一种包含不确定参数的暂态稳定分析方法

动态电力系统是一个非线性、多变量、强耦合的系统,由于大量参数的不确定,建立精确的模型比较困难。该文基于UUB(一致最终有界)定理,提出一种利用二次型的Lyapunov函数分析多机均匀阻尼经典模型中参数不确定性对暂态稳定影响的解析方法。通过比较某一运行方式下的计算指标与极限指标来判断该系统的参数偏差是否会引起暂态稳定性的变化。对两个算例进行了一系列仿真,结果表明该方法结果尽管保守,但简单、可靠、容易实现。

A Method for Analyzing the Impact of Parameter Uncertainties on Transient Stability

Dynamic power system is a nonlinear multivariable system. It is rather difficult to set up a precise model due to the parameter uncertainties. Based on the UUB (uniformly ultimately bounded) theory and a quadratic Lyapunov function, this paper provides a methodology to analyze the influence of parameter uncertainties on transient stability under the classical model with uniform damping coefficients. We suggest a method to judge whether the stability characteristics will be changed or not by comparing the limit index and the calculated index in some operating point. In addition, two numerical examples are described, indicating the reliability and simplicity of this approach in spite of its conservative side.