Browsing by Author "Ramos, Sérgio Filipe Carvalho"
Now showing 1 - 10 of 15
Results Per Page
Sort Options
- Charge/Discharge Scheduling of Electric Vehicles and Battery Energy Storage in Smart Building: a Mix Binary Linear Programming modelPublication . Foroozandeh, Zahra; Ramos, Sérgio Filipe Carvalho; Soares, João; Vale, Zita; Gomes, AntonioNowadays, the buildings have an important role in the high demand for electrical energy. Therefore, the energy management of the buildings may have significant influence on reducing the electricity consumption. Moreover, Electric Vehicles (EVs) have been considering as a power storage device in Smart Buildings (SBs) aiming to reduce the cost and consuming energy. Here, an energy management framework is proposed in which by considering the flexibility of the contracted power of each apartment, an optimal charging-discharging scheduled for EVs and Battery Energy Storage System (BESS) is defined over a long time period to minimize the electricity cost of the building. The proposed model is designed by a Mixed Binary Linear Programming formulation (MBLP) that the charging and discharging of EVs as well as BESS in each period is treated as binary decision variables. In order to validate the model, a case study involving three scenarios are considered. The obtained results indicate a 15% reduction in total electricity consumption cost and consumption energy by the grid over one year. Finally, the impact of capacity and charge/discharge rate of BESS on the power cost is analyzed and the optimal size of the BESS for assumed SB in the case study is also reported.
- Data mining techniques for electricity customer characterizationPublication . Ramos, Sérgio Filipe Carvalho; Soares, João; Cembranel, Samuel S.; Tavares, Inês; Foroozandeh, Z.; Vale, Zita; Fernandes, RubipiaraThe liberalization of electricity markets has been resulted in the emergence of new players, increasing the competitiveness in the markets, standing those can provide better services for better prices. The knowledge of energy consumers’ profile has been an important tool to help players to make decisions in the electrical sectors. In this paper, a characterization model of typical load curves for Low Voltage (LV) customers is proposed and evaluated. The identification of consumption patterns is based on clustering analysis. The clustering methodology is based on seven algorithms, partitional and hierarchical. Also, five clustering validity indices are used to identify the best data partition. With the knowledge obtained in clustering analysis, a classification model is used to classify new customers according to their consumption data. The classification model is used to select the correct class for each customer. To make the model simple, each load curve is represented by three indices which represent load curves shape. The methodology used in this work demonstrates to be an effective tool and can be used in most diverse sectors, highlighting the use of knowledge in the optimization of the energy contracting for low voltage customers. The energy consumption data can be constantly updated to improve the model precision, finding estimates that can better represent consumers and their consumption habits.
- Dynamic electricity tariff definition based on market price, consumption and renewable generation patternsPublication . Ribeiro, Catarina; Pinto, Tiago; Faria, Pedro; Ramos, Sérgio Filipe Carvalho; Vale, Zita; Baptista, Jose; Soares, Jono; Navarro-Caceres, Maria; Corchado, Juan ManuelThe increasing use of renewable energy sources and distributed generation brought deep changes in power systems, namely with the operation of competitive electricity markets. With the eminent implementation of micro grids and smart grids, new business models able to cope with the new opportunities are being developed. Virtual Power Players are a new type of player, which allows aggregating a diversity of entities, e.g. generation, storage, electric vehicles, and consumers, to facilitate their participation in the electricity markets and to provide a set of new services promoting generation and consumption efficiency, while improving players' benefits. In order to achieve this objective, it is necessary to define tariff structures that benefit or penalize agents according to their behavior. In this paper a method for determining the tariff structures has been proposed, optimized for different load regimes. Daily dynamic tariff structures were defined and proposed, on an hourly basis, 24 hours day-ahead from the characterization of the typical load profile, the value of the electricity market price and considering the renewable energy production.
- Energy Management in Smart Building by a Multi-Objective Optimization Model and Pascoletti-Serafini Scalarization ApproachPublication . Foroozandeh, Zahra; Ramos, Sérgio Filipe Carvalho; Soares, João; Vale, ZitaGenerally, energy management in smart buildings is formulated by mixed-integer linear programming, with different optimization goals. The most targeted goals are the minimization of the electricity consumption cost, the electricity consumption value from external power grid, and peak load smoothing. All of these objectives are desirable in a smart building, however, in most of the related works, just one of these mentioned goals is considered and investigated. In this work, authors aim to consider two goals via a multi-objective framework. In this regard, a multi-objective mixed-binary linear programming is presented to minimize the total energy consumption cost and peak load in collective residential buildings, considering the scheduling of the charging/discharging process for electric vehicles and battery energy storage system. Then, the Pascoletti-Serafini scalarization approach is used to obtain the Pareto front solutions of the presented multi-objective model. In the final, the performance of the proposed model is analyzed and reported by simulating the model under two different scenarios. The results show that the total consumption cost of the residential building has been reduced 35.56% and the peak load has a 45.52% reduction
- Equipamentos de rede: Equipamentos passivos e ativosPublication . Ramos, Sérgio Filipe CarvalhoO termo redes de computadores está cada vez mais em desuso com a crescente introdução de novas tecnologias e dispositivos, ligadas à internet pública. Todos esses dispositivos não são unicamente compostos por computadores (torres os portáteis) mas cada vez mais por uma grande panóplia de equipamentos, tais como smartphones, sistemas de automação residencial ou industrial entre outros aparelhos eletrónicos. Estes dispositivos são criteriosamente interligados e percorrem um caminho que passa por enlaces de comunicação (cabos, ondas rádio, fibras óticas, etc.) e também por comutadores de pacotes (Switches, Hubs, Routers, etc.). O primeiro é o meio físico responsável pela transmissão em si (equipamentos passivos), enquanto o segundo faz o encaminhamento dos pacotes aos seus destinos (equipamentos ativos). Assim, o presente artigo visa, mesmo que de um modo muito sucinto, efetuar a distinção entre equipamento passivo e ativo, bem como caraterizar alguns dos principais equipamentos e dispositivos que os integram.
- A Flexibility Home Energy Management System to Support Agreggator Requests in Smart GridsPublication . Sousa, Tiago; Lezama, Fernando; Soares, João; Ramos, Sérgio Filipe Carvalho; Vale, ZitaEnergy flexibility will play a key role in the proper functioning of energy systems, introducing a set of benefits to all involved stakeholders and changing the shape of electricity markets as we know them. It is expected that new players with different interests will emerge in this context. Particularly, the aggregators might allow end-users to be aware of their consumption flexibility value, or merely facilitate consumer's participation, for instance through the use of demand response. To this end, a prompt system response allowing the interaction between aggregators and residential users is needed. Therefore, the so-called Home Energy Management System (HEMS) becomes an active tool to communicate end-users with aggregators, performing the necessary changes in the consumption profiles in benefit of all involved parts. In this paper, a model with the objective of achieving a match between the flexibility required by an aggregator and the flexibility offered by residential users through the HEMS capability of shifting specific appliances is proposed. The model is then solved using a well-known swarm intelligence algorithm, the particle swarm optimization (PSO). An illustrative example of how the model is optimized using PSO, re-scheduling appliances to meet a flexibility curve, is presented. After that, a case study with 15 appliances based on real profiles of home devices is solved showing the effectiveness of the proposed approach to procure flexibility.
- Graus de proteção assegurados pelos invólucrosPublication . Gomes, António Augusto Araújo; Ramos, Sérgio Filipe CarvalhoExistem dois tipos de graus de proteção, tendo cada um deles o seu sistema de codificação Código IP e Código IK. Cada um destes códigos encontra se descrito e caraterizado numa norma, que indica também a metodologia de realização dos testes de verificação do código: • Código IP NP EN 60529 (Aplicável a invólucros de tensão estipulada igual ou inferior a 72 5 kV) • Código IK NP EN 50102
- Interruptores (mecânicos) para uso industrial ou instalações semelhantesPublication . Gomes, António Augusto Araújo; Sá, André Fernando Ribeiro de; Ramos, Sérgio Filipe CarvalhoUm interruptor (mecânico) é definido como um aparelho mecânico de conexão capaz de estabelecer, de suportar e de interromper correntes nas condições normais do circuito, incluindo, eventualmente, as condições especificadas de sobrecarga em serviço. É um aparelho que é ainda capaz de suportar, num tempo especificado, correntes nas condições anormais especificadas para o circuito, tais como as resultantes de um curto-circuito.
- ITCALC: Desenho e cálculo de infraestruturas de telecomunicaçõesPublication . Martins, Hélder Nelson Moreira; Ramos, Sérgio Filipe CarvalhoNo início desta década a TELEVÉS lançou o Software para cálculo de redes ITED (Prescrições e especificações técnicas das Infraestruturas de Telecomunicações em Edifícios) e ITUR (Prescrições e especificações técnicas das infraestruturas de telecomunicações em loteamentos, urbanizações e conjuntos de edifícios), o CAST 60 (conforme figura 1), programa vocacionado para o auxílio ao cálculo de instalações de comunicações eletrónicas, que permitia criar redes de: ITED 2Edição, SMATV (Satellite Master Antenna Television) e CATV (Cable Television, ou Community Antenna Television).
- ITED – 3ª edição 2015: manual evolutivo e reconstrutivoPublication . Ramos, Sérgio Filipe CarvalhoAo longo das últimas décadas Portugal tem assistido a um abrandamento na construção civil e, naturalmente, na construção de edificado novo. Porém, subsiste a necessidade de requalificar os edifícios já existentes que serão, indubitavelmente, o grande nicho de negócio nas décadas vindouras. Paralelamente, a legislação e as especificações e prescrições técnicas das diversas instalações específicas, designadamente as Infraestruturas de Telecomunicações em Edifícios (ITED), devem convergir para a harmonização com as Normas Europeias e adaptadas à realidade económica do país. Assim, é com naturalidade que se prevê uma nova edição do Manual ITED (a 3ª Edição) para o próximo ano de 2015 que vise fundamentalmente, a atualização das especificações e prescrições técnicas à realidade tecnológica atual (e futura), à normalização europeia e uma convergência com a real situação económica portuguesa. O presente artigo propõem, de uma forma sucinta, evidenciar as principais alterações decorrentes da proposta do novo enquadramento das Infraestruturas de Telecomunicações em Edifício (ITED) a ser criada pela 3ªEdição do respetivo Manual.