An Iterative Estimation Algorithm of Prepositioning Focusing on the Detent Force in the Permanent Magnet Linear Synchronous Motor System

Abstract

In the process of prepositioning, the detent force of linear motor produces large difference between the given position and the actual position. It may also result in multipossible equilibrium points with indistinguishable distance. This article conducts research on an iterative estimation algorithm, which is verified on a surface permanent magnet linear synchronous motor (PMLSM). The iteration estimation algorithm focuses on the influence of the detent force on the initial position estimation of a linear motor. It also scales the effects of the detent force quantitatively. As for the balance between the detent force and electromagnetic force, the initial position of the PMLSM is estimated by the numerical iterative algorithm through a graphic method. In order to verify the algorithm, this article establishes a relatively accurate model, which takes the inductance asymmetry and detent force into account. Simulations are carried out to obtain the difference between the actual and estimated positions. Experiments are carried out for further verification. Finally, system simulations and experiments are carried out. The results of experiments show that the initial position estimation based on this algorithm can significantly improve positioning and control accuracy.