Superconducting fault current limiter application in a power-dense marine electrical system

Inst. for Energy & Environ., Univ. of Strathclyde, Glasgow, UK
IET Electrical Systems in Transportation 10/2011; 1(3):93 - 102. DOI: 10.1049/iet-est.2010.0053
Source: IEEE Xplore


Power-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 study 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 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 contribution of each of the generators, and the properties of the SFCL device, such as size, weight, critical current value and recovery time.

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    • "In power system, studies of SFCL are anticipated not only to limit fault current but also to develop stability of the system [5] [6]. Many studies have been carried out for the practical application of SFCL in electric power system in the past few years [7] [8] [9]. It includes current limiting characteristics of SFCL, optimal resistive value of SFCL to improve transient stability, optimal place to install the SFCL etc. "
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    ABSTRACT: Superconducting fault current limiter is an attractive electronic device to solve the problem of very high fault current in the power system. In this paper, the performance of enhanced system capacity with existing switchgear by superconducting fault current limiter is studied. At first, a resistive type SFCL is modeled in Simulink. A three phase system with a nominal capacity is designed and then it is replaced by higher capacity keeping switchgear unchanged. Finally, the SFCL is introduced in the higher capacity system. Fault current in this system is limited by SFCL to the level of the presented switchgear. Thus, it is revealed that the outstanding current limiting performance of SFCL can be used to limit the fault to the level of the existing switchgear if the system capacity is improved.
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    • "UPERCONDUCTING fault current limiters (SFCLs) offer an attractive solution to the problem of rising fault levels in highly power-dense electrical systems [1], [2], [3], [4]. However, for SFCLs to be effectively applied in power systems, it is important to understand their transient properties in order to coordinate their operation with power system protection devices and to ensure that, in a multiple SFCL application, that only the SFCL(s) closest to the fault location operate in order to avoid unnecessary disturbance to healthy elements of the power system. "
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