Patent ID: 9252682
Filing Date: 2016-02-02
CPC Classification: G01R,H02J,H02M,Y02E

Claim Text:
1. A grid-connected inverter apparatus comprising: an inverter configured to convert a DC output based on power generated from a power generation equipment into an AC; a DC voltage measuring unit configured to measure a DC voltage on a DC input side of the inverter; a grid interconnection switch having two independent relay switches each corresponding to phases of a grid power system to which the inverter is connected; and a control unit configured to control the two relay switches, wherein the control unit, after opening the two relay switches, carries out changing control to one of the relay switches such that the opening control is changes to closing control and, based on a change in the DC voltage measured by the DC voltage measuring unit before and after the changing control, determines whether the other relay switch is faulty.