基于滑模变结构控制的风力发电机组双PWM变流器的设计与仿真研究

发布时间：2018-12-31 12:57

【摘要】：随着全球经济的快速发展,人类对能源的需求日益增加。由于地球上煤炭、石油等常规资源日益匮乏,并且对常规资源的利用也会给环境带来许多污染问题,所以为了解决能源和环境问题,我们在合理的利用煤炭、石油等常规资源的同时,必须大力发展利用可再生资源。而风能作为一种安全、环保、新型的可再生能源,取之不尽、用之不竭。随着风力发电技术的成熟,风力发电的成本也在不断地降低。而在风力发电领域,直驱型风力发电机组已经成为一个重要的研究方向。本文基于直驱式风力发电机组对双PWM变流器的控制策略进行了分析和研究,将滑模变结构的控制策略应用在双PWM变流器的控制系统中,并在MATLAB仿真软件中建立风力发电系统的仿真模型,通过仿真实验,证明本文所提出的设计方法是可行的。本文主要针对直驱风力发电机组双PWM变流器的控制系统进行了建模和仿真研究。首先,本文介绍了直驱永磁风力发电系统的基本结构及其相关特性,并详细介绍了各组成部分的基本原理,在此基础上建立了各组成部分的数学模型,具体包括风力机模型、传动系统模型、永磁同步发电机模型、双PWM变流器的数学模型、中间直流环节的数学模型。其次,重点介绍了滑模变结构控制的基本原理,针对非奇异终端滑模在离平衡点较远处动态性能差的缺点,设计了一种具有快速收敛性的非奇异终端滑模面。并基于滑模变结构控制原理下分别设计了网侧PWM变流器直流侧电压、d轴电流、q轴电流的滑模控制器,并详细介绍了SVPWM脉宽调制的基本原理及其实现方法。第三,先介绍了最大功率点跟踪(MPPT)方法和永磁同步发电机的矢量控制原理,重点阐述了基于最佳叶尖速度比的最大功率点跟踪控制和零d轴电流矢量控制的实现方法,并在此基础上介绍了机侧PWM变流器的转速外环、电流内环的双闭环控制原理。然后基于滑模变结构控制理论设计了机侧PWM变流器的转速、d轴电流、q轴电流的滑模控制器。最后在风力发电系统中对永磁同步发电机无位置传感器的控制进行了研究,设计了滑模观测器模型,并利用该模型估计永磁同步发电机转子转速和转子位置,来代替位置传感器的作用,实现了永磁同步发电机无位置传感器控制。最后,在MATLAB仿真软件中搭建了网侧PWM变流器控制的仿真模型、机侧PWM变流器控制的仿真模型以及滑模观测器的仿真模型。接着对风电系统的整体模型进行仿真实验,通过仿真结果分析可知,本文设计风力发电机组的双PWM变流器的控制策略能够实现风能的最大功率点跟踪,并且实现电网电压的单位功率因数并网,控制系统具有良好的动态性能和稳态性能。并在此基础上,建立了基于滑模观测器的风力发电系统的仿真模型,通过仿真分析可知,基于滑模观测器的风力发电系统能够对永磁同步发电机的转子转速和转子位置进行精确地估算,实现了对永磁同步发电机的无位置传感器控制。
[Abstract]:With the rapid development of the global economy, human demand for energy is increasing. Because of the increasing shortage of conventional resources such as coal and oil on the earth, and the utilization of the conventional resources can bring a lot of pollution to the environment, in order to solve the problems of energy and environment, we can reasonably utilize the conventional resources such as coal, oil and the like, The use of renewable resources must be vigorously developed. As a safe, environment-friendly and new type of renewable energy, wind energy is inexhaustible. With the mature of the wind power generation technology, the cost of wind power generation is also decreasing. In the field of wind power generation, the direct drive type wind generating set has become an important research direction. In this paper, the control strategy of the dual PWM converter is analyzed and studied based on the direct drive type wind generating set, and the control strategy of the sliding mode variable structure is applied to the control system of the dual PWM converter, and the simulation model of the wind power generation system is established in the MATLAB simulation software, It is proved that the design method proposed in this paper is feasible. In this paper, the modeling and simulation of the control system of the double-PWM converter of the direct-drive wind-driven generator set are studied. Firstly, this paper introduces the basic structure and related characteristics of the direct-drive permanent-magnet wind power generation system, and introduces the basic principle of each component in detail. On this basis, the mathematical model of each component is established, including the wind turbine model and the transmission system model. The model of the permanent-magnet synchronous generator, the mathematical model of the double-PWM converter and the mathematical model of the intermediate DC link. Secondly, the basic principle of the sliding mode variable structure control is introduced, and a non-singular terminal sliding mode with fast convergence is designed for the disadvantage of the dynamic performance difference of the non-singular terminal sliding mode at the far distance from the equilibrium point. Based on the control principle of the sliding mode variable structure, the DC side voltage, the d-axis current and the q-axis current of the grid-side PWM converter are respectively designed, and the basic principle of the SVPWM pulse width modulation and its realization method are introduced in detail. Thirdly, the method of maximum power point tracking (MPPT) and the principle of the vector control of the permanent magnet synchronous generator are introduced, and the realization method of the maximum power point tracking control and the zero d-axis current vector control based on the optimal blade tip speed ratio is given. On the basis of this, the double closed-loop control principle of the rotating speed outer ring and the current inner ring of the machine-side PWM converter is introduced. Then, the rotational speed, d-axis current and q-axis current of the machine-side PWM converter are designed based on the sliding mode variable structure control theory. In the end, the control of the position sensor of the permanent magnet synchronous generator is studied in the wind power generation system, the model of the sliding mode observer is designed, and the rotor speed and the rotor position of the permanent magnet synchronous generator are estimated by the model to replace the position sensor. and the position sensor control of the permanent-magnet synchronous generator is realized. Finally, the simulation model of the control of the network-side PWM converter, the simulation model of the machine-side PWM converter and the simulation model of the sliding mode observer are set up in the MATLAB simulation software. then the whole model of the wind power system is simulated and tested, and the simulation result analysis shows that the control strategy of the double-PWM converter of the wind generating set can realize the maximum power point tracking of the wind energy and realize the unit power factor of the grid voltage and the network, The control system has good dynamic performance and steady-state performance. On the basis of this, the simulation model of the wind power generation system based on the sliding mode observer is established, and the simulation analysis shows that the wind power generation system based on the sliding mode observer can accurately estimate the rotor speed and the rotor position of the permanent magnet synchronous generator, and the position-free sensor control of the permanent-magnet synchronous generator is realized.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM315;TM46

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