HV networks and substations

Abstract

High-voltage systems provide a link between major transmission and medium voltage distribution systems. In addition, medium-sized power stations are connected into these HV networks. Many HV systems now operating primarily as distribution networks have earlier been used for transmission purposes until superseded by higher-voltage systems. High-voltage switching stations provide suitable node points for adjusting network configurations for system-operation purposes, and often are focal points for HV/MV transformation supplying the MV systems. Standardised layouts have tended to be adopted. These include singleand multi-busbar arrangements, often involving large open-air layouts or low-volume metal-clad switchgear in purpose-designed buildings. The trend is for enclosed construction requiring less space, often utilising simpler busbar layouts than the more conventional open-air arrangements.