Typical models of compact transmission lines and application prospect in 500 kV AC system of China

Combined with the situation of 500 kV AC system of China, this paper outlines the several typical models of compact transmission lines, including single-circuit models and double-circuit models. Calculating the different arrangement of conductor lines. The parameters such as maximum surface field gradients, surge impedance, natural power transfer capacity and electromagnetic fields of compact transmission lines are calculated and also compared with traditional transmission lines based upon the operation circumstances of 500 kV AC system. By adopting the compact transmission lines, maximum surface field gradients can be reduced, and surge impedance can be decreased resulting in significantly higher natural power transfer capacity. The width of high electromagnetic field corridor is narrowed. It will contribute to gaining tremendous economic benefit and has a good prospect for application in China