AC Power Control MCQs

Practice AC Power Control MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.

Question 1

Power ElectronicsAC Power Control

Integral-cycle control regulates AC power by applying?

AComplete supply cycles to the load for some intervals and blocking complete cycles for others
BOnly one microsecond pulse per year
CA continuously variable DC voltage
DA different transformer turns ratio every half-cycle

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Correct Answer: A. Complete supply cycles to the load for some intervals and blocking complete cycles for others

Explanation: Integral-cycle or on-off control passes whole AC cycles during ON intervals and suppresses whole cycles during OFF intervals.

Reference: Standard power electronics: ac power control

Question 2

Power ElectronicsAC Power Control

Integral-cycle control is particularly suitable for loads with relatively large thermal time constants, such as?

AElectric heaters
BHigh-frequency RF mixers
CSmall-signal microphone preamplifiers
DCrystal oscillators

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Correct Answer: A. Electric heaters

Explanation: Thermal loads respond slowly, so groups of complete AC cycles can regulate average heating power without requiring rapid output response.

Reference: Standard power electronics: ac power control