Modern electric drives are used extensively in industrial applications to perform a mechanical maneuver for a given load. In addition, they have other widespread applications, ranging from robots to automobiles to aircraft. Recent advances in the design of electric drives have resulted in low-cost, lightweight, reliable motors. Moreover, advances in power electronics have resulted in a level of performance that was not possible a few years ago. For example, induction and synchronous motors were never used in variable-speed applications until variable frequency and rapid switching were developed. In addition, owing to advances in power electronics, several designs of electric motors are now available.The essential goal of this book is to offer simple and concentrated scientific material about the principles of electric drives equipped with enough applied examples, and tutorial problems for those students and engineers who are interested with electric drive science.