electrical circuits and simulation lab 2011-12...

Electrical Circuits & Simulation Lab i EEE-Department

ELECTRICAL CIRCUITS AND SIMULATION LAB

DEPARTMENT OF

ELECTRICAL AND ELECTRONICS ENGINEERING

ACADEMIC YEAR 2011-2012

II B.Tech II SEMESTER

PADMASRI DR B. V. RAJU INSTITUTE OF TECHNOLOGY

VISHNUPUR, NARSAPUR, MEDAK (DIST.) – 502 313

Phone No: 08458 – 222031, www.bvrit.ac.in

Electrical Circuits & Simulation Lab ii EEE-Department

PREFACE

The significance of the Electrical Circuits and Simulation Lab is renowned in the

various fields of engineering applications. For an Electrical Engineer, it is

obligatory to have the practical ideas about the Electrical Circuits and Simulation.

By this perspective we have introduced a Laboratory manual cum Observation for

Electrical Circuits and Simulation.

The manual uses the plan, cogent and simple language to explain the fundamental

aspects of Electrical Circuits and Simulation in practical. The manual prepared

very carefully with our level best. It gives all the steps in executing an experiment.

Electrical Circuits & Simulation Lab iii EEE-Department

ACKNOWLEDGEMENT

It is one of life’s simple pleasures to say thank you for all the help

that one has extended their support. I wish to acknowledge and appreciate

Assoc Prof J Bangarraju, P PrabhuDass, K Srinivasa Raju and G Suresh Raju

for their sincere efforts made towards developing the Electrical Circuits and

Simulation lab manual. I wish to thank students for their suggestions which

are considered while preparing the lab manuals.

I am extremely indebted to Sri. Col Dr. T. S. Surendra, Principal

and Professor, Department of Electrical and Electronics Engineering, BVRIT for

his valuable inputs and sincere support to complete the work.

Specifically, I am grateful to the Management for their constant

advocacy and incitement.

Finally, I would again like to thank the entire faculty in the

Department and those people who directly or indirectly helped in successful

completion of this work.

Prof. N. BHOOPAL

HOD-EEE

Electrical Circuits & Simulation Lab iv EEE-Department

GUIDELINES TO WRITE YOUR OBSERVATION BOOK 1. Experiment Title, Aim, Apparatus, Procedure should be on right side. 2. Circuit diagrams, Model graphs, Observations table, Calculations table should be left side. 3. Theoretical and model calculations can be any side as per your convenience. 4. Result should always be in the ending.

5. You all are advised to leave sufficient no of pages between experiments for theoretical or model calculations purpose.

Electrical Circuits & Simulation Lab v EEE-Department

LAB CODE 1. Students should report to the concerned labs as per the time table schedule.

2. Students who turn up late to the labs will in no case be permitted to perform the experiment scheduled for the day.

3. After completion of the experiment, certification of the concerned staff in-charge in the observation book is necessary.

4. Students should bring a note book of about 100 pages and should enter the readings/observations into the note book while performing the experiment.

5. The record of observations along with the detailed experimental procedure of the experiment performed in the immediate last session should be submitted and certified by the staff member in-charge.

6. Not more than three students in a group are permitted to perform the experiment on a setup.

7. The group-wise division made in the beginning should be adhered to, and no mix up of student among different groups will be permitted later.

8. The components required pertaining to the experiment should be collected from stores in-charge after duly filling in the requisition form.

9. When the experiment is completed, students should disconnect the setup made by them, and should return all the components/instruments taken for the purpose.

10. Any damage of the equipment or burn-out of components will be viewed seriously either by putting penalty or by dismissing the total group of students from the lab for the semester/year.

11. Students should be present in the labs for the total scheduled duration.

12. Students are required to prepare thoroughly to perform the experiment before coming to Laboratory.

13. Procedure sheets/data sheets provided to the students’ groups should be maintained neatly and to be returned after the experiment.

Electrical Circuits & Simulation Lab vi EEE-Department

JAWAHARLAL NEHRU TECHNOLOGICAL

UNIVERSITY HYDERABAD

II Year B.Tech. EEE-II Semester L T/P/D C

0 -/3/- 2

(54603)ELECTRICAL CIRCUITS & SIMULATION LAB

PART-A: ELECTRICAL CIRCUITS

1) Thevinin’s and Norton’s and Maximum Power Transfer theorems.

2) Superposition theorem and RMS value of complex wave.

3) Verification of compensation theorem.

4) Reciprocity and Millman’s theorems

5) Locus diagram of RL & RC series circuits.

6) Series and Parallel resonance.

7) Determination of self and mutual inductances and co efficient of coupling.

8) Z and Y Parameters.

9) Transmission and hybrid parameters.

10) Measurement of Active power for Star and Delta connected balanced loads

11) Measurement of Reactive power for Star and Delta connected balanced loads.

12) Measurement of 3-phase power by two watt meter method for unbalanced loads.

PART-B: PSPICE SIMULATION

1) Simulation of dc circuits

2) DC Transient response

3) Mesh analysis

4) Nodal analysis

NOTE:

• PSPICE Software Package is necessary.

• Eight experiments are to be conducted from PART-A and any two from PART-B

Electrical Circuits & Simulation Lab vii EEE-Department

INDEX

PART-A: ELECTRICAL CIRCUITS PG.No

1 Thevinin’s and Norton’s and Maximum Power Transfer theorems. 1

2 Superposition theorem and RMS value of complex wave. 10

3 Verification of compensation theorem. 15

4 Reciprocity and Millman’s theorems. 17

5 Locus diagram of RL & RC series circuits. 20

6 Series and Parallel resonance. 24

7 Determination of self and mutual inductances and co efficient of coupling.

29

8 Z and Y Parameters. 32

9 Transmission and hybrid parameters. 36

10 Measurement of Active power for Star and Delta connected balanced loads.

40

11 Measurement of Reactive power for Star and Delta connected balanced loads.

44

PART-B : PSPICE SIMULATION

1 Simulation of DC Circuits. 47

2 DC Transient response. 48

3 Mesh Analysis. 54

4 Nodal Analysis. 57

ADDITIONAL EXPERIMENTS

1. Time response of first order for RC & RL Circuits. 59

2. Verification of KVL and KCL. 62

Electrical Circuits & Simulation Lab 1 EEE-Department

₋

₊

DM

_

+

Vs

+ +

A

R1

_ +

Vth

_ +

+

_

V

1. THEVENIN’S , NORTON’S THEOREM AND MAXIMUM POWER TRANSFER

THEOREM.

CIRCUIT DIAGRAMS FOR THEVININ AND NORTON’S:-

Fig-1(Original circuit)

Fig-2 (Finding Rth)

R2

R3

RL

R2

RL

R2 Vs

R1 R3

R1 R3


-

+

₊

₋

+

+

_

A

₋

₊

Isc _ +

+

_

A

₋₊

+

+

_

A

Fig-3 (Finding Vth)

Fig-3 (Finding IL)

Fig-4 (Finding Isc)

S

V

R2

RL

Vs

R2 Vs

Vth

R1 R3

R1 R3

Rth RL


- +

-

+

Fig-5 Circuit diagram for Thevenin’s equivalent circuit.

Fig-5 Circuit diagram for Norton’s equivalent circuit.

CIRCUIT DIAGRAM FOR MAXIMUM POWER TRANSFER THEOREM:-

RN

RL

A

A

IN


1. THEVENIN’S , NORTON’S THEOREM AND MAXIMUM POWER TRANSFER

THEOREM.

AIM: Experimental determination of Thevenin’s and Norton’s equivalent circuits and

verifying theoretically and practically and To verify maximum power transfer theorem

theoretically and practically.

.

APPARATUS:

S.No Name of the equipment Range Type Quantity

1.

2.

3.

4.

5.

6.

THEORY:

STATEMENT OF THEVENIN’S THEOREM:

Any two terminal linear bilateral network containing of energy sources and impedances can be

replaced with an equivalent circuit consisting of voltage source Vth in series with an impedance, Zth.,

where Vth is the open circuit voltage between the load terminals and Zth is the impedance measured

between the terminals with all the energy sources replaced by their internal impedances.

STATEMENT OF NORTON’S THEOREM:

Any two terminal linear bilateral network containing of energy sources and impedances can be

replaced with an equivalent circuit consisting of current source IN in parallel with an admittance, YN.,

where IN is the short circuit current through the load terminals and YN is the admittance measured

between the terminals with all the energy sources replaced by their internal admittance.


CALCULATIONS FOR THEVENIN’S AND NORTON’S THEOREMS:-

(i) For Rth- As for the circuit diagram, fig-2, Resisters R1 and R2 are in parallel so effective

Resistance Rp = R1 × R2 ÷ R1 + R2 Ω.

Then Rp is in series with R3, so Rth = Rp +R3 Ω.

(ii) For Vth - As for the circuit diagram, fig-3, Resisters R1 and R2 are in series so total

Resistance R = R1 + R2 Ω. (R3 Will not play any roll because of open circuit.)

Total current of the circuit I = Vs ÷ R Amp.

The current I will flow through R1 and R2 because of series connection.

Then open circuit voltage Vth = I× R2 Volts.

(iii) For IL- As for the circuit diagram, fig-1, Resisters R3 and RL are in series so effective

Resistance Rse = R3 +RL Ω.

Then Rse is in parallel with R2 so effective

Resistance Rp = Rse × R2 ÷ Rse + R2 Ω.

Then Rp is in series to R1 resistance so total Resistance R = Rp + R1 Ω.

Total current of the circuit I = Vs ÷ R Amp .

Total current of the circuit I is divided in to two paths after R1 resistance

So the current through RL resistance branch

IL =( Total current) I × opposite resistance ÷ total Resistance --Amp

(iv) For Isc or IN - As for the circuit diagram, fig-4, Resisters R2 and R3 are in parallel so effective

Resistance Rp = R2× R3 ÷ R2 + R3 Ω.

Then Rp is in series to R1 resistance so total Resistance R = Rp + R1 Ω.

Total current of the circuit I = Vs ÷ R Amp.

Total current of the circuit I is divided in to two paths after R1 resistance

So the current through R3 resistance branch


Isc =( Total current) I × opposite resistance ÷ total Resistance –Amp.

Tabulation-

Rth Vth IL Isc or IN

Theoretical Practical Theoretical Practical Theoretical Practical Theoretical Practical

Thevenin’s equalent circuit. Norton’s equalent circuit.

STATEMENT FOR MAXIMUM POWER TRANSFER THEOREM:

It states that the maximum power is transferred from the source to the load, when the load

resistance is equal to the source resistance.

THEORETICAL CALCULATIONS:

PROCEDURE:

Make the connections as shown in fig (1).

By varying RL in steps, note down the reading of ammeter IL in each step.

Connect the circuit as shown in fig (2), measure the effective resistance Rth.

with the help of digital multimeter.

Calculate power delivered to load PL in each step.

Draw a graph PL Vs RL and find the RL corresponding to maximum power from it.

