Study On Multi-physical Field Analysis And Optimal Design Of AC Traction Motor Drive System

AC Traction Motor（AC Traction Motor）is the main driving force source in the current industrial field.It is an advanced Traction technology developed in the 1980 s.AC traction motor has many advantages,compared with DC traction motor,AC traction motor structure is relatively simple,small volume,speed range is large,power density is also large;Compared with permanent magnet motor,AC traction motor has high reliability and relatively simple control strategy.Based on the above advantages,AC traction motor is widely used in urban rail transit locomotives.For the AC traction drive system itself,to meet the basic electromagnetic performance is the premise of the motor design,but for the motor controller,it is also necessary to control the temperature rise.In order to take into account the comprehensive performance requirements of the AC traction motor drive system,this paper will use the finite element method to comprehensively analyze the AC traction motor drive system from the perspective of multiple physical fields.This work will be of great significance to the design of the AC traction motor drive system.In this paper,the research of the ac traction motor drive system is mainly used in urban rail transit systems,due to the motor using conditions and the use of special environment,which requires the drive system of the motor has higher comprehensive performance,therefore,in this paper,the research emphasis on ac traction motor of the electromagnetic properties and the cooling system for optimization design of the controller.According to the structural characteristics and requirements of the AC traction motor for urban rail transit,the coupling numerical algorithm is used to analyze the AC traction motor,and the preliminary structural parameters of the AC traction motor are determined based on the concrete engineering examples,and the two-dimensional finite element model of the AC traction motor is established.Then the multi-physical field of the motor is theoretically analyzed,and the torque and current characteristic curves of the AC traction motor under rated voltage,under-voltage and over-voltage are analyzed.Then,the relationship between motor slot size parameters and motor efficiency was obtained through simulation experiments under different rotor slot sizes,and the response surface method was used to analyze the relationship.The rotor parameters of the motor were optimized by fitting function.For the motor drive system,the heat dissipation function of the controller directly affects its overall performance,so the performance optimization analysis of the controller is essential.Aiming at the heat dissipation problem of the motor controller,the internal heat dissipation was firstly analyzed,and then the heat flux coupling temperature rise model was established to analyze the temperature rise distribution law of the width of the radiator,the number of radiator bars and the height of the radiator bars in detail.Considering the comprehensive impact of the width,number and height of the radiator tendons on the vehicle performance,the best combination of the three is finally determined,and the comprehensive temperature rise of the motor controller is analyzed.By physical fields more comprehensive analysis and optimization of controller parameters,to produce the controller heating panel prototype,and design the related performance testing,the method of building the experiment platform of radiator,measured by experiment data,a further contrast experimental data and simulation data calculation results,verify the coupling simulation analysis method is effective.