Abstract:
In this article, a parity-time-symmetric CLLC coreless transformer (CLT) with a magnetic potential balance is proposed. Compared with the conventional CLTs, it nearly ach...Show MoreMetadata
Abstract:
In this article, a parity-time-symmetric CLLC coreless transformer (CLT) with a magnetic potential balance is proposed. Compared with the conventional CLTs, it nearly achieves a unit power factor without adding any power devices, reducing the circulating conduction loss and turn-off current on the primary side. First, a complete Hamiltonian formalism describing the total energy of the transformer is established in view of the concept of the variational inverse method. Its phase-space dynamics, pseudo-Hermitian, and spectral invariance are analyzed in combination with the symmetry. Second, the two-port characteristics of the proposed CLT are discussed. The analysis results indicate that it has the same magnetic potential balance as an ideal transformer and the equivalent magnetizing inductance is maximized, achieving load-independent voltage and current conversion ratios. Additionally, the control strategy and design of a 620 W 220 V-input and 48 V-output prototype are given. Finally, a detailed experimental comparison with the conventional CLT is performed, and the peak efficiency of the prototype is 97.4%.
Published in: IEEE Transactions on Industrial Electronics ( Volume: 71, Issue: 10, October 2024)