Study On Temperature Rise Prediction Of Premium Induction Motor Based On Fluid-heat Coupling

Premium induction motor has the advantages of simple structure,high efficiency,reliable operation,etc.In recent years,efficient motor is widely used in new energy vehicles,aerospace,industrial driving and other fields.Due to the characteristics of small size and single cooling system,the heat dissipation and temperature rise of the motor during operation are directly related to the safe operation of the motor and power system.Therefore,it is very important to study the external fluid field and the temperature rise of each part of an efficient induction motor.Based on an efficient NEMA215T-7.5 k W motor as an example,combined with the cooling structure and actual size of the motor,established a three-dimensional physical model of efficient induction motor.The motor global grid is divided by region,the corresponding boundary conditions are applied,and the rotating fluid field in the wind guide housing is evaluated as the rated speed of the motor by MRF technology.Constructed based on the basic principle of computational fluid dynamics,fluid control equation,using the finite volume method to calculate the effective domain asynchronous motor three dimensional flow field,solving the convection heat transfer coefficient of motor shell,motor is analyzed the fluid and the inlet wind path outside enclosure fluid properties,on the basis of optimizing the ventilation motor outside the wind road structure,improve the motor external fluid properties.For the internal structure of high-efficiency asynchronous motor,based on the principle of heat transfer in the motor,the characteristics of external cooling fluid of the motor are embedded into the motor's thermal rise by means of the fluid-thermal coupling mechanism.In addition,the equivalent thermal network model considering installation mode and cooling mode is established,and the calculation formula of thermal resistance of each part of the Motor is given.The results were compared with the experimental data.Finally,the applicability of finite element method and equivalent thermal network method is compared with the accuracy of calculationresults and the effectiveness of calculation time.In this paper,the optimized calculation method of external wind path and temperature rise of motor can provide reference for the design of similar asynchronous motor cooling system and the study of temperature rise of motor structure and parameters.