Study on wide-band model and voltage distribution of ±800 kV/4750 A UHVDC valves

The voltage distribution performance of high voltage DC (HVDC) converter valve is one of important research contents about its electric characteristics. It influences the reliability even cost of converter valve. However, the calculation of voltage distribution performance is affected by analysis method and the circuit model of converter valve. In this paper, the wide-band model of ±800 kV/4750 A ultra HVDC (UHVDC) converter valve was built. The results of test and simulation indicate that the model is available. Further, both the influences of power circuit parameters and stray capacitances on the voltage distribution of such a converter valve were investigated and the key factors were also summarized. They indicate that for even voltage distribution, both the design of saturable reactor and the value of stray capacitances between valve layers and earth are important.