Numerical investigation of the effect of valve reactor design on thyristor stress in a HVDC thyristor valve

The overvoltage on the thyristor elements is of particular interest for practical design. Dependence of the behavior of the overvoltage on characteristics of the anode reactor was investigated mostly by numerical simulation by transient voltage program. The point in the valve, to which the core of the anode reactor is connected, critically changes the voltage that appears on the thyristor elements. The stray capacitance of the winding to the core is another important characteristic value. A structure supported thyristor valve for DC transmission of /spl plusmn/500 kV, 2800 MW was developed with the aid of the understanding about this voltage behavior.