Analysis of the Cable Firing System for HVDC Thyristor Values

The firing of a HVDC thyristor valve, where several hundred thyristors are interconnected in a series-parallel combination, presents a number of fundamental problems related to the generation, transmission and reshaping of the signal. This paper presents an analysis of these problems and proposes a cable firing system suitable for HVDC thyristor valves. A calculation method of evaluating the system performance and an optimization of the system parameters are given. Also, experimental results are presented which show the actual performance of the proposed firing system on a 150-kV, 600 A thyristor valve.