Detent force minimization of an improved linear permanent magnet synchronous motor

摘要

Permanent magnet synchronous linear motors (PMSLMs) have been widely used in industry applications due to their outstanding dynamic characteristics and improved servo-capability. However, the detent force of PMSLM is an inevitable problem, which causes vibration and affects the positional accuracy of the machine. An improved PMSLM structure with arc-teeth and inner-ladder end teeth (AIL-teeth) is proposed in this study to reduce detent force. This structure is advantageous because it not only reduces detent force but also keeps motor size constant. First, the parameters that affect detent force are confirmed using Fourier analysis method. Second, a hybrid optimization method is adopted to obtain the structural parameters of the AIL-teeth PMSLM. The hybrid optimization method is based on the flux-tube and Taguchi methods. The optimal structural parameters of the AIL-teeth PMSLM are determined using the optimization method. Finally, two PMSLMs with traditional and improved structures are contrasted by finite-element analysis (FEA) method and experimental verification, results show that the improved AIL-teeth PMSLM can reduce detent force effectively with the least sacrifice of electromagnetic performance.