Verify that RL corresponding to maximum power from the graph is equal to the Rth( which is nothing but

source resistance RS).

IL’

Theoretical Practical

IL’’

Theoretical Practical


MODEL GRAPH

OBSERVATIONS:

Tabular column:

Theoretical values

Practical values

S.No

RL

IL

PL= IL2RL

IL

PL= IL2RL

PRECAUTIONS:

1. Avoid making loose connections.

2. Readings should be taken carefully with out parallax error.

3. Avoid series connection of voltmeters and parallel connection ammeters.

RESULT: Verified theoretically and practically Load current by using Thevinin’s and Norton’s theorems

and also verified Maximum Power Transfer Theorem

RL RL corresponding to Pm

Pm

PL


2. SUPER POSITION THEOREM AND RMS VALUE OF COMPLEX WAVE:-

Circuit Diagram of Super Position Theorem:-


230 115

(0-50)V

MI

1- Φ

230V

50 Hz

AC

Supply

Ph

N 1 Φ -

Transformer

DPST

Variac

3KVA, 230V/ (0-

V

C R O

100Ω/5A

Circuit Diagram of RMS value of complex wave.


2. SUPER POSITION THEOREM AND RMS VALUE OF COMPLEX WAVE:-

AIM: Verification of Superposition theorem and To experimentally determine the RMS value of

a complex wave.

APPARATUS:


1.

2.

3.

4.

5.

THEORY:

SUPERPOSITION THEOREM STATEMENT

In any linear bilateral network containing two or more energy sources the response at any

element is equivalent to the algebraic sum of the responses caused by the individual sources.

i.e. While considering the effect of individual sources, the other ideal voltage sources and ideal current sources in the network are replaced by short circuit and open circuit across the terminals. This theorem is valid only for linear systems.

PROCEDURE:

SUPERPOSITION THEOREM:

1. Connect the circuit as shown in fig (1)

2. Current through load resistor is noted as IX by applying both the voltages V1 and

V2 through RPS.

3. Make the supply voltage V2 short circuited and apply V1 as shown in fig (2) and note down the current

through load resistor as IY.


4. Make the supply voltageV1 short circuited and apply V2 as shown in fig (3) and note down the current

through load resistor as IZ.

5. Now verify that IX = IY + IZ theoretically and practically which proves Superposition

Theorem

Procedure:-

1). Connect the circuit as for the fig (1).

2). Switch on the AC supply and observe the wave form in the C R O.

3). Take the wave form on tracing paper and draw it on the graph paper.

4). By dividing the time period of the wave form into equal intervals,

note down the voltage and time at each interval.

5). Calculate the form factor, Peak factor and RMS value.

Observations:

When both the sources are acting: fig (1) When V1 source alone is

acting: fig (2)

When V2 source alone is acting: fig (3)

V1

V2

Theoretical

IX

Practical

IX

V1

V2

Theoretical

IZ

Practical

IZ

V1

V2

Theoretically

Practical I


Observations from the graph:-

S.No Voltage(v) Time(t)

Model Calculations:-

Average value= v1+v2+---------vn÷n.

R M S Value=√ v12+v2

2+----------vn

2÷n.

Expected graph:-

PRECAUTIONS:


2. Readings should be taken carefully with out parallax error.


RESULT: - Verified Superposition theorem and determined the RMS voltage of a complex

wave.


RL

-

+

220v _

+

A

R

RL

-

+

VC=I2 ΔR _

+

A

RL+ΔR

-

+

220v_

+

A

R

3. VERIFICATION OF COMPENSATION THEOREM.

CIRCUIT DIAGRAM FOR VERIFICATION OF COMPENSATION THEOREM:-


3. VERIFICATION OF COMPENSATION THEOREM

Aim:-To verify Compensation theorem theoretically and practically.

Apparatus Required:


1.

2.

3.

4.

5.

THEORY:-Compensation theorem states that in a linear network any impedance Z that carries a current

‘I’ can be replaced by a voltage source with emf V=IZ with zero internal impedance. Similarly if the

voltage across impedance V, then it can be replaced by a current source I=V/Z.

Procedures:-

• Connect the circuit as in the fig (1).

• Switch on the power supply and note down the readings of ammeter (I1).

• Connect the circuit as in the fig (2) with increase value of resistance.

• Switch on the power supply and note down the readings of ammeter (I2).

• Connect the circuit as in the fig (3)

• Switch on the power supply and note apply compensated voltage Vc=-I2 ΔR

and note down the readings of ammeter (I3 ).

Result:-Verified Compensation Theorem Theoretically and Practically.


VS +

_

+

A

RL

-

+

Veq

_

+

Req

A

Dmm(Req)

D

Veq

-

+

+

_

+

v

4. RECIPROCITY THEOREM, MILLMAN’S THEOREM.

CIRCUIT DIAGRAM FOR MILLMAN’S THEORM:-


4. VERIFICATION OF RECIPROCITY AND MILLMAN’S THEOREMS.

Aim:- To verify Reciprocity and Millman’s theorems theoretically and practically.

Apparatus:-


1.

2.

3.

4.

5.

THEORY:-

Reciprocity theorem:- In a linear bilateral single source network if voltage at any point in the network

produces a current at same other point in the network , the same votage at other point produces same

current at the first point in that net work.

Millman’s theorem:- Consider the N no of voltage sources (V1,V2-------Vn) having a series

impedance(Z1,Z2-------Zn) are connected parallel as shown according to Millman’s theorem all the

voltage source of the current can be represented as a single voltage can be in series with the impedance

.

