| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a size of a filter circuit in an active filter connected to a power supply and a load in parallel and generating a high frequency compensation current for canceling a high frequency generated by the load, and also reduce a cost of a CPU in a controller. <P>SOLUTION: The active filter uses a power converter 3 comprising: a plurality of single-phase inverters 41-43 for converting DC power from a DC power supply 6 into AC power, and connected to each other on the AC side in series. A controller implements a step control of an output voltage from the power converter 3 by the sum of voltages generated by a predetermined combination of the single-phase converters selected among a plurality of the single-phase inverters 41-43, is provided with hysteresis comparators 29-32, and controls the power converter 3 so as to cause an output current from the power converter 3 to follow the high frequency compensation current 24a for canceling the high frequency component generated by the load 2. <P>COPYRIGHT: (C)2009,JPO&INPIT |
