scholarly journals Selection of a Complex of Parameters of Distribution Electric Networks with Respect to Technical Limitations

2020 ◽  
Vol 209 ◽  
pp. 07013
Author(s):  
A D Taslimov

The article contains an optimization analysis of the regularities of the formation of the parameters of urban distribution networks of 10 kV, taking into account the technical limitations by the method of criteria analysis, which revealed the feasibility of using a limited number of used cable cross-sections, depending on the density of the electrical load and on the schemes of urban distribution networks.

Computation ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 80
Author(s):  
John Fernando Martínez-Gil ◽  
Nicolas Alejandro Moyano-García ◽  
Oscar Danilo Montoya ◽  
Jorge Alexander Alarcon-Villamil

In this study, a new methodology is proposed to perform optimal selection of conductors in three-phase distribution networks through a discrete version of the metaheuristic method of vortex search. To represent the problem, a single-objective mathematical model with a mixed-integer nonlinear programming (MINLP) structure is used. As an objective function, minimization of the investment costs in conductors together with the technical losses of the network for a study period of one year is considered. Additionally, the model will be implemented in balanced and unbalanced test systems and with variations in the connection of their loads, i.e., Δ− and Y−connections. To evaluate the costs of the energy losses, a classical backward/forward three-phase power-flow method is implemented. Two test systems used in the specialized literature were employed, which comprise 8 and 27 nodes with radial structures in medium voltage levels. All computational implementations were developed in the MATLAB programming environment, and all results were evaluated in DigSILENT software to verify the effectiveness and the proposed three-phase unbalanced power-flow method. Comparative analyses with classical and Chu & Beasley genetic algorithms, tabu search algorithm, and exact MINLP approaches demonstrate the efficiency of the proposed optimization approach regarding the final value of the objective function.


2017 ◽  
Vol 56 (5) ◽  
pp. 959-972 ◽  
Author(s):  
Christian Krogh ◽  
Mathias H. Jungersen ◽  
Erik Lund ◽  
Esben Lindgaard

2021 ◽  
Vol 3 (27) ◽  
pp. 101-115
Author(s):  
Massoud Danishmal ◽  

The design of power distribution systems should be such that it can technically respond to the increase in electricity demand properly and economically, optimally designed and high network reliability. In order to respond to the increase in electricity demand, load forecasting must be done so that in addition to providing the electricity needed by customers, expansion of power generation centers, expansion of substations, expansion of transformer stations and selection of their appropriate location can be done optimally. In this article, we first examine the definitions and factors that are technically and economically effective in the economic design of energy distribution systems. And in the next stage, we will see whether these above-mentioned effective factors are considered in the 0.4 kV distribution network of Ghazni city or not.


Author(s):  
Y. A. Sekretarev ◽  
D. A. Menyaikin

Reliability of power supply of consumers is an important task in the process of transmission and distribution of electric energy. The paper proposes a method for assessing the consequences of power failures of monoconsumers of electric energy on the example of an oil company and an adjacent power grid company. The uniqueness of the developed technique lies in the possibility of reliable calculation of reliability of power supply of complex branched electric networks without taking into account the specific scheme of power supply. The accuracy of calculations is increased due to the use of data directly studied power system, taking into account the specifics and operating conditions of specific equipment, instead of the average information. Classification of failures on the main reasons in electric networks of the oilproducing enterprise of the far North that allowed to develop actions for increase of level of reliability of power supply is made.


2019 ◽  
Vol 5 (4) ◽  
pp. 73-95
Author(s):  
Nikolai A. Senkin ◽  
Aleksandr S. Filimonov ◽  
Kirill E. Kharitonov ◽  
Vitaliy V. Yakovlev ◽  
Elizaveta O. Bondareva ◽  
...  

As part of student research at the St. Petersburg University of architecture and construction, alternative proposals are being developed for the creation of a circumferential high-speed highway with a total length of 147.2 km. Тhe scheme is proposed in the form of a polygon with HUB in the nodes and consists of three main parts: 1 above-ground (62.6 km), 2 above-water (29.6 km) and 3 surface-underground (55.0 km). The main tracks are located in a four-tube steel beam, each tube of which is organized by the technology of vacuum tube transport with a pressure of 10% of the normal for high-speed passenger trains on a magnetic levitation cushion using a linear traction motor (Maglev system). The rail base of the 1520 mm gauge is located along the entire length of the track, both in parking lots, acceleration and braking zones, and on the main high-speed sections for movement with a maximum speed of 500 km per hour. The main direction of research was the development of load-bearing structures that provide the necessary functionality, reliability and safety of structures. In order to reduce the noise impact on the metropolis, overcome numerous artificial and natural obstacles, improve anti-terrorist protection, the main level of the rail track for the above-ground and above-water structures was adopted at +88.00 in the Baltic elevation system. Calculations of variants with determination of internal forces in elements and movements of nodes with use of the program complex SCAD Office 21.1are executed, when accounting for the full range of loads taking into account dynamic effects and non-linearity. The selection of cross-sections of elements according to the method of limit states according to the current norms is carried out. The advantage of the arch-cable-stayed variant with a span of 360 m in strength, stability, stiffness and vertical size (height of supports) is shown. The continuation of research and design work on this topic should lead to the emergence of a district high-speed transport system at the borders of communication between St. Petersburg and the Leningrad region with passenger traffic, quite comparable to the metro line. Aim: To develop a district high-speed transport system at the borders of St. Petersburg and Leningrad region with passenger traffic comparable to the metro line. Materials and Methods: Using the software package "SCAD Office 21.1", the trestle structures are calculated for the combination of operating loads, forces and influences, including the consideration of dynamic aspects and nonlinearity, as well as the selection of cross-sections of elements by the method of limit states. To determine the optimal trestle structures of high-speed highways, namely high-rise and long-length metal structures supporting the overpass beam, calculations with the selection of cross sections of four variants of cable-stayed systems (arch-cable-stayed; cable-stayed rod with inclined cables and steel lattice pylons; the same, steel pipe-concrete pylons; cable-stayed rod system with suspensions according to the patent US5950543 (A). Results: the results of the trial design adopted arch-cable option with a span of 360 m according to the criterion of metal consumption, the consumption of steel amounted to 20.9 tons per 1 m length of highway. Conclusion: the estimated volume of passenger traffic per day for the four-track high-speed line will be 280 thousand passengers, and 102 million passengers per year, which is quite comparable to this figure for the metro line.


