Assessment of impact of distributed generators, plug-in electric vehicle and Battery Energy Storage System on power distribution losses

Distributed generators (DG) and renewable energy sources have been attracting special attention to distribution systems. Renewable energies, such as photovoltaic (PV) and wind turbine generators, are used as green energy. However, the large amount of DGs causes voltage deviation beyond the statutory range in distribution systems. Also, since Electric Vehicle (EV) is getting more and more popular, it can be used for demand response applications. Consequently, control of distribution systems can be more flexible. Due to the intermittent nature of DGs, Battery Energy Storage Systems (BESSs) are assumed to be introduced and share to the same inverter with PV generator in houses and buildings. Moreover, to the power flow at interconnection point, i.e. distribution substation, fluctuates substantially. Therefore, a large capacity BESS is introdused at that point. For an optimal distribution system operation, this paper poposes a decision technique of an optimal reference scheduling of the BESS introduced at distribution substations, inverters interfaced with DGs and their BESSs, EVs, and the existing voltage control devices. The aforementioned control objectives are formulated as an optimization problem and solved by Particle Swarm Oprimization (PSO) algorithem. The effectiveness of the proposed method is verified by numerical simulations using MATLAB®.