变参数变结构条件下电动汽车无线充电系统的关键技术研究

Inductive power transfer (IPT) system, which omits the charging cable, is a safer and more reliable technology for electric vehicles charging compared with the traditional plug-in solutions. With IPT technology, it is easy to realize automatic charging and meet the demands of the electric vehicles charging in the future. This project will perform an in-depth research on the key technologies of the IPT system under parameters variations and structures variations. The main research contents consist of three parts, compensation schemes, magnetic field excitation technologies, and control strategies. Compensations will be categorized to several types. The characteristics of the output with respect to change in the extent of coupling and load for the various types of compensation schemes will be clarified and the appropriate choice of compensation schemes for use in condition of wide variation of parameters will be identified. The magnetic field distribution of different windings will be analyzed and then a magnetic field excitation technology based on multiple windings will be proposed to solve the zero power transfer capability problem. Considering the technical characteristics of battery charging, a cascaded system and a high reliability control strategy will be provided. By solving the practical problem, this project will promote the marketability of electric vehicles.

感应式无线充电技术相较于传统接触式充电技术，省略了充电电缆，安全可靠、易于实现无人自动充电，符合未来电动汽车充电需求。本项目针对系统在参数变化下的优化控制困难、结构变化下的功率输出困难，围绕系统的三大关键技术：补偿网络、磁场激励技术、控制策略，展开研究。对补偿网络分类，揭示输出变参数敏感度受电路参数影响的本质原因，给出变参数下补偿网络的最佳设计方法；分析不同线圈的磁场分布规律，通过对复合线圈磁场激励技术的研究，解决磁结构失配导致功率传输能力丧失的问题；针对动力电池充电的技术特点，提出可实现恒流-恒压输出的系统架构及不需实时无线通信的原边控制方法，实现变参数工况下稳定可靠的供电。本项目的研究有助于解决电动汽车无线充电面临的实际问题，对电动汽车市场化推广起到促进作用。

补偿网络、磁场激励技术和控制是影响无线充电系统特性的三大关键技术。本项目分别针对这三大技术展开了研究。通过对补偿网络进行了新的分类研究，揭示了为获得内在的变参数条件下输出波动小的特性，补偿网络应具有的特性——即在完全补偿点处可同时实现输出增益与负载及耦合均无关、且能工作在输出相对耦合变化的非单调区间。更进一步提出了可同时实现输出可调和输入ZPA的极简三电容补偿方案——输出恒压值任意可调的S/SP补偿及输出恒流值任意可调的S/PS补偿，解耦了输入输出关系与变压器物理参数之间的关系，为系统效率、补偿成本、输出波动的优化提供了空间。研究了不同线圈的磁场分布规律，提出了基于复合线圈的磁场激励技术，以解决磁结构失配造成的功率传输能力丧失的问题。提出了不依赖实时无线通信的可实现恒流/恒压输出的原边控制方法，实现了变参数下系统的稳定可靠。项目的研究为变参数变结构下无线充电系统的设计提供了理论基础和实践经验。