| 摘要 |
PROBLEM TO BE SOLVED: To provide at a low price a system which is excellent in capability for high-speed detection, has a narrow undetectable region, and is capable of detecting service interruption of a system without being accompanied with large variation of effective power, etc., on a DC power source side, without lowering system efficiency. SOLUTION: This is a system interconnection inverter unit 7 provided with an inverter portion 4 which converts inputted DC power into AC power and outputs it, and a controlling means 3, 10, 11 which controls the input voltage of the inverter portion to a constant value. The inverter unit 7 is fitted with a service interruption judging means for a system 5, 6, 10 which detects the variation of the output voltage or output current of the inverter portion which is generated owing to control by the controlling means, when service interruption to the system 9 occurs, and judges whether or not service interruption to the system occurs. |
