An Evaluation of UWB for Location-Based Hands-Free Authentication Charging of Electric Vehicles

Charging Stations (CSs) serve as a point of contact between electric vehicles (EVs) and the electrical distribution network. The management of CSs and their functions is becoming increasingly important for the Distribution System Operators (DSOs). The Open Charge Point Protocol (OCPP) provides DSOs with a key tool for managing CSs. The OCPP standard specifies various authorization methods, ranging from the most traditional, such as card Near Field Communication (NFC), to the use of ISO 15118 External Identification Means (EIM). This work investigates the use of a hands-free charging authorization system based on the location of the customer, who intends to charge the EV, in relation to the charging infrastructure. This paper evaluates the possibility of using Ultra Wide Band (UWB) technology to localize and identify customers in proximity of a CS. The authors proposed a dual radio prototype, that exploiting low-power BLE signal as proximity detector, can identify the position of a potential customer with an accuracy of about 0.25 m (even at a distance of 3 meters), while ensuring 5 times longer battery life with the respect to single UWB radio solution.