Harmonic filters for industrial applications. Technology procurement report from the Swedish National Energy Administration

The Harmonic Filter Project was started in June 1998 and conducted as technology procurement directed and financed by the Swedish National Energy Administration. The project was supported by a purchase group consisting of the following companies: Fagersta Stainless, LKAB, AB Sandvik Steel, Fundia Special Bar, SSAB, Vasakronan, Scania Partner, MoDo Paper, Stora Paperboard AB and Korsnas. The purpose of the project was to select a system capable to meet industries´ needs of harmonic filtering and reactive power compensation. The purchase group formulated the requirements and specifications for the product which became the basis for a "competition" among manufacturers throughout the world. The specification of user´s requirements called for a system suitable to serve dual purposes: reactive power regulation and harmonic filtering, located centrally on the low voltage side of distribution transformers. The reactive power compensation should be dynamic, regulated continuously or in steps, and extendible. The harmonic filter should be of active type or combination of active and passive filters. As a part of the Framework Agreement with the winner, two pilot series filters were installed and tested-the first one at AB Sandvik Steel and the second one at Stora Enso, Gruvon. Both installations have been subjected to extensive verification tests. The results of the tests proved that the new filter technology has the potential to solve most of the harmonic related problems in industrial low voltage networks.