Backfilling the sinewave. A dynamic voltage restorer case study

Backfilling the sinewave is an application for electrical energy storage that would have been unheard of 10 years ago. But now the importance of supply quality and the requirement for solutions has never been greater. The problem is voltage dips (sags), or disturbances, wreaking havoc with equipment that is sensitive to imperfections in the sinewave. The dynamic voltage restorer is a solution to these problems, and this article looks at its application, by ScottishPower and Caledonian Paper to solve power quality problems at Caledonian Paper's manufacturing plant in Ayrshire, UK.