On-line monitoring of metal-oxide surge arresters using improved equivalent model with evolutionary optimisation algorithm

Abstract: A resistive-current extraction algorithm to assist with on-line monitoring of surge arresters is proposed in this paper. The algorithm is based on the improved equivalent model for surge arresters and combines evolutionary optimisation with the base-frequency approximating method. A genetic algorithm is used to obtain the optimal capacitance such that the phase shift between the base-components of the branch voltage and current is minimised thereby yielding a good approximation of the resistive current. In this paper, the algorithm is implemented and tested using Matlab/Simulink. Results indicate that the proposed algorithm is able to efficiently and accurately obtain the resistive component of the leakage current, using the improved equivalent model, under both ideal and distorted supply conditions

Electricity distribution networks’ analysis with particular references to distributed generation and protection

Electric power systems have served well the consumers need for continuous, uninterrupted power supply of good quality and at the minimum possible cost. However, nowadays, the worldwide increasing demand on electric power, coupled with governmental policy changes towards “green” energy and emissions reduction have led to significant changes in the electric power generation. These changes have introduced many serious issues and problems to the electric power systems and although they have been efficiently addressed in the past years, now they need to be restudied and reanalysed taking into consideration all new developments. Distributed generation (DG), constitutes one of the most important developments in modern electric power systems and introduced many benefits as well as drawbacks. DG units are connected to the electric power system near load centres, thus, directly to the distribution network. DG units are larger in number than the more massive conventional power stations and are linked to the introduction of bidirectional power flow. As a result, the configuration of the traditional electric power systems and the networks’ operation have been prominently altered over the last years as soon as DG was introduced into the electric network. This progress has offered many challenges that need to be addressed such as those in terms of control and protection of electric power systems and particularly of distribution networks. The current PhD Thesis attempts to offer a contribution to the electricity distribution networks’ studies with particular reference to distributed generation and protection. In particular, the problems and the issues arising from the installation of DG units in distribution networks are studied. Research on the methods for improving voltage profiles and for reducing real and reactive power losses in distribution networks caused by DGs installation is conducted. Moreover, a decision making algorithm is developed and proposed for selecting the optimum size and location of DG in distribution networks. Furthermore, a new technique based on syntactic pattern recognition for the identification of power system signals used by protective relays is developed in an effort to contribute in the deterrence and reduction of faults. Finally, extensive studies in a distribution network have been conducted, with and without DGs, which aimed to identify the influence of several important parameters in the network’s lightning performance and with its main goal the limitation of lightning faults

7th EEEIC International Workshop on Environment and Electrical Engineering : Wroclaw - Cottbus, 5 - 11. May 2008

The proposed solution meets the latest trends in world power engineering and has the lowest ecological costs amongst the accessible power engineering solutions. It is also in accordance with the Polish power engineering law, which takes into account the recommendations of the European Economic Commission, the Second Sulphur Protocol and the Framework Convention of the United Nations (concerning the changes of climate)

A Comprehensive Survey on Particle Swarm Optimization Algorithm and Its Applications

Particle swarm optimization (PSO) is a heuristic global optimization method, proposed originally by Kennedy and Eberhart in 1995. It is now one of the most commonly used optimization techniques. This survey presented a comprehensive investigation of PSO. On one hand, we provided advances with PSO, including its modifications (including quantum-behaved PSO, bare-bones PSO, chaotic PSO, and fuzzy PSO), population topology (as fully connected, von Neumann, ring, star, random, etc.), hybridization (with genetic algorithm, simulated annealing, Tabu search, artificial immune system, ant colony algorithm, artificial bee colony, differential evolution, harmonic search, and biogeography-based optimization), extensions (to multiobjective, constrained, discrete, and binary optimization), theoretical analysis (parameter selection and tuning, and convergence analysis), and parallel implementation (in multicore, multiprocessor, GPU, and cloud computing forms). On the other hand, we offered a survey on applications of PSO to the following eight fields: electrical and electronic engineering, automation control systems, communication theory, operations research, mechanical engineering, fuel and energy, medicine, chemistry, and biology. It is hoped that this survey would be beneficial for the researchers studying PSO algorithms

Intelligent Systems

This book is dedicated to intelligent systems of broad-spectrum application, such as personal and social biosafety or use of intelligent sensory micro-nanosystems such as "e-nose", "e-tongue" and "e-eye". In addition to that, effective acquiring information, knowledge management and improved knowledge transfer in any media, as well as modeling its information content using meta-and hyper heuristics and semantic reasoning all benefit from the systems covered in this book. Intelligent systems can also be applied in education and generating the intelligent distributed eLearning architecture, as well as in a large number of technical fields, such as industrial design, manufacturing and utilization, e.g., in precision agriculture, cartography, electric power distribution systems, intelligent building management systems, drilling operations etc. Furthermore, decision making using fuzzy logic models, computational recognition of comprehension uncertainty and the joint synthesis of goals and means of intelligent behavior biosystems, as well as diagnostic and human support in the healthcare environment have also been made easier

A bibliographic analysis of transformer literature 1990-2000

This paper presents an analysis of the bibliography on transformers covering the period from 1990 to 2000. It contains all the transformer subjects: a) Transformer design, b) Transformer protection, c) Transformer connections, d) Transformer diagnostics, e) Transformer failures, f) Transient analysis of transformers (overvoltages, overcurrents), g) Modeling and analysis of transformer using FEM (thermal modeling, losses modeling, insulation modeling, windings modeling). Several international journals were investigated including the following: Advances in Electrical and Computer Engineering, Canadian Journal of Electrical and Computer Engineering, COMPEL (The International Journal for Computation and Mathematics in Electrical and Electronic Engineering), Electrical Engineering, Electric Power Components and Systems, Electric Power Systems Research, European Transactions on Electrical Power, IEEE Transactions on Magnetics, IEEE Transactions on Power Delivery, International Journal of Electrical Power and Energy Systems, and IET Generation Transmission & Distribution. Due to the high number of publication in journals, we are not considering publications of conferences and symposia. A total of 700 publications are analyzed in this paper. The research presented in this paper is important because it contains and analyzes the best research papers on transformers coming from many countries all over the world and published in top rated scientific electrical engineering journals

WOFEX 2021 : 19th annual workshop, Ostrava, 1th September 2021 : proceedings of papers

The workshop WOFEX 2021 (PhD workshop of Faculty of Electrical Engineer-ing and Computer Science) was held on September 1st September 2021 at the VSB – Technical University of Ostrava. The workshop offers an opportunity for students to meet and share their research experiences, to discover commonalities in research and studentship, and to foster a collaborative environment for joint problem solving. PhD students are encouraged to attend in order to ensure a broad, unconfined discussion. In that view, this workshop is intended for students and researchers of this faculty offering opportunities to meet new colleagues.Ostrav

Aeronautical engineering, a continuing bibliography with indexes

This bibliography lists 823 reports, articles, and other documents introduced into the NASA scientific and technical information system in November 1984