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The current paper resumes the design of a steel lattice transmission tower carried out in the framework of the RFCS‐funded research project ANGELHY. The scope of ANGELHY is the establishment of analysis methods for lattice towers and the development of design rules for steel and hybrid angle sections, as well as built‐up members composed of angles. In Europe, the design of transmission towers for overhead electrical lines can be carried out according to EN 1993‐3‐1: 2006 or for electrical lines exceeding 1 kV according to EN 50341‐1: 2012. Both standards prescribe linear elastic global analyses for the design of steel lattice towers. In the current paper, the linear elastic design of the suspension transmission tower according to the German National Annex of EN 50341‐1:2012 is presented. In a first step, common typologies of lattice transmission towers used in Europe are described. In a second step, the chosen tower typology is explained in detail. The Danube tower represents the widest spread tower typology in Europe. Finally, the detailed design procedure of the tower according to EN 50341‐1:2012 is presented. The design is carried out with the software TOWER – Version 15.0 from Power Line Systems. [ABSTRACT FROM AUTHOR]

In this paper, we present a two-stage model of zonal electricity markets with day-ahead market clearing, and real-time re-dispatch and balancing that accounts for transmission line switching at both stages. We show how the day-ahead problem with switching can be formulated as an adaptive robust optimization problem with mixed integer recourse, and present a new algorithm for solving the adversarial max-min problem that obeys the structure of an interdiction game. We apply the model on a realistic instance of the Central Western European system, and comment on the impacts of both proactive, and reactive transmission switching on the operating costs of the system. Part I presents day-ahead models of a short-term zonal electricity market with switching, and describes our algorithmic approach for solving these models efficiently. Part II describes variants of the real-time model, and presents the results of our case study on the Central Western European market. [ABSTRACT FROM AUTHOR]

This paper presents a review of the high altitude EMP (HEMP) activities in European countries between 1970 and 1995. HEMP simulators built in different countries are presented together with measurements performed under them and calculation methods developed in order to simulate the currents or voltages induced by an HEMP in power or telecommunication lines or in other types of circuits. Comparison between calculations and measurements are shown. This paper focuses on this period, which was of historical importance for the hardening of vital military and governmental installations, but which permitted also the development and validation of models to study the electromagnetic effects of lightning. [ABSTRACT FROM AUTHOR]

The first of this two-paper series addresses a practical day-ahead auction model, where generation revenue constraints are explicitly incorporated in the problem formulation, as routinely done in several national electricity markets across Europe. The revenue-constrained market-clearing procedure includes the effect of the transmission network, inter-temporal constraints associated with generation scheduling, demand-side bidding, and marginal pricing. This auction design is an instance of price-based market clearing which features two major complicating factors. First, locational marginal prices become decision variables of the optimization process. In addition, producer revenues are formulated as bilinear and highly nonconvex products of power outputs and market-clearing prices. The resulting problem is formulated as a mixed-integer nonlinear bilevel program with bilinear terms for which available solution techniques rely on heuristics, approximations, or modeling simplifications. This paper presents a novel and exact methodology whereby the original problem is recast as an equivalent single-level mixed-integer linear program. As a consequence, finite convergence to optimality is guaranteed and the use of standard commercial software is allowed. The proposed transformation is based on duality theory of linear programming, Karush-Kuhn-Tucker optimality conditions, and integer algebra results. In the second part of this two-paper series, numerical results from several case studies illustrate the effective performance of the proposed solution approach. [ABSTRACT FROM AUTHOR]

Exceeding the electric field's limit value is not allowed in the vicinity of high-voltage power lines because of both legal and safety aspects. The design parameters of the line must be chosen so that such cases do not occur. However, analysis of several operating power lines in Europe found that the electric field strength in many cases exceeds the legally prescribed limit for the general public. To illustrate this issue and its importance, field measurement and finite element simulation results of the low-frequency electric field are presented for an active 400 kV power line. The purpose of this paper is to offer a new, economical expert system based on dynamic line rating (DLR) that utilizes the potential of real-time power line monitoring methods. The article describes the expert system's strengths and benefits from both technical and financial points of view, highlighting DLR's potential for application. With our proposed expert system, it is possible to increase a power line's safety and security by ensuring that the electric field does not exceed its limit value. In this way, the authors demonstrate that DLR has other potential applications in addition to its capacity-increasing effect in the high voltage grid. [ABSTRACT FROM AUTHOR]

During the last decades the production of electrical energy has been liberalized. This paper studies the effect of using a market mechanism to allocate scarce transmission capacity when the incumbent producers remain dominant. We show that granting exclusive use to an incumbent producer is preferred to trading access to this essential facility if interregional production-cost differences are significant and transmission capacity is scarce. This result counters the intuition on third degree price-discrimination, that arbitrage will improve the social surplus when there is no output contraction. The reason is that with arbitrage the incumbent can still charge different regional prices as long as it creates congestion on the transmission lines. As a consequence, welfare will be lower, since the incumbent distorts production decisions to congest the lines. We recommend that a market-oriented access to scarce transmission capacity should be accompanied by additional regulatory or structural measures to address market power. [ABSTRACT FROM AUTHOR]

