Design of an LCC-SP Compensated WPT System and Parameters Tuning Method for Misalignment Condition

Abstract

Based on the primary side with LCC compensation and the secondary side with a series capacitor and a parallel capacitor, the mathematical model of LCC-SP compensation topology for wireless power transfer (WPT) system is established. The impedance condition and the constant current output characteristic of the newly proposed topology are studied, followed by a detailed derivation of compensation parameters based on the discussion about resonant tank. The realization of zero voltage switching (ZVS) and reactive power demand are discussed by theoretical deduction and numerical simulation. Theoretical analysis shows that the appropriate detuned resonant tank is advantageous in performance, especially the smoothing of current output to variation of coupling coefficient. Theoretical analysis indicates that the proposed system has four attractive characteristics: constant current output, easy achievement of ZVS, higher design freedom, high misalignment tolerance. Finally, the WPT prototype with the LCC-SP compensation network is built and tested. The experimental results match well with the calculations, validating the correctness of theoretical analysis.