To provide a distributed power system that determines the failure of an apparatus without being affected by fault of a commercial power system or load ripple and can stop it only in case that the apparatus has gone wrong.
A distributed power unit 103 includes a fault information storage means 108, which stores its fault class and its property value in every detection of fault, a network I/F 109, and a failure decision means 110. It determines that the apparatus is faulty, when the fault class upon failure of the distributed power unit 103 that the network I/F 109 receives, the time-serial occurrence pattern of property values, and the fault occurrence pattern that the fault information storage means 108 stores accord with one another, by the failure decision means 110.
MORI YASUHIRO
Hiroki Naito
Daisuke Nagano