Search or filter publications

Filter by type:

Filter by publication type

Filter by year:

to

Results

  • Showing results for:
  • Reset all filters

Search results

  • Journal article
    Casagrande D, Astolfi A, Ortega R, 2011,

    Asymptotic stabilization of passive systems without damping injection: A sampled integral technique

    , AUTOMATICA, Vol: 47, Pages: 262-271, ISSN: 0005-1098
  • Journal article
    Hui SYR, Lin DY, Ng WM, Yan Wet al., 2011,

    A "Class-A2" Ultra-Low-Loss Magnetic Ballast for T5 Fluorescent Lamps-A New Trend for Sustainable Lighting Technology

    , IEEE TRANSACTIONS ON POWER ELECTRONICS, Vol: 26, Pages: 622-629, ISSN: 0885-8993
  • Journal article
    Thambirajah J, Thornhill NF, Pal BC, 2011,

    A Multi­variate Approach Towards Inter-Area Oscillation Damping Estimation Under Ambient Conditions Via Independent Component Analysis And Random Decrement

    , IEEE Transactions on Power Systems, Vol: 26, Pages: 315-322, ISSN: 0885-8950

    This paper presents a novel approach to the monitoring of interarea oscillation frequency and damping using multivariate analysis techniques. A two-step method is presented 1) independent component analysis for the detection of interarea modes and estimation of their frequencies and 2) random decrement for the estimation of mode damping. The method is applied to real measurements taken in Finland within the Nordic Power System to estimate the critical interarea mode frequency and damping in the system.
  • Patent
    Plet CA, Green TC, Walton CM, 2011,

    Electrical Devices With Improved Fault Current Handling Capabilities

    An electrical device comprising: first and second windings that are magnetically coupled such that, during normal operation, magnetic fields of the first and second windings interact and currents flow through the first and second windings; and a power controller arranged to control the current in the second winding in a fault situation, so as to reduce or limit the current magnitude flowing in the first winding or the second winding, or to synchronise the magnetic field of the second winding with the magnetic field of the first winding and thereby reduce their interaction; wherein the second winding incorporates a tap changer arrangement operable to reduce the number of turns in the second winding through which the current in the second winding flows, and thereby decrease the mutual inductance between the first and second windings and reduce the voltage magnitude required of the power controller in order to exercise control in the fault situation.Also provided is a method of operating such a device, and a tap changer arrangement that is well suited for use with such a device
  • Conference paper
    Acha S, Green TC, Shah N, 2011,

    Optimal charging strategies of electric vehicles in the UK power market

    , 2011 IEEE PES Innovative Smart Grid Technologies (ISGT), Publisher: IEEE, Pages: 1-8

    In order to gain the most from their deployment, it is imperative for stakeholders to exploit the main benefits electric vehicles bring to utilities. Therefore, this paper focuses on the aspects required to model the management of electricity supply for electric vehicles. The framework presented details a time coordinated optimal power flow (TCOPF) tool to illustrate the tradeoffs distribution network operators (DNO) might encounter when implementing various load control approaches of electric vehicles. Within an UK context, a case study is performed where the TCOPF tool functions as the intermediary entity that coordinates cost-effective interactions between power markets, network operators, and the plugged vehicles. Results depict the stochastic but optimal charging patterns stakeholders might visualise from electric vehicles in local networks as they are operated to reduce energy and emission costs. Furthermore, results show current emission costs have a negligible weight in the optimisation process when compared to wholesale electricity costs.
  • Book chapter
    Giarré L, Falugi P, Badalamenti R, 2011,

    Hybrid LPV Modeling and Identification

    , Linear Parameter-Varying System Identification New Developments and Trends, Publisher: World Scientific, Pages: 11-39, ISBN: 9789814355452

    This review volume reports the state-of-the-art in Linear Parameter Varying (LPV) system identification.
  • Journal article
    Buchstaller D, Kerrigan EC, Constantinides GA, 2011,

    Sampling and controlling faster than the computational delay

    , IFAC Proceedings Volumes IFAC Papersonline, Vol: 44, Pages: 7523-7528, ISSN: 1474-6670

    For a sampled-data control system, the sampling period is chosen smaller than the computational delay, an approach we call intra-delay sampling. Utilising parallel computing architectures, it is shown that intra-delay sampling schemes are feasible and that they yield better performance than their slower sampling counterparts. © 2011 IFAC.
  • Journal article
    Shahzad A, Jones BL, Kerrigan EC, Constantinides GAet al., 2011,

    An efficient algorithm for the solution of a coupled Sylvester equation appearing in descriptor systems

    , Automatica, Vol: 47, Pages: 244-248, ISSN: 1873-2836

    Descriptor systems consisting of a large number of differential-algebraic equations (DAEs) usually arise from the discretization of partial differential-algebraic equations. This paper presents an efficient algorithm for solving the coupled Sylvester equation that arises in converting a system of linear DAEs to ordinary differential equations. A significant computational advantage is obtained by exploiting the structure of the involved matrices. The proposed algorithm removes the need to solve a standard Sylvester equation or to invert a matrix. The improved performance of this new method over existing techniques is demonstrated by comparing the number of floating-point operations and via numerical examples.
  • Journal article
    Ahmed S, Kerrigan EC, 2011,

