| 摘要 |
PROBLEM TO BE SOLVED: To prevent the interference of electronic devices or radio equipment to be caused by the higher harmonic current which arises from semiconductor switching elements, in a power converting structured with semiconductor switching elements. SOLUTION: The DC side negative pole of a power converting device 8 is connected to the casing of an induction motor 5 and the casing of the induction motor 5 to a grounding device 7 with electric wires 50, 60 respectively. The electric wire 50 between the DC side negative pole of a power converting device 8 and the casing of an induction motor 5 is wired by twisting it with an electric wire between the AC side output of the power converting device 8 and the induction motor 5. This structure assuredly returns the higher harmonic current which spills out of the electric wire between the AC side output of the power converting device 8 and the induction motor 5 or from the induction motor 5 to the power converting device 8. |
