节点文献
基于载波频率成份法的永磁同步电机无位置传感器控制研究
Research on Position Sensorless Control of Permanent Magnent Synchronous Motor Based on Carrier Frequency Component Method
【作者】 于艳君；
【导师】 程树康；
【作者基本信息】 哈尔滨工业大学 ， 电机与电器， 2009， 博士
【摘要】 永磁同步电机(Permanent Magnet Synchronous Motor,PMSM)无位置传感器控制系统是高性能电驱动控制领域的研究热点。载波频率成份法(Carrier Frequency Component Method,CFCM)利用逆变器本身的载波频率成份,无需外加高频激励就能实现电机在全速域内的无位置传感器运行,已成为无位置传感器控制研究的一个重要方向。因此,本文对基于载波频率成份法实现的永磁同步电机无位置传感器控制系统及其相关问题进行了相应的理论分析和应用研究,主要工作如下:文中建立了永磁同步电机在常用参考坐标系下的数学模型。采用双重傅立叶变换和Bessel理论对正弦波PWM调制中两种常见的载波方式进行了深入分析和比较,推导了逆变器输出的载波频率成份电压方程,确定了三相三角载波调制方式适用于载波频率成份法。研究了永磁同步电机在α-β轴系和γ-δ轴系下的载波频率成份模型,根据三相载波调制下两个两相参考轴系的电流峰值方程推导了电机转子位置的估算公式,并给出了理论分析结果。采用载波频率成份法估算电机转子位置时,系统参数以及逆变器非线性效应会对估算结果产生影响,本文对此进行了深入的分析和研究。首先,分析了电机转速、负载以及电机凸极比变化对转子位置估算误差的影响。其次,分析了逆变器载波频率大小对转子位置估算精度以及电机定子电流质量和电磁转矩脉动的影响,为逆变器载波频率的选择提供了依据。再次,在分析逆变器非线性效应的基础上,研究了非线性效应对基于CFCM实现的PMSM无位置传感器控制系统性能的影响,并提出了补偿措施。正确辨别转子的初始位置极性对实现永磁同步电机无位置传感器控制十分必要。为了解决电机转子的初始位置极性检测问题,文中研究了永磁体磁势和电枢磁势共用作用下的电机电感特性,并进行了有限元分析和实验验证。在此基础上建立了电机磁饱和情况的磁链和电感模型,利用d、q轴磁路饱和程度的不同,采用外差法实现了三相载波调制下永磁同步电机转子初始位置极性的辨别,并进行了仿真和实验验证,为实现高性能永磁同步电机无位置传感器控制创造了条件。为了提高系统的动态响应和抗扰动性能,控制系统采用Anti-windup控制器。针对永磁同步电机控制系统中实际存在的积分饱和现象,在传统PID控制器设计的基础上对系统控制器进行改进,设计了采用Anti-windup控制器和CFCM实现的永磁同步电机无位置传感器控制系统。最后,设计了一套永磁同步电机无位置传感器控制系统实验装置。采用三相载波调制方式下的载波频率成份法实现了永磁同步电机的无位置传感器运行,并对内置式永磁同步电机进行了实验验证。实验结果证明了该方法对具有空间凸极性的永磁同步电机无位置传感器控制的有效性和可行性。理论分析、仿真研究和实验验证表明:本文所研究的基于逆变器载波频率成份法的永磁同步电机无位置传感器控制系统,通过跟踪转子的空间凸极性实现了电机转子位置的估算,使得这种方法对电机参数的变化不敏感,可实现电机宽速域内的无位置传感器运行等特点,是一种实现无位置传感器控制行之有效的方案。
【Abstract】 Position sensorless control of permanent magnet synchronous motor (PMSM) is a focal point in the research domain of the high performance electric drive and control. Carrier frequency component method (CFCM) can realize position sensorless control over full speed range. In the method, the signal of the PWM inverter carrier frequency component is used as the rotor position information source. No additional injection signal is required. CFCM has become an important direction in the research of the position sensorless control. In this paper, the corresponding theory and application of the position sensorless control system for PMSM based on CFCM is studied. Major work is as following:PMSM mathematical models in common reference frames are analyzed. Two familiar carrier modes of SPWM are deeply analyzed and compared by using double Fourier transform and Bessel theory, and then the mathematical model of the inverter’s output voltage is derived. The conclusion can be drawn that the modulation using three-phase triangular wave carrier can be suitable for CFCM. Mathematics models of carrier frequency component in theα-βandγ-δframes are established. According to the above analysis, the rotor position of PMSM is estimated and the results of theoretical analysis are given.The deeply analysis on parameters and inverter nonlinearity effect in the electrical machine system is studied in this paper, because of its influence in estimating the rotor position by CFCM. Firstly, the effects of estimating accuracy by the changes of motor’s speed, load and motor’s saliency ratio are analyzed. Secondly, carrier frequency not only affects the accuracy of rotor position’s estimation, but also affects the quality of current and ripple of electromagnetic torque. So choice of carrier frequency is analyzed in this paper. Thirdly, the performance of the position sensorless control system by the influence of the nonlinearity effects is studied, based on the analysis of inverter nonlinearity effects, in the meantime, compensation strategies are proposed.For position sensorless PMSM system, identifying the initial magnetic polarity of the rotor position correctly is very important. In this paper, inductance characteristic under the action of permanent magnet magnetic motive force and the armature magnetic motive force is considered, and its Finite Element Analysis (FEA) and experiment are carried. On this basis, flux linkage and inductance mathematical models are established considering the saturation. Identification of the initial magnetic polarity is realized by using heterodyne method, utilizing the different levels of magnetic circuit saturation in the d axis. Simulation and experiment are done to test this theory. These works make effort to realize the high-performance application of position sensorless PMSM.In order to improve the system performance of dynamic response and disturbance rejection, anti-windup controllers are used to control the PMSM system. Firstly, the design of the conventional PID controller is improved aimed at the saturation phenomenon of system integral. Position sensorless control system of PMSM is designed based on an anti-windup controller and CFCM.Experimental equipment of position sensorless system for PMSM is designed. The motor system position sensorless operation is realized using the CFCM under three-phase triangular carrier modulation, and it’s verified by the experiment of interior PMSM. The result indicates that this method is effective and feasible for the position sensorless control of salient synchronous motor.Theoretical analysis, simulation and experimental studies show that position sensorless synchronous motor control system based on CFCM of PWM inverter has plenty of advantages, such as the smaller sensitivity of electric parameter and the realization of system wide-speed operation, etc, which is an effective proposal to realize position sensorless motor control system.