Study on the mechanical characteristics of pumped storage cable laid in serpentine

Abstract

The operating environment of pumped storage power stations, characterized by high drop, steep slopes, and frequent load fluctuations, makes it difficult for high-voltage cables to effectively release the thermal expansion and mechanical stress they bear. This paper focuses on the thermal-mechanical stress problem of 500 kV cross-linked polyethylene (XLPE) cables in pumped storage power stations and systematically explores the temperature field distribution of the serpentine-laid high-voltage cables under the highest heat load, the stress release mechanism of the serpentine laying, and the contact stress characteristics at the serpentine arc top. A theoretical framework for calculating the cable thermal expansion based on quadratic function fitting of the serpentine curve and the contact model between the corrugated aluminum sheath and the buffer layer is established. Through finite element analysis, the thermal-structural effects are simulated, and two-dimensional and three-dimensional models are used to simulate the horizontal and vertical laying configurations. This research provides important theoretical guidance for the design and installation of cables under complex operating conditions of pumped storage power stations.