| 摘要 |
Apparatus for controlling the starting of a three-phase, salient pole, synchronous motor employs a signal representing slip frequency obtained from a power sensor connected to the motor supply. It requires no connection to the field coil or to other motor component. Since the signal can be obtained from a power sensor, the starting can be controlled from a location remote from the motor, for example at the motor control switchgear. A detector determines when the signal has decreased in frequency to a point representing a rotor speed where field excitation should be applied and it provides an output control signal. This control signal causes field excitation to be applied. In its broadest sense the apparatus may be used to indicate slip frequency remotely. |
