Proposal of Integrated Circuit Structure with Boost Motor Drive and On-board Charging for a 48V Battery System

An integrated circuit structure is proposed for a 48V power system. This paper discusses the operating principle of the proposed circuit and the control algorithms. The circuit structure integrates a boost motor drive with a three-phase AC on-board charger (OBC). An integrated magnetic device (IMD) that consists of two functionalities is used in the boost converter, where the IMD is performed as a boost inductor during motor drive and also performed as an isolated transformer during AC charging, respectively. Then a matrix converter is used in the OBC to reduce the capacitive component. As a result, the overall circuit structure is only consisting of one capacitive and two inductive components (IMD and grid inductor). A 3kW A4 size prototype was developed and tested in order to validate the performance of the proposed circuit. From the results, the conversion efficiency achieves 94% for boost motor drive and 93% for a three-phase AC charging.