Study on Novel Bidirectional AC-DC Converter Circuit of the Wireless Charging for Portable Devices

In this paper, a novel symmetrical topology for the small power high frequency bidirectional AC-DC converter has been proposed, which is applied to the bi-directional wireless power transmission system based on the magnetic coupling resonance. It has dual functions of the inverter and rectifier. The research is mainly reflected in the following aspects: First, based on analyzing the principle of the wireless power bidirectional transmission technology, the operation mechanism of the topology circuit is analyzed emphatically. Second, the feasibility of the designed converter is verified by the simulation of the PSPICE software. Third, the hardware system has been operated at 200 kHz in the modes of the constant current, the constant voltage and the constant resistance, respectively. The results show the maximal output power of the designed circuit is 7.8 W, meeting the design requirement. This circuit has the advantages of the simple circuit structure and simple control. It's suitable for the bidirectional wireless power charging of the small power portable devices.