Method and device for injecting high frequency current vector

Abstract

A method and a device inject a high frequency current vector which has a fixed angle with the measured current vector flowing in the machine. The method: measures the motor current vector, determines a projection value of the motor current on an axis that is orthogonal to a direction having the fixed angle with the measured current vector, demodulates the high frequency variations of the projection value using a first high frequency demodulation signal, determines at least a first angle from the demodulated high frequency variation, determines the injection voltage vector at least from the first angle, a predetermined voltage and a second high frequency modulating signal, the second high frequency modulating signal having the same frequency as the first high frequency demodulating signal and a phase difference with the first high frequency demodulating signal that is equal to π/2.

Dependencies are inferred from the claim text.