A dual-excitation inductive power transfer system with decoupled transformer for high misalignment tolerance

Abstract

This study delves into the design and optimization of a 4 kW dual-excitation inductive power transfer system designed to accommodate large misalignments. The system utilizes a bipolar-solenoid inductive coupled transformer as its coupling mechanism. Detailed simulation and analysis of this coupling mechanism are conducted. Additionally, the system employs a control strategy aimed at optimizing the coordination between output power and efficiency. This control strategy dynamically adjusts the power of the two transmitters, aiming to enhance system efficiency to the maximum extent possible under favourable coupling conditions. Moreover, it ensures that the system's output power remains at or above the rated value even when coupling conditions deteriorate. During the experiment, the system can optimize the output power and efficiency at the same time by using a suitable control strategy when the coils are misaligned. Meanwhile, the system can achieve a minimum efficiency of 81.5% even when the misalignment distance reaches 300 mm (60% of per transmitting coil size). The system and control strategy proposed in this paper can effectively overcome the deterioration of the output characteristics of the wireless power transfer system when misalignment occurs.