Outdoor Insulation and Gas Insulated Switchgears

This book focuses on theoretical and practical developments in the performance of high-voltage transmission line against atmospheric pollution and icing. Modifications using suitable fillers are also pinpointed to improve silicone rubber insulation materials. Very fast transient overvoltage (VFTO) mitigation techniques, along with some suggestions for reliable partial discharge measurements under DC voltage stresses inside gas-insulated switchgears, are addressed. The application of an inductor-based filter for the protective performance of surge arresters against indirect lightning strikes is also discussed

Effect of water on electrical properties of Refined, Bleached, and Deodorized Palm Oil (RBDPO) as electrical insulating material

This paper describes the properties of refined, bleached, deodorized palm oil (RBDPO) as having the potential to be used as insulating liquid. There are several important properties such as electrical breakdown, dielectric dissipation factor, specific gravity, flash point, viscosity and pour point of RBDPO that was measured and compared to commercial mineral oil which is largely in current use as insulating liquid in power transformers. Experimental results of the electrical properties revealed that the average breakdown voltage of the RBDPO sample, without the addition of water at room temperature, is 13.368 kV. The result also revealed that due to effect of water, the breakdown voltage is lower than that of commercial mineral oil (Hyrax). However, the flash point and the pour point of RBDPO is very high compared to mineral oil thus giving it advantageous possibility to be used safely as insulating liquid. The results showed that RBDPO is greatly influenced by water, causing the breakdown voltage to decrease and the dissipation factor to increase; this is attributable to the high amounts of dissolved water

Time domain analysis of switching transient fields in high voltage substations

Switching operations of circuit breakers and disconnect switches generate transient currents propagating along the substation busbars. At the moment of switching, the busbars temporarily acts as antennae radiating transient electromagnetic fields within the substations. The radiated fields may interfere and disrupt normal operations of electronic equipment used within the substation for measurement, control and communication purposes. Hence there is the need to fully characterise the substation electromagnetic environment as early as the design stage of substation planning and operation to ensure safe operations of the electronic equipment. This paper deals with the computation of transient electromagnetic fields due to switching within a high voltage air-insulated substation (AIS) using the finite difference time domain (FDTD) metho

China’s 10-year progress in DC gas-insulated equipment: From basic research to industry perspective

The construction of the future energy structure of China under the 2050 carbon-neutral vision requires compact direct current (DC) gas-insulation equipment as important nodes and solutions to support electric power transmission and distribution of long-distance and large-capacity. This paper reviews China's 10-year progress in DC gas-insulated equipment. Important progresses in basic research and industry perspective are presented, with related scientific issues and technical bottlenecks being discussed. The progress in DC gas-insulated equipment worldwide (Europe, Japan, America) is also reported briefly

High Voltage Insulating Materials-Current State and Prospects

Studies on new solutions in the field of high-voltage insulating materials are presented in this book. Most of these works concern liquid insulation, especially biodegradable ester fluids; however, in a few cases, gaseous and solid insulation are also considered. Both fundamental research as well as research related to industrial applications are described. In addition, experimental techniques aimed at possibly finding new ways of analysing the experimental data are proposed to test dielectrics

CHARGE TRANSPORT AND ACCUMULATION AROUND HVDC INSULATORS

High voltage direct current (HVDC) based transmission of electric power, in comparison with high voltage alternating current (HVAC) transmission over a distance of over 800 km, has the advantages of higher transmission capability, lower line loss, more confined damage by fault, and that all AC lines connected to an HVDC system do not need to be synchronized. However, under DC conditions the electric field across the insulation space remains unidirectional and stable, which results in charge accumulation, leading to significant differences in the dielectric behavior and flashover characteristics of insulation materials in comparison with those under AC conditions. There exists limited amount of test data and research results on HVDC insulation behaviour. It is therefore necessary to carry out in-depth study of the discharge mechanisms and behavioral characteristics of the insulation materials required for HVDC transmission systems. The research in this thesis aims at the understanding of the charge transport and accumulation process inside and around insulators made of epoxy composite material. Firstly, the physical mechanisms are critically reviewed with appropriate experimental results selected for model verification. The model developed in the work encompasses all important mechanisms. Material properties obtained under different conditions are reviewed and values for the cases investigated in the present work determined. Charge transport is dominated by the drift of two types of oppositely charged particles in electric field with nonlinear generation source terms, giving rise to extreme difficulties for convergence of computation in strong electric field. As a result, special code is developed for a commercial software package (COMSOL based on finite element method) to implement the model and also the complicated boundary conditions. To gain confidence in the model and its implementation including the boundary conditions and material properties the model is verified in the work against experimental cases with different gas, geometry and applied voltage. An experimental study of the effect of surface charge accumulation on the potential distribution along the surface of an epoxy insulator under HVDC stress was carried out under non-ideal conditions

DEMSEE (2007: Istanbul)

It is true that Electricity is a pillar for our present Civilization and Culture. One should also recognize that Electricity is the finest useable form of Energy and therefore the most precious. Deregulation of Electricity Markets aims ultimately to make almost everyone responsible for the way electricity is generated, distributed and used. It aims to let fair market rules result in a Market Operation that will advance this sense of responsibility for everybody. This is particularly important in view of the present delicate state of the Environment which should for Humanity’s sake be preserved, at all costs. And indeed, we are lucky in the sense that the current Information Technologies and Information and Communication Technology will allow us to live up to our responsibilities concerning rational electricity usage as well as the preservation of the environment. However, a strong, wide and lasting commitment is necessary, i.e. political will by every nation, to achieve progress with respect of the environment. ...ELECTRIC POWER SUPPLY: THE ENGINEERING CHALLENGES AND THE CONTRIBUTION OF CIGRE / Jean KOWAL, 1 -- SUBSIDIES IN WHOLESALE ELECTRICITY MARKET / Osman SEVAİOĞLU, 8 -- GASEOUS DIELECTRICS IN POWER TRANSMISSION AND DISTRIBUTION / Loucas G. CHRISTOPHOROU, 13 -- INFRASTRUCTURE DEVELOPMENT AND POWER SYSTEM SECURITY ISSUES IN A LIBERALIZED ENVIRONMENT IN SOUTH-EASTERN EUROPE (SEE) -- Evangelos LEKATSAS, 20 / NATURAL HAZARDS, GLOBAL CLIMATE CHANGE AND ENERGY PRODUCTION -- Menas KAFATOS, 27 / EDUCATIONAL EXPERIMENT KIT STUDIES ON RENEWABLE ENERGY SOURCES -- Özcan ATLAM, 32 / AN EFFECTIVE SET OF I.C.T. TOOLS FOR TEACHING & LEARNING OF RENEWABLE ENERGY SYSTEMS (RES) -- S. KAPLANIS, E. KAPLANI, 41 / A GIS WEB – APPLICATION FOR POWER SYSTEM OF CRETE -- J. SYLLIGNAKIS, C. ADAMAKIS, T.M. PAPAZOGLOU, 48 / DIAGNOSTIC REVIEW OF A BLACKOUT IN RHODES -- T. M. PAPAZOGLOU, E.J. THALASSINAKIS, C. TSICHLAKIS, N.D. HATZIARGYRIOU, 55 / REAL-TIME TRANSFORMER DYNAMIC LOADING APPLICATION-IMPLEMENTATION AND PRACTICAL USE -- S. KRSTONIJEVIĆ, N. ČUKALEVSKI, G. JAKUPOVIĆ, N. DAMJANOVIĆ, S. CVETIĆANIN, 62 / A COMPARISON OF THE PERFORMANCE RATIO OF PHOTOVOLTAIC MODULES AT DIFFERENT TILT ANGLES -- E. DRAKAKIS, F. MAVROMATAKIS, Y. RANGHIADAKIS, P. TZANETAKIS and I. FRAGIADAKIS, 69 / ON THE MAXIMIZATION OF THE COST-EFFECTIVENESS OF A PV PLANT -- S. KAPLANIS, E. KAPLANI, 75 / INTEGRATED SOFTWARE, FOR IMPULSE VOLTAGES ESTIMATION, IN HIGH VOLTAGE NETWORKS WITH DISTRIBUTED GENERATION -- Stavros LAZAROU, Eleftheria PYRGIOTI, Dimosthenes