Stochastic approach for active and reactive power management in distribution networks

YesIn this paper, a stochastic method is proposed to assess the amount of active and reactive power that can be injected/absorbed to/from grid within a distribution market environment. Also, the impact of wind power penetration on the reactive and active distribution-locational marginal prices is investigated. Market-based active and reactive optimal power flow is used to maximize the social welfare considering uncertainties related to wind speed and load demand. The uncertainties are modeled by Scenario-based approach. The proposed model is examined with 16-bus UK generic distribution system.Supported by the Higher Education Ministry of Iraqi government

Active distribution networks planning with high penetration of wind power

YesIn this paper, a stochastic method for active distribution networks planning within a distribution market environment considering multi-configuration of wind turbines is proposed. Multi-configuration multi-scenario market-based optimal power flow is used to maximize the social welfare considering uncertainties related to wind speed and load demand and different operational status of wind turbines (multiple-wind turbine configurations). Scenario-based approach is used to model the abovementioned uncertainties. The method evaluates the impact of multiple-wind turbine configurations and active network management schemes on the amount of wind power that can be injected into the grid, the distribution locational marginal prices throughout the network and on the social welfare. The effectiveness of the proposed method is demonstrated with 16-bus UK generic distribution system. It was shown that multi-wind turbine configurations under active network management schemes, including coordinated voltage control and adaptive power factor control, can increase the amount of wind power that can be injected into the grid; therefore, the distribution locational marginal prices reduce throughout the network significantly

A deterministic approach for active distribution networks planning with high penetration of wind and solar power

YesIn this paper, a novel deterministic approach for the planning of active distribution networks within a distribution market environment considering multi-configuration of wind turbines (WTs) and photovoltaic (PV) cells is proposed. Multi-configuration multi-period market-based optimal power flow is utilized for maximizing social welfare taking into account uncertainties associated with wind speed, solar irradiance and load demand as well as different operational status of WTs and PVs. Multi-period scenarios method is exploited to model the aforementioned uncertainties. The proposed approach assesses the effect of multiple-configuration of PVs and WTs on the amount of wind and solar power that can be produced, the distribution locational marginal prices all over the network and on the social welfare. The application of the proposed approach is examined on a 30-bus radial distribution network.This work was supported in part by the Royal Academy of Engineering Distinguished Visiting Fellowship Grant DVF1617/6/45 and by the University of Bradford, UK under the CCIP grant 66052/000000

Active Distribution Networks Planning Considering Multi-DG Configurations and Contingency Analysis

YesThis paper proposes a novel method for planning active distribution networks (ADNs) with the integration of an active network management (ANM) scheme using coordinated voltage control (CVC) through on-load tap changer (OLTC) transformers. The method was formulated as a security-constrained optimal power flow (SCOPF) problem to minimize total operational costs, which maximizes the utilization of renewable distributed generators (DGs) over a planning horizon. The ANM scheme was applied using OLTC to ensure safe operation and reduce voltage violations in the network. To analyse the impact of ANM, the planning problem was examined both with and without the ANM scheme. Moreover, SCOPF, considering the N-1 line contingency analysis and multi-DG configuration, was implemented to analyse the feasibility of the proposed method and the advantages of ANM under contingency situations. The method was validated on a weakly-meshed 16-bus UK generic distribution system (UKGDS). The results showed that ANM can lower operational costs and maintain network voltage for operation in feasible conditions even in the case of a contingency. Moreover, the ANM scheme mitigated the voltage rise effect caused by DGs and maximized their utilization

Optimal operation of hybrid AC/DC microgrids under uncertainty of renewable energy resources : A comprehensive review

The hybrid AC/DC microgrids have become considerably popular as they are reliable, accessible and robust. They are utilized for solving environmental, economic, operational and power-related political issues. Having this increased necessity taken into consideration, this paper performs a comprehensive review of the fundamentals of hybrid AC/DC microgrids and describes their components. Mathematical models and valid comparisons among different renewable energy sources’ generations are discussed. Subsequently, various operational zones, control and optimization methods, power flow calculations in the presence of uncertainties related to renewable energy resources are reviewed.fi=vertaisarvioitu|en=peerReviewed

Determinação do ponto ótimo de conexão de parques eólicos offshore a sistemas interligados considerando a maximização da capacidade de geração de energia

