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Highlights: [•] We model direct drive permanent magnet linear generators for wave energy converters. [•] We review the magnetic forces and the electrical output power. [•] We suggest new optimised design for direct drive linear generator. [•] The optimisation aims reduction of forces parallel and normal to axis of motion. [•] The optimisation aims increase of the electrical power output. [ABSTRACT FROM AUTHOR]

The problem of harmonic reduction is alternatively approached as an energy user’s problem. The user’s objective is to eliminate his voltage harmonic distortion problem locally without considering the effects of voltage distortion at neighboring buses. The remedy is insertion of a reactor in series with the local compensating capacitor. A method is presented for finding the optimum fixed LC combination to minimize voltage harmonic distortion at a load bus while holding the power factor at a desired value and constraining the compensator values which would create resonant conditions and the manufacturer’s standard values for power shunt capacitors. [Copyright &y& Elsevier]

• Overhead transmission lines can be improved by using ampacity and DSM techniques. • MonteCarlo sampling can provided near-optimal solutions in Demand-Side Management. • Loads in factories can be aggregated according their criticity and time dependency. • Factories can increase their power without investing in new supply infraestructures. An electric arc-furnace is a complex industry which demands high levels of electrical energy in order to heat iron materials and other additives needed for the production of cast iron and/or steelmaking. The cost of the electrical energy demanded by the factory during the production can be greater than 20% of the overall cost. This kind of arc-furnace allows the production of steel with levels of scrap metal feedstock up to 100%. From an electrical point of view, the factory size in terms of its maximum apparent power demanded from the grid is designed to make use of the static capacity of the transmission line that supplies the energy. In that case, it is not possible to increase the power of the factory above the static rating by adding new facilites without installing new transmission infrastructures. This paper presents a methodology that allows an increase in net power of an arc-furnace factory without installing new transmission lines. The novelty of the proposed solution is based on a mix strategy that combines Demand-Side Management (DSM) methodologies and the use of ampacity techniques according IEEE 738 and CIGRE TB601. The application of DSM methodologies provides an improvement in the sustainability of not only the industrial customer but also in the overall grid. As a secondary effect, it reduces operational costs and the greenhouse gas emissions. The proposed methodology has been tested in an arc-furnace factory located in the North of Spain. [ABSTRACT FROM AUTHOR]

Highlights • The most relevant enabling methodologies for Smart Grids computing, monitoring and control have been analyzed and discussed. • Conceptualization of decentralized, self-organizing, proactive, and holistic computing paradigms aimed at supporting rapid decision in a data-rich, but information-limited environment represents a very promising research activity. • Many important smart grid applications could be benefited from the deployment of these information services. Abstract The deployment of traditional computing, control and monitoring paradigms in modern smart grids is characterized by several severe limitations. These could restrict their capability to manage the huge complexities and the vast penetration of distributed and renewable energy resources that are expected in future operational scenarios. In this context, the design of more scalable and more flexible solution paradigms represents a relevant issue to address. The enabling technologies and methodologies aimed at addressing these complex challenges include decentralized computing, self-organizing sensor networks, proactive control, and holistic computing frameworks. Accordingly, in this paper a selection from literature published on these topics will be analyzed and reviewed, in order to outline the most relevant research trends, and the main open problems. [ABSTRACT FROM AUTHOR]

Optimization criteria are presented which allows proper calculation of optimal power factor. Optimization minimizes the line loss, maximizes the power factor and maximizes the efficiency taking into consideration the skin effect. The performance of the obtained capacitor is discussed by means of numerical example. [Copyright &y& Elsevier]

The effect of capacitance compensation of non-linear loads is considered on the displacement factor (DIPF), distortion factor (DISF), and power factor. Optimization of the DIPF is found to result in reduction of the DISF to a minimum value. [Copyright &y& Elsevier]