Identification and positioning system for inductive charging systems

Future inductive charging systems for dynamic charging (e.g. on streets) as well as for static charging (e.g. for parking lots) depends on very exact and accurate vehicle position and pickup position, respectively. This paper focuses on a positioning and identification solution using a wireless system for electric vehicles to realize the controlling and management for inductive charging. This solution is based on Radio Frequency Identification (RFID) systems which are used for the positioning as well as for identification of electric vehicles. For static systems the signals and position data of the received RFID transponders will be used for the position calculation. If necessary also the signal quality will be normalized to analyze all received transponder signals and to enhance the positioning accuracy. For dynamic systems the position data of the RFID transponders are not required. The use of a RFID system for the identification of the vehicle has also the advantage to support the charging management system with identity information about the target vehicle. In addition the paper also includes a description of an end to end solution with different communication entities comprising the charging and controlling system. This includes the power inverter for the primary inductive charging coils as well as the data transfer between vehicle and management to get vehicle specific information like battery status and vehicle speed. The solution must support a fast data transfer to provide necessary vehicle identification and information about its positioning in time. Also the power inverter needs real-time data transfer. Especially the activation and deactivation process of the primary coils is a time critical factor. These coils should only be activated if a vehicle pickup or chassis covers the primary coil and the vehicle is able to charge. Finally, the paper describes a higher layer management and controlling system which is needed for the inductive charging by drive as well as on parking lots. This system has to gather the data from the involved entities (e.g. vehicles, RFID systems etc.), process the information, and to calculate the time stamps for activation and deactivation of the inductive charging coils.