Development Of Control System For Vehicle Induction Motor Based On TSPWM

As part of the electric car,the low-speed electric vehicle has been favored by residents of three or four line urban because of its low cost,convenient short trip in recent years and have huge market potential.The drive motor is the core component of the electric vehicle,its life directly affects the cost of electric vehicles,which has become a concern of low-speed electric vehicle manufacturers.However,when using the space vector pulse width modulation(SVPWM)in the two level inverter of low speed electric vehicle,the high frequency alternating common mode voltage(CMV)will be formed on the AC induction motor(ACIM).The CMV will cause the shaft current that will damage the motor bearing and shorten the service life of the motor.In order to solve the above problems,firstly the working principle of the two level voltage source inverter and its common mode voltage mechanism were analyzed,the vector control theory and the mathematical model of the induction motor were analyzed in this paper.Secondly,the basic principle of suppressing the common mode voltage of tristate pulse width modulation(TSPWM)was introduced,and an improved TSPWM to minimize the switching loss of the inverter was put forward,and the basic method of TSPWM to realize vector control was expounded.Then,in the Matlab/Simulink environment,the ACIM vector control simulation model based on TSPWM was established,the correctness and feasibility of TSPWM and its optimization method applied to ACIM vector control system was verified through the simulation,and the upper layer control strategy was developed based on model design and automatic code generation technology.Infineon XMC4200 and DAVE3 development environment were introduced briefly,the method of TSPWM combined with XMC4200 to produce the novel PWM signal was expounded.The underlying drivers,such as ADC,POSIF,MultiCAN communication module and so on,were developed by visual programming APP of DAVE3,and the upper control strategy and the underlying drivers were integrated in DAVE3.The main circuit of the motor controller with XMC4200 as its core including power circuit,JTAG debug interface circuit,oscillator circuit,reset circuit,magnetoelectric speed sensor signal processing circuit,current sampling circuit,temperature and voltage sampling circuit and CAN communication circuit were designed,signal processing program was developed based on the hardware circuit.The experimental platform of eddy current dynamometer platform was built,the common mode voltage of the induction motor under the control of SVPWM and TSPWM was compared and the effect experiment of the improved TSPWM was tested,and the experimental results and analysis were given.The no load the load test of the induction motor using the developed control system were carried out.The experimental results showed that the common mode voltage for induction motor control system can be obviously inhibited by the control system of vehicle induction motor based on TSPWM,the motor applied with this system can output constant high torque at low speed,and run continuously with constant power,high efficiency at high speed,which can meet the requirements of electric vehicle drive output torque in a wide speed range,the system had good dynamic performance and meet the requirements of the induction motor control system for low-speed electric vehicles.