关键词:

"> 压水堆, 核电机组, 动态仿真, 建模, 网源协调

Abstract:

 [Objecttives] A comprehensive solution is proposed to address the issues of insufficient accuracy in nuclear power plant (NPP) models for large-scale power grid stability simulation-leading to distorted dynamic characteristics—and the lack of coordination mechanisms between grid-related protections and the grid. [Methods] First, a high-precision nonlinear model of the NPP power system is developed, covering the reactor core, primary circuit, and secondary circuit. Key algorithms are introduced, including steady-state equilibrium adjustment and variable initialization under off‑rated conditions, a power interface method based on working fluid enthalpy drop, and a multi‑rate hybrid numerical integration scheme. Furthermore, a model order reduction method combining balanced truncation and singular perturbation theory is proposed, which significantly improves the computational efficiency of electro-mechanical transient simulation for large‑scale grids. Based on the developed model, the interaction mechanism between nuclear power plants and the grid is elucidated. For typical fault scenarios such as over‑frequency, under‑frequency, and under‑voltage, coordinated control strategies between grid‑related protections and grid safety automatic devices are presented. [Results] Simulation results verify the accuracy of the model and the effectiveness of the strategies, providing a powerful tool and research reference for studying the dynamic characteristics of NPPs and their interaction and coordinated operation with the power grid. [Conclusions] The research results can provide powerful simulation tools and research reference for safety and stability analysis and control decision-making of nuclear power units connected to large power grids.

Key words:

text-align:justify, "> pressurized water reactor(PWR), nuclear power plant (NPP), dynamic simulation, modeling, coordination between units and grids