The Experts below are selected from a list of 3639 Experts worldwide ranked by ideXlab platform
C A Platero - One of the best experts on this subject based on the ideXlab platform.
-
novel rotor ground fault detection algorithm for synchronous machines with static excitation based on third harmonic voltage phasor comparison
IEEE Transactions on Industrial Electronics, 2016Co-Authors: F R Blanquez, E Rebollo, C A Platero, F BlazquezAbstract:This paper presents a new algorithm for detecting ground faults in rotor windings. This location method is suitable for synchronous generators with static excitation, whose excitation field winding is fed by controlled rectifiers through an excitation transformer. This new algorithm is an improvement of an online ground-fault location method presented previously, in which the effect of the rotor capacitance has a high influence in the correct detection of the fault. The detection of the ground fault is performed by the supervision of the phase angle between two phasor voltages. The first one is the third-harmonic phasor voltage obtained from the measurement of the field voltage, which is used as a reference. The second one is the third-harmonic voltage phasor obtained by the measurement in a Grounding Resistance placed in the neutral of the excitation transformer. It allows not only detecting the ground fault along the field winding but also distinguishing the cases of ground fault in the rotor winding, from the cases of high influence of the rotor capacitance in healthy condition. This new algorithm has been tested with satisfactory results in a 106-MVA hydro generating unit.
-
influence of rotor capacitance in on line rotor ground fault location method for synchronous machines with static excitation
International Conference on Environment and Electrical Engineering, 2013Co-Authors: F R Blanquez, Maria Dolores Avia Aranda, E Rebollo, C A PlateroAbstract:This paper presents results about the influence of rotor capacitance in the on-line rotor ground fault location method for synchronous machines with static excitation. The location method is based on the measurement of the voltage in a Grounding Resistance, connected to the neutral of the excitation transformer. Due to the effect of the rotor capacitance to ground on large synchronous generators, it is observed that waveform of the neutral voltage is perturbed, and it causes an error in the fault location in case of defect in the DC side. Firstly, the influence of the fault Resistance value and the fault position is evaluated through computer simulations. Then, the impact of the rotor capacitance in the accuracy of the detection and location method is analyzed in case of ground fault, as well as in healthy operating condition.
-
new on line rotor ground fault location method for synchronous machines with static excitation
IEEE Transactions on Energy Conversion, 2011Co-Authors: C A Platero, F Blazquez, Pablo Frias, M PardoAbstract:This paper presents a novel on-line rotor ground fault location method for synchronous machines, which, combined with rotor ground fault protection, can detect and locate faults in the rotor. This method is suitable for synchronous machines with static excitation systems, whose excitation field winding is fed by rectifiers through an excitation transformer. The main contribution of this new technique is that it can locate the position of a ground fault in the rotor winding online, reducing the repair time. The proposed technique is based on the analysis of the ac and dc components of the excitation voltage and the voltage measured in a Grounding Resistance located in the neutral terminal of the excitation transformer. This technique has been validated through computer simulations and experimental laboratory tests.
F Blazquez - One of the best experts on this subject based on the ideXlab platform.
-
novel rotor ground fault detection algorithm for synchronous machines with static excitation based on third harmonic voltage phasor comparison
IEEE Transactions on Industrial Electronics, 2016Co-Authors: F R Blanquez, E Rebollo, C A Platero, F BlazquezAbstract:This paper presents a new algorithm for detecting ground faults in rotor windings. This location method is suitable for synchronous generators with static excitation, whose excitation field winding is fed by controlled rectifiers through an excitation transformer. This new algorithm is an improvement of an online ground-fault location method presented previously, in which the effect of the rotor capacitance has a high influence in the correct detection of the fault. The detection of the ground fault is performed by the supervision of the phase angle between two phasor voltages. The first one is the third-harmonic phasor voltage obtained from the measurement of the field voltage, which is used as a reference. The second one is the third-harmonic voltage phasor obtained by the measurement in a Grounding Resistance placed in the neutral of the excitation transformer. It allows not only detecting the ground fault along the field winding but also distinguishing the cases of ground fault in the rotor winding, from the cases of high influence of the rotor capacitance in healthy condition. This new algorithm has been tested with satisfactory results in a 106-MVA hydro generating unit.
-
new on line rotor ground fault location method for synchronous machines with static excitation
IEEE Transactions on Energy Conversion, 2011Co-Authors: C A Platero, F Blazquez, Pablo Frias, M PardoAbstract:This paper presents a novel on-line rotor ground fault location method for synchronous machines, which, combined with rotor ground fault protection, can detect and locate faults in the rotor. This method is suitable for synchronous machines with static excitation systems, whose excitation field winding is fed by rectifiers through an excitation transformer. The main contribution of this new technique is that it can locate the position of a ground fault in the rotor winding online, reducing the repair time. The proposed technique is based on the analysis of the ac and dc components of the excitation voltage and the voltage measured in a Grounding Resistance located in the neutral terminal of the excitation transformer. This technique has been validated through computer simulations and experimental laboratory tests.
