Temperature Field Of Motor Under Complicated Working Conditions

The purpose of calculating the temperature field of the motor is to investigate the temperature change of the motor,the calculation of temperature field generally is carried out under the stable heat source.The actual operation state of the motor depends on the working system and specific working environment,this complex working condition of non-single working system is complicated working conditions.Its unstable heat source will cause the motor temperature field to be in a transient process all the time,the calculation method of stable heat source temperature field is difficult to check the limit temperature.To solve the problem of calculating the temperature field of the motor under complicated working conditions,the most important feature is unstable heating.Taking the self-cooling induction motor with small closed structure motor as the research object,a two-dimensional electromagnetic field-temperature field multi-field coupling solution model is established by using finite element method.According to the two-dimensional multi-field coupling model,the parameters are calculated and modified equivalently.It includes the calculation of thermal conductivity and radiation heat dissipation coefficient of stator slot in temperature field model parameters,the calculation and equivalent of convection coefficient of stator and rotor,heat dissipation coefficient of shell surface,and the calculation and correction of end winding and start transient parameters in electromagnetic field model parameters.Based on the analysis of the characteristics of unstable heating under complicated conditions,the design of coupling calculation process and the configuration of coupling calculation parameters are carried out.The transient temperature field of the motor with unstable heat source under complicated conditions is calculated by multi-field coupling method.According to the characteristics of unstable heat source under complicated working conditions,the temperature distribution of transient temperature field in the whole region of the motor and the temperature variation law of typical parts such as rotor,stator winding,iron core and shell are analyzed.A temperature field experimental platform is established to test the whole transient temperature field of the motor under complicated working conditions.The simulation results and experimental results are compared and analyzed to verify the accuracy of the multi-field coupling method and the equivalent treatment of model parameters,and to reliably investigate the temperature rise of the motor when the heat source is unstable.