Cslab Expts New

EXPERIMENT – 1

TIME RESPONSE OF A SECOND ORDER SYSTEM

AIM: To study the time response of second order system.

APPARATUS:

1. Second order system kit2. Function Generator3. CRO4. Connecting wires

CIRCUIT DIAGRAM:

Fig: 1.1. Second Order System using RLC

THEORY:

PROCEDURE:

1. Apply square wave input of magnitude 5V peak to peak

2. Connect the output to CRO and measure the output voltage for various points.

3. Repeat for various values of ξ = 0.3, 0.7, 1, 2.

1

0 – 10 K

FORMULAE:

1. ωn = 1/√LC

2. ξ = (R/2) √(C/L)

3. tr = [(П – tan-1(√1-ξ2)/ ξ]/( ωn((√1-ξ2))

4. tp = П/ (ωn((√1-ξ2))

5. Mp = e((-Пξ)/( √1-ξ2))

6. td = (1+ 0.7 ξ)/ ωn

7. ts = 4/ ξωn for 2% tolerance band

GRAPHS:

Fig:1.2. Step Response of an under damped system

RESULT:

COMCLUSION:

2

Vol

tage

Time (msec)

0.5

ess

ts

1

EXPERIMENT - 2

CHARACTERISTICS OF SYNCHROS

AIM:

1. To study synchro transmitter.

2. To Study synchro transmitter and receiver pair.

APPARATUS:

1. Synchro transmitter Receiver pair trainer kit.

2. Patch chords.

PROCEDURE:

SYNCHRO TRANSMITTER

1. Connect the main supply to the system with the help of cable provided. Do not

interconnect S1, S2 and S3 to S11, S2

1, S31.

2. Switch ON main supply for the unit and transmitter rotor supply.

3. Starting from zero position, note down the voltage between stator winding

terminals ie., Vs1s2, Vs1s3, Vs2s3, in a sequential manner. Enter the readings in a

tabular form and plot the graph of angular position Vs rotor voltages for all the 3-

phases.

4. Note that zero position of the stator coincide with Vs3s1, voltage equal to zero

voltage. Do not disturb this condition.

SYNCHRO TRANSMITTER RECEIVER PAIR

1. Connect the main supply cable

2. Connect S1, S2 , S3 terminals transmitter to S1, S2, S3 of synchro receiver by patch

chords provided respectively.

3. Switch ON rotor supply of both transmitter and receiver and also switch ON the

main supply.

4. Move the pointer i.e. rotor position of synchro transmitter in steps of 300 and

observe the rotor position. Observe that whenever transmitter rotor is rotated, the

receiver rotor follows it for both the directions of rotations and their positions are

in good agreement.

5. Enter the input angular position and output angular position in the tabular form

and plot a graph.

3

CIRCUIT DIAGRAM:

Fig: 2.1. Synchro transmitter and receiver pair

4

THEORY:

TABULAR COLUMN:

Synchro Transmitter:

S.NO Rotor Position

in degrees

Vs3s1 Vs1s2 Vs2s3

0

30

60

.

.

.

.

.

.

330

Synchro transmitter & Receiver Pair:

S.NO Rotor position of

transmitter in degrees

Rotor position of receiver in

degrees

0

30

60

.

.

.

.

330

5

GRAPHS:

SYNCHRO TRANSMITTER

Fig: 2. 2.

SYNCHRO TRANSMITTER RECEIVER PAIR

Fig: 2.3

RESULT:

COLCLUSION:

6

Rec

eive

r an

gula

r po

siti

on

Transmitter angular position

Sta

tor

indu

ced

line

vo

ltag

e

V

θ

Vs1s3 Vs3s2 Vs2s1 Vs1s3

EXPERIMENT - 3

EFFECT OF FEEDBACK ON DC SERVO MOTOR

AIM :

To study DC position control with and without feedback.

APPARATUS:

DC Position control trainer kit.

CIRCUIT DIAGRAM:

Fig: 3.1. DC Position Control System

THEORY:

PROCEDURE:

1. The switches SW3 , SW4 are initially OFF and are ON as soon as the power

supply is ON.

e a

J2M

7

Am

pli

fier

5 V

2. Keeping the SW1 switch open adjust the input to different values and note down

the corresponding output and the deviation.

3. Now keeping the SW1 ON note down the output for different values of input in

both degenerative and regenerative modes and also the deviation.