    Robust static attitude determination via robust optimization

    , IFAC Proceedings Volumes IFAC Papersonline, Vol: 44, Pages: 5807-5812, ISSN: 1474-6670

    We address the problem of robust attitude determination using a static approach. In contrast to the dynamic approach, a static approach does not depend on the system dynamics. This approach only requires measurements of some vectors, such as the earth magnetic field, sun vector, etc in two different coordinate frames. These vectors, obtained from some sensor or a mathematical model, may not be accurate due to sensor errors and modeling inaccuracies. We consider all such errors as infinity-norm bounded uncertainties and our main focus is to obtain an attitude estimate, which is least sensitive to such uncertainties. We formulate a robust optimization (RO) problem with a quadratic cost and nonlinear constraints and propose a solution using a quaternion approach with an affine uncertainty parameterization. We transform the RO problem into a suboptimal minimization problem, which is non-convex but can be solved with a good initial guess using a nonlinear optimization solver. The results show a significant advantage of the proposed approach for the worst case uncertainties. © 2011 IFAC.
  • Conference paper
    Boem F, Pellegrino FA, Fenu G, Parisini Tet al., 2011,

    Trajectory clustering by means of Earth Mover's Distance

    , Pages: 4741-4746, ISSN: 1474-6670

    We propose a method for trajectory classification based on a general cluster-based methodology, that can be used both off-line in an unsupervised fashion, both on-line, classifying new trajectories or part of them. We use the Earth Mover's Distance (EMD) and we adapt it in order to employ it as a tool for trajectory clustering. We propose a novel effective method to identify the clusters' representatives by means of the p-median location problem. This methodology is able to manage different length and noisy trajectories and takes velocity profiles and stops into account. We discuss the experimental results and we compare our approach with other trajectory clustering methods. © 2011 IFAC.
  • Journal article
    Boem F, Ferrari RMG, Parisini T, 2011,

    Distributed Fault Detection and Isolation of Continuous-Time Non-Linear Systems

    , EUROPEAN JOURNAL OF CONTROL, Vol: 17, Pages: 603-620, ISSN: 0947-3580
  • Conference paper
    Mayne DQ, Kerrigan EC, Falugi P, 2011,

    Robust model predictive control: Advantages and disadvantages of tube-based methods

    , Pages: 191-196, ISSN: 1474-6670

    An important reason for the success of model predictive control is the fact that, for deterministic systems, feedback and open-loop control are equivalent so that 'optimal' (but implicit) feedback may be obtained by solving an open-loop optimal control problem at each state encountered. This equivalence is not maintained in the presence of uncertainty complicating the development of robust model predictive control. The advantages and limitations of tubebased model predictive control for dealing with uncertainty of various forms are discussed, firstly in the context of constrained linear systems, and an extension to deal with robustness against unstructured uncertainty is briefly described. Tube-based control requires the determination both of a nominal or reference trajectory and an ancillary controller that constrains deviations of the state of the uncertain systems from the nominal trajectory and is difficult to extend to nonlinear systems. A novel ancillary controller for tube-based control of constrained nonlinear systems with additive disturbances that overcomes some disadvantages of a previous version and is relatively simple to implement is described and assessed; the addition of a terminal equality constraint to the nominal optimal control problem and its removal from the ancillary optimal control problem simplifies the analysis, removes some restrictive assumptions, and enables stronger results to be obtained. © 2011 IFAC.
  • Journal article
    Angeli D, Kountouriotis PA, 2011,

    Decentralized random control of refrigerator appliances

    , IFAC Proceedings Volumes IFAC Papersonline, Vol: 44, Pages: 12144-12149, ISSN: 1474-6670

    This paper considers the problem of dynamic demand management of domestic refrigerators. Dynamic demand management is a promising research direction, which aims to improve power system resilience, by dynamically controlling the energy consumption of devices that exhibit thermal energy storage. In this approach, the operating temperature of appliances, and thus their energy consumption, is modified dynamically, within a safe range, in response to mains frequency fluctuations. Such an operating scheme aims at reducing the strain that the demand side introduces in a power network, when the corresponding supply is temporarily disrupted. Previous research has highlighted the potential of this idea for responding to sudden power plant outages. However, deterministic control schemes have proved inadequate as individual appliances tend to "synchronize" with each other, leading to unacceptable levels of overshoot in energy demand, when they "recover" their steady-state operating cycles. In this paper we describe random controllers that are able to respond to sudden plant outages and which avoid the instability phenomena associated with other feedback strategies. Stochasticity is used to achieve desynchronization of individual refrigerators while keeping overall power consumption tightly regulated. © 2011 IFAC.
  • Journal article
    Mancarella P, Gan CK, Strbac G, 2011,

