Proposal and Verification of Two-Layer Three-Phase Contactless Power Transformer

Abstract

A two-layer three-phase contactless power transformer that has steady power-transfer characteristics, even at rotational misalignments, is proposed. The proposed transformer has three-phase coils arranged on each layer. The coils on the lower layer are arranged with a rotational shift by π with respect to those on the upper layers. Moreover, the coils on the lower layer are turned in the opposite direction to those on the upper layer. On the basis of the prototype of the proposed transformer, the equivalent model is derived. Using this model, the behavior of the proposed transformer is compared with that of the conventional three-phase transformer and is theoretically assessed. Experiments using the prototype confirm that the proposed transformer can output steady power and achieve good efficiency independent of the rotational misalignment. Moreover, the power transfer characteristics at the horizontal misalignments of the proposed transformer are measured and assessed.