| Magnetic resonance radio energy transmission is an important research direction in the field of wireless charging.It can realize efficient energy transmission under medium transmission distance.The output power of the system can be up to several kilowatts,and the two coupled coils have the degree of alignment of Higher tolerance.Using the principle and application characteristics of magnetic resonance radio energy transmission,an output power of about 500 W,a transmission efficiency of up to 84%,a secondary resonant circuit of only 250 g and a horizontal offset distance can be developed for electronic equipment such as drones.A 30 cm wireless power transmission system prototype.The basic components of the wireless energy transmission system are described.The electrical parameters of the basic resonant unit are studied,the voltage-current relationship on the energy storage device is analyzed,and the conversion process of electrical energy and magnetic energy is derived.Then the two-port equivalent network analysis method is used to analyze the output characteristics of the system as a whole.A model based on mutual inductance coupling theory is established.The parameters of four common resonant compensation networks are deduced,and the expressions of parameters such as output power are calculated,which lays a theoretical foundation for the determination of system parameters.Using the finite element ANSYS simulation software,the planar spiral circular structure coil is modeled and simulated,and the cloud image of the magnetic energy transmission system is obtained.According to the parameters of self-inductance and mutual inductance derived from single-turn coil modeling analysis,the analytical solution between system transmission distance,coil radius and transmission efficiency is calculated.The advantages and disadvantages of using hollow copper tube,multi-strand Litz wire and PCB on-board wire wound coil are analyzed,and the value of compensation capacitor is determined.Use Math CAD to plot the relationship between coil parameters and output power.The energy transmission system is mainly composed of surge protection circuit,full bridge inverter circuit,EMI circuit,PFC circuit and other circuits.It analyzes the circuits of each stage and provides the selection and design methods of the main components,such as the winding of the inductor..Simply expounding the characteristics of common inverter circuits,combined with system design requirements,finally selects the full-bridge inverter circuit.In order to reduce the switching loss of the functional circuit,soft-switching technology is introduced.Then use MATLAB to model and analyze the system.The oscilloscope output related waveform is completely consistent with the theoretical analysis in Chapter 4.Finally,the output characteristics and anti-offset capability of the system were tested.The experimental results show that the prototype can transmit efficiently and has strong anti-offset capability. |
PDF Full Text Request