Adaptive TS Fuzzy-Based MPC for DC Microgrids With Dynamic CPLs: Nonlinear Power Observer Approach

Abstract

The performance of a DC microgrid (MG) might degrade because of the dynamics of constant power loads (CPLs). In this paper, a novel adaptive controller is proposed to mitigate the destructive effect of time-varying uncertain CPLs. A nonlinear disturbance observer is developed to estimate the instantaneous power of the CPLs. The estimated CPLs powers are then employed in a Takagi–Sugeno fuzzy-based model predictive control strategy, aiming to adaptively modify the injecting current of the energy storage system. The proposed approach is applied to a dc MG testbed that feeds one CPL. Experimental results show that the proposed adaptive controller is able to increase the stability margin and improve the transient response of the dc MG.