Abstract:
PROBLEM TO BE SOLVED: To estimate detection precision of a magnetic pole position by saliency of an electric motor.SOLUTION: In an electric motor control device 100a, superposed voltage phase adjusting means 7 outputs a high-frequency voltage phase command value θvhon the basis of a high-frequency current vector Ih extracted by current extraction means 6 from a current vector I. Current control means 5 estimates a magnetic pole position on the basis of the high-frequency voltage phase command value θvh, and outputs a fundamental wave voltage vector V1. Superposed voltage phase shift means 8 adjusts the high-frequency voltage phase command value θvh, and outputs a high-frequency voltage phase command value θvhhaving been shifted. Voltage superposing means 9 superposes an alternating voltage on the fundamental wave voltage vector V1on the basis thereof, and outputs the result to voltage conversion means 3. Sensitivity arithmetic means 10 computes sensitivity for estimation of the magnetic pole position on the basis of the high frequency current vector Ih and the high-frequency voltage phase command value θvhhaving been shifted.