基于虚拟同步发电机的微电网控制策略的研究

发布时间：2018-01-31 04:26

本文关键词： 微电网虚拟同步发电机零逆流蓄电池　出处：《安徽理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：微电网是大电网的重要补充。但是传统的控制策略无法做到孤岛运行时对微电网电压和频率的无差控制,尤其是负载波动时会严重影响到微电网的安全稳定运行。当微电源发电功率大于负载功率时,微电网中能量的逆流也会对大电网造成不利的影响。本文以基于虚拟同步发电机控制的微电网为研究对象,在稳定微电网电压和频率的同时,实现微电网的零逆流。本文首先介绍微电网的概念和结构,以及国内外微电网的发展现状。同时分析微电网运行时并网与孤岛控制,并深入研究微电网的协调控制和不同接口策略的控制方法。其次,考虑到微电网中的微电源缺少物理惯性,即没有同步发电机的转动惯量,本文将虚拟同步发电机控制运用到微电网中。通过对同步发电机的转子机械特性和定子电气特性的深入分析,将同步发电机的控制运用到微电源中,使得微电源能够克服上述弱点,并在功频控制器和励磁控制器的调节下维持系统的频率和电压的稳定。同时为了防止微电网中多余的能量逆流进入大电网,造成大电网的谐波增加并危害到负荷用电安全,设计蓄电池作为微电网的储能装置。当微电源发电功率大于微电网负载功率时,通过零逆流的功频控制器的调节,使得蓄电池按照指令充放电,将多余能量储存,以满足对微电网零逆流的要求。论文对微电网主电路中的LC滤波器和连接感抗的参数进行理论分析和计算,确定实际应用中参数的取值范围。最后,使用MATLAB/Simulink软件搭建仿真模型,仿真结果表明该方法满足微电网的性能要求。将虚拟同步发电机的控制策略运用到微电网中,既能解决电压和频率的无差控制,又能实现微电网对大电网的零逆流。从性能的角度来看,此方法有着很好的应用前景。
[Abstract]:Microgrid is an important supplement to large power grid, but the traditional control strategy can not achieve the islanding voltage and frequency control. Especially when the load fluctuates, it will seriously affect the safe and stable operation of the microgrid. The countercurrent of the energy in the microgrid will also have a negative impact on the large grid. In this paper, the micro-grid based on the virtual synchronous generator control as the research object, while stabilizing the voltage and frequency of the micro-grid. The zero countercurrent of microgrid is realized. This paper first introduces the concept and structure of microgrid, as well as the development of microgrid at home and abroad, and analyzes the operation of microgrid and islanding control. The coordinated control of microgrid and the control methods of different interface strategies are deeply studied. Secondly, considering the lack of physical inertia of micro-power supply in microgrid, that is, the moment of inertia of no synchronous generator. In this paper, the virtual synchronous generator control is applied to the micro-grid, and the control of the synchronous generator is applied to the micro-power supply through the in-depth analysis of the rotor mechanical characteristics and stator electrical characteristics of the synchronous generator. The micro power supply can overcome the above weaknesses and maintain the stability of the frequency and voltage of the system under the regulation of the power and frequency controller and the excitation controller. At the same time, in order to prevent the superfluous energy countercurrent in the microgrid from entering the large power grid. It causes the harmonic increase of large power grid and endangers the safety of power consumption. The storage battery is designed as the energy storage device of the microgrid, when the generation power of micro-power is larger than the load power of micro-grid. By adjusting the zero countercurrent power and frequency controller, the battery is charged and discharged according to the instruction, and the excess energy is stored. In order to meet the requirement of zero countercurrent in microgrid, the paper analyzes and calculates the LC filter and connection reactance parameters in the main circuit of microgrid, and determines the range of parameters in practical application. MATLAB/Simulink software is used to build the simulation model. The simulation results show that the method meets the performance requirements of microgrid. The control strategy of virtual synchronous generator is applied to microgrid, which can not only solve the no-difference control of voltage and frequency, but also realize the zero countercurrent of micro-grid to large power grid. From the point of view of performance. This method has a good application prospect.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM31

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