The increased number of plug-in electric vehicles (PEVs) on the road is making the PEV charging infrastructure gain an ever-more important role in simultaneously meeting the needs of drivers and those of the local distribution grid. When PEVs are charging, they currently only have the option to charge at a selected current or not charge at all. However, during a power shortage, the charging infrastructure should have the option to either shut off the power to the charging stations or lower the power to the PEVs in order to satisfy the needs of the grid. The current approach to charging is not well suited to scaling with the PEV market. If PEV adoption is to continue, the charging infrastructure must provide a seamless and configurable interface from the vehicle to the power grid and overcome its current shortcomings, such as underutilization of circuits, unresponsiveness to grid constraints, low degree of autonomy, and high cost. In particular, there is need for technology that controls the current being disbursed to these PEVs.
The WINSmartEVTM smart charging infrastructure is proposed and is currently being developed to meet the growing demand for charging from an ever increasing population of PEV owners. It has five major components: smart charging stations, a server-based control system, systematic safety integration, an authentication and authorization system, and smart charging algorithms. This software-based technology is capable of providing power to several PEVs using scare charging resources by multiplexing or current sharing. Collaboration between the server-based central controller and the local controllers inside the charging stations facilitates the management of the charging sessions and control of the current to the PEVs. This technology provides PEV chargers that simultaneously connect to multiple PEVs and a system that takes into account external factors, such as grid capacity when scheduling smart charging sessions. It not only incorporates intelligence at every level so that charge scheduling can avoid grid bottlenecks, it also multiplies the number of PEVs that can be plugged into a single circuit.