After the first successful experiments with electricity the engineers and inventors thought of whether it is possible to create the engine which is put in action by this perspective energy. As a result the electric motor was born. This device was constantly improved, its power and profitability increased, but the principle of operation of the electric motor almost did not undergo changes.
Device of the electric motor and principle of its action
The electric motor is called the technical system in which energy of electricity is transformed to energy of mechanical type. Operation of such engine is constructed on the phenomenon of electromagnetic induction. The device of an electric motor assumes existence in it of a motionless element – the stator and also the mobile part called an anchor or the rotor.
In the traditional electric motor the stator is an external part of a design. This element forms motionless magnetic field. The mobile rotor is placed in the stator. Permanent magnets, the core with windings, the collector and brushes are its part. Electric currents proceed through the winding consisting usually of a set of rounds of a copper wire.
During the operation of the electric motor connected to a power source there is an interaction of fields of the stator and rotor. There is a rotating moment. It also sets the electric motor rotor in motion. Thus, the electric power given on windings is transformed to energy of rotary motion. Rotation of a shaft of the electric motor is transferred to working body of a technical system which structure switched on the engine.
Features of the electric motor
The electric motor is one of types of electrical machines to which also generators belong. Thanks to property of reversibility the electric motor is in case of need capable to perform functions of the generator. Also the return transition is possible. But most often each electrical machine is designed only for performance of quite certain function. In other words, the electric motor will work most effectively in this quality. The transformation of the electric power to energy of mechanical rotation happening in the engine is by all means connected with power losses. Heating of conductors, magnetization of cores, the harmful friction force arising even when using bearings becomes the reasons of this phenomenon. The efficiency of an electric motor is influenced even by friction of moving parts about air. And still in the efficiency most perfect engines it is rather high and can reach 90%. Having a number of indisputable advantages, the engines working at electricity became widespread extremely in the industry and in life. The main advantage of such engine consists in convenience of its use and high operational characteristics. The electric motor does not give harmful emissions in the atmosphere therefore its application in cars is very perspective.