Charging Area Determining and Power Enhancement Method for Multiexcitation Unit Configuration of Wirelessly Dynamic Charging EV System

Electric vehicle (EV) dynamical wireless charging is an emerging application area of wireless power transfer technologies. Compared with a classical static charging mode, there are two key challenges in a dynamical charging process. One is to determine charging area and corresponding excitation unit. The other is to provide large energy in a short time interval. Based on multiexcitation unit configuration for EV dynamical charging, this paper proposes a charging area determining method. The dynamical mutual inductance can be calculated based on dc current input and load detection. A charging area can be figured out based on output power requirement. And a switching mode method is given to control the charging process for multiexcitation unit configuration. On this basis, a power and efficiency enhancement method is proposed by utilizing a multiexcitation unit in the charging area. This method is beneficial for improving system power capacity without increasing the voltage and current stress. Finally, experimental results show that this method can realize accurate charging area determining and control. And the output power of dual excitation unit configuration can increase almost four times than that of a traditional single excitation unit configuration.