Veq=(V1G1+V2G2+V3G3)/(G1+G2+G3)

Req=1/(G1+G2+G3)

Procedure:-

Reciprocity theorem-

1. Connect the circuit as shown in fig (1)

2. From fig (2) of Superposition theorem note down I2=IY.

3. Now interchange the source and ammeter as in fig (4).


4. Note down the ammeter reading as I1.

5. Now verify that Vs/ I1 = Vs/ I2 theoretically and practically which proves reciprocity

theorem.

TABULAR COLUMN OF RECIPROCITY THEOREM:

Before interchanging the sources: fig (1)

After interchanging the sources: fig (4)

Millman’s theorem:-

• Connect the circuit as in the fig (1).

• Set the supply voltage as shown in circuit diagram.

• Note the reading ammeter (I2).

• Connect the circuit as in the fig (2). Note the reading of voltmeter (veg).

• Connect the circuit as in the fig (3) measure the equivalent resistance as Reg with

help of multi meter.

• Connect the circuit as in the fig (4), Apply (veg). From source, see Reg value.

• Note the reading of Ammeter as (I1

2).

• Now verify IL= I1

L Thus the Millman’s therem is verified.

Result:- Verified Reciprocity & Millman’s theorems theoretically and practically.

Theoretical values Practical values

Vs

I2

Vs/ I2

I2

Vs/ I2

Theoretical values Practical values

Vs

I1

Vs/ I1

I1

Vs/ I1


(0-2.5)A

MI

(0-300V

MI)

1- Φ

230V

50 Hz

AC

Suppl

y

P

N

100Ω/5A

DPST

Variac

3KVA, 230V/ (0-

5A, 150V, UPF

LM

C

V

Fig -

V

A

(0-2.5)A

MI

(0-300V

MI)

1- Φ

230V

50 Hz

AC

Suppl

y

P

N

100Ω/5A

DPST

Variac

3KVA, 230V/ (0-

5A, 150V,UPF

LM

C

V

Fig -

V

A

5. LOCUS DIAGRAMS OF RL AND RC SERIES CICUITS.

CIRCUIT FOR CURRENT LOCUS DIAGRAM FOR CAPACITIVE CIRCUIT:-

CIRCUIT DIAGRAM OF CURRENT LOCUS DIAGRAM FOR INDUCTIVE CIRCUIT:-


12

13

16 15 14

Model graph:-

11

xΩy y/r X6=0


5. LOCUS DIAGRAMS OF RL AND RC SERIES CICUITS.

AIM:-To draw the current locus of RL and RC circuits with L & C variables respectively.

APPARATUS:-


1.

2.

3.

4.

5.

6.

7.

PROCEDURE: -

RC circuit with ’C’ varying

1. All connections are made as per circuit diagram.

2. Rheostat is kept in maximum position. The capacitor varied step by step.

3. The corresponding ammeter, voltmeter and wattmeter readings are noted. ZcosΦ is constant. The

locus diagram is a semi circle of a diagram V/R.

RL Circuit with ’L’ varying

1. All Connections are made as per circuit diagram.

2. Rheostat is kept in maximum position. The inductor is varied step by step.

3. The corresponding ammeter, voltmeter and wattmeter readings are noted. ZcosΦ is constant. The

locus diagram is a semi circle of a diagram V/R.

Graph: A graph is drawn between ICosΦ & I SinΦ which given the current locus diagram of RL circuit.

The locus diagram is a semi circle with diameter V/XL.

Multiplication factor for wattmeter =

((Connected voltage X Connected current)/(Full scale reading of wattmeter)) X Cos Φ


Observations:

RL Circuits with L as variable:-

S.No V I W Z=V/I CosΦ=W/VI sinΦ ZcosΦ I CosΦ I SinΦ

RC Circuits with C as variable:-

S.No V I W Z=V/I CosΦ=W/VI sinΦ ZcosΦ I CosΦ I SinΦ

RESULT:- Current locus of “RL”and“RC” Circuits with “l” and “C” variables are drawn.


6. SERIES AND PARALLEL RESONANCE

CIRCUIT DIAGRAM OF SERIES RESONANCE:

CIRCUIT DIAGRAM OF PARALLEL RESONANCE:

A

Ip

Fig-2

Function

generato

A

Is

Function

generato

Fig-1


6. SERIES AND PARALLEL RESONANCE AIM: To verify resonant frequency, bandwidth & quality factor of RLC series and parallel

Resonant circuits.

APPARATUS:


1.

2.

3.

THEORY:

In a series RLC circuit. The current lags behind or leads the applied voltage depending upon the values of XL and Xc. XL causes the total current to lag behind the applied voltage while Xc causes the total current to lead the applied voltage.When XL > Xc the circuit is predominantly inductive, and when XL < Xc the circuit is predominantly capacitive. In the series RLC circuit resonance may be produced by varying the frequency keeping L and C constant. Otherwise resonance may be produced by varying either L or C for fixed frequency .Parallel resonance occurs when XL = Xc. when XL = Xc the two branch currents are equal in magnitude and 180 deg out of phase with each other .Hence two currents cancel each other and net current is zero.

PROCEDURE:

SERIES RESONANCE:

1. Connect the circuit as shown in the fig (1)

2. Apply a fixed voltage through function generator to the circuit.

3. The frequency of the signal is varied in steps and note down corresponding ammeter reading as Is.

observe that current is maximum at resonant frequency.

4. Draw a graph between frequency f and current Is .Mark Resonant frequency and

Current at half power frequencies.

