Modeling and detection of demagnetization fault in permanent magnet vernier machine using flexible magnetic equivalent circuit method

Abstract

In this paper, an analytical model is proposed for evaluating electromagnetic performances of permanent magnet vernier machines (PMVMs) under healthy and faulty conditions. The proposed model employs flexible magnetic equivalent circuit (MEC) method, which its accuracy can be selected by tunable parameters. The model is capable of considering the influence of saturation effect, skewed slots, slot leakage fluxes, and various winding arrangements for the machines with desired properties. First, the proposed model is used to predict the no-load performance of machine at healthy condition. Then, the machine loading behaviors under healthy and demagnetization fault conditions are analyzed by the MEC model. Moreover, the results of the proposed model are compared and validated with those of 2D finite element method (FEM) and 3D-FEM. Eventually, a specific pattern is extracted from the stator current spectrum to detect the demagnetization fault.

A comprehensive analysis on a novel DC‐Excited Flux‐Switching Linear Motor as a new linear vehicle for transportation systems

“…The Nf and Ns are the turn number of each coil, and Ln is considered for modelling of Y and Y N connection of the phases windings. Clearly, Ln → ∞ indicates ia + ib + ic = 0 in which Y denotes connection, and the Y N connection can be modelled by Ln = 0 [22, 29–31]. Notably, the end‐effect is an important phenomenon that should be considered for accurate analysis of the linear machines.…”

“…Noticing Figures 1, and 2, the main parameters are tabulated in Table 1. In Equation (), μ r ( B ) is a non‐linear function for saturation effect as written in Equation (), where the B‐H curve of the flux tubes can be fitted on the actual martial curve by a , b , c , and d parameters [22–27, 29, 31]. $$$R{i}_{j}=\left\{\begin{array}{ll}\frac{l{i}_{j}}{{\mu }_{0}.$$…”

“…[22, 30]. The whole system equations preparation in a matrix form can be obtained by the presented method in Refs. [29, 31]. The conversion of differential equations into algebraic time‐stepping form can be obtained according to the presented technique in Ref.…”

“…The whole system equations preparation in a matrix form can be obtained by the presented method in Refs. [29, 31].…”

“…Noticing the performed research in Refs. [22, 24–27, 29, 31], the final equations in the matrix form can be obtained as Equation (), where details of the used sub‐matrices as well as the symbols are completely illustrated in Refs. [22, 29].…”