摘要
冲击接地阻抗是影响输电线路防雷等级和雷击跳闸率的重要因素。目前,通常采用模拟试验或者仿真计算来研究冲击接地阻抗,无法真实反映接地体冲击接地特性。为了研究接地体在冲击电流下的特性,本文采用大型冲击电流发生器对接地体进行真型试验研究,以多种型式接地体为研究对象,讨论了冲击电流幅值和接地极尺寸对接地体冲击特性的影响并建立了接地体冲击接地阻抗EMTP仿真模型。试验结果表明,冲击电流幅值升高、接地体长度增加或截面直径增大都会使冲击接地阻抗降低,且接地体长度和冲击电流幅值的影响均出现饱和现象;仿真结果表明,通过分段π型等值电路Models模型建立的接地体冲击接地阻抗仿真模型可有效计算接地体冲击接地阻抗。
Impulse grounding impedance is a significant factor which affects the level of lightning protection and lightning trip-out rate of transmission lines.At present,the simulation method or reduced-scale experiment is often used to study impulse grounding impedance characteristics,however it could not obtain the real situations.It is important to use full-scale experiment to get impulse grounding impedance characteristics of the grounding electrode.Various forms of grounding electrode were chosen as research object in this paper,discussing the effect on the impulse characteristics of grounding electrode,such as impulse current amplitude and size of grounding electrode.EMTP simulation model of impulse grounding impedance of grounding electrode was established.When the amplitude of impulse current increases,the length of grounding electrode increases or the cross-section diameter increases,the impulse grounding impedance will decrease,and the influence of the length of grounding electrode and the amplitude of impulse current will be lead to saturated.The simulation results show that the simulation model of impulse grounding impedance of grounding electrode based on the model of piecewise π equivalent circuit can effectively calculate the impulse grounding impedance of grounding electrode.
作者
高峰
刘阳
郭洁
张健
王荆
李英奇
GAO Feng;LIU Yang;GUO Jie;ZHANG Jian;WANG Jing;LI Yingqi(Research Institute of State Grid Shaanxi Electric Power Company,Xi’an 710049,China;Xi’an Jiaotong University,Xi’an 710049,China;State Grid Shaanxi Electric Power Company Xi’an Power Supply Company,Xi’an 710048,China;State Grid Shaaxi Electric Power Company,Xi’an 710048,China)
出处
《高压电器》
CAS
CSCD
北大核心
2020年第4期148-152,158,共6页
High Voltage Apparatus
关键词
接地体
真型试验
电感效应
火花效应
仿真模型
grounding electrode
full-scale experiment
inductance effect
spark effect
simulation model
