Results 241 to 250 of about 114,627 (294)

Detection of Saturation and Reconstruction of the Secondary Current of a CT

International Journal of Emerging Electric Power Systems, 2010
During a short circuit condition, core of a Current Transformer (CT) may become saturated due to large primary current containing a significant DC component. The saturation of the core distorts the secondary current which may cause malfunction of the protective devices connected to the CT.
Ganesh Balu Kumbhar, Satish M Mahajan
openaire   +1 more source

Compensation of the distortion in the secondary current caused by saturation and remanence in a CT

IEEE Power Engineering Society General Meeting, 2004., 2004
Current-transformer (CT) saturation may cause the maloperation of a protection relay. This is particularly onerous when the remanent flux in the core of the CT adds to the flux change caused by the fault. The CT is forced into deep saturation and the waveshape of the secondary current is severely distorted.
Y.C. Kang, U.J. Lim, S.H. Kang, P.A. Crossley   +3 more
openaire   +1 more source

CT saturation effects on performance of digital overcurrent relays

2011 International Conference on Advanced Power System Automation and Protection, 2011
In general, modeling the behavior of the core in current transformers (CTs) used for protection and the effects of its operation outside the linear region are commonly reported in literature. The problem in using a mathematical TC model is to obtain the parameters in a particular case in order to implement that model easily, efficiently and accurately.
Aurelio Luiz Magalhaes Coelho, Paulo Marcio Silveira   +1 more
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The impact of the CT saturation on the HVDC protection and its countermeasure

IEEJ Transactions on Electrical and Electronic Engineering, 2017
Converter protection, including bridge differential protection and valve short‐circuit protection, frequently malfunctions during the disturbance from an AC system, such as the short‐circuit fault and the inrush current, which severely threatens the safe and stable operation of an AC/DC hybrid power system.
Wenbin Cao, Xuanwei Qi, Kanjun Zhang, Xianggen Yin, Zhe Zhang, Qian Guo   +5 more
openaire   +1 more source

A discrete dynamic filter for detecting and compensating CT saturation

Electric Power Systems Research, 2007
Current transformers (CTs) are used in electric power systems for protection and measurement purposes. The current signals in the secondary side of a CT should be exact reproductions of the corresponding current signals on its primary side. CTs are susceptible to the saturation phenomenon which leads to inaccurate current measurement and therefore, may
K.M. El-Naggar, M.I. Gilany
openaire   +1 more source

A CT Saturation Detection Algorithm Based on Wavelet Transformation

12th IET International Conference on Developments in Power System Protection (DPSP 2014), 2014
Current Transformer (CT) saturation may cause the maloperation or operating time delay of protective relays. In this paper, a CT saturation detection algorithm based on wavelet transformation is suggested. The WT (Wavelet Transformation) can be easily implemented with the multilevel filter banks.
null Sang-Hee Kang, null Min-Soo Kim, J.H. Shin, null Soon-Ryul Nam, null Jong-Jin Jung   +4 more
openaire   +1 more source

Optical current sensors eliminate CT saturation

2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309), 2003
Optical current sensors are achieving increased acceptance and use in high voltage substations due to their superior accuracy, bandwidth, dynamic range and inherent isolation. Once deemed specialized devices intended for novel applications, optical sensors have risen to a performance level exceeding conventional magnetic devices.
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New Method to Identify CT Saturation Based on EMD

Advanced Materials Research, 2013
Aiming at the problem that Current Transformer (CT) affects differential protection, this paper proposes a new method to identify CT saturation based on Empirical Mode Decomposition (EMD). Differential current can be decomposed into few Intrinsic Mode Functions (IMFs) by EMD.
Wen Hua Xia, Mao Fa Gong, Guo Liang Li, Jian Yu Zhang, Xin Cheng   +4 more
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Phasor Estimation in the Presence of DC Offset and CT Saturation

IEEE Transactions on Power Delivery, 2009
A hybrid algorithm for phasor estimation is proposed that is immune to DC offset and current transformer (CT) saturation problems. The algorithm utilizes partial sum (PS)-based and multistage least-squares (MLS)-based methods before and after CT saturation is detected, respectively.
Soon-Ryul Nam, Jong-Young Park, Sang-Hee Kang, Mladen Kezunovic   +3 more
openaire   +1 more source

Beyond the knee point: A practical guide to CT saturation

2018 71st Annual Conference for Protective Relay Engineers (CPRE), 2018
Current transformer (CT) saturation, while a fairly common occurrence in protection systems, is not often clearly understood by protective relay engineers. This paper forgoes the usual physics equations to describe how CTs saturate in a simple and intuitive way.
Ariana Hargrave, Michael J. Thompson, Brad Heilman   +2 more
openaire   +1 more source