| 摘要 |
<P>PROBLEM TO BE SOLVED: To facilitate checking an open failure of a main circuit semiconductor device, and to facilitate detecting the breakage of a main circuit line prior to the start of a motor without driving an inverter device. <P>SOLUTION: High resistance resistors r1, r2 which are connected in series to each other and have different resistance values are connected between DC positive/negative bus bars P, N, and main circuit semiconductor devices T1 to T6 are connected to A-phase to C-phase arms. A motor M is connected to each arm. In such an inverter device, a voltage applied to the DC negative bus bar N can be measured at central points A1, B1 and C1 of the arms of the respective phases. The open failure of the main circuit element is determined by checking whether the DC bus bar is P or N with only one element brought into an on-state. Furthermore, as for the breakage of the main circuit line, the voltages of the central points A1, B1 and C1 are measured with one element brought into an off-state, and when the voltage of each central point of B1, C1 satisfies [r2/(r1+r2)×V], it is determined that there is no breakage at each phase of connecting points of the central points A1, B1 and C1. <P>COPYRIGHT: (C)2011,JPO&INPIT |
