A Study on the Harmonics Effect of Disc-Type Over Current Ground Relay for Emergency Generator Protection

비상발전기 보호용 원판형 지락과전류계전기의 고조파영향에 관한 연구

Kim, Kyung-Chul;Kho, Hun

  • Received : 2015.03.03
  • Accepted : 2015.03.20
  • Published : 2015.06.30


When an emergency generator is running, it supplies the power for critical loads. Generator protection requires the consideration of many abnormal conditions that may occur with generators include overvoltages and ground faults. Modern day power systems create harmonics within the electrical network that can have an impact upon the associated protective system. This paper focuses on the analysing of the cause and development of a solution for the malfunction of induction disc type overcurrent ground relay by generation of harmonics during emergency generator operation.


Emergency Generator;Overcurrent Ground Relay;Harmonics Effect


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Supported by : 홍익대학교