Results 221 to 230 of about 7,748 (269)

Modeling overcurrent relay characteristics

IEEE Computer Applications in Power, 1992
An approach to computer modeling of the time-current characteristics of protective devices that relies on interactive manipulation and fitting of the curves, which are modeled mathematically as splines is presented. The approach is much easier to use than the commonly used curve-fitting methods, which are reviewed, and it does not require a digitizer ...
S. Chan, R. Maurer
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An Improved Static Overcurrent Relay

IEEE Transactions on Power Apparatus and Systems, 1963
This paper describes the design and application of a new static overcurrent protective relay system. Design goals and physical characteristics are given. Basis for selection of the new time current characteristics is presented, and new curves are compared with existing shapes. Also given are application examples involving fuse coordination, low-voltage
D. Dalasta, F. Free, A. De Snoo
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The effects of harmonics on overcurrent relays

2016 17th International Scientific Conference on Electric Power Engineering (EPE), 2016
This paper analyses the influence of current harmonics on protections devices connected to the power system which can cause serious problems. This paper outlines work that has been conducted to test of overcurrent relay and to identify the impacts of harmonics on distribution utility protection and control systems.
Kinan Wannous, Petr Toman
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Microprocessor-Based Overcurrent Relays

IEEE Transactions on Industrial Electronics, 1986
Inverse overcurrent is normally associated with the overcurrent relay types, the operation time is inversely proportional (in certain degrees) with their overcurrent ratio.
Mudhafar A. Al-Nema, Sinan M. Bashi, Abdulhadi A. Ubaid   +2 more
openaire   +1 more source

Effect of relay characteristics in optimum coordination of overcurrent relays

2020 IEEE Students Conference on Engineering & Systems (SCES), 2020
The coordination of overcurrent relays require minimum tripping time at maximum fault current while backup relays, experiencing low fault current, follow the coordination criteria. The challenges arise as overcurrent characteristics perform diversely according to the magnitude of fault currents.
Tejas M Vala, Vipul N Rajput, Kevin Joshi, Dipayan Guha   +3 more
openaire   +1 more source

Instantaneous Overcurrent Relays for Distance Relaying

Transactions of the American Institute of Electrical Engineers, 1935
Instantaneous isolation of faults on transmission and distribution lines is ever a problem of the relay engineer. The use of instantaneous overcurrent relays as applied to the system of the Oklahoma Gas and Electric Company is discussed in this paper. Relays of this type were applied in conjunction with already installed overcurrent time delay relays ...
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Correlation functions based directional overcurrent relay

2012 25th IEEE Canadian Conference on Electrical and Computer Engineering (CCECE), 2012
This paper describes a new directional overcurrent relay for protection of interconnected distribution network and DG unit. When the relay current exceeds its pick-up value, correlation of the voltage and current at the relay point as well as partial autocorrelation of the current are calculated.
Ebrahim Farjah, Teymoor Ghanbari, Saeed Rezaee   +2 more
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Operation Logic Proposed for Time Overcurrent Relays

IEEE Transactions on Power Delivery, 2006
This paper presents a new logic of operation for time overcurrent relays. With the application of the proposed technique, the sensitivity of time overcurrent relays is increased. In order to obtain this, the relay operates with a dynamic pickup setting, such as load current. Additionally, fast operation of overcurrent relays is obtained. The functional
A. Conde, E. Vazquez
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Optimal Combined Overcurrent and Distance Relays Coordination Incorporating Intelligent Overcurrent Relays Characteristic Selection

IEEE Transactions on Power Delivery, 2011
In this paper, a new objective function (OF) within the genetic algorithm (GA) approach is presented to solve the optimization problem of coordination of overcurrent and distance relays. The existing objective function of overcurrent (O/C) relays coordination is improved and extended to include the coordination of O/C and distance relays.
Reza Mohammadi Chabanloo, Hossein Askarian Abyaneh, Somayeh Sadat Hashemi Kamangar, Farzad Razavi   +3 more
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Design and Implementation of Overcurrent Protection Relay

Journal of Electrical Engineering & Technology, 2020
Protective relays have been designed with different technologies resulting in electromechanical, solid-state, and numerical devices. Speed and reliability are the two most important characteristics of a protective relay. Other capabilities such as monitoring and recording are supposed to be of secondary priority. The new technology using combination of
Mohammed Y. Suliman, Mohammed Ghazal
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