AGORIS, 83 / NEW 400 kV INTERCONECTION OHL KOSOVO - ALBANIA AND TRANSMISSION NETWORK CONCEPT OF KOSOVO -- S. LIMARI1, K. BAKIC, K. ROBO, L. AHMA, 92 / DEREGULATED ELECTRICITY MARKET IN SOUTH – EASTERN EUROPE: ACTIVE NETWORKS -- Venizelos EFTHYMIOU, 102 / CO2 EMISSIONS FROM THE USE OF FOSSIL FUELS IN CRETE – GREECE -- John VOURDOUBAS, Antonios PITARIDAKIS, Charalampos LITOS, 109 / SURVEY OF POWER EXCHANGES – ORGANIZATION AND RESPONSIBILITIES -- O. GJERDE, O.B. FOSSO, 1J. BOGAS, 114 / FREQUENCY PERFORMANCE MONITORING AND ANALYSIS IT SUBSYSTEM FOR a TSO’s CONTROL CENTRE: ARCHITECTURE AND INITIAL EXPERIENCE WITH ITS USE -- Goran JAKUPOVIĆ, Ninel ČUKALEVSKI, Nikola OBRADOVIĆ, 121 / MARIN POLLUTION AND EFFECTIVE USE OF THE RTV SILICON COATINGS IN CRETAN POWER SYSTEM -- Emmanuel J. THALASSINAKIS, 128 / MONTE CARLO PROCEDURES FOR SIMULATING REAL TIME CONTINGENCES AND SETTING OPTIMAL REDISPATCHING STRATEGIES IN MULTI-AREA SYSTEMS -- S. BENINI, A. LEONI, P. PELACCHI, D. POLI, 136 / COMPARING DIFFERENT APPROACHES TO SOLVE THE UNIT COMMITMENT PROBLEM CONSIDERING HYDRO-PUMPED STORAGE STATIONS -- Yiannis A. KATSIGIANNIS, Emmanuel S. KARAPIDAKIS, 147 / ROOF INTEGRATED SOLAR PARABOLIC COLLECTORS SIMULATION ANALYSIS -- G. BARAKOS, S. KAPLANIS, M. PETRAKIS, A. SPYROGIANNOULAS, 154 / THE ROLE OF A POWER EXCHANGE FOR ENERGY TRADING AND POWER GENERATION INVESTMENT -- Bakatjan SANDALKHAN, 161 / HEURISTIC BASED SYNCHRONOUS GENERATOR EXCITATION CONTROL FOR USE IN A DEREGULATED ENVIRONMENT OF ISLAND POWER SYSTEMS -- Yannis L. KARNAVAS, Nicolaos P. POLYZOS, 169 / INNOVATIVE EDUCATION, TRAINING AND DEVELOPMENT PRACTICES AT THE ELECTRICITY AUTHORITY OF CYPRUS -- George ASHIKALIS, 177 / WIND FARMS EXPERIENCE IN CRETE ISLAND -- Antiopi GIGANTIDOU, Ioannis STEFANAKIS, N.D. HATZIARGYRIOU, 186 / PUBLIC KEY INFRASTRUCTURE AS A NEW TECHNOLOGY ENABLING ELECTRONIC AUCTIONS USED IN THE CONTEXT OF ELECTRICITY MARKET RESTRUCTURING: AN ASPECT OF THE COMPLEX GLOBAL ECONOMY -- John K. SAKELLARIS, 195 / THE LIBERALIZATION OF THE ELECTRIC POWER MARKET IN SOUTH – EASTERN MEDITERRANEAN -- Dimitris SARRIS, 202 / DETERMINATION OF COST STAGES OF TRANSMISSION LINE PRODUCTS FROM LONDON METAL EXCHANGE TO FINAL CONSUMER -- Sedat KARABAY, Ahmet ŞEN, 205 / NON-INTRUSIVE, ON-LINE RESIDENTAL METERING BASED ON BROADBAND COMMUNICATION -- Ali İNAN, Themis PAPASTERGIOU, 213 / CONTRIBUTION OF LANDFILL GAS ELECTRICITY GENERATION TO ENERGY BALANCE OF CRETE ISLAND: AN ECONOMIC, ENVIRONMENTAL AND SUSTAINABLE ASSESSMENT USING LEAP MODEL -- A. A. TSAVE, E. S. KARAPIDAKIS, P. M. SOUPIOS, 2181st ed

