Name: Alejandro Bayo Salas


KU Leuven

Promotor / Supervisor

Promotor: Prof. dr. ir. Dirk Van Hertem

Copromotor: Prof. dr. Jef Beerten & Dr. Johan Rimez, Elia Engineering

Samenvatting van het onderzoek / Summary of Research

Power systems are experiencing the most profound changes driven by the integration of renewable generation. In addition to the new generation, HVDC  transmission lines are being installed in order to increase the network capacity and allow the control of power flows. Both previous components use a power electronic converter as an interface. These converters present faster dynamics compared to conventional installations and it is uncertain how the interaction between multiple converters installed in the vicinity  could influence the overall system stability. Indeed, the interoperability of a system with massive amounts of converters is regarded as a key issue in future power systems.  Already, during the first stage of the integration of power electronics in the grid, several stability problems have occured at unexpected frequencies.

This research aims at studying this new type of stability problem in power systems with multiple converters. The study demonstrates the limitations of previous representations of components in capturing the dynamics which impact the new type of instability. Based on these observations, new methodologies to address the power system stability in networks with multiple converters are proposed as well as the necessary network representations to capture the actual dynamics.

One of the main challenges to control and avoid this type of instabilities is the variation and uncertainty of resonances in a network. Indeed, an accurate representation of resonances and network dynamics is extremely difficult due to the variation of the grid topology and the uncertainty in the modelling of several network components. To overcome this, new controllers are designed in order to mitigate the experienced instabilities considering several changes in the network topology of a grid and the frequencies at which the instabilities are estimated to occur.

Volledige tekst van het doctoraat / full text

Examencommissie / Board of examiners

Prof. dr. ir. Dirk Van Hertem (promotor) 
Prof. dr. Jef Beerten (copromotor) 
Dr. Johan Rimez (copromotor) , Elia Engineering 
Prof. dr. ir. Paul Van Houtte (voorzitter/chairman) 
Prof. dr. Panagiotis Patrinos (secretaris/secretary) 
Prof. dr. ir. Ronnie Belmans 
De heer Koenraad Van Reusel 
Prof. dr. Carlos Ugalde-Loo , Cardiff University 
Dr.Ir. Lukasz Kocewiak , DONG Energy Wind Power