Behavior of HV cable at short circuit

In order to improve the practice in the operation and maintenance of high voltage (HV) cables, this paper proposes a fault location method based on the monitoring of cable sheath currents for use in cross-bonded HV cable systems. This method first analyzes the power–frequency component of the sheath current, which can be acquired at cable terminals and cable link boxes, using a Fast Fourier Transform (FFT). The cable segment where a fault occurs can be localized by the phase difference between the sheath currents at the two ends of the cable segment, because current would flow in the opposite direction towards the two ends of the cable segment with fault. Conversely, in other healthy cable segments of the same circuit, sheath currents would flow in the same direction. The exact fault position can then be located via electromagnetic time reversal (EMTR) analysis of the fault transients of the sheath current. The sheath currents have been simulated and analyzed by assuming a single-phase short-circuit fault to occur in every cable segment of a selected cross-bonded high voltage cable circuit. The sheath current monitoring system has been implemented in a 110 kV cable circuit in China. Results indicate that the proposed method is feasible and effective in location of HV cable short circuit faults.

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Behavior of HV cable of power supply at short circuit and related phenomena

IEEE Transactions on Dielectrics and Electrical Insulation ◽

10.1109/tdei.2013.6451338 ◽

2013 ◽

Vol 20 (1) ◽

pp. 28-33 ◽

Cited By ~ 4

Author(s):

Alex Pokryvailo ◽

Cliff Scapellati

Keyword(s):

Power Supply ◽

Short Circuit ◽

Hv Cable

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Behavior of HV cable at short circuit and related phenomena

2012 IEEE International Power Modulator and High Voltage Conference (IPMHVC) ◽

10.1109/ipmhvc.2012.6518711 ◽

2012 ◽

Cited By ~ 1

Author(s):

Alex Pokryvailo ◽

Cliff Scapellati

Keyword(s):

Short Circuit ◽

Hv Cable

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Structural Imperfections in thin Oxide Films Formed on Some Fe- and Ni-Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069545 ◽

1970 ◽

Vol 28 ◽

pp. 510-511

Author(s):

L. P. Lemaire ◽

D. E. Fornwalt ◽

F. S. Pettit ◽

B. H. Kear

Keyword(s):

Oxide Scale ◽

Oxidation Process ◽

Short Circuit ◽

Protective Oxide ◽

Protective Oxide Scale ◽

Thin Oxide Films ◽

Diffusion Paths ◽

Oxidation Resistant ◽

Structural Imperfections ◽

Short Circuit Diffusion

Oxidation resistant alloys depend on the formation of a continuous layer of protective oxide scale during the oxidation process. The initial stages of oxidation of multi-component alloys can be quite complex, since numerous metal oxides can be formed. For oxidation resistance, the composition is adjusted so that selective oxidation occurs of that element whose oxide affords the most protection. Ideally, the protective oxide scale should be i) structurally perfect, so as to avoid short-circuit diffusion paths, and ii) strongly adherent to the alloy substrate, which minimizes spalling in response to thermal cycling. Small concentrations (∼ 0.1%) of certain reactive elements, such as yttrium, markedly improve the adherence of oxide scales in many alloy systems.

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