Power Electronics Quiz

In a dc motor if the field coil gets opened, speed of the motor will?

• decrease

• increase

• none of these

• stop

Armature voltage of a dc motor can be controlled by means of?

• bridge rectifier circuit with fixed input

• AC to DC converters

• inverters

• cycloconverters

Which of the following does not cause permanent damage to the SCR?

• high rate of rise of current

• High current

• high rate of rise of voltage

• high temperature rise

Device used for current protection is?

• RC Network

• the fuse

• none of these

• snubber circuit

Surge current rating of the SCR?

• repetitive current with triangular wave

• non repetitive current with sine wave

• non repetitive current with rectangular wave

• repetitive current with sine wave

The objective of connecting resistance and capacitor across gate circuit is to protect the thyristor gate against?

• none of these

• noise signal

• dv/dt

• over voltage

Zero voltage and zero current switching helps in?

• minimizing the switching losses

• increasing the switching losses

• minimizing the component size

• increasing the component size

Metal Oxide varistor is used for protecting?

• anode circuit against over voltage

• anode circuit over currents

• gate circuit against over voltages

• gate circuit against over currents