Battery wireless charging system for secondary side composite type compensation network

Abstract

The invention relates to a battery wireless charging system for a secondary side composite type compensation network, for providing constant current and constant voltage output required by a battery charging process in sequence. Two kinds of novel composite topological structures, including SS / S-LCL and LCL-LCL / LCL-S are provided; and each novel composite topological structure comprises a high-frequency full-bridge inversion circuit, a primary side compensation network, a loosen coupling transformer, a secondary side compensation network, a constant current-constant voltage switching voltage, and a full-bridge rectifying and filtering circuit separately. Based on the intrinsic characteristic of a circuit, a constant current or a constant voltage irrelevant to a load is realized at specific frequency; conversion of two kinds of modes is realized through the constant current-constant voltage switching network; in addition, approximate zero reactive ring current of the circuit and soft switching of a switching device are realized concurrently, so that the efficiency is improved while the device stress is reduced; and the constant current-constant voltage switching network is placed on the secondary side, so that complex communication between a transmitting end and a receiving end of the wireless charging system is avoided, the control is simplified, and the reliability is improved.

Description

technical field [0001] The invention discloses a battery wireless charging system of a secondary-side composite compensation network, relates to battery wireless charging technology, and is suitable for battery wireless charging occasions such as electric vehicles and medical equipment. Background technique [0002] Wireless charging technology is an emerging technology that uses electromagnetic fields as the medium to transmit electric energy through electromagnetic theory. Since there is no electrical and mechanical connection between the power supply end and the power receiving end, it is easy to use, safe and reliable, so wireless charging technology has great application prospects. [0003] Battery charging usually includes two stages of constant current charging and constant voltage charging, so the wireless charging system needs to provide the battery with the required constant current and constant voltage output. The loosely coupled transformer used in the wireless ...

AI Technical Summary

Problems solved by technology

In order to reduce the number of compensation devices and switching switches, networks with the same compensation parameters and resonant frequency can be optimally combined. Therefore, only the SS / PS and PP / SP composite structures of the four basic compensation networks have the same Resonant frequency and compensation parameters do not require additional resonant devices, and can realize constant current or constant voltage output and reactive power full compensation at the same time, but the mode switch is on the primary power supply side, so the control of the mode switch needs to be controlled through the transmitter and receiver Signal transmission between the communication system, the control is relatively complex, and the reliability is low

In the other two composite structures SS / SP and PP / PS, the mode switch is on the secondary side, which avoids the complicated communication between the transmitter and the receiver, but the compensation frequency and parameters are not exactly the same, so an additional compensation device is required In order to achieve constant current or constant voltage output and reactive power full compensation at the same time

There are also studies that use the same compensation parameters for the two composite structures to achieve constant current or constant voltage switching, but it cannot guarantee that the reactive energy will be fully compensated during the entire working process. The reactive energy increases device stress and reduces transmission efficiency.

[0005] From the above analysis, it can be seen that there is currently no composite structure that can simultaneously realize secondary-side mode switching, approximately zero reactive energy, and constant current-constant voltage output.

Images