City University of Hong Kong

Convenientpower Hk Limited

Wing Choi Ho

Shu Yuen Ron Hui

Xun Liu

Chi Kwan Lee

Wai Pong Choi

Shu Hung Chung

Wing Cheong Chan

Ron Shu Yuen Hui

This invention provides an electronic control method for a planar inductive battery charging apparatus on which one or more electronic loads such as mobile phones, MP3 players etc can be placed and charged simultaneously. The power control circuit of the charging pad consists of two power conversion stages. Depending on the nature of the input power supply, the first power stage is an AC-DC power converter with variable output voltage control and a second stage is a DC-AC power inverter with constant current control. The combination of the two stages provides power control of the charging pad and generates AC magnetic flux of ideally constant magnitude over the charging areas within a group of primary windings that are excited.

Electronic control method for a planar inductive battery charging apparatus

A full-bridge rectifier is configured to provide synchronous rectification with either a current-source or a voltage-source. The rectifier has an upper branch and a lower branch and two current loops, with each of the branches including voltage- or current-controlled active switches, diodes or combinations thereof that are selected such that each loop includes one active switch or diode from the upper branch and one active switch or diode from the lower branch, and each current loop comprises at least one diode or current-controlled active switch, and at least one voltage- or current-controlled active switch is included in one of the upper or lower branches.

Single-phase self-driven full-bridge synchronous rectification

Various circuit configurations and topologies are provided for single and multi-phase, single-level or multi-level, full and half-bridge rectifiers in which diodes are replaced by combinations of voltage-controlled self-driven active switches, current-controlled self-driven active switches and inductors in order to reduce the effects of conduction loss in the diodes.

Generalized AC-DC synchronous rectification techniques for single- and multi-phase systems

The present invention provides an AC-DC converter and AC-DC conversion method for converting an AC input provided by a power transfer winding. The AC-DC converter includes a rectifying means for rectifying the AC input into a rectified output, and a control means for controlling the rectifying means based on a comparison between a reference signal and a voltage feedback signal, the voltage feedback signal being based on the rectified output.

AC-DC converter and AC-DC conversion method

Methods and principles are described for systematizing localized charging, load identification and bi-directional communication in a planar battery charging system. Also described is control circuitry for selectively energizing a primary winding when a load is placed on the platform. The optimization of the size of the receiver winding compared to the transmitter winding is discussed, while the associated communication methods include techniques for load identification, compatibility checks, hand-shaking and communication of charging status.

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Hong Kong, China

Wing Choi Ho