전원접지공급방식에 따라 배전용 변압기 2차측으로 이행되는 뇌서지

초록

The importance of improving the quality of electric power is strongly raised, owing to an increasing use of the sensitive and small-sized electronic devices and systems. The transient overvoltages on low-voltage power distribution systems are induced by direct or indirect lightning return strokes, and they can cause damage and/or malfunction of the electronic systems for home automation, office automation and factory automation as well as medical equipments. The behaviors of lightning overvoltages transferred to the secondary side of distribution transformer according to types of system grounding using a combination type impulse voltage and current generator were experimentally investigated. The TN system in protecting electronic circuits and system from lightning overvoltages entering through ac power lines are more effective than the IT and TT system.