基于稀疏PMU布点的广域保护全网时间同步方案

提出一种基于稀疏相量测量单元(PMU)布点的广域保护全网时间同步方案.根据通信路由对称性信息修改电网结构图,形成对时网络.提出对时网络分区方案,对任意拓扑和PMU布点形式的对时网络进行划分,划分后的子网络可归类为4种结构.结合乒乓对时法提出分区后4种结构的对时策略,并在此过程中引入时间同步校验算法.分析了同步误差越限和时钟偏移突变等特殊情况下的应对策略.算例分析表明,该方案具有实现简单、同步精度高、误差波动范围小、适应同步数字体系(SDH)光纤环网通道变化等特点,能够满足广域保护应用要求.

Whole-network time synchronization of wide-area protection based on sparse PMU placement

A whole-network time synchronization scheme based on sparse PMU(Phasor Measurement Unit) placement is proposed for the wide-area protection.A synch network is formed by modifying the power network structure according to the symmetrical characteristic of communication routes,for which,a partition scheme is proposed.The synch network with any network topology or PMU placement is partitioned and the sub-networks may be classified into four structure types.Time synch strategy based on the ping pang time synch method is presented for each structure type and a time correction algorithm is introduced into it.The corresponding tactics against the synch error violation and clock offset jump are analyzed.Case analysis shows that,the proposed scheme has simple principle,high synch precision,small error fluctuation and good adaptability to the channel switching of SDH(Synchronous Digital Hierarchy) fiber ring network,meeting the requirements of wide-area protection.