| 摘要 |
PURPOSE:To enable parallel closing to be executed by making output voltage difference zero irrespective of load condition, by controlling output voltage and phase of an inverter prior to parallel closing in accordance with load condition of the inverter in on-load operation. CONSTITUTION:When an inverter 101 is in on-load operation and an inverter 102 is in non-load operation, the inverter 101's switch 22 becomes ON and a switch 22' becomes OFF. An output of a current detector 21 of the inverter 101 in this condition is impressed onto differential voltage detecting circuits 11 and 11' as an equally detected current value. These circuits 11 and 11' are provided with not only current detecting function but also current deviation detecting function, the control signal from these circuits controls phase through frequency control circuits 13 and 13' and also controls output voltage through voltage control circuits 14 and 14'. By using this mechanism, it is possible, irrespective of load condition of the inverter device, to execute parallel closing of the inverter at the time when the output voltage and the phase agree with each other most appropriately. |
