Research On Wireless Charging System Of Mobile Phone Based On Array Coil Magnetic Resonance Coupling

In recent years,wireless energy transmission technology has developed rapidly and it is widely used in wireless communication systems.Magnetic resonance wireless energy transmission has the advantages of safety,large transmission distance and large transmission range.It has become the focus of research at home and abroad.At present,magnetic resonance wireless energy transmission technology has problems such as low transmission efficiency,unbalanced magnetic field distribution,sensitivity to distance,and less research on its practicability.In this regard,this paper designs a high-efficiency coil array structure with balanced magnetic field distribution for wireless charging of mobile phones,and further promotes the development of magnetic resonant wireless energy transmission technology.The specific research contents are as follows:This paper presents a heterotopic partially overlapping 2 × 2 emission array.The transmitting resonant coil is printed on different layers,and the two parts are arranged to overlap each other.A resonant capacitor is used to adjust the frequency of the four resonant coils in the array.The entire array of coils is easier to make.The measured efficiency of the array is 73%,which is higher than 60% of the conventional planar 2 × 2 array.In addition,the difference between the highest efficiency and the lowest efficiency in the 3 cm plane above the array is 4%,which is less than 18% of the conventional planar 2 × 2 array.Therefore,this array has a more uniform magnetic field distribution.This paper proposes to alleviate the problem of rapid decline in transmission efficiency due to changes in transmission distance by adjusting the capacitance of the receiving coil.By adjusting the receiving coil capacitance scheme,the transmission efficiency can be increased by more than 10% when the transmitting and receiving coil is 8 cm away.This paper designs an E-class amplifier as a supplier of energy in the transmit array coil.The measured results show that the output power of the power amplifier is 10.11 W,which meets the power demand of mobile phones.Finally,this paper sets up a rectifier regulator board.And built a wireless charging system for wireless charging of mobile phones.The measured results show that the charging current of the mobile phone is maintained at 940-960 mA in the area above the overlapping array.The overall transmission efficiency is maintained above 45%,with high transmission efficiency.