Resonant Network Transformation and Implementation of a Compacted Four-Plate Capacitive Power Transfer

The application of capacitive power transfer (CPT) technology is widely researched to overcome the drawback of inductive power transfer (IPT) technology. The main drawback of IPT is not only eddy-current losses generated by magnetic fields in the foreign object located in the air-gap but also the pad size and total cost considerations. This paper implements a four-plate compact capacitive coupler for suficient air-gap distance CPT as proposed by other scientific paper. The four-plate arrangement is also designed by referring to the previous research which results in a good coupling capacitance. The LCL compensation is utilized to resonate with the four plates coupler. The resonant network equation is proposed in previous research by employing the superposition theorem to analyze the two AC sources in the coupler separately. Whereas, this paper proposes the resonant analysis by implementing wye-delta and delta-wye transform in the equivalent impedance network. Hence, that approach could bring a contribution by generating a gain curve for further study. The circuit model is simulated in PSIM software to verify the gain curve and specific resonant parameter. The ANSYS Maxwell software is employed to simulate the coupler design. Finally, a 260-W prototype of the CPT system with a 60-mm air-gap distance is constructed and experimentally tested to validate the gain curve and mathematical analysis for the equivalent impedance network, as the main focus of this research.