Recent work

Real-time, measurement-based identification of voltage stability

A lecture given by Emeritus Professor Costas Vournas at University College Dublin in May 2026, as part of the IEEE PES Distinguished Lecturer Program.

It sets out why on-line stability monitoring is needed alongside security assessment, introduces the NLI and RLI indices, tests them on the IEEE Nordic system and on a replay of the 2004 Athens blackout, and closes with the monitoring application running at the Hellenic national control centre and its performance during an incident on the Crete interconnection.

Implementation of real-time, PMU-based, long-term voltage stability monitoring

PS ARTS ran a project to develop a software tool, installed in the control centre of the Hellenic Interconnected System, which indicates proximity to instability using synchronised phasor measurements taken from a sparse set of PMUs.

The work was presented at the Protection, Automation and Control World Conference in Athens in June 2024. The presentation covered the structure of the application, its interface and its filtering, with indicative results following an actual system incident.

Long-term voltage stability wide-area control using PMU measurements

A presentation at the 2022 IEEE PES General Meeting on voltage stability wide-area control using PMU measurements together with online voltage instability indices: the PMU-based NLI and the relay-based RLI. Both indices are among the main products PS ARTS provides.

Voltage stability support by wind farms

A keynote speech given by Emeritus Professor Costas Vournas at the IEEE PES Transmission and Distribution Conference and Exposition, Latin America.