基于李雅普诺夫方法的电力系统静态频率稳定分析

Analysis of Power Systems Static Frequency Stability Based on Lyapunov Methods

提出了基于李雅普诺夫方法的电力系统静态频率稳定分析方法,为判断系统静态频率稳定性和有效防止静态频率失稳提供了依据。首先建立了等值单机电力系统的有功功率-频率静态模型,然后在发电机组无调速系统下,推导了基于李亚普诺夫间接法和直接法的静态频率稳定依据,最后考虑发电机有快速调速系统时,利用李亚普诺夫方法分析了电力系统静态频率稳定的条件。研究结果表明:发电机组没有调速系统,系统阻尼系数大于临界阻尼时,系统可保持静态频率稳定;发电机组有快速调速系统下,系统阻尼比为正数时,系统可保持静态频率稳定,且充足的热备用容量有利于保持系统的静态频率稳定。

This paper proposes a static frequency stability of a power system based on Lyapunov methods,which provides a basis for judging the static frequency stablity of system and effectively preventing the static.Firstly,the active power-frequency static model of equivalent single machine power system is established.And then,the stability criterion on static frequency stability is derived based on lyapounov indirect and direct method when the generator has no speed control system.At last,the condition of static frequency stability of the system with fast speed control system is also analyzed by Lyapunov methods.The results show that when the electric generator does not have a speed regulating system and the system damping coefficient is greater than the critical damping,the system can maintain the static frequency stability.When the electric generator has a speed regulating system with a positive damping ratio,the system can maintain static frequency stability,and sufficient hot spare capacity is beneficial to maintaining the static frequency stability of power system.