| 摘要 |
PURPOSE: To stop a load in safety or make a switching to an auxiliary power supply system before all inverters are stopped by making a decision that a system has failed on condition that at least one of a plurality of inverters operating in parallel has failed or the output current from one inverter has exceeded a predetermined level. CONSTITUTION: Output signals 111-115 from individual current detectors are fed to AND circuits 911-915 and logical product of the inverted values of output signals 101-105 from individual failed current detectors is produced. When an individual current detector detects an output current from any one inverter exceeding a predetermined level, an OR gate 903 produces an output thus detecting the overcurrent at the time of inspection and failure. On the other hand, outputs 101-105 from individual failed current detectors are fed to an OR gate circuit 905 in order to detect failure of these inverters. With such constitution, the failure of system is detected surely and the load can be stopped in safety or a switching can be made to an auxiliary power supply system before all inverters are stopped. |
