Concept:The Transformer Utilization Factor (TUF) measures how effectively a transformer secondary winding delivers DC power to the load.
Formula:$$\text{TUF} = \frac{P_{\text{dc}}}{\text{Transformer VA Rating}}$$
Solution:- In a center-tapped transformer, each half of the secondary winding conducts only half the time.
- Taking both halves into account, the secondary \( \text{TUF} \) is:
- $$\text{TUF}_{\text{center-tapped}} \approx 0.693$$
Why other options are incorrect:- Option A: \( 0.287 \) is the \( \text{TUF} \) for a single-diode half-wave rectifier.
- Option B: \( 0.812 \) is the bridge rectifier \( \text{TUF} \) (and full-wave theoretical efficiency \( \eta \)).
- Option D: A \( \text{TUF} \) of \( 1.000 \) represents an ideal theoretical transformer with zero harmonic losses.
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