The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Changhui Yang - One of the best experts on this subject based on the ideXlab platform.
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The electric energy loss in overhead Ground Wires of 110kV six-circuit transmission line on the same tower
IEEE PES Innovative Smart Grid Technologies, 2012Co-Authors: Hui Wang, Luyang Wang, Yufei Wang, Changhui YangAbstract:In order to provide theoretical guidance for reducing the electric energy loss of 110kV six-circuit transmission line on the same tower, the factors affecting electric energy loss in overhead Ground Wires are deeply studied. Firstly, the model of 110kV six-circuit transmission line on the same tower is established in MATLAB. Secondly, the effect of phase sequence arrangements on electric energy loss is studied. Finally, the effects on electric energy loss of varying relative position between two overhead Ground Wires, horizontal distance and vertical distance among transmission lines are studied. The results show that phase sequence arrangements have a great influence on power loss in overhead Ground Wire. The inverse phase sequence arrangement is validated to be optimized layout. The electric energy loss is positively correlated with horizontal distance between two overhead Ground Wires and negatively correlated with vertical distance from overhead Ground Wires to the Ground.
Yunqi Hao - One of the best experts on this subject based on the ideXlab platform.
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development of optical fiber sensors based on brillouin scattering and fbg for on line monitoring in overhead transmission lines
Journal of Lightwave Technology, 2013Co-Authors: Jianbin Luo, Yanpeng Hao, Yunqi HaoAbstract:A distributed on-line temperature and strain fiber sensing system based on the combined Brillouin optical time domain reflectometry (BOTDR) and fiber Bragg grating (FBG) technology is presented and investigated experimentally for monitoring the overhead transmission lines. The BOTDR sensing system can be used to measure the temperature of transmission lines (Optical Phase Conductor, OPPC or Optical Power Ground Wire, OPGW) which is helpful for monitoring the dynamic ampacity and icing forecasting. In order to effectively monitor the distortion of transmission line induced by the climatic fluctuation and natural disaster, e.g., ice coating and hurricane wind, a quasi-distributed FBG strain sensing system is connected in series with the insulator, integrated into the BOTDR system. The results showed the proposed system was effective and reliable for the monitoring of overhead transmission lines.
Yutaka Goda - One of the best experts on this subject based on the ideXlab platform.
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breaking characteristics of 60 mm 2 opgw strands due to dc arc simulating high energy lightning strike
International Conference on Lightning Protection, 2018Co-Authors: Mikimasa Iwata, Toshiya Ohtaka, Masashi Kotari, Yutaka GodaAbstract:Metal strands of composite fiber-optic Ground Wire (OPGW) are sometimes melted and broken by highenergy lightning strikes. Direct current (DC) arc tests simulating lightning strikes have thus been performed to obtain the melting and breaking characteristics of OPGW strands. In this paper, DC arc tests were conducted on the melting and breaking of 60 mm2 OPGW for different currents and electric charges to clarify the characteristics of thin OPGWs. The results show that the number of broken strands increased as arc current decreased when comparing at the same electric charge, although it was previously reported that the melting quantity of the metal electrode due to arc discharges was proportional to electric charge without depending on the arc current. Furthermore, the characteristics of the tensile strength of the OPGW after DC arc tests were clarified.
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calculation of melting breaking of gw and opgw strands struck by dc arc discharge simulating high energy lightning
Electric Power Systems Research, 2014Co-Authors: Mikimasa Iwata, Toshiya Ohtaka, Yutaka GodaAbstract:Abstract Some metal strands of Ground Wire (GW) and composite fiber-optic Ground Wire (OPGW) are sometimes melted and broken by high energy lightning strikes. Direct current (DC) arc tests simulating high energy lightning strikes have thus been performed to obtain the melting and breaking characteristics of these strands. In this work, calculations regarding these characteristics are performed considering the transferred heat and its area from the arc to the strands. The melting/breaking characteristics of the strands are calculated for arc currents of 0.1–100 kA, considering the current prescribed in the IEC standard and the measured actual lightning current. The calculation results of the strand-breaking duration depending on the arc current show good agreement with the experimental values obtained in DC arc tests. Furthermore, the calculation results show that the IEC standard testing conditions are far more severe than those in the cases of a higher current and longer gap.
