Coupled Circuit and Magnetic Model for a Transverse Flux Permanent Magnet Linear Motor

Abstract

In this paper, a strong coupling between magnetic and electric phenomena is provided allowing to have an accurate and high-speed coupled model. A coupled circuit and magnetic model for an E-core transverse flux permanent magnet linear motor (TFPMLM) is proposed, which has an advantage linked to reducing time computing more than ten times when compared to 3-D finite-element model (FEM). Firstly, a multi-plane flexible-mesh nonlinear equivalent magnetic network (EMN) model is proposed to improve the computation efficiency as well as the high precision of the magnetic model. And a new method to define the converged iterative process is presented to further decrease the computing time. Secondly, the magnetic circuit and electric circuit are normalized into a solution matrix by introducing controlled sources and discretization methods which forms the coupled model. Then, the magnetic flux in the magnetic circuits and the current in the electric circuits are obtained simultaneously for each time step. The characteristics such as the air-gap flux density distribution, output thrust force waveforms and the phase currents are analyzed by the proposed coupled model. The modeling approach is approved by comparison with the 3-D FEM model. Finally, the proposed model is validated through the experimental setup with the machine prototype. INDEX TERMS Coupled model, electric circuit, equivalent magnetic network (EMN), linear motor, transverse flux.

A Review of Transverse Flux Machines Topologies and Design

“…The operation, design and modeling of rotating, linear and tubular machines is quite similar (e.g., torque ripple in rotating machines versus force ripple in the linear case), that is why this review is mainly focused on rotating machines. Nevertheless, linear [4,9,10,21,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] and tubular [11][12][13]33,[42][43][44][45][46][47][48][49][50][51][52][53][54] TFMs have specific applications that are presented at the end of this section. In any case, commercial exploitation of TFMs is currently limited to very few manufacturers [55][56][57].…”

Nonlinear Varying-Network Magnetic Circuit Analysis of Consequent-Pole Permanent-Magnet Motor for Electric Vehicles

“…The magnetomotive force (MMF) obtained from PM can be simplified as [24] F PM = B r h m /µ 0 (2) where h m and B r is the thickness and the remanence of PM, separately. Therefore, the MFS of PM, namely Φ PM , can be acquired by…”

“…The nodal analysis and Kirchhoff's Law are employed to establish the magnetic circuit, the basic equation which governs the whole NVNMC model is given by [24] ( )…”

Analytical Optimal Design of a Two-Phase Axial-Gap Transverse Flux Motor

“…TFMs have higher torque and power density than radial-flux machines [9,12,13], so they are specially well suited for direct-drive systems such as robotics [14] or in-wheel traction [4,5,[8][9][10]. Transverse flux machines have been also analyzed as linear motors [15,16] and direct-drive wind generators [17][18][19][20][21][22] using similar techniques. In both cases, motor or generator, the gearbox is eliminated, resulting in a higher efficiency and reliability.…”

“…The torque (reluctance, interaction, and cogging) of a TFM for direct-drive robots is calculated in [14] using 3D flux tubes, and after that a 3D-FEM verification is made. Coupled models (electric and magnetic) have been developed for a linear TFM [15] and the potential of linear TFMs versus longitudinal linear motors has been explored [16].…”