12

0

ff

fQ

−=


maxI

f

2maxI

f1 fo f2

IS

5. Find Bandwidth = (f2-f1.) & Quality factor from graph.

6. Compare practical values of resonant frequency, Q-factor and Bandwidth with theoretical values.

PARALLEL RESONANCE:

1. Connect the circuit as shown in the fig (2)

2. Apply a fixed voltage through function generator to the circuit.

3. The frequency of the signal is varied in steps and note down corresponding ammeter reading as Is.

Observe that current is minimum at resonant frequency.

4. Draw a graph between frequency f and current Is .Mark resonant frequency and

current at half power frequencies.

5. Find Bandwidth = (f2-f1.) & Quality factor from graph.

6. Compare practical values of resonant frequency, Q-factor and Bandwidth with theoretical values.

MODEL GRAPH:

OBSERVATIONS:

series resonance

S.No. Frequency

(f) Current(Is)

12

0

ff

fQ

−=


MODEL GRAPH: Parallel resonance

OBSERVATIONS Parallel resonance:

RESULT TABLE:

S.No. Frequency (f)

Current(Is)

Series Resonance Parallel Resonance

Theoretical Practical Theoretical Practical

Resonant frequency

Bandwidth

Q-factor

IP

ff2f1 fo

minI

min2I


PRECAUTIONS:


2. Readings should be taken carefully without parallax error.


RESULT: Resonant frequency, Bandwidth and Quality factor of R L C Series and parallel resonant circuits

are calculated.


(0-300V)MI

230V 115VV (0-2)A

MI

(0-300)V

MI

1- Φ

230V

50 Hz AC

Supply

Ph

N1 Φ -Transformer

3KVA, 230V/ 115V

DPST

Variac

3KVA, 230V/ (0-270)V

LM

C

V

Fig -2 To find L2, M,K

V

A

V

2A,300V, 60W, LPF

(0-2)A

MI

(0-150)V

MI

1- Φ

230V

50 Hz AC

Supply

Ph

N

115VV 230VV

1 Φ -Transformer

3KVA, 230V/ 115V

DPST

Variac

3KVA, 230V/ (0-270)V

2A, 150V, 60W, LPF

LM

C

V

Fig -1 To find L1

V

A

V

7. Determination of self, Mutual Inductances and Coefficient of coupling.

CIRCUIT DIAGRAM:-

7.


Determination of self, Mutual Inductances and Coefficient of coupling.

AIM:- To determine the self mutual induction of coupled circuit and to find coefficient coupling.

Apparatus:-


1.

2.

3.

Procedure:

1. To find the inductance of coil-1:

a) All the connections are made as per the circuit diagram.

b) To determine L, the resistance R1 of coil is neglected.

c) The Supply voltage is given and the reading of the voltmeter and ammeter are noted

L1= x/2 Πf

when X1=V1/I1.

2. To find Self inductance of coil – 2:

a) The determine L2 remove the connections by interchanging the windings as per the circuit diagram

II. The voltage given and by varying dimmer stat required voltage is applied to coil and the readings of

ammeter and voltmeter are noted.

L2 = X2 / 2 Πf, X2 = V2/I2

3. To find mutual inductance:

a) All the connections are made as per the circuit diagram.

b) The supply voltage is given by varying the dimmer stat and the reading of a ammeter and

voltmeter are noted.

M = -1/2[X3/2 Πf – (L1+L2)]

Where X3 = V3 / I3

Coefficient of coupling K= M/sqrt(L1L2)


OBSEVATION TABLE:-

S.No V1 V2 Wi Io COSФ= Wi/ V1* Io Iµ=IoSINФo

S.No V1 V2 Wi I0 COSФ= Wi/ V1* Io Iµ=IoSINФo

Result: Experimentally calculated Self and Mutual Inductances of the Coil.


₋

₊

Vs2 +

+

_

₊

₋

V

+

_

V

8. Z and Y Parameters.

Circuit Diagram Z and Y PARAMETERS

CIRCUIT DIAGRAM:-

Fig-1

CALCULATION OF Z11 AND Z21:-

Fig-2

R2

Vs1

R2

Vs1

A

V2

I1


₊

₋

+

+

_

₊

₋

V

+

+

_

A

₊

₋

+

+

_

CALCULATION OF Z22 AND Z12 :-

Fig-3

CALCULATION OF Y11 AND Y21 :-

Fig-4

CALCULATION OF Y22 AND Y12 :-

Fig-5

R2

V1

A

V2

I2

+

++

-

V

R2

Vs1

A

I2

I1

R2

I1

A

V2

I2

+

++

-

A


8. Z and Y PARAMETERS

AIM: To obtain experimentally Z parameters and Y parameters of a given two port network.

APPARATUS:


1

2

3

4

PROCEDURE:

1. Open Circuiting Output Terminals (I2 = 0):

Connections are made as per the circuit diagram shown in fig (2). Output terminals are kept Open via

a voltmeter. Supply is given to input port. Note the readings of ammeter as I1 and Voltmeter as V2.

2. Short circuiting output terminals (V2 = 0):

Connections are made as per the circuit diagram shown in fig (4). Output terminals are short circuited

via an ammeter. Supply is given to input port. Note the readings of ammeters as I1 and I2.

3. Open circuiting input terminals (I1 = 0):

Connections are made as per the circuit diagram shown in fig (3). Input terminals are kept open via an

voltmeter. Supply is given to output terminals. Note the readings of ammeter as I2 and voltmeter as V1.

