| 摘要 |
PROBLEM TO BE SOLVED: To suppress noise to the outside to minimum with a path in which high frequency current flows, simplify a structure and facilitate assembly, by disposing a switching element, a DC capacitor, and an AC filter capacitor in an integral unit so as to form the shortest wiring. SOLUTION: The anode terminals 4 and the cathode terminals 5 of the switching elements S1, S2 of a semiconductor switching unit are connected in parallel to DC capacitors 1, 2, and an AC filter capacitor 3 is connected to the serially-connected part of the DC capacitors 1, 2. By connecting wiring between a high frequency reactor 11 and the unit by the identical bundle, and connecting it to the AC filter capacitor 3 in the unit using the shortest wiring, AC current I4 becomes current with a high frequency component removed, so that high frequency noise to the outside is decreased largely. It is thus possible to close the high frequency noise in the unit, which is effective to reduce radiation noise. |
