| 摘要 |
Voltage change rate detection units (2a, 2b) are provided that detect the change rates of the voltages between both ends of flying capacitors (C3, C4) which are provided for each phase and to which voltages different from those across capacitors (C1, C2) are charged. When the change rates of the voltages between both ends of the flying capacitors (C3, C4) exceed a threshold value, it is detected that a short circuit occurs. A short-circuit abnormality signal is then transmitted to a controller unit (6) of each phase, and a drive circuit (7) for each switching element interrupts a gate signal. This allows a protective treatment for a short-circuit failure to be performed with a simple configuration without increasing the communication speed between a shared controller and a controller within a phase module. |
