| 摘要 |
<P>PROBLEM TO BE SOLVED: To quickly step up a capacitor by limiting a current flowing in a switching element of an inverter to below an allowable current. <P>SOLUTION: When the capacitor C1, which is connected between the positive side DC bus bar P and the negative side DC bus bar N of the inverter or between the positive side DC bus bar P of the inverter and a neutral point O of an AC motor M, is stepped up by a DC power supply E1 connected between the negative side DC bus bar P of the inverter and the neutral point O of the AC motor M, at least one of the switching elements T4-T6 connected to the negative side bus bar N of the inverter is turned on. The switching element is turned off after forming a short circuit for short-circuiting the DC power supply E1 via a stator winding of the AC motor M. Step-up operation, which forms a charging circuit for charging the capacitor C1 from the DC power supply E1 via the stator winding of the AC motor M and diodes D1-D3 connected to the positive side DC bus bar P of the inverter, are repeatedly executed. Thus, a both end voltage is stepped up by charging the capacitor C1. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
