【作者】 王铮；

【导师】 史婷娜；

【作者基本信息】 天津大学 ， 控制科学与工程， 2014， 硕士

【摘要】 永磁同步电机(PMSM)具有结构简单、功率因数高、转矩电流比大等优点,在工业场所得到了广泛应用。在永磁同步电机系统矢量控制过程中,转子位置和转速信号是必不可少的反馈量,这些信息可以通过光电编码器、旋转变压器及位置速度观测算法得到。其中,绝对式编码器能够直接读取电机的转子位置,适合应用于永磁同步电机系统中。此外,在永磁同步电机系统控制过程中,测量转速作为反馈信号用于跟踪给定转速,因此,测量转速的质量必然会影响电机的运行性能。为此,本文主要围绕测量转速对电机运行性能的影响以及电机控制相关问题展开了一系列研究。首先本文详细地分析了绝对式编码器的测量机理,对传统测速方法的测速误差与时间延时进行了分析。其次,从理论角度分析了测速精度和时间延时对电机运行性能的影响。为解决传统测速方法所存在的测量精度低和延时时间长以及改善传统卡尔曼观测器的动态性能差的问题,本文提出了一种测量噪声自适应卡尔曼观测器,该观测器主要根据弥补绝对式编码器的测量误差和提高算法的动态跟踪性的思想所设计的。根据永磁同步电机数学模型设定观测器的参数值,使得该观测器可以用于观测电机转子位置、转速与负载转矩。在电机运行状态突变的情况下,本文提出的观测器实时计算当前的测量噪声,并对增益矩阵进行更新,以确保算法的准确性与及时性。此外,将卡尔曼观测器观测的信号作为永磁同步电机矢量系统中的速度反馈信号和负载补偿信号,构建永磁同步电机前馈-反馈控制系统,提高了电机系统的抗扰性能和转速跟踪性能。本文搭建永磁同步电机系统控制平台,并在该实验平台上进行了自适应卡尔曼观测器的实验验证。实验结果表明测速方法中的测量精度与时间延时会影响电机的运行性能;本文所设计的自适应卡尔曼观测器能够准确及时地观测电机转子位置、转速及负载转矩,将所观测的转速和负载转矩用于前馈-反馈控制中,可以提高永磁同步电机系统的动、静态性能。更多还原

【Abstract】 Permanent magnet synchronous motor(PMSM) has been widely used in the industrial areas due to its simple structure, high power factor, big torque current ratio, etc. In the process of vector control of permanent magnet synchronous motor system, rotor position and speed signal are the necessary feedback signals, which can be obtained by an optical encoder, rotary transformer and an algorithm of position and speed measurement. Among them, an absolute encoder can read the motor rotor position directly, which is suit to permanent magnet synchronous motor system. In addition, the measurement speed is used as a feedback signal to follow the given speed in the control process of the PMSM system, thus the quality of the measurement speed affects the motor working property necessarily. The paper mainly conducts some researches around the influence of the measurement speed on the motor working property and the relevant aspects such as motor control.The paper firstly detailed analyzes the measure mechanization of the absolute encoder, and the mathematical analyses about speed measurement error and time delay of traditional speed measuring methods are done. Then the influences of the speed measurement error and time delay on the motor working properties are analyzed in a theoretical point. In order to solve the problems of low speed measurement precision, long time delay of traditional speed measurement methods and improve the bad dynamic performance of the traditional Kalman observer, this paper proposes a measurement noise self-adaption Kalman observer, it is designed on the ideas of making up measurement noise of the absolute encoder with limited resolution ratio and improving the dynamic tracking ability of the algorithm. Based on the mathematics model of PMSM, the parameters of the observer are designed to observe the rotor position, speed and load torque. In the condition that the motor working state has a sudden change, the proposed observer calculates the current measurement noise in real time and updates the gain matrix which can ensure the precision and no-time-delay of the algorithm. In addition, to improve the anti-disturbance and speed tracking abilities of the motor system, a PMSM feed-forward and feedback control system is built using the observed signals as the speed feedback signal and load compensation signal.The paper builds an experimental platform of permanent magnet synchronous motor system to make an experimental research on the proposed self-adaptive Kalman observer using in the PMSM system. The experimental results show that the precision and time delay of speed measurement method affect the motor working property. The proposed self-adaptive Kalman observer can observe rotor position, speed and load torque timely and precisely. Using the observed speed and load torque into the feed-forward and feedback control can improve the dynamic and steady properties of the permanent magnet synchronous motor.更多还原