Research on Arrester Protection Scheme of Converter Station for ± 800 kV UHV DC Project From Jiuquan to Hunan

This paper introduces a new arrester protection scheme of converter station for ±800 kV UHV DC project from Jiuquan to Hunan. The new scheme proposes to use A2 arrester directly at the AC side of the maximum potential converter transformer and use CB1A and CB1B arrester at the bus between two 12 pulse converter units. The new scheme proposes to install smooth reactors equally on pole bus and 400kV DC bus and abandon E1H arrester. This paper proposes to install CB1A arrester, CB1B arrester and smooth reactors together outdoors in order to save more space for valve hall. This paper compares the traditional typical scheme (scheme A) for ±800kV UHV DC converter station and the new scheme (scheme B) and analyzes the characteristics and advantages of the new scheme. This paper also selects the arrester parameters according to the selection principle of arrester DC reference voltage. The new arrester protection scheme and its parameters play some guiding roles in ±800kV UHV DC project from Jiuquan to Hunan.