Research On Motor Driver Control Technology Of Electric Car

Today, undering the background of world energy saving and environment protection are facing the great pressure, with high and new technology development, many countries are developing new energy vehicles, energy-saving and environment-friendly cars. Compared with the internal combustion engine, electric cars due to its advantages of can make the air and noise pollution significantly reduce in the cities and also can make the energy utilization more reasonable, widely welcome by the all countries. Especially at present in the situation of the battery technology has not get breakthrough development, motor drive system in electric car application is particularly important.In this paper, for electric drive control system need high instantaneous power, wide speed range, high efficiency during operation and has a high overload capacity,etc to meet the requirements of electric cars, we adopts permanent magnet synchronous motor (PMSM) speed sensor-less direct torque control methods to control motor drive.Analyzes and compares the advantages and disadvantages of several common motor, choose permanent magnet synchronous motor as the drive motor.The mathematical model of PMSM was studied, and introduces the basic principleof direct torque control, in order to overcome the faults of traditional torque motor two point adjust which are existing slowing response slow and electromagnetic torque ripple, this paper proposes SanDianShi torque regulation.For PMSM direct torque control system, using sensors will have the problems of reducing system reliabilityand increasing system cost, in order to reduce the influence of traditional sensor system, this paper also do some researche on speed sensorless technique.In order to realize the high-performance of PMSM speed sensor-less direct torque control, based on mathematical model of PMSM, this paper proposes speed estimation method which is based on the rotor flux vector Angle of motor to estimate speed. This paper uses Matlab/Simulink software to structure simulation modeof direct torque control system without speed sensor. From the simulation results can be seen, adopting rotor flux vector Angle speed sensor-less instead of direct torque control system with speed sensor, the method to achieve direct torque control speed sensor-less scheme is feasible and effective.In addition, DSP (TMS320LF2812) of TI Corporation is used as the core-processing chip of the control system, and Intelligent Power Module (IPM) is used as the power switch component. The hardware of the system is designed based on DSP and IPM, and software for speed sensor-less direct torque control is designed. Finally, we debug the hardware by means of SPWM method easily realized. Results show the motor driving control system which is used in this article,which the dynamic response speed and control accuracy and efficiency and vehicle performance can satisfy the basic requirementsof electric vehicle.