Thyristor valve for the 12-pulse converter for the 3 Gorges - Shanghai II HVDC transmission scheme

This paper presents the design of the thyristor valve for the 3 Gorges-Shanghai II 3000MW, ±500kV HVDC scheme. The thyristor valves are based on AREVA\´s H400 series valve design using 7.2kV 5" electrically-triggered thyristor technology and the scheme is the first application of the valve design for such a voltage level. Details of the valve configuration, the cooling circuit, as well as the protective strategy are presented. Detailed electrical ratings such as the steady-state and temporary overload capabilities, the fault current capability, the valve losses, as well as the valve capabilities to cope with the fault scenarios such as the loss of AC voltage are described. The thyristor valve design satisfies the requirements of the scheme.