| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power converter capable of reducing a leakage current applied from an AC electric motor to the ground (earth). <P>SOLUTION: The leakage current is detected by a leakage current detector 26 and reversely amplified by a reverse amplification circuit 27, and then, the detected leakage current I<SB>R</SB>(x) is divided into a positive component and a negative component by a complimentary transistor pair 30 and is amplified by NPN- and PNP-type transistors 31, 32, and the amplified components are composited in a signal at a compositing point 34 to be output. The current output from the compositing point of the complimentary transistor pair is output as a current I<SB>Q</SB>for canceling the leakage current is output to a flow path for grounding the leakage current I<SB>R</SB>. Then, a predetermined bias voltage VB is applied to a base of each of the transistors constituting the complimentary transistor pair. <P>COPYRIGHT: (C)2009,JPO&INPIT |
