대규모 그리드 접지전극의 과도접지임피던스의 측정

초록

This paper presents the transient and conventional grounding impedance behaviors of large grid grounding system associated with the injection point of impulse current. The measurement methods consider two possible errors in the grounding-system impedances: (1) ground mutual resistance due to current flow through ground from the ground electrode to be measured to the current auxiliary, (2) ac mutual coupling between the current test lead and the potential test lead. The test circuit was set to reduce the error factors. The transient grounding impedance depends on the rise time and injection point of impulse current. It is effective that grounding conductor is connected to the center of the large grid grounding system.