Microgrids Availability Evaluation using a Markov Chain Energy Storage Model: a Comparison Study in System Architectures

This paper investigates the effect of energy storage systems on the availability of microgrids with different architectures in the presence of renewable energy sources (RESs). When RESs are used for power generation within a microgrid, its availability may be reduced due to the intermittent nature of RESs. Thus, energy storage systems may be used as a solution to improve microgrids availability. Therefore, it is important to have a realistic evaluation of microgrids availability and to determine how added energy storage affects microgrids. Since energy storage system is not just a one-time-use reserve, charging and discharging processes in energy storage need to be considered when their availability is evaluated. Thus, a Markov chain model is used in this paper to properly represent the charging and discharging processes of energy storage systems, and minimal cut sets method is used in order to evaluate the availability of different microgrid architectures. Using the proposed method, availabilities of radial, ring, and ladder type microgrid architectures are evaluated in the presence of RESs and energy storage systems, and results are discussed.