可靠性度量下的SDH承载配网线路光纤差动保护逻辑优化

Logic Optimization of Optical Fiber Differential Protection for SDH Bearing Distribution Network Lines Based on Reliability Measurement

SDH承载配网的节点分布存在偏差,在分配时难以实现节点互通,对配网光纤分配造成较大影响,无法及时对配网线路进行差动保护。为了提升SDH承载配网线路光纤差动保护的实时性,设计了一种可靠性度量下的SDH承载配网线路光纤差动保护逻辑优化方法。在分层和分割的正交关系设定下,以垂直和水平两个方向划分SDH承载配网光纤的传输结构,形成电路层、通道层以及传输媒介层。按照全电流模式和故障分量模式定义差动保护依据,通过差动保护整定值设定,增加配网线路光纤差动保护的灵敏度。考虑配网线路光纤分配模式,随机选择2组判断变量,以可靠性度量方式建立模型,将相交区域设定为可能出现的故障位置,实现SDH承载配网线路光纤分配的差动保护逻辑优化。实验以内部故障和外部故障两种类型进行差动保护测试,新方法可以不受暂态电容电流影响,将三相差流控制在0 A,具有较高的安全性,且差动保护响应时间低于5 ms,提升了差动保护的实时性能。

There is a deviation in the distribution of nodes in the SDH carrying distribution network,hence,it is difficult to achieve node interoperability during allocation,which leads to a significant impact on the distribution network fiber distribution and prevent differential protection of distribution network lines in a timely manner.In order to improve the real-time performance of fiber optic differential protection for SDH bearing distribution network lines,designed a logic optimization method for fiber optic differential protection of SDH carrying distribution network lines under reliability metrics.Under the orthogonal relationship of layering and segmentation,the transmission structure of SDH carrying distribution network optical fibers is divided in vertical and horizontal directions,which forms a circuit layer,channel layer,and transmission medium layer.Differential protection criteria are defined based on full current mode and fault component mode,and the sensitivity of fiber optic differential protection for distribution network lines increases by setting differential protection settings.Considering the fiber optic allocation mode of distribution network lines,two sets of judgment variables are randomly selected,and a model is established using reliability measurement.The intersection area is set as a possible fault location to achieve differential protection logic optimization for SDH carrying fiber optic allocation of distribution network lines.The experiments conduct differential protection testing with two types of internal and external faults.The new method can be unaffected by transient capacitive current and control the three-phase differential current at 0 A,with high safety.The response time of the differential protection is less than 5 ms,which improves the real-time performance of the differential protection.