| 摘要 |
<P>PROBLEM TO BE SOLVED: To lower voltage in a compensation circuit, reduce the cross-sectional area of a magnetic core, and compensate for only a leakage current component flowing into the ground independently on power supply side and load side of an inverter. <P>SOLUTION: This noise reducer for the power converter is provided with a transformer 9 for detecting the ground leakage current, a compensation transformer 14, a current-detecting section 11, a compensation computing section 12, and a current-generating section 13. The transformer 9 for detecting the ground leakage current is formed from a winding 4 from an inverter 3 to a load motor 5 and a ground cable 7 connecting between ground terminals which are interlinked with the same magnetic body by the same number of turns, and is provided with a secondary winding 10 for detection. The compensation transformer 14 is formed out of the winding and the ground cable which are interlinked with the same magnetic body by the same number of turns and is provided with a secondary winding for compensation. The current-detecting section 11 detects the ground leakage current with the detection secondary winding for detection. The compensation computing section 12 gain multiplies the detected output of the current-detecting section and outputs a compensation current command for reducing the ground leakage current to zero. The current-generating section 13 supplies a current, corresponding to the compensation current command outputted from the compensation computing section to the compensation secondary winding. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