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development of a method of calculating the melting characteristics of opgw strands due to dc arc simulating lightning strike
IEEE Transactions on Power Delivery, 2013Co-Authors: Mikimasa Iwata, Toshiya Ohtaka, Y Kuzuma, Yutaka GodaAbstract:Some strands of composite fiber-optic Ground Wire (OPGW) are sometimes melted and broken by high-energy lightning strikes. DC arc tests simulating lightning strikes have been performed to obtain the melting and breaking characteristics of OPGW strands. The tests have to be performed under many conditions concerning the arc (e.g., current, duration, polarity, gap length) and the OPGW (e.g., size, type, and number of strands) to clarify the melting and breaking characteristics of the strands. In this paper, the calculations regarding the melting characteristics of strands are performed considering the transferred heat and its area from the arc to the strands under the aforementioned conditions. The melting characteristics of strands are calculated with an arc current of 1-100 kA considering the measured current of actual lightning. The calculation results of the strand melting duration depending on arc current show good agreement with the experimental values obtained in dc arc tests.
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melting and breaking characteristics of opgw strands by lightning
IEEE Transactions on Power Delivery, 2004Co-Authors: Yutaka Goda, S Yokoyama, S Watanabe, T Kawano, S KandaAbstract:Some strands were melted and broken in a 140 mm/sup 2/ OPGW (composite fiber-optic Ground Wire) in a 187 kV transmission line. It was assumed that this was caused by a lightning strike. DC arc tests simulating lightning strikes were carried out, and the melting and breaking characteristics of OPGW strands were obtained. The electric charge of the lightning strike that damaged the OPGW was estimated from the number of strands broken by the DC arc. In this paper, the DC arc test results, and the test conditions required to simulate a powerful lightning strike are described.
Hui Wang - One of the best experts on this subject based on the ideXlab platform.
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The electric energy loss in overhead Ground Wires of 110kV six-circuit transmission line on the same tower
IEEE PES Innovative Smart Grid Technologies, 2012Co-Authors: Hui Wang, Luyang Wang, Yufei Wang, Changhui YangAbstract:In order to provide theoretical guidance for reducing the electric energy loss of 110kV six-circuit transmission line on the same tower, the factors affecting electric energy loss in overhead Ground Wires are deeply studied. Firstly, the model of 110kV six-circuit transmission line on the same tower is established in MATLAB. Secondly, the effect of phase sequence arrangements on electric energy loss is studied. Finally, the effects on electric energy loss of varying relative position between two overhead Ground Wires, horizontal distance and vertical distance among transmission lines are studied. The results show that phase sequence arrangements have a great influence on power loss in overhead Ground Wire. The inverse phase sequence arrangement is validated to be optimized layout. The electric energy loss is positively correlated with horizontal distance between two overhead Ground Wires and negatively correlated with vertical distance from overhead Ground Wires to the Ground.
Jianbin Luo - One of the best experts on this subject based on the ideXlab platform.
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development of optical fiber sensors based on brillouin scattering and fbg for on line monitoring in overhead transmission lines
Journal of Lightwave Technology, 2013Co-Authors: Jianbin Luo, Yanpeng Hao, Yunqi HaoAbstract:A distributed on-line temperature and strain fiber sensing system based on the combined Brillouin optical time domain reflectometry (BOTDR) and fiber Bragg grating (FBG) technology is presented and investigated experimentally for monitoring the overhead transmission lines. The BOTDR sensing system can be used to measure the temperature of transmission lines (Optical Phase Conductor, OPPC or Optical Power Ground Wire, OPGW) which is helpful for monitoring the dynamic ampacity and icing forecasting. In order to effectively monitor the distortion of transmission line induced by the climatic fluctuation and natural disaster, e.g., ice coating and hurricane wind, a quasi-distributed FBG strain sensing system is connected in series with the insulator, integrated into the BOTDR system. The results showed the proposed system was effective and reliable for the monitoring of overhead transmission lines.
