DEMANGETIZATION RATIO ANALYIS OF PERMANENT MAGNETS FOR DOUBLE V AND DELTA ROTOR SHAPES

Abstract

The irreversible demagnetization due to short circuits the and overheat
temperature effects have been influenced by arrangements of double V and ∇
layer of permanent magnets. This means that the magnetic flux density at the air
gap and electromagnetic forces are also reduced. In addtion, the changes of V
and Delta shape angles of the magnet arrangements will affect directly to
sinusoidal waveforms of the electromagnetic forces due to harmonic
components of the magnetic flux density at the air gap changing flowing to the
rotor shape angle of V magnet layers. In this paper, interior permanent magnet
motors with layered magnets of different shapes (V and ∆) are proposed to
compute and simulate levels of the irreversible demagnetization of permanent
magnets and the waveforms of electromagnetic force due to the overheat of
permanent magnets. Two practical models with speeds of 4500 rpm and
16000rpm under different temperatures will be illustrated.