ABB is a multinational corporation headquartered in Zurich, Switzerland, operating mainly in robotics and the power and automation technology areas. It ranked 158th in the Forbes Ranking .ABB is one of the largest engineering companies as well as one of the largest conglomerates in the world. ABB has operations in around 100 countries, with approximately 150,000 employees in November 2013, and reported global revenue of $40 billion for 2011.ABB is traded on the SIX Swiss Exchange in Zürich and the Stockholm Stock Exchange in Sweden since 1999, the New York Stock Exchange in the United States since 2001, September 2005 on London Stock Exchange and in November 2005 on the Frankfurt Stock Exchange. Wikipedia.
Performance Evaluation | Year: 2010
Performance prediction and measurement approaches for component-based software systems help software architects to evaluate their systems based on component performance specifications created by component developers. Integrating classical performance models such as queueing networks, stochastic Petri nets, or stochastic process algebras, these approaches additionally exploit the benefits of component-based software engineering, such as reuse and division of work. Although researchers have proposed many approaches in this direction during the last decade, none of them has attained widespread industrial use. On this basis, we have conducted a comprehensive state-of-the-art survey of more than 20 of these approaches assessing their applicability. We classified the approaches according to the expressiveness of their component performance modelling languages. Our survey helps practitioners to select an appropriate approach and scientists to identify interesting topics for future research. © 2010 Elsevier B.V. All rights reserved. Source
IEEE Transactions on Smart Grid | Year: 2014
The necessity of an AC or DC microgrid is governed by available micro sources and connected loads. A hybrid structure can ensure a sustainable configuration blending both the forms. In this paper, a hybrid microgrid structure for a grid connected microgrid with DC connection at back to back (B2B) converters is proposed. While a B2B connection between two AC systems could bestow a reliable, isolated and efficient coupling, an extra DC bus connection can facilitate use of the DC micro sources. The DC bus can supply the local DC loads and can also trade part of the power with the AC grids. The voltage support at the DC link (of the B2B converters) can be used for the DC bus formation. Different power management strategies with fixed power references or decentralized power distribution in AC/DC sides are proposed and validated with simulations in PSCAD. © 2013 IEEE. Source
IEEE Transactions on Power Delivery | Year: 2013
Islanding detection methods can be divided into communication-based and local detection-based methods. Proposed local passive detection methods have traditionally been dependent on the distributed generation unit type. A large nondetection zone (NDZ) near a power balance situation and unwanted distributed generation tripping due to other network events have also been major drawbacks of traditional, passive local islanding detection methods. In this paper, a new passive local multicriteria-based islanding detection algorithm with fault detection and islanding verification logic is presented. This new islanding detection algorithm, measuring voltage unbalance and voltage total harmonic distortion from all phases, is able to detect very fast and selectively islanding situations in a perfect power balance without NDZ with a simultaneous utilization of the available fault detection information and novel islanding verification logic. In addition to the new multicriteria-based islanding detection method, the fault detection information and islanding verification logic could also be used together with any other known passive islanding detection methods, that is, parameters which are not specified in the fault-ride-through (FRT) requirements of the future grid codes, to improve the performance of these methods in terms of reliability and speed of detection. © 1986-2012 IEEE. Source
IEEE Transactions on Power Systems | Year: 2013
This paper investigates some aspects of stability in microgrids. There are different types of microgrid applications. The system structure and the control topology vary depending on the application and so does the aspect of stability in a microgrid. This paper briefly encompasses the stability aspects of remote, utility connected and facility microgrids depending on the modes of operation, control topology, types of micro sources and network parameters. The small signal, transient and the voltage stability aspects in each type of the microgrid are discussed along with scope of improvements. With a brief review of the existing microgrid control methods in the literature and different industry solutions, this paper sets up an initial platform for different types of microgrids stability assessment. Various generalized stability improvement methods are demonstrated for different types of microgrids. The conventional stability study of microgrids presented in this paper facilitates an organized way to plan the micro source operation, microgrid controller design, islanding procedure, frequency control and the load shedding criteria. The stability investigations are presented with different control methods, eigen value analysis and time domain simulations to justify different claims. © 1969-2012 IEEE. Source
Agency: Cordis | Branch: H2020 | Program: IA | Phase: LCE-03-2015 | Award Amount: 13.71M | Year: 2016
The FloTEC project will demonstrate the potential for floating tidal stream turbines to provide low-cost, high-value energy to the European grid mix. The FloTEC project has 5 core objectives: 1. Demonstrate a full-scale prototype floating tidal energy generation system for optimised energy extraction in locally varying tidal resources; 2. Reduce the Levelised Cost of Energy of floating tidal energy from current estimated 250/MWh to 200/MWh, through both CAPEX and OPEX cost reductions in Scotrenewables Tidal Technology; 3. Develop potential of tidal energy generation towards flexible, baseload generation, through the integration of energy storage. 4. Demonstrate the potential for centralised MV power conversion to provide a generic, optimised low-cost solution for tidal arrays 5. Progress tidal energy towards maturity and standard project financing by reducing cost and risk, improving reliability, and developing an advanced financing plan for first arrays. This will be realised through the construction of a M2-SR2000 2MW turbine - which will incorporate the following innovations: 50% greater energy capture through enlarged rotors with a lower rated speed; Automated steel fabrication; Centralised MV power conversion Integrated Energy Storage Mooring load dampers Composite Blade Manufacturing The SR2000-M2 will be deployed alongside the existing SR2000-M1 at EMEC to form a 4MW floating tidal array, serving as a demonstration platform for commercially viable tidal stream energy as a baseload supply.