| 摘要 |
PURPOSE:To prevent the operating characteristics of an electric motor vehicle from decreasing by connecting each DC motor to a normal chopper in series with one another when any of choppers becomes defective. CONSTITUTION:The first main motor 4a is controlled by a chopper 7a and the second main motor 4b is controlled by a chopper 7b at the normal operation time. In case that the chopper 7a becomes defective, the chopper 7a is disconnected by switching open switches 9a, 9c, 9d and 9f to open sides, and a control is performed by the chopper 7b in the state that the first motor 4a is connected in series with the second motor 4b. In this manner, it can prevent the operating characteristics from decreasing. |
