Huawei Technologies Co., Limited

Newvastek Co., Ltd.

Chengbin Ma

Ming Liu

Ming-Liang Fang

Chih-Hao Chuang

Rui Yang

Xiaosheng Zeng

Xiaokang Liu

Qitang Liu

Shuangke Liu

This application provides a wireless charger and a control method. The wireless charger includes a class-E power amplifier and a tunable impedance circuit that is connected to an output end of the class-E power amplifier. The class-E power amplifier includes a switching transistor and a tunable capacitance circuit that is parallelly connected to the switching transistor. The wireless charger further includes a control unit, configured to obtain a constraint condition of the class-E power amplifier; determine N1 target equivalent load impedances of the class-E power amplifier based on the constraint condition; and adjust a capacitance value of the tunable capacitance circuit in the class-E power amplifier, and adjust an impedance value of the tunable impedance circuit, to enable an equivalent load impedance of the class-E power amplifier to match one of the N1 target equivalent load impedances.

Wireless charger and control method

Example energy balancing circuits and energy balancing apparatus are described. One example energy balancing circuit includes a coupling branch and a receiving branch. The coupling branch includes one sending coil and at least one receiving coil. Each receiving coil is coupled to the sending coil in an electromagnetic induction manner. The receiving branch includes at least one receiving subbranch. Each receiving coil is uniquely connected to one receiving subbranch. Each receiving subbranch includes a rectifier branch. A first receiving subbranch in the at least one receiving subbranch further includes a first boost branch connected to both a first rectifier branch and a first receiving coil. The first receiving coil is a receiving coil connected to the first receiving subbranch.

Energy balancing circuit and energy balancing apparatus

A high-frequency half-wave rectifier system of low-harmonicity and high-efficiency, which mainly comprises: a current output device having an output end and a first flow-return end respectively at both ends, a rectifying module, a resonant tuning unit, a first node, a voltage regulator module, at least one load element, a grounding portion, and at least one flow-return path. By means of the above structure, a simple circuit configuration and appropriate capacitance value setting are used to control the duty cycle of the rectifying module to approximately 74 nanoseconds and adjust the output power and improve the AC to DC conversion efficiency for the rectifying module under the low electromagnetic interference condition.

High-frequency half-wave rectifier system of low-harmonicity and high-efficiency

The AC rectifier system includes an AC source having a positive half-cycle terminal and a negative half-cycle terminal, a first rectifier module along with a first resonance unit having a first terminal connected to the positive half-cycle terminal, a second rectifier module along with a second resonance unit having a first terminal connected to negative half-cycle terminal, a regulator module along with a load element having a first terminal respectively connected to a second terminal of the first rectifier module and a second terminal of the second rectifier module, and a current divider module connected to the positive and negative half-cycle terminals the first terminals of the first and second rectifier modules, and the second terminal of the regulator module. Therefore current would be repeatedly transformed through the current divider module, enhancing heat reduction and transformation efficiency. The resonance units may also function as a filter.

Growing community of inventors

Shanghai, China

Chengbin Ma