Simultaneous wireless power and data transfer for electric vehicle charging: a review

Abstract

Wireless charging of Electric Vehicles (EVs) has become an important research topic in recent years. During the wireless charging process, wireless data exchange must take place between the EV and the charging station. Battery status, current and voltage of the charger or the EV identification may be required on the primary side in order for the system to operate properly. This data exchange can be carried out through commercial wireless communication solutions such as Bluetooth, 802.11 or ZigBee. However, these technologies introduce cybersecurity problems, high and variable transmission delays and possible connection losses during communication. To address these issues, numerous solutions have been proposed based on wireless data transmission through the wireless power transfer circuit. This paper gives a comprehensive review of the different issues that need to be considered for simultaneous wireless power and data transmission (SWPDT) for wireless EV charging applications. This context represents a challenge for SWPDT due to the power levels and the high probability of operating with notable misalignments or even with the EV on move. Specifically, a classification of SWPDT systems is described, and six different criteria to consider when designing a SWPDT system are analysed for EVs. The suitability of different system configurations is evaluated according to three representative use cases: (i) providing maximum efficiency, (ii) synchronisation for bidirectional wireless chargers and (iii) dynamic charging. We have also analysed the feasibility of using the Open Charge Point Protocol (OCPP) together with ISO 15118, which is the most popular communication protocol used in EV charging infrastructures.