Directional Analysis Of Wireless Power Transfer And Design Of Omnidirectional Three-dimensional Coupling Mechanism

Wireless power transfer(WPT)technology frees the electrical equipment from the restraint of the electric wire.Its flexible,efficient and convenient characteristics make it a powerful complement to the traditional electrical transmission,and has received extensive attention in many application fields.Among them,the wireless power transfer via coupled magnetic resonance(CMR)technology can realize high-efficiency power transmission at a long distance and has strong anti-misalignment ability,so it provides technical support for wireless charging of electrical equipment such as wireless sensor networks,drones,portable electronic devices,mobile robots and,etc.Traditional wireless charging platform cannot overcome the deviation of angle and position." flitch plate type " wireless charging can no longer meet the wireless charging requirements for small electrical equipment,which also affects the further promotion of wireless power transmission technology.The current research on CMR-WPT has evolved from a directional single-dimensional system to a full three-dimensional system.However,the CMR-WPT system itself has a certain degree of nondirectionality.The directional analysis of the energy transmission system is helpful to the design and optimization of the three-dimensional system.This paper deeply studies the directivity of the CMR-WPT system and designs a three-dimensional wireless power transmission system based on the conclusions of relevant regularities.This provides an important reference for the optimal design of the coil,but also provides a feasible method for three-dimensional wireless charging.Firstly,according to the theoretical analysis of the direction of the CMR-WPT system,the influence of mutual inductance on the energy transfer efficiency of the system is obtained.Analyze the influence of the angle offset on the mutual inductance from the perspective of the mathematical model,and then obtain the directivity law through theoretical analysis.At the same time,the characteristics of the omnidirectional three-dimensional wireless power transmission system are analyzed by combining the equivalent circuit model and mutual inductance superposition theory.Secondly,finite element simulation is used to quantitatively analyze the directionality of the energy transmission system from the dimensions,distance,shape,etc.of the coupling mechanism on the basis of theoretical analysis,and obtain the optimal non-directional range system parameters.Establish an array-type threedimensional power transmission system simulation model,analyze the magnetic field distribution of different control methods,and analyze the system transmission performance.Finally,an experimental system is built based on theoretical analysis and simulation models to verify the directionality of the CMR-WPT system.It is proved that the energy transmission of different distances,different coupling coil radius ratios and different coil types of the energy transmission system has no directional law.At the same time,a three-dimensional power transmission experimental system was built to verify the transmission characteristics of the magnetic field strength at different positions in the space obtained in the simulation.The experimental results show that the transmission efficiency of the CMR-WPT system can remain stable within a certain range of the angular offset of the receiving coil,and the range of the offset is related to the system parameters.At the same time,the three-dimensional wireless power transmission system has good transmission performance in space.