Difficulty: Easy
Correct Answer: Converts constant-voltage DC directly into variable-voltage DC
Explanation:
Introduction / Context:DC–DC converters, commonly called choppers, are ubiquitous in electric drives, renewable energy systems, and battery-powered electronics. Understanding their basic function is foundational before studying control strategies, device selection, and ripple management.
Given Data / Assumptions:
Concept / Approach:A chopper regulates the average output voltage by rapidly switching the input DC on and off, varying the duty cycle D = TON / T. The result is a variable DC level after suitable filtering, without requiring an intermediate AC conversion stage (for basic buck/boost/buck-boost topologies).
Step-by-Step Solution:
Consider a simple buck chopper: Vout(avg) ≈ D * Vin.By adjusting D from 0 to 1, the effective DC output varies from 0 to Vin.No intermediate AC line-frequency conversion is required; switching happens at kHz range.Verification / Alternative check:
Practical converters may include inductors and capacitors to reduce ripple, but the fundamental action remains direct DC-to-variable-DC conversion via switching.Why Other Options Are Wrong:
DC→AC→DC: That describes a different architecture (inverter plus rectifier), not a basic chopper.AC frequency conversion and AC→DC are unrelated to DC–DC choppers.DC→AC only is an inverter function, not a chopper.Common Pitfalls:
Confusing choppers with inverters or AC regulators; ignoring the role of duty cycle in setting the average output.Final Answer:
Converts constant-voltage DC directly into variable-voltage DC
Discussion & Comments