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[en] SMES (Superconducting Magnetic Energy Storage) is an emerging technology offering tremendous potential benefits to the utility industry. San Diego Gas ampersand Electric (SDG ampersand E) and Bechtel are leading a team of companies and national laboratories working towards design and construction of the world's first demonstration facility for large, commercial SMES for enhancing transmission stability in the Southwestern United States
[en] The present study focuses on the relationship between the structural features and reversible shape memory effect (SME) including the related martensitic transformation (MT) in porous TiNi-based compounds fabricated by self-propagating high-temperature synthesis (SHS) at various ignition temperatures. Exploring the as-synthesized samples (S-1 and S-2) ignited at T 1 = 400 and T 2 = 600 °C, respectively, using a set of research instruments has revealed a key feature that modulates the resultant porous structure and SME parameters. Evidently, the one-step B2 ↔ B19′ MT in both samples is considered to be diffuse within a broad temperature gap, where the hysteresis loop width excels 70 degrees. The fine-porous S-1 indicated the well-developed macrostructure having a rough surface pattern of pore walls, whereas the high-porous S-2 did a dissimilar macrostructure having an even pore surface topology. From a phase-chemical point of view, the metal matrix of S-2 was found to be more homogeneous as compared to that of S-1, that in turn has led to the distinctive SME performance in terms of ε-T upon thermocycling. The extremely heterogeneous S-1 featured by more uniform pore shape and distribution has demonstrated the feasible strain behavior despite the fewer TiNi volume fraction and depressed MT was observed. Conversely, the SME performance for S-2 was shown to be impaired because of the discrepancy in the deformation behavior of small and large pore walls, even though the redundant TiNi volume fraction facilitated the MT. (paper)
[en] The evaluation of investments in longer term research and development in emerging technologies, because of the nature of such subjects, must address inherent uncertainties. Most notably, future cash flow forecasts include substantial uncertainties. Conventional present value methodology, when applied to emerging technologies severely penalizes cash flow forecasts, and strategic investment opportunities are at risk of being neglected. Use of options valuation methodology adapted from the financial arena has been introduced as having applicability in such technology evaluations. Indeed, characteristics of superconducting magnetic energy storage technology suggest that it is a candidate for the use of options methodology when investment decisions are being contemplated
[en] Superconducting magnetic energy storage (SMES) system can be long-term, efficient, non-destructive electric energy storage, the decoupling control can run in four quadrant, can achieve power active power and wattless power real-time fast independent adjustment. It is applied to the microgrid implemented through the SMES dynamic power compensation so as to greatly increase the initiative control of power grid operation. In this paper, the current source type SMES as the research object, the SMES system based on microgrid operation research. A microgrid PSCAD model including SMES system, SMES respectively provide short-term electricity, fault time buffer, improve microgrid power quality, micro smoothing grid and main network switching, optimization of DG improve the operation of microgrid operation economy of simulation study, provide a reference for SMES application in microgrid. (paper)
[en] Superconducting magnetic energy storage (SMES) systems offering flexible, reliable, and fast acting power compensation are applicable to power systems to improve power system stabilities and to advance power qualities. The authors have summarized researches on SMES applications to power systems. Furthermore, various SMES applications to power systems have been described briefly and some crucial schematic diagrams and equations are given. In addition, this study presents valuable suggestions for future studies of SMES applications to power systems. Hence, this paper is helpful for co-researchers who want to know about the status of SMES applications to power systems. (topical review)
[en] This article presents the thermal model of a small scale superconducting magnetic energy storage system with the closed cycle helium cryocooler. The authors propose the use of contact-cooled coils with maintaining the possibility of the system reconfiguring. The model assumes the use of the second generation superconducting tapes to make the windings in the form of flat discs (pancakes). The paper presents results for a field model of the single pancake coil and the winding system consisting of several coils.
[en] This paper proposes a new optimal fuzzy logic-based-proportional-integral-derivative (FLPID) controller for load frequency control (LFC) including superconducting magnetic energy storage (SMES) units. Conventionally, the membership functions and control rules of fuzzy logic control are obtained by trial and error method or experiences of designers. To overcome this problem, the multiple tabu search (MTS) algorithm is applied to simultaneously tune PID gains, membership functions and control rules of FLPID controller to minimize frequency deviations of the system against load disturbances. The MTS algorithm introduces additional techniques for improvement of search process such as initialization, adaptive search, multiple searches, crossover and restarting process. Simulation results explicitly show that the performance of the optimum FLPID controller is superior to the conventional PID controller and the non-optimum FLPID controller in terms of the overshoot, settling time and robustness against variations of system parameters
[en] The development of energy storage devices has been gaining in significance in the last few years. Advances made in this area of research and development might induce changes in the technical design concepts of electrical power supply systems, which eventually might lead to cost savings, among other things, in electricity supply. The technical requirements to be met by energy storage devices vary according to intended application. General goals of development work are: high loading/discharging efficiency; high energy and power output density; rapid controllability; favorable investment and operating costs. The paper addresses applications of interest to electric utility operators, as well as superconducting magnetic energy storage devices (SMES) for applications in a superconducting system environment. (orig.)
[de]Die Entwicklung von Energiespeichern gewann in den letzten Jahren stark an Bedeutung. Fortschitte koennten Aenderungen in den technischen Konzepten der elektrischen Energieversorgungssysteme bewirken, die nicht zuletzt auch eine kostenguenstigere Bereitstellung des Stromes zur Folge haben koennten. Die technischen Anforderungen unterscheiden sich je nach Einsatzgebiet. Generelle Entwicklungsziele sind - hoher Lade-/Entladewirkungsgrad; - grosse Energie- und Leistungsdichte; - schnelle Regelbarkeit; - guenstige Investitionen- und Betriebskosten. Im folgenden werden interessante Anwendungsmoeglichkeiten fuer Energiespeicher im EVU-Bereich naeher beleuchtet. Bei Anwendung der Supraleitung kommt als hier der Supraleitende Magnetische Energiespeicher (SMES) in Betracht. (orig.)
[en] The different activities in the field of applied superconductivity carried out in Spain under the auspices of the MIDAS program are reported. Applications using both low- and high-temperature superconductors are considered. In the low temperature superconductors case, the design and construction of a 1 mega joule SMES (Superconducting Magnetic Energy Storage) unit, as well as the fabrication of voltage and resistance standards, are reviewed. Developments involving the design and fabrication of an inductive current fault limited and mono- and multi-filamentary wires and tapes using high-temperature superconductors are discussed. Finally, the prospects for the application of superconductivity technology to electric power systems for the electric utilities is considered. (author)
[en] Highlights: • Four pillars of effective energy saving projects in SMEs were identified. • The four pillars are: the expertise, operational data, modeling and methodology. • An appropriate degree of simplification allows wider use of modeling and simulation. • A specialized testing facility is a great benefit for the data acquisition. Commonly used approaches in energy management have been found to be insufficient in many small and medium industrial enterprises. The benefits of energy saving solutions can be rather limited. A lack of procedures providing optimal solutions is noticeable from a literature review. Systematic and critical observations of numerous energy saving projects performed by the authors revealed that it is possible to specify four pillars which are crucial for successfully implementing these projects. They should be applied as much as possible and can be specified as follows:1. Technical expertise: Knowledge of industrial facility and possible savings based on experience 2. Good operational data: The acquisition of data in a facility 3. Modeling, simulation and optimisation: Assessment of various options and the selection of the most beneficial one 4. Methodology: A systematic approach including all three remaining pillars The benefits of each pillar have been demonstrated by several publications. This paper summarizes the pillars in a review study and introduces a systematic approach based on them. The four pillars were applied on various case studies. One of them is presented in the article. The application of all the pillars provides an efficient way to conduct energy saving projects.