中文摘要：

分析了目前在实际光纤纵差保护中应用的数据同步方法的缺点，尤其是SDH（synchronous digital hierarchy）光纤自愈环网中收发数据路由不一致导致线路两侧保护装置采样数据不同步问题，提出了一种适用于超、特高压长线路光纤纵差保护的采样数据同步方法，即基于时钟校正法，并通过精确线路模型的在线计算对时钟做进一步补偿校正的方法．EMTP仿真验证该方法的误差小于0．5μs．理论分析和仿真结果证明了该方法保证线路两侧保护装置采样数据同步的有效性及应用于超、特高压长线的可行性．

英文摘要：

The deficiency of conventional synchronization methods, especially the non-synchronous problem caused by the non-conforming routes of receiving and transmitting data in the synchronous digital hierarchy （SDH） self-healing net, was analyzed. And a synchronization method applicable to current differential protection based on channel of optical fiber for EHV ＆ UHV long transmission line was presented, namely the method of clock correction accompanied with compensating correction by on-line calculation based on the precise line model. The error of compensation was verified less than 0.5μs by EMTP simulation. The analyses and simulation results confirm the method to be valid and feasible to keep the sampling data between two sides of the optical fiber channel synchronv for EHV ＆ UHV long transmission line.