Wireless power transmission region stands out for its convenience in applications where several terminals or movable terminals need to be charged. The conventional single coil excited charging region has the drawback of distance and angle limitation. To overcome the shortcoming

a charging region constructed by four excited coils is proposed. This four exciting coils configuration can not only increase the transmission distance

but also weaken the sensitivity to angle change. By regarding the excited coil as a magnetic pole

four winding connection types of the four excited coils are put forward. By both theoretical analysis and software simulation

magnetic field distributions of these four winding connection types are studied and S-S-N-N is finally selected as the winding connection type. The equivalent circuit for this configuration is derived and the parameter design method is further presented. Finally

a 0.8 m×0.8 m×0.8 m wireless power transmission region with four exciting coils via magnetic resonances is fabricated in the lab and the experimental results can verify the correctness of parameter design and the effectiveness of the proposed four coil excited charging region. This work is supported by National Natural Science Foundation of China (No. 51077069)

Jiangsu Provincial Natural Science Foundation of China (No. BK2009372) and Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) of China (No. 20103218110013).