A Hybrid Control System for LC filters that couple Energy Storage Systems with AC grids

A hybrid control system for LC network filters is proposed in this paper, which enables coupling energy storage systems with the main grid suitably. The proposed control system is developed by combining both linear and predictive control approaches: particularly, the outer grid current loop is designed by means of PI regulators, whereas the intermediate capacitor voltage and the inner inductor current loops are designed in a deadbeat predictive control fashion. As a result, three nested loops have been achieved, whose performance can be set properly through dynamic decoupling and multi-rate sampling. The effectiveness of the proposed solution is verified through numerical simulations, which refer to different grid operating conditions in terms of active/reactive power exchanges.