An improved performance prediction model of permanent magnet eddy current couplings based on eddy current inductance characteristics

Abstract

There is a serious nonlinear relationship between slip and torsion of permanent magnet eddy current magnetic couplings (Pmec) and how to establish mathematical model is very important to study characteristics, optimize parameters and improve control accuracy. Based on magnetic equivalent circuit (Mec), Faraday's law and Ampere's law, considering the sensibility of alternating eddy current field, an improved theoretical model of the Pmec is proposed. In this model, greenhouse method is used to describe the inductance of eddy current field, and the factors such as magnetic flux leakage, skin effect and eddy current transverse effect are fully considered. By comparing the proposed model with those of the finite element method (Fem) and experiment, the results show that the proposed model can calculate the torque quickly and accurately without any correction factor. Within the range of 0-100% slip, the predicted torque values of the proposed method match well with those obtained by 3-D Fem and experimental measurements. The proposed model is also proved to be effective in the performance study of the Pmec with different design parameters. The proposed model and 3-D Fem are used to study the influence of structural parameters on the transmission performance of the Pmec, which provides effective reference for the design of the Pmec.