Optimal Design of Quadrature-Shaped Pickup for Omnidirectional Wireless Power Transfer

Omnidirectional wireless power transfer (WPT) technology is a brand-new way of energy supply which is able to transfer power to the pickup unit wherever it locates around the transmitter. One of the most important purposes of such a system is to ensure the pickup unit can obtain enough energy evenly at all directions in 3-dimensional space around the transmitter [1]. However, there exists some special positions where the received power decreases to a lower level, such as the position as Fig.1 (a)depicts. Taking the current limit of transmitting coils into consideration and avoiding the input excitation beyond the restriction, this paper proposes a quadrature-shaped pickup which can effectively enhance the ability of capturing power at specific positions instead of just increasing the input. The optimized load power and transmission efficiency are able to be achieved according to different requirements by adjusting the key size variable.