A novel sensorless vector control method based on variable structure sliding mode control for interior permanent magnet synchronous motor (IPMSM)

To solve the problems that sensorless vector control is difficult to implement and that the parameters of normal PI (proportional integral) control cannot be adjusted on-line in the conventional motor control, we propose a novel control method. Sections 2 and 3 of the full paper explain in some detail our novel control method. Its core consists of: (1) we design a variable structure sliding-mode speed controller and a variable structure sliding-mode current controller to replace the traditional speed PI controller and two current PI controllers; (2) we design the unscented Kalman filter (UKF) observer to estimate direct-axis current, quadrature-axis current, load torque, rotor position and speed simultaneously. Section 4 presents simulation results and their analysis. The simulation results, given in Figs. 3 through 5, and their analysis show preliminarily that: (1) the variable structure sliding-mode controllers designed by us can effectively regulate the rotational speed and the current of the IPMSM; (2) the UKF observer we designed can accurately estimate motor states and is robust against perturbation, exterior disturbance and measurement error.