scholarly journals Improvement of the Method of Calculation of Steady-State Modes of Urban Electric Networks Taking into Account Consumer Energy Sources

2019 ◽  
Vol 62 (6) ◽  
pp. 514-527
Author(s):  
M. I. Fursanov ◽  
A. A. Zalotoy
Keyword(s):  
Steady State ◽  
Low Voltage ◽  
Distribution Networks ◽  
Calculation Model ◽  
Automated System ◽  
Electric Networks ◽  
Steady State Mode ◽  
Power Sources ◽  
Electric Network ◽  
Method Of Calculation

The method of calculation of the steady-state mode of the open city distribution electric network with small generation sources is offered. It is shown that the city electric network consists of passive and active physical elements. Passive elements include power transformers and linear regulators, overhead and cable power lines, current-limiting reactors, etc. Active elements of networks are power sources (transformer inputs of low voltage of feeding substations and distributed small generation sources) and loads, mathematical models of which can be various. Power sources in urban distribution networks of 10 kV and below are classified by type and power and can be of two kinds, viz. power feeding centers of the network and small generation sources. Consumer loads are modeled by current sources connected to network nodes. The parameters of the current sources are usually graphs of the change of the module of the actual current value and the power factor in time. The values of these parameters in single-line substitution schemes of 6–10 kV distribution networks with isolated neutral are assumed to be average for three phases. The power centers are transformer inputs of low voltage power substations of the main electric networks of 35 kV and above, equipped with digital devices of the account of the electric power connected to the automated system of control and accounting of power resources. The developed technique allows receiving the refined balanced calculation model of the steady mode of the open city network for the set time of the daily schedule. It includes the sequential distribution of the specified power of each network power supply between its loads, followed by clarification of flows and power losses in the sections, as well as voltages and actual loads in the nodes of the scheme by the overlay method.

Analysis of operation of Oblkommunergo electric networks of Irkutsk Region

2021 ◽  
Vol 14 (3) ◽  
pp. 100-110
Author(s):  
I. V. Naumov
Keyword(s):  
Low Voltage ◽  
Average Duration ◽  
Electric Energy ◽  
Distribution Networks ◽  
Operational Reliability ◽  
Electrical Networks ◽  
Electric Networks ◽  
Public Media ◽  
Irkutsk Region ◽  
Graphic Editor

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.

scholarly journals On the choosing the installation location the balancing devices in low-voltage distribution electric networks

2021 ◽  
Vol 2094 (5) ◽  
pp. 052012
Author(s):  
I V Naumov ◽  
S V Podyachikh
Keyword(s):  
Power Quality ◽  
Low Voltage ◽  
Experimental Studies ◽  
Distribution Networks ◽  
Electrical Networks ◽  
Process Change ◽  
Electric Networks ◽  
Concentrated Load ◽  
Operating Modes ◽  
Three Phase

Abstract The experimental studies result on the power quality and additional power losses analysis caused by the asymmetric modes occurrence in three-phase four-wire 0.38 kV electrical networks are considered. The operating modes 38 kV networks several types simulation – with power take-off nodes distributed along the power line, and an electric network with a concentrated load is carried out. The programs have been developed that allow to assess the change in indicators characterizing asymmetric modes, as well as programs that allow us to visualize this process change. The most installing special symmetrical devices appropriate places in electric networks with a distributed load (rural electric distribution networks) and concentrated power take-off nodes electric networks (urban electric networks) have been identified to minimize losses and improve the power quality. A numerical studied indicators analysis was performed.

scholarly journals Investigation on Using Low Voltage Automatic Regulation to Minimize the Impacts of Charging Plug-in Electric Vehicles in Distribution Systems

2021 ◽  
Vol 19 ◽  
pp. 85-90
Author(s):  
Priscila Costa Nascimento ◽  
◽  
Michel Girotto de Oliveira ◽  
José Carlos M. Vieira
Keyword(s):  
Steady State ◽  
Electric Vehicles ◽  
Distribution System ◽  
Distribution Systems ◽  
Low Voltage ◽  
Electric Energy ◽  
Distribution Networks ◽  
Voltage Regulation ◽  
Automatic Regulation ◽  
Electric Energy Storage

The growth of micro and mini distributed generation and, more recently, the use of electric energy storage systems and the incentives for electric mobility are important examples of the transformations that distribution networks have been going through. In this context, this paper firstly presents the impacts of uncoordinated plug-in electric vehicles (PEVs) charging in a real Brazilian distribution system. Four scenarios were elaborated with different PEVs penetration levels and the results show increased voltage unbalance, system losses, and violations of the steady-state voltage limits, even in the presence of an automatic voltage regulator installed in the medium voltage network. Then, as the main contribution, the potential usage of automatic voltage regulation at the low voltage network was investigated to minimize the negative impacts of uncontrolled PEV charging on distribution system steady-state operation. It is important to highlight that this is not a common practice of utilities in Brazil. The obtained results showed that regulating the voltage at the low voltage side could be an effective solution to keep the voltages within statutory limits.

