These notes were written to serve as an aid for students of Higher Education Institutions. They are also addressed to anyone studying the operation of Electric Machines (under steady-state conditions).

Initially, the general operation of electric machines is examined, where the necessary knowledge from electrical circuits is provided to facilitate the reader in the following sections. A very thorough study of section 1.4 is recommended, where the energy problems with alternating currents are discussed. It is also suggested that the reader review the chapters on sinusoidal steady-state and three-phase circuits (mainly basic concepts) found in my book titled 'ELECTRICAL CIRCUITS'.

In the following chapters, each type of electric machine is examined separately: Direct Current, Synchronous, Asynchronous, Transformers. After describing the fundamental principles of operation in each case, a sufficient number of applications under steady-state conditions is provided. We hope that the reader will be significantly aided in this fundamental subject of Technical Sciences. Any constructive observation or suggestion will be appreciated.

[Excerpt from the preface]