Loading...
Search for: physical-constraints
0.017 seconds

    Trajectory design for cooperative combat missions

    , Article 2008 IEEE Aerospace Conference, AC, Big Sky, MT, 1 March 2008 through 8 March 2008 ; 2008 ; 1095323X (ISSN) ; 1424414881 (ISBN); 9781424414888 (ISBN) Tavakoli Kashi, A ; Sharif University of Technology
    2008
    Abstract
    In this paper, a hierarchical method for trajectory design for cooperative combat missions (CCM) is presented. In a military environment, in addition to physical constraints (aircraft dynamics and mountains) there are threats made by Radars or Artillery. So an important constraint, "Avoid Threats", is added to physical constraints. Major steps in trajectory design are: "Target Assignment", "Path Planning", "Path Smoothing and Trajectory Design". The most important points and a brief algorithm for each step is presented in this paper. Finally the method is applied to special case and the results presented. ©2008 IEEE  

    Optimal control of an aerial tail sitter in transition flight phases

    , Article Journal of Aircraft ; Volume 53, Issue 4 , Volume 53, Issue 4 , 2016 , Pages 914-921 ; 00218669 (ISSN) Banazadeh, A ; Taymourtash, N ; Sharif University of Technology
    American Institute of Aeronautics and Astronautics Inc 
    Abstract
    The main purpose of this study is to generate optimal transition trajectories for an aerial tail sitter that uses cross-coupled thrust-vectoring control. A transition maneuver is most challenging for such configurations due to coupling of the forces and moments with instability in the most critical low-speed flight phases. Based on the classical Cauchy method, an improved gradient-based algorithm is developed in a collaborative process in order to find transition trajectories and increase the convergence rate. The cost function is defined in terms of minimum time in transition from hover to cruise and minimum altitude variations from cruise to hover. In addition, physical constraints are... 

    An approach to optimal dispatch of bilateral electricity contracts regarding voltage stability

    , Article IFAC Proceedings Volumes (IFAC-PapersOnline) ; Volume 5, Issue PART 1 , 2006 , Pages 65-70 ; 14746670 (ISSN); 9783902661081 (ISBN) Mozafari, B ; Ranjbar, A. M ; Mozafari, A ; Amraee, T ; Sharif University of Technology
    IFAC Secretariat  2006
    Abstract
    This paper proposes a methodology for optimal dispatch of bilateral electricity contracts, which may endanger the system voltage stability in light of short-term operational planning of a deregulated power system. In this framework the value that each owner of a transaction is willing to pay will reflect how much the electricity contract is important to be implemented physically. The proposed model dispatches optimally the bilateral transactions regarding the prices offered by owners of bilateral contracts for reactive power and transmission capacity utilization in one hand and, the total operational costs of reactive power resources in the other hand. The model also includes the limits... 

    Probabilistic multistage PMU placement in electric power systems

    , Article IEEE Transactions on Power Delivery ; Vol. 26, issue. 2 , 2011 , p. 841-849 ; ISSN: 08858977 Aminifar, F ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Khodaei, A ; Sharif University of Technology
    Abstract
    This paper presents an optimization model for the calculation of the minimum number of phasor measurement units (PMUs) in electrical power networks. The problem constraint is a predefined probability of observability associated with each bus. The mixed-integer programming is used for the proposed optimization and an efficient linearization technique is proposed to convert the nonlinear function representing the probability of observability into a set of linear expressions. The PMU placement is staged in a multi-year planning horizon due to financial and physical constraints. The average probability of observability is maximized at the intermediate planning stages, subject to a limited number... 

    Probabilistic multistage PMU placement in electric power systems

    , Article IEEE Transactions on Power Delivery ; Volume 26, Issue 2 , December , 2011 , Pages 841-849 ; 08858977 (ISSN) Aminifar, F ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Khodaei, A ; Sharif University of Technology
    2011
    Abstract
    This paper presents an optimization model for the calculation of the minimum number of phasor measurement units (PMUs) in electrical power networks. The problem constraint is a predefined probability of observability associated with each bus. The mixed-integer programming is used for the proposed optimization and an efficient linearization technique is proposed to convert the nonlinear function representing the probability of observability into a set of linear expressions. The PMU placement is staged in a multi-year planning horizon due to financial and physical constraints. The average probability of observability is maximized at the intermediate planning stages, subject to a limited number... 

    Multi objective power system restoration

    , Article 2008 IEEE Electrical Power and Energy Conference - Energy Innovation, Vancouver, BC, 6 October 2008 through 7 October 2008 ; January , 2008 ; 9781424428953 (ISBN) Nouri Zadeh, S ; Ranjbar, A. M ; Sharif University of Technology
    2008
    Abstract
    This paper presents a stochastic model for optimal generating units' restoration planning. Restoration plans will be performed based on different objectives i.e. total system risk, total served energy in the period of restoration, and total restoration time. The proposed model is a multi objective stochastic program in which generating units' restoration plan is assumed to optimize different kinds of objective function. The proposed approach to the optimal restoration of generating units can be used by vertically integrated utilities as well as the ISOs in electricity markets. The approach coordinates the optimal start up of generating units within the restoration period. Physical...