TABULAR COLUMN:

1. TACHO OUT:

S.NO INPUT OUTPUT DEVIATION

2. TACHO DEGENERATIVE:


8

3. TACHO IN (REGENERATIVE):


GRAPHS:

Fig: 3.2. Tacho Out Fig: 3.3 Tacho IN (Regenerative)

Fig: 3.4 Tacho IN ( Degenerative)

RESULT:

CONCLUSION:

9

PositionPosition

Position

Dev

iati

on

Out

put

Dev

iati

on

EXPERIMENT - 4

EFFECT OF P, PD, PI, PID CONTROLLER ON A SECOND ORDER SYSTEM

AIM:

To study the effect of proportional, integral, differential, controllers on a second

order system.

APPARATUS:

1. Microprocessor based PID controller trainer kit.

2. Patch chords

CIRCUIT DIAGRAM:

Fig: 4.1. Effect of PID on second order system

THEORY:

PROCEDURE:

PROPORTIONAL CONTROLLER

1. Select DC source set the amplitude of a dc source to some predefined value.

2. Connect the PID output to time constant – 1 input, connect time constant -1

output to feed back input –VF. Set the PID parameter P-20.00, I and D = 0. Now

start the PID controller. It shows run. Note down Vs, VF , Error and PID output.

3. Repeat this for different values of proportional gain and tabulate the result.

10

PID Controller Second OrderSystem

Verr VPID

OutputVs

PROPORTIONAL INTEGRAL CONTROLLER

1. Select DC source set the amplitude of DC source to some value.

2. Connect DC source to set input Vs connect PID output to time constant – 1 input,

time constant – 1 output to feed back input – VF

3. Set P – to some value, ‘I’ to some value and‘d’ to zero now start the controller.

Note down Vs, VF, Verr and PID output voltages. Repeat this for different values of

P and I, gain and tabulate then readings.

PROPORTIONAL DERIVATIVE CONTROLLER

1. Repeat the above with P and D gain settings keeping I gain at 0.

2. Tabulate the readings of Vs, VF and Verr and PID output.

PROPORTIONAL INTEGRAL DERIVATIVE CONTROLLER

1. Repeat the above process for different P, D and I gains.

TABULAR COLUMN:

P – CONTROLLER

S.NO P - Gain Set voltage

Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

I - CONTROLLER

11


Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

D - CONTROLLER


Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

PI - CONTROLLER


Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

PD - CONTROLLER

12


Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

PID - CONTROLLER


Vs

Feed back

voltage VF

Error

Voltage

PID o/p Vo

RESULT:

COLCLUSION:

EXPERIMENT - 5

13

STATE SPACE MODEL FOR CLASSICAL TRANSFER FUNCTION USING

MATLAB

AIM: To write a program using MATLAB to transform a transfer function into state

space and vice versa

PROGRAM:

a= input (‘enter “1” for tf to to ss conversion and “2” for ss to tf conversion’);

If a= =1

num=input(‘enter the numerator of tf’);

den= input(‘enter the denominator of tf’);

[A,B,C,D] = tf 2 ss (num,den);

A,B,C,D

End

If a= =2

A=input(‘enter the system matrix’);

B=input(‘enter the input matrix’);

C=input(‘enter the output matrix’);

D=input(‘enter the transmission matrix’);

[num,den]=ss2tf(A,B,C,D);

Num,den

end

y=tf(num,den)

RESULT:

CONCLUSION:

EXPERIMENT - 6

14

LAG AND LEAD COMPENSATION – MAGNITUDE AND PHASE PLOT

AIM:

1. To Study lead compensation.

2. To study lag compensation.

3. To study lead lag compensation.

APPARATUS:

1. Trainer kit.

2. Function generator.

3. Connecting wires.

CIRCUIT DIAGRAM:

1. LAG NETWORK:

Fig: 5.1.

2. LEAD NETWORK:

15

Fig : 5.2.

3. LIMITED LAG NETWORK

Fig: 5.3.

4. LIMITED LEAD NETWORK:

16

Fig: 5.4.

5. LAG LEAD COMPENSATION NETWORK

Fig: 5.5.

17

THEORY:

PROCEDURE:

1. Circuit is to be connected as per the circuit diagram.

2. Give a sinusoidal function as input using a function generator with an amplitude

of 3V.

