| 摘要 |
PURPOSE:To make execution of safe running possible even when power converting means are abnormal, by a simple construction wherein one motor is driven by the remaining power converting means in the case when abnormality is detected in one of power converting means in a plurality, or in a plurality but not all of them. CONSTITUTION:In the case when one of power elements of a three-phase inverter main circuit 18 fails, for instance, any one of pulse distribution circuits 20a, 20b and 20c detects this abnormality and outputs a power element abnormality signal to an abnormality detection circuit 22. Then, the abnormality detection circuit 22 outputs an inverter abnormality signal to a control means. As the result, a first inverter 5 is stopped and a power supply to a three-phase winding 24 is discontinued. Since a second inverter 6 is normal, on the other hand, a power is supplied to a three-phase winding 25, a rotating magnetic field is generated and an induction motor 3 is driven. According to this constitution, safe movement can be executed even when one inverter fails. |
