基于相对熵组合赋权法的继电保护定值在线校核顺序研究

为了使继电保护定值在线校核更高效合理,提出了按照保护综合重要度对继电保护定值进行顺序校核。针对现有保护重要度评估中存在评估角度单一的问题,文中综合保护所处网络位置关键程度和保护故障后果严重程度2个角度,构建了保护综合重要度评估模型。首先利用支路有功潮流介数,提出支路重要度指标,以量化评估保护所处支路的关键程度;然后利用保护事故链模型结合风险理论提出保护故障严重度指标,以量化评估保护故障连锁的风险后果;最后提出保护配合度指标,以量化评价保护所处位置的拓扑结构脆弱性。为弥补单一赋权法的局限性,通过相对熵组合赋权法求出各指标权重,进而得到保护综合重要度指标,并以综合重要度排序进行保护定值在线顺序校核。与已有的方法比较,该方法更为全面地评估了保护的重要度,以此确定的保护定值校核顺序更具参考意义。仿真算例验证了该方法的正确性、全面性。

Study on On-Line Checking Sequence for Protective Relay Based on Combinational Weighting Method of Relative Entropy

In order to make the on-line verification of relay protection setting more efficient and reasonable,the online checking sequence is determined by the comprehensive importance of relay protection.Most of the existing protection importance assessment methods fail to present a full view.To solve this problem,this paper takes the importance of network location of the protection and the severity of protection failure into account,and then,the evaluation model of protection comprehensive importance is constructed.Firstly,branch importance is presented by the active power betweenness of branch to quantify the importance of the branch which the protection located at.Then,based on protection fault chain model and risk theory,the severity of protection failure is,proposed to quantify the risk consequence of the chain of protection failure.Finally,coordination degree of protections is proposed to quantify the topological vulnerability of protection location.In order to compensate the limitation of the single weighting method,the weights of each index are obtained by combinational weighting method of relative entropy,and then,the comprehensive importance index of protection is obtained,and the on-line verification sequence of protection setting is conducted by the comprehensive importance index.Compared with the existing methods,this method evaluates protection importance more comprehensively,making the online checking sequence of protection setting more reference significance.In the end,the correctness and comprehensiveness of the proposed method are verified by a simulation example.