Chapter 5 · MCQ Read Mode

Power Electronics and Control

An open-loop control system is characterized by:

A closed-loop (feedback) control system is characterized by:

A key disadvantage of open-loop systems compared to closed-loop systems is:

The transfer function of a linear system is defined as:

For a closed-loop system with forward gain G(s) and feedback gain H(s) (negative feedback), the overall transfer function is:

A key element unique to closed-loop systems (not present in open-loop systems) is the:

The error signal in a closed-loop system is generated by:

Which type of system generally provides better rejection of external disturbances?

A washing machine operating on a fixed timer (with no sensing of cleanliness) is an example of:

The transfer function concept applies strictly to systems that are:

A first-order system's step response is characterized by:

A second-order system with damping ratio ζ<1 is described as:

Critically damped response (ζ=1) is characterized by:

Settling time in a control system's step response refers to:

A linear control system is stable if and only if:

A pole located exactly on the imaginary axis of the s-plane indicates:

The Root Locus technique is used to study how a system's closed-loop poles move as:

In a PID controller, the proportional (P) term primarily:

The integral (I) term in a PID controller primarily serves to:

The derivative (D) term in a PID controller primarily:

A Bode plot represents a system's frequency response as:

Gain margin is measured at the frequency where:

Phase margin is measured at the frequency where:

For a stable control system, gain margin and phase margin should be:

A Nyquist plot is constructed by plotting:

The Nyquist stability criterion determines closed-loop stability by:

A key advantage of the Nyquist criterion over the Bode plot method is that it can:

The critical point used in Nyquist stability analysis is located at:

If the Nyquist plot passes very close to the critical point (−1+j0), the system is:

Both Bode and Nyquist plots are fundamentally used to analyze control systems in the:

A power diode is best described as:

A thyristor (SCR), once triggered on via its gate, will:

A GTO (Gate Turn-Off thyristor) differs from a standard SCR in that it:

A TRIAC is essentially equivalent to:

An IGBT combines characteristics of which two device types?

Compared to IGBTs, power MOSFETs generally offer:

Switching loss in a power semiconductor device occurs primarily due to:

Conduction loss in a power semiconductor device is primarily determined by:

A snubber circuit is used to:

Freewheeling (flyback) diodes are specifically used to protect switching devices when:

A half-wave rectifier conducts during:

A full-wave rectifier, compared to a half-wave rectifier, provides:

Total Harmonic Distortion (THD) quantifies:

Active power factor correction (PFC) circuits function by:

Pulse Width Modulation (PWM) in inverter control primarily serves to:

A basic square-wave inverter, compared to a PWM inverter, generally produces:

In a buck (step-down) DC-DC converter, the average output voltage is given by:

In a boost (step-up) DC-DC converter, the average output voltage is given by:

The average output voltage of a DC-DC converter is primarily controlled by adjusting:

A buck-boost converter is distinguished by its ability to:

An offline (standby) UPS normally supplies the load from:

An online (double-conversion) UPS provides power to the load via:

A line-interactive UPS differs from a basic offline UPS mainly by adding:

A key advantage of HVDC transmission over long-distance AC transmission is:

A monopolar HVDC link is characterized by:

A bipolar HVDC link offers improved reliability because:

A back-to-back HVDC link is specifically used to:

The smoothing reactor in an HVDC system primarily functions to:

DC filters in an HVDC system are used to:

The most critical and costly component of an HVDC transmission link is generally the: