Combined optimization of a linear PM actuator with trapezoidal PMs and coils considering fringing effect for precision engineering

Article type: Research Article

Authors: Chen, Jun-Wei^a;

Affiliations: [a] College of Information Science and Engineering, Jiaxing University, Jiaxing, China E-mails: cjwbuaa@163.com, cjwbuaa@zjxu.edu.cn

Correspondence: [*] E-mail: cjwbuaa@163.com, cjwbuaa@zjxu.edu.cn

Abstract: For precision engineering, a linear PM-moving actuator with trapezoidal PMs and trapezoidal coils considering the fringing effect is proposed. To take into account the effect of the finite-long trapezoidal PM array, an improved Fourier series expansion is developed to calculate the fringing-included magnetic field. Then the full-stroke thrust excited by the trapezoidal coils is accurately predicted and validated by the finite element method. Sensitivity of the trapezoidal parameters of PMs and coils is analyzed, and combined optimization is implemented by the genetic algorithm. Through the Pareto optimal solutions of thrust, the relation of the PM-coil parameter combination is described and formulated by curve fitting. Compared with the traditional rectangular PM actuators or other trapezoidal-typed actuators, the proposed actuator with trapezoidal PMs and coils further decreases the thrust ripple and largely increases the thrust magnitude simultaneously, and reaches an utmost-close effective stroke as well.

Keywords: Trapezoidal PMs, trapezoidal coils, linear PM actuator, fringing effect, Fourier series expansion, combined optimization

DOI: 10.3233/JAE-210050

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 68, no. 4, pp. 405-425, 2022