Electrical Engg (EEE) - MCQ Practice Questions

Which of the following devices is a unidirectional switch in power electronics?

The switching frequency of a PWM inverter is 10 kHz. What is the fundamental frequency of the output if the modulation index is 0.8?

In a half-bridge inverter, what is the minimum number of switches required to generate AC output from DC source?

Which modulation technique provides the best harmonic performance in high-power applications?

What is the primary purpose of a freewheeling diode in a buck converter?

In a three-phase full-bridge inverter, the total number of thyristors required is:

What is the conduction angle of each thyristor in a three-phase full converter operating at 60° firing angle?

The turn-off time of an IGBT at 25°C is typically in the range of:

In a forward converter, the energy stored in the magnetizing inductance during the ON time is transferred to:

What is the typical efficiency range of modern power MOSFETs in switching applications?

In a buck-boost converter, the polarity of output voltage compared to input is:

The dv/dt rating of a thyristor is critical because:

In a resonant DC-DC converter, what is the primary advantage over PWM converters?

The average output voltage of a three-phase half-wave uncontrolled rectifier is:

Which of the following is NOT a source of harmonic distortion in power converters?

In a synchronous rectifier design, the gate drive signal for the MOSFET switch should be synchronized with:

What is the maximum theoretical efficiency of a step-down chopper with duty cycle 0.5?

The phenomenon of 'latch-up' in power semiconductor devices occurs due to:

In soft-switching topologies, Zero Current Switching (ZCS) means switching occurs when:

In a three-phase fully controlled bridge rectifier operating at 50 Hz with a firing angle of 60°, what is the average output voltage if the RMS line-to-line voltage is 415V?