낙뢰 시 태양광발전소의 개별접지 및 통합접지에 따른 낙뢰 유도 과전압 비교 분석

초록

Photovoltaic Power Plant(PV Plant) facilities have been steadily growing not only in Korea but also in the world. As the demand for PV Plant installation is continuously increasing, damages to the PV Plant are also increasing due to the lightning induced overvoltage caused by the lightning stroke. In this paper, the maximum lightning induced overvoltages at the critical facility for the 100kW PV Plant, (such as connection panel, inverter and distribution panel) in lightning strikes are compared by grounding systems(Isolation Grounding/Common Grounding) with simulation utilizing CDEGS. Simulation results show that the maximum lightning induced overvoltage generated in the critical facility for 100kW PV Plant is approximately 68kV lower in common grounding than in isolation grounding when a lightning current is applied to a point closest to a critical facility. In case of lightning, this paper concludes that common grounding is safer than isolated grounding in order to protect the critical facility for 100kW PV Plant from lightning induced overvoltage.