API Standard 546-a new purchase specification for large synchronous motors and generators

API Standard 546, Form-Wound Brushless Synchronous Motors, is a purchase specification for synchronous motors and generators. Background information on the creation of the standard is given. An overview is provided of the major electrical and mechanical design features, accessories, and testing requirements. The users' and suppliers' views on the need for the standard are presented. Applications of various synchronous machine constructions are summarized. Contributions of the standard to reliability, particularly in the areas of mechanical vibration and rotor dynamics, are emphasized.<>