Overview of electric energy distribution networks expansion planning

Planning of the electric distribution networks is complex and about upgrading the system to satisfy the demand and constraints with the best economic plan. The planning alternatives include the expansion of substations, installing new distributed generation (DG) facilities, upgrading distribution feeders, etc. In the modern networks, distribution planners must gain the confidence of the reversibility of the investment where renewable energy resources (RERs) inject clean and cost-effective electrical power to respond to the rising demand and satisfy environmental standards. This paper is an exhaustive review on the distribution network expansion planning (DEP) including the modelling of DEP (possible objective functions, problem constraints, different horizon time, and problem variables), optimization model (single/multi-objective), the expansion of distributed energy resources (DERs), problem uncertainties, etc. We discuss the requirements of integrated energy district master planning to avoid conflicts between the goal of independence of district planning on energy, e.g. heat and electricity, and that of dependencies on the local electric utilities regarding instant power balance and stability services. Finally, we describe the primary future R&D trends in the field of distribution network planning

Heuristic for solving capacitor allocation problems in electric energy radial distribution networks

The goal of the capacitor allocation problem in radial distribution networks is to minimize technical losses with consequential positive impacts on economic and environmental areas. The main objective is to define the size and location of the capacitors while considering load variations in a given horizon. The mathematical formulation for this planning problem is given by an integer nonlinear mathematical programming model that demands great computational effort to be solved. With the goal of solving this problem, this paper proposes a methodology that is composed of heuristics and Tabu Search procedures. The methodology presented explores network system characteristics of the network system reactive loads for identifying regions where procedures of local and intensive searches should be performed. A description of the proposed methodology and an analysis of computational results obtained which are based on several test systems including actual systems are presented. The solutions reached are as good as or better than those indicated by well referenced methodologies. The technique proposed is simple in its use and does not require calibrating an excessive amount of parameters, making it an attractive alternative for companies involved in the planning of radial distribution networks

Ant colony system-based applications to electrical distribution system optimization

Chapter 16, February 201

Renewable Energy Storage System Based on a Power-to-Gas Conversion Process

Abstract The increasing penetration of renewable energy generation in the electric energy market is currently posing new critical issues, related to the generation prediction and scheduling, due to the mismatch between power production and utilization. In order to cope with these issues, the implementation of new large scale storage units on the electric network is foreseen as a key mitigation strategy. Among large scale technologies for the electric energy storage, the Power-to-Gas solution can be regarded as a long-term viable option, provided that the conversion efficiency is improved and aligned with other more conventional storage alternatives. In this study, a Power-to-Gas storage system is investigated, including as main components a high-temperature electrolyzer for hydrogen generation and a Sabatier reactor for methane production. The high-temperature Solide Oxide Electrolyser Cell (SOEC) technology, currently under development, is considered as a promising solution for hydrogen generation, due to the expected higher efficiency values, in comparison with conventional low-temperature electrolysis technologies. In order to evaluate the performance of the system and the energy efficiency, in this study a numerical model of the SOEC integrated with the Sabatier reactor has been implemented, including also the necessary additional auxiliaries, which can significantly affect the energy conversion performance. The whole energy conversion and storage system has been analyzed, taking into account different layout variants, by means of Aspen HysysTM numerical tool, based on a lumped modelling approach. The various Power-to-Gas storage configurations have been compared, with the aim to optimize both the system's efficiency and the composition of the produced gas stream

IDENTIFICATION AND ASSESSMENT OF INDICATORS AFFECTING ENERGY LOSS IN THE ELECTRIC DISTRIBUTION NETWORKS CASE STUDY: ASSALUYEH, BUSHEHR AND DEYLAM

Abstract. Due to its widespread applications, electrical energy has always been of great importance so that a power outage even for a moment may cause many irreparable problems. Power outage or shortage may occur for different reasons including the loss of energy in the electric distribution network. Loss of energy will impose enormous costs to the government. In this regard, the aim of this study is to identify the factors causing the loss of energy in the electricity distribution networks. By further understanding of these factors, their impact on the distribution networks can be largely reduced. The lack of knowledge on the regions with high loss of energy and the importance of each indicator in a particular area will result in more energy loss by diverting the decisions of managers and decision-makers from the main goal. Twelve experts from the electricity industry participated in this study. The comments by the experts were collected using a questionnaire. Using the theoretical background and the Likert scale, the parameters affecting the energy loss in the distribution networks were identification. These indicators include energy theft, measurement errors, load, network aging, loose connections, improper placement of equipment, voltage, resistance of the conductor, losses from equipment, the location and size of capacitors, geographical conditions, size and dimensions of the conductor, current leakage and network configuration. Using the Cardinal weights, the indicators were weighted and ranked in Assaluyeh, Bushehr and Deylam in Bushehr province. The most important factors affecting energy loss in Assaluyeh, Bushehr and Deylam include energy theft, the location and size of the capacitors and network configuration, respectively.Keywords: loss of energy, Cardinal weights, electricity distribution network

