Theory of Alternating Current Machinery by Alexander Langsdorf: A Classic Textbook on Electric Machines
Theory of Alternating Current Machinery is a textbook written by Alexander S. Langsdorf, a professor of electrical engineering at Washington University in St. Louis. The book was first published in 1937 and has been revised and updated several times since then. The latest edition was published in 2001 by Tata McGraw-Hill.
The book covers the principles and applications of electric machines that operate on alternating current, such as transformers, induction motors, synchronous generators and motors, and special machines. The book also includes topics such as polyphase circuits, magnetic circuits, vector analysis, harmonics, and power systems. The book is known for its clear and rigorous presentation of the theory, as well as its numerous examples and problems.
Theory of Alternating Current Machinery is widely regarded as a classic and authoritative reference in the field of electric machines. It has been used by generations of students and engineers who want to learn and master the fundamentals and advanced aspects of alternating current machinery. The book is also a valuable source of information for researchers and practitioners who are interested in the design, analysis, and operation of electric machines.
The book can be found online at Google Books[^1^] [^2^] or at Open Library[^3^].
Alternating current machinery has a wide range of applications in various fields of engineering and technology. Some of the common applications of alternating current machinery are:
AC motors: AC motors are electric machines that convert alternating current into mechanical rotation. AC motors are used for various purposes such as fans, pumps, compressors, conveyors, elevators, cranes, etc. AC motors can be classified into two types: synchronous motors and induction motors. Synchronous motors operate at a constant speed that is proportional to the frequency of the supply voltage. Induction motors operate at a speed that is slightly less than the synchronous speed and depend on the load and slip. Induction motors are more widely used than synchronous motors because they are simpler, cheaper, more reliable and more efficient[^1^].
AC generators: AC generators are electric machines that convert mechanical rotation into alternating current. AC generators are used for generating electric power in power plants, hydroelectric dams, wind turbines, etc. AC generators can also be classified into two types: synchronous generators and induction generators. Synchronous generators produce a constant frequency and voltage output that is synchronized with the grid. Induction generators produce a variable frequency and voltage output that depends on the speed and load. Induction generators are more suitable for renewable energy sources such as wind and water[^2^].
Transformers: Transformers are devices that transfer electric power from one alternating current circuit to another by using electromagnetic induction. Transformers can either increase or decrease the voltage and current levels depending on the number of turns in the primary and secondary coils. Transformers are used for various purposes such as transmission, distribution, isolation, impedance matching, etc. Transformers can also be classified into two types: step-up transformers and step-down transformers. Step-up transformers increase the voltage and decrease the current levels while step-down transformers decrease the voltage and increase the current levels[^3^].
Alternating current machinery has many advantages over direct current machinery such as higher efficiency, lower power loss, easier voltage conversion, safer operation, etc. Alternating current machinery is also easier to design, manufacture and maintain than direct current machinery[^4^]. a474f39169