多机-多变流器电力系统机电振荡网络能量解析与优化调控研究

随着新能源等以变流器为特征的电力电子装备规模并网，多机-多变流器电力系统逐步形成。易引起系统阻尼特性恶化，惯量降低，加剧机电振荡风险和危害。针对以源侧分析为主的传统方法面临多类型电力电子装备分布多且建模复杂进而加剧分析和调控困难的问题，本项目拟从网络角度并结合能量手段选取振荡关键传播通道（振荡路径）进行多机-多变流器电力系统网络化解析与调控，可避免复杂建模且可局部自适应调控。首先，构建计及多类型电力电子装备动态特性的机电振荡网络能量函数，通过网络能量解析方法研究能量时空分布与振荡特征内在联系；其次，研究多源-多模式下网络振荡路径分布和规律，重点分析多机和多变流器在电网中的交互过程，揭示多机和多变流器与电网耦合作用机制，基于量测手段辨识、追踪和定位系统振荡路径等薄弱环节；最后，提出平抑振荡能量为约束的自适应网络局部广域调控方法。本项目旨在为提高多机-多变流器电网安全稳定水平提供理论支撑。

With the high-proportion grid-connection of new energy and other power electronic equipment featuring converters, the multi-machine and multi-converter power system is gradually formed. It is easy to lead to the deterioration of system damping characteristics and the decrease of inertia, which aggravates the risk and harm of electromechanical oscillation. As to the problem that it is difficult to analyze and control from the source side because of widespread distribution and complex modeling of the multiple types of power electronic equipment, the project is proposed from the perspective of network combined with the energy method to carry out network analysis and regulation by selecting key transmission channel oscillation (oscillation path) of multi-machine and multi-converter power system. Then the complex modeling can be avoided and local adaptive control is carried out. Firstly, the network energy function of electromechanical oscillating with the dynamic characteristics of various types of power electronic equipment was constructed. The intrinsic correlation between spatial and temporal distribution of energy and oscillation characteristics is studied by network energy analysis. Secondly, the distribution and law of network oscillation path under multi-source and multi-mode are studied. The interaction process of multi-machine and multi-converter in the power grid is analyzed, and the coupling mechanism between the multi-machine and multi-converter and the power grid is revealed. Identify, track and locate the oscillation path of the system based on the measurement method. Finally, an adaptive network local wide area control method considering the constraint of oscillation energy suppression is proposed. The purpose of this project is to provide theoretical support for improving the safety and stability of multi-machine and multi-converter power grid.