Parallel distribution transformer loss reductions: A proposed method and experimental validation

► An universal method for parallel transformers losses reduction is proposed. ► The method is useful independently of the transformer efficiency class. ► It can be implemented in the existing control systems with a low cost. ► Allows obtaining energy savings of up to 41% on the initial losses. ► The proposed method reduces losses throughout the life cycle in new or existing installations. Transformers in electrical distribution systems for buildings and industries are set up to ensure the continuity of supply. Modern distribution transformers are reaching increasingly higher levels of energy efficiency but contribute to between 16% and 40% of the energy losses associated with electrical distribution systems. This paper examines and proposes a method to reduce losses in transformation systems and thus to reduce the associated emission of greenhouse gases (GHGs). This paper proposes a method of system optimization for transformers in parallel, called Parallel Losses Optimization (PLO), and is applicable to existing or future facilities and is adaptable to any type of transformer system. The method has been validated in 12 real facilities of different power and efficiency levels. Reductions in the losses of the studied transformers were up to 41% with respect to the initial losses. This demonstrates the beneficial operation of the PLO method proposed in this paper in a wide range of existing transformers or for future installations. The research has obtained patent pending status P201101267 in Spain.