This article elaborates a 66 kV capacitor bank breakdown and damage.Through disassembling the capacitor and combining with the fault wave chart

condition of the outer fuse and the protection setting value

the fault causes are analyzed carefully and concluded that breakdown happened during operation due to some defects existed during manufacturing.Meanwhile

the outer fuse could not burning off in time and the protection setting value was not correct are the other two important factors of such fault

which resulted in fault expansion.Aiming to the problems in such fault

some measures and suggestions are given through aspects such as type and connection mode of the capacitor

type of the fuse and protection setting.It has certain reference to the capacitors safe operation.