4. Short circuiting input terminals (V1=0):

Connections are made as per the circuit diagram shown in fig (5). Input terminals are short circuited

via an ammeter. Supply is given to output port. Note the readings of ammeters as I1 and I2.

4. Calculate Z, Y Parameters values.


OBSERVATIONS:

When I1=0 When I2=0

S.No.

V1

I2

V2

When V1=0 When V2=0

S.No.

I2

I1

V2

RESULT TABLE:

Z Parameters Y Parameters

Z11 Z12 Z21 Z22 Y11 Y12 Y21 Y22

Theoretical

Practical

PRECAUTIONS: 1. Avoid making loose connections.



RESULT: Experimentally Determined Z and Y Parameters of Two Port Networks

S.No.

V1

I1

V2

S.No.

V1

I1

I2


₊

V V

+

₋_

₋

₊

Vs2 +

+

_

₊

₋

V

+

+

_

A

9. ABCD and h-Parameters.

CIRCUIT DIAGRAM:-

Fig-1

CALCULATION OF A AND C:-

Fig-2

CALCULATION OF B AND D :-

Fig-3

A

I1

V2 R2

Vs1

R2

Vs1

R2

Vs1

A

I2

I1


₊

₋

V

+

+

_

A

₊

₋

+

+

_

CALCULATION OF h11 AND h21 :-

Fig-4

CALCULATION OF h12 AND h22 :-

Fig-5

R2

Vs1

A

I2

I1

R2

V1

A

V2

I2 + +

+ -

V


9. ABCD AND HYBRID PARAMETERS

AIM: To obtain experimentally ABCD parameters and Hybrid parameters of a given two port network.

APPARATUS:


1

2

3

4

PROCEDURE:

1. To find A and C Parameters (I2 = 0):

Connections are made as per the circuit diagram shown in fig (2). Output terminals are kept Open via

a voltmeter. Supply is given to input port. Note the readings of ammeter as V1 and Voltmeter as V2.

2. To find B and D Parameters (V2 = 0):

Connections are made as per the circuit diagram shown in fig (3). Output terminals are short circuited

via an ammeter. Supply is given to input port. Note the readings of ammeters as I1 and V2.

3. To find h11 and h21 (V2 = 0):

Connections are made as per the circuit diagram shown in fig (4). Output terminals are short

circuited via an ammeter. Supply is given to input port. Note the readings of ammeters as I1 and V1.

4. To find h12 and h22 (I1 = 0):

Connections are made as per the circuit diagram shown in fig (5).Input terminals current is zero.

Supply is given to input port. Note the readings of ammeters as I1, V1

and I2.

5. ABCD, Hybrid parameters using formulae and verify them with theoretical values.


OBSERVATIONS:

When I1=0 When I2=0

S.No.

V1

I2

V2

When V1=0 When V2=0

S.No.

I2

I1

V2

RESULT TABLE:

PRECAUTIONS: 1. Avoid making loose connections.



RESULT: Experimentally Determined ABCD and h-parameters

S.No.

V1

I1

V2

S.No.

V1

I1

I2

ABCD Parameters Hybrid Parameters

A B C D h11 h12 h21 h22

Theoretical

Practical


10. MEASUREMENT OF ACTIVE POWER FOR STAR AND DELTA

CONNECTED NETWORK

(0-20)A

MI

W2

W1 M L

VC

M L

VC

(0-600)V

MI

A

V

R

Y

B

600V, 20A, UPF

110Ω

110Ω

110Ω

600V, 20A, UPF

Circuit for Star connected network:


(0-20)A

MI

W2

W1 M L

V C

M L

V C

(0-600)V

MI

A

V

R

Y

B

600V, 20A, UPF

73Ω

73Ω

73Ω

600V, 20A, UPF

Circuit for Delta connected network:


10. MEASUREMENT OF ACTIVE POWER FOR STAR AND DELTA CONNECTED NETWORK

Aim: To measure the active power for the given star and delta network.

Apparatus:

S.No Name of the equipment Range Type Quantity 1 Wattmeter 0-10A/600V MI 2 2 Rheostats 0-200 ohms Wire wound 3 3 Connecting wires - - As per the

requirement

Theory:

A three phase balanced voltage is applied on a balanced three phase load when the current in each of the phase lags by an angle Φ behind corresponding phase voltages. Current through current coil of w1=Ir, current through current coil of W2=IB, while potential difference across voltage coil of W1=VRN-VYN=VRY(line voltage), and the potential difference across voltage coil of W2= VRN-VYN=VBY.

Also , phase difference between IR and VRY is (300+ Φ).While that between IB and VBY is (300- Φ).

Thus reading on wattmeter W1 is given by W1=VRYIYCos(300+ Φ)

While reading on wattmeter W2 is given by W2=VBYIBCos(300- Φ)

Since the load is balanced, |IR|=|IY|=|IB|=I and |VRY|=|VBY|=VL

W1=VLICos(300+ Φ)

W2=VLICos(300- Φ).

Thus total power P is given by

W= W1 +W2 = VLICos(300+ Φ) + VLICos(300- Φ)

= VLI[Cos(300+ Φ) + Cos(300- Φ)]

= [√3/2 *2Cos Φ]VLI

= √3VLICos Φ.


Procedure:

(Star connection):

1) Connect the circuit as shown in the figure. 2) Ammeter is connected in series with wattmeter whose other end is connected to one of

the loads of the balanced loads. 3) The Y-phase is directly connected to one of the nodes of the 3-ph supply. 4) A wattmeter is connected across R-phase & Y-phase as shown in fig. The extreme of B-

phase is connected to the third terminal of the balanced 3-ph load. 5) Another wattmeter is connected across Y & B phase, the extreme of B-phase is connected

to the third terminal of the balanced three phases load. 6) Verify the connections before switching on the 3-ph power supply.