scholarly journals Enhancing reliability of electricity supply of city electric networks cities of Dushanbe

2021 ◽  
Vol 10 (1) ◽  
pp. 46-54
Author(s):  
Alexander Ivanovich Sidorov ◽  
Saidjon Tavarov
Keyword(s):  
Power Consumption ◽  
Control Algorithm ◽  
Electrical Equipment ◽  
Distribution Networks ◽  
Smart Power ◽  
Electric Networks ◽  
Actual Problem ◽  
Local Conditions ◽  
Electric Network ◽  
Power Metering

The article is devoted to the actual problem of how to improve the reliability of the urban electric network. Based on the statistical analysis of the breakdown of electrical equipment in urban distribution networks in Dushanbe for the periods of 2017-2018 and for the reasons of damage leading to these emergency outages, the factors that affect the distribution of damage leading to emergency outages are identified. Taking into account the identified factors, a power consumption forecasting system is proposed that takes into account the local conditions of the city of Dushanbe. it allows us to suggest a way to control the operating parameters of the electric network, thereby increasing the reliability of the city's electric network in Dushanbe based on the recommendation of power consumption standards. Implementation of the control of the proposed method for improving the reliability of power supply to the urban electric network is proposed on the basis of the functionality of modern smart electricity metering using the control algorithm. To implement the control algorithm, schematic design for receiving and transmitting information from smart power metering to the data collection centre is proposed.

scholarly journals Simulation of Electric Networks Modes Using Steady-State and Heat Balance Equations

2020 ◽  
Vol 63 (1) ◽  
pp. 66-80
Author(s):  
A. B. Balametov ◽  
E. D. Halilov
Keyword(s):  
Steady State ◽  
Ambient Temperature ◽  
Temperature Dependence ◽  
Test System ◽  
Temperature Correction ◽  
Electrical Network ◽  
Overhead Line ◽  
Power Losses ◽  
Steady State Mode ◽  
Electric Network

In the traditional calculations of the steady-state mode of the electrical network, the dependences of the active resistances of the overhead line wire on the ambient temperature and currents in the branches are not taken into account. However, the temperature is a function of the active power losses, the power losses are a function of the resistance and current, and the resistance is temperature dependent. Therefore, these relations should be related to the traditional equations for stationary regimes. In order to increase the accuracy of steady-state calculations, a temperature correction of the resistance of the branches is required. In this paper, we present a method based on the joint solution of nonlinear equations of the steady-state electric network regime and the thermal balance of the wires of overhead lines. The algorithm and the program of calculation of the steady-state mode of an electric network taking into account dependence of active resistances of a wire of an overhead line on ambient temperature and currents in branches have been developed. The quantitative influence of the load current, wire temperature, wind speed, solar radiation on the active resistance of the wires has been estimated, and the errors in calculating annual variable energy losses have been determined. Numerical experiments were carried out for a 6-node modified version of the IEEE test system and equivalent circuit of 110 kV. The results of the calculations of the steady-state regime on various test circuits showed that the non-account of the temperature dependence of the active resistances might cause errors in power loss for individual loaded lines up to 10 %, and for total losses of the system – up to 30 %. This is unacceptable in simulating the modes of the electric network. The results of simulation of steady-state regimes taking into account the temperature dependence of the resistance of the wires are presented on the example of 6-node and 7-node circuits.

scholarly journals Improving the efficiency of distribution electric networks of railways based on the multi-agent mode management method

Vestnik IGEU ◽  
2019 ◽  
pp. 54-63
Author(s):  
V.T. Cheremisin ◽  
E.A. Tretyakov
Keyword(s):  
Flow Control ◽  
Power Flow ◽  
Distribution Networks ◽  
Electrical Network ◽  
Distributed Objects ◽  
Electric Networks ◽  
Power Sources ◽  
Power Flow Control ◽  
Multi Agent ◽  
Agent Control

With the increase in observability and controllability of regimes, the development of methods for managing distributed objects of the electrical network is becoming more and more important. The main research directions in smart grids are based on the theory of fuzzy sets, genetic algorithms, neural networks, stochastic control, spectral graph, bilinear matrix inequality constraints. They are aimed at solving multicriterion optimization problems of electric networks with distributed objects and are computationally-demanding and time-consuming. Meanwhile, the methods of multi-agent control of the power supply system based on the parallelization of information flows and coordination of the operation of distributed linear regulators are becoming more common. The purpose of this study is to develop methods for controlling the operating modes of smart distribution electric networks of railways using an agent-based approach for stabilizing voltages within specified limits and reducing electric power losses. This goal can be achieved by solving the problems of developing an algorithm for managing power flows based on the coordinated work of active and reactive power sources and principles of demand management of active consumers. The multi-agent power flow control was realized in the AnyLogic program, the simulation modeling of the electrical network modes was performed in Matlab Simulink with assumptions of linear characteristics of voltage loads. A method has been developed to control the operation modes of smart distribution electric networks of railways based on the presented power flow control algorithm, the hallmarks of which are the use of linearized equations for determining control actions in small increments, which allows high speed data analysis in real time without calculating steady-state modes with disturbances. The obtained simulation results prove the validity of power flow control methods for voltage stabilization based on multi-agent control and the possibility of their practical implementation on modern equipment in smart distribution networks of railways.

