Analysis On The Loss And Temperature Of Electric Vehicle Motor

Motor using alternating electromagnetic fields to achieve mutual conversion of electricalenergy-mechanical energy. Alternating magnetic field will also generate electromagneticloss in the energy conversion process, and the electromagnetic loss is the main heat source ofmotor temperature field. Accurate analysis of the motor temperature distribution, reducemotor loss has important engineering significance for the motor optimization design, improvestability and prolong motor life.This paper studies the motor loss firstly. By analyzing the change of the alternatingmagnetic field inside the motor to describe the generation mechanism of the electromagneticloss. Establishment of a squirrel-cage three-phase asynchronous motors two-dimensionalfinite element model in electromagnetic analysis software. Analyze the distribution of motormagnetic field lines and magnetic flux density and the variation waveform of the windingcurrent with time. Study the motor electromagnetic loss distribution curve according to themagnetic field and current changes in the motor.Then, according to the basic theory of heat transfer, fluid mechanics to analyze the motortemperature field with finite element method. Simplify motor temperature field calculationmodel according to the structure symmetry characteristics of three-phase squirrel cageinduction motor. Analysis of the computational domain boundary conditions, convert theelectromagnetic loss into heat load, analysis motor steady-state temperature field by finiteelement analysis software Workbench. Drawing the motor three dimensional computationaldomain temperature contours. The results show that the stator winding is the maximum heatsource, so the highest temperature at steady state of the motor. Motor core radial temperaturegradient is smaller than the axial temperature gradient, in particular the rotor core moreapparent. Observe the motor heat transmission path through the heat flux vector. The heatgenerated by the stator core and winding mainly through the chassis for heat exchange withsurrounding. The heat generated by the rotor core and the shaft axial conduction to the endportion firstly and then emitted to the outside the body through the surface of the end portion.Last through prototype contrast, the results of the temperature simulation analysis closeto the actual operation temperature distribution of the prototype.