Design and Experimental Validation for Direct-Drive Fault-Tolerant Permanent-Magnet Vernier Machines

Abstract

A fault-tolerant permanent-magnet vernier (FT-PMV) machine is designed for direct-drive applications, incorporating the merits of high torque density and high reliability. Based on the so-called magnetic gearing effect, PMV machines have the ability of high torque density by introducing the flux-modulation poles (FMPs). This paper investigates the fault-tolerant characteristic of PMV machines and provides a design method, which is able to not only meet the fault-tolerant requirements but also keep the ability of high torque density. The operation principle of the proposed machine has been analyzed. The design process and optimization are presented specifically, such as the combination of slots and poles, the winding distribution, and the dimensions of PMs and teeth. By using the time-stepping finite element method (TS-FEM), the machine performances are evaluated. Finally, the FT-PMV machine is manufactured, and the experimental results are presented to validate the theoretical analysis.

Quantitative Comparisons of Outer-Rotor Permanent Magnet Machines of Different Structures/Phases for In-Wheel Electrical Vehicle Application

“…High amplitudes and a large variation gradient of armature working harmonic that have the same pole-pair of PMs lead to the high-torque density of PMVMs [14]. In [15], a fault-tolerant PMVM was designed for direct-drive applications, which has merits of high-torque density and high reliability.…”

Analytical sub-domain model for predicting open-circuit field of permanent magnet vernier machine accounting for tooth tips

“…Thus, PMVM is a potential candidate for direct drive application . The most imperative merit of PMVM is that it can produce high torque at low speed (Liu et al, 2014). Furthermore, although concentrated winding is used, sinusoidal back-EMF waveform still can be accomplished, making this machine suitable for synchronous operation ( Jiangui et al, 2010, Ho et al, 2011, Yang et al, 2013, Niu et al, 2010, Li and Chau, 2012, Yusuke et al, 2012.…”