Generator PHEP

Question 1

The voltage output of an AC generator is controlled by

Answer 1

Varying the DC exciter voltage

Question 2

The major difference between various voltage regulator systems is merely the method by which:

Answer 2

Field circuit resistance and current are controlled

Question 3

The voltage held by the vibrating type voltage regulator can be adjusted by

Answer 3

Varying the weight W and adjusting the tension of the DC solenoid spring

Question 4

All of the following statements concerning the rheostat type voltage regulator are true EXCEPT for:

Answer 4

The primary purpose of the exciter field rheostat is to adjust the generator output voltage

Question 5

Wide-range excitation control is sometimes provided for in voltage regulator arrangement for large generators using separately excited main exciters by using a:

Answer 5

Wheatstone bridge rheostat

Question 6

When the regulator control switch for the amplidyne voltage regulator is in the ON position the effect is to:

Answer 6

ALL OF THE ABOVE:
- reduce the exciter field current
- lower the exciter voltage
- decrease the field current and terminal voltage of the AC generator

Question 7

In order to provide for proper division of reactive current between AC generators operating in parallel, their voltage regulators incorporate a scheme called:

Answer 7

Cross-current compensation

Question 8

Of the following statements concerning synchronous condensers, which one is not true?

Answer 8

The excitation range is maintained less than that for AC generators to prevent loss of synchronism

Question 9

In the rheostat type voltage regulator, when the terminal voltage of the AC generator starts to fall, the action of the torque motor:

Answer 9

Short-circuits more of the high-resistance plates

Question 10

System stability can be maintained and a faster time-response to load changed obtained by using voltage regulators equipped with:

Answer 10

Both a feedback control system and an electronically controlled separate motor