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Statistical approach for evaluation of current transformer saturation
2018 Simposio Brasileiro de Sistemas Eletricos (SBSE), 2018Historically, power system protection schemes were performed by electromechanical relays and regime symmetrical component currents. Many modern digital relays have been installed in the last years, replacing old electromechanical solutions, but not accompanied by the current transformers (CT) substitution due to their long life span.
Eduardo Bortolin Argenton +2 more
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Experimental evaluation of current transformer performance under saturation
2005 International Power Engineering Conference, 2005Current transformers form an integral part of protective systems. Ideal current transformers (CTs) are expected to reproduce the primary current faithfully on the secondary side. Often, during fault conditions an important component of current is exponentially decaying DC offset current.
CHAWANDE, PRADEEP +3 more
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Current related relaying algorithms immune to saturation of current transformers
6th International Conference on Developments in Power Systems Protection, 1997Current transformers (CTs) supplying protective relays may suffer permanent or transient saturation under severe faults. The majority of protective relays are more or less sensitive to CT saturation. On the other hand, contemporary microprocessor-based relays open the window of opportunity for performing sophisticated checking in order to either ...
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Detection of Partial Saturation and Waveform Compensation of Current Transformers
IEEE Transactions on Power Delivery, 2015Derivative-based approaches have been widely used for detecting current-transformer (CT) saturation. This letter proposes an efficient approach for detecting CT saturation with a generic discrimination index without the need for setting definition. For this aim, the simultaneous samples-based multiplication of the secondary current by its derivative is
Esmail, E. +5 more
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Current Transformer Saturation Compensator by Using Negative Voltage Feedback
IEEE Transactions on Power Delivery, 2020Current Transformers (CTs) saturation leads to distortion of current waveform and operational malfunction of protection relays. This paper introduces a practical and simple method to prevent CTs saturation. The method uses a negative voltage feedback and applies it to CT secondary side.
Mehdi Delzendeh, Hossein Kazemi Karegar
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Line current differential relay operation under severe current transformer saturation conditions
2009 62nd Annual Conference for Protective Relay Engineers, 2009Relays rely on the current transformer to produce a secondary current that faithfully reflects the primary current for proper operation. In some instances this isn't the case. This paper will look at cases where severe ct saturation can be a problem, review the real time digital simulator inputs to the relay, and look at what mechanisms in modern line ...
Roger A. Hedding, Stig Holst
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A current sourced inverter with saturating output transformer
1981 IEEE Power Electronics Specialists Conference, 1981A current sourced inverter with saturating output transformer offers advantages where a DC converter must regulate an isolated output voltage over a 10 to 1 range of input voltage in a dense package capable of 300 watt output.
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Current transformer saturation segmentation using morphological gradient-based detectors
2015 IEEE Innovative Smart Grid Technologies - Asia (ISGT ASIA), 2015This paper presents a novel algorithm for secondary current signal segmentation of saturated current transformer (CT) using three morphological gradient-based detectors. The saturation onset detector is used to monitor the occurrence of saturation and then trigger the positive/negative segmentation detector, which are designed to locate the starting ...
L. L. Zhang +3 more
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An Efficient Compensation Algorithm for Current Transformer Saturation Effects
IEEE Transactions on Power Delivery, 2004Current transformer (CT) saturation leads to inaccurate current measurement and, therefore, may cause malfunction of protective relays and control devices that use currents as input signals. This paper introduces an efficient compensation algorithm capable of converting from a sampled current waveform that is distorted by CT saturation to a compensated
J. Pan, K. Vu, Y. Hu
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Empirical analysis on transient saturation characteristic of current transformer
2017 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific), 2017Aiming at the problem of transient saturation of P class current transformer (TA) in power system, this paper simulates the working condition of TA in 330/110kV short circuit system. The transient saturation characteristics of TA are discussed and demonstrated in the form of exploratory test at transient currents up to 48kA.
Duan Jian-Dong +5 more
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