scholarly journals Choice of commutation device and development of the scheme of a universal sectionalizing point with automatic load transfer function for the 0.38 kV electric network

2019 ◽  
Vol 124 ◽  
pp. 02011 ◽  
Author(s):  
A. V. Vinogradov ◽  
A. V. Vinogradova ◽  
M. O. Ward ◽  
A. N. Kharkhardin ◽  
A. I. Psaryov ◽  
...  
Keyword(s):  
Transfer Function ◽  
Power Supply ◽  
Load Transfer ◽  
Power Source ◽  
Power Lines ◽  
Electrical Networks ◽  
Transformer Substation ◽  
Load Transfer Function ◽  
Short Circuits ◽  
Switching Devices

The overestimated length of rural power lines of 0.38 kV leads to the fact that it is often not possible to fulfill both the sensitivity conditions of the protective device installed at the transformer substation and protecting the line from overloads and short circuits, and the requirements of the power supply reliability of consumers. This problem can be solved by installing in-line universal sectionalizing point equipped with an automatic load transfer function. The use of these devices allows dividing a line into sections provides the necessary sensitivity of protection for each section of the line and the possibility of supplying power to undamaged areas from a backup power source. In addition, only with the use of automated switching devices installed in power lines, it is possible to create intelligent electrical networks. When developing these devices, it is necessary to take into account the electromechanical characteristics of switching devices that are planned to be used for switching lines.

scholarly journals Proposed point bearing load transfer function in jointed rock-socketed drilled shafts

2013 ◽  
Vol 53 (4) ◽  
pp. 596-606 ◽  
Author(s):  
Jaehwan Lee ◽  
Kwangho You ◽  
Sangseom Jeong ◽  
Jaeyoung Kim
Keyword(s):  
Transfer Function ◽  
Load Transfer ◽  
Jointed Rock ◽  
Drilled Shafts ◽  
Bearing Load ◽  
Load Transfer Function

scholarly journals Design of power substation placement with GIS tracing tools

Vestnik IGEU ◽  
2019 ◽  
pp. 75-83 ◽  
Author(s):  
А.В. Gadalov ◽  
S.V. Kosyakov
Keyword(s):  
Low Voltage ◽  
Power Grid ◽  
Distribution Networks ◽  
Power Lines ◽  
Electrical Networks ◽  
Voltage Distribution ◽  
Transformer Substation ◽  
Urban Distribution ◽  
Gis Environment

Analytical methods that are currently used to determine transformer substation placement in the process of planning the development of low-voltage distribution networks are based on calculating the lengths of future power lines by Euclidean distance, or methods for comparing several alternative placement options taking into account the routes of power lines. Assumptions made in this case lead to the fact that for the selected location of the substation, the total cost of the power lines connected to it may exceed the possible minimum. The use of modern GIS technologies allows simulating the routes of laying power lines on the map bypassing the existing obstacles or finding the cheapest routes for crossing them. These opportunities can be used to improve the quality of designing urban distribution networks through minimizing the construction cost of new power lines. However, the methods of organizing the solution to such a design problem have not yet found practical applications. The aim of the work is to develop a practical method of designing the placement of power substations in the GIS environment and its verification using real data. The paper uses methods of spatial modeling in the GIS environment, including methods of overlay, finding optimal paths on graphs and power grid inventory, as well as discrete optimization methods. A method of computer-aided design of transformer substation placement in urban distribution low-voltage networks is proposed and implemented as a GIS software module, which allows finding the optimal options of the placement cost at the stages of network scheme selection. The paper presents the results of the method analysis based on studying the design of the power grid scheme of Ivanovo city quarters as an example. The results confirm the possibility of using GIS to improve the quality of decisions on the choice of placement of low voltage distribution substations when designing urban electrical networks and can be used in the electrical networks CAD.

scholarly journals Increasing the parameters of electrical distribution networks of town districts with low load density

2020 ◽  
Vol 1 (57) ◽  
pp. 28-32
Author(s):  
V. Perepecheny
Keyword(s):  
Power Supply ◽  
Distribution Networks ◽  
Voltage Regulation ◽  
Parameter Distribution ◽  
Electrical Networks ◽  
Supply Networks ◽  
Transformer Substation ◽  
Low Load ◽  
The Impact ◽  
Selection Of

