Utilizing Synchrophasor-Based Protection Systems with VSC-HVDC Controls to Mitigate Voltage Instability

This article rationalizes the need of coordination between protective systems and VSC-HVDC controls to steer power systems away from voltage instability conditions. The concept of coordination involves the use of feasible communication mechanisms which can be exploited by protection systems to send out a "protective information set" to an algorithm which will determine preventive, corrective, and protective actions particularly by taking advantage of the availability of VSC-HVDC. This "protective information set" considers synchrophasor vector processing capabilities which allows for the exploitation of phasor measurements while satisfying protective relaying data transmission and processing requirements. Coordination refers to the ability of the protective systems and VSC-HVDCs to cooperate and to synchronize their actions so that voltage instability can be avoided.