Forced commutation through series voltage injection for reactive power reduction of line commutated HVDC converter terminal

This work attempts to explain reactive power consumption in a line commutated HVDC transmission system and suggests a possible solution to reduce it. A series injection strategy has been formulated using voltage-source converters and the effects have been simulated indicating a significant reduction in reactive power consumption by the converter terminal and consequently that supplied by the source. An important outcome is the fact that the suggested set of series injection devices reduces the reactive power consumption of the converter and thus would require smaller size and cost to build. This advantage becomes more significant in case of floating offshore systems which would require lighter support structures.