A systematic approach for evaluating economic impact of voltage dips

摘要

Power quality is known to be as much an economical issue as a technical challenge. Voltage dip, one of the most prevailing power quality ailments, is known to cause wide-ranging disruptions with economic loses running into hundreds of thousands of dollars. This impact is likely to worsen as many modern electrical apparatus are increasingly relying on semiconductor devices that are vulnerable to voltage dips. Although there exists measures to mitigate against voltage dips but they can be costly and in many cases, it has been difficult to justify their investments. It is therefore imperative to evaluate the economic costs of such disruptions so that their severity can be fully comprehended and correction measures justified. This paper proposes a systematic approach for evaluating this cost in a manufacturing facility setting. It adopts the fault tree analysis to represent the relationship between devices that are vulnerable to voltage dips and processes that have high economical consequences if they are disrupted. The method considers the system performance, device tolerances, effect of device failures on manufacturing process and the corresponding economic losses. This evaluation allows the importance of individual devices to be assessed so that efforts can be concentrated on those financially more rewarding measures.