基于锁相环技术的数字化变电站采样系统同步方案

A Synchronization Scheme of the Sampling System in Digital Substation Based on Software Phase-Locked-Loop Technology

为解决数字化变电站系统中的分布式采样同步性问题,提出利用软件锁相环技术,通过修正不同设备之间的相位和频率的偏差,实现采样同步。根据变电站的实际情况,给出了具体的实现方案。并以基于电子式互感器的母线保护装置和光纤纵差保护两个例子,给出了软件锁相环技术的仿真和应用效果。证明了软件锁相环技术在成本和可靠性方面的优势。

A software phase-locked-loop （PLL） algorithm is propsed to solve synchroziton problem in distributed sampling for digital substation system. By correcting deviation of frequency and phase among different devices through PLL algorithm, sampling synchrozation can be achieved. The principle of PLL technology and realizing method are also given in this paper with simulation and application of two feasible examples： busbar protection based on electronic transformer, and optical fibre line differential protection. Advantages in cost and reliability of PLL algorithm is proved.