Delayed Current Zeros in FPSO Offshore Units

It is well established that when short-circuit occurs close to generators’ terminals, the instantaneous value of the fault current through the circuit-breaker may not reach zero amperes for some considerable time, so called delayed current zero phenomenon. Therefore circuit-breakers may not be suitable to clear the fault under this condition. Today’s floating production, storage and offloading (FPSO) units are very large in terms of installed generation capacity, in the range of 100 MVA, and in terms of number of medium voltage motors, many of them connected directly to the generation voltage level. This leads to a very favorable condition for the occurrence of delayed currents zeros in FPSO’s electrical power systems.

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On-line optimization of COPENE´s thermoelectric system

This paper presents practical aspects of COPENE´s thermoelectric system optimizator implementation, which has the task of determining operating conditions that minimize fuel and electric power costs. The focus is on system modeling, data base and simulation and on the interface with the supervisory system.

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Parallel Operation of Self-Generating Industrial Systems and Utility Grid: Technical Aspects of Systems Integration and Future Perspectives

This paper treats technical aspects of parallel operation of self-generating industrial systems and utility grid. The focus is on typical protection and operation philosophies nowadays adopted by cogenerating industries based on studies performed by FIGENER in the last two years. The work is developed by way of identifying which points could be improved and could permit a better utility and self-generating industries integration looking toward a general improvement of electric power quality and energy efficiency.

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Sistemas de Proteção Digitais: Mudanças no Projeto, Instalação e Operação de Sistemas Elétricos

Apesar de os sistemas de proteção, medição e controle digitais já serem empregados em larga escala em sistemas elétricos de potência, muitos dos critérios empregados nos sistemas elétricos ainda são os mesmos do tempo dos equipamentos eletromecânicos, não possibilitando o aproveitamento de todos os benefícios que este tipo de equipamento pode trazer ao sistema elétrico como um todo.

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