| 摘要 |
PURPOSE:To suppress an abrupt overvoltage due to the trouble of a power converter and to protect the converter by interruption by providing a second energy absorbing element and an overvoltage detector at the output terminals of a rectifier provided at an AC side. CONSTITUTION:Power from a power source 15 is rectified by a power converter 1, and supplied to a DC motor DCM. A rectifier 2 is connected to the AC terminal of the converter 1, and a second energy absorbing element 4 and an overvoltage detector 5 are connected to the output of the rectifier 2. Further, the output terminal of the rectifier 2 is connected to the output terminal of the converter 1 through a diode. A predetermined voltage is charged in the element 4 by a charger 11. The element 3 absorbs a current at the time of a trouble to raise its voltage, and if it exceeds a specified value, the current is absorbed to the element 4. Thus, when the voltage rises, the converter 1 is interrupted by the operation of the detector 5. |
