光纤通道路径不一致对线路差动保护的影响

Influence of the fibre route with difference on line differntial protection

光纤分相电流差动保护依赖光纤通道。光纤通道的来回路由时间直接影响差动保护的性能。推出基于采样时刻调整法同步的光纤差动的同步相差与光纤通道来回路由时间差的关系,并分析光纤通道收发路由不一致时,差动保护在区外故障和区内故障的动作行为,得出在通道来回路由不一致的时间差在5 ms以内时,选择合适的差动制动系数完全可以使用。文章还给出了两种新的差动保护解决方案来适应光纤路径的不一致:在差动保护中增加GPS同步法和增加允许式纵联距离。

The line differential protection relays on optical channel.The differential time of the receiving route and the sending route directly influences the performance of differential relay.The paper illustrates the relationship between the differential time of the transmission channel and the differential phasor of synchronization.It analyses the differential relay’s performance of internal fault and external fault when the fibre route of sending and receiving is not equal.And it acquires that the line differential relay can be used in the differential time of the come-and-go transmission less than 5ms if the bias coefficient is rational.Finally,the paper gives two methods to solve the problem.It is to add GPS synchronization or POTT in the line differential protection.