Analytical model for armature reaction of outer rotor brushless permanent magnet DC motor

Abstract

This study presents an analytical model for calculating the armature reaction magnetic field of outer rotor permanent magnet brushless DC motor (PMBLDCM) in stator stationary coordinate system (SSCS) and rotor rotation coordinate system (RRCS). Firstly, an expression of armature reaction magnetic field of single-phase winding is deduced, without considering slotting effect. Afterwards, analytical expressions of armature reaction magnetic field in both SSCS and RRCS regardless of slotting effect are obtained using vector addition method. Then complex relative permeances of outer rotor BLPMDCM in SSCS and RRCS are analysed, respectively. Finally, analytical solutions of the armature reaction magnetic field in both SSCS and RRCS are derived, respectively, by multiplying the slotless armature reaction magnetic field and the complex relative magnetic permeance, the self-and mutual inductance are calculated by the armature reaction magnetic field. A 46-ploes-51-slots outer rotor BLPMDCM is set as an example, the accuracy of proposed analytical model is verified by the Finite Element Method. Based on this analytical model, the pattern of slotting effect on armature reaction of both outer rotor and internal stator are analysed, respectively, as well as spatial order characteristics and frequency characteristics of armature reaction for outer rotor PMBLDCM in SSCS and in RRCS.

Additive Manufacturing of Shaped Profile Windings for Minimal AC Loss in Electrical Machines

“…Although highly computationally efficient, analytical methods of estimating the armature reaction field, [26], [27], and AC losses within conductors, [8], [28], tend to require reformulation when the machine topology changes, assume linear magnetically permeable materials or are restricted to regular, repeated conductor shapes. Therefore a 2D Finite Element (FE) modelling approach is adopted which allows arbitrary shaped conductors to be easily represented and lends well to changes in machine topology.…”

Influence of static eccentricity on unbalanced magnetic force of external rotor permanent magnet brushless direct current motor used as In‐wheel motor

“…However, there is no in-depth study of the source of UMF in the rotor coordinate system in [12]. In [13] and [14], the analytical expressions of the no-load air-gap magnetic field and the armature reaction of a PMBLDCM were deduced. The spatial-order characteristics and frequency characteristics were studied in [13] and [14].…”

“…In [13] and [14], the analytical expressions of the no-load air-gap magnetic field and the armature reaction of a PMBLDCM were deduced. The spatial-order characteristics and frequency characteristics were studied in [13] and [14]. However, there has been no study on the on-load air-gap magnetic field and the UMF of PMBLDCM with eccentricity.…”

Permanent Magnet Brushless DC Motor and Mechanical Structure Design for the Electric Impact Wrench System

“…The leakage path of interior magnet motors usually includes a saturable magnetic bridge and the web, which will make the coefficient of flux leakage variable. Some studies [18][19][20][21][22][23][24][25][26][27] have been done on Brushless direct current motor (BLDC) design for different applications at different power levels. However, most of them used the computer-aided tools and experience to get the BLDC motor parameters, which usually takes time.…”