Question

A 1-\(\phi\), 230 V, 50 Hz transformer is operated at 230 V, 60 Hz. Then its

• A. Eddy current loss will remain same and Hysteresis loss will increase
• B. Eddy current loss will remain same and Hysteresis loss will decrease
• C. Eddy current loss will decrease and Hysteresis loss will remain same
• D. Eddy current loss will increase and Hysteresis loss will also increase

Hint:

Increasing frequency while keeping voltage constant reduces core flux, affecting both types of losses.

Answer 1

The Correct Option is B

Eddy current loss \( \propto f^2 \), and Hysteresis loss \( \propto f \)
But if voltage is constant and frequency increases, the core flux decreases due to reduced volt-seconds per cycle. Hence:
- Eddy current loss (∝ \( B^2 f^2 \)) remains nearly same
- Hysteresis loss (∝ \( B^{1.6} f \)) decreases due to reduced flux \( B \)