Design of a Low-Voltage High-Power DC Power Supply for Microbial Electrochemical Synthesis

Abstract

This Master’s Thesis is established to design an optimal low-voltage high-power DC power supply which can feed a biochemical system consisting of a microbial electrolysis cell, which further is connected to an existing anaerobic digestion plant. The complete system is called a bioelectrochemical system, where the purpose is to increase the amount of methane by reducing the amount of carbon dioxide in the biochemical system. The objectives for the thesis are mainly to design a power supply that can be used for a laboratory scale setup. In addition, a minor evaluation of the scalability for a larger pilot setup will be performed, as well as an investigation of the availability of commercial power supplies suitable for a laboratory scale system. There have been performed several methods to obtain the goal of the thesis, including a literature review, and modelling and simulation of different power supply models in Simulink. The thesis concludes that a switch mode DC power supply would be a proper choice to implement in the bioelectrochemical system due to a high efficiency around 90 %, and with great regulation opportunities. More precisely, the design of the half-bridge DC-DC converter with electrical isolation, which had a series configuration, will be the recommended choice for an optimal low-voltage highpower DC power supply which can be connected to the biochemical system.