Control of Mixed Energy Storage System Based Micro-grid Using Modulator-Less Model Predictive Control

A grid interactive microgrid with mixed storage system is gaining appreciable attention in commercial and residential applications. Effective control is one of the key concerns in deployment of microgrids. Compared to conventional control strategies, dynamic model prediction based control schemes has better dynamic performance and can handle the inherent non-linearity of power electronic converters. Faster dynamic response as a basic requisite, this paper presents a modulator-less model predictive control (MPC) scheme for grid interactive microgird, which comprises Photovoltaic (PV) and Battery-Super capacitor (SC) based Mixed Energy Storage (MES). The complete control scheme consists of (i) A proportional-integral (PI) controller which generates the reference current to regulate dc-link voltage, (ii) A low pass filter (to segregate average and oscillatory components) with power managing scheme and (iii) Finite Control Set Model Predictive Controller (FCS-MPC) which controls the power converters to track the reference currents. The effectiveness of proposed scheme is verified through simulation results.