Cooling System Design And Thermal Analysis Of Permanent Magnet Motor For Electric Bus

The rapid development of automobile industry has not only brought great contribution to human society but also caused many negative problems.Developing new energy vehicles and electric vehicle innovation are effective solutions for sustainable and healthy development.The driving motor is the power core of electric vehicle.But the interior space layout is narrow,the heat dissipation condition is limited.The automobile drive motor has a large overload and a large amount of heat,which makes it difficult to dissipate heatTherefore,in the Shenyang Science and Technology Plan Project(17-7-2-00)-the development of the permanent magnet motor for electric bus,the production process of a permanent magnet motor for a certain type of electric bus is used as the background.In-depth study of the design process and heat dissipation process of permanent magnet synchronous motor cooling system for electric bus,the main research contents are as follows:(1)Aiming at the problem of high temperature rise of the driving motor of new energy vehicles,the paper analyzes the operating conditions of electric buses and the working characteristics of the motor,designs the overall motor of the driving motor,and establishes the physical model and thermal power model of the permanent magnet synchronous motor for electric buses.(2)Based on the principle of fluid heat transfer,the overall scheme design of the motor cooling system is completed,with emphasis on the analysis and design of the motor's water cooling housing,so as to effectively reduce the temperature rise of the driving motor for electric buses and realize the power balance of the water-cooling circulating system in the vehicle.(3)In order to verify whether the heat dissipation capacity of the motor is sufficient,the finite volume method is applied to numerically calculate the temperature field distribution of the motor based on the theory of fluid heat transfer control,and the operation results are sorted out and analyzed.The results show that the heat dissipation capacity of the motor can meet the expected goal of the design.(4)According to the theoretical analysis and design,the prototype experiment was carried out.According to the national standard of electric vehicle drive motor,the experimentalscheme of water-cooled automobile motor was designed.The temperature rise experimental data was monitored and collected,and the distribution law of the temperature field of the motor was obtained,and the experimental results were analyzed.The results show that the temperature rise of the prototype meets the expected standard and the optimal water flow is obtained.The design of the cooling system of the motor and the numerical calculation results of the heat dissipation are reasonable and feasible.