Testing Impedance Based Fault Location Using Orthogonal Components For Different Fault Parameters

To ensure the mission implementation of Autonomous Underwater Vehicles (AUVs), faults occurring on actuators should be detected and located promptly; therefore, reliable control strategies and inputs can be effectively provided. In this paper, faults occurring on the propulsion and attitude control systems of a torpedo-shaped AUV are analyzed and located while fault features may induce confusions for conventional fault localization (FL). Selective features of defined fault parameters are assorted as necessary conditions against different faulty actuators and synthesized in a fault tree subsequently to state the sufficiency towards possible abnormal parts. By matching fault features with those of estimated fault parameters, suspected faulty sections are located. Thereafter, active FL strategies that analyze the related fault parameters after executing purposive actuator control are proposed to provide precise fault location. Moreover, the generality of the proposed methods is analyzed to support extensive implementations. Simulations based on finite element analysis against a torpedo-shaped AUV with actuator faults are carried out to illustrate the effectiveness of the proposed methods.

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Application of Estimation of Model Parameters for Protective Automation of Transmission Lines

10.7250/9789934224966 ◽

2020 ◽

Author(s):

◽

Ivars Zālītis

Keyword(s):

Communication Networks ◽

Transmission Lines ◽

Fault Location ◽

Single Phase ◽

Model Parameters ◽

Distance Protection ◽

Long Distance ◽

Fault Parameters ◽

Automatic Reclosing ◽

Available Information

Transmission lines are indispensable part of power transmission system, which are highly exposed to fault risk factors of environmental and anthropogenic nature. Therefore, protection and control have to be robust and reliable as possible. Distance protection and some of fault location methods, used today for transmission lines, operate within a limited scope of available information that can result in errors and incorrect operation, especially when faults have high transient resistance. In order to overcome these drawbacks of one-terminal-based distance protection and fault locations methods it is proposed to use a technique of estimation of unknown power system model parameters, solving these problems as an optimisation tasks. The scope of available information is extended by incorporation of all measurements, available from the controlled substation, thus eliminating necessity of long-distance communication networks, and by a separate stage of parameter estimation during the pre-fault regime, which is similar to estimation of fault parameters but operates with a nonlinear model reflecting the influence of governors. The Thesis provides modelling tools for both pre-fault and different fault regimes based on symmetrical component and topological modelling methods to accommodate the increased measurement scope. The proposed method was extensively tested considering two different strategies for selection of measured parameters used by the optimisation. The proposed method and its results is not limited to the fault location or distance protection, as the developed technique was also used to create a new method of an adaptive single-phase automatic reclosing algorithm. The proposed method can be used as a base for creation of robust algorithms and devices for the fault location, distance protection and single-phase automatic reclosing. It can also be modified or directly implemented for different transmission line automation and protection problems. The modelling tools described in the Thesis can be used for a further analysis and development of relay protection and automation.

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Co-seismic deformation, field observations and seismic fault model of the Oct. 30, 2020 Mw=7.0 Samos earthquake, Aegean Sea

10.5194/egusphere-egu21-14595 ◽

2021 ◽

Author(s):

Panagiotis Elias ◽

Athanassios Ganas ◽

Pierre Briole ◽

Sotiris Valkaniotis ◽

Javier Escartin ◽

...

Keyword(s):

Fault Location ◽

Normal Fault ◽

Aegean Sea ◽

Rock Falls ◽

Seismic Fault ◽

Fault Parameters ◽

Northern Shore ◽

Loose Sediments ◽

Dip Angle ◽

Seismic Deformation

<p>On 30 October 2020 11:51 UTC a large Mw = 7.0 earthquake occurred offshore of the island of Samos, Greece. In this contribution we present the characteristics of the seismic fault (location, geometry, geodetic moment) as inferred from the processing of geodetic data (InSAR and GNSS). We use the InSAR displacement data from Sentinel-1 interferograms (ascending orbit 29 and descending 36) and the GNSS offsets from eleven (11) permanent stations in Greece and Turkey to invert for the fault parameters. Our inversion modeling indicates the activation of a normal fault north of Samos with a length of 32 km, width of 17 km, average slip of 2.1 m, a moderate dip-angle (37&#176;) and with a dip-direction towards North. The inferred fault is located adjacent to Samos northern coastline, with the top of the slip ~1 km below surface, and ~2 km off-shore at its closest to the island. The earthquake caused the permanent uplift of the island up to 10 cm with the exception of a coastal strip along the NE part of the northern shore (near Kokkari) that subsided 2-6 cm. The effects of the earthquake included liquefaction, rock falls, rock slides, road cracks and deep-seated landslides, all due to the strong ground motion and associated down-slope mobilization of soil cover and loose sediments.</p>

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A Quaternary fault database for central Asia

Natural Hazards and Earth System Science ◽

10.5194/nhess-16-529-2016 ◽

2016 ◽

Vol 16 (2) ◽

pp. 529-542 ◽

Cited By ~ 20

Author(s):

