High-efficiency resonant wireless electric energy transmission system

Abstract

The invention provides a high-efficiency resonant wireless electric energy transmission system. The system comprises (1) a serial resonance network composed of coupling coils LTx and LRx and resonantcapacitors CTx and CRx; (2) an E type inversion circuit composed of an emitting-side input voltage Vdc, an input choking inductance Lin, a main switch tube MTx and a parallel capacitor Cds1 thereof; and (3) an E type synchronous rectification circuit composed of a receiving-side output capacitance Co, an output choking inductance Lout, a synchronizing switch tube MRx and a parallel capacitor Cds2thereof The E type synchronous rectification circuit replaces a routine diode for rectification, the conduction loss of the diode can be reduced greatly, and the system efficiency is improved; a synchronous rectification control signal is independent from an emitting-end signal, ON and OFF information is obtained directly from a conducting voltage drop position of the synchronizing switch tube MRx, and problems of the traditional synchronous rectification technologies are overcome; and the problem that a traditional linear auxiliary source is low in efficiency can be solved by means of a high-efficiency auxiliary source circuit which takes energy on the basis of a transformer, and the total efficiency of the system is improved.

Description

technical field [0001] The invention relates to a power transmission system, in particular to a high-efficiency resonant wireless power transmission system. Background technique [0002] The core architecture of the magnetic coupling resonant wireless energy transfer system is as follows: figure 1 As shown, through two inductance coils L Tx and L Rx The coupling realizes the transmission of electric energy. Due to the existence of coil leakage inductance, the transmitted power and efficiency are very low in the direct coupling state. Therefore, the inductance coil and the capacitor are connected in series to form a resonance to form a resonant wireless energy transmission system to improve efficiency and power. figure 1 in, U in is the input AC source, L Tx and L Rx is the coupled inductance coil, C Tx and C Rx is the resonant capacitor, R Tx and R Rx is the internal resistance of the resonant tank, R L is the equivalent AC load resistance. However, the core arch...

AI Technical Summary

Problems solved by technology

However, the Class D resonant power amplifier circuit has some inevitable defects: (1) The bridge circuit requires a dead zone circuit, so the maximum operating frequency is limited; (2) The bridge circuit drive will have a latch-up effect, which affects system reliability; (3) The discontinuous input current requires an additional input filter circuit; (4) The longer diode reverse conduction time reduces the system efficiency

[0007] However, there are still many problems to be solved in the "DC-DC" wireless energy transmission system under the E-class topology, including: (1) the loss of the diode on the rectification side is large, which affects the system efficiency; (2) the traditional synchronous rectification technology needs The terminal transmits the signal to the receiving end, but it is different from the general isolated power supply in the wireless charging application. Due to the distance limitation, it is impossible to add an additional transformer or optocoupler to transmit the synchronous rectification information; (3) in the application of higher voltage (>24V) In this case, if the auxiliary power supply of the transmitting end and the receiving end is powered by a linear circuit, additional power consumption will be generated and the system efficiency will be reduced.

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