Question

Questions from protective Relaying course

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What are the possible reasons of unbalanced current in differential protection for power transformer? a) (4) b) What is magnetizing inrush current of transformer? How does the (6) inrush current impact on the differential protection of transformer? What are the grounding modes in power system? a) b) In a neutral indirectly earthed system, what is the function of an r suppression o (Petersen coil)? What are the possible compensation modes of arc-suppression coil? (6) e Which compensation mode is widely applied in practice? Why?

Answer 1

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