UPQC Implements The 3-Phase Shunt And Series Active Power Filter To Compensate Current And Voltage Harmonics

This paper presents the three phase shunt and series active power filter in order to reduce the current and voltage harmonics. To implement Unified Power Quality Conditioner (UPQC) control algorithm two control strategies p-q instantaneous power and d-q synchronous frame theory are used to mitigate the problems of power quality caused due to nonlinear loads. Both control theories performances are carried out and compared under nonlinear loads. The performance of UPQC with two control strategies has been tested in the Matlab/Simulink environment. The simulation results showed better performance for harmonic problem

Expansion planning of power distribution systems considering reliability : a comprehensive review

One of the big concerns when planning the expansion of power distribution systems (PDS) is reliability. This is defined as the ability to continuously meet the load demand of consumers in terms of quantity and quality. In a scenario in which consumers increasingly demand high supply quality, including few interruptions and continuity, it becomes essential to consider reliability indices in models used to plan PDS. The inclusion of reliability in optimization models is a challenge, given the need to estimate failure rates for the network and devices. Such failure rates depend on the specific characteristics of a feeder. In this context, this paper discusses the main reliability indices, followed by a comprehensive survey of the methods and models used to solve the optimal expansion planning of PDS considering reliability criteria. Emphasis is also placed on comparing the main features and contributions of each article, aiming to provide a handy resource for researchers. The comparison includes the decision variables and reliability indices considered in each reviewed article, which can be used as a guide to applying the most suitable method according to the requisites of the system. In addition, each paper is classified according to the optimization method, objective type (single or multiobjective), and the number of stages. Finally, we discuss future research trends concerning the inclusion of reliability in PDS expansion planning

Planeamiento de expansión de los sistemas de distribución eléctrica mediante el uso de un algoritmo voraz

Una adecuada planificación de un sistema de distribución de energía eléctrica es crucial para garantizar que los consumidores serán provistos de una energía de calidad. A lo largo del siglo pasado y en comienzos del presente, la planificación de los sistemas de distribución se realizaba de forma rudimentaria, sin métodos de solución matemáticos. Paulatinamente la planeación de la expansión de sistemas de distribución usando métodos de optimización ha ofrecido resultados eficaces y confiables. Mediante el presente artículo se presenta una innovadora alternativa de expansión de sistemas de distribución mediante el uso de algoritmos de búsqueda local y solución aleatoria. El método aplicado ha generado resultados eficaces que han sido validados en un sistema de distribución de 54 nodos.An adequate planning of an electric power distribution system is crucial to ensure that consumers will be provided with quality energy. Throughout the last century and the beginning of the present one, distribution system planning was carried out in a rudimentary manner, without mathematical solution methods. Gradually, the planning of distribution system expansion using optimization methods has offered effective and reliable results. This article presents an innovative alternative for distribution system expansion through the use of local search algorithms and random solution. The applied method has generated effective results that have been validated in a 54-node distribution system.0000-0002-8803-681

Temporary Load Shedding - Optimization of power distribution system using load shedding Techniques

In today’s world, electrical energy is a necessity. The dependency on electricity is increasing day by day which caused the system to work under a stress state close to stability limits and disturbances. An efficient power system supplying electrical energy must be reliable, stable, secure, and reasonable to meet consumer needs. The power demand depends on several factors and weather is one of the main in them. The thesis is done with the cooperation of Arva As. for the Tromsøya region in northern Norway. In Northern Norway, during the winter season, the temperature falls to -20˚C which eventually causes the rise in demand for electricity to meet the heating needs. The heating of households plays a big role in increasing demand. To avoid contingency and keep the distribution grid stable during the winter season a temporary load shedding scheme has been proposed by using the load curves and grid model that was analyzed through power flow analysis. It includes procedures for detection of voltage stability on buses with voltage stability indexes and plans to temporarily shut the heating system and sources to avoid the stress on the grid in peak hours with available communication possibilities

Metaheuristic Optimization of Power and Energy Systems: Underlying Principles and Main Issues of the `Rush to Heuristics'

In the power and energy systems area, a progressive increase of literature contributions that contain applications of metaheuristic algorithms is occurring. In many cases, these applications are merely aimed at proposing the testing of an existing metaheuristic algorithm on a specific problem, claiming that the proposed method is better than other methods that are based on weak comparisons. This ‘rush to heuristics’ does not happen in the evolutionary computation domain, where the rules for setting up rigorous comparisons are stricter but are typical of the domains of application of the metaheuristics. This paper considers the applications to power and energy systems and aims at providing a comprehensive view of the main issues that concern the use of metaheuristics for global optimization problems. A set of underlying principles that characterize the metaheuristic algorithms is presented. The customization of metaheuristic algorithms to fit the constraints of specific problems is discussed. Some weaknesses and pitfalls that are found in literature contributions are identified, and specific guidelines are provided regarding how to prepare sound contributions on the application of metaheuristic algorithms to specific problems