Functional definition and classification of the power transformer

The existing power transformer definition excludes the possibility of fulfilling the same functions as described in the definition by making use of other technologies. Most power transformers today are manufactured from conventional materials and are covered by the current approach to standards, but exceptions might be a source of trouble. New regulations are coming into force around the world to improve power transformer performance or its impact on the environment or safety. Such regulations are based on the existing definitions of power transformers under IEEE and IEC, and consequently, emerging technologies not fitting the definition would fall through the cracks. This could distort the market, create unfair competition, and reduce the regulations’ impact. The aim is to propose an adapted definition of the power transformer based exclusively on its functionality. Likewise, a functional power transformer classification based solely on performance and independent from the applied technology is needed. Such classification characterises power transformers based on three categories: rating, technology, and application. Technical standards and legislative documents on power transformers differentiate their requirements based on this classification. A functional classification based solely on performance and independent from the applied technology is needed to avoid hampering the development of new technological solutions.