POWER ELECTRONICS QUIZ

A single phase one pulse controlled circuit has a resistance R and counter emf E load 400 sin(314 t) as the source voltage. For a load counter emf of 200 V, the range of firing angle control is

30° to 180°.

60° to 180°.

60° to 120°.

30° to 150°.

TRUE ANSWER : ?
YOUR ANSWER : ?

A power semiconductor may undergo damage due to

Low dv/dt.

Low di/dt.

High di/dt.

High dv/dt.

TRUE ANSWER : ?
YOUR ANSWER : ?

After proper turn on of thyristor

None of these

gate signal is always present.

gate signal must be removed.

gate signal should present but can be removed.

TRUE ANSWER : ?
YOUR ANSWER : ?

Which semiconductor device acts like a diode and two transistor?

Diac.

Triac.

SCR.

UJT.

TRUE ANSWER : ?
YOUR ANSWER : ?

If a latching current for the circuit shown in figure is 2 mA. Obtain the value of minimum width of the property turn ON the SCR?

3.2 µs

3.1 µs

3.3 µs

3 µs.

TRUE ANSWER : ?
YOUR ANSWER : ?

Snubber circuit is used with SCR

either series or parallel.

anti parallel.

in parallel.

in series.

TRUE ANSWER : ?
YOUR ANSWER : ?

COOLMOS device can be used in application up to power range of

100 KVA.

2 KVA.

500 VA.

1 KVA.

TRUE ANSWER : ?
YOUR ANSWER : ?

A GTO can be turned on by applying

Positive drain signal.

None of these.

Positive source signal.

Positive gate signal.

TRUE ANSWER : ?
YOUR ANSWER : ?

By which one of the following we can measure the reliability of a string?

Derating factor.

String efficient.

Reliability factor.

Factor of safety.

TRUE ANSWER : ?
YOUR ANSWER : ?

When the temperature increases, the inter-base resistance (RBB) of a UJT ___________.

Increases

Remains the same

Decreases

None of these

TRUE ANSWER : ?
YOUR ANSWER : ?

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