In order to improve the reliability of the power system and provide uninterrupted power to the consumer, automatic reclosing (ARC) devices are often used in overhead power lines. On top of that, the condition of short...In order to improve the reliability of the power system and provide uninterrupted power to the consumer, automatic reclosing (ARC) devices are often used in overhead power lines. On top of that, the condition of short-circuit elimination or removal during ARC recloser depends on many random factors. In this article, the number of outages of 110 kV overhead lines in the Khangai region of Mongolia was studied, and the statistics of ARC device operation were compared with international standards. Also, from the works produced by scientists from foreign countries, the development level and innovative trends of ARC devices were compared and studied, and the opportunity to introduce them to Mongolia’s grid system was sought. Furthermore, the 110 kV transmission lines outage and the operation of the ARC devices installed in the Khangai region of Mongolia were studied. Hence, the average operation success rate of the ARC device in the last ten years was 76%. It was also found that the number of outages of 110 kV power lines is 8 per year on average, which is 2 - 3 times higher than the international norm. Eventually, the power grid scheme of the Khangai region, especially the Bulgan-Murun 110 kV distribution network, was modelled by Digsilent Powerfactory by including the features of Mongolia’s power transmission network, and the operation of the model was checked by the load flow function of the software.展开更多
Usually,rural areas can be electrified via three-phase distribution transformers with relatively large capacities.In such areas,low voltage lines are used for long distances,which cause power losses and voltage drop f...Usually,rural areas can be electrified via three-phase distribution transformers with relatively large capacities.In such areas,low voltage lines are used for long distances,which cause power losses and voltage drop for different types of consumers.Reducing losses and improving voltage profiles in rural distribution networks are significant challenges for electricity distribution companies.However different solutions were proposed in the literature to overcome these challenges,most of them face difficulties when applied in the conventional distribution network.To address the above issues,an applicable solution is proposed in this paper by installing a number of small-capacity distribution transformers instead of every single large-capacity transformer in rural areas.The proposed approach is implemented in the branch network of Al-Hoqool village,which belongs to the Nineveh distribution network.The network has been inspected on-site,drawn,and analyzed using the electrical systems analysis program(ETAP).The analysis showed that using the single-phase pole-mounted transformers can improve the voltage in the network’s end by 29%and enhance the voltage profile for all consumers.The analysis has also demonstrated that the modification can reduce the total power losses by 78%compared to the existing network.Concerning the economic aspect,the payback period for the proposed network is assigned to be 20 months.展开更多
Two forms of basic equations and 5 basic matrices in the matrix analysis of networks from nonlinear networks to linear networks are obtained and their origins in physics are correctly explained. Furthermore, the whole...Two forms of basic equations and 5 basic matrices in the matrix analysis of networks from nonlinear networks to linear networks are obtained and their origins in physics are correctly explained. Furthermore, the whole 12 general characteristic formulae of the 4 fundamental network elements as well as some important new results, which were not in the conventional theory, have also been obtained during inference for both nonlinear and linear networks.展开更多
A field theory has been proposed. The laws of conservation of charge and energy can be obtained from the Maxwell’s equations, which are placed in nonlinear network for simultaneous solution, and therefore the Kirchh...A field theory has been proposed. The laws of conservation of charge and energy can be obtained from the Maxwell’s equations, which are placed in nonlinear network for simultaneous solution, and therefore the Kirchhoff’s law with its most fundamental integral formulae in nonlinear network can be obtained. Thus, it will strictly push forward the total basic equations from non-linear network to linear network as well as other important new relationships to provide the theoretical grounds for the field theory.展开更多
文摘In order to improve the reliability of the power system and provide uninterrupted power to the consumer, automatic reclosing (ARC) devices are often used in overhead power lines. On top of that, the condition of short-circuit elimination or removal during ARC recloser depends on many random factors. In this article, the number of outages of 110 kV overhead lines in the Khangai region of Mongolia was studied, and the statistics of ARC device operation were compared with international standards. Also, from the works produced by scientists from foreign countries, the development level and innovative trends of ARC devices were compared and studied, and the opportunity to introduce them to Mongolia’s grid system was sought. Furthermore, the 110 kV transmission lines outage and the operation of the ARC devices installed in the Khangai region of Mongolia were studied. Hence, the average operation success rate of the ARC device in the last ten years was 76%. It was also found that the number of outages of 110 kV power lines is 8 per year on average, which is 2 - 3 times higher than the international norm. Eventually, the power grid scheme of the Khangai region, especially the Bulgan-Murun 110 kV distribution network, was modelled by Digsilent Powerfactory by including the features of Mongolia’s power transmission network, and the operation of the model was checked by the load flow function of the software.
文摘Usually,rural areas can be electrified via three-phase distribution transformers with relatively large capacities.In such areas,low voltage lines are used for long distances,which cause power losses and voltage drop for different types of consumers.Reducing losses and improving voltage profiles in rural distribution networks are significant challenges for electricity distribution companies.However different solutions were proposed in the literature to overcome these challenges,most of them face difficulties when applied in the conventional distribution network.To address the above issues,an applicable solution is proposed in this paper by installing a number of small-capacity distribution transformers instead of every single large-capacity transformer in rural areas.The proposed approach is implemented in the branch network of Al-Hoqool village,which belongs to the Nineveh distribution network.The network has been inspected on-site,drawn,and analyzed using the electrical systems analysis program(ETAP).The analysis showed that using the single-phase pole-mounted transformers can improve the voltage in the network’s end by 29%and enhance the voltage profile for all consumers.The analysis has also demonstrated that the modification can reduce the total power losses by 78%compared to the existing network.Concerning the economic aspect,the payback period for the proposed network is assigned to be 20 months.
文摘Two forms of basic equations and 5 basic matrices in the matrix analysis of networks from nonlinear networks to linear networks are obtained and their origins in physics are correctly explained. Furthermore, the whole 12 general characteristic formulae of the 4 fundamental network elements as well as some important new results, which were not in the conventional theory, have also been obtained during inference for both nonlinear and linear networks.
文摘A field theory has been proposed. The laws of conservation of charge and energy can be obtained from the Maxwell’s equations, which are placed in nonlinear network for simultaneous solution, and therefore the Kirchhoff’s law with its most fundamental integral formulae in nonlinear network can be obtained. Thus, it will strictly push forward the total basic equations from non-linear network to linear network as well as other important new relationships to provide the theoretical grounds for the field theory.
