CPES - Indexed Articles in Journals

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    Dynamic security of islanded power systems with pumped storage power plants for high renewable integration – A study case
    ( 2019) Helena Vasconcelos ; Beires,P ; Carlos Moreira ; João Peças Lopes ; 1103 ; 3348 ; 4442
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    An advanced platform for power system security assessment accounting for forecast uncertainties
    ( 2019) Ciapessoni,E ; Cirio,D ; Pitto,A ; Omont,N ; Leonel Magalhães Carvalho ; Vasconcelos,MH ; 3348 ; 4971
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    A methodology to evaluate the uncertainties used to perform security assessment for branch overloads
    ( 2019) Helena Vasconcelos ; Carla Silva Gonçalves ; Meirinhos,J ; Omont,N ; Pitto,A ; Ceresa,G ; 6595 ; 3348
    This paper presents a generic framework to evaluate and compare the quality of the uncertainties provided by probabilistic forecasts of power system state when used to perform security assessment for branch overloads. Besides exploiting advanced univariate and multivariate metrics that are traditionally used in weather prediction, the evaluation is complemented by assessing the benefits from exploiting probabilistic forecasts over the current practices of using deterministic forecasts of the system operating conditions. Another important feature of this framework is the provision of parameters tuning when applying flow probabilistic forecasts to perform security assessment for branch overloads. The quality and scalability of this framework is demonstrated and validated on recent historical data of the French transmission system. Although being developed to address branch overload problems, with proper adaptations, this work can be extended to other power system security problems. © 2019 Elsevier Ltd
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    Simulated annealing to handle energy and ancillary services joint management considering electric vehicles
    ( 2016) Sousa,T ; Tiago André Soares ; Morals,H ; Castro,R ; Vale,Z ; 6611
    The massive use of distributed generation and electric vehicles will lead to a more complex management of the power system, requiring new approaches to be used in the optimal resource scheduling field. Electric vehicles with vehicle-to-grid capability can be useful for the aggregator players in the mitigation of renewable sources intermittency and in the ancillary services procurement. In this paper, an energy and ancillary services joint management model is proposed. A simulated annealing approach is used to solve the joint management for the following day, considering the minimization of the aggregator total operation costs. The case study considers a distribution network with 33-bus, 66 distributed generation and 2000 electric vehicles. The proposed simulated annealing is matched with a deterministic approach allowing an effective and efficient comparison. The simulated annealing presents a solution closer to the one obtained in the deterministic approach (1.03% error), yet representing 0.06% of the deterministic approach CPU time performance.
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    Proactive management of distribution grids with chance-constrained linearized AC OPF
    ( 2019) Tiago André Soares ; Ricardo Jorge Bessa ; 4882 ; 6611
    Distribution system operators (DSO) are currently moving towards active distribution grid management. One goal is the development of tools for operational planning of flexibility from distributed energy resources (DER) in order to solve potential (predicted) congestion and voltage problems. This work proposes an innovative flexibility management function based on stochastic and chance-constrained optimization that copes with forecast uncertainty from renewable energy sources (RES). Furthermore, the model allows the decision-maker to integrate its attitude towards risk by considering a trade-off between operating costs and system reliability. RES forecast uncertainty is modeled through spatial-temporal trajectories or ensembles. An AC-OPF linearization that approximates the actual behavior of the system is included, ensuring complete convexity of the problem. McCormick and big-M relaxation methods are compared to reformulate the chance-constrained optimization problem. The discussion and comparison of the proposed models is carried out through a case study based on actual generation data, where operating costs, system reliability and computer performance are evaluated.