降低负载变化对无线电能传输功率的影响

The Influence of Reducing Load Change on Wireless Power Transfer Transmission Power

电动汽车锂离子电池的老化,充电过程中电池内阻的变化,负载温度的变化等均会引起WPT系统中负载电阻的变化,这会对系统功率传输的稳定性产生显著的影响。为解决这一问题,分析了负载电阻变化对功率传输的影响,并得到了一个能够降低负载变化对WPT传输功率影响的最优耦合范围。在此基础上,根据最优耦合范围确定了两线圈横向偏移、纵向偏移、同轴偏转的允许范围,并搭建实验平台进行验证,实验结果表明,在最优耦合范围内可将功率的变化值由0.6 kW缩减至0.05 kW以内。

Charging power is one of the hot issues in wireless power transfer(WPT)research.The aging of lithium batteries in electric vehicles,the change of battery internal resistance during charging,and the change of load temperature will all lead to the change of load resistance in the WPT system.Although these resistance changes are small,the power transmission of the system will have a significant decrease.To solve this problem,the influence of load resistance variation on the transmission power was analyzed,and an optimal coupling value was obtained to suppress the effect of load variation on WPT transmission power.On this basis,the allowable range of lateral deviation,longitudinal deviation and coaxial deflection of the two coils according to the optimal coupling value was determined,and an experimental platform was set up for verification.The experimental results showed that the variation value of power could be reduced from 0.6 kW to within 0.05 kW within the optimal coupling range.