scholarly journals Active Distribution Network Modeling for Enhancing Sustainable Power System Performance; a Case Study in Egypt

2020 ◽  
Vol 12 (21) ◽  
pp. 8991
Author(s):  
Ali A. Radwan ◽  
Ahmed A. Zaki Diab ◽  
Abo-Hashima M. Elsayed ◽  
Hassan Haes Alhelou ◽  
Pierluigi Siano

The remarkable growth of distributed generation (DG) penetration inside electrical power systems turns the familiar passive distribution networks (PDNs) into active distribution networks (ADNs). Based on the backward/forward sweep method (BFS), a new power-flow algorithm was developed in this paper. The algorithm is flexible to handle the bidirectional flow of power that characterizes the modern ADNs. Models of the commonly used distribution network components were integrated with the developed algorithm to form a comprehensive tool. This tool is valid for modeling either balanced or unbalanced ADNs with an unlimited number of nodes or laterals. The integrated models involve modeling of distribution lines, losses inside distribution transformers, automatic voltage regulators (AVRs), DG units, shunt capacitor banks (SCBs) and different load models. To verify its validity, the presented algorithm was first applied to the unbalanced IEEE 37-node standard feeder in both passive and active states. Moreover, the algorithm was then applied to a balanced 22 kV real distribution network as a case study. The selected network is located in a remote area in the western desert of Upper Egypt, far away from the Egyptian unified national grid. Accordingly, the paper examines the current and future situation of the Egyptian electricity market. Comparison studies between the performance of the proposed ADNs and the classical PDNs are discussed. Simulation results are presented to demonstrate the effectiveness of the proposed ADNs in preserving the network assets, improving the system performance and minimizing the power losses.

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4125
Author(s):  
Miguel Carrión ◽  
Rafael Zárate-Miñano ◽  
Ruth Domínguez

The expected growth of the number of electric vehicles can be challenging for planning and operating power systems. In this sense, distribution networks are considered the Achilles’ heel of the process of adapting current power systems for a high presence of electric vehicles. This paper aims at deciding the maximum number of three-phase high-power charging points that can be installed in a low-voltage residential distribution grid. In order to increase the number of installed charging points, a mixed-integer formulation is proposed to model the provision of decentralized voltage support by electric vehicle chargers. This formulation is afterwards integrated into a modified AC optimal power flow formulation to characterize the steady-state operation of the distribution network during a given planning horizon. The performance of the proposed formulations have been tested in a case study based on the distribution network of La Graciosa island in Spain.


2018 ◽  
Vol 53 ◽  
pp. 02013 ◽  
Author(s):  
Zhe Chen ◽  
Haiyun An ◽  
Ze Sun ◽  
Bingcheng Cen ◽  
Si Li

The smart grid is the latest trend and complex scientific issue in the development of power systems in the world today. With the new round of power system reform and the deregulation of the power market, comprehensive and scientific evaluation of the development level of the smart grid plays an important role in achieving the overall goal of smart grid construction. This paper constructed a comprehensive evaluation index system from the aspects of safety and reliability, economy, intelligence level and sustainability of smart distribution network. Then the comprehensive evaluation model of AHPTOPSIS intelligent distribution network was established. Finally, an empirical study on the development level of smart distribution networks of four power companies in a province was carried out, and corresponding conclusions were drawn.


2020 ◽  
Author(s):  
Wandry R. Faria ◽  
Jonas V. Souza ◽  
Rodrigo B. Otto ◽  
Benvindo R. Pereira Jr.

The growing number of decentralized generators in the distribution systems and the consequent increase in the penetration level in the networks have prompted the inclusion of this scenario in researches involving the planning of electrical power systems. The planning of protection systems for distribution networks considering distributed generators requires adaptations in the approach due to modifications in characteristics of the network, such as passivity and unidirectional power flow. Furthermore, the insertion of generators in distribution networks allows the implementation of new operation methods, such as the possibility of disconnecting some loads from the main feeder and supplying them through distributed generators. The island operation can improve the service continuity indexes, as well as reduce the costs of non-supplied energy. Although the island operation is widely proposed in the literature as a means to improve the system's reliability, the simulation of a protective device to intentionally island a region and the verification of its limitations is not. In this paper, we present the modeling of a directional overcurrent relay through ATP-EMTP, and its employment as a device for island interconnection, analyzing its zone of non-operation. CIGRE 14-bus test system is used to conduct short-circuit tests with the variation of resistance and type of fault applied. Theresults show the effectiveness of the device, which is able to identify all faults with real impact on the network, placing the region in island operation in less than 20 ms.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3253
Author(s):  
Alex Valenzuela ◽  
Silvio Simani ◽  
Esteban Inga

