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The regulation in the public electric energy distribution service considers quality and continuity indicators, presented in Module 8 of the Electric Energy Distribution Procedures in the National Electric System (PRODIST), established by the National Electric Energy Agency (ANEEL). Collective continuity indicators are defined for measuring the distribution quality services, such as: Equivalent Interruption Duration per Consumer Unit (DEC) and Equivalent Interruption Frequency per Consumer Unit (FEC). Also, there are several individual indicators of continuity that deal with the single consumer unit interruption, such as: duration (DIC), frequency (FIC), maximum duration (DMIC) and on a critical day (DICRI).Each of these individual indicators has a stablished limit value, which, if exceeded, results in financial compensation by the distributor (utility) directly to the consumer units. In this way, this paper presents a methodology applied in an algorithm developed using the Matlab software with the purpose of analyzing these indicators impacts along with their financial compensation for modified configuration of the current sets of consumer units of an energy utility. This configuration change is based on the contiguity criteria, which appear in Module 8 of PRODIST. For the development and application of the methodology, initially each substation is considered as a unit of consumers combined. The new proposed configuration achieved a reduction of around 1% in the total amount of financial compensation paid by the utility between the years of 2017 to 2020. This compensation refers to the monthly period, for the DIC, FIC and DMIC indicators. Meaning there is a possibility of future gains by carrying out a reconfiguration of sets without the requiring investment in the grid system.Resumo: A regulação no serviço público de distribuição de energia elétrica considera indicadores de qualidade e continuidade, constantes no Módulo 8 dos Procedimentos de Distribuição de Energia Elétrica no Sistema Elétrico Nacional (PRODIST), estabelecidos pela Agência Nacional de Energia Elétrica (ANEEL). Particularmente quanto à qualidade do serviço são definidos os indicadores de continuidade coletivos, Duração Equivalente de Interrupção por Unidade Consumidora (DEC) e Frequência Equivalente de Interrupção por Unidade Consumidora (FEC), além dos indicadores de continuidade individuais que tratam sobre a interrupção por unidade consumidora, quanto à duração (DIC), frequência (FIC), duração máxima (DMIC) e ocorrida em dia crítico (DICRI). Cada um destes indicadores individuais tem um valor estabelecido como limite, que se caso ultrapassado, incide em pagamento de compensação financeira pela distribuidora diretamente às unidades consumidoras. Dessa forma, este trabalho apresenta uma metodologia, aplicada em um algoritmo desenvolvido com o software Matlab, para análise dos impactos nos indicadores e compensações financeiras com mudança de configuração dos atuais conjuntos de unidades consumidoras de uma concessionária. Essa alteração de conf...

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Nickel alloys such as Inconel 718 have been widely used in the aerospace, oil & gas and chemical industries, due to their excellent properties that combine high creep resistance and high mechanical strength, fatigue and corrosion. However, these properties make these alloys extremely difficult to machine due to high heat generation during material removal, occurring a quick cutting tool wear that produces a detrimental effect on the surface integrity, reducing fatigue life of machined component and low productivity. For these reason, the aim of this work was the evaluation of the influences of cutting parameters on the surface integrity of the Inconel 718 turned under cryogenic condition using liquid nitrogen (LN2) in high cutting speed. The whisker reinforced ceramic tool was used for resisting at high speed cutting, associated with aspects of surface integrity in terms of roughness Ra, residual stresses, microhardness and white layer as well as cutting forces. Central composite design was chosen as factorial planning for the independent variables as cutting speed, feed rate and depth of cut to carry out of the experiments. Cryogenic cooling resulted in average cutting force of 267 N, where penetration force was higher. The roughness Ra was of 0.52 μm, influenced by feed rate and depth of cut. Regarding to residual stresses measurement, higher tensile residual stresses with LN2 and dry conditions were 1394 MPa and 1237 MPa in the circumferential direction respectively, influenced by depth of cut. Small microhardness changes occurred until 0.3 mm from beneath machine surface and presence of white layer was not noticed. Although tensile residual stresses were slightly higher using LN2 in relation to dry machining on surface, LN2 resulted in higher compressive residual stresses on subsurface, which can improve fatigue life of machined components in high cutting speed. The results showed that lower cutting parameters tend to present the best results regarding the aspects of cutting force and surface integrity.