DC overvoltage control during loss of converter in multiterminal voltage-source converter-based HVDC (M-VSC-HVDC)

Security requires that a system continues to function even when any one subsystem fails. A multiterminal HVDC system consists of N voltage-source converters (VSCs) exchanging power through a DC network. When any one converter is lost, before the surviving (N-1) converters have time to re-establish a new power balance, the excess DC power can produce voltage spikes which are destructive to the power electronic switches. The paper shows that the advanced DC voltage controller (ADCVC), which is a higher hierarchical controller, can meet the targeted voltage margin.