同塔交直流线路容性耦合干扰的分析与计算

超(特)高压交直流同塔多回输电技术在解决输电走廊占地问题中的应用已经得到关注与研究,因此文中研究了交直流同塔的容性耦合干扰以及屏蔽措施。首先建立了单回和双回交流线路分别于直流线路同塔时,交直流线路的容性耦合干扰分析模型,分别计算了不同结构的交流线路在同塔并行的直流线路上产生的容性耦合感应电压。仿真结果表明:交流线路的排列方式、交直流垂直线间距和交流线路相导线的相序排列对容性耦合感应都有影响。感应电压值随垂直间距的增加呈非线性递减;双回交流线路逆向排序可以抑制感应电压,其中鼓型逆相排序可以使交流线路在直流线路中的感应电压值降低46.8%。同时,增加接地线也可以使感应电压值下降7%~18%。

Analysis and Calculation for the Capacitive Coupling of the AC and DC Transmission Lines on One Tower

More and more attentions were concentrated on the development of ultra-high voltage(UHV) transmission line techniques.To solve the land occupation,building the UHV AC and DC transmission lines in the same tower is investigated by some experts.In this paper the capacitive coupling interference between the AC and DC transmission lines is calculated when they are erected in the same tower,the interference for different situation is analyzed,and based on the interference,measures to shield the interference are presented in the end.Results indicate that the induced voltage in the DC transmission lines depends on the arrangement of AC transmission lines,the vertical distance between the AC and DC transmission lines and phase of three phase AC have influence on the capacitive coupling effects.The induced voltage decreases with the increase of the distance.To restrain the induced voltage on the DC transmission lines the anti-phase of double circuit technique can be adopted.By using drum arrangement in the AC transmission lines,the induced voltage on the DC transmission lines can be decreased by 46.8%,and using ground wire can decrease the induced voltage by 7%~18%.