A Hybrid Stepper Motor Control Solution Based on A Low-Cost Position Sensor

A position control solution for hybrid stepper motor is presented with a low-cost Magnetic Rotary Position Sensor. A harmonic compensation method based on linear regression algorithm is shown to improve the performance of the low-cost position sensor. A sensor fusion algorithm based on Extended Kalman Filter is evaluated to further eliminate the signal error. In the sensor fusion process, a position signal calculated from back-emf measurements is fused with position signal from the low-cost position sensor and the result is discussed on practical purpose. For the position control, the control strategy is based on vector control. PID controllers are involved in both current and position control loops. Additional speed and acceleration terms are taken into account to form the position controller. An experimental test are run with a motor trajectory from an industrial implementation in the end and positive results prove the feasibility of this low-cost solution.