A Reconfigurable Multiport Converter for Integrated PV/EV/Battery Systems

Abstract

Power conversion is crucial for the global shift towards decarbonising energy systems. Maximizing efficiency in component usage, particularly in power conversion products, is essential. Our proposed reconfigurable multiport converter aims to improve utilization of the power interface along with associated measurement and data acquisition. The purpose of this reconfigurable circuit is to integrate multiple energy sources, including PV, electric vehicle storage, home battery systems, and provide a connection to the AC grid, where all ports are capable of bidirectional power flow. Primary side devices, inductors and switches, serve multiple purposes depending on the operating mode e.g., four of the eight primary side switches are either modulated or used as connectors. Similarly, the primary bridge can act to transfer power across the transformer or function as a synchronous switch. Our contributions to this area include developing a unified power electronic interface for integration of multiple energy sources, reconfigurability of the circuit into controllable power conversion topologies and sharing key components for increased utilization. This design offers several advantages, including reduced measurement, sensing, and communication requirements, enhanced operational flexibility, alternate power flow paths, minimized magnetic components, and the use of a single microcontroller for the entire power electronic interface. The proposed converter is designed and verified through experimental tests with a 1-kW, 200 kHz laboratory scale hardware prototype. Experiments demonstrated the ability of the circuit to reconfigure in to controllable topologies to achieve various power flow modes across different ports of the circuit that are PV-to-EV, Grid-to-EV, PV-to-battery, PV-to-grid, PV/battery-to-EV and PV/grid-to-EV. Experimental investigation of the dynamic response during mode transitions verified stability and robustness of the proposed converter.