2To find Isc :

Short circuit the load resistance only.

Z =32

133221

RR

RRRRRR

=

I =

Z

V1=



33

Isc =I2 =I x 32

2

RR

R

=


IL = Isc x LN

N

RR

R

=

EQUIVALENT CIRCUIT:

TABULAR COLUMN:

Thevenin’s theorem:

S.NO V1(V) V2(Vth) Rth IL(Amp)

Norton’s theorem:

S.NO V1(V) Isc RN IL(Amp)

CAMPARISION:


RESULT: Thevenins and Norton’s theorems are verified for the given circuit.




Position before and after switch on the supply





34

VIVA-VOCE:1)State Thevenin’s theorem?

2) State Norton’s theorem?

3) What are the applications of Thevenin’s & Norton’s theorem?

4) What are limitations of Thevenin’s & Norton’s theorem?



35

EXPERIMENT-9

LOCUS DIAGRAM

AIM: To draw Loci of impedance, admittance &current for an RL circuit with a variable

inductance and fixed resistance.

APPARATUS:1)1-Ø Varaic.

2) Resistance –

3) Voltmeter –

4) Ammeter

5) Wattmeter

6) Inductance

CIRCUIT DIAGRAM:

THEORY:

A Phasor diagram may be drawn and is expanded to develop a curve; Known

as a locus. Locus diagrams are useful in determining the behaviour or response of an

RLC circuit when one of its parameters is varied while the frequency and voltages are

kept constant. The magnitude and phase of the current vector in the circuit depends upon

the values of R, L, C and frequency at a fixed source voltage. The path traced by the

terminus of the current phasor when the parameter is either R or L varied while f and V

are kept constant is called the current locus.

Locus diagrams are also be drawn for impedance & admittance when frequency is

variable.

PROCEDURE:1) Connect the circuit as per circuit diagram.

2) Keep the Inductance in the minimum position

3) Apply a voltage of 80V.

4) Record the voltmeter, ammeter &wattmeter readings.

5) Vary the Inductance in such a way that the current variation follows

Some sequence.

6) At every current, note down voltmeter, Ammeter & wattmeter

readings



36

EXPECTED GRAPHS:



37

TABULAR COLUMN:

S.NO L V I P COSØ Z G=

22

LXR

R

B=

22

L

L

XR

X

Ø=COS-1 (

VI

P)

RESULT: Locus diagrams for impedance, admittance &current for an RL circuit with

variable inductance and fixed resistance are drawn



3) Always kept the variac output voltage in minimum




VIVA-VOCE:1)What is meant by locus diagram?

2) What is the difference between locus diagram& phasor diagram?

3) To draw the locus diagrams which parameters are kept constant?

4) What happens when resistance varies &inductance kept constant?



38

EXPERIMENT-10

COMPENSATION THEOREM

AIM: To verify the Compensation theorem.


2) Voltmeter

3) Ammeter


5) Connecting wires

CIRCUIT DIAGRAM:

CKT-1

CKT-2

CKT-3



39

THEORY: The compensation theorem states that any element in the linear bilateral

network may be replaced by a voltage source of magnitude equal to the current passing

through the element, provided the currents and voltages in other part of the circuit remain

unaltered. This theorem is useful in finding the changes in current or voltage when the

value of resistance is changed in the circuit.

PROCEDURE: 1) Connect the circuit as per the circuit diagram (1).

2) Fix the voltage V1 and note down the reading Ix.

3) Connect the circuit as per the circuit diagram (2).

4) Fix the voltage Vc and note down the reading IY

5) Connect the circuit as per the circuit diagram (3)

6). Fix the voltage V1 and Vc and note down the reading Ix -. IY

TABULAR COLUMN:

S.NO

RESULT: Hence compensation theorem is verified.







VIVA-VOCE:1)State compensation theorem?

2) What are the applications of compensation theorem?

3) What are the limitations of compensation theorem?

Documents

ELECTRICAL CIRCUITS LAB MANUAL · 4) maximum power transfer theorem 5) verification of superposition theorem and reciprocity theorem 6) impedance and admitance parameters 7) transmission