| 摘要 |
<P>PROBLEM TO BE SOLVED: To make it possible to recognize the presence or absence of a failure with system interconnection disconnected. <P>SOLUTION: A power conditioner device 4 includes: an inverter circuit 14 that has multiple switching arms 21, 22 each constructed of pair of switching elements and converts direct-current power from a dispersed power system 2 into the alternating-current power of a commercial system 3; a drive control circuit 18 for controlling driving of the switching elements; and an interconnection relay circuit 16 that disconnects system interconnection. The power conditioner device is provided with a voltage drop determination unit 32 and a control circuit 40. When a first diagnosis activation signal is detected, all the switching elements are turned off with the system interconnection disconnected. Thereafter, only one of the switching elements in off state is turned on and this switch-on operation is sequentially performed. The voltage drop determination unit determines whether or not the input voltage of the inverter circuit has dropped each time this switch-on operation is performed. When the voltage drop determination unit determines that the input voltage has dropped, the control circuit causes a display unit 17 to display a warning about short circuit failure. <P>COPYRIGHT: (C)2008,JPO&INPIT |
