An <i>LC</i> Squared-Compensated Inductive Power Transfer System With Misalignment Tolerance and Constant-Current Output
Yiming Zhang, H. Tang, Zhiwei Shen, Yizhan Zhuang, Zhongqi Li
Abstract
Inductive power transfer enjoys the advantages of convenience and adaptability to various application scenarios. However, the coil misalignment normally cannot be avoided in practical applications, which can cause a dramatic decline of the mutual inductance and a sharp fluctuation of the output. To solve this issue, this article proposes an inductor–capacitor ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> ) squared-compensated topology based on three integrated and decoupled transmitting coils. The simple series compensation is adopted on the secondary side, forming an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> squared series topology with a constant-current (CC) output. The receiving coil has couplings with the first and third transmitting coils. Thus, the output is related to the two mutual inductances, which can be optimized for a smooth output against misalignment with a proper design of the magnetic couplers. The mathematical model is established and analyzed. The experimental results obtained from the prototype reveal that the output fluctuates less than 6% from the central to the boundary positions. Also, a CC output independent of the load is realized. Compared with previous methods, the proposed method is a low-cost solution to achieve misalignment tolerance.