Steady-State Three-Phase Induction Motors

Abstract

For nearly a century and until recent years industrial induction motors were designed to be fed exclusively through fixed frequency and magnitude main voltage lines. Indeed, steady-state operation has long been the principal activity of engineers involved in the study and use of induction motors. Transient phenomena were infrequent events encountered during starting or under faulty conditions. The main concern was to make sure that the rather rudimentary auxiliary equipment used in conjunction with induction motors was capable of limiting currents during start-up and of breaking the circuit under faulty conditions.