| 摘要 |
<P>PROBLEM TO BE SOLVED: To converge fluctuations in output voltage and output current due to disturbance in a short time in a distributed power supply system in individual operation mode. <P>SOLUTION: Multiple current determination circuits 30u to 30w are provided which individually detect the output current values Iu, Iv, Iw of the respective phases in three-phase alternating-current power output from an inverter 8 to a load 5. When the detected output current value of each phase exceeds a current limit value Im, the current determination circuits respectively output gate block signals Gbu to Gbw. A PWM signal for a switching element 12 of each phase in the inverter is interrupted by a gate block signal of the corresponding phase. In this case, the following operation is performed when the output current value of each phase exceeds the current limit value and a gate block signal is output: the gate block signal is kept output until the leading edge of each pulse of a PWM synchronization signal occurs when a certain time has passed after the signal was output. <P>COPYRIGHT: (C)2009,JPO&INPIT |
