| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress torque vibration of position control in a zero speed region and to securely and speedily switch a system from zero speed control to usual operation. <P>SOLUTION: In a variable speed control device of a motor, a holding circuit 10 holds a rotor position detection signal of the motor by one control period when a speed control state of the motor is in a usual operation speed region. When the control state is in the zero speed region, a position signal before it is put in the zero speed region is continuously held. A position compensation amplifier 11 obtains a position compensation torque signal obtained by amplifying a deviation between the rotor position detection signal and a holding signal of the holding circuit by a fixed gain, and adds it to the output of a speed control amplifier 3. A low-pass filter 13 equalizes a position deflection signal and removes a vibration component. A load torque establishment determining part 14 discriminates that a load torque is established when fluctuation of the position deflection signal falls within "stability discrimination width" and continues for not less than prescribed "stability discrimination time". <P>COPYRIGHT: (C)2009,JPO&INPIT |