    Optimal design of low-voltage distribution networks for CO<sub>2</sub> emission minimisation. Part II: Discrete optimisation of radial networks and comparison with alternative design strategies

    , IET GENERATION TRANSMISSION & DISTRIBUTION, Vol: 5, Pages: 47-56, ISSN: 1751-8687
  • Journal article
    Mancarella P, Gan CK, Strbac G, 2011,

    Optimal design of low-voltage distribution networks for CO<sub>2</sub> emission minimisation. Part I: model formulation and circuit continuous optimisation

    , IET GENERATION TRANSMISSION & DISTRIBUTION, Vol: 5, Pages: 38-46, ISSN: 1751-8687
  • Journal article
    Chaudhuri NR, Chakraborty D, Chaudhuri B, 2011,

    An Architecture for FACTS Controllers to Deal With Bandwidth-Constrained Communication

    , IEEE TRANSACTIONS ON POWER DELIVERY, Vol: 26, Pages: 188-196, ISSN: 0885-8977
  • Journal article
    Pin G, Parisini T, 2011,

    Networked Predictive Control of Uncertain Constrained Nonlinear Systems: Recursive Feasibility and Input-to-State Stability Analysis

    , IEEE TRANSACTIONS ON AUTOMATIC CONTROL, Vol: 56, Pages: 72-87, ISSN: 0018-9286
  • Conference paper
    Singh R, Manitsas E, Pal BC, Strbac Get al., 2011,

    A Recursive Bayesian Approach for Identification of Network Configuration Changes in Distribution System State Estimation

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Sassano M, Astolfi A, 2011,

    Dynamic Disturbance Attenuation and Approximate Optimal Control for Fully Actuated Mechanical Systems

    , American Control Conference (ACC), Publisher: IEEE, Pages: 894-899, ISSN: 0743-1619
  • Conference paper
    Plet CA, Brucoli M, McDonald JDF, Green TCet al., 2011,

    Fault Models of Inverter-Interfaced Distributed Generators: Experimental Verification and Application to Fault Analysis

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Strbac G, Moreno R, Pudjianto D, Castro Met al., 2011,

    Towards a Risk-Based Network Operation and Design Standards

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Bloemink JM, Green TC, 2011,

    Increasing Photovoltaic Penetration with Local Energy Storage and Soft Normally-Open Points

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Chaudhuri NR, Chakraborty D, Chaudhuri B, 2011,

    An Architecture for FACTS Controllers to Deal With Bandwidth-Constrained Communication

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Chaudhuri NR, Chaudhuri B, 2011,

    Damping and Relative Mode-Shape Estimation in Near Real-Time Through Phasor Approach

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Chaudhuri NR, Chaudhuri B, 2011,

    Impact of Wind Penetration and HVDC Upgrades on Dynamic Performance of Future Grids

    , General Meeting of the IEEE-Power-and-Energy-Society (PES), Publisher: IEEE, ISSN: 1944-9925
  • Conference paper
    Ahmed S, Kerrigan EC, Jaimoukha IM, 2011,

    Semidefinite Relaxation of a Robust Static Attitude Determination Problem

    , 50th IEEE Conference of Decision and Control (CDC)/European Control Conference (ECC), Publisher: IEEE, Pages: 5337-5342, ISSN: 0743-1546
  • Conference paper
    Astolfi A, Praly L, 2011,

    A LaSalle version of Matrosov theorem

    , 50th IEEE Conference of Decision and Control (CDC)/European Control Conference (ECC), Publisher: IEEE, Pages: 320-324, ISSN: 0743-1546
  • Conference paper
    Yalcin Y, Astolfi A, 2011,

    Discrete Time Immersion and Invariance Adaptive Control for Systems in Strict Feedback Form

    , 50th IEEE Conference of Decision and Control (CDC)/European Control Conference (ECC), Publisher: IEEE, Pages: 343-347, ISSN: 0743-1546
  • Conference paper
    Ionescu TC, Astolfi A, 2011,

    Moment matching for linear port Hamiltonian systems

    , 50th IEEE Conference of Decision and Control (CDC)/European Control Conference (ECC), Publisher: IEEE, Pages: 7164-7169, ISSN: 0743-1546
  • Conference paper
    Sassano M, Astolfi A, 2011,

    Approximate Finite-Horizon Optimal Control without PDE's

    , 50th IEEE Conference of Decision and Control (CDC)/European Control Conference (ECC), Publisher: IEEE, Pages: 1716-1721, ISSN: 0743-1546

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://www.imperial.ac.uk:80/respub/WEB-INF/jsp/search-t4-html.jsp Request URI: /respub/WEB-INF/jsp/search-t4-html.jsp Query String: id=955&limit=30&page=31&respub-action=search.html Current Millis: 1766346278748 Current Time: Sun Dec 21 19:44:38 GMT 2025