The Feasibility of Self-Resonant Structures in Wireless Power Transfer Applications

The efficiency and range of wireless power transfer (WPT) is dependent on the Q of the resonant coils. The multi-layer self-resonant structure (MSRS) has been shown to have Q more than 6x conventional coils. This structure has an integrated capacitance, which limits the minimum achievable size and frequency. In this paper, we explore the minimum feasible resonant frequency and the maximum power level without dielectric breakdown that can be achieved using the MSRS given a size constraint. This analysis is applied to two case studies; one for consumer electronics and one for electric vehicles. The example MSRS for electric vehicles has a diameter of 20 cm and height of 5 cm. If a 100 kHz resonant frequency is selected, the MSRS can achieve an output power of 10 kW at a range of 20 cm with an input voltage of 500 V.