A Flying Spots Detection and Recovery Scheme Based on Hybrid-Waveform Recognition Method

Flying plots detection has been the focus of relay protection in power system for a long time. With the promotion of Smart substation in our country, the number of SV devices is greatly increased. Abnormal data (flying plot) caused by sampling device itself has brought tremendous pressure to the power system. The traditional flying plot detection algorithm has plenty of defects, such as low pertinence, low sensitivity and long sampling period. This paper proposes a new algorithm to identify flying plot by analyzing the wave form characteristics of sampling data. The traditional waveform recognition methods are combined in this algorithm. It has the concept of standard wave window and can distinguish flying plot in a short time. In addition, sine recovery algorithm is used to recover the flying plot. This paper uses PSCAD software to verify the validity of this algorithm. Simulation results show that the proposed method has high reliability.

基于复合波形识别算法的“飞点”检测和还原方案研究

智能变电站以全站信息的数字化为基本要求,利用数字采样代替传统的模拟采样,采样装置数量大大增加。站域保护对数字采样的可靠性提出了更高要求,而SV(采样值)中存在大幅值“飞点”(数据异常点)是引起保护误动的主要原因。在深入研究“飞点”产生原因及其特征的基础上,提出一种基于复合波形识别算法的“飞点”检测和还原方案:采用基于积分型波形对称法和导数型波形识别法的复合波形识别算法,利用标准正弦波窗的概念,能迅速、准确地识别“飞点”数据。另外,根据正弦恢复算法可对“飞点”数据进行修复,无需闭锁判据即可保证保护的可靠性。通过建立PSCAD仿真模型,模拟单个“飞点”和连续“飞点”的正常运行和短路故障时波形,验证了所提“飞点”识别及修复方案的可靠性。仿真结果证明,保护装置动作正常,不会发生误动、拒动。