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Electric cars

the Science and technics
 
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electric power Manufacture is easy enough process, and electric motors can serve for the various purposes - from drilling of chinks before maintenance of movement of trains.

The Matter consists of atoms which, in turn, develop from elektricheski the charged particles - protons and elektronov. Still ancient Greeks knew that if poteret amber a fabric slice, it will draw easy subjects, but did not understand the event reason. Actually as a result of a friction there was an electricity.

Usually in any substance there is an equal quantity negatively and positively charged particles. Therefore their electric charges are counterbalanced, and the substance is neutral. However as a result of a friction some elektrony move from one material on another. As consequence, balance of charges is broken: the material which has drawn elektrony, becomes negatively charged, and the material which has given they be positively charged.


the Charged subjects

Terms "Іыхъ=Ёюэ" and "Іыхъ=Ёшёхё=тю" have occurred from the Greek word elektron, meaning " э=рЁі". Though Greeks have taken the important step to a direction of the large opening, the first car, capable to develop an electricity, has been invented only apprx. 1650 in Germany. Otto the background of Gerike has created the simple car including the big sphere from sulphur. At a contact a sphere hand, nasazhennogo on a shaft and rotated by means of the handle, that was charged as a result of a friction. By XIX century many similar frictional generators have been invented.

At the heart of work of other type of the generator the principle of an electrostatic induction - process at which the subject is charged from other charged subject being nearby lay. Such asynchronous generators accumulate the induced charges for high voltage reception. The similar car invented by James Uimsherstom in 1883, still is used in laboratory trials for reception of pressure to 50 000 volt, and sometimes and above.


Powerful electrocars

In 1931 Van-de-Graaf has invented the electrostatic generator of wide practical application. The moving tape from dielektrika transfers a charge gradually increasing to several millions volt to a metal sphere. Generator Van-de-Graafa is used at tests of insulators and other equipment calculated on high pressure, and also in nuclear researches, thus the high voltage serves for dispersal of the charged subnuclear particles.

Though frictional and asynchronous cars could create a high voltage, they did not suit development of a strong direct current. The given problem has been solved in the end of 1790th when the Italian scientist Alessandro Volta has invented the first battery. Subsequently it has been improved that has allowed, since the end of XIX century, to use an electricity for illumination. Though batteries are a convenient and multi-purpose source of the electric power, they gradually are discharged and require replacement or additional charge. The experiments spent in the beginning of XIX century, have led to creation of modern generators.


Ersted and Ampere

In 1819 the Danish professor Hans Ersted has made opening: the electric current flowing on a wire forced to deviate to an arrow of a magnetic compass. So Ersted has opened the electromagnetism phenomenon - the magnetism created by an electricity. In 1821 the French scientist Andre of Amperes has shown the mechanical interaction of currents connected with it: at propuskanii an electric current through a wire which is near to a powerful magnet, wire moving was observed, - and has established the law of this interaction. This principle underlies an electric motor: transformation of electric energy to the mechanical.

Ampere Experiences were extremely interesting, but had no practical application. The wire moved at current occurrence simply a little. But the same year English scientist Michael Faradej has created the car which by means of an electricity provided long movement. The bottom end of the suspended wire was located in a vessel with mercury in which center there was a rod magnet. At battery connection between the top end of a wire and mercury the wire started to rotate round a magnet.


the Electromagnetic induction

the Electromagnetic induction the Open Faradeem the phenomenon of an electromagnetic induction named it "Іыхъ=Ёшёхёъшь тЁрЁхэшхь" has laid down in a basis of a principle of work of modern electric motors. The first electric motor, found practical application, has been invented in 1837 by the American engineer Thomas Davenportom. It used such two engines: for work drilling and derevoobrabatyvajushchego machine tools.

Having studied an electricity as motive power, Faradej has started to search for ways of transformation of mechanical energy to the electric. In 1831 it has shown that moving of a rod magnet near the wire coil caused electrocurrent passage through the measuring device connected to it. Thus the current strength was much more above, than in case of an unary wire.


the Electrical supply

Faradej the first used electromagnetic effect for electricity manufacture. By the end of 1870th there were powerful generators, and in 1881 the first power station in Godalminge (England) has earned. It became also the first-ever hydroelectric power station as the generator was set in motion by a water-mill.

