Exercise: Power Electronics

Questions for: Power Electronics

In a series inverter supplying a load resistance R, the commutating elements L and C should be such that
A:
B:
C:
D:
Answer: B

Load should be under damped.

📖
📝
💎
👁ïļ
UJT can be used for
A:
firing an SCR
B:
turning off an SCR
C:
both firing and turning off an SCR
D:
none of the above
Answer: A

UJT relaxation oscillator is used to provide gate pulses to SCR for triggering.

📖
📝
💎
👁ïļ

Assertion (A): The gate current of an SCR is always in the form of pulses.

Reason (R): The gate losses, in pulse triggering, are low.

A:
Both A and R are correct and R is correct explanation of A
B:
Both A and R correct but R is not correct explanation of A
C:
A is correct but R is wrong
D:
A is wrong but R is correct
Answer: A

Gate current in the form of pulses is commonly used because gate losses are low.

📖
📝
💎
👁ïļ
If ton and toff are the turn on and turn off times of a thyristor, then
A:
ton and toff are almost equal
B:
ton >> toff
C:
toff >> ton
D:
ton is about twice toff
Answer: C

Turn on time is less than 3 Ξs while turn off time is between 10-300 Ξs.

📖
📝
💎
👁ïļ
The number of leads in a power semiconductor diode are
A:
2
B:
3
C:
4
D:
2 or 3
Answer: A

A diode has 2 leads irrespective of its rating.

📖
📝
💎
👁ïļ
Ad Slot (Above Pagination)
Quiz