Difficulty: Easy
Correct Answer: True
Explanation:
Introduction / Context:
Cycloconverters directly synthesize low-frequency waveforms from a higher-frequency AC source by phase-controlled switching, without an intermediate DC link. Understanding their inherent frequency limit is fundamental in drives and large low-speed machine applications.
Given Data / Assumptions:
Concept / Approach:
Classic cycloconverters are step-down frequency converters; they construct each output half-cycle from many appropriately phased segments of the input. Since they select portions of the existing input cycles, the output fundamental cannot exceed the supply frequency.
Step-by-Step Solution:
Input frequency = f_s.Cycloconverter output is assembled by gating segments of the input → output fundamental f_o is a submultiple of f_s.Therefore f_o ≤ f_s, typically f_o ≪ f_s in practice (e.g., 10–20 Hz from 50/60 Hz).
Verification / Alternative check:
Applications such as large synchronous motor drives use cycloconverters specifically for low frequencies; for higher frequencies, DC-link inverters are preferred.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
True
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