Increasing prevalence of dc sources and loads has resulted in dc distribution being reconsidered at a microgrid level. However, in comparison to ac systems, the lack of a natural zero crossing has traditionally meant that protecting dc systems is inherently more difficult-this protection issue is compounded when attempting to diagnose and isolate fault conditions. One such condition is the series arc fault, which poses significant protection issues as their presence negates the logic of overcurrent protection philosophies. This paper proposes the IntelArc system to accurately diagnose series arc faults in dc systems. Inte-lArc combines time-frequency and time-domain extracted features with hidden Markov models (HMMs) to discriminate between nominal transient behavior and arc fault behavior across a variety of operating conditions. Preliminary testing of the system is outlined with results showing that the system has the potential for accurate, generalized diagnosis of series arc faults in dc systems.

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This version is available at https://strathprints.strath.ac.uk/40245/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe 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 intellectual output.This paper is a preprint of a paper accepted by IET Electrical Systems in Transportation and is subject to Institution of Engineering and Technology Copyright. When the final version is published, the copy of record will be available at IET Digital Library. AbstractPower-dense, low-voltage marine electrical systems have the potential for extremely high fault currents. Superconducting fault current limiters (SFCLs) have been of interest for many years and offer an effective method for reducing fault currents. This is very attractive in a marine vessel in terms of the benefits arising from reductions in switchgear rating (and consequently size, weight and cost) and damage at the point of fault. However, there are a number of issues that must be considered prior to installation of any SFCL device(s), particularly in the context of marine applications. Accordingly, this paper analyses several such issues, including: location and resistance sizing of SFCLs; the potential effects of an SFCL on system voltage, power and frequency; and practical application issues such as the potential impact of transients such as transformer inrush. Simulations based upon an actual vessel are used to illustrate discussions and support assertions. It is shown that SFCLs, even with relatively small impedances, are highly effective at reducing prospective fault currents; the impact that higher resistance values has on fault current reduction and maintaining the system voltage for 1 Dr Nand Singh is now with Mott MacDonald Ltd., Croydon, CR0 2EE, U.K 2 other non-faulted elements of the system is also presented and it is shown that higher resistance values are desirable in many cases. It is demonstrated that the exact nature of the SFCL application will depend significantly on the vessel's electrical topology, the fault current contributio...

This version is available at https://strathprints.strath.ac.uk/34266/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe 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 intellectual output.This paper is a postprint of a paper submitted to and accepted for publication in IET Electric Systems in Transportation (EST) and is subject to IET copyright. AbstractThis paper describes the creation of a hardware-in-the-loop (HIL) environment for use in evaluating network architecture, control concepts and equipment for use within marine electrical systems. The environment allows a scaled hardware network to be connected to a simulation of a multi-megawatt marine diesel prime-mover, coupled via a synchronous generator. This allows All-Electric marine scenarios to be investigated without large-scale hardware trials. The method of closing the loop between simulation and hardware is described, with particular reference to the control of the laboratory synchronous machine which represents the simulated generator(s). The fidelity of the HIL simulation is progressively improved in this paper. Firstly a faster and more powerful field drive is implemented to improve voltage tracking. Secondly the phase tracking is improved by using two nested PIDA (proportional integral derivative acceleration) controllers for torque control, tuned using lambda-tuning. The HIL environment is tested using a scenario involving a large constant-power load step. This both provides a very severe test of the HIL environment, and also reveals the potentially adverse effects of constant-power loads within marine power systems.

The problem of exchanging data between two or more organizations in a format that is accessible and understandable by each is a universal problem. Furthermore, the problem of translating or accessing data in the correct format for applications using proprietary data formats is challenging. Legacy software applications may endure, for some time given, regulatory expenditure pressures on electricity system operators and these require data translators (importer/exporter) and access facilities. The basis of this paper is that the Electric Power Research Institute (EPRI) common information model (CIM) in eXtensible Markup Language (XML) represents the first stage in a revolution of data exchange and manipulation for power systems. This paper explores the problem of translating data in the CIM XML format to the required format for such legacy power system analysis applications. This paper discusses solutions to some of the challenges in data translation, and illustrates how these solutions can be implemented.Index Terms-CIM XML, power system data translation.