利用电流模型识别的输电线路纵联保护新原理  

A Novel Transmission Line Pilot Protection Principle Based on Current Model Recognition

作　　者：索南加乐[1] 马超[1] 康小宁[1] 王晨清[1] 刘鑫[1] 李宗朋[1] 

机构地区：[1]西安交通大学电气工程学院,陕西省西安市710049

出　　处：《中国电机工程学报》2012年第19期109-116,193,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51037005;51177127);国家重点基础研究发展计划项目(973项目)(2009CB219704)~~

摘　　要：针对纵联电流差动保护应用于超特高压长线时受分布电容影响性能降低这一问题,基于矩阵束算法能够分析暂态电流组成的特点,提出一种仅用电流量的适用于分布参数输电线路的纵联保护新原理。该原理采用模型识别的思想,首先推导出线路故障时两侧电流故障分量之和与之差比值的理论表达式,作为待识别的基准模型。进而定义模型误差函数用于刻画实际故障数据与基准模型的符合程度。区外故障时,故障数据符合基准模型,模型误差为0;区内故障时,故障数据不符合基准模型,模型误差不为0,据此区分外部和内部故障。该原理不受分布电容影响,无需补偿电容电流;充分利用故障电流信息,无需滤波;能够灵敏快速地动作。用ATP仿真和动模仿真验证新原理的有效性。Due to the distributed capacitance, the performance of current differential pilot protection will deteriorate when applied to ultra/extra high voltage long transmission lines. Considering matrix pencil algorithm can analyze the composition of transient currents, a novel pilot protection principle using only current data was proposed which can be applied to distributed parameter transmission lines. This principle adopted model recognition concept. Firstly, the theoretical expression was derived which described the ratio between the sum and difference of two terminal fault component currents, and the expression was treated as the standard model. Then the model error function was defined while the function measured the extent to which actual fault data accorded with the standard model. When an external fault occurs, fault data correspond with the standard model and model error equals zero. When an internal fault occurs, fault data do not correspond with the standard model and model error does not equal zero. Therefore, external fault and internal fault are distinguished. This principle is immune to the distributed capacitance and it is unnecessary to compensate the capacitive cu~＇rent. Besides, fault current data are fully used and filter becomes unnecessary. Moreover, fast operation speed and high sensitivity can be attained. Both ATP simulation results and dynamic simulation results show that the proposed principle is effective and reliable.

关 键 词：纵联保护 分布电容电流 矩阵束算法 模型识别 

分 类 号：TM77[电气工程—电力系统及自动化]