3. Select various frequencies and give as input to the lag, lead and lag lead

compensating networks.

4. Note the phase angle from the phase angle meter and tabulate the input and output

voltages for different frequencies.

5. Calculate the phase angle theoretically and verify with the indicated value.

6. Draw the frequency and phase plots.

TABULAR COLUMN:

1. LEAD NETWORK

S.NO Freq(Hz) ω=2Пf V0(V) Vi(V) Gain

A(dB)

Indicated

T(j ω)θ

Calculated

T(j ω)θ

18

2. LAG NETWORK


A(dB)

Indicated

T(j ω)θ

Calculated

T(j ω)θ

3. LIMITED LAG NETWORK


A(dB)

Indicated

T(j ω)θ

Calculated

T(j ω)θ

19

4. LIMITED LEAD NETWORK


A(dB)

Indicated

T(j ω)θ

Calculated

T(j ω)θ

5. LAG LEAD NETWORK


A(dB)

Indicated

T(j ω)θ

Calculated

T(j ω)θ

20

GRAPHS:

1. Lag network

2. Lead network

3. Limited lag network

4. Limited lead network

5. Lag lead network

RESULT:

CONCLUSION:

21

EXPERIMENT - 7

TRANSFER FUNCTION OF A DC GENERATOR

AIM: To determine the transfer function of a DC generator after determining the various

constants

APPARATUS:

1. D.C. Motor-Generator set.

2. Motor stator.

3. Field rheostat for Motor.

4. Rheostat as potential divider for excitation of generator.

5. Ammeter M.C,M.I

6. Voltmeter M.C,M.I

7. Tachometer.

8. Variac and connecting wires.

THEORY

PROCEDURE:

1. Make the connections as per the circuit diagram, keep the motor field rheostat

in minimum position and potential divider also kept in minimum potential

position.

2. Start the motor with the help of motor starter and adjust the speed to rated

value.

3. To determine Kg ,magnetization characteristics If vs Vg of separately excited

DC generator has to be found use the straight line portion to determine

Kg =Vg / If

22

4. The field resistance of generator Rf is determined by drop test method as

shown in fig 6.2

5. To find Lf of generator, first the impedance Zf is determined by voltmeter and

ammeter method as shown in fig 6.3 using A.C. supply and determines X f and

Lf.

6. Plot the magnetization characteristics between Generated voltage vs Field

current

CIRCUIT DIAGRAM:

Fig: 6.1. O.C.C of a DC Generator

z

zz

z

zz

M G

23

Fig: 6.2. Field resistance Drop Test

Fig: 6.3. Field Impedance Drop Test

24

TABULAR COLUMN:

1) Magnetization Characteristic :

S.No. Field current If(Amps) Generated voltage (Volts)

2)Field Resistance Rf:

S.No. V(volts) I(amps) Rf=V/I

25

3)Field Impedance:

S.No. V I Z=V/I

CALCULATIONS:

Field Resistance Rf = 1.2*Rfavg

Xf = (Zf2 - Rf

2 )0.5

Field Inductance Lf = Xf / (2*П*f)

To calculate the Kg ,The linear portion of the magnetizing characteristics is

required Kg=Vg/If

Therefore, The Transfer Function of a DC Generator is given by

Vg(s) /Vf(s) = Kg / ( Lf S+Rf)

26

MODEL GRAPH:

Field Current If

RESULT:

CONCLUSION:

27

Gen

erat

ed V

olta

ge E

g

EXPERIMENT - 8

TEMPERATURE CONTROLLER USING PID

AIM:

To study the phenomenon of steady state error of a temperature control system

using proportional controller, proportional integral controller and proportional differential

controller.

APPARATUS:

1. Trainer kit

2. Connecting wires

CIRCUIT DIAGRAM

Fig: 7.1 . Proportional Controller

θ

28

Fig: 7.2. Proportional Integral Controller

Fig:7.3. Proportional Derivative Controller

θ

θ

29

THEORY:

PROCEDURE:

1. Establish the connection between the conditions unit and the model process with

the help of cable provided.

2. Connect Red 3, Black 1 for P – controller, Red 3, Black 2, and Red 1, Black 1 for

PI controller, RED 3, Black 3 and Red 2 , Black 1 for PD controller with the help

of patch chords.

3. Set the ‘SET’ potentiometer at position of 16Ω corresponding to 400 of

temperature.

