When a given transformer is run at its rated voltage but reduced frequency, its____________?
Correct answer: D. core flux density is increased
- A. flux density remains unaffected
- B. iron losses are reduced
- C. core flux density is reduced
- D. core flux density is increased
Explanation
Transformer flux is approximately proportional to voltage divided by frequency. Keeping voltage rated while reducing frequency increases V/f, so the core flux and flux density increase, possibly causing saturation.
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