厂站自动化系统中应用网络时间同步技术探讨

Discussion on application of network-based timing technology in power plant and substation automation systems

根据IEC61850标准和实际应用情况,介绍了厂站自动化系统对时间精确性的要求、对网络对时方式的需求及目前厂站自动化系统中最常见的对时实现方案,特别关注了网络对时的精度问题。结合系统保持时间的原理、网络时间协议(NTP)/简单网络时间协议(SNTP)的最新进展及其偏差定性分析和有关典型试验数据,得出以下结论:对于站控层节点机,完全可采用网络对时方式;若能在时间精确度上取得一定的改善,则有可能实现间隔层和过程层设备部分或者全部网络化对时。

The requirement of time accuracy,the demand of network-based syncnronlzauon mode and the most common time synchronization schemes in power plant and substation automation systems are presented according to the IEC 61850 standard and its practices,with the accuracy of time synchronization over Ethernet emphasized. Based on principles of timekeeping in systems, current states of NTP（Net Time Protocol） and SNTP（Simple Net Time Protocol） and their qualitative error analysis,and the typical experimental data,it is concluded that the network-based time synch scheme can be applied to the substation level host. If the time precision can be improved to a certain degree,all or most of bay level and process level equipments may apply network-based time synchronization.