4. Set proportional band control to 10% i.e. K1 = 10

5. Now turn ON the power supply.

TABULAR COLUMN:

P CONTROLLER

S.NO LOW SPEED DEVIATION HIGH SPEED

DEVIATION

30

PI CONTROLLER


DEVIATION

PD CONTROLLER


DEVIATION

31

GRAPHS:

Fig:7.4. P – Controller Fig: 7.5. PI - Controller

Fig: 7.6. PD - Controller

RESULT:

CONCLUSION:

32

Low Speed

High SpeedTime(sec)

Dev

iati

on

Low Speed

High Speed

Time (Sec)

Dev

iati

onHigh Speed

Low Speed

Time (Sec)

Dev

iati

on

EXPERIMENT - 9

CHARACTERISTICS OF MAGNETIC AMPLIFIERS

AIM:

1. To study series connected magnetic amplifier.

2. To study parallel connected magnetic amplifier.

3. to study saturated magnetic amplifier.

APPARATUS:

1. Magnetic amplifier trainer kit.

2. Latches.

CIRCUIT DIAGRAM:

1. SERIES CONNECTED

Fig 8.1. Series connected magnetic amplifier

A1

B1

33

2. PARALLEL CONNECTED

Fig 8.2. Parallel connected magnetic amplifier

34

3. SATURATED MAGNETIC AMPLIFIER

Fig 8.3.Self saturated magnetic amplifier

THEORY:

PROCEDURE:

SERIES CONNECTED MAGNETIC AMPLIFIER

The complete circuit diagram for conducting this experiment is built in the unit itself.

1. Keep slide switch in position ‘0’ which will be indicated by an indicator, after the

unit is switched ON.

2. Keep control current setting knob at its extreme left position which ensures zero

control current at starting.

35

3. With the help of plug in links, connect following terminals on the front panel of

the unit.

a) Connect Ac to A1

b) Connect B1 to A2

c) Connect B2 to L

4. Connect 100W fluorescent lamp in the holder provided for this purpose and

switch ON the unit.

5. Now gradually increase control current by rotating control current setting knob

clockwise in steps and note down control current and corresponding load current.

6. Plot the graph of load current Vs control current.

PARALLEL CONNECTED MAGNETIC AMPLIFIER

The procedure is same as for series connected magnetic amplifier but connections of

the terminals on the front panel of the unit are made as follows:

a) Connect Ac to A1

b) Connect A1 to A2

c) Connect B2 to L

d) Connect B1 to B2

SELF SATURATED AMPLIFIER

The procedure is same as explained above but switch is kept in position ‘E’ and the

terminals on the front panel of the unit are made as follows:

a) Connect Ac to C1

b) Connect A3 to B3

c) Connect B3 to L

36

TABULAR COLUMN

SERIES CONNECTED

S.NO Control Current IC(mA) Load Current IL(mA)

PARALLEL CONNECTED


SATURATED MAGNETIC AMPLIFIER


37

GRAPHS:

Fig: 8.4. Series Connected magnetic amplifier Fig: 8.5. Parallel Connected

Magnetic amplifier

Fig: 8.6.Saturated Magnetic amplifier

RESULT:

CONCLUSION:

Control Current Control Current

Control Current

38

Loa

d C

urre

nt

Loa

d C

urre

nt

Loa

d C

urre

nt

EXPERIMENT - 10

CHARACTERISTICS OF AC SERVOMOTOR

AIM:

To study the speed torque characteristics of AC servomotor.

APPARATUS:

1. Trainer kit

2. Multimeter

3. Connecting wires.

CIRCUIT DIAGRAM:

Fig: 9.1.AC Servomotor

Servo Amplifier

V

39

THEORY:

PROCEDURE:

1. Study all the controls carefully on the front panel.

2. Initially keep the load switch at OFF position, indicating that the armature circuit

of DC machine is not connected to auxiliary DC supply 12V dc. Keep servomotor

supply switch also at OFF position.

3. Ensure load potentiometer and control voltage autotransformer at minimum

position.

4. Now switch on main supply to the unit and also AC servomotor supply switch.

Vary the control voltage transformer. You can observe that the AC servomotor

will be indicated by the tachometer in the panel.

