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Showing 1 to 20 of 23 for “"Geomagnetically Induced Currents"”.
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Impact of Geomagnetically Induced Currents on Power Transformers
This thesis deals with the impact of Geomagnetically Induced Current (GIC) on power transformers in electrical power systems. A simulator to calculate the flows of GIC in an electrical power network, based on an assumed or measured induced geoelectric potential is proposed. This simulator includes …
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Geomagnetically induced currents and their effect on power systems
… induce a change in the Earth’s magnetic field. Geomagnetically induced current (GIC) then enters the power grid and causes unusual real and reactive power flows, voltage fluctuations, frequency shifts, undesired relay operations, high third-harmonic currents and telemetry and supervisory alarm …
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Operational modelling of geomagnetic fields and geomagnetically induced currents
Geomagnetically induced currents (GICs) have long been known to affect power systems adversely. Modelling these GICs usually involves consideration of a chain of coupled systems. The scope of the modelling chain spans multiple disciplines, from solar physics through to geophysics and power …
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Multifractal Analysis of Geomagnetically Induced Currents using Wavelet Leaders
… disturbing communication systems, and inducing currents on pipelines and electric power lines, which in turn may cause increased corrosion or blackouts, among other effects. In this dissertation, we analyze measured electrical signals provided to us by the Finnish Meteorological Institute, which …
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Data-driven prediction of geomagnetically-induced currents in power lines
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2023-08-01
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Three-phase five limb transformer responses to geomagnetically induced currents
Geomagnetically induced currents (GIC) are quasi-DC currents that result from space weather events arising from the sun. The sun ejects hot plasma in a concept termed ‘coronal mass ejections' which is directed towards the earth. This plasma interferes with the magnetic field of the magnetosphere …
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Effects of geomagnetically induced currents on power transformers and reactors
Bibliography: leaves 106-109.
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Geomagnetically induced currents and its presence in the Eskom transmission network
… into the possible existence and occurrence of Geomagnetically Induced Currents (GICs) in the Eskom MTS. The project commenced in January 1999 and is a joint collaboration between Eskom, the University of Cape Town and EPRI. Eskom has been aware since about 1990, that occasional severe …
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Estimation of Geomagnetically Induced Currents (GICS) in the Namibian transmission network
Geomagnetically Induced Currents (GICs) have become a matter of concern not only to networks located in high magnetic latitude regions but also in networks located in mid-latitude regions. GICs pose a threat of transmission equipment damage which could lead to short power interruptions and …
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Saturation Effects in 3p3L Power Transformers due to Geomagnetically Induced Currents
Geomagnetically induced currents (GIC's) caused by solar storms or other sources of dc excitation can impact the normal operation of power transformers in transmission networks. The impact is caused by the dc current introduced into the windings of a transformer energised with ac, which leads to a …
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Geomagnetically induced currents (GIC) in large power systems including transformer time response
Geomagnetically induced currents (GIC) are the result of changing geomagnetic fields which are a consequence of a geomagnetic disturbance (GMD). The flow of GIC through transmission lines and transformers across the power network could have severe consequences, if the magnitudes of the GIC are high …
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Development of a finite element matrix (fem)three-phase three-limb transformer model for Geomagnetically Induced Currents (GIC) experiments
Geomagnetically Induced Currents (GIC) have been a growing concern within power system operators and researchers as they have been widely reported to lead to power system related issues and material damage to system components like power transformers. In power transformers, GIC impacts are …
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High-Resolution Time-Synchronized Monitoring and Anomaly Detection in Modern Distribution System
… detector for transformer saturation caused by geomagnetically induced currents (GICs) is developed using synchronized harmonic real power derived from the harmonic synchrophasors estimated by the algorithm in Chapter 2. This approach offers a more cost-efficient alternative to direct GIC …
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Power transformer magnetization under GIC/GMD
Geomagnetically induced currents (GIC) could saturate a transformer core. Two significant effects are the abnormal stray flux in transformers and extremely large harmonic contents in excitation currents, which can lead to serious equipment damage and power system misoperation. Such incidents have …
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Duality derived topological model of single phase four limb transformers for GIC and DC bias studies
… geo-electric fields in the Earth that drive geomagnetically induced currents through the earthed neutrals of transformers and through power transmission networks. The flow of these currents causes the magnetic cores of transformers to half-wave saturate. Saturated transformers pose problems …
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Design of Low-Frequency acGIC Voltage Stability Laboratory Protocol
Geomagnetically Induced Currents (GICs) are formed as a direct consequence of space weather phenomena and have detrimental effects on power systems. GICs enter the power system through transformers' grounded neutrals, causing an array of problems ranging from transformer overheating to voltage …
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Synchronous generator and excitation system response to GIC
… physicists, and power engineers. The resultant Geomagnetically Induced Currents (GIC) lead to periodic part wave saturation of transformers, harmonic pollution, increased non-active power demand and potential voltage collapse. While most power system studies have focussed on the transformer's …
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Ensemble estimation and analysis of network parameters: strengthening the GIC modelling chain
… by solar activity and geomagnetic storms. Geomagnetically induced currents (GICs) in these quasiantennas are just one of the effects. In modern times, society has become more and more dependent on electrical power and, as a result, power networks. These power networks form extensive …
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Measurements and finite element modelling of transformer flux with dc and power frequency current
Geomagnetically induced currents (GIC’s) caused by solar storms or other sources of dc excitation in the presence of ac energization can disturb the normal operation of power transformers. If large enough, they cause half-cycle saturation of a power transformer’s core which could lead to …
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Impact of MHD-E3 on power system equipment and loads.
… field that is capable of inducing quasi-direct currents in long conductors such as electric transmission lines. These quasi-direct currents, on the order of 1000 amps within the power grid, will cause transformer saturation that leads to abnormal power absorption and high levels of harmonics in …
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