Model-Free Adaptive Cooperative Control Strategy of Multiple Electric Springs: A Hierarchical Approach for EV-Integrated AC Micro-Grid

With the aim of addressing the power quality problem associated with voltage fluctuation of multiple electric vehicles and renewable energy generation equipment integration into the AC micro-grid, a multi-agent system-based model-free adaptive constrained control method is proposed in this paper. First, a novel hierarchical control structure is developed. Therein, the upper-level cooperative controller is designed based on the directed graph and droop control strategy, enabling efficient power distribution among multiple electric vehicles. For the lower-level voltage controller, a model-free adaptive constrained control strategy is designed, incorporating a pseudo-partial derivative-based output observer, and an anti-windup compensator is designed to solve the voltage fluctuation problem, which achieves precise tracking of each electric spring output voltage. Finally, the effectiveness and superiority of the proposed control strategy is verified by the MATLAB/Simulink platform under scenarios of grid-side voltage fluctuations and load variations.