Large scale integration of EVs into the grid and its potential effects on power system reliability

A distributed smart charging algorithm is introduced in this paper to coordinate the stochastic charging behaviors of large amounts of electric vehicles (EVs). Each EV has some level of intelligence and communication abilities to make charging decisions to achieve its own maximum benefits. Meanwhile, the EV aggregators use the smart pricing and sequential price update mechanisms to influence the charging behaviors of EVs. A binary hybrid GSA-PSO algorithm is used to solve each EV's charging optimization problem. The potential effects of large scale integration of EVs on power system reliability is also discussed. Numerical case studies show this distributed smart charging algorithm is able to effectively transfer the EV charging load from the peak hours to the valley hours, and therefore greatly reduce the system peak load. Additionally, it is beneficial to improving the power system's reliability level.