This is the third Russian edition of “Automation in Electrical Power Systems" which covers design and operation of automatic control devices intended to prevent and clear faults in electrical power systems and restore power to the loads in the event of breakdown thus assuring continuity of the supply.The reliable and unfailing operation of such devices has been ensured through the research and development effort put into automatic power control systems. The book discusses automatic control in conjunction with protective relaying, since the required reliability and economy of power system operation can be achieved through the combined action of both groups of equipment, each cate­ ring for specific aspects in functioning of loads and generating sources.The wide use of automatic control systems adds to the reliability, stability and economy of power supply systems and takes some burden from attending personnel.The book is designed as a study guide for students of power engineering secondary schools. It may also interest engineers concerned with the operation, installation and design of protective relaying and automatic devices used in electric power stations and networks.