| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress a power loss with a low torque by enhancing an accuracy in computation of a positional angle θ, extending from the low torque (low current) to a high torque (high current). <P>SOLUTION: A sensorless motor controller includes a magnetic pole position estimating means 45, which presumes the position of a magnetic pole in the rotor of a motor by superposing high frequency currents idh<SP>*</SP>and iqh<SP>*</SP>on the motor, without using a sensor which detects the position of a magnetic pole in the motor 10 that has a rotor having saliency. The controller includes a high frequency current control means 33 which changes the magnitude of the high frequency currents, based on the magnitude of the torque or currents of the motor 10. The larger the magnitude of the torque or currents of the motor 10 is, the more the control means 33 increases the high frequency currents; and the smaller the magnitude of the torque or currents of the motor is, the more the control means 33 decreases the high frequency currents. The control means reads high frequency current value designating data by table access with the torque or currents of the motor as its address, and sets high frequency current values. <P>COPYRIGHT: (C)2010,JPO&INPIT |
