Self-tuning control of both current sensor offset and electrical parameter variations for PM motor

It is very important to identify the electrical parameters accurately for the servo system of PM motor, that keep the fine torque response and the fine speed response. Generally, the electrical parameters of PM motor are identified by using the motor voltage and motor current. However, current sensor often has the offset value. In this case, the servo system of PM motor has the torque ripple and can not be identified accurately the motor parameters. In order to overcome these problems, this paper proposes a new self-tuning control of both current sensor offset and electrical parameter variation for PM motor. In this paper, the experimental results and the numerical simulation results confirm that the proposed method well estimates each current sensor offset of U phase and V phase, the motor resistance R_a, the motor inductance L_a and the motor magnetic flux ¿_fa individually and accurately, and carries out the fine self-tuning for the current controller of PM motor servo system.