电力系统时滞稳定判据保守性差异量化评估方法

摘要

基于Lyapunov稳定理论的时滞稳定判据,已被广泛应用于各类电力系统时滞稳定性分析.由于采用了不同的Lyapunov函数和不同的推导过程,不同的稳定判据往往会具有不同的外在形式、计算效率和保守性.文中借助数值计算方法和可视化技术,分析揭示不同时滞稳定判据在保守性方面表现各异的内在原因,为寻求更为科学的时滞稳定判据提供支撑.首先,在简单回顾时滞系统模型的基础上,引出几种常用的时滞稳定判据.进一步,借助时滞系统仿真数据引入了3类反映系统运行差异性的指标,并给出了一种用于评估电力系统时滞稳定判据保守性的数值计算方法.最后,通过一阶典型单时滞系统详细说明了该评估方法的应用过程,并利用单机无穷大单时滞系统和3机9节点时滞系统验证所提方法在多维系统及多时滞场景下的有效性.%The time-delay stability criterion based on the Lyapunov stability theory is commonly used to analyze the time-delay stability of power systems.Owing to the different Lyapunov functions and derivation processes adopted, different stability criteria tend to have different forms, computational efficiency and conservative properties.This paper tries to explain the difference in conservative properties by numerical calculation and a visualization method to provide guidance for seeking better criteria.First, four typical time-delay stability criteria are introduced based on a simple review of the time-delay system model.Furthermore, three kinds of indices reflecting the operational diversity of the power system are introduced by time-delay system simulation data.Then a numerical calculation method for evaluating the conservatism of time-delay stability criteria for power systems is presented.Finally, the application process of the evaluation method is shown by a typical first-order system.The effectiveness of the proposed method in multi-dimensional systems and multi-time-delay scenarios has been validated by a single-generator-infinite-bus system and a WSCC 3-generator 9-bus time-delay system.