考虑不确定因素干扰的电网继电保护在线运检方法

Online Operation and Inspection Method of Grid Relay Protection Considering Disturbance of Uncertain Factors

电网继电保护运行会受到大量不确定因素的干扰,为此提出电网继电保护在线运检方法。构建电网继电保护评估指标体系,通过引入变权理论的模糊层次分析法确定指标常权重与变权重系数;通过集对分析理论分析确定与不确定因素干扰之间联系度;引入联系数原理,改进集对分析模型,细化处理指标集对联系度,计算指标隶属度,完成指标集对分析;融合可变模糊集耦合方法,构建基于集对分析-可变模糊集耦合的综合评估模型,并归一化评估指标,计算改进后的集对模糊联系度、综合相对隶属度;计算评价等级状态特征值,采用级别特征值判断方法分析不同指标的状态等级,根据评估情况,获得在线运检结果。经实验验证,该方法能够分析不同继电保护指标在运行过程中所处的状态等级,能够实现不同时间下继电保护的正确动作率、装置缺陷次数、检修情况以及反措情况。

The operation of power grid relay protection is disturbed by a large number of uncertain factors.For this reason,an on-line operation inspection method for power grid relay protection is proposed.The power grid relay protection evaluation index system is constructed,and the constant weight and variable weight coefficient of the index are determined by introducing the fuzzy analytic hierarchy process of variable weight theory.This paper improves the set pair analysis model,refine the index set pair connection degree,calculate the index membership degree,and complete the index set pair analysis.This paper then integrates the variable fuzzy set coupling method to build a comprehensive evaluation model based on set pair analysis-variable fuzzy set coupling,and normalize the evaluation indicators,calculate the improved fuzzy connection degree and comprehensive relative membership degree of the set pair.Experimentally verified that this method can analyze the state level of different relay protection indicators during operation,and can realize the correct action rate,device defect times,maintenance conditions and countermeasures of relay protection at different times.