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[en] Bell Canada and Hydro-Quebec have developed a joint program on internal environmental assessments (IEA) of the distribution system. The program was designed to cover all distribution line modernization and construction projects. The implementation of the IEA was carried out in three phases: (1) tool development including training needs, (2) a pilot project, and (3) full implementation throughout the distribution system. The general IEA method and the 'General Guide on IEA' were described in detail. Impact categories, grids and job aids and a follow-up guide, and environmental training programs were described from the first phase of development. The pilot project of phase 2 was used to evaluate the procedure. Projects were evaluated by environmental specialists for relevance of carrying out an environmental assessment. Useful elements and difficulties with the process were also scrutinized. The complete process was to be applied to over 25,000 distribution system elements per year. 2 refs
[en] A 1996 European directive put an end on power production and dispatching monopolies in Europe. The distribution grids became essential structures opened to all power producers and suppliers in exchange for the payment of a fee set by an independent regulatory commission. These grids and networks that are strongly interconnected at the European scale have to play with the specificities of each country. For instance the French power demand is strongly correlated with the temperature as most buildings relies on electricity for heating. Another specificity is that each country is free to choose its energy mix and its production means so German mix relies mainly on coal and lignite while France chose nuclear power. Today's grids are challenged because they have to absorb a growing part of renewable energies and they face also the development of auto-consumption. The solution that is looming is the coexistence of large interconnected European grids with small networks whose meshing is at the district scale to satisfy collective production and auto-consumption. (A.C.)
[en] We have proposed a 3 phase, 100 MVA, 154 kV class HTS transformer substituting for a 60 MVA conventional transformer. The power transformer of 154 kV class has a tertiary winding besides primary and secondary windings. So the HTS transformer should have the 3rd superconducting winding. In this paper, we designed conceptually the structure of the superconducting windings of a single phase 33 MVA transformer. The electrical characteristics of the HTS transformer such as % impedance and AC loss vary with the arrangement of the windings and gaps between windings. We analyzed the effects of the winding parameters, evaluated the cost of each design, and proposed a suitable HTS transformer model for future power distribution system.
[en] It would be easy to attribute the collapse of the futures market in California electricity to the alleged manipulations of over-the-counter traders. This paper provides evidence to the contrary. Findings reveal an active market that lost the speculative and small investor interest, leaving hedgers to face hedgers in a volatile and less active arena. Hedge ratio analysis shows an erratic price-matching ability that many times suggested a long hedge when a short would be expected. Overall, contract failure could be attributed to inaccurate hedging opportunities and lack of speculative interest to keep the market going during lulls in hedging demand
[en] The power distribution systems considered for the ATLAS Inner Tracker Upgrade include linear voltage regulators on the front-end chips. In the paper we present two designs: a classical voltage regulator based on an NMOS transistor as the pass element, and an LDO voltage regulator employing a PMOS device. Both prototype regulators have been implemented in the 130 nm CMOS process and are foreseen to be integrated in the ABC130 front-end chip. In the paper the designs as well as the pre- and post-radiation test results for both prototypes are presented and discussed.
[en] The reliability of power supply is no longer a matter of course. Savings, bargain, hunters and complex systems undermine the much praised operational reliability. An analysis of the risks involved is an obvious measure to take. But the problem is: who feels responsible for the entire electricity supply structure?
[en] With restructuring of the power industry, competitive bidding for energy and ancillary services are increasingly recognized as an important part of electricity markets. It is desirable to optimize not only the generator's bid prices for energy and for providing minimized ancillary services but also the transmission congestion costs. In this paper, a hybrid approach of combining sequential dispatch with a direct search method is developed to deal with the multi-product and multi-area electricity market dispatch problem. The hybrid direct search method (HDSM) incorporates sequential dispatch into the direct search method to facilitate economic sharing of generation and reserve across areas and to minimize the total market cost in a multi-area competitive electricity market. The effects of tie line congestion and area spinning reserve requirement are also consistently reflected in the marginal price in each area. Numerical experiments are included to understand the various constraints in the market cost analysis and to provide valuable information for market participants in a pool oriented electricity market
[en] Highlights: • A defender–attacker–defender problem is set up with multiple uncertainty sets. • The probabilities of uncertainty sets are obtained by analytic hierarchy process. • The effect of load types on the proposed model is investigated. • The proposed model is solved by the column-and-constrains generation algorithm. - Abstract: To handle rapidly growing threats from deliberate attacks, the critical components in power grid should be identified and protected. This paper proposed a defender–attacker–defender model to deal with power grid protection problem, in which the uncertain attacks and load types are considered. Furthermore, multiple uncertainty sets are introduced to characterize the possible realizations of disruptions caused by attackers, and the probabilities of the multiple uncertainty sets are estimated using analytic hierarchy process. Then, the problem is formulated as a multi-uncertainty-set based two-stage robust optimization model which can be termed as a mixed-integer tri-level programming and solved by column-and-constrains generation algorithm with a master-subproblem framework. The test results on a standard IEEE RTS 24-bus system show the effectiveness of the proposed model by considering multiple uncertainty sets and load types.