架空输电线路地线多点取能的功率分布特性

Power Distribution Characteristics of Multi-point Energy Acquisition for Overhead Transmission Lines

架空输电线路地线多点取能可以为线路的全面监测提供电源保证,同时还可以有效避免传统供电方式的弊端。地线取能可行与否的关键之一在于取能功率是否足够,有必要分析各取能点的功率分布情况。文中针对典型架空输电线路,结合理论分析与EMTP-ATP程序的仿真计算对地线多点取能时各取能点的功率分布特性进行了分析计算。结果表明,距离单点接地处最远的取能负载的功率随与前面负载的距离的增加而增加,但增幅逐渐降低并趋于稳定;而前面的负载则随该距离的增加而减小,但降幅逐渐降低并趋于稳定。同时,取能负载阻抗减小时,最后一个负载电流的变化幅度增大,而前面负载的变化幅度则减小。此外,距离单点接地处较远的取能负载功率大于较近处的负载功率。但是,取能负载位于单点接地处两侧时彼此互不影响。

Multi-locations power-tapping from ground wire of overhead transmission line could provide power for comprehensive online monitoring,meanwhile effectively avoid the defects of traditional powering methods. As the key to its feasibility is whether the power is enough,it＇s necessary to analyze the power distribution of all power-tapping locations. Aiming at typical overhead transmission line,the power distribution characteristic is analyzed through both theoretic analysis and EMTP-ATP simulations. Results show that the power of the farthest power-tapping load from the grounding location of the segmented ground wire increases as the distance between the farthest load and other loads increases,with the amplitude gradually decreasing to a stable value. While for the other loads,the powers decrease as the distance increases with the amplitude gradually decreasing and tending to be stable. Meanwhile,as the load impedance decreases,the variation amplitude of the current of the farthest power-tapping load increases,and the other load decreases. The power of the farther load from the grounding location of the ground-wire is greater than that of the closer loads. Besides,for the loads which are located at the different sides of the grounding point of the ground-wire,there is no impact on each other.