Concept:The Transformer Utilization Factor (TUF) measures how effectively the transformer's VA capacity is converted into DC power delivered to the load.
Formula:$$\text{TUF}_{\text{bridge}} = \frac{P_{\text{dc}}}{V_{\text{rms}} \cdot I_{\text{rms}}} = \frac{(2 I_m / \pi)^2 R_L}{(V_m / \sqrt{2}) \cdot (I_m / \sqrt{2})} = \frac{8}{\pi^2} \approx 0.812$$
Solution:- In a bridge rectifier, the secondary winding conducts alternating current symmetrically during both half-cycles, eliminating DC core saturation.
- Evaluating: \( \text{TUF} = \frac{8}{\pi^2} = \frac{8}{9.8696} \approx 0.812 = 81.2\% \).
Why other options are incorrect:- Option A: 0.287 is the TUF of a half-wave rectifier.
- Option B: 0.406 is the maximum power efficiency of a half-wave rectifier.
- Option D: 0.672 is the TUF of a center-tapped full-wave rectifier secondary.
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