Introduction To Rotor Eddy Current Loss Of Permanent Magnet Motor For Electric Vehicles

Abstract

In permanent magnet motor, the rotor eddy current loss can make the rotor temperature rise, affect the efficiency of motor performance and even lead to permanent magnet demagnetization. In order to improve the efficiency of the motor and protect the magnet which is core part of the motor, some ways must be adopted to optimize the motor to solve the problem of eddy current. According to the problem of eddy current loss of permanent magnet motor, the principle of eddy current loss was simply analysed in this paper. The eddy current loss can be influenced by the shape of magnet and rotor surface, structure of rotor, slit width of the stator, rotor shield (sheath), air-gap length etc. Some methods of optimizing the eddy current loss were introduced for the further study of the eddy current loss. It is also helpful for the efficiency research of the motor for electric vehicles.

Investigation on the external characteristics of permanent magnet synchronous mechatronic-electro-hydraulic coupler

“…When the frequency and amplitude of the magnetic field remain constant, higher magnetic permeability and electrical conductivity, as well as thicker laminations, can lead to increased stator core eddy current losses. 30 When the stator and rotor iron cores are exposed to a sinusoidal alternating magnetic field, according to the basic principles of electromagnetic fields, the equation for calculating the eddy current loss per unit mass of the stator iron core is:…”

“…When the frequency and amplitude of the magnetic field remain constant, higher magnetic permeability and electrical conductivity, as well as thicker laminations, can lead to increased stator core eddy current losses. 30…”