ABSTRACT
A transformer must perform certain functions such as transforming power from one voltage level to another without overheating or without damaging itself when certain abnormal events occur, such as lightning strikes or short circuits. Moreover, it must have a reasonable lifetime (> 20 years) if operated under rated conditions. Satisfying these basic requirements still leaves a wide latitude in possible designs. A transformer manufacturer will therefore find it in its best economic interest to choose, within the limitations imposed by the constraints, that combination of design parameters which results in the lowest cost unit. To the extent that the costs and constraints can be expressed analytically in terms of the design variables, the mathematical theory of optimization with constraints can be applied to this problem.
