| 摘要 |
PURPOSE: To regulate the phase current pulse by supplying signals indicating the turn-on angle and turn-off angle corresponding to a previously selected positional angle of rotor and regulating the turn on angle continuously until the winding current reaches an optimal level. CONSTITUTION: When a polyphase motor 10 is turned on/off for each winding phase thereof, signals indicating the turn-can angle θo and turn-off angle θp corresponding to a previously selected positional angle of rotor 12 are supplied. At least one actual motor current signal is compared with a target motor current signal and the angular position of the rotor 12 is determined at a moment of time when the actual motor current in a corresponding phase of the motor 10 reaches the target motor current. In order to minimize the difference between the determined angular position of the rotor 12 and a previously selected angular position of a rotor 14, the turn-on angle θo is regulated in response to the determined angular position of the rotor. According to the arrangement, the current pulse can be controlled over a wide speed range and the loss of output torque can be reduced. |
