Research And Development Of AC Motor Control System Based On FOC

With the continuous improvement of the AC motor control theory, a wide range of the applications of GTO devices and PWM technology, as well as the popularity of high-performance DSP chips, AC motor with the advantages of its small size, low cost, high reliability, maintenance-free, large output power, etc, have been rapidly replacing the DC motors in many control areas, and have similar performance with DC motors.In the drive control field of electric vehicles , the AC motor controller with its high-performance, high power density, high reliability, low cost, low pollution and good environmental adaptability characteristics etc, increasing access to a wide range of applications, and towards to a digital, can be optimized, etc.Response to market demand, this paper research a DSP-based AC motor controller, which using field oriented control method and SVPWM algorithm to meet the application requirements of the electric pallet cars, forklifts, electric vehicles and so on.This paper provides a brief analysis and elaboration of mathematical model of AC asynchronous motor. Through the analysis of the principle of field-oriented control(FOC) and the mathematical model which in different coordinate system, the basic principle of AC asynchronous motor FOC vector control system are described. This paper described the principle of PWM modulation, based on this the SVPWM modulation technique described in detail, and SVPWM modulation algorithm are simulated. Simulation result shows the effectiveness of the SVPWM algorithm.For the realization of rapid agile,real-time characteristics and so on, which electric vehicles drive control system needs, in the choice of the control chip, using TI's high-performance control chip TMS320LF2407A, analyze hardware and software design in detail. The Hardware interference issues are due considered in design process. At the same time during the design process the method of dead-time compensation is studied.In order to verify the feasibility of the designed system, the dynamic and static characteristics are simulated using Simulink of MATLAB. Based on this, do the experimental development of on-board system for software testing, debugging results show that the algorithm which has dead-time compensation function can be output the current waveform ,which close to ideal sine wave, to achieve reliable, high-performance control of AC asynchronous motor.