【作者】 刘颖；

【导师】 周波；

【作者基本信息】 南京航空航天大学 ， 电力电子与电力传动， 2012， 博士

【摘要】 永磁同步电机因其具有结构简单、功率密度高和效率高等优点，成为了电气传动系统驱动电机的发展趋势。在永磁同步电机控制系统中，转子位置与转速信息必不可少，常用同轴安装的机械式位置传感器直接测量；然而，机械式位置传感器会增加系统的体积和成本，并限制该系统在一些高温、强腐蚀性场合的运用。为克服这些弊端，无位置传感器技术被提出并受广泛关注，成为了当前电气传动领域最为活跃的研究方向之一。本文对永磁同步电机无位置传感器控制技术的研究现状进行了综述，研究表明，实现电机低速时转子位置与转速估计的难度较大。因此，本文紧紧围绕表贴式永磁同步电机的零速和低速时无位置传感器控制，采用脉振高频信号注入法进行了深入的研究。首先分析了永磁同步电机的结构特点、数学方程和矢量控制策略，对有位置传感器下转速、电流双闭环系统进行了仿真和实验分析。进而，采用无位置传感器技术，针对零速和低速时控制，分析了三种传统高频信号注入法无位置传感器的基本原理和实现方法，它们分别是旋转高频电压注入法、旋转高频电流注入法和脉振高频电压注入法。而本文以表贴式永磁同步电机为研究对象，前两种方法要求电机具有明显的结构凸极性，只有最后一种方法能够用于无结构凸极性的表贴式永磁同步电机。实现永磁同步电机无位置传感器控制的首要问题是转子初始位置检测，本文提出了一种表贴式永磁同步电机转子初始位置检测的新方法。它是基于定子电感非线性饱和特性，在估计的两相旋转坐标系的直轴上注入高频电压信号，通过闭环调节得到转子位置初次估计值，再利用不同磁极下直轴等效电路时间常数不同的特性，判断出估计直轴正方向，结合初次估计值，得到正确的初始位置信息。该方法在任意初始位置情况下能够快速、准确地检测出转子初始位置，而且系统无需改变或添加硬件电路。检测到转子初始位置后，需要进行零速和低速时无位置传感器控制。在对传统脉振高频电压注入法进行了深入分析的基础上，提出了一种新型脉振高频电压注入无传感器零速和低速的控制方法及位置估计误差补偿策略。首先，在建立电机高频模型时考虑了定子相绕组电阻的影响，设计了转子位置与转速估计系统，并提出了一种新的调制信号形式，克服了不同参数下电机高频阻抗变化可能导致位置估计系统不稳定的缺点，实现了电机起动和低速时无位置传感器控制系统可靠运行；其次，针对随着转速的升高，转子位置估计值与实际值之间的误差会逐渐变大的问题，分析了电压方程中的反电动势和交叉耦合项的影响，提出了一种估计误差补偿策略，加入补偿后能够改善位置估计值对实际值的跟踪精度。在研究了脉振高频电压注入法的基础上，提出了一种新型脉振高频电流注入的低速无位置传感器控制方法。该方法是在估计的两相旋转坐标系的直轴上持续注入高频电流信号，通过检测电流环调节器输出的交轴电压，并对其进行适当的信号处理，从中提取出与转子位置估计误差的信息，对此误差量进行调节，可以获得转子位置与转速的估计值。该方法相较于传统脉振高频电压注入法，优点在于不仅省去了电流反馈时所必须的的两个低通滤波器，系统构成更简单；而且，估计系统不会受到电机定子绕组电阻和电感参数变化影响，稳定性更强。最后，设计了永磁同步电机控制系统的硬件平台和软件系统，对本文所提方法的理论分析和仿真研究进行了实验验证。更多还原

【Abstract】 Permanent magnet synchronous motor (PMSM) has become the main trend of the electrictransmission system drive motor because of its simple structure, high power density and highefficiency. In PMSM control system, the precise information of the rotor position and speed isessential, which can be measured directly by mechanical position sensors. However, some defects arecaused by the installation of mechanical sensors such as increasing the size and cost of the system andlimiting the system’s application area. In order to solve the problem, the sensorless control technologyis proposed. It has been the industrial and academic research focus and becomes one of the mostactive research directions in the field of the electric drive system.In this paper the research about sensorless control of PMSM is reviewed, which shows that toachieve sensorless control at low speed is more difficult. Therefore, focused on estimating the rotorposition and speed of the surface mounted permanent magnet synchronous motor (SPMSM) at lowand zero speed without a position sensor, the pulsating high frequency signal injection method iscarried out in-depth research.First of all, the mathematical model of PMSM and the principle of vector control are analyzed.The static and dynamic performance analysis of the speed and current closed-loop system with theposition sensor is carried out by simulation and experiment. Furthermore, using the sensorless controltechnology instead of the position sensor for zero and low speed control, the basic theory andrealization of three traditional sensorless control methods at are analyzed. These methods are therotating high frequency voltage injection method, the rotating high frequency current injection methodand the pulsating high frequency voltage injection method. Only the last one can be used for SPMSMwithout structural saliency.The most important issue of sensorless control is the initial rotor position detection. A newmethod for the initial rotor position detection of SPMSM without any rotational transducer ispresented. It is based on the nonlinear saturation characteristics of the stator inductance. The methodis realized in two steps. Firstly a high frequency sinusoidal voltage signal is injected into the estimatedsynchronous rotating coordinate system, thus the first estimated value of rotor position can beestimated through closed-loop adjustment. Then pole polarity is determined using different timeconstant characteristics of d-axis equivalent circuit under different poles. Combined with theestimated value, the correct initial position can be obtained. The proposed method can realize fast and accurate initial position detection. Moreover it does not add any hardware circuit.The initial rotor position is detected, and then the sensorless control at zero and low speed isrequired. Based on the depth analysis of the traditional pulsating high frequency voltage signalinjection method, a novel sensorless control method of SPMSM at low speed and a scheme ofestimated position error compensation are presented in this paper. On one hand, considering theimpact of the stator phase winding resistance, the motor high-frequency model is established. Thenthe position and speed estimation system is designed and a form of modulation signal is proposed,which can realize any arbitrary initial rotor position detection at zero speed and steady operation atlow speed. On the other hand, for the reason that the increment of error between the estimatedposition and the real one emerges with the speed increased, leading to uncertainty operation of system,a scheme of estimated position error compensation considering the fundamental frequency back-EMFand cross coupling terms is proposed. Precisely rotor position tracking can be achieved with thescheme.On the basis of the pulsating high frequency voltage injection method, a novel sensorless controlmethod of SPMSM based on high frequency current signal injection is proposed. A high frequencysinusoidal current signal is superimposed into the estimated d-axis, and the rotor position can bedemodulated after q-axis voltage is regulated, which is relative to error angle. Ultimately the rotorposition and speed can be obtained exactly at low and zero speed. Compared to the pulsating highfrequency voltage signal injection method, the proposed method is not only simpler in structurebecause it eliminates the need for two low pass filter in the current feedback loop, but also more stablethe position and speed estimation system because it is not subject to the changes of motor resistanceand inductance parameters.Finally, the hardware platform and the software system of the PMSM control system aredeveloped. Experiments can be carried out to verify the theoretical and simulation analysis of theproposed method in this paper.更多还原