areaPower system dynamics: modelling, stability, security and control.
currentlyConsultant to transmission system operators.
Adviser on research projects.
formerlyResearch Director at the Fund for Scientific Research (FNRS)
Adjunct Professor at the Dept. of Electrical Eng. and Comp. Sc. (Montefiore Institute)
of the University of Liège
phone +32 494 06 33 73
this page

I have 42 years of research activities in the field of electric power system engineering with a strong involvement in collaborations with industry (mainly transmission and distribution system operators) and other universities in Europe.

The overall theme of my work is the dynamics of large power systems, more precisely their modelling, stability, security and control. My most recent research topics:

  • Time-domain simulation of large-scale power systems. Fast, simplified simulation of long-term dynamics. Application to voltage stability analysis and control, Shared-memory parallel processing of detailed time-domain simulation under the phasor approximation. Co-simulation of electromagnetic transients and phasor models.
  • Corrective control in emergencies. Early detection of a system evolving towards instability and automatic remedial actions. Application to voltage instability.
  • System monitoring and state estimation. Combined used of SCADA and PMU measurements to track the changing network operating point.
  • High Voltage Direct Current (HVDC) systems using Voltage Source Converters (VSCs). Modelling and control of VSCs. AC system frequency support from HVDC links or grids. Control of future multi-terminal HVDC grids. Control of future offshore wind power hubs (energy islands with low or zero inertia: See the multiDC project)
  • Active distribution networks hosting Inverter-Based Generators (IBGs). Control of dispersed IBGs at distribution level to support or stabilize transmission system voltages. Coordinated control of dispersed IBGs to correct abnormal voltages and clear contingencies in the distribution grid. Impact of IBG control on short-term voltage dynamics. Dynamic equivalents of active distribution networks for use in large-disturbance dynamic simulations of the transmission system.

Salient collaborations with industry and academia :

  • Development, validation and implementation of ASTRE, a voltage stability and security analysis software: with RTE (France), Hydro-Québec (TransEnergie division and IREQ, Canada), IPTO (Greece, within the OMASES project financed by European Union).
  • Voltage stability and security studies: for ELIA (Belgium), Amprion (Germany).
  • Development and testing of the RAMSES software with Hydro-Québec (TransEnergie division and IREQ).
  • Research on Control of multiterminal HVDC grids and Dynamic equivalents of active distribution networks supported by the R&D dept. of RTE.
  • Domain decompostion methods in dynamic simulations: with RTE and Tractebel Engineering (within the PEGASE project financed by European Union).
  • ORES and RESA (Belgian distribution system operators) within the GREDOR project financed by Walloon region.

On the academic side, I have long-standing collaborations with the teams of Prof. Costas Vournas, National Technical University of Athens (Greece) and Prof. Xavier Guillaud, Ecole Centrale de Lille-L2EP (France).

Other activities

I have contributed (and I still do so) to various Working Groups and Tasks Forces of IEEE Power and Energy Society (PES), CIGRE and CIRED.

I have been active in the Power System Dynamic Performance (PSDP) Committee of the IEEE PES, which I served as Secretary, Vice-Chair and Chair from 2009 to 2014. I also served as Editor of the IEEE Transactions on Power Systems from 2005 to 2008.

I have been a member of the scientific committees of various conferences (PSCC, IEEE PowerTech, IREP, etc.) and advisory boards of international projects.

Besides the courses that I taught at the University of Liège (click here for more details), I gave lectures at various universities (Ecole Centrale de Lille, Manchester, Seville, Pontif. Com. Madrid, etc.), tutorials at conferences (PSCC, IEEE PES general meetings, IEEE ISGT, etc.). I also gave in-house courses at Hydro-Québec and I was instructor in a few EES-UETP courses.


I was very honoured being elevated Fellow of the IEEE for Contributions to voltage security analysis and control (2005), receiving the André Blondel Medal from SEE (France, 1997) and the Adolphe Wetrems prize from Royal Academy of Belgium in 1995.

More recently, it was a true pleasure and honour to have my contributions recognized through the 2022 IEEE PES Prabha S. Kundur Power System Dynamics and Control Award of the IEEE Power and Energy Society for fundamental contributions to voltage security analysis, protection and control.

Some of my publications were awarded (Prize paper award of the IEEE PES PSDP Committee in 2017, 2011 and 2005, best paper award at 8th IFAC Symp. on Power Plant & Power System Control in 2012, etc.). Some of my PhD students were awarded for their papers and presentations (B. Papadias award for high-quality student paper at IEEE PES PowerTech conferences in 2015, 2013, 2009 and 2007, best student paper at CIGRE conference in 2014 and IEEE PES General Meeting in 2014) or for their theses under my supervision (AIM prizes for the best thesis in 2019 and 2021).