基于频率切换实现恒流/恒压输出的电场耦合无线电能传输系统

Electric-field Coupled Wireless Power Transfer System With Constant Current/Constant Voltage Output Characteristics Based on Frequency Switching

电场耦合无线电能传输(electric-field coupled wireless power transfer,EC-WPT)技术的实际应用中,有些用电设备需要系统具有不同的恒定输出特性(恒流/恒压),即系统输出电压或输出电流与负载解耦,此外,系统还需具备在恒流、恒压模式间按需切换的功能。针对该需求,基于LC-CLC谐振网络提出1种具有恒流/恒压输出特性的EC-WPT系统,分析LC-CLC谐振网络特性,推导恒流/恒压输出特性的实现条件以及恒流频率和恒压频率的计算方法,并给出系统参数设计方法,分析系统对工作频率的敏感性。最后通过仿真和实验验证所提出的EC-WPT系统恒流/恒压输出特性及其参数设计方法的正确性和有效性。实验结果表明所提出的系统在输入电压恒定的不同负载工况下分别实现2 A的恒流输出以及96 V的恒压输出,其最大传输效率分别为87.83%及88.17%。

In the practical application of electric-field coupled wireless power transfer(EC-WPT)technology,some electrical equipment requires the system to have different constant output characteristics(constant current/constant voltage),that is,the system output voltage or output current is decoupled from the load.In addition,the system also needs to have the function of switching between constant current and constant voltage modes on demand.To meet this requirement,this paper proposes an EC-WPT system with constant current/constant voltage output characteristics based on LC-CLC resonant network,analyzes the characteristics of LC-CLC resonant network,deduces the realization conditions of constant current/constant voltage output characteristics and the calculation methods of constant current frequency and constant voltage frequency,gives the design method of system parameters,and analyzes the sensitivity of the system to the working frequency.Finally,the correctness and effectiveness of the constant current/constant voltage output characteristics and parameter design method of the EC-WPT system proposed in this paper are verified by simulation and experiments.The experimental results show that the proposed system achieves constant voltage output of 96 V and constant current output of 2 A under different load conditions with constant input voltage,and the maximum transmission efficiency is 87.83%and 88.17%,