Overview, comparison, and extension of emergency controls against voltage instability using Inverter-Based Generators

Abstract

This paper provides a general overview of some previously reported schemes for the on-line detection and corrective emergency control of long-term voltage instability in a power system with a significant share of Inverter-Based Generators (IBGs) connected at the distribution level. Next, it proceeds to introduce new wide-area emergency controls to avoid an imminent voltage instability. Reactive support from IBGs is utilized as part of voltage stability emergency control, while in normal operation IBGs are operating at unity power factor. Results are shown for the IEEE Nordic Test System with increased IBG penetration, through feeders adapted from Hellenic Interconnected System wind farms. The newly proposed wide-area controls are compared with existing local emergency control schemes and are shown to have superior performance.