This article presents the results of research on the parameters of electrical networks with a voltage of 6 (10) and 0.38 kV in relation to capital investments. The analysis of existing methods of estimation of parameters before designing for power supply networks in a small town with low load density is carried out. In modern conditions, in the distribution of electrical networks is of paramount importance the introduction of energy-saving schemes and parameters of power supply systems. One of the main ways to implement them is to increase the efficiency of 6-10 / 0.38 kV networks. In the actual design of electrical networks, economic proportionality can not always be maintained for various reasons: the impact of technical constraints, the discreteness of the rated power of transformers and cable crossing scales, a significant deviation of individual capacities of consumers from the average value. In that case there is an increase in the reduced costs. A methodology for determining the optimal power of transformer substations and optimal sections of 0.38 kV power transmission lines is proposed, taking into account the probable nature of the applied load. When assembling the power supply circuit for the optimal form of parameters, voltage, principles of voltage regulation and reactive power compensation. Decisions of this kind are substantiated by technical and economic comparisons of a series of technically acceptable variants of power supply networks. An important measure that facilitates the selection of the most economical option is the assessment of the proposed project, which relates to the selection of the optimal capacity of transformer substation (TS) networks using calculation formulas. The aim of the research was to improve the existing methods on the basis of separate accounting of the reliability coefficient of 0.38 kV and 6-10 kV network. Key words - electric power supply network, network parameters, transformer substation, load density, line wire section, specific load, unit costs, optimum parameter, distribution networks, electric energy.

scholarly journals Studi Daya Dukung Fondasi Tiang Pada Tanah Lempung Teguh Berdasarkan Pembebanan Kepala Tiang Dan Pergerakan Ujung Tiang Metode T-Z

2020 ◽  
Vol 3 (2) ◽  
pp. 88
Author(s):  
Mochamad fikri firmansyah Fikri Firmansyah ◽  
Rakha Fausta ◽  
Helmy Darjanto
Keyword(s):  
Shear Strength ◽  
Transfer Function ◽  
Bearing Capacity ◽  
Surface Properties ◽  
Pile Foundation ◽  
Load Transfer ◽  
Load Transfer Function

Developments in the calculation of foundation planning today have produced many methods and formulas for calculating the bearing capacity of foundations, such as the T-Z method, the Tezaghi method, the Mayerhof method, the Tomlison method, and other methods. So the purpose of this study was to determine the bearing capacity from tip movement of the foundation of each load with the T-Z method. The T-Z method explains rationally the mechanism of load transfer using a load transfer function commonly called TZ. In this method the pile foundation will be divided into several segments and the transfer function on each side segment which is a function of the shear strength of the soil and the surface properties of the side pile. From the analysis results of the TZPILE application, the bearing capacity is due to the settlement. At a settlement of 0,0001m; 0.001m; 0.0015m; 0.0025m; and 0.005m get a bearing capacity of 4.31kN; 31.69 kN; 35.6 kN; 43.44 kN; and 60.10kN. And on the reduction of permits on the foundation that occurs according to SNI 8460 - 2017 is 25mm, so the analysis obtained 12mm which still meets the requirements, 12mm get a bearing capacity of 1200kN at the tip of the pile. At a load of 600 kn the head of the pile can be held at a depth 4 meters. And for the maximum bearing capacity of the 18 meter pole, it can whitstand a bearing capacity of 1200 kn.

scholarly journals Substantiation of the choice of the replacement scheme of line for mathematical modeling of 20 kV power supplies.

2021 ◽  
Vol 24 (1) ◽  
pp. 69-72
Author(s):  
SKRYPNYK S. ◽  
Keyword(s):  
Power Systems ◽  
Transmission Lines ◽  
Power Supply ◽  
Electrical Equipment ◽  
Distribution Networks ◽  
Power Line ◽  
Power Lines ◽  
Electrical Networks ◽  
Overhead Lines ◽  
Replacement Scheme

In the current global economic crisis and acute shortage of energy resources, increasing importance is attached to energy saving measures, economical and careful consumption of raw materials, materials, electricity and heat, environmental safety of industrial production. During the reconstruction of existing power supply systems of industrial enterprises, modern progressive solutions should be considered and implemented, morally and physically obsolete electrical equipment should be replaced, namely the introduction of new electrical equipment for transition from 6/10 kV to 20 kV in Ukrainian power systems. It is also necessary to pay attention to the improvement of power supply circuits and distribution networks, the implementation of complex automation of complex technological processes, rational compensation of reactive power at all levels of power supply systems. In the power system, the main transport link is the power line. Power lines (transmission lines) are long conductors suspended at a safe distance from the ground overhead lines (overhead lines) or cable lines (overhead lines) in which conductors are insulated from each other and from the environment and protected by insulation and armor electricity. Power lines are the most massive elements of the power supply system, they connect the individual nodes of its circuit. Longitudinal and transverse parameters are distinguished in alternative schemes. The load current flows through the longitudinal parameters, voltage is applied to the transverse ones. The replacement circuit of the electrical network consists of replacement circuits of the following elements: power lines, transformers, reactors, capacitors, loads, power sources. Calculating the steady-state modes of power systems, the substitution schemes of the elements are given in a single-line design, because the parameters of all phases are symmetrical. In local and local electrical networks with a relatively short length and low rated voltage, the conduction currents are small compared to load currents. Therefore, in typical electrical calculations of these networks, the capacitive conductivity of the lines is not taken into account. However, for these networks, the accounting of capacitive conductivities is necessary when considering some modes, the existence of which in itself is due only to the presence of capacitive conductivities. For example, the mode of single-phase ground fault in a network with isolated or compensated neutral or analysis of the modes of operation of neutrals of electrical networks of different voltage classes cannot be performed without taking into account the capacitive conductivity of these networks. When switching the power system of Ukraine to the nominal voltage of 20 kV, it should be taken into account that the transmission line will be replaced in the sections of both the overhead power line and cable power line, namely 35, 10, 6 kV. The replacement scheme must describe all the characteristics and properties of the elements of cable and overhead lines in accordance with real conditions. Thus, it is not expedient to use simplified substitution circuits that neglect energy parameters and properties of conductors to study the parameters of transmission lines. The use of a complete "P" -shaped scheme for the analysis of the parameters of transmission lines and transmission lines for a voltage of 20 kV is the basis of mathematical modeling of the transmission system in the distribution networks of our country.

