Method and controller for estimating initial magnetic pole position of sensorless salient pole type brushless DC motor

摘要

PPROBLEM TO BE SOLVED: To estimate the initial magnetic pole position precisely. PSOLUTION: In the method for estimating the initial magnetic pole position of a sensorless salient pole brushless DC motor 10, an -axis voltage command value vSB/SBand a -axis voltage command value vSB/SBby high-frequency wave on the coordinates forming a static orthogonal coordinate system are given to the driver 11 of the motor 10, an AC current supplied to the motor 10 from the driver 11 is detected as the -axis current iSB/SBand -axis current iSB/SBon the coordinates, a current amplitude difference i between the amplitudes of the -axis current iSB/SBand -axis current iSB/SBis calculated, the -axis voltage command value vSB/SBand -axis voltage command value vSB/SBbeing output to the driver 11 are subject to feedback control to eliminate the current amplitude difference i, and the initial magnetic pole position is calculated after the current amplitude difference i is eliminated. PCOPYRIGHT: (C)2009,JPO&INPIT