Design And Implementation Of Magnetic Coupling Resonance Wireless Power Transfer System Based On Relay Coil

With the development of science and technology and the continuous improvement of people's living standards,a variety of consumer electronic products have emerged and are widely used in people's lives.Electronic products have become an indispensable part of our lives.On the one hand,due to the lack of endurance of some electronic products,the fragmented charging method will become the norm for a period of time in the future.On the other hand,in order to get rid of various wire windings and meet people's pursuit of waterproof performance.The wireless charging standard came into being.It expects the world to have a common set of wireless charging standards.Among them,the Qi standard based on resonant inductively coupled wireless power transfer(WPT)technology is characterized by high efficiency,low price,and easy implementation.The advantages are widely used in consumer electronics products.However,the traditional Qi standard wireless charging system has the shortcomings of short transmission distance and low degree of freedom in charging,which greatly limits the application scenarios and thus cannot realize the true meaning of wireless energy transmission.In view of the shortcomings of traditional Qi standard wireless charging system,such as short transmission distance and low degree of freedom of charging,this paper studies a set of magnetic coupling resonance WPT system based on relay coil.In order to make the system have better compatibility,the system is based on Qi wireless charging standard.Restricted by the size of the receiving end coil,for the problem of low transmission efficiency of large-size transmitting coils and small-sized receiving coil systems at medium transmission distances,this paper proposes a three-coil coupled resonance transmission model,that is,between the transmitting coil and the receiving coil add a relay coil to improve the transmission distance and the degree of freedom of charging while optimizing the system performance indicators.The design of this system is based on the low frequency magnetic coupling resonance WPT technology,with the goal of developing a system with commercial value.The specific research contents are as follows:First of all,this article introduces the research background and significance of the selected topic,the relevant classification of WPT technology and the research status at home and abroad.At the same time,the traditional two-coil coupled resonant transmission model and the three-coil coupled resonant transmission model used in this paper were theoretically modeled and analyzed.By derivation and comparative analysis of the system transmission efficiency,the theory verified the feasibility of the three-coil transmission model.Secondly,through a large number of software simulation experiments,a set of coil design process is summarized,and according to this process,ANSYS Maxwell electromagnetic simulation software is used to match the design of the transmitter coil and the relay coil,and a special coil modeling method is used in the simulation design.Its simulation speed is faster.At the same time,a magnetic shielding structure was designed by analyzing the magnetic field of the transmission model to overcome the problem of high temperature rise caused by the large-scale exposure of the power receiving end to the magnetic field.In addition,the coil wire and magnetic sheet materials were investigated and selected,and the simulation results were tested and verified by winding the physical coil.Thirdly,the main software and hardware modules of the system are analyzed and designed.The hardware part mainly includes inverter circuit power control scheme,resonant network structure,communication demodulation circuit,auxiliary power supply and system protection circuit.Software unpacking architecture design,power control algorithm,object detection algorithm,etc.At the same time,the system control core and some electronic components were also selected.Finally,after analyzing the circuit simulation results of the PSIM system,an experimental prototype of the magnetic coupling resonance WPT system based on the relay coil with GD32E230G8 as the control core was built,and the key waveforms of the system were tested and analyzed to verify the rationality of the system design.At the same time,the performance indicators of the system were tested to evaluate the performance of the system.