Design of the mica hydroelectric projectߞA major 500 kV SF6installation

The Mica hydroelectric project on the B. C. Hydro system is a six unit 2600 MW underground powerplant designed for unattended operation. The paper describes the basic design of the electrical features of the project including the main and station service single lines and the protection and control methods adopted. Special emphasis is placed on the power equipment aspects and the extensive use of a 500 kV Compressed Gas Insulated (CGI) bus and switchgear system to connect the underground transformers to the surface transmission lines.