220kV变电站GPS时间同步系统实现技术

Implementation of GPS synchronization system in 220 kV substation

基于220 kV变电站全球定位系统(GPS)时间同步系统项目的实施经验,总结了实现时间同步系统需要考虑的关键技术和问题,主要从对时设计、运行监测、对时校验、对时误差等进行了分析探讨。要求在变电站内实现GPS统一对时,给出了一个典型的站内设备对时架构图,设计了单主钟和冗余互备等3种GPS时钟架构设计模式,并加以说明。为实现站内对时的运行监测,设计了基于时脉冲事件顺序记录的分析方法来计算对时误差。站内对时校验应依据GPS校验仪进行,介绍了校验原理和相应校验方法,并分析影响校验精度的主要因素。对站内对时误差出现的常见原因和解决方法进行了分析介绍,并针对软、硬协同对时误差问题提出了一种基于公式化分析的误差定量分析方法。

The key techniques in the implementation of 220 kV substation GPS（Global Positioning System） synchronization system are summarized,mainly in design,monitoring,verification and error analysis. A typical architecture of time synchronization system for substation devices is presented,as well as three configurations of GPS clocks：single,double and multiple. The synchronization error is calculated based on the on-line analysis of PPH （Pulse Per Hour） SOE （Sequence Of Events） for synchronization monitoring. Time accuracy verification is carried out with GPS verification instrument. Its working principle and verification method are presented and its main influencing factors are introduced. The causes of synchronization error are summarized and the countermeasures are proposed. A quantitative analytical method of synchronization error is presented for software-hardware coordinating synchronization.