An Optimal Energy Management Strategy for Standalone DC Microgrids

Abstract

The energy management strategies are becoming vital for proper power sharing and voltage regulation purposes now a days.The usual energy management methods mainly depends up on MPPT techniques and sometimes based on batteries in case of excess or deficit of energy.For the constant voltage and current charging of batteries and also to increase their life span, a flexible energy management method is to be introduced.So here, a synchronized energy management strategy is offered with the help of "Nonlinear Model Predictive Control Algorithms (NMPC)". This method makes the wind turbine and a photovoltaic array of a standalone DC microgrid as controllable power generators by adjusting the switching duty cycles of converters and the pitch angle of wind turbine .The technique is developed as an online NMPC based algorithms.By applying this proposed method to a standalone dc microgrid,the controller can realize the constant current and voltage charging of battery cells.The changing load demands can be accurately shared between corresponding generators.Also the voltage of DC bus can be easily regulated with in a specific range.