| 摘要 |
1. Apparatus for starting and controlling the speed of a direct current electric motor, speed control being produced after starting by means of a low-power varying means (8) for regulating the value of the excitation current in a field winding (7) in a separate excitation mode, characterised in that the motor (1) starts at a low torque level in a series excitation mode of the field winding (7), and then the excitation circuit is automatically switched into the separate mode as soon as the speed and the counter electromotive force of the motor reach predetermined values.
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