异步电机矢量控制及磁链观测器的研究

发布时间：2018-03-13 18:11

本文选题：异步电机　切入点：矢量控制　出处：《哈尔滨工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：伴随着科学技术的进步，控制策略研究的逐渐深入，异步电机变频调速系统在工业各个领域得到了广泛的应用，同时对异步电机的控制性能提出了越来越高的要求。本文在异步电机矢量控制的基础上，着重研究了几种常见的磁链观测的结构组成，对参数的敏感性以及自抗扰控制器（ActiveDisturbance Rejection Control, ADRC）在异步电机中的应用进行研究。在坐标变换的基础上得到在两相旋转坐标系下的异步电机的数学模型，作为本文的研究的基础。然后，提出了本文所使用的关于异步电机矢量控制的定向方式：按照转子磁场的方向进行定向。并且分析研究了在实际使用过程中可能用到的两种不同的电流闭环方式：滞环控制以及SVPWM控制。通过对比异步电机在两种控制方式下结果的不同，得到本文电流闭环控制方式的基础：SVPWM控制。由于在基于转子磁链定向的控制系统中，转子磁链的观测结果对于整个控制系统十分重要，因此本文着重研究了几种转子磁链观测环节：包括两种开环磁链观测环节以及两种闭环磁链观测环节的基本结构并对其进行仿真研究。但是仿真条件下与实际系统运行过程中存在差别，仿真基于理想的情况下，但在异步电机的运行过程中，参数不会像在理想状态下时一直保持恒定，会发生变化，这些变化会令我们在实际系统中无法准确观测磁链信息进而影响电机控制的准确性。因此我们研究了在参数变化时对磁链观测结果造成的影响，通过对观测值与实际值做比值并通过分析比值在频率特性下的曲线，从而可以得到在参数变化时，各种参数对不同磁链观测器的具体影响，，以求能够通过理论来指导实际应用。最后分析得出，开环模型收到电阻电感影响较大，闭环模型较开环模型受到参数变化的影响小。由于在电机运行过程中，会产生很多不确定因素，基于异步电机的复杂的结构特性以及PI调节器会产生鲁棒性受限等问题。本文ADRC有针对性的应用在异步电机调速系统中并且在此基础上通过MATLAB进行仿真，主要通过研究空载启动，增加负载，转速给定变化时的仿真结果，并与基于PI调节器控制的仿真结果进行对比。
[Abstract]:With the progress of science and technology and the development of control strategy, the frequency conversion speed control system of asynchronous motor has been widely used in various fields of industry. At the same time, the control performance of asynchronous motor is demanded more and more. Based on the vector control of asynchronous motor, this paper focuses on the structure of several common flux observation. The sensitivity of parameters and the application of active Disturance Rejection Control (ADRC) in asynchronous motor are studied. On the basis of coordinate transformation, the mathematical model of asynchronous motor in two-phase rotating coordinate system is obtained, which is the basis of this paper. In this paper, the directional mode of vector control for induction motor is proposed, which is orientated according to the direction of rotor magnetic field, and two different current closed loop modes which may be used in practical use are analyzed and studied. Hysteresis control and SVPWM control. By comparing the results of the asynchronous motor under the two control modes, In this paper, the current closed loop control method of the basic control: SVPWM control. In the rotor flux oriented control system, the rotor flux observation results are very important to the whole control system. Therefore, this paper focuses on several rotor flux observation links, including two open-loop flux observation links and two closed loop flux observation links, and simulates them. But under the simulation conditions and the actual system. There are differences in the operation of the system, The simulation is based on ideal conditions, but in the operation of asynchronous motor, the parameters will not be kept constant and will change as in ideal state. These changes will make it impossible for us to accurately observe the flux information in the actual system and thus affect the accuracy of the motor control. Therefore, we have studied the effect of the variation of the parameters on the flux observation results. By comparing the observed value with the actual value and analyzing the curve of the ratio under the frequency characteristic, the specific influence of various parameters on the flux observer can be obtained when the parameters change. In order to guide the practical application through the theory, it is concluded that the open-loop model has greater influence on the resistance inductance, and the closed-loop model has less effect on the parameter change than the open-loop model. Because during the running of the motor, there are many uncertain factors, Based on the complex structure characteristics of asynchronous motor and the limitation of Pi regulator, this paper applies ADRC to speed regulation system of asynchronous motor and simulates it by MATLAB. The simulation results of no-load startup, load increase and speed change are studied, and compared with the simulation results based on Pi regulator control.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM343

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