scholarly journals Formation of the Z-form of equations of steady-state modes of energy systems’ complex electric networks

2018 ◽  
Vol 58 ◽  
pp. 02021 ◽  
Author(s):  
Dauren Akhmetbayev ◽  
Arman Akhmetbayev ◽  
Assemgul Zhantlessova
Keyword(s):  
Steady State ◽  
Energy Systems ◽  
Distribution Coefficients ◽  
Data Preparation ◽  
Electric Networks ◽  
Steady State Mode ◽  
Level Of Automation ◽  
Direct Formation ◽  
The Matrix ◽  
Calculation Algorithms

This paper describes the state of the methodological problem of calculating steady-state modes of energy systems’ complex electric networks. It also describes the topological method of forming the Z-form of equations of steady-state modes of complex electric networks. The analytical dependence of the node impedance matrix with the matrix of the nodal currents distribution coefficients is established. The matrix of infeed coefficients is determined during the initial data preparation. An analytical approach for determining infeed coefficients topological essence is considered. A simplified method for calculating the driving current distribution coefficients is proposed based on all possible graph trees of a complex electric network. An algorithm for forming infeed coefficients matrix in the environment is developed. A technique for obtaining real solutions of the steady-state mode equations is developed. Steady-state modes direct formation significantly reduces the amount of work performed, increases the visibility of the calculation algorithms performance, and ensures fast and reliable iteration convergence. Increases the level of automation and efficiency of the calculations performed.

scholarly journals Multidisciplinary Approach for the Development of Smart Distribution Networks

2018 ◽  
Author(s):  
Emilio Ghiani ◽  
Alessandro Serpi ◽  
Virginia Pilloni ◽  
Giuliana Sias ◽  
Marco Simone ◽  
...  
Keyword(s):  
Power Systems ◽  
Power Distribution ◽  
Low Voltage ◽  
Distribution Networks ◽  
Power Distribution Networks ◽  
Electric Networks ◽  
Fully Integrated ◽  
Manual Intervention ◽  
New Energy ◽  
Information Engineering

Electric power systems are experiencing relevant changes involving the growing penetration of distributed generation and energy storage systems, the introduction of electric vehicles, the management of responsive loads, the proposals for new energy markets and so on. Such evolution is pushing for a paradigm shift: the management must move from traditional planning and manual intervention to full “smartization” of medium and low voltage networks. Peculiarities and criticalities of future power distribution networks originate from the complexity of the system that includes both the physical aspects of electric networks and the cyber aspects, like data elaboration, feature extraction, communication, supervision and control; only fully integrated advanced monitoring systems can foster this transition towards network automation. The design and development of such future networks require distinct kinds of expertise in the industrial and information engineering fields. In this context, this paper provides a comprehensive review of current challenges and multidisciplinary interactions in the development of smart distribution networks.

scholarly journals A Multidisciplinary Approach for the Development of Smart Distribution Networks

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2530 ◽  
Author(s):  
Emilio Ghiani ◽  
Alessandro Serpi ◽  
Virginia Pilloni ◽  
Giuliana Sias ◽  
Marco Simone ◽  
...  
Keyword(s):  
Power Systems ◽  
Power Distribution ◽  
Network Architecture ◽  
Low Voltage ◽  
Distribution Networks ◽  
Power Distribution Networks ◽  
Electric Networks ◽  
Fully Integrated ◽  
New Energy ◽  
Smart Distribution Network

Electric power systems are experiencing relevant changes involving the growing penetration of distributed generation and energy storage systems, the introduction of electric vehicles, the management of responsive loads, the proposals for new energy markets and so on. Such an evolution is pushing a paradigm shift that is one of the most important challenges in power network design: the management must move from traditional planning and manual intervention to full “smartization” of medium and low voltage networks. Peculiarities and criticalities of future power distribution networks originate from the complexity of the system which includes both the physical aspects of electric networks and the cyber aspects, like data elaboration, feature extraction, communication, supervision and control; only fully integrated advanced monitoring systems can foster this transition towards network automation. The design and development of such future networks require distinct kinds of expertise in the industrial and information engineering fields. In this context, this paper provides a comprehensive review of current challenges and multidisciplinary interactions in the development of smart distribution networks. The aim of this paper is to discuss, in an integrated and organized manner, the state of the art while focusing on the need for interaction between different disciplines and highlighting how innovative and future-proof outcomes of both research and practice can only emerge from a coordinated design of all the layers in the smart distribution network architecture.

Sign in / Sign up

Export Citation Format

Share Document