2017) Electro-thermal analysis of power converter components in low-voltage DC microgrids for optimal protection system design. IEEE Transactions on Smart Grid. ISSN 1949-3053 , http://dx. The Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's

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... intellectual output. Abstract--Bidirectional power converters are considered to be key elements in interfacing the low voltage dc microgrid with an ac grid. However to date there has been no clear procedure to determine the maximum permissible fault isolation periods of the power converter components against the dc faults. To tackle this problem, this paper presents an electro-thermal analysis of the main elements of a converter: ac inductors, dc capacitors and semiconductors. In doing this, the paper provides a methodology for quantifying fault protection requirements for power converter components in future dc microgrids. The analysis is performed through simulations during normal and fault conditions of a low voltage dc microgrid. The paper develops dynamic electrothermal models of components based on the design and detailed specification from manufacturer datasheets. The simulations show the impact of different protection system operating speeds on the required converter rating for the studied conditions. This is then translated into actual cost of converter equipment. In this manner, the results can be used to determine the required fault protection operating requirements, coordinated with cost penalties for uprating the converter components. Index Terms-- Microgrid, DC fault current, AC-DC power conversion, thermal design, power semiconductor diode switches, thermal stress, fault protection requirements. Graeme M. Burt (M'95) received the B.Eng. degree in electrical and electronic engineering from the University of Strathclyde, Glasgow, UK, in 1988, and the Ph.D. degree from the University of Strathclyde in 1992, following research into fault diagnostic techniques for power networks. He is currently a Director of the Institute for Energy and Environment at the University of Strathclyde, where he also directs the University Technology Centre in Electrical Power Systems sponsored by Rolls-Royce. He is a professor of electrical power engineering, and has research interests in the areas of: integration of distributed generation; power system modelling, real-time simulation, protection and control; microgrids and more-electric systems.