Design and simulation of a sensorless permanent magnet synchronous motor drive with microprocessor-based PI controller and dedicated hardware EKF estimator

Abstract

In this study, we propose a digital hardware implementation of a speed controller for a sensorless permanent magnet synchronous motor (PMSM) drive. First, the extended Kalman filter (EKF) is used to estimate the rotor flux angle (FA) and rotor speed. The estimated rotor FA is sent back to the current loop for vector control and the estimated rotor speed is fed back into the speed loop for closed-loop speed control. A PI controller is utilized in the speed loop control process. Second, we propose the architecture of a simple microprocessor based on the register transfer level method and we design machine code for the PI controller based on the proposed simple microprocessor. Third, the current vector controller and the EKF algorithm are implemented in dedicated hardware and the finite state machine method is used to design the computational process. Fourth, the Very high speed IC Hardware Description Language (VHDL) is employed to describe the behaviors of the simple microprocessor, the current vector controller, and the EKF algorithm. Finally, a co-simulation study was performed using Simulink and Modelsim to evaluate the effectiveness and correctness of the proposed system, and we present some simulated cases.