用于动态无线电能传输的新型线圈结构设计

Design of a novel coil structure for dynamic wireless power transfer

摘要:

为改善动态无线电能传输(dynamic wireless power transfer,DWPT)过程中,因发射阵列之间摆放间距过大而产生的输出电压和输出功率的波动问题,提出一种新型发射结构。首先,在BPP(bipolar pad)线圈结构基础上,将主发射(domination transmitter,Dtx)线圈与补偿(compensation,Cx)线圈串联组成一个发射段,并对DWPT系统采用分段控制,以减小损耗;其次,采用解耦电容解耦Dtx线圈与Cx线圈,并分析了系统的电路原理;然后,利用Ansys Maxwell有限元分析软件对耦合结构进行优化设计,并选择最佳的切换位置,以减小功率的波动;最后,搭建实验平台以验证结构的可行性。实验结果表明:新型磁耦合结构输出功率的波动为3.9%,输出电压的波动为2.9%,与改进前的耦合结构相比,输出功率的波动降低了15.8%,输出电压的波动降低了7.6%；在相邻Dtx线圈的过渡区域中,与改进前的耦合结构相比,输出功率提高了33.8%,且系统传输效率稳定在88%左右。所提出的新型发射结构有助于减小移动过程中输出电压和输出功率的波动,可为磁耦合结构的设计与应用提供理论支持。

Abstract:

To improve the voltage and power fluctuations arising from large spacing between the trarsmitting arrays in the dynamic wireless power transfer (DWPT) systems, this paper proposes a novel transmitting structure. Firstly, based on the bipolar pad (BPP) coil structure, the domination transmitter (Dtx) coil and the compensation (Cx) coil are connected serially to form a transmission segment. The DWPT system adopts segment control to minimize losses. Secondly, decoupling capacitors are used to decouple the Dtx coil and Cx coils, and the circuit principles of the system are analyzed. Then, the coupling structure is optimized and designed using Ansys Maxwell finite element analysis software, and the optimal switching positions are selected to minimize power fluctuations. Finally, an experimental platform is set up to validate the feasibility of the structure. The experimental results show that the power fluctuation of the new magnetic coupling structure is 3.9%, and the voltage fluctuation is 2.9%. Compared with the previous coupling structure, the power fluctuation has decreased by 15.8%, and the voltage fluctuation has decreased by 7.6%. In the transition region between adjacent Dtx coils, compared with the improved coupling structure, the power output has increased by 33.8%, with the system′s transmission efficiency stabilizing around 88%. The proposed novel transmitting structure in this paper helps reduce the fluctuations in output voltage and power during the movement process, and provides a theoretical support for the design and application of magnetic coupling structures.