In this paper, a methodology is developed for reliability evaluation of electromechanical systems. The method is applicable in early design phase where there is only limited failure data available. When experimental failure data is scarce, generic failure data are searched from some related reliability data banks. In this method, Reliability Block Diagrams (RBD) is used for modeling the system ...

The paper generalizes a preventive maintenance optimization problem to multi-state systems, which have a range of performance levels. Multi-state system reliability is defined as the ability to satisfy given demand. The reliability of system elements is characterized by their hazard functions. The possible preventive maintenance actions are characterized by their ability to affect the effective...

in order to perform preventive maintenance (pm), two approaches have evolved in the literature. the traditional approach is based on the use of statistical and reliability analysis of equipment failure. under statistical-reliability (s-r)-based pm, the objective of achieving the minimum total cost is pursued by establishing fixed pm intervals, which are statistically optimal, at which to replac...

Maintaining civil aircraft air-worthiness requires the reliability of a complex, socio-technic system. This system's reliability is dependent on the reliability of its components (i.e, equipment, inspectors, the physical environment), and on how reliably these components interact. Error is the measurement counterpart of reliability, and most, if not all, errors can be classified at some stages ...

The assurance of power quality depends on factors which influence the performances of the availability: the reliability and its support – the maintenance. This paper deals with the interactions between the indicators of reliability, maintenance, availability and with the methods for the calculation of the reliability indicators. For an overhead line of 110 kV the characteristics of the reliabil...

This article deals with the assessment of the reliability of sensitive equipment due to voltage sags. The most frequent problems of power quality are voltage sags. Equipment that cannot withstand short-term voltage sag is defined as sensitive device. Sensitivity of such equipment can be described by the voltage–tolerance curves. A device (generator) to generate voltage sags (also interruptions)...

The first part of this paper will attempt to point out the principal difficulties inherent to the necessary collection and validation of the needed failure data. The second part will present a survey of the reliability methods and tools presently used at EDF (Électricité de France) to determine reliability parameters and their evolution with age. The conclusion will focus on some priority field...

In planning studies, the conventional approach for steady state contingency analysis is to test all contingencies sequentially for evaluating system performance and reliability. This analysis consists of simulating outages of one or more generating units and transmission lines to study their effects on bus voltage, generator MVAR outputs and line power flows. But new challenges and uncertaintie...

The Ballistic Mis sile Defense System (BMDS) is a phased arrangement of equipment that is designed to engage a limited number of ballistic missiles launched against the United States and her allies. A phased system is one that changes its characteristics over time. Although a system does not modify its characteristics within a phase, when the system departs one phase and enters another, the sys...

OBJECTIVE Examine thermocouple model uncertainty (reliability+validity). DESIGN First, a 3x3 repeated measures design with independent variables electrothermometers and thermocouple model. Second, a 1x3 repeated measures design with independent variable subprobe. INTERVENTION Three electrothermometers, 3 thermocouple models, a multi-sensor probe and a mercury thermometer measured a stable w...