基于电流向量l_(2)范数的变压器比率差动保护新判据  

New Criterion of Transformer Ratio Differential Protection Based on l_(2) Norm of Current Vectors

作　　者：廖小君 李龙源[1] 童晓阳[1] 王晓茹[1] LIAO Xiaojun;LI Longyuan;TONG Xiaoyang;WANG Xiaoru(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 611756,Sichuan Province,China)

机构地区：[1]西南交通大学电气工程学院,四川省成都市611756

出　　处：《中国电机工程学报》2022年第18期6693-6703,共11页Proceedings of the CSEE

摘　　要：为提升比率制动差动保护区内故障的灵敏性和区外故障抗TA饱和能力,提出一种基于电流向量l_(2)范数的变压器比率制动差动保护新判据。首先,对变压器区内外故障时电流信号进行范数分析,利用范数边界变化特点,构建一种基于电流相量差的电流向量l_(2)范数的制动电流。其次,利用电流向量l_(1)范数和l_(∞)范数的边界约束关系对l_(2)范数制动电流进行优化。在保证区内故障灵敏度同时,进一步提升l_(2)范数比率制动差动保护的抗饱和能力。最后,经RTDS测试和工程实际案例,证明提出的新判据具有更高的灵敏度、更强的抗TA饱和能力,综合性能显著优于当前工程广泛采用的电流模值和制动及最大值制动方法。To enhance the sensitivity at the inner fault and the TA anti-saturation capability at the external fault of the transformer ratio restrained differential protection,a new criterion based on l_(2) norm of current vectors was proposed in this paper.Firstly,the norm analysis of the current signal at the inner and external faults of the transformer was performed.A restraint current based on l_(2) norm of current vectors composed of current phasor difference was constructed by using the characteristics of the change of norm boundary.Secondly,the l_(2) norm based restraint current was optimized using the boundary constraint relationship of the l_(1) norm and the l_(∞)norm so that the sensitivity can be kept and its TA anti-saturation capability can be further improved.Finally,the RTDS testing and engineering practical cases prove that the proposed criterion has higher sensitivity and stronger TA anti-saturation capability.The comprehensive performance of new criterion is significantly better than the absolute value sum restrained and the maximum value restrained methods widely used in engineering.

关 键 词：变压器差动保护 比率制动特性 范数理论 电流互感器饱和 

分 类 号：TM77[电气工程—电力系统及自动化]