Analysis of Sheath Grounding and Protection Mechanisms in 110 kV Cables

With the continuous expansion of power systems and increasing demand for supply reliability, the significance of sheath grounding in 110 kV cable lines has become more prominent. This study investigates the grounding schemes and protection mechanisms for 110 kV cable sheaths, analyzing the characteristics and applications of direct grounding, cross-bonding, and other methods. Research shows that proper grounding can effectively suppress sheath voltage rise and prevent insulation breakdown. By evaluating existing sheath grounding devices, the critical functions of overcurrent protection and loss-of-phase protection in achieving voltage equalization are demonstrated. This paper also discusses the impact of faulty grounding on electrical safety, identifies limitations in current protection mechanisms, and proposes optimization measures, providing a theoretical basis for enhancing the reliability of 110 kV cable systems.