采用低分辨率位置传感器的正弦波永磁同步电机控制系统

　　采用低分辨率位置传感器的正弦波永磁同步电机控制系统
　　In recent years, due to the development of permanent magnetic material, permanent magnet synchronous motor is widely used. According to the difference of back electromotive-force (EMF) and cunent waveform, permanent magnet synchronous motor is divided into trapezoidal permanent magnet synchronous motor (Brushless DC motor) and sinusoidal permanent magnet synchronous motor (Permanent magnet synchronous motor). In order to achieve sinusoidal current control, sinusoidal permanent magnet synchronous motor usually requires high resolution position sensor such as encoder or resolver to obtain exact rotor position information. Such sensors add length to the machine, reaise the system cost, increase rotor inertia, and is easily affected the environment factors. rare earth magnets Many sensorless drive solutions have been proposed to eliminate position sensors for PMSM in recent years. However, these solutions still exist other problems, for example, they are very difficult to control and obtain exact rotor position information, and also the range of speed is limited. In order to resolve above-mentioned problems,
　　we study obtaining high resolution position estimation from the low resolution sensors to achieve sinusoidal current drive.Firstly, in this paper the traditional position estimation method is theoretically analysised which adopts average rotor speed in position section or average rotor speed along with average rotor acceleration rate in position section. In order to solve the insufficiency of traditional methods, this paper proposed one improved method which estimates the initial speed in position section to advance the estimative precision of the speed and rotor position. This paper establishes models of above-mentioned three methods in matlab and simulations are conducted in http://www.chinamagnets.biz order to analyze the methods. The results show the improved method can maintain little error at accelerating or decelerating process and the performance has obviously surpassed the traditional methods.Secondly, in this paper a prototype control system of sinusoidal permanent magnet synchronous with low resolution position sensors based on TMS320LF2407A is constructed. The hardware of the control system includes TI’s DSP TMS320LF2407A, IR’s diver IR2110 is designed and made by the author. Studying the control strategy of sinusoidal permanent magnet synchronous motor without current sensor, the paper finds voltage phase is very important in the performance of PMSM. In order to obtain optimal φ= f(ω) curve, we must optimize the curve according as the load characteristics.At last the software of sinusoidal permanent magnet synchronous with low resolution position sensors is designed based on TMS320LF2407A. This paper discusses the position estimation software and SVPWM software in detail and has carried on experiment to confirm it.