ABSTRACT
It is necessary to change voltage levels efficiently, when processing bulk electrical energy. For example, it is convenient, economical, and safe to operate household appliances such as television sets and microwave ovens at a low voltage level (e.g. 120 V). However, it is not practical to transport any significant amount of power (over 10 kW, for example) more than a few dozen feet at that voltage because of the corresponding high current and associated I2R winding loss. What is needed is a highly efficient and reliable device to convert electric power from one voltage level into another. The power transformer is just such a device. Strictly speaking, it fails to qualify as an electromagnetic (EM) machine, because it has no moving parts, and hence cannot perform the requisite electrical to mechanical energy conversion process. However, it performs electric-to-magnetic-to-electric energy conversion. This property, plus the fact that the power transformer is an important component found in almost all power systems, merits our study of this important device.
