Low-electric-field emission end coil for wireless charging

Abstract

The invention discloses a low-electric-field emission end coil for wireless charging. The low-electric-field emission end coil for wireless charging introduces tuning capacitors between single coil bodies of a common emission end coil, wherein the tuning capacitors are used for reducing adverse effects of parasitic capacitance of the tuning capacitors and reducing radiation interference of EMI and RF interference (RFI); the capacitance of the tuning capacitors makes the single coil bodies generate self resonance, avoids accumulation of alternating-current voltage between turn numbers of adjacent coils and makes a simultaneous minimum electric field of the near-field magnetic field effect generated. The low-electric-field coil is provided for resonant wireless charging product series, and has the advantages of being smaller in electric field interference, and capable of passing the FCC EMI certification more easily and providing a stable coil for large-area 1:N charging application.

Description

technical field [0001] The invention belongs to the technical field of wireless charging, and in particular relates to a low electric field transmitting coil for wireless charging. Background technique [0002] The A4WP-based wireless charging system works at 6.78MHz, and the coil design of its power transmitting end (PTU) usually requires a multi-turn spiral structure to meet the requirements of magnetic field consistency and coupling with the power receiving unit (PRU). The biggest challenge lies in the design of the coil, especially a coil with a large area. Since the accumulated parasitic capacitance will be larger compared to coils operating at low frequency or small size, the energy loss will also be greater. [0003] In the simple circuit model and equivalent parasitic capacitance of the wireless charging coil in the prior art, the equivalent parasitic capacitance C represents the sum of the parasitic capacitance between single turns of the coil, L represents the tot...

AI Technical Summary

Problems solved by technology

[0011] The purpose of the present invention is to provide a low electric field transmitter coil for wireless charging, which aims to solve the problem that the traditional wireless charging coil design is limited by its own parasitic capacitance, so that the location flexibility and electrical transmission power will be limited, thus Issues Affecting Power Transmission Distance

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