About Electrical Machines and Transformers

Electric machines are the study of electric motors and electric generators. Electric machine is synonymous with electric motor or electric generator, all of which are electromechanical energy converters: converting electricity to mechanical power (i.e., electric motor) or mechanical power to electricity (i.e., electric generator). The movement involved in the mechanical power can be rotating or linear. The electrical machines and transformers holds the topics such as AC motor and DC motor, AC Generator and DC generator, Power and Distribution Transformers, Step up and Step down Transformer. Although transformers do not contain any moving parts they are also included in the family of electric machines because they utilise electromagnetic phenomena. Electric machines (i.e., electric motors) consume approximately 60 percent of all electricity produced. Electric machines (i.e., electric generators) produce virtually all electricity consumed. Electric machines have become so ubiquitous that they are virtually overlooked as an integral component of the entire electricity infrastructure. Developing ever more efficient electric machine technology and influencing their use are crucial to any global conservation, green energy, or alternative energy strategy. A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Electromagnetic induction produces an electromotive force across a conductor which is exposed to time varying magnetic fields. Commonly, transformers are used to increase or decrease the voltages of alternating current in electric power applications. A varying current in the transformers primary winding creates a varying magnetic flux in the transformer core and a varying magnetic field impinging on the transformers secondary winding. This varying magnetic field at the secondary winding induces a varying electromotive force (EMF) or voltage in the secondary winding due to electromagnetic induction. By Faradays Law in conjunction with high magnetic permeability core properties, transformers can thus be designed to efficiently change AC voltages from one voltage level to another within power networks.