Modelling of A Planar Omnidirectional Wireless Power Transfer System

Recently, omnidirectional wireless power transfer ( WPT) has gained widespread popularity since 2010s especially in consumer electronics application benefiting from ease of integration with furniture. In such applications, angular misalignment occurs frequently. Obviously, it will affect the stable operation of system significantly. However, the mechanism is not investigated accurately. In other words, the modelling and effects under angular misalignment are not investigated completely. Targeting at this, this article proposes a planar omnidirectional wireless power transfer system with three sets of planar coils. Afterwards, the complete modelling process is conducted for the planar omnidirectional WPT system under angular misalignment and N-s effect is investigated. Afterwards, the simulation is conducted to verify the correctness of the modelling process. Finally in the experiment, three sets of coils are fabricated and the transfer efficiency are measured under orientation and angular misalignment at 6.78MHz. When charging the mobile phone and electronic watch receivers, the overall efficiency is 69%78% and 55%-65%, considering the orientation and angular misalignment.