Optimal load ratio control for dual-receiver dynamic wireless power transfer maintaining stable output voltage

Dynamic wireless power transfer (DWPT) system can provide a power supply for electric vehicles (EVs) in motion which can increase the available charging time, lessen the anxiety of driving range, and reduce the batteries in EVs. Aimed at optimising the system efficiency while regulating the output voltage, an optimal load ratio control strategy is proposed to optimise the power distribution of the dual-receiver DWPT system, and to reduce the losses of the system as the receivers move along the transmitter track. The control strategy is implemented in the receiver side without the mutual inductance detection and the communication with the transmitter side. With the proposed method, the efficiency of the DWPT system can be optimised while the output voltage of the system can be regulated simultaneously. An experimental prototype is set up to validate the proposed method. The system efficiency with proposed method reaches 90.8-91.9% during various conditions in the experiments. The maximum efficiency improvement is 2.5% compared with the efficiency of the single receiver method, and it increases to 2.6% compared to that of the current balancing method.