Multi-port, Bi-directional Contactless Connector for the Interface of Modular Portable Battery System

This article presents a multiport, bidirectional, contactless connector based on the inductive power-transfer technology. The unique structure of the axially gapped cylindrical core facilitates the proposed contactless connector to control the output of multiple low-voltage batteries in parallel, thereby balancing the state of charge. Axial gaps in the proposed transformer facilitate realization of accurate power distribution via multiple-input/output phase-shift control. Investigation performed on a prototype of the proposed connector revealed realization of 95% efficiency at $\mathrm{\pm }$ 1 kW, 3 mm contactless power transfer along with a power-balancing function between a 300 V output and six of 50 V inputs. The proposed technology is expected to enhance the safety and reliability of large capacity, high-power batteries employed in electrical-mobility and renewable-energy systems.