TY JOUR TI Improving Operational Efficiency Transformers Used in Commercial Power Systems KW demand factor KW transfer performance factor KW capacity losses KW efficiency improvement of power transformers´ exploitation JO Actual directions of scientific researches of the XXI century: theory and practice AU Gracheva, E.. AU Mukhametzyanova, A.. PY 2014 IS 2 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov