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This paper describes the development of a channel and inventory system (CIS) for power system telecommunications. The system is novel, since no other similar systems have been found. The system is based on a software shell, originally aimed for the process industry, but here developed for telecommunication purposes. The system is in full operation at Swedish National Grid and it has been accepted on a wide scale. This paper highlights the approach for using a supplier based on rapid prototyping. The solution relies on an object-oriented structure, where a worldwide web interface generates adequate user information, which is in- valuable for fault location, fault handling, and telecommunication planning. The CIS possesses several flexible properties, which can be expanded and further developed. [ABSTRACT FROM AUTHOR]

Power-quality voltage and current transient waveform data have been explored rather extensively as the primary input data in predictive maintenance, automatic root-cause analysis, and evaluating system performance to indicate potential problems. Unfortunately, very few efforts have been directed toward making use of the voluminous steady-state data collected alongside waveform data. Therefore, this paper proposes to use steady-state data, particularly, rms voltage data to detect abnormal trend behavior that may be indicative of a problem. Specifically, this paper develops a statistical analysis algorithm based on the well-known statistical process control methods for assessing feeder voltage regulation performance. The assessment results can be used to indicate potential regulator problems as well. The efficacy of the method is demonstrated by applications to two sets of actual rms voltage data. [ABSTRACT FROM AUTHOR]

This paper investigates the factors that influence the outcome of financial-loss analysis in voltage sag studies. Focusing on industrial processes, this paper considers the effects of voltage sag profile estimation, plant-load profile modelling, and process cycle modelling on the financial risk associated with process failure. Based on voltage sag monitoring records, sag profile is probabilistically modeled for the estimation of future sag characteristic. Variations in financial risk due to varying process activities in different stages of a process (process cycle) and load profile are also investigated. The effects of the individual factors are analyzed through Monte Carlo simulation. The stochastic net present value method is introduced as a financial analysis tool. [ABSTRACT FROM AUTHOR]

This paper proposes methodologies for modeling and assessment of equipment and industrial processes susceptibility to voltage sags and short interruptions. Voltage sag severity indices are proposed that translate physical disturbance events into expected equipment behavior, allowing fast identification of possible process failure. Based on these indices, probabilistic and fuzzy-based methodologies are developed to provide realistic equipment representation and to incorporate flexibility for customized process modeling. Extensive simulations showed that the proposed models and methodologies yield greater accuracy in assessments compared to conventional approaches. [ABSTRACT FROM AUTHOR]

Information about the interruption probability of sensitive industrial processes is important for devising mitigation strategies against voltage sags. However, the existing method for assessing interruption probability is less practical, owing to the difficulty in collecting technical information and data from industrial users. This study proposes a low-data-dependence assessment method for the interruption probability of an industrial process. First, it establishes a general assessment model for the tripping probability of sensitive equipment. Second, it proposes a parameter estimation method to determine the probability density function of the voltage tolerance curve of sensitive equipment in the uncertainty region, according to the equipment trip information recorded by the user. This improves the accuracy of the assessment. Third, this study establishes the logic function expression form of the industrial process structure to describe the relationship between the process interruption probability and the equipment tripping probability. Finally, it proposes a solution method for the process interruption probability based on a heuristic search algorithm, which overcomes the problem of technological process information acquisition, such as the logical relationship among various equipment in the industrial process. The rationality and applicability of the proposed method are verified through a case study. [ABSTRACT FROM AUTHOR]