多源多变换微电网系统建模与动态稳定分析方法

微电网内部电力电子变换器接口型分布式电源广泛存在.电力电子接口微源具备与传统电力系统电源拓扑结构、控制方法和动态特性的差异性,控制方法的多样性、电力电子接口微源高渗透率将给低惯量微电网的协调控制和安全稳定运行带来严峻的挑战.多类型微源、多类型负荷在微电网内混合共存,可能引发源源耦合交互、负荷间交互以及源荷交互,不同特性的设备间相互作用将重新塑造区别与传统电力系统的动态响应特性,并诱发稳定性问题.本文首先归纳总结可再生能源渗透率不断提升下多源多变换微电网典型运行特性和存在的稳定性问题,详细阐述了含风光柴储多源多变换接口的微电网模块化动态建模方法.在此基础上,给出了用于微电网动态稳定分析的特征值分析方法和基本步骤.以珠海东澳岛多源多变换智能微电网为对象,基于提出的动态建模方法和动态稳定分析方法,给出建模与分析讨论结果.论文对多源多变换微电网系统动态稳定分析方法的论述可为微电网的广泛推广和应用提供建模和分析理论基础.

Modeling and dynamic stability analysis method of microgrids with multiple energy resources and multiple conversions

Power-electronic-converter (PEC) based distributed generations (DGs) are widespread in microgrids, and they differs significantly from the conventional synchronous generators in control schemes and dynamic characteristics. The diversity of DG control methods and the increasing penetration of PEC DGs are leading to various challenges in coordinated control and stable operation of low-inertia microgrids. The coexistence of heterogeneous microsources and loads within the microgrid may result in interactions among the DGs and loads. The coupling among the devices with different characteristics reshape the dynamic responses of the microgrids and induce stability issues. In this paper, firstly, typical operating characteristics and stability issues of the microgrids with increasing penetrations of renewable energy resources are summarized. The modularized dynamic modeling method of microgrid with multiple energy resources and multiple conversions interface is described in detail. On this basis, the eigenvalue analysis method and basic steps for dynamic stability analysis of microgrid are given. Furthermore, the proposed dynamic modeling and dynamic stability analysis method are adopted to model and analyze the Dongao Island smart microgrid. The discussion of the dynamic stability analysis method of the multiple energy resources and multiple conversions microgrid system can provide the theoretical foundation for the modeling and analysis of the microgrid extension and application.