An autonomous distributed vehicle-to-grid control of grid-connected electric vehicle

Penetrating large amount of renewable energy resources into power system, battery energy storage system perform important role for smoothing their natural variability, ensuring grid-wide frequency stability, and suppressing voltage rise caused by reverse power flow. The ubiquitous power grid concept has been proposed as a Japanese smart grid, in where total battery capacity could be optimized by coordinating controllable distributed generators, loads on demand side, for example, heat pump system with heat storage, and plug-in hybrid vehicle or battery electric vehicle with onboard battery. In this paper, we propose a vehicle-to-grid control of grid-connected plug-in hybrid electric vehicle and electric vehicle as a kind of the demand response in the ubiquitous power grid. Proposed control is based on simple droop characteristics against the power system frequency at plug-in terminal, and considers the risks about use for vehicle and battery condition. Autonomous distributed Smart Storage for governor free control, spinning reserve, local area voltage control, and other smart grid applications is realized by packaging the proposed control to automotive power electronics circuit and electric control unit.