PROTECTOR OF SYSTEM INTERCONNECTION INVETER

摘要

PURPOSE: To provide a protector which prevents the occurrence of secondary fault in the other in the case that fault occurs on either the DC side or AC side of an inverter circuit, in a system interconnection inverter which links a solar battery to a commercial power line. CONSTITUTION: This protector is provided with a fault diagnosis part 56 where normal operation province in the relation between the output current i of an inverter circuit 3 and the current amplitude command value lamp of a control circuit 5 is stored. The fault diagnosis part 56 judges the fault by whether the detection value of the output current and the current amplitude command value are in normal operation province or not. When fault is judged, the main controller 53 sends out a gate block signal to a gate circuit 54 so as to stop the operation of the inverter circuit 3.