新型电力系统主动构网机理与技术路径

Mechanism and Technical Path of Active Grid-forming of New Type Power System

随着新一代“双高”电力系统的发展,新能源并网变换系统逐渐由随网型向构网型演变,当新能源机组集群运行时,并网情况将更加复杂。变换器的构网能力需亟待研究,同时也是电力能源转型需承担的重要使命。该文立足并网系统内外形态的全局性和传统并网变换系统性能分析的局限性,对并网变换器的主动构网支撑机理进行再揭示。首先,对虚拟同步技术与构网机理进行简要评述;其次,就集群并网系统的建模问题、多机集群并网运行时的耦合交互问题、支撑构网能力的储能配置和运行边界等3个关键技术问题,进行深入研究;最后,针对上述3个关键技术问题,进行技术路径探索和研判。该文的思路为形成适用于未来新能源集群并网运行的系统化理论和实用化方法奠定一定基础。

With the development of a new generation of"double-high"power systems,the new energy grid-connected conversion system has gradually evolved from a grid-connected type to a grid-connected type.When the new energy units are running in clusters,the grid connection situation will be more complicated.The grid construction capability of the converter needs to be studied urgently,and it is also an important mission for the transformation of electric power.Based on the globality of the internal and external forms of the grid-connected system and the limitations of the performance analysis of the traditional grid-connected conversion system,this paper re-reveals the support mechanism of the grid-connected converter's active grid construction.First,the virtual synchronization technology and network construction mechanism are briefly reviewed.Then,three key technical issues,such as the modeling of cluster grid-connected system,the coupling interaction of multi-machine cluster grid-connected operation,and the energy storage configuration and operation boundary supporting the grid construction capability,are deeply studied.Finally,technical path discussions and judgments are made for the above three key technical issues.The idea of this paper is to attract others and lay a preliminary work for the formation of a systematic theory and practical method suitable for the grid-connected operation of new energy clusters in the future.