M Pardo - One of the best experts on this subject based on the ideXlab platform.
-
new on line rotor ground fault location method for synchronous machines with static excitation
IEEE Transactions on Energy Conversion, 2011Co-Authors: C A Platero, F Blazquez, Pablo Frias, M PardoAbstract:This paper presents a novel on-line rotor ground fault location method for synchronous machines, which, combined with rotor ground fault protection, can detect and locate faults in the rotor. This method is suitable for synchronous machines with static excitation systems, whose excitation field winding is fed by rectifiers through an excitation transformer. The main contribution of this new technique is that it can locate the position of a ground fault in the rotor winding online, reducing the repair time. The proposed technique is based on the analysis of the ac and dc components of the excitation voltage and the voltage measured in a Grounding Resistance located in the neutral terminal of the excitation transformer. This technique has been validated through computer simulations and experimental laboratory tests.
F R Blanquez - One of the best experts on this subject based on the ideXlab platform.
-
novel rotor ground fault detection algorithm for synchronous machines with static excitation based on third harmonic voltage phasor comparison
IEEE Transactions on Industrial Electronics, 2016Co-Authors: F R Blanquez, E Rebollo, C A Platero, F BlazquezAbstract:This paper presents a new algorithm for detecting ground faults in rotor windings. This location method is suitable for synchronous generators with static excitation, whose excitation field winding is fed by controlled rectifiers through an excitation transformer. This new algorithm is an improvement of an online ground-fault location method presented previously, in which the effect of the rotor capacitance has a high influence in the correct detection of the fault. The detection of the ground fault is performed by the supervision of the phase angle between two phasor voltages. The first one is the third-harmonic phasor voltage obtained from the measurement of the field voltage, which is used as a reference. The second one is the third-harmonic voltage phasor obtained by the measurement in a Grounding Resistance placed in the neutral of the excitation transformer. It allows not only detecting the ground fault along the field winding but also distinguishing the cases of ground fault in the rotor winding, from the cases of high influence of the rotor capacitance in healthy condition. This new algorithm has been tested with satisfactory results in a 106-MVA hydro generating unit.
-
influence of rotor capacitance in on line rotor ground fault location method for synchronous machines with static excitation
International Conference on Environment and Electrical Engineering, 2013Co-Authors: F R Blanquez, Maria Dolores Avia Aranda, E Rebollo, C A PlateroAbstract:This paper presents results about the influence of rotor capacitance in the on-line rotor ground fault location method for synchronous machines with static excitation. The location method is based on the measurement of the voltage in a Grounding Resistance, connected to the neutral of the excitation transformer. Due to the effect of the rotor capacitance to ground on large synchronous generators, it is observed that waveform of the neutral voltage is perturbed, and it causes an error in the fault location in case of defect in the DC side. Firstly, the influence of the fault Resistance value and the fault position is evaluated through computer simulations. Then, the impact of the rotor capacitance in the accuracy of the detection and location method is analyzed in case of ground fault, as well as in healthy operating condition.
Tao Yuan - One of the best experts on this subject based on the ideXlab platform.
-
analysis of error correction for backward Grounding Resistance measurement method with short lead wire considering shunt phenomenon
IEEE International Conference on High Voltage Engineering and Application, 2020Co-Authors: Qingjun Peng, Fangrong Zhou, Tao YuanAbstract:In order to ensure the safe and stable operation of the substation, it is necessary to test and evaluate the substation Grounding grid. In the actual measurement process, since the overhead ground wire is difficult to disconnect from the ground network, in order to obtain accurate measurement results, it is necessary to consider the influence of the shunt phenomenon on the Grounding Resistance measurement of the Grounding network. In recent years, the Resistance measurement method with short lead wire has gained wide attention due to the advantages brought by its shorter measurement leads. Based on the backward measurement method with short lead wire, this paper considers the influence of the shunt coefficient on its measurement results, proposes a correction formula through theoretical derivation, and proposes an improved method of it, which is verified by simulation. The improved method proposed in this paper improves its accuracy while preserving advantages of the original method, and it has certain significance for the measurement of large-scale Grounding grids.
-
preparation of steel fiber graphite conductive concrete for Grounding in substation
International Conference on High Voltage Engineering and Application, 2014Co-Authors: De Zhang, Xinzhu Yan, Tao YuanAbstract:In high soil resistivity regions, values of Grounding Resistance of substations are usually difficult to meet the requirements of working earthing and safety earthing. The common methods for reducing the Grounding Resistance are not practical. In order to solve this problem, a steel fiber/graphite conductive concrete is developed in this paper. Steel fiber and graphite are added as conductive fillers. Orthogonal experimental design is applied to formulation optimization. The resistivity, compressive strength and flexural strength of steel fiber/graphite conductive concrete are measured for obtaining the optimal formula. The results demonstrate that the steel fiber/graphite conductive concrete not only has the advantage of small resistivity, but also has excellent mechanical property and good material dispersion effect.