2021 ◽  
Vol 14 (3) ◽  
pp. 100-110
Author(s):  
I. V. Naumov

Analysis has been performed of the operation of electric distribution networks of ten branches of Oblkommunenergo (OKE) of Irkutsk Region [1]. Based on the data on the operation of these networks published in public media, algorithms and computer programs for the Matlab graphic editor are compiled, which are used for plotting time diagrams that characterize the operation of the electrical networks under consideration. The balance changes are shown in the transmission of electric energy into the OKE networks and from the OKE networks directly to consumers (high, medium and low voltage networks). The number of failures, the power supply interruption time and the amount of electricity undersupplied in each month of the year for each of the branches are considered. The months of the year are determined, in which the greatest and least damage occurs to the electrical networks of the OKE branches. Data are presented on the dynamics of annual wear of electric networks, planned activities and their annual implementation. The level of reliability is considered according to the established indicators of the average duration of interruptions in the transmission of electric energy in each calculated regulation period. It is shown that the combination of the main causes of failures largely depends on the natural-climatic and terrain specifics of the regions through which the routes of electric networks pass. As an example, data on the causes of failure in the electrical networks of one of the OKE branches are considered. The most and least damaged electrical networks of the considered OKE branches have been established. In conclusion, findings are formulated and recommendations are presented on minimizing outages based on the main types of failure causes for the purpose of increasing the operational reliability of the electrical networks under consideration.


Author(s):  
Ю.В. Брянская ◽  
А.Э. Тен ◽  
Н.Т. Джумагулова ◽  
Г.Н. Громов

В условиях интенсивного развития новых отечественных и зарубежных технологий, материалов и оборудования, применяемых для защиты окружающей природной среды от загрязнений техногенного происхождения, особую актуальность приобретают разработки новых систем отвода и очистки поверхностных сточных вод. Эти системы позволяют использовать последние достижения отраслевой науки и оптимизировать алгоритм выполнения операций и практических приемов их гидравлического расчета. Примером является инновационная система отвода поверхностных сточных вод АСО Qmax, которая относится к открытой системе каналов (лотков) для сбора и отведения поверхностных сточных вод, формирующихся при выпадении атмосферных осадков. Однако широкому применению данного вида конструкций в России препятствует отсутствие методики их гидравлического расчета, в том числе таблиц для подбора сечений (диаметров) каналов, которая бы удовлетворяла требованиям российской нормативно-методической базы проектирования систем отведения поверхностных сточных вод. В этой связи предметом данной статьи явилась оценка гидравлических характеристик трубопроводов, каналов (лотков) системы водоотвода АСО Qmax. Приведены результаты теоретических и экспериментальных исследований гидравлических характеристик системы АСО Qmaxс учетом адаптации для российских условий и нормативных требований, а также обоснование рекомендуемых параметров для их использования. In the context of the intensive development of new domestic and foreign technologies, materials and equipment used to protect the environment from anthropogenic pollution, the development of advanced systems for surface runoff removal and treatment is of special actuality. These systems provide for using the latest achievements of the sectoral science and optimizing the algorithm for performing operations and practical methods for the hydraulic calculations. An example of the innovative surface runoff disposal system is ASO Qmax, that refers to an open system of channels for the collection and disposal of surface runoff formed during precipitation. However, the widespread use of these facilities in Russia is hampered by the lack of a method for the hydraulic calculations, including tables for the selection of cross-sections (diameters) of channels that meet the requirements of the Russian guidelines and regulations for the design of surface runoff disposal systems. In this regard, the subject of this paper is the estimation of the hydraulic characteristics of pipelines, channels of ASO Qmax drainage system. The results of theoretical and experimental studies of the hydraulic characteristics of ASO Qmax system with account of the adaptation for the Russian conditions and regulatory requirements, as well as the justification of the recommended parameters for their use are presented.


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