Universidad Pontificia Comillas. Madrid (Spain)
April 8th, 2024
Summary:
The aim of this thesis is to investigate supplementary control strategies in Grid-forming voltage source converters (GFM-VSCs) to improve transient stability in power systems with 100% non-synchronous generation.
With the increasing integration of non-synchronous generation sources, stability becomes challenging due to the fast dynamics of the voltage source converters (VSCs). This scenario poses a significant challenge to power system stability, particularly transient stability. The study proposes control strategies based on active- and voltage/reactive-power control in GFM-VSC for transient stability improvement.
This thesis compares various self-synchronisation mechanisms of GFM-VSCs under different scenarios, analysing their impact on transient stability. Moreover, two proposed Fast Voltage Booster (FVB) strategies based on voltage/reactive-power controls aim to enhance transient stability by adjusting the voltage set-point without significant changes to primary energy source set-points. One control strategy (FVB-L) uses local measurements, while the other (FVB-WACS) uses global measurements of the frequency of the centre of inertia (COI). The thesis also analyses the impact of FVBs when employing different current limiters (current saturation algorithms and hybrid current limiters) in GFM-VSC-based generators. Additionally, a local active-power control strategy (TSP-L) is introduced and compared with two existing control strategies from the literature, aiming to further improve transient stability in power systems with 100% non-synchronous generators.
The use of GFM-VSCs in these types of systems creates a need for control strategies that can improve transient stability. Therefore, this thesis aims to address this need by analysing the transient stability of power systems with 100% non-synchronous generation and proposing control strategies based on active- and voltage/reactive-power control in GFVSC for transient stability improvement.
Spanish layman's summary:
La tesis aborda el diseño de controles de generadores basados en grid-forming (GFM-VSC) para la mejora de la estabilidad transitoria en sistemas de potencia con 100% de generación no síncrona. Los resultados confirman la eficacia de los controles propuestos en la mejora de la estabilidad del sistema.
English layman's summary:
The thesis aims at the control design for grid-forming VSC-based generators (GFM-VSC) to improve transient stability in power systems with 100% non-synchronous generation. Results confirm the effectiveness of these proposed controllers in improving the system's stability.
Descriptors: Electrical technology and engineering, Power generation
Keywords: Voltage source converter, VSC, Grid forming, Transient stability
Citation:
R. Ávila-Martínez (2024), Control of grid-forming vsc-based generators to improve transient stability in power systems with100% non-synchronous generation. Universidad Pontificia Comillas. Madrid (Spain).
