单回及同塔双回交流输电线路参数测量理论

A Parameter Measurement Theory of Single and Double Circuit AC Transmission Lines

为获取单回或同塔双回交流输电线路的对地电容、双回线路各相之间的耦合电感和耦合电容等测量数据,文中建立了全新的单导线大地返回电路的分布参数模型及其测量方法;提出了三相对称参数的单回交流线路电报方程解耦成零序和正序分量的方法。此外,双回三相线路之间的耦合参数可以通过两相系统的序分解进行解耦。基于上述分析,通过同塔双回线路在3种组合方式(单回线路三相正序电路、双回线路组成的两相正序电路、双回线路组成的零序电路)下的开路阻抗和短路阻抗测量结果,应用本文的理论模型可以精确地求解出各分布参数。该文构建了单回线路和同塔双回交流输电线路分布参数的理论基础。

In order to obtain ground capacitances, mutual inductances and coupling capacitances of single AC line or the double circuit AC lines on a same tower, an improved model with distributed parameters and measurement method had been firstly established for a single conductor ground return line. Then, Telegrapher equations for symmetrical three phase lines were decoupled as positive and zero sequence circuits and the measurements were carried out on sequence circuits to calculate the distributed parameters. Furthermore, the coupling parameters between double circuit AC lines could be decoupled by sequence analysis of two phase systems. Based on the theoretical analysis, and by open circuit and short circuit impedance measurements of double circuit lines in three circuit modes including positive sequence circuit of a single line, positive sequence circuit of two phase systems composited by double lines and zero sequence circuit of double lines, all the parameters such as inductances and capacitances to ground of each conductor, and coupling capacitances as well as mutual inductances can all be solved by the presented method. The paper constitutes a basic theory to measure the distributed parameters of single AC line, and further the double circuit AC lines on a same tower.