(Delta connection):

1) Connect the circuit as shown in the figure. 2) Ammeter is connected in series with wattmeter whose other end is connected to one of

the loads of the balanced loads. 3) The Y-phase is directly connected to one of the nodes of the 3-ph supply. 4) A wattmeter is connected across Y & B phase, the extreme of B-phase is connected to the

third terminal of the balanced 3-ph load. 5) Another wattmeter is connected across R & Yphase, the extreme of R-phase is connected

to the third terminal of the balanced three phases load. 6) Verify the connections before switching on the 3-ph power supply.

Precautions:

1. Avoid making loose connections. 2. Readings should be taken carefully without parallax error.

Result: Calculated Active and Reactive Powers for Star and Delta Networks


21

Fuse 10A

3 Φ –Auto Transformer

V

3-

Ф

I

N

D

U

C

T

I

V

E

L

O

V

A

M L

C

R

Y

B

N

11. Measurement of 3- Ф Reactive Power using 1- Ф Wattmeter

Circuit Diagram:-Measurement of 3- Ф Reactive Power using 1- Ф Wattmeter


11.Measurement of 3- Ф Reactive Power using 1- Ф Wattmeter

Aim:- Measurement of Reactive power of an 3- Ф balanced inductance load using one 1- Ф

Wattmeter.

Apparatus:-

Theory:-

For the measurement of reactive power in balanced 3-Ф circuit only a single Dynamometer

type wattmeter is required.

The current coil is connected in series with load and the pressure coil is connected across

the remaining two phase.

Let the current through current coil be Iph & potential appliance across the pressure coil

be “V”

VI=VY-VB=√3 VPH.

This potential VI is leading R by 90

oα IR by hence wattmeter reading indicates.

WI=√3 VPH IPH. Cos (-90

o+Ѳ)= =√3 VPH IPH sin Ѳ

Total reactive power (Q) obtained by Multiplying the wattmeter reading with =(-√3)i.e Q=√3 WI

Procedure:-

1) Connect the apparatus as shown as circuit diagram.

2) Vary the auto transformer and set it to rated voltage.

3) Now Vary the 3-Ф balanced load gradually.

4) Note down the reading of voltmeter, Ammeter & Wattmeter.

5) Calculate theoretical and Practical values of reactive power from the given formula.

S.NO Equipment Range Type Quantity

01

02

03

04

05

06

07


Precautions:-

1) Avoid lose connections.

2) Avoid parallax errors.

Result:-

The measurement of 3- Ф Reactive power using 1-Ф Wattmeter has been clone and

theoretical & practical values has been compared.

Observation Table:-

S.No W1 W2 Volts P=√3* W1 S=√3VI Ѳ=tan-1

(Q/P) Q=√3VI sin Ѳ Q=√S2-P2 I(Amps)

Result:- Reactive Power is Calculated by using Single Wattmeter Method


1. Simulation of DC Circuit using PSPICE

Aim:- To calculate current 6Ω branch using PSPICE simulation theoretically and practically.

Apparatus:- PSPICE Software.

Program:-

Vs 1 0 DC 50V

R1 1 2 30

R2 2 0 10

R3 2 3 20

R4 3 0 80

R5 3 0 6

.OP

.END

Result:-Branch current is calculated by using Simulation


₊

₋

+

+

2(a). Transient Response For PULSE INPUT

Circuit Diagram:-

1.

V1(V)

220V

-220V Tf Pulse width TR

t(ms)

V1

∫

R=2Ω L=50mH C=10µF


2(a). Transient Response for PULSE INPUT

Aim:- To find transient parametric analysis of a given RLC Circuit for pulse input.


Program:-

V1 1 0 PULSE (-220V 220V 0 2ns 2ns 50 ns 100ns)

R 1 2 2

L 2 3 50mH

C 3 0 10uH

. tran 1 Us 4uS

. plot tran v(3) V(1)

. probe

. End

Out put

Node voltages are node 1 0V

2 0V

3 0V

Currents 1) 0Amps

2 0Amps

Result: - Transient Response of RLC Circuit is observed for pulse input


₊

₋

+

+

2(b). Transient Response for Sinusoidal Input

Circuit Diagram:-

0

Model Graph:-

+20V

-20V

t

V1

20 Sinwt

∫



2(b). Transient Response for Sinusoidal Input

Aim:- To find transient parametric analysis of a given RLC Circuit for sinusoidal signal.


Program:-

V1 1 0 SIN ( 0 20V 10KHZ)

R 1 2 2

L 2 3 50mH

C 3 0 10uF

. tran 1uS 200uS


. probe

. End

Out put

Node voltages 1 0V

2 0V

3 0V

Currents 1 0Amps

2 0Amps

Result: - Transient Response of RLC Circuit is observed for Sinusoidal input


₊

₋

+

+

2(c). Transient Response For LINEAR INPUT

Circuit Diagram:-

V1(V)

20V

-20V

V1

∫



2. Transient Response for LINEAR INPUT

Aim:- To find transient parametric analysis of a given RLC Circuit with step input.