Due to growing environmental issues and depletion of conventional energy sources, alternative energy sources, especially renewable ones, are receiving more attention than ever. In this sense, wind energy is one of the most prominent in the context of investments in renewable sources in Brazil and globally. In some cases, regions with high potential for wind generation are far from load centers and are located in a maritime environment; in such situations, it makes sense to install wind farms in an offshore environment. In this scenario, a comprehensive analysis is required to determine the optimal connection point for Offshore Wind Farms (OWF) to the network to ensure maximum wind generation penetration safely and efficiently, taking into account such aspects as load profile, conventional system power generations, impacts caused by intermittent renewable energy sources in grid operation, capacity constrains of the transmission line and wind speed behavior of all the potential regions under study. In this context, this paper aims to propose two methodologies for determining the optimum OWF connection point to interconnected systems while considering how to maximize the capacity for power generation. The first methodology proposes a formulation based on Nonlinear Programming with Linear Power Flow (NLP-DC), where it is possible to observe the wind generation penetration path to the system until the maximum viable value is obtained, considering the minimization of losses in the transmission system and presenting an efficient strategy for the incorporation of active restrictions regarding the “N-1” safety criterion. The second method addresses a computationally efficient optimization problem, which proposes a two-step formulation, both based on Nonlinear Programming (NLP) with a Nonlinear Power Flow approach, which determines the optimum OWF connection point, with their respective maximum wind generation penetration and generating capacity values, considering all contingency scenarios (“N-1” safety criterion), modeled here with the help of the Benders Mathematical Decomposition technique. The proposed methodologies are applied in small, medium and large test systems in order to explore their characteristics and their contributions. Studies in small and medium-sized systems allow for a more tutorial analysis of the problem, while studies of real large systems are able to demonstrate the applicability and effectiveness of the proposed methodology in practical cases.Devido às crescentes questões relacionadas ao meio ambiente e ao esgotamento de fontes de energia convencionais, as fontes alternativas de energia, principalmente as renováveis, estão recebendo mais atenção do que nunca. Nesse sentido, a energia eólica é uma das que apresentam maior destaque na conjuntura de investimentos em fontes renováveis no cenário brasileiro e mundial. Em alguns casos, as regiões com alto potencial de geração eólica estão longe dos centros de carga e localizadas em ambiente marítimo; em situações como essa, torna-se interessante a instalação de parques eólicos em ambiente offshore. Nesse cenário, é necessária uma análise abrangente para se determinar o ponto ótimo de conexão de Parques Eólicos Offshore (PEO) à rede principal que garanta a máxima penetração de geração eólica, de forma segura e eficiente, levando-se em consideração questões como o perfil de carga, as gerações convencionais de energia existentes no sistema, os impactos causados pela inserção de fontes de energia renováveis intermitentes na operação da rede, as restrições relacionadas às capacidades das linhas de transmissão e o comportamento da velocidade do vento de todas as regiões potenciais em estudo. Nesse contexto, este trabalho tem por objetivo propor duas metodologias para a determinação do ponto ótimo de conexão de PEO a sistemas interligados considerando a maximização da capacidade de geração de energia. Na primeira metodologia é proposta uma formulação baseada em Programação Não Linear associada a um Fluxo de Potência Linearizado (PNL-CC), em que é possível observar a trajetória de penetração de geração eólica ao sistema até se obter o valor máximo viável, considerando-se a minimização de perdas no sistema de transmissão e apresentando uma estratégia eficiente para a incorporação das restrições ativas referentes ao critério de segurança “N-1”. O segundo método aborda um problema de otimização computacionalmente mais eficiente, em que se propõe uma formulação dividida em duas etapas, ambas baseadas em Programação Não Linear e com uma abordagem de Fluxo de Potência CA (PNL-CA), que determina o ponto ótimo de conexão do PEO, com seus respectivos valores máximos de penetração de geração eólica e de capacidade de geração, considerando-se todos os cenários de contingência (critério de segurança “N-1”), modelados através da técnica de Decomposição Matemática de Benders. As metodologias propostas são aplicadas a sistemas-testes de pequeno, médio e grande porte, de forma a explorar suas características e suas contribuições. Os estudos realizados em sistemas de pequeno e médio porte permitem uma análise do problema com cunho mais tutorial, enquanto que o estudo de sistemas reais de grande porte são capazes de demonstrar a aplicabilidade e eficácia das metodologias propostas em casos práticos.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio