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Why transformers connected in parallel should have same voltage ratio?

Why transformers connected in parallel should have same voltage ratio? Correct Answer To avoid no-load circulating current

The transformers must have the same voltage-ratio to avoid no-load circulating current when transformers are in parallel on both primary and secondary sides. Since the leakage impedance is low, even a small voltage difference can give rise to considerable no-load circulating current and extra I2R loss.

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Select the correct answer: