Experiment No. 3
Electrical Engineering (9039)
Experiment No. 3
1.0
TITLE :
To verify Maximum Power Transfer Theorem.
2.0
PRIOR CONCEPTS :
1.
2.
3.0
Internal resistance of source, load resistance.
Thevenin’s equivalent circuit and Norton’s equivalent circuit.
NEW CONCEPTS :
Proposition 1 : Statement of Maximum Power Transfer Theorem.
•
Maximum Power is transferred from source to load when load resistance is made equal to
internal resistance of the source.
The value of Power Transfer is given by
Pmax = IL2 RL Watt’s
Where IL = Load current and RL = Load resistance.
Concept Structure 1 :
Proposition 2 : Application of Maximum Power Transfer Theorem.
•
Maximum Power Transfer Theorem is applicable to analyze the circuit in different electrical
engineering fields.
•
It is widely useful to analyze the electronic and communication network. It is frequently
significant in the operation of transmission line and antenna. Its use in electrical Power
transmission and distribution system is limited.
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MAHARASHTRA STATE BOARD OF TECHNICAL EDUCATION
Electrical Engineering (9039)
Experiment No. 3
Concept Structure 2 :
4.0
LEARNING OBJECTIVES :
4.1
Intellectual Skills
1.
To apply Thevenin's or Norton's Theorem.
2.
To interpret the applications of maximum Power Transfer Theorem.
3.
To understand significance of load resistance.
4.2
Motor Skills
1.
Ability to make the connections as per the circuit diagram.
2.
Ability to very the load i.e. the load resistance.
5.0
CIRCUIT DIAGRAM :
6.0
EQUIPMENTS : (STUDENT TO WRITE THE RANGES IN THE SET UP)
1.
2.
3.
4.
Rheostats Ri(…….…....Ω …………….A), RL(…………...Ω …………….A)
Multimeter ………………………….1 No.
D.C. Ammeter ( 0-……………A)
D.C. Voltmeter ( 0-…………...V)
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Experiment No. 3
7.0
STEPWISE PROCEDURE :
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
8.0
Electrical Engineering (9039)
Make the connections as per the circuit diagram.
Adjust the value of Ri and RL such that Ri = RL
Confirm the value of Ri and RL by measuring with the help of the multimeter.
Switch ON the D.C. source of supply.
Note down the readings of ammeter and voltmeter as IL and VL into the observation table (at
the center as reading no.4)
Now vary the load resistance in one direction(towards its maximum value) and note the
readings of IL and VL
Repeat the procedure for 2 to 3 readings.
Now very the load resistance in other direction (towards its minimum value) and note the
readings of IL and VL
Switch OFF the supply and disconnect the circuit.
Plot the graph between load resistance RL (X- axis) and Power absorbed PL (Y- axis)
OBSERVATIONS :
Table for maximum Power Transfer Theorem.
9.0
CALCULATIONS :
1.
Load resistance
2.
Calculate the load resistance (RL) for each reading and tabulate the results.
Power absorbed by the load PL = IL2 RL (watt)
Calculate the Power absorbed by the load (PL) for each reading and tabulate the results.
10.0 CONCLUSION :
The Power absorbed by the load is maximum when load resistance (RL) is ………………… (less
than / equal to / greater than) the internal resistance of the source (Ri).
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MAHARASHTRA STATE BOARD OF TECHNICAL EDUCATION
Electrical Engineering (9039)
Experiment No. 3
GRAPH
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Experiment No. 3
Electrical Engineering (9039)
11.0 QUESTIONS :
Write answers to Q ………, Q ………,Q ………, Q ……… (Question numbers to be allotted by
the teacher)
1.
State the maximum Power Transfer Theorem.
2.
Under the condition of maximum Power Transfer, what will be the efficiency of the circuit?
3.
State two applications of maximum Power Transfer Theorem.
4.
Maximum Power transfer is not always possible. Give reason
5.
Why is Maximum Power Transfer Theorem mostly applicable for analyzing electronic and
communication network?
6.
State Thevenin's theorem as applicable to D.C. network, having more than two sources?
7.
State Norton's Theorem as applicable to D.C. network.
8.
What is the difference between Thevenin's Theorem and Norton's Theorem?
(Space for Answer)
Signature of Teacher
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MAHARASHTRA STATE BOARD OF TECHNICAL EDUCATION
Electrical Engineering (9039)
Experiment No. 3
(Space for answers)
Signature of Teacher
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