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Showing 1 to 18 of 18 for “"distance protection"”.
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Adaptive digital distance protection for series compensated transmission lines
… technical and economical advantages in long distance a. c. transmission. In particular, their excellent reliability and minimal maintenance requirements make series compensation the most cost effective method of enhancing the power transfer capability of an existing or proposed …
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Effect of STATCOM Location on Distance Protection Relay Operation
… has brought up some difficulties to conventional distance protection to meet basic requirements for protection schemes. This dissertation reviews FACTS concepts, and studies shunt-connected STATCOM and its modelling. Based on the dynamic behaviour of STATCOM in a two-machine system, where a …
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Distance Protection Aspects of Transmission Lines Equipped with Series Compensation Capacitors
… and better voltage regulation.1 Protective distance relays, which make use of impedance measurements in order to determine the presence and location of faults, are "fooled" by installed series capacitance on the line when the presence or absence of the capacitor in the fault circuit is not …
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An investigation into the importance of considering protection performance during power system out-of-step conditions
The performance of power system protection is affected by out-of-step conditions in that system. Protection relays such as distance relays may detect an out-of-step condition and consequently operate to trip unfaulted lines. The tripping of unfaulted lines interrupts supply to loads and exacerbates …
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One-terminal traveling wave-based protection for HVAC and HVDC transmission lines
… traveling wave-based transmission line protection methods for HVAC (High Voltage Alternating Current) and HVDC (High Voltage Direct Current) systems. It considers the effect of the sampling frequency on the protection, which until now has not been investigated for one-terminal methods. …
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Software framework for protection relay testing
… comprehensive automated testing of power system protection relays. This application was implemented using a model protection system that was designed to simulate actual relaying operations performed in the electric power system. The implemented application provided automated testing functionality …
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Recommended protection scheme setting coordination for nine busbars transmission grid
Protection system is one of the important parts of the power system. The protection system can be accepted if and only if it is efficient, reliable and realizes some requirements. For protection of transmission line three stepped distance protection can provide remote backup protection to …
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A novel backup protection scheme for hybrid AC/DC power systems
… via simulation and hardware-based tests) a new protection scheme designed to safeguard hybrid AC/DC distribution networks against DC faults that are not cleared by the main MVDC (Medium Voltage DC) link protection. The protection scheme relies on the apparent impedance measured at the AC "side" …
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Effects of GIC Neutral Blocking Devices (NBDs) on transmission lines protection performance and potential for resonance
… have arisen about the effects of NBDs on distance-protection relays. To investigate their impact, real-time simulation (of IEEE-39 bus system) with actual hardware-in-the-loop testing is utilized. The study showed that these relays are not affected by the insertion of NBDs regardless of …
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Design and implementation of POTT protection scheme using IEC-61850
… IEC 61850 describe rules for integration of protection, control, measurement and monitoring functions within a power system network at the process and station control levels. Earlier envisioned for substation automation, IEC 61850 has shown its potential in eliminating substation wiring, …
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Wide Area Measurement Applications for Improvement of Power System Protection
… that occur when the system is under stress, the protection systems are susceptible to mis-operation. It is under such severe situations that the network cannot afford to lose its critical elements like the main generation units and transmission corridors. In addition to the slow but steady …
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ACCELERATED ZONE-2 TRIP ALGORITHM FOR A NON-PILOT DISTANCE RELAY
Distance relays use time stepped protection zones for coordination purposes. The time delay introduced by zone-2 distance relays limits the use of these devices for extra high voltage (EHV) applications since the fast fault clearance requirement is not achieved. Transmission lines are normally …
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Design and implementation of ANN based phase comparators applied to transmission line protection
… in the area of neural network based power system protection in the previous decade. Neural network technology has been applied for various protective relaying functions including distance protection. The reliability and efficiency of ANN based distance relays is improving with the developing …
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Data-driven Protection of Transformers, Phase Angle Regulators, and Transmission Lines in Interconnected Power Systems
… employed to protect transformers, whereas distance relays are utilized to protect transmission lines. Magnetizing inrush, overexcitation, and current transformer saturation make transformer protection a challenge. Furthermore, non-standard phase shift, series core saturation, low …
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Design of a Distance Relay Using Adaptive Data Window Filters
Transmission lines are generally protected by distance relays. Most distance protection relays presently available use microprocessor technology. They estimate fundamental frequency phasors from the quantized values of voltage and current samples. The relays use filters that use fixed sample data …
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Low frequency ac transmission for power systems
… cost for converter stations and specialized protection systems. Additionally, the HVDC system is a point-to-point connection, and thus not flexible for multi-terminal connection. The low frequency ac (LFAC) transmission system, first introduced in 2000, is another solution for bulk power …
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Analysis of a Major Electric Grid – Stability and Adaptive Protection
… of faults and other disturbances that may occur. Distance relays are used extensively for the detection of faults on transmission lines. Out-of-step relays are used for generator protection to detect loss of synchronism conditions that result from disturbances on the electric grid. Also, when a …
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Switch-on-to-fault scheme for transmission line protection
… overreaching directional and nondirectional protection elements for a short window of time shortly after the transmission line breaker closes. When line potential transformers (PTs) are used to polarize directional distance relays, there is no benefit to using memory voltage during an SOTF …