三侧同杆双回线互联的T型线路测距新方法

根据同杆双回线的特性建立了同杆双回线构成的T型线路的反序正序网络,提出了基于反序正序电流的故障测距方法。在双T型线路中,反序正序网络的电气量具有完整的T字型线路的正序电气量的特点,该特点可以用来故障测距。当双T线路发生故障时,由故障支路的母线处的电气量计算到故障点的反序正序电压等于由支接点T的等值反序正序电气量计算到故障点的反序正序电压,利用反序正序电压在故障点相等的等量关系可以进行精确故障测距。大量的EMTP仿真结果表明,所给出的故障测距方案是准确的,并且在由同杆双回线构成的T型线路故障测距中显示出较大的优势。该测距方法的精度不受故障支路、故障类型、系统运行方式、故障点过渡电阻等因素的影响。

Fault locating algorithm for T-type lines with parallel transmission lines on same pole at three sides

The inverted positive sequence network is built according to the characteristic of the parallel transmission lines on the same pole,and the accurate fault locating method based on the inverted positive sequence current is proposed.The electrical measurements of the inverted positive sequence network of parallel T-type lines have the complete characteristics of the electrical measure-ments of the positive sequence network of single T-type line,which are used to locate the fault.When fault occurs on parallel T-type lines,the inverted positive sequence voltage of the fault point calculated by the electrical measurements of the faulty branch bus is equal to that calculated by the equivalent inverted positive sequence electrical measurements of node T,based on which,the fault is precisely located.EMTP simulations indicate that this fault locating algorithm is correct and more suitable for T-type lines with parallel transmission lines on same pole.Its precision is not affected by the factors of faulty branch,fault type,system operating mode and transition resistance.