Power source buffering using a triangular modular multilevel converter with energy storage

Abstract

iv As power systems throughout the world continue to utilize DC infrastructure within distributed generation solutions and microgrid designs, an effective DC-DC interfacing power electronic device must be developed for managing power flow and power quality levels between a system's increasingly diversified array of sources and loads. DC-DC power electronic interfaces are continuing to gain increased attention throughout many distribution applications, including the information and communication technology (ICT), electric vehicle, and renewable generation industries.The research effort described herein explores the use of a multi-port DC-DC modular multilevel converter interfacing a dual-input connection of a 380 VDC system and a 42.9 VDC/ 40.7 A photovoltaic panel with a 96 VDC output resistive load. Ultracapacitors are used to power-buffer the input signal and in this application, the inherently intermittent solar panel output. This technology represents the merits of utilizing a singular interfacing device to consolidate the flows between joint generation and load, while maintaining stable output power using a modular energy storage solution.This work details the operation and control of the DC-DC converter and its moduleinterfaced power buffering solution, as well as provide design methodologies for the system described.