中文摘要：

为解决变电站采样值（SAV）报文容易发生延迟或丢失的问题，提出了一种基于自适应丢包的SAV报文估计算法。针对SAV报文的传输特点，应用拉格朗日插值算法，重点研究了二次SAV报文估计算法的实现流程与同步插值时刻选取方法。利用PSCAD中得到的单相接地故障仿真实验数据，通过MATLAB软件对SAV报文估计算法的估计准确度进行了验证，并对估计误差进行了详细分析。结果表明，应用该算法对多个SAV报文估计具有较高的准确度。因此，将该算法嵌入到常规继电保护算法中，可以有效解决SAV报文发生延迟或丢失带来的安全隐患，有利于维持变电站的稳定、可靠运行。

英文摘要：

In order to solve the problem of delayed or lost sampled value （SAV） in substation, a self-adaption packet-loss-based SAV estimation algorithm is proposed. According to the transmission characteristics of SAV and applying Lagrange, the realization flow chart of the quadratic SAV estimation algorithm and selection method for synchronous interpolation time are especially studied. With experimental data obtained from single-phase grounding fault simulation in PSCAD, the estimation accuracy of the algorithm is confirmed By MATLAB software. Especially, the estimation error is analyzed in detail. Research results show that this algorithm has high estimation accuracy for several SAV estimation. Therefore, embedding this algorithm in normal relaying algorithm can be very useful to solve the hidden danger caused by delayed or lost sampled values, which is in favor of stable and reliable operation of substation.