Distribution system protection device and substation equipment

摘要

PROBLEM TO BE SOLVED: To provide a distribution system protection apparatus capable of protecting a distribution system more completely.SOLUTION: The protection apparatus 3 includes: a breaker 10 interposed between the low pressure side of a three-phase transformer 5 and the high pressure side of a three-phase transformer 2; an enclosure 60 housing the breaker 10; and a zero-phase voltage detector 30 configured to detect a zero-phase voltage between the breaker 10 and the three-phase transformer 2 and housed in the enclosure 60.