Improving the accuracy of permanent magnet rotor position estimation for stepper motors using magnetic induction and harmonic rejection

Abstract

To improve the accuracy of permanent magnet (PM) rotor position estimation for a hybrid stepper motor (HSM), the authors propose a sensorless control design based on the back electromagnetic force (back-EMF) caused by magnetic induction and harmonic rejection via an orthogonal third-order phase-locked loop (PLL 3 rd) and an integral harmonic filter (IHF). The accuracy of estimation is analysed considering PM rotor position estimation errors. The harmonics of the back-EMF signal are eliminated by the IHF before entering the PLL 3 rd, which synchronises and decreases position estimation error. This technique is a simple, reliable, and effective method for implementing sensorless control of an HSM. An industrial test-bench was used to implement the proposed scheme. The experimental results are presented to validate the effectiveness of the proposed estimation method.

A BMO‐based MRPID controller with optimal control of speed in hybrid stepper motor

“…30 As a result, the value of speed error is computed, and the proposed controller controls the error value. The following speed error value is taken into account: a formula (22),…”

“…The suggested technique has the ability to precisely identify bearing problems and may be used to monitor the health of stepper motors. Ngoc et al, 22 proposed a sensor less design based on electromagnetic force (back‐EMF) due to magnetic induction and suppression of harmonics by means of a third‐order orthogonal phase‐locked loop and an integrated harmonic filter (IHF). The accuracy was examined by taking into account the PM rotor position estimation errors.…”