5. With load switch in OFF position, vary the speed of AC servomotor by moving

the control voltage and note down back emf generated by the DC machine(Now

working as a generator or tacho), Enter the results in the table.

6. Now with load switch at OFF position, switch ON AC servomotor and keep the

speed in the minimum position. You can observe that the AC servomotor starts

moving with speed being indicated by the tachometer. Now vary the control

winding voltage by varying the autotransformer and set the speed for maximum

speed. Now switch on the load switch and start loading AC servomotor by

varying the load potentiometer slowly. Note down the corresponding values of Ia

and speed-readings are entered. The control voltage is also noted.

40

TABULAR COLUMN:

No load Torque T=0, Ia = 0

S.NO VC(Volts) Eb (Volts) Speed ‘N’ rpm

VC = 150V

S.NO Eb(Volts) N(rpm) Ia(Amps) P = EbIa(Watts) Torque(Nm)

41

VC=220V


VC = 225V


42

GRAPHS:

Fig:9.2 Fig: 9.3.

Fig:9.4.

RESULT:

43

Tor

qu

e

Speed

X1/R1>X2/R2>X3/R3

x

y y

x

1

23

Sp

eed

Torque

Vc=225V

Vc=200V

Vc=175V

Vc=150V

Eb

Speed

CONCLUSION:

EXPERIMENT - 11

ROOT LOCUS, BODE PLOT FROM MATLAB

AIM: To analyze the stability of a system using a) Bode plot b)Root locus c)Nyquist plot

PROGRAM:

Using Bode plot:

num = input(‘enter the numerator of tf’);

den = input(‘enter the denominator of tf’);

sys= tf(num,den);

bode(sys);

[gm, pm, weg , wep]=margin(sys)

gmbd = 20 * log 10(gm)

if((pm>0)&(gmbd>0))

disp(‘the given system is stable’);

else

if((pm= =0)&(gmbd= =0))

disp(‘given system is marginally stable’);

else

disp(‘given system is unstable’);

end

end

Using Root locus:



sys= tf(num,den);

[r,k] = rlocus(sys);

44

rlocus(sys)

count=0

for i=1;length(k);

if real (r(i)>0)

count =count+1;

end

end

if count= =0

disp(‘system is stable’);

else

disp(‘system is unstable’);

end

Using Nyquist plot:



s= tf(num,den);

nyquist(num,den);

[gm,pm,def,pef]=margin(s)

if((gm>0)&(pm>0))

disp(‘system is stable’);

else

disp(‘system is unstable’);

end

OUTPUT:

CONCLUSION:

45

EXPERIMENT – 12

ON – OFF TEMPERATURE CONTROLLER

AIM: To study ON – OFF temperature Controller.

APPARATUS:

1. ON – OFF Temperature Controller Equipment

CIRCUIT DIAGRAM:

Fig: 12.1 Block Diagram of ON – OFF Temperature Controller

Heater

+ 12 V230 V

46

THEORY:

PROCEDURE:

1. Connect the RTO sensor PT – 100 to the binding post provided on the front panel.

2. Connect the heater cable on the rear side socket.

3. Keep rotary switch on the front panel in 00 degree position. And on the supply.

4. The D.P.M should indicate 0-0 degree centigrade.

5. When select switch is taken to 100 degree position DPM should indicate 100

degree centigrade. This completes calibration check and ensures that MIN and

MAX controls on the PCB are properly adjusted.

6. Keep the select switch in SET position and adjust SET TEMP.(p1)

pot to 560 c. Keep dead band pot to most counter clock wise position(MIN).

7. Take select switch to RTD position. Now you can observe that RTD temperature

goes on increasing and the controller keeps the temperature of the process around

the set point depending on dead band adjustment.

8. Take readings of the temperature at regular intervals of 10sec or 15sec and plot a

graph for temperature vs time readings.

9. You may adjust dead band to most clock wise position(MAX) and repeat the

process again.

10. If you keep a fan near process model, you may again take another set of readings

and observe oscillations in temperature.

47

TABULAR COLUMN:

Set temperature = 500

Minimum dead band:

S.NO. Time(Sec) Temperature(degrees)

Maximum dead band:

S.NO. Time(Sec) Temperature(degrees)

48

GRAPHS:

Fig: 12.2. Temperature Verses Time

RESULT:

CONCLUSION:

49

Time (sec) x

Tem

pera

ture

y

Documents

Cslab Expts New