Influence of smoothing reacteor arrangement on transients of converter station for ±500kV double-circuit HVDC system

For HVDC transmission system, the smoothing reactor has two structural types; oil-immersed core reactor and air-core reactor. The former needs to concentrate installed on DC-line, and the latter can be arranged flexibly on both pole line and neutral line. According to the different arrangements of smoothing reactors, the system steady-state performance and over-voltage of converter station have some difference. In this paper, the influence of different smoothing reactor arrangements on the system steady-state performance and converter station over-voltage performance of Xiluodu-Guangdong ± 500kV double-circuit HVDC project is analyzed by using ATP/EMTP. A reasonable arrangement of smoothing reactor is proposed, which aims at both maintaining reliability and reducing costs.