Study on reactive control strategy of UHVDC transmission project

To keep normal running of UHVDC in addition to the active control reactive power control were needed to maintain a normal commutation voltage of converter valve. Reactive power control need coordinate with priority of each level control when considering filtering and voltage stability. Traditional reactive power and voltage control does not generally consider the priority issues of reactive power control. In order to analysis the mechanism of reactive power and voltage control of UHVDC. Take the ±800kV Jinsu UHVDC as background, based on the study on the filter configuration, detailed analysis of the relationship between the priority of the five control levels for reactive and voltage control as well as the its control principles were make. Research results indicates that the reactive power control strategies of UHVDC have five levels as abs min filter control, Umax/Umin control, Qmax control, min filter control and U/Q control under priority from low to high.