Research On Key Problems Of Qi Standard Mobile Phone Wireless Charging System

With the progress of science and technology,wireless charging technology is becoming more and more mature,and more and more people are beginning to realize the impact of wireless charging technology on the world's technology wave.The application of wireless charging technology can not only reduce security risks and provide convenience for people's life,but also reduce the use of consumables,in line with the theme of social development,energy conservation and environmental protection.In the early stage of the development of wireless charging technology,due to the inconsistency of standards and the limitation of the development of technology,it was difficult for wireless charging products to be widely used,so the products entering the market did not have much influence.Slowly,the industry rolled out the first international standard for wireless charging,QI,which guarantees the compatibility of wireless charging products and is recognized by most technology attacks.Then,the world's corporate giants,research scholars once again set off a wave of research on wireless technology,wireless charging technology is once again favored by the world,all kinds of consumer electronic products have also emerged.In this paper,Qi protocol standard is used to study many key problems,and an electromagnetic induction coupling radio energy transmission system is designed.This paper starts from the theoretical aspect and studies the problems related to the system design,which provides a reliable theoretical basis for the subsequent circuit design.Then the results of calculation and simulation are verified with the measured data to ensure the correctness and feasibility of the scheme design.The detailed work arrangement of this paper is as follows:Firstly,it introduces the significance of the research on this technology,analyzes three kinds of radio energy transmission modes at present,and analyzes the research status of this technology at home and abroad.Then the whole system is modeled and theoretically analyzed,including the power and efficiency of the system,and the research of compensation network.And efficiency as the key words first equivalent circuit of induction coupling power transmission system is analyzed,and the coil design make detailed theoretical research,the simulation results show that under the condition of higher power,coil loss is about 500 mW,the coil coupling transmission efficiency is as high as 95%,5W and 15 W the measured efficiency is as high as 94%,the results also showed that coil winding loss minimum.On the basis of existing theories,peripheral circuits are designed around the Qi protocol,and FOD function design is the focus of this paper.Through the design of this paper,foreign bodies can be detected quickly and accurately within 300 microseconds,and the detection speed and accuracy are not affected by temperature.Finally,the simulation test analysis and optimization of the whole system and each module make the total transmission efficiency of the whole system from the distribution end to the load receiving end reach more than 80% in the case of low-power energy transmission,and about 70% in the case of high-power transmission above 15 W.The radio energy transmission system designed in this paper also has some shortcomings.At the end of the paper,the author makes some summaries and prospects for the future research direction and goals.