| 摘要 |
PROBLEM TO BE SOLVED: To realize a hybrid filter-type filter device which is small-sized and light in weight, has simple constitution, and is manufacturable at a lower cost. SOLUTION: The filter device 1 for removing harmonic currents, whose one end is connected to a power-receiving point P between a power system 2 and a load circuit 3, is provided with a tuned filter 11 and an active filter 12. The tuned filter 11 tunes with a harmonic current of a specified order, and its one end is connected to the receiving point P. The active filter 12 is connected directly to the other end of the tuned filter 11, suppresses harmonic currents contained in the power system current flowing on the side of the power system 2 with respect to the receiving point P, and generates an active filter output voltage for canceling the component of a voltage drop generated, when load-side harmonic currents of orders different from the specified order, out of harmonic currents contained in a load current flowing on the side of the load circuit 3, with respect to the receiving point P, flow in the tuned filter 11. |
