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Optimização da exploração de curto prazo e das ofertas em mercado para um sistema electroprodutor considerando incerteza e risco

Publication . Pousinho, Hugo Miguel Inácio

Esta tese incide sobre a previsão e a exploração de curto prazo em sistemas electroprodutores hídricos e eólicos. O objectivo é uma contribuição no âmbito quer das metodologias de previsão quer das estratégias de oferta em mercado de electricidade, considerando incerteza e risco. Novas metodologias de optimização são propostas para captar as consequências associadas ao comportamento do mercado de electricidade. A previsão da potência eólica e dos preços da energia eléctrica têm que contemplar exigências quer de informação limitada quer de viabilidade no que respeita aos recursos computacionais. Metodologias hibridas que combinam a WT, o PSO e o ANFIS vão ao encontro de soluções que originam estratégias económicas mais favoráveis para as empresas produtoras, contribuindo para contemplar as exigências anteriores. Estas metodologias auxiliam a optimização da exploração tendo em consideração o carácter estocástico das variáveis envolvidas no problema. O desenvolvimento de metodologias estocásticas possibilita mitigar a incerteza pela consideração de cenários que permitem à empresa produtora uma exploração de forma viável e fiável em ambiente competitivo, acedendo com níveis superiores de racionalidade às estratégias de licitações no mercado, que consideram a ponderação de risco na tomada de decisões. Para comprovar a proficiência das metodologias desenvolvidas são utilizados casos de estudo a onde, através dos resultados obtidos, é possível concluir sobre o seu desempenho favorável

2012-05Doctoral thesis

Open access

Forecasting tools and probabilistic scheduling approach incorporatins renewables uncertainty for the insular power systems industry

Publication . Silva, Gerardo José Osório da; Catalão, João Paulo da Silva; Matias, João Carlos de Oliveira

Nowadays, the paradigm shift in the electricity sector and the advent of the smart grid, along with the growing impositions of a gradual reduction of greenhouse gas emissions, pose numerous challenges related with the sustainable management of power systems. The insular power systems industry is heavily dependent on imported energy, namely fossil fuels, and also on seasonal tourism behavior, which strongly influences the local economy. In comparison with the mainland power system, the behavior of insular power systems is highly influenced by the stochastic nature of the renewable energy sources available. The insular electricity grid is particularly sensitive to power quality parameters, mainly to frequency and voltage deviations, and a greater integration of endogenous renewables potential in the power system may affect the overall reliability and security of energy supply, so singular care should be placed in all forecasting and system operation procedures. The goals of this thesis are focused on the development of new decision support tools, for the reliable forecasting of market prices and wind power, for the optimal economic dispatch and unit commitment considering renewable generation, and for the smart control of energy storage systems. The new methodologies developed are tested in real case studies, demonstrating their computational proficiency comparatively to the current state-of-the-art.

2015Doctoral thesis

Open access

Modeling a cooperation environment for flexibility enhancement in smart multi-energy industrial systems

Publication . Damavandi, Maziar Yazdani; Catalão, João Paulo da Silva; Matias, João Carlos de Oliveira

Environmental aspects have been highlighted in architecting future energy systems where sustainable development plays a key role. Sustainable development in the energy sector has been deﬁned as a potential solution for enhancing the energy system to meet the future energy requirements without interfering with the environment and energy provision. In this regard, studying the cross-impact of various energy vectors and releasing their inherent operational ﬂexibility is main topic. Thecoordinationofvariousenergyvectorsundertheconceptofmulti-energysystem (MES)hasintroducednewsourcesofoperationalﬂexibilitytothesystemmanagers. MES considers both interactions among the energy carriers and the decision makers in an interdependent environment to increase the total eﬃciency of the system and reveal the hidden synergy among energy carriers. This thesis addresses a framework for modeling multi-energy players (MEP) that are coupled based on price signal in multi-energy system (MES) in a competitive environment. MEP is deﬁned as an energy player who can consume or deliver more than one type of energy carriers. At ﬁrst, the course of evolution for the energy system from today independent energy systems to a fully integrated MES is presented and the fractal structure is described for of MES architecture. Moreover, the operational behavior of plug-in electric vehicles’ parking lots and multi-energy demands’ external dependency are modeled in MES framework to enhance the operational ﬂexibility of local energy systems (LES). In the fractal environment, there exist conﬂicts among MEPs’ decision making in a same layer and other layers. Realizing the inherent ﬂexibility of MES is the main key for modeling the conﬂicts in this multi-layer structure. The conﬂict between two layers of players is modeled based on a bi-level approach. In this problem, the ﬁrst level is the MEP level where the player maximizes its proﬁt while satisfying LES energy exchange. The LES’s exchange energy price is the output of this level. In the lower level, the LESs schedule their energy balance, based on the upper level input price signal. The problem is transformed into a mathematical program with equilibrium constraint (MPEC) through duality theory. In the next step, high penetration of multi-energy players in the electricity market is modeled and their impacts on electricity market equilibrium are investigated. In such a model, MEP participates in the local energy and wholesale electricity markets simultaneously. MEP and the other players’ objectives in these two markets conﬂict with each other. Each of these conﬂicts is modeled based on bi-level programming. The bi-level problems are transformed into a single level mixed-integer linear problem by applying duality theory.

2016-07Doctoral thesis

Open access