含不同微源接口的微网建模及稳定性分析

发布时间：2018-07-17 20:00

【摘要】：随着大电网以及分布式发电技术的弊端日渐显现,微电网由于其众多优势成为研究热点。微电网与传统大电网有较大差异,主要体现在微电网中具有较多种类的微源。微电网技术的发展离不开先进的控制策略,而微电网建模及稳定性分析是微电网控制器设计及控制策略优化的理论基础,研究微电网建模及稳定性具有重要意义。本文根据微电源接口的不同,将微源分为同步发电机、异步发电机和逆变器接口的微源。为了分析微网中该三种不同接口类型微源之间的交互影响及多类型微源并存对微电网稳定性的影响,本文详细推导出了同步发电机、异步发电机和电压源型逆变器三种典型接口微源的小扰动稳定性分析模型并通过网络坐标变换将三者联合,推导出了9阶微网小扰动模型。其中,为了分析不同控制策略下系统参数变化对微电网小扰动稳定性的影响,针对电压源逆变器型微源提出了PQ和PV两种控制策略并详细推导了其小扰动模型。进而提出了适用于含多同步发电机、多异步发电机以及多逆变器接口微源的微电网拓展小扰动模型。在Matlab中编程实现微电网并/孤网情况下特征值计算并分析了两种运行工况下的微电网稳定性。最后通过系统主导特征根对不同参数的灵敏度计算,分析并比较了PQ和PV控制策略下系统参数变化时微电网稳定性,得出了可为微电网控制提供决策依据的结论。
[Abstract]:With the development of large power grid and distributed generation technology, microgrid has become a research hotspot because of its many advantages. There are great differences between microgrid and traditional large power grid, mainly reflected in the microgrid with more kinds of micro-sources. The development of microgrid technology can not be separated from advanced control strategies. The modeling and stability analysis of microgrid is the theoretical basis of microgrid controller design and control strategy optimization. It is of great significance to study the modeling and stability of microgrid. In this paper, the microsource is divided into synchronous generator, asynchronous generator and inverter interface according to the different microsource interface. In order to analyze the interaction between the three kinds of microsources and the influence of the coexistence of multi-type microsources on the stability of microgrid, a synchronous generator is derived in this paper. The small disturbance stability analysis model of three typical interface microsources of asynchronous generator and voltage source inverter is presented and the nine order microgrid small disturbance model is deduced by network coordinate transformation. In order to analyze the influence of system parameters on the small disturbance stability of microgrid under different control strategies, two control strategies, PQ and PV, are proposed and their small disturbance models are derived in detail. Furthermore, the extended small disturbance model of microgrid with multi-synchronous generator, multi-asynchronous generator and multi-inverter interface microsource is proposed. The eigenvalues of microgrid are calculated and analyzed under two operating conditions by programming in Matlab. Finally, by calculating the sensitivity of system dominant characteristic root to different parameters, the stability of microgrid under PQ and PV control strategy is analyzed and compared, and the conclusion that can provide decision basis for microgrid control is obtained.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM711

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