Alireza Majzoobi - Academia.edu (original) (raw)
Address: Norfolk, Virginia, United States
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Papers by Alireza Majzoobi
The evaluation of the power system overvoltages is necessary for the selection of dielectric stre... more The evaluation of the power system overvoltages is necessary for the selection of dielectric strength of power equipments. Lightning overvoltage is one of the major sources of equipment failure in transmission lines up to 400KV. Since the backflashover is the main part of lightning performance of high voltage transmission lines with presence of shield wires, this study has focused on Backflashover study in 230KV Double Circuit Transmission Line. In this paper, Backflashover has been studied with application of Monte Carlo method by using accurate models of transmission line, tower, grounding system and physical model of breakdown in insulator gap, in Arvandkenar-Abadan 132KV Double Circuit Transmission Line as a case study.
Techniques of line compaction have been developed with the aims of reducing the environmental imp... more Techniques of line compaction have been developed with the aims of reducing the environmental impacts of transmission lines and increasing voltage level of existing ones. Because of major differences between compact and conventional transmission lines, the previous lightning performance studies on conventional transmission lines are useless in this emerging environment and these studies should be updated and differences must be considered. The calculation of the lightning performance must take into account the random nature of lightning and the random behavior of some line parameters like phase angle of power frequency voltage in every phase at the lightning stroke instance. Application of Monte Carlo method can handle uncertainties introduced by random nature of these parameters and can help to make useful predictions to estimate lightning performance of a transmission line. In this paper, the differences between compact and conventional lines are considered in the line model and line lightning performance has been studied by application of Monte Carlo method for several scenarios introduced in literature. Moment method is used to determine tower surge impedance by SuperNEC software and an approximate model has been introduced for tower modeling in EMTP-RV
There are different methods for decreasing the outage rate due to lightning such as tower footing... more There are different methods for decreasing the outage rate due to lightning such as tower footing resistance reduction, increase of line insulation level, installation of additional ground and guy wires, addition of under-built ground wires, etc. limited effect or being expensive or difficult to use, are some of the reasons that make some of them impractical. But Line arresters are considered as an effective way to improve the lightning performance of transmission lines, especially in parts of line that suffer from high soil resistivity and lightning ground flash density. This paper presents results of the
application of line surge arresters on the 132KV double circuit transmission line in EMTP-RV and all the practical scenarios for installation of surge arresters have been studied and compared.
The evaluation of the power system overvoltages is necessary for the selection of dielectric stre... more The evaluation of the power system overvoltages is necessary for the selection of dielectric strength of power equipments. Lightning overvoltage is one of the major sources of equipment failure in transmission lines up to 400KV. Since the backflashover is the main part of lightning performance of high voltage transmission lines with presence of shield wires, this study has focused on Backflashover study in 230KV Double Circuit Transmission Line. In this paper, Backflashover has been studied with application of Monte Carlo method by using accurate models of transmission line, tower, grounding system and physical model of breakdown in insulator gap, in Arvandkenar-Abadan 132KV Double Circuit Transmission Line as a case study.
Techniques of line compaction have been developed with the aims of reducing the environmental imp... more Techniques of line compaction have been developed with the aims of reducing the environmental impacts of transmission lines and increasing voltage level of existing ones. Because of major differences between compact and conventional transmission lines, the previous lightning performance studies on conventional transmission lines are useless in this emerging environment and these studies should be updated and differences must be considered. The calculation of the lightning performance must take into account the random nature of lightning and the random behavior of some line parameters like phase angle of power frequency voltage in every phase at the lightning stroke instance. Application of Monte Carlo method can handle uncertainties introduced by random nature of these parameters and can help to make useful predictions to estimate lightning performance of a transmission line. In this paper, the differences between compact and conventional lines are considered in the line model and line lightning performance has been studied by application of Monte Carlo method for several scenarios introduced in literature. Moment method is used to determine tower surge impedance by SuperNEC software and an approximate model has been introduced for tower modeling in EMTP-RV
There are different methods for decreasing the outage rate due to lightning such as tower footing... more There are different methods for decreasing the outage rate due to lightning such as tower footing resistance reduction, increase of line insulation level, installation of additional ground and guy wires, addition of under-built ground wires, etc. limited effect or being expensive or difficult to use, are some of the reasons that make some of them impractical. But Line arresters are considered as an effective way to improve the lightning performance of transmission lines, especially in parts of line that suffer from high soil resistivity and lightning ground flash density. This paper presents results of the
application of line surge arresters on the 132KV double circuit transmission line in EMTP-RV and all the practical scenarios for installation of surge arresters have been studied and compared.