Solmaz Mohadjer ◽

Todd Alan Ehlers ◽

Rebecca Bendick ◽

Konstanze Stübner ◽

Timo Strube

Keyword(s):

Seismic Hazard ◽

Central Asia ◽

Fault Location ◽

Earthquake Risk ◽

Economic Damage ◽

Online Database ◽

Slip Rates ◽

Fault Parameters ◽

Interactive Map ◽

Fault Information

Abstract. Earthquakes represent the highest risk in terms of potential loss of lives and economic damage for central Asian countries. Knowledge of fault location and behavior is essential in calculating and mapping seismic hazard. Previous efforts in compiling fault information for central Asia have generated a large amount of data that are published in limited-access journals with no digital maps publicly available, or are limited in their description of important fault parameters such as slip rates. This study builds on previous work by improving access to fault information through a web-based interactive map and an online database with search capabilities that allow users to organize data by different fields. The data presented in this compilation include fault location, its geographic, seismic, and structural characteristics, short descriptions, narrative comments, and references to peer-reviewed publications. The interactive map displays 1196 fault traces and 34 000 earthquake locations on a shaded-relief map. The online database contains attributes for 123 faults mentioned in the literature, with Quaternary and geodetic slip rates reported for 38 and 26 faults respectively, and earthquake history reported for 39 faults. All data are accessible for viewing and download via http://www.geo.uni-tuebingen.de/faults/. This work has implications for seismic hazard studies in central Asia as it summarizes important fault parameters, and can reduce earthquake risk by enhancing public access to information. It also allows scientists and hazard assessment teams to identify structures and regions where data gaps exist and future investigations are needed.

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A Quaternary Fault Database for Central Asia

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-3-5599-2015 ◽

2015 ◽

Vol 3 (9) ◽

pp. 5599-5632

Author(s):

S. Mohadjer ◽

T. A. Ehlers ◽

R. Bendick ◽

K. Stübner ◽

T. Strube

Keyword(s):

Seismic Hazard ◽

Central Asia ◽

Fault Location ◽

Earthquake Risk ◽

Economic Damage ◽

Online Database ◽

Slip Rates ◽

Fault Parameters ◽

Interactive Map ◽

Fault Information

Abstract. Earthquakes represent the highest risk in terms of potential loss of lives and economic damage for Central Asian countries. Knowledge of fault location and behavior is essential in calculating and mapping seismic hazard. Previous efforts in compiling fault information for Central Asia have generated a large amount of data that are published in limited-access journals with no digital maps publicly available, or are limited in their description of important fault parameters such as slip rates. This study builds on previous work by improving access to fault information through a web-based interactive map and an online database with search capabilities that allow users to organize data by different fields. The data presented in this compilation include fault location, its geographic, seismic and structural characteristics, short descriptions, narrative comments and references to peer-reviewed publications. The interactive map displays 1196 fault segments and 34 000 earthquake locations on a shaded-relief map. The online database contains attributes for 122 faults mentioned in the literature, with Quaternary and geodetic slip rates reported for 38 and 26 faults respectively, and earthquake history reported for 39 faults. This work has implications for seismic hazard studies in Central Asia as it summarizes important fault parameters, and can reduce earthquake risk by enhancing public access to information. It also allows scientists and hazard assessment teams to identify structures and regions where data gaps exist and future investigations are needed.

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Failure Analysis Of Buried Gas Pipelines Crossing Seismic Faults

Academic Perspective Procedia ◽

10.33793/acperpro.03.02.2 ◽

2020 ◽

Vol 3 (2) ◽

pp. 781-790

Author(s):

M. Rizwan Akram ◽

Ali Yesilyurt ◽

A.Can. Zulfikar ◽

F. Göktepe

Keyword(s):

Ground Deformation ◽

Warning System ◽

Strike Slip ◽

Gas Pipelines ◽

Steel Pipes ◽

Seismic Fault ◽

Fault Parameters ◽

Dip Angle ◽

Permanent Ground Deformation ◽

Recent Earthquakes

Research on buried gas pipelines (BGPs) has taken an important consideration due to their failures in recent earthquakes. In permanent ground deformation (PGD) hazards, seismic faults are considered as one of the major causes of BGPs failure due to accumulation of impermissible tensile strains. In current research, four steel pipes such as X-42, X-52, X-60, and X-70 grades crossing through strike-slip, normal and reverse seismic faults have been investigated. Firstly, failure of BGPs due to change in soil-pipe parameters have been analyzed. Later, effects of seismic fault parameters such as change in dip angle and angle between pipe and fault plane are evaluated. Additionally, effects due to changing pipe class levels are also examined. The results of current study reveal that BGPs can resist until earthquake moment magnitude of 7.0 but fails above this limit under the assumed geotechnical properties of current study. In addition, strike-slip fault can trigger early damage in BGPs than normal and reverse faults. In the last stage, an early warning system is proposed based on the current procedure.&nbsp;

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