At electric motors and generators much in common, and some cars can carry out functions both. In the simple electric motor the wire coil fastens on a shaft that allows it to rotate freely between poles podkovoobraznogo a constant magnet. The coil plays an electromagnet role, being magnetised at passage through it of an electric current. The iron core being in the coil strengthens created magnetic effect.


direct current Engines

The Electric current from the battery or other source, moving only in one direction, is called as a direct current. If the battery is connected to the coil of the simple electric motor, the coil is magnetised, thus on its opposite ends there are two poles - negative and positive. As opposite poles are mutually drawn, northern and southern poles of the coil aspire, accordingly, to southern and northern poles of a constant magnet. These forces of an attraction force the coil to rotate about the axis, and soon its poles settle down at opposite poles of a constant magnet.

However during this moment the automatic switching device (collector) directs a current to an opposite side. The collector of the simple electric motor of a direct current consists of the copper ring cut half-and-half and fastening (with a lining from dielektrika) on a rotor axis. The coil ends are connected to two halves of a ring. The current passes through the coil and gets on pair coal contacts - the brushes, concerning opposite sides of a collector. At rotor rotation each brush serially co-operates with both parties of the coil.


Automatic switching

Thanks to automatic switching magnetic poles of the coil change on opposite at achievement of poles of a constant magnet. Now they not so heteronymic, and the poles with the same name in relation to the nearest poles of a magnet. As the poles with the same name mutually make a start, the coil continues to rotate, and its poles are drawn to corresponding poles on other party of a magnet.

The Rotating part of the electric car is called as a rotor (or an anchor), and motionless - statorom. The coil block serves In the simple electric motor of a direct current as a rotor, and a constant magnet - statorom.

The electromagnet serves In some engines for creation of a magnetic field instead of a constant magnet. Coils of a wire of such electromagnet are called as an excitation winding.


alternating current Engines

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The Alternating current periodically changes a direction, usually 50 or 60 times a second. Some engines of an alternating current have a rotor, on which current moves through a collector, as in direct current engines. But many engines of this type in general do not have connections with a rotor. Their action is based on an induction principle. Passing through stator the alternating current creates rotating magnetic field as would be in case of rotation of a constant magnet. This moving field forces a current a leak in a direction of windings of a rotor, magnetising it. As a result the rotor rotates, as its poles the magnetic field rotating round a rotor compels to circle. Often the rotor consists of the copper or aluminium cores which ends connect two metal rings. The rotor in gathering is similar to a cage, and such cars name engines with "схышёіхщ ъых=ъющ" or short-circuited engines.


Synchronous engines

In induction (asynchronous) engines the rotor rotates more slowly, than moving round it a magnetic field. In synchronous engines the rotor turns simultaneously with a field. In simple synchronous engines the rotor consists of one or several constant magnets. Their poles are drawn to heteronymic poles of a rotating magnetic field, therefore they rotate with identical speed. Sometimes instead of constant magnets in rotors electromagnets are used, but the work principle remains invariable. In other type of synchronous engines jumps of an alternating current for creation of a magnetic field which poshagovo rotates a rotor with a cogwheel are used.

The Majority of electric motors create a rotary motion. But at some of them windings statora are opened and located on one line thanks to what the magnetic field, moving linearly together with provodnikovym a material is created. Such engines are called as linear asynchronous. They are used for opening of sliding doors, luggage transportation at the airports, in high-speed trains.


Generators

If a rotor of the simple electric motor of a direct current to rotate manually, the engine will work as the generator. In the coil there is an alternating voltage reaching of peak sizes when its poles take place poles of a constant magnet. Then pressure reduces to zero and changes the direction, reaching a maximum when coil poles take place opposite poles of a constant magnet. It is possible to be connected to the coil, having connected the ends of two continuous copper rings (named contact rings), being on a rotor axis. Coal brushes rub about these rings and remove an alternating voltage therefore at connection to an