ABSTRACT
A major application of electric energy is in its conversion to mechanical energy. Electromagnetic, or “EM” devices designed for this purpose are commonly called “motors.” Three-phase alternating current synchronous motors are not amenable to frequent starting and stopping, but are ideal for medium and high power applications which run at essentially fixed speeds. Actually the machine is the central component of an integrated system consisting of the source, controller, motor, and load. For specialized applications, the system may be, and frequently is, designed as a integrated whole. Flow of energy through the system is from left to right, or from electrical source to mechanical load. Consider positive speed as “forward,” meaning rotation in the “normal” direction, which should be obvious in a specific application. The design of a properly engineered motor-controller system for a particular application requires access to several technical resources, including standards, the technical literature, manufacturers’ publications, textbooks, and handbooks.
