基于权值评估的Lyapunov时滞稳定判据改进方法  

Method for Improving Efficiency of Delay Stability Criterion Based on Weight Value Analysis of Lyapunov Functional Items

作　　者：王蕾[1] 贾宏杰[1] 董朝宇 

机构地区：[1]智能电网教育部重点实验室(天津大学),天津市300072

出　　处：《电力系统自动化》2017年第16期111-116,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51625702)~~

摘　　要：在含有时滞环节的电力系统稳定性分析中,基于Lyapunov稳定理论和线性矩阵不等式(LMI)技术的时滞稳定判据被广泛采用。然而,这类判据往往存在计算量大、计算效率低的问题,尤其在高维系统中计算效率迅速降低,亟需寻求科学手段来提高判据计算效率。对此,文中借助数值计算方法,分析了Lyapunov函数各构成项随时间的变化规律及各项占函数的权值,进而提出一种通过权值计算来甄别Lyapunov函数冗余项的有效方法。通过剔除冗余项,减少了判据的待求变量数,在不影响判据保守性前提下,有效提高了计算效率。最后,通过典型二阶时滞系统和3机9节点时滞系统分别对两种Lyapunov时滞稳定判据进行简化改进,验证了文中方法的有效性。The delay stability criterion, based on the Lyapunov stability theory and linear matrix inequality（ LMI）, is widely used in stability analysis of the power system with time delays. However, it is hardly applicable to high dimensional systems where time consumption is high and computation efficiency low. The number of variables to be calculated increases by a factor of square as the dimension of the state variable increases. For this reason, a numerical calculating method is used to study the time-varying properties of each item of Lyapunov functions to obtain the weight of each item. Then a delay stability criteria improved method is proposed, in which redundant items of the functions are identified and deleted to improve the efficiency of the stability criterion without increasing its conservatism. Finally, the delay stability criteria improved method is used for two criteria in a typical second-order-system and a 3-machine 9-bus system with two time delays to verify the efficiency of the proposed method.

关 键 词：Lyapunov函数简化 时滞稳定判据 计算效率 权值 电力系统稳定 

分 类 号：TM712[电气工程—电力系统及自动化]