A Novel Method to Suppress the Force Ripple of a Switched Reluctance Linear Motor

A novel method to suppress the force ripple of switched reluctance linear motors (SRLMs) based on predictive-fuzzy control is proposed in this article. Generally, the force ripple mainly occurs in the commutation area, resulting from the dropping force of the outgoing phase that cannot match the rising force of the incoming phase. The force distribution function (FDF) is a suitable method for controlling the forces of the outgoing phase and incoming forces during the commutation area. However, the controller calculation takes time and the motor shows inductive behavior, so the control signal, which is the reference current in FDF, always lags the reference force, which weakens the effect of the FDF control. Considering this problem, a method of predictive-fuzzy control is proposed in this article. The current can be controlled in advance by predicting the force, which reduces the appearance of the negative electromagnetic force, which is beneficial to improving the efficiency of the motor, and the mutual inductance is also considered in the predictive model. Additionally, a fuzzy controller is employed, and adaptive parameters of the control system are adopted. To validate the proposed control system, experimental verification is performed on a 500 W 6/4 double-sided SRLM, showing that the proposed method has a better force ripple suppression performance than the FDF control.