Optimized parametrization of adaptive controllers for enhanced current regulation in grid‐tied converters

Abstract

SummaryGrid‐connected converters play a significant role in renewable energy systems, acting as a crucial interface between the inverter and the electrical grid, often incorporating LCL filters. One of the primary challenges in controlling grid‐injected current is the grid uncertainty, which can have a direct impact on the resonance frequency of the LCL filter. Adaptive controllers are feasible to deal with this kind of situation. However, the setup of these controllers requires an experienced designer. This work proposes a novel approach for parametrization of adaptive controllers, as well as their gain initialization, using particle swarm optimization, considering performance indexes and stability constraints. The proposed approach improves the current tracking performance and avoids relevant overshoots during transient regimes. The experimental results of current regulation in a grid‐tied voltage source inverter with an LCL filter provide compelling evidence for the effectiveness of this method. The optimized control structure exhibits significantly lower regulation errors and demonstrates improved tracking dynamics when compared to non‐optimized control structures.