Lightning Response on Cable Core and Sheath in Single-Circuit Underground Cable

Throughout their operational lifespan, underground cables (UGCs) encounter diverse transient phenomena, with lightning strikes being of notable concern, particularly for hybrid cable-overhead lines . Lightning impulses wield significant influence, particularly at the termination section where the underground line meets the overhead line. This study investigates the effects of lightning strikes on both the cable sheaths and the core. The study evaluates the impact of generalized formulations developed by Xue and simplified formulations developed by Pollaczek for line parameter calculations. Furthermore, the study considers the inclusion of soil parameters dependent on frequency. Two scenarios are examined: a theoretical scenario where sheaths are presumed disconnected from the ground and a more realistic scenario where sheaths are short-circuited and grounded. The results indicate that in the theoretical scenario, the percentage deviation reaches 110.7% in the cable core of phase B. Conversely, in the more realistic scenario, a maximum percentage deviation of 68.4% is observed in the sheaths when utilizing the Pollaczek formulation.