A Series of Dual-Frequency Hybrid Topologies With Vertical and Horizontal Misalignment Tolerance Performance in Inductive Power Transfer Systems

The outputs of the wireless power transfer (WPT) systems with the primary series (S) compensation are in reverse proportion to the mutual inductance, whereas those with the primary inductor capacitor capacitor (LCC) compensation are proportional. To enhance misalignment tolerance, this article proposes a family of novel dual-frequency integrated hybrid topologies that combine the S and LCC compensations. At one resonant frequency, the hybrid topology is equivalent to that with primary S compensation, and at the other resonant frequency, the LCC compensation. Four basic topologies are analyzed, and four basic integrated hybrid units are established. Based on these, eight available dual-frequency integrated hybrid topologies are derived. A mathematical model is developed for one of the integrated hybrid topologies, namely, the combination of the S-S and LCC-LCC topologies. An experimental prototype is constructed to test the misalignment tolerance capability of the proposed topology in both vertical and horizontal directions. The experimental results show that the proposed topology has smooth output characteristics with at least 90.3% efficiency. The proposed topology has better misalignment tolerance to a wide range of mutual inductance variations compared to the conventional topologies.