An LC Squared-Compensated Inductive Power Transfer System With Misalignment Tolerance and Constant-Current Output

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 (
LC
) squared-compensated topology based on three integrated and decoupled transmitting coils. The simple series compensation is adopted on the secondary side, forming an
LC
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.