Electrical power systems represent a fundamental part of society, and their efficient operations are of vital importance for social and economic development. Power systems have been designed to withstand interruptions under already provided safety and quality principles; however, there are some extreme and not so frequent events that could represent inconveniences for the correct operation of the entire system. For this reason, in recent years the term resilience, which serves to describe the capacity of a system to recover from an unwanted event, has been analyzed on planning, operation and remedial actions. This work is focused on the implementation of a topological reconfiguration tool, which is oriented to change the structure of primary feeders based on changing the status of switchgears. Once the distribution network has been reconfigured, an algorithm of protection coordination is executed based on communication peer-to-peer between Matlab and PowerFactory, which develops an adaptive calculation to determine the current setting and the time multiplier setting. The reconfiguration and coordination protection algorithms could be implemented and evaluated on different distribution networks, areas and locations.


2021 ◽  
Vol 25 (02) ◽  
pp. 78-87
Author(s):  
Ihsan M. Jawad ◽  
◽  
Wafaa S. Majeed ◽  

In electrical power systems, unexpected outage of transmission systems, sudden increase of loads, the exit of generators from service, and equipment failure, leads to a contingency occurring on one or several transmission lines. The loads must be within the specified state and the transmission lines should not exceed the thermal limits. One of the important methods used to alleviate the contingency and reduce the congestion lines by injected a Distributed Generation (DG) within an optimal siting and optimal sizing in the distribution network that achieves improvement of the voltage profile as well as leads to reduce the losses. First, to achieve the best goals in this paper that is determined contingency lines, an index has been used called (Active Power Flow Performance Index) (PIRPF) and an equation called (Line Flow Sensitivity Index) (LFSI) is used for finding the optimum site for Distributed Generation. Second, to determine the optimum size for distributed generators, the Genetic Algorithm (GA) is used. Also, this research was distinguished by choosing new sites and sizes according to the GA to obtain the best desired results. Finally, these methodologies were applied to the IEEE-30 bus ring network using the MATPOWER Version 6.0, 16-Dec-2016 program within MATLAP R2018a environment.


2020 ◽  
Vol 181 ◽  
pp. 03006
Author(s):  
Nduwamungu Aphrodis ◽  
Ntagwirumugara Etienne ◽  
Utetiwabo Wellars ◽  
Mulolani Francis

Faults in electrical power systems are among the key factors and sources to network disturbances, however control strategies are among key faults clearing techniques for the sake of safe operational mode of the system.Some researchers have shown various limitations of control strategies such as slow dynamic response,inability to switch Off and On network remotely and fault clearing time. For a system with wind energy technologies, if the power flow of a wind turbine is interrupted by a fault, the intermediate-circuit voltage between the machine-side converter and line-side converter will fall in unacceptably high values.To overcome the aforementioned issues, this paper used a Matlab simulations and experiments in order to analyze and validate the results.The results showed that fault ride through (FRT) with SCADA Viewer software are more adaptable to the variations of voltage and wind speed in order to avoid loss of synchronism. Therefore at the speed of 12.5m/s a wind produced a rated power of 750W and remained in synchronization before and after a fault created and cleared but worked as generator meanwhile at speed of 3.4m/s wind disconnected from grid and started working as a motor and consumed active power (P=-25watts) and voltage dip at 100% .For the protection purpose, the DC chopper and crowbar should be integrated towards management of excess energy during faults cases.


