Effect of autonomous distributed vehicle-to-grid (V2G) on power system frequency control

Penetrating large amount of renewable energy sources into power system, battery energy storage performs an important role for smoothing their natural intermittency, ensuring grid-wide frequency stability, and suppressing voltage rise caused by reverse power flow. The ubiquitous power grid is one of the concepts as a smart grid in Japanese context, where the total battery capacity can be optimized by coordinating renewable energy sources, controllable distributed generators, and controllable loads on demand side, for example, heat pump based water heater with heat storage, and plug-in hybrid vehicle or electric vehicle with onboard battery, and so on. These controllable devices behave as an autonomous distributed smart storage by charging or discharging against the power system frequency measurement as paying attention to user convenience. In this paper, effects of the autonomous distributed smart storage on bulk power systems are investigated thorough a load frequency control simulation.