| 摘要 |
PURPOSE: To realize the control of an inverter by both the ordinary operation during system interconnection and self-operation during system interruption by providing a first PLL circuit for generating an output current command value which has corrected the frequency fluctuation of an inverter output voltage at an individual operation after the occurrence of system interruption. CONSTITUTION: An output current command value arithmetic circuit 18 outputs an output current of an inverter 12 to a current control circuit 19 based on a system voltage detected from a transformer 26 during interconnection with a system power supply 16 and normally operates the inverter 12 in current control mode. To this output current command value arithmetic circuit 18, a first PLL circuit 28 is provided, which creates an output current command value which corrected frequency fluctuation of an inverter output voltage at the individual operation after the occurrence of system power interruption. On the other hand, at the time of the occurrence of system power interruption, the frequency fluctuation due to the individual operation of the inverter 12 is corrected by a self-advancing oscillated waves of the first PLL circuit 28 based on a detected signal output from an anomaly detection circuit 27 and outputs a stable output current command value to the current control circuit 19. |
