交流输电线路杆塔侧的电势能采集可行性研究

Feasibility Study on Energy Harvesting Around AC Transmission Line Based on Electric Potential

基于电容式电势能采集器采集交流输电杆塔周围空间的电势能,为安装于杆塔上的输电线路在线监测装置供电.文中首先分析了电容式电势能采集的电路模型和负载阻值对采集器输出功率的影响,得到了获取最大能量的条件.然后针对交流双回500 k V干字型输电杆塔的塔头电场分布情况进行了数值仿真,得到电势能采集器适合的安装位置.最后通过实验测量到直径40 cm、间距15 cm的电容式采集器在电场发生单元工频电压为50 k V时,24 s内采集的能量为5 m J,可以等效为208#W的输出功率,满足无线传感器的最小功率要求.实际的架空输电线路运行电压更高,如能在杆塔上有效利用高场强区域,优化电容采集器结构,则完全可能实现更高的功率输出,并最终为安装于杆塔上的在线监测装置供电.

Proposed in this paper is a method of utilizing a capacitive transducer to harvest the electric potential energy stored in the space around the AC transmission line, which helps to supply power to the on-line -monitoring system installed on a transmission tower. First, the circuit model of the potential energy-harvesting system and the relationship between the load resistance and the output power are analyzed, and a way to harvesting the maximum energy is presented. Then, the electric field distribution at the tower head of a 500 kV AC double-loop transmission line is simulated, and the places suitable for transducer installation are determined. Finally, an experiment is con- ducted by adopting a capacitive transducer with a radius of 40 cm and an interval of 15 cm, and about 5 mJ of energy is obtained at 50 kV in 24 s, which means that the capacitive transducer can afford an output power of 208μW to meet the minimum power limit of wireless sensor nodes. In practically application, there is higher operating voltage compared with the experiment, by utilizing the high-intensity electric field efficiently on the tower with optimized capacitive transducer, enough energy will be harvested to power the on-line - monitoring system.