An Adaptive Connecting Equivalent Magnetic Network Considering Local
Magnetic Characteristics for SPM Motors
Abstract
Considering the local magnetic characteristics of surface-mounted
permanent magnet (SPM) motors, the paper proposes an adaptive connecting
equivalent magnetic network (ACEMN) model to accurately predict SPM
motor performance. First, for modeling the magnetic field at the
inclined boundary of the stator pole shoe, a diagonal hybrid permeance
element covering two materials is developed. And considering the
parallel magnetization of PMs, a branching calculation of the
magnetomotive force source is performed inside a cross-shaped permeance
of a fan-shaped mesh. Then, by analyzing the phenomenon of magnetic
field line deflection at the air gap boundary, an air gap node
connecting way based on adaptive conversion of connecting permeances is
built. Thereby, the rotating magnetic field of the air gap can be
accurately described using the different connecting permeances with
variable size. To accelerate the nonlinear solution for saturated
element permeability, a hybrid iterative method is used. The validity of
this modeling method is verified by finite element analysis (FEA) and
prototype experiments, which allows a satisfactory compromise between
accuracy and calculation speed.