Open AccessInfluence of static eccentricity on unbalanced magnetic force of external rotor permanent magnet brushless direct current motor used as In‐wheel motor
Author(s) -
Ma Conggan,
Cui Hongwei,
Zheng Ping,
Zhang Yuying,
Gao Haibo
Publication year - 2019
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.815
H-Index - 97
eISSN - 1751-8679
pISSN - 1751-8660
DOI - 10.1049/iet-epa.2018.5473
Subject(s) - eccentricity (behavior) , rotor (electric) , stator , physics , magnet , wound rotor motor , finite element method , control theory (sociology) , mechanics , induction motor , computer science , voltage , quantum mechanics , law , thermodynamics , control (management) , artificial intelligence , political science
Here, analytical expressions of the unbalanced magnetic force (UMFof the stator and the rotor under static eccentricity (SE) are deduced by using complex relative magnetic conductivity method and Maxwell stress tensor method. The frequency characteristics of the UMF are obtained. Further the influence of different eccentricity ratio on the UMF is researched. Then, an external rotor permanent magnet brushless direct current motor (PMBLDCM) with 46 poles and 51 slots used as an in‐wheel motor is taken as an example to verify the frequency characteristics by finite element analysis (FEA). The research shows that the frequency characteristics of the UMF of the stator s related to electric frequency. The frequency characteristics of the UMF of the rotor are related to the power source frequency and the rotation frequency of the wheel. It does not introduce new frequency components when the motor SE occurs. As the SE ratio increases, the amplitude of the UMF increases. The UMF without eccentricity exists in all directions with the change of the time. However, as the eccentricity ratio increases, the direction of the UMF is closer to the eccentric direction.