| 摘要 |
Provided is technology for improving, in an active filter, impediment to suppression of a harmonic component of power current caused by arithmetic processing performed by a current controller. The current controller (5) performs processing of generating a three-phase voltage command value V* based on output of a difference current generation unit (3A). The current controller (5) achieves the above-mentioned processing, for example, by performing PI (proportional integral) control, so that a delay time ta occurs. If a deviation Ie is obtained from a command value Ic* and compensating current Ic, the time ta causes a difference between the compensating current Ic and the harmonic component, and becomes an impediment to suppression of the harmonic component of the power current Is. However, by the difference current generating unit (3A) obtaining the deviation Ie from the compensating current Ic and a value Ic*^ obtained by leading a phase of the command value Ic* by a phase corresponding to the time ta, the above-mentioned impediment is eliminated or reduced. |
