The textbook "Asynchronous and Synchronous Electric Motors in Transitional Modes" offers a comprehensive analysis of methods to improve the reliability of large asynchronous and synchronous electric motors. It addresses the rapid switching of power supply to a backup source during short circuits and voltage drops. The authors have developed mathematical models for multi-machine power supply systems that include both motors and protection and automation devices. The book analyzes the transitional processes in the described operating modes and defines conditions that exclude unsynchronized voltage supply to motors from the backup source. Additionally, it outlines requirements for automation devices and switching equipment. The developed algorithms and microprocessor-based devices for rapid power switching are also discussed, including the results of their tests. Finally, recommendations for the application of fast-acting AVR devices in electrical systems with motor loads are provided.