Analysis of Load Following Strategies for Grid Connected Microgrid having Renewables and Energy Storage

Abstract

Microgrids offer a decentralized source for electrical loads that be able to run either in island approach or simultaneously with the main power grid. A grid-connected microgrid that includes solar panels, four wind turbines, battery storage, and an AC/DC converter has been proposed. Load following method is used as the optimal load-dispatch option to lower both the net present cost and levelized cost of energy of the proposed microgrid. The overall peak load is decreased when a certain electric load is separated as deferrable. This microgrid is connected to the grid, so in a crisis, the system can draw electricity from the grid. It is also feasible to transfer extra electricity to the grid when the microgrid contains more electricity than it needs. The development and refinement of a grid-connected microgrid network using an effective load-dispatch method is explored in this thesis. The performance of the system is evaluated by defining the perfect size of individual elements, doing various cost studies on it, and tracking its responses. The microgrid generates 43,119 kWh of solar energy per year and 137,494 kWh of wind energy per year. In general, 14,440 kWh per year and 127,876 kWh per year of energy is purchased and sold from the grid, respectively. Load following strategies restrict the battery to charge when there is an unmet load in the microgrid. Energy storage device charging is possible only by using renewable energy resources. Besides, deferrable load decreases the system impact of the load during peak hours. The proposed microgrid has the lowest levelized cost of energy of 0.151 dollars than any other combination found during simulation. The thesis result provides a guideline for estimating the components’ sizes and probable costings for their optimal operations for any microgrid. Although this study was conducted with specific site data from Bangladesh, the findings apply to any location on the planet with similar geographical conditions and load profiles