适用于发电系统Well-being评估的改进交叉熵方法  

Improved Cross Entropy Method for Well-being Evaluation on Power Generation System

作　　者：陈凡[1,2] 王宇琦 刘海涛 赵美莲 陈刘明[1] CHEN Fan;WANG Yuqi;LIU Haitao;ZHAO Meilian;CHEN Liuming(School of Electric Power Engineering,Nanjing Institute of Technology,Nanjing 211167,China;Jiangsu Collaborative Innovation Center for Smart Distribution Network,Nanjing 211167,China)

机构地区：[1]南京工程学院电力工程学院,南京211167 [2]江苏省配电网智能技术与装备协同创新中心,南京211167

出　　处：《电力系统及其自动化学报》2022年第8期68-76,共9页Proceedings of the CSU-EPSA

基　　金：江苏省配电网智能技术与装备协同创新中心开放基金资助项目(XTCX201907);南京工程学院科研基金资助项目(CKJB202001);江苏省研究生培养创新工程项目(SJCX20_0720)。

摘　　要：交叉熵法CEM(cross entropy method)用于电力系统Well-being评估时可能出现临界指标收敛速度低于风险指标收敛速度且差距较大,导致出现系统状态抽样效率低下的问题。针对此问题,提出了一种兼顾风险指标和临界指标收敛性的多目标交叉熵方法 MCEM(multi-objective cross entropy method)。该方法通过分别计算针对风险指标和临界指标的随机变量最优分布参数,引入权重系数获取兼顾多指标收敛特性的随机变量综合分布参数,再基于综合分布参数抽取系统状态。同时针对含多状态随机变量的电力系统Well-being评估问题,提出了扩展多目标交叉熵法EMCEM(extended multi-objective cross entropy method)。最后,以IEEE RTS79系统为例进行算例分析,算例结果验证了所提出的MCEM和EMCEM的有效性。When the cross entropy method(CEM)is applied to the Well-being evaluation on power system,it is found that the convergence rate of margin indices may be lower than that of risk indices and the gap is large,which leads to the problem of low sampling efficiency of system states. To solve this problem,a multi-objective cross entropy method(MCEM)is proposed in this paper,which takes into account the convergence of risk and margin indices simultaneously. In this method,the optimal distribution parameters of random variables for risk and margin indices are calculated,respectively,and the comprehensive distribution parameters of random variables considering the convergence characteristics of multiple indices are obtained through the introduction of weight coefficient. Then,the system states are sampled based on the obtained comprehensive distribution parameters. Meanwhile,an extended multi-objective cross entropy method(EMCEM)is proposed for the Well-being evaluation on a power system with multi-state random variables. Finally,an IEEE RTS79 test system is taken as an example,and the analysis results verify the effectiveness of the proposed MCEM and EMCEM.

关 键 词：WELL-BEING 交叉熵 扩展交叉熵 多目标 综合分布参数 

分 类 号：TM74[电气工程—电力系统及自动化]