2020 ◽  
Vol 34 (01) ◽  
pp. 630-637 ◽  
Author(s):  
Ferdinando Fioretto ◽  
Terrence W.K. Mak ◽  
Pascal Van Hentenryck

The Optimal Power Flow (OPF) problem is a fundamental building block for the optimization of electrical power systems. It is nonlinear and nonconvex and computes the generator setpoints for power and voltage, given a set of load demands. It is often solved repeatedly under various conditions, either in real-time or in large-scale studies. This need is further exacerbated by the increasing stochasticity of power systems due to renewable energy sources in front and behind the meter. To address these challenges, this paper presents a deep learning approach to the OPF. The learning model exploits the information available in the similar states of the system (which is commonly available in practical applications), as well as a dual Lagrangian method to satisfy the physical and engineering constraints present in the OPF. The proposed model is evaluated on a large collection of realistic medium-sized power systems. The experimental results show that its predictions are highly accurate with average errors as low as 0.2%. Additionally, the proposed approach is shown to improve the accuracy of the widely adopted linear DC approximation by at least two orders of magnitude.


2013 ◽  
Vol 07 (02) ◽  
pp. 1350005 ◽  
Author(s):  
GIAN PAOLO CIMELLARO ◽  
ALESSANDRO DE STEFANO ◽  
OMAR VILLA

The concept of disaster resilience has received considerable attention in recent years and it is increasingly used as an approach for understanding the dynamics of natural disaster systems. No models are available in literature to measure the performance of natural gas network, therefore, in this paper, a new performance index measuring functionality of gas distribution network have been proposed to evaluate the resilience index of the entire network. It can be used for any type of natural or manmade hazard which might lead to the disruption of the system. The gas distribution network of the municipalities of Introdacqua and Sulmona, two small towns in the center of Italy which were affected by 2009 earthquake have been used as case study. Together the pipeline network covers an area of 136 km2, with 3 M/R stations and 16 regulation groups. The software SynerGEE has been used to simulate different scenario events. The numerical results showed that, during emergency, to ensure an acceptable delivery service, it is crucial to guarantee the functionality of the medium pressure gas distribution network. Instead to improve resilience of the entire network the best retrofit strategy is to include emergency shutoff valves along the pipes.


Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 573
Author(s):  
Mohamed Mokhtar ◽  
Mostafa I. Marei ◽  
Mariam A. Sameh ◽  
Mahmoud A. Attia

The frequency of power systems is very sensitive to load variations. Additionally, with the increased penetration of renewable energy sources in electrical grids, stabilizing the system frequency becomes more challenging. Therefore, Load Frequency Control (LFC) is used to keep the frequency within its acceptable limits. In this paper, an adaptive controller is proposed to enhance the system performance under load variations. Moreover, the proposed controller overcomes the disturbances resulting from the natural operation of the renewable energy sources such as Wave Energy Conversion System (WECS) and Photovoltaic (PV) system. The superiority of the proposed controller compared to the classical LFC schemes is that it has auto tuned parameters. The validation of the proposed controller is carried out through four case studies. The first case study is dedicated to a two-area LFC system under load variations. The WECS is considered as a disturbance for the second case study. Moreover, to demonstrate the superiority of the proposed controller, the dynamic performance is compared with previous work based on an optimized controller in the third case study. Finally in the fourth case study, a sensitivity analysis is carried out through parameters variations in the nonlinear PV-thermal hybrid system. The novel application of the adaptive controller into the LFC leads to enhance the system performance under disturbance of different sources of renewable energy. Moreover, a robustness test is presented to validate the reliability of the proposed controller.


Author(s):  
Tahir Cetin Akinci

The production, transmission, and distribution of energy can only be made stable and continuous by detailed analysis of the data. The energy demand needs to be met by a number of optimization algorithms during the distribution of the generated energy. The pricing of the energy supplied to the users and the change for investments according to the demand hours led to the formation of energy exchanges. This use costs varies for active or reactive powers. All of these supply-demand and pricing plans can only be achieved by collecting and analyzing data at each stage. In the study, an electrical power line with real parameters was modeled and fault scenarios were created, and faults were determined by artificial intelligence methods. In this study, both the power flow of electrical power systems and the methods of meeting the demands were investigated with big data, machine learning, and artificial neural network approaches.


Sign in / Sign up

Export Citation Format

Share Document