Overview of the Development and Application of Electrical Machines

Abstract

This chapter presents a brief historical overview of the development of miniature electrical machine technology, which is given in the form of examples mostly motivated by the demands of military uses in particular around the time of World War II. This technology was replaced by analog computer electronics in the form of cascaded differentiators, integrators, and summing operational amplifiers which in turn were replaced soon thereafter by digital transistor electronics which ended the use of electro machine devices as computational modules for use in artillery missile guidance and on-board navigational computer control systems. Historically speaking, a substantial amount of exploration in the development and implementation of miniature electrical machine technology of both sin-cos transformers and servo motors for missile guidance computer tracking systems and aircraft control was made by the German firm Askania Werke. This firm developed a type of electrical machine tracking computer system to solve missile targeting problems using vectorial properties of AC electrical machines such as sin-cos transformers (see Chapter 2), tachogenerators, and AC and DC servomotors in closed-loop control.