基于优化暂态零序方向与改进首半波的综合决策选线方法

Comprehensive Decision-Making Fault Line Selection Method Based on Optimized Transient Zero Sequence Direction and Improved First Half Wave

针对现有小电流接地选线判据适应性较差、选线精度较低的问题,提出了基于优化暂态零序方向与改进首半波的综合决策选线方法,通过带通数字滤波器的设计及暂态首半波特性分析,综合利用首半波短窗、首半波长窗以及带通滤波数据窗内极性满足特性的采样点统计,确定各自相关系数,形成综合选线判据。基于该综合决策选线方法开发了对应的选线保护装置,并进行了RTDS动模测试及真型试验。结果表明,该选线方法能适应各种系统运行方式及故障条件,验证了其有效性和可靠性。

A comprehensive decision line selection method based on optimizing transient zero sequence direction and improving the first half wave is proposed to address the issues of poor adaptability and low selection accuracy of existing criteria for small current grounding.Through the design of band-pass digital filters and analysis of transient first half wave characteristics,the first half wave short window,first half wavelength window,and sampling points with polarity satisfying characteristics within the band-pass filtering data window are comprehensively utilized to determine their respective correlation coefficients,form a comprehensive criterion for line selection.Based on this comprehensive decision-making method,a corresponding line selection protection device was developed,and RTDS dynamic simulation testing and real type testing were conducted.The results indicate that the line selection method can adapt to various system operation modes and fault conditions,verifying its effectiveness and reliability.