scholarly journals Solving optimization problems when designing power supply circuits

2019 ◽  
Vol 124 ◽  
pp. 04011 ◽  
Author(s):  
O. V. Shemelova ◽  
E. V. Yakovleva ◽  
T. G. Makuseva ◽  
I. I. Eremina ◽  
O. N. Makusev
Keyword(s):  
Electric Power ◽  
Power Supply ◽  
Optimization Problems ◽  
Cost Minimization ◽  
Mathematical Problem ◽  
Power Lines ◽  
Practical Significance ◽  
Electrical Network ◽  
Power Network ◽  
Electrical Networks

One of the quickly developing trends in the optimization of electric power grids is system development of operation and optimization of branch circuits which are based on linear programming problems. One of its categories is traffic problem. The paper discusses the formulation of various types of transport optimization problems used in the design of the most efficient power supply systems in the real sector of economy. The construction of arithmetic models of problems is carried out. Their optimality criterion is cost minimization for the design of electrical network diagrams consisting of power lines connecting sources and consumers. Examples of designing optimization power layout in mathematical problems considering the transmission capacity of power lines is given. The paper also touches upon a mathematical problem considering possible transit of capacities. The task is to build a mathematical model and solve problems that ensure minimization of process losses and losses of power when designing electrical networks. The results of solving problems are presented in the form of power supply circuits corresponding to the most optimal linking of source and consumer nodes. The work is of a scientific and practical significance as it considers the problem of optimizing economic costs when designing electric power network schemes. Moreover it is based on a qualitatively different level of use of the traffic problem algorithm. The algorithm for solving the minimization problem obtained in this paper allows developing the necessary computing operations as well as quickly obtaining the results of solving the cost optimization problem in the designed electric power network.

scholarly journals Analytical Model and Back-Analysis for Pile-Soil System Behavior under Axial Loading

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Hong-Fa Xu ◽  
Ji-Xiang Zhang ◽  
Xin Liu ◽  
Han-Sheng Geng ◽  
Ke-Liang Li ◽  
...  
Keyword(s):  
Transfer Function ◽  
Analytical Model ◽  
Axial Force ◽  
Load Transfer ◽  
Back Analysis ◽  
Axial Loading ◽  
Distribution Functions ◽  
Soil System ◽  
Relationship Model ◽  
Load Transfer Function

The interaction mechanism between piles and soils is very complicated. The load transfer function is generally nonlinear and is affected by factors such as pile side roughness, soil characteristics, section depth, and displacement. Therefore, it is difficult to solve the pile-soil system based on load transfer function. This paper presents a new method to study the soil-pile interaction problem with respect to axial loads. First, the shapes of the axial force-displacement curves at different depths and the displacement distribution curves along pile axis at different pile-top displacements were analyzed. A simple exponential function was taken as relationship model to express the relationship curves between two distribution functions of axial force and displacement along pile shaft obtained by using the geometric drawing method. Second, a new analytical model of the pile-soil system was established based on the basic differential equations for pile-soil load transfer theory and the relationship model and was used to derive the mathematical expressions on the distribution functions of the axial force, the lateral friction, and the displacement along pile shaft and the load transfer function of pile-side. We wrote the MATLAB program for the analytical model to analyze the influence laws of the parameters u and m on the pile-soil system characteristics. Third, the back-analysis method and steps of the pile-soil system characteristics were proposed according to the analytical model. The back-analysis results were in good agreement with the experimental results for the examples. The analysis model provides an effective way for the accurate design of piles under axial loading.

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