| When solving the charging needs of mobile electrical equipment in special scenarios such as mines,underwater,and nuclear environments,wireless power transmission technology has the advantages of convenience,safety,and reliability.However,the transmission performance of wireless power transmission systems is affected by factors such as transmission distance,operating frequency,and load.When the system parameters change,the output power and efficiency may decrease rapidly.When dealing with moving electrical equipment,the relative position of the electrical equipment and the power supply terminal is constantly changing,resulting in changes in the equivalent parameters of the system,which may lead to a rapid decrease in output power and transmission efficiency.Therefore,thesis proposes a mobile magnetic resonance wireless power transmission system for the wireless charging requirements of mobile devices.Firstly,the circuit mutual inductance model of the resonant system is constructed,and the influence of operating frequency,mutual inductance and load on the output power and efficiency of the system is analyzed,which provides theoretical support for subsequent hardware circuit design and optimization.In the hardware system design,the circuit topology of class E power amplifier is studied in this paper,the influence of bypass capacitor,choke inductance and equivalent load on the system efficiency is analyzed,and the parameter optimization design of the power amplifier is carried out.Then,according to the mathematical model of the coil,the influence of the radius,turns and wire diameter of the resonant coil on the output power and efficiency of the system is analyzed,and the parameters of the coil are optimized.Then,the problem that the system is detuned due to the change of the relative position of the coil during the charging process of the moving load is studied,and the transmission performance of the system is deteriorated,and a frequency tracking control strategy based on the emission current is proposed to solve this problem.In thesis,a mobile wireless power transmission experimental platform is built,and the distance characteristics,offset characteristics and frequency splitting phenomenon of the system are verified through multiple sets of experiments,and the control scheme proposed in this paper can improve the output power of the system through comparative experiments.and efficiency.The optimal transmission distance of the system can reach20 cm,and the maximum efficiency can reach more than 70%.Finally,thesis also designs a radiation-resistant enclosure for the wireless power transmission system,so that the system can work normally in the nuclear radiation environment. |
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