Program:-

V1 1 0 PWL ( 0 0 1ns 1V 2n1 w)

R 1 2 2

L 2 3 50mH

C 3 0 10uH

. tran 1us 400uS


. probe

. End

Out put

Node voltages 1 0V

2 0V

3 0V

Currents 1 0Amps

2 0Amps

Result: - Transient Response of RLC Circuit is observed for Linear input


IS

50mA

3

R2=200Ω

-

+

6

V5=OV

V3=0V

5

V4=0V

4

R450Ω R3800Ω

R1 1K

7

V2=0V

-

V1

20v

_

+

_

+

3. MESH ANALYSIS.

Circuit Diagram:-


3. MESH ANALYSIS.

AIM:-To find the node voltages, voltages, branch currents of a given circuit using mesh

analysis by PSPICE Software.


Program:-

V1 1 0 DC 20

V2 7 0 DC 0

V3 5 3 DC 0

V4 4 2 DC 0

V5 6 0 DC 0

IS 0 3 50

R1 2 7 1K

R2 3 6 200

R3 2 5 800

R4 1 4 500

.OP

.END


Out put

Node voltages voltage source current

1. 20.000 v3 -1.500 E -02

2. 12.5000 VX 1.250 E -02

3. 10.5000 Vy 2.500 E -03

4. 12.5000 V3 5.250 E -02

5. 10.5000 VA 1.500 E -02

6. 0.0000

7. 0.0000

The total power dissipation 3.00 E -01Watts.

Result: - Current and Voltage across the each branch is calculated by using Mesh

Analysis


0

3 2

41

-

+

V2

R2=8 Ω

R3=6 Ω

R1=10Ω R2 =16Ω

R4 12k

V1

30v

_

+

4. NODAL ANALYSIS.

Circuit Diagram:-


4. NODAL ANALYSIS.

AIM:-To find the node voltages, branch currents of a given circuit using nodal analysis by

PSPICE Software, and to verify them with theoretical values?


Program:- V1 1 0 DC 30

V2 4 0 DC 15

R1 1 2 10

R2 2 3 16

R3 3 4 6

R4 2 0 12

R5 3 0 8

.OP

.END

Out put

Node voltages 1). 30V

2). 14.66V

3). 9065V

4). 15V

The total power dissipation 5.91E+01Watts.

Result:- Current and Voltage across the each branch is calculated by using Nodal

Analysis


(0-1)mHZ

O/P

R=10Ω C R O

For R-L

(0-1)mHZ

O/P

L=10MH

R=10Ω C R O

For R-C

ADDITIONAL EXPERIMENTS

1. Time response of RL & RC Circuits.

Model graph:-


IN PUT RL & RC CKTS

OUTPUT RL CKT

OUT PUT RC CKT

T/2

4T

3T/2 T T/2

0

4T

T

T T/2

0

3T/2

T


1. Time response of RL & RC Circuits.

AIM:- To draw the time response of first order R-L & R-C Networks for periodic non sinusoidal functions

and determination of time constant.

APPARATUS:-


1.

2.

3.

4.

5.

PROCEDURE:-

1. Make connections as per the circuit diagram.

2. Give 2V Peak to peak square wave supply through function generator with suitable frequency.

3. Take out put across inductor in RL Circuit, across capacitor in RC Circuits.

4. Calculate the time constant from CRO.

5. For deferent values of T and V Calculate corresponding (L/R) Values.

6. Compare the time constant theoretically and practically.

OBSERVATIONS:-

RESULT:- Time Response of R-L and R-C Circuit was Observed.

Type of

circuit

Voltage Time period Time constant

Practical

Time constant

theoretical


₊

₊

+

Fig-1

VS

+

−

-

A

A

A

_

_

_

+

_ +

Fig-1

VS

+

−

V1

V

_ +

V

MC _

+ V

V

V22 MC V3 MC

VS

MC

2. VERIFICATION OF KVL AND KCL

CIRCUIT DIAGRAM OF KVL:-

CIRCUIT DIAGRAM OF KCL:-

A2-MC

A1-MC

A3-MC

R1

R2

R3


2. VERIFICATION OF KVL AND KCL

AIM:- Verification of KVL and KCL theoretically and practically.

APPARATUS:


1.

2.

3.

PROCEDURE:

KVL:- (1) Set the rheostats to given resistance values with the multimeter.

(2) Make connections as for diagram

(3) Verify the connections to the lab instructor.

(4) Switch on the DC supply with the help of DPST.

(5) Note down all meter readings, the sum of VI, V2 and V3 must be equal to the Vs.

KCL:- (1) Set the rheostats to given resistance values with the multimeter.

(2) Make connections as for diagram

(3) Verify the connections to the lab instructor.

(4) Switch on the DC supply with the help of DPST.

(5) Note down all meter readings, the sum of A2 and A3 must be equal to the A1.


CALCULATIONS:-

KVL-Total resistance of the circuit R =R1+R2+R3 -- Ω

Total current of the circuit I= Vs÷R -- Amp

The resistance are connected in series so the total current I will flow in every

Resistance. So

Voltage drop in resistance R1 = I × R1-------Volts.



Now Supply voltage Vs = (I × R1)+ (I × R2)+ (I × R3).

KCL- R2 and R3 resistances are in parallel so effective resistance Re = R2 ×R3÷ R3 +R2-- Ω.

Now R1 and Re are in series, so total resistance R = R1+Re --------- Ω.

Total current of the circuit I = Vs÷R -- Amp.

Current through R2 resistance I1 = Total current (I) ×Opposite resistance (R3) ÷

Total resistance (R2) + (R3) ------ Amps.

Current through R3 resistance I2 = Total current (I) - (I1) ---------- Amps.

Now Total current (I) = (I1) + (I2) ---------------------------------- Amps.

RESULT:-Verified KCL and KVL Theoretically and Practically.

electrical circuits and simulation lab 2011-12...

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