Concept:In a multi-phase rectifier, the output ripple frequency equals the number of conduction pulses per AC line period (\( p \times f \)).
Formula:$$f_{\text{ripple}} = p \times f \quad (p = \text{number of phases for half-wave})$$
Solution:- In a single-phase half-wave rectifier (\( p = 1 \)), the output ripple frequency is \( f \).
- A three-phase half-wave rectifier uses three diodes that conduct sequentially across \( 120^\circ \) intervals.
- This produces three output pulses per line cycle, resulting in an output ripple frequency of \( 3f \).
Why other options are incorrect:- Option A: \( f \) is the ripple frequency of a single-phase half-wave rectifier.
- Option C: \( 6f \) is the ripple frequency of a three-phase full-wave bridge rectifier.
- Option D: \( 2f \) is the ripple frequency of a single-phase full-wave rectifier.
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