Power Electronics MCQs (Part-4)

What is the primary function of a diode in a power electronics circuit?

A To amplify voltage
B To allow current flow in one direction
C To store energy
D To control frequency

Which of the following is a type of power semiconductor device used for switching?

A Capacitor
B Diode
C Triac
D Resistor

What is the primary function of an inverter in power electronics?

A To convert DC to AC
B To store energy
C To convert AC to DC
D To regulate voltage

What is the role of the gate driver in power electronics circuits?

A To regulate current
B To control the switching of semiconductor devices
C To filter high-frequency noise
D To measure voltage

In a power rectifier, which component is responsible for converting AC to DC?

A Capacitor
B Inductor
C Diode
D Transistor

What is the key advantage of using MOSFETs in power electronics?

A High power loss
B Fast switching speed
C High current capability
D High voltage drop

What is a DC-DC converter used for?

A To convert AC to DC
B To convert DC to AC
C To convert DC from one voltage level to another
D To reduce current

What is a key characteristic of an IGBT (Insulated Gate Bipolar Transistor)?

A It is a current-controlled device
B It combines the advantages of MOSFETs and BJTs
C It is used only for low-power applications
D It requires high voltage at the gate to operate

What is the main purpose of using a snubber circuit in a power electronics system?

A To increase efficiency
B To protect against voltage spikes
C To reduce power consumption
D To regulate current flow

In a DC motor drive, what is the function of a chopper?

A To convert DC to AC
B To regulate the voltage
C To control the speed of the motor
D To step down the AC voltage

What is the purpose of a capacitor in a power factor correction circuit?

A To reduce voltage fluctuations
B To store energy
C To improve the power factor
D To filter high-frequency noise

What is the main difference between a buck converter and a boost converter?

A Buck converters step up the voltage, and boost converters step down the voltage
B Buck converters step down the voltage, and boost converters step up the voltage
C Buck converters convert DC to AC, and boost converters convert AC to DC
D There is no difference

Which of the following is a key application of a cycloconverter?

A AC to DC conversion
B DC to DC conversion
C AC to AC frequency conversion
D Power factor correction

In power electronics, what is the main use of Pulse Width Modulation (PWM)?

A To regulate power
B To filter high-frequency noise
C To control the output voltage or current
D To increase switching losses

Which of the following is a characteristic of a power MOSFET?

A It is voltage-controlled
B It requires high input current
C It can only be used in low-power circuits
D It is a current-controlled device

In a rectifier circuit, what happens if the diode is forward biased?

A No current flows
B The diode blocks current
C The diode conducts current
D The diode stops working

What type of rectifier circuit is used to convert single-phase AC to DC with a smoother output?

A Half-wave rectifier
B Full-wave rectifier
C Bridge rectifier
D Cycloconverter

What is the function of a transformer in power electronics circuits?

A To convert AC to DC
B To regulate power
C To step up or step down AC voltage
D To filter high-frequency noise

What is the main advantage of using a Zener diode in power supplies?

A To store energy
B To provide a constant voltage
C To filter high-frequency noise
D To increase current flow

What is the primary purpose of a protection circuit in power electronics systems?

A To increase system efficiency
B To prevent component damage due to overcurrent or overvoltage
C To improve power factor
D To control switching speed