Generation-transmission-load Coordinative Expansion Planning Considering Node Inertia Vulnerability Assessment

The frequency safety issue of the power system is becoming increasingly evident under the high proportion of new energy access. In the initial stage of the disturbance, insufficient inertial resources or unreasonable distribution may lead to a rapid drop in frequency, which is an important factor affecting the frequency safety. To improve the overall construction efficiency of the system and ensure its inertia response capability during operation, it is necessary to consider the influence of the source, network and load side resources on the system’s inertia support capability of the system during planning. In this paper, a node inertia vulnerability assessment method is proposed, which utilizing the characteristics of initial disturbance power probability distribution and power grid information to evaluate the node inertia support capacity. The traditional ordered clustering algorithm has been improved, and a refined clustering method for load-new energy scenario reduction based on comprehensive class diameter is proposed. Meanwhile, a method for vulnerability evaluation of node inertia is proposed, utilizing the initial disturbance power probability distribution characteristics and network information to evaluate the node inertia support capability. By integrating generation-transmission-load side resources, a generation-transmission-load collaborative planning model is established and its solution process is designed for optimal solution. Finally, the validity of the model is verified through examples, and the influence of inertial constraints on the system planning results is discussed.