Two-level control for fast electrical vehicle charging stations with multi flywheel energy storage system
This paper applies a hierarchical control for a fast charging station (FCS) composed of paralleled PWM rectifier and dedicated paralleled multiple flywheel energy storage systems (FESSs), in order to mitigate peak power shock on grid caused by sudden connection of electrical vehicle (EV) chargers. Distributed DC-bus signaling (DBS) and method resistive virtual impedance are employed in the power coordination of grid and flywheel converters, and a centralized secondary controller generates DC voltage correction term to adjust the local voltage set point. The control system is able to realize the power balancing and improve DC voltage regulation with low reliance on digital communication technology. Algorithm has been developed in Matlab/Simulink and compiled to real-time simulation platform dSPACE 1006. Corresponding simulation results have been reported in order to verify the validity of proposed control strategy.