Two generators G1 and G2 are to be operated in parallel to deliver a total current of 60 A.
Generator one has a terminal voltage of 280 V on no load and 240 V when supplying 40 A current.
Similarly the second generator has a voltage of 300 V when on no load and 240 V when supplying of 50 A of current.
The output voltage of each generator will be
A. 240 V.
B. 238.2 V.
C. 271.7 V.
D. 256.4 V.
Answer: D
Share your understanding of this question with the correct explanation.
To determine the output voltage of each generator, we can use the concept of voltage regulation.
Voltage regulation is a measure of how much the output voltage of a generator changes from its no-load voltage to its full-load voltage. It is given by the formula:
Voltage regulation = (No-load voltage - Full-load voltage) / Full-load voltage
For Generator 1:
No-load voltage = 280 V
Full-load voltage = 240 V
Current = 40 A
Voltage regulation for Generator 1 = (280 V - 240 V) / 240 V = 40 / 240 = 0.1667
For Generator 2:
No-load voltage = 300 V
Full-load voltage = 240 V
Current = 50 A
Voltage regulation for Generator 2 = (300 V - 240 V) / 240 V = 60 / 240 = 0.25
Now, to calculate the output voltage of each generator when they are operated in parallel to deliver a total current of 60 A:
Generator 1 output voltage = No-load voltage - (Voltage regulation x Full-load voltage)
Generator 1 output voltage = 280 V - (0.1667 x 240 V) = 280 V - 40 V = 240 V
Generator 2 output voltage = No-load voltage - (Voltage regulation x Full-load voltage)
Generator 2 output voltage = 300 V - (0.25 x 240 V) = 300 V - 60 V = 240 V
Therefore, the output voltage of each generator will be 240 V.
Hence, the correct answer is A: 240 V.