The Extension of the RAINS Model to Greenhouse Gases

Many of the traditional air pollutants and greenhouse gases have common sources, offering a cost-effective potential for simultaneous improvements for both traditional air pollution problems as well as climate change. A methodology has been developed to extend the RAINS integrated assessment model to explore synergies and trade-offs between the control of greenhouse gases and air pollution. With this extension, the RAINS model allows now the assessment of emission control costs for the six greenhouse gases covered under the Kyoto Protocol (CO2, CH4, N2O and the three F-gases) together with the emissions of air pollutants SO2, NOX, VOC, NH3 AND PM. In the first phase of the study, emissions, costs and control potentials for the six greenhouse gases covered in the Kyoto Protocol have been estimated and implemented in the RAINS model. Emission estimates are based on methodologies and emission factors proposed by the IPCC emission reporting guidelines. The large number of control options for greenhouse gases have been grouped into approximately 150 packages of measures and implemented in the RAINS model for the European countries. These control options span a wide range of cost-effectiveness. There a re certain advanced technical measures with moderate costs, and certain measures exist for which the economic assessment suggests even negative costs, if major side impacts (cost savings) are calculated. Illustrative example calculations clearly demonstrate that conclusions on the cost-effectiveness of emission reduction strategies are crucially depending on the boundaries of the analysis. The net cost of greenhouse gas control strategies are significantly lower if the immediate cost-savings from avoided air pollution control costs are taken into consideration. For a 15 percent reduction of the CO2 emissions from the power sector in the EU, avoided pollution control costs could compensate two third of the CO2 control costs. Depending on the design of the control strategy, net costs of greenhouse gas mitigation could even be negative, which is in stark contrast to conclusions for a CO2 only strategy. However, there are certain greenhouse gas mitigation measures, such as increased use of biomass that could deteriorate the negative impacts of air pollution, while yielding very little economic synergies. A combined approach towards greenhouse gas mitigation and air pollution control would not only reveal economic synergies, but also harness additional environmental benefits. Even in a situation with stringent emission control requirements for air pollution as it is required by the EU legislation, modifications in fuel use geared towards reductions of greenhouse gases could lead as a side impact to significant reductions in the residual emissions of air pollutants. The economic benefits of such "windfall emission reductions" could be substantial. The extended RAINS model framework will offer a tool to systematically investigate such economic and environmental synergies between greenhouse gas mitigation and air pollution control while avoiding negative side impacts

Modern Telemetry

Telemetry is based on knowledge of various disciplines like Electronics, Measurement, Control and Communication along with their combination. This fact leads to a need of studying and understanding of these principles before the usage of Telemetry on selected problem solving. Spending time is however many times returned in form of obtained data or knowledge which telemetry system can provide. Usage of telemetry can be found in many areas from military through biomedical to real medical applications. Modern way to create a wireless sensors remotely connected to central system with artificial intelligence provide many new, sometimes unusual ways to get a knowledge about remote objects behaviour. This book is intended to present some new up to date accesses to telemetry problems solving by use of new sensors conceptions, new wireless transfer or communication techniques, data collection or processing techniques as well as several real use case scenarios describing model examples. Most of book chapters deals with many real cases of telemetry issues which can be used as a cookbooks for your own telemetry related problems

Voltage uprating of existing high voltage substations when transient voltage stress and available withstand strength are coordinated

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering in the High Voltage Research Group School of Electrical and Information Engineering Johannesburg, June 2017 South AfricaServitude availability in space-constrained built-up areas within the Johannesburg or Central Load Network (CLN) poses every-day challenges for power system engineers. Strengthening the backbone 88/275 kV transmission system within the CLN becomes even more difficult when multi-circuit transmission lines are required for increased power transfer capabilities. When uprating is considered to increase the power transfer capability, the withstand levels of existing external insulation demands an optimisation to find a new stress versus strength balance that allows reliable operation of substations at higher voltages. The research includes primarily an investigative simulation study to evaluate the current Eskom available design clearances in terms of their withstand capability when subjected to over-voltage transients. Two voltage range classes were evaluated and the results are discussed. For voltage range 1, it was found that the over-voltage stress was low enough to allow for a higher nominal operating voltage while maintaining the existing clearances. For voltage range 2, existing clearances are also found to be conservative and smaller safety margins will most likely be acceptable. From a transient analysis evaluation, voltage uprating is considered as a very attractive option to increase the power transfer capability of existing substations. Current Eskom clearances for 88 kV and 275 kV are expected to perform well during transients generated in uprated systems. Electrode grading to improve the field gradients in the substation will require attention to increase gap factors. Additional surge arresters are considered to be a cost effective solution to control over-voltages throughout the whole uprated substation. The physical modification of substations to replace strung conductors with tubular conductors, ensuring sufficient outage time to refurbish and rebuild with new equipment will be the most challenging part of uprating existing substations.MT 201