This paper presents a solution for transmission of bulk power over long distances. It allows the interconnection between remote power plants and power grids, which is a common situation in countries with continental dimensions, such as China, Russia, Brazil, and Canada, and also special projects like supergrids in Europe and Asia. This paper also presents an analytical analysis of series and shunt FACTS applications for tapping and power flow control in half-wavelength transmission lines. The proposed FACTS devices are able to drain or inject fractional active power in the half-wavelength line and simultaneously to control the main power flow through the line by means of reactive power compensation, without mischaracterizing its particular principle of half-wavelength operation. Simulation results from a frequency-dependent model of transmission line and the complete models of the series and the shunt FACTS devices were obtained in the PSCAD/EMTDC to demonstrate the feasibility of the proposed systems. [ABSTRACT FROM PUBLISHER]

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Abstract: The European Network of Transmission System Operators for Electricity has been publishing network reliability data for major fault events in the European electricity transmission network since 2002. The work presented focuses on three reliability indicators provided for each major fault event: energy not supplied, total loss of power and restoration time. The purpose of this paper is to assess the usefulness of these indicators and to gain a better understanding of the impact of network topology on transmission network reliability. The topology is assessed in terms of network interconnectivity. For each indicator, the sum of the observed values and the Empirical Cumulative Distribution Functions (ECDF) are used to compare networks with different topologies. More interconnected grids have experienced a larger number of fault events. However, their impacts in terms of reliability indicators are significantly lower. In spite of the observed differences between network groups, results show significant sensitivity to reliability indicators’ data sets. The usefulness and significance of transmission network reliability indicators are discussed. [Copyright &y& Elsevier]

The adoption of the European Union's target to increase the share of energy from renewable sources to 20 % requires a substantial modernisation and rebuilding of the electricity grid. Current grid projects are often delayed for a variety of reasons, such as the inefficiency of permitting procedures or local opposition. In fall 2011, the European Commission proposed a regulation which aims at enhancing the necessary grid expansion. The legislation was adopted by the European Parliament and the Council in April and came into force on 15 May 2013. Among other considerations, the legislation aims at tackling the aforementioned challenges by making permitting procedures more efficient and implementing measures to increase the acceptance of new power-lines. However, questions remain about the quality and quantity of the proposed provisions designed to overcome all details of the identified problems. It will depend on the implementation of this legislation both on the European and on local level whether the new provisions will prove to be successful in terms of increased procedure efficiency and decreased public opposition. EU institutions, national governments, and competent public authorities should be aware of the area of conflict between improved procedure efficiency and increased public acceptance. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to provide life cycle inventory data and results for components of electrical grids to the larger community of life cycle assessment practitioners. This article is the first in a series of two, each focusing on different components of power grids. In part 1, the objects under scope are power lines and cables. Systems for overhead, underground, and subsea transmission are modeled here, including HVDC systems used in long-distance transmission. Methods: We use process-based life cycle assessment based on information provided by companies and in reports, Ecoinvent v2.2 as a background dataset and ReCiPe Midpoint Hierarchist perspective v1.0 as the impact assessment method. The average European power mix is used to model the electrical energy required to compensate power losses in the equipment. Results and discussion: Under the assumption of European power mix, power losses are the dominant process for impacts of lines and cables in all impact categories, contributing with up to 99% to climate change impacts. An exception is the category of metal depletion, for which the production of metal parts is the most relevant process. Conclusions: After power losses, processes generating the most impacts for overhead lines are the production of metals for masts and conductors; production of foundations comes third. Recycling of metal parts shows benefits in all impact categories. For cables, infrastructure impacts are dominated by cable production, and recycling of cable materials does not always compensate for the other impacts generated at the end of life. [ABSTRACT FROM AUTHOR]

Power system vulnerability is a key concern in modern societies and many efforts have been devoted to its analysis. Recently, the wide domain of complex networks that can be used to assess the vulnerability of network systems has been applied to power grids as well with focus on the topological vulnerability of the transmission systems based on its structure in terms of the nodes and their connection patterns. However, a pure topological approach, as proposed in the current literature, fails in capturing the specific features of power systems. The authors propose an extended topological approach, which can incorporate several important features of the power grids such as flow paths, line flow limits and gen/load bus distribution. Also, a set of new metrics able to provide an assessment of the system vulnerability is defined. ‘Net-ability’ measures the aptitude of the grid in transmitting power from generation to load buses efficiently. ‘Path redundancy’ assesses the available redundancy in terms of paths in transmitting power from a generation to a load bus based on entropy. Based on the previous two metrics, the authors introduce a third metric, the ‘survivability’, as a global metric to evaluate the aptitude of the network in assuring the possibility to match generation and demand in case of failures or attacks. The metrics proposed will be applied to different test systems and to a real-transmission system to illustrate their application and effectiveness. [ABSTRACT FROM AUTHOR]

Examines the impact of different transmission link radiation and the localized defect contribution in Europe. Use of theoretical method based on the finite-difference time domain algorithm; Influence of geometry and global link configuration on radiation mechanism; Efficiency of transient analysis for the prediction of radiation losses.