Design and Development of an Optimal Distributed Generation and Hybrid Storage System for Microgrids

Today, nations all around the globe are progressing towards cleaner environment, which have made the concept of distributed power generation from renewable energy (RE) resources more desirable. Due to the increase in the development of new power generators, such as wind and solar PV, integrating renewable and non-renewable sources in the main electricity grid becomes a challenging subject as they can harm the quality and reliability of the grid due to their uncertain generated power. This situation brings about the concept of distributed generation (DG) microgrids and calls for innovative contribution from researchers in this fast-emerging field. This proposal presents an optimum model for such DG system along with a hybrid energy storage system to supply a given demand. The proposed project is widely applicable for power system operators and utilities around the Kingdom, that are developing strategies to handle multiple DG resources, which can prove to be very useful in building a national capacity of renewable energy based DG projects in urban areas as well as remote localities. This project utilizes the emerging concept of hybrid energy storage system (HESS), coupling battery energy storage with supercapacitor technology. These two technologies constitute a powerful combination since battery has high energy density and supercapacitor has high power density and cycle life. These complementary features can be beneficially mingled to enhance the performance and lifespan of the storage system with low weight and cost. A practical model for the HESS is proposed that can account for various constraints on charging/discharging rates, power and energy capacities. While the proposed DG microgrid model maintains the supply-demand balance continuously, its main objective is to minimize the operational costs. This goal is achieved via developing modern computationally efficient algorithms for optimal energy management, keeping in view the realistic system limitations and practical considerations. An optimal control based approach with predictive structure such as model predictive control, dynamic programming etc. is best suited in this situation. These control schemes are preferred due to their ease of implementation, systematic handling of constraints and future prediction of system behaviour using power and price forecasts. The successful completion of this project will not only offer a mechanism for power system operators to reliably design and operate a DG system with large scale RE penetration but will also help them in the decision-making process of generation scheduling while satisfying the technological and economic constraints. Furthermore, the proposed HESS is also expected to enhance the energy storage system performance with reduced costs. Hence the proposed project can become a valuable step to meet the objectives of the Saudi Arabia Vision 2030 for renewable energy integration into the electricity grid and can also bring remarkable benefits for modern life requirements and environmental health preservation of the society at large.