磁耦合谐振式无线电能传输功率与效率分析

Analysis on the Power and Efficiency of Magnetic Coupling Resonant Based on Wireless Power Transfer

通过电磁仿真得到了螺旋线圈在终端开路和终端短路两种不同馈电方式下相应的等效电路,基于螺旋线圈等效电路,运用等效电路理论,建立了螺旋线圈终端短路串电容两线圈结构模型。利用系统的等效电路,得到了系统输出功率和传输效率的数学表达式,并进一步分析了当系统谐振时,系统的输出功率及传输效率与互感系数、线圈分布电容、线圈内阻和负载电阻等参数之间的关系,从而给出了系统的参数优化方法,得到了最大功率输出时的最优互感值及传输效率随互感值变化而变化的趋势。设计制作了一套基于螺旋线圈终端短路串电容模型的磁耦合谐振式无线电能传输系统,通过实验验证了上述分析的正确性。

The two equivalent circuits with the helical coil fed by open-end and short-end via electromagnetic simula- tion are obtained.Based on the equivalent circuits of helical coil and the principle of equivalent circuits, the two coil structures based on the model of helical coil short-end series capacitance are carried on the system modeling.Using the system＇s equivalent circuit, the mathematical expression of transmission system＇s efficiency and output power are obtained.The further consideration of the relationship between parameters like the mutual inductance, winding capaci- tance ,the coil resistance and load resistance with the transmission system＇s efficiency and output power are taken while the system is in resonance ,which can provide methods of parameters optimization of the system.The optimal mutual inductance value is gotten, when output power is the most and the system＇s transmission efficiency changes trend with different mutual inductance values.Designing a set of magnetic coupling resonant wireless transmission sys- tem based on the model of helical coil about short-end series capacitance, and the experimental results demonstrate the foregoing analysis.