摘要
在间断角原理变压器差动保护中,需要测量差动电流导数波形的间断角。在数字式保护中,如用差分代替求导将导致噪声的百分比误差随着采样频率的提高而剧增,该文对此进行了分析并提出了用分段样条函数最小二乘法来计算电流波形的导数值,以便在提高采样率的同时降低噪声误差的影响。数字仿真及动模实验数据均表明,采用该方法后,极大地抑制了噪声对间断角计算的影响,提高了间断角计算的准确度。
Dead angle of differential currents is to be measured when realizing the transformer differential protection based on the dead angle principle. In digital relay, the percentage of noise will increase rapidly with the increase of sampling rate when derivation calculus is substituted by sampled difference term. To solve this problem, a new method using fragment function integrated with the least square algorithm is proposed in this paper. Digital simulation using the data generated by ATP and dynamic simulation indicate, after adopting the new method, the influence of white noise is greatly reduced and the accuracy of the dead angle calculation is nicely improved.
出处
《继电器》
CSCD
北大核心
2004年第7期24-27,共4页
Relay
关键词
变压器差动保护
间断角
最小二乘法
分段函数
transformer differential protection
dead angle
LSA
fragment function
