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Circuit breakers serve to connect and disconnect electric circuits under any operation conditions. Improving circuit breaker reliability is important for the correct operation of electric power systems. In this paper, we use one of the existing methods for the analysis of reliability in devices and components according to Norsok Standard Z-013. The criticality level of the circuit breakers in a substation is determined from the quantity of operational failures, the power flow through the circuit breaker, and the circuit breaker incidence in the electric power system stability. The paper includes the analysis of historical data over a five-year period and shows the results of the obtained mathematical expression. These results will allow developing maintenance strategies directed towards the most critical circuit breakers to improve their reliability. [ABSTRACT FROM AUTHOR]

This paper presents a framework for minimizing the average interruption frequency in radial Distribution Systems with uniformly distributed loads. Here, the position of the reclosers has been modeled using a linear approximation. The objective of this paper is to minimize the average interruption frequency per installed power. According to the current electric regulation in Chile, this index is the metric used to regulate and classify the performance of utilities. In the analysis a novel concept of Distance Factor between the main feeder and a branch feeder was introduced. This concept can be utilized as a theoretical limit for the number of switches to install on the main feeder. In addition, based upon the service history of the line, the distance factor determines if a certain line must be economically assessed like a new feeder so that the aforementioned performance index of average interruption frequency per installed power is minimized. [ABSTRACT FROM AUTHOR]

In this paper, we study facility location problem under many optimization criteria, as minimize the probability of failure and the supply chain total cost. We incorporate account transportation costs, consolidation center cost and reliability of the supply chain. The approach is to design robust supply chains that will be able to absorb negative impacts caused by disruptive events, such as hurricanes, twisters, earthquakes, strikes, accidents, among others. We provide a nonlinear integer-programming model that determines the optimal location of facilities under the criteria of cost and reliability. The proposed model was validated with data obtained from a supply chain of agribusiness sector of Atlantic department in Colombia. The numerical results show an improve of 9.5% in the reliability with an increase of 9.8% on transportation total cost of the supply chain. However, in the proposed model, the companies would not have to incur adequacy costs of consolidation centers, given that current facilities have the capacity to become consolidation center without incurring on significant costs [ABSTRACT FROM AUTHOR]

This article describes two new methodologies for optimal distribution system planning considering automatic reclosers to improve reliability indices. The first methodology proposed in this paper employs a two-stage cascade strategy to solve the problem. In the first stage a mono-objective Tabu Search (TS) algorithm is used to find the optimal distribution system topology. The installation cost of new elements, increasing capacity on existing elements and operational costs associated with technical losses are considered. In the second stage a Non-Dominated Sorting Genetic Algorithm known as NSGA II is employed, considering the optimal distribution system topology found by the first stage, and thus, solving the problem of optimal location of automatic reclosers in distribution systems. The non-supplied energy level of the network and installation cost of reclosers are considered as objective functions; and the min-max criterion to select a point on the optimal Pareto front is used. In the second methodology, a master-slave based optimization algorithm is used to find the best network topology including the associated to automatic reclosers. Master algorithm is a TS algorithm which is responsible to direct the optimization process through solution space, whereby, for each neighbor generated, the slave algorithm NSGA II is applied and min-max criterion is used to determine a configuration of reclosers for actual network topology. The proposed methodologies are applied on three-phase version of IEEE 34 nodes test feeder, with high quality results. [ABSTRACT FROM AUTHOR]

This paper has the goal to propose a procedure to design an instrument base on interview to assess the state of the management maintenance in the bio-products plants. On describe the methodology to do the validation thought by test of validation and reliability. This instrument, allows knowing with 90,8 % of reliability based on the information the condition of maintenance in this plants. The application in the case study showed the rightness of this instrument. The assessments of this plant produce as a result the bad condition of the management maintenance and the possibility of improvement. [ABSTRACT FROM AUTHOR]

This paper presents a reliability evaluation of the Chilean SING* by means of an analytical and probabilistic method for the enumeration of states, which permits to determine the unavailability index and the associated overcharge factor. This evaluation allows a comparative analysis between the unavailability index and the associated overcharge factor, the CNE**, provides in its technical reports of local the nodal price. Hereby, the proposed results suggest a solution for continuous observations made by SING electric companies in the technical reports of nodal price, with respect to the criteria used for modeling and determining the unavailability of transmition and associated overcharge factor. The reliability evaluation is made considering generation and transmission facilities. * SING: Northern Interconnected System: Transmission system of high voltage electricity in northern Chile. ** CNE: National Energy Commission: Chilean government agency that oversees the transmission systems of electric power. [ABSTRACT FROM AUTHOR]

This paper presents a reliability evaluation of the Chilean SING* by means of an analytical and probabilistic method for the enumeration of states, which permits to determine the unavailability index and the associated overcharge factor. This evaluation allows a comparative analysis between the unavailability index and the associated overcharge factor, the CNE**, provides in its technical reports of local the nodal price. Hereby, the proposed results suggest a solution for continuous observations made by SING electric companies in the technical reports of nodal price, with respect to the criteria used for modeling and determining the unavailability of transmition and associated overcharge factor. The reliability evaluation is made considering generation and transmission facilities. * SING: Northern Interconnected System: Transmission system of high voltage electricity in northern Chile. ** CNE: National Energy Commission: Chilean government agency that oversees the transmission systems of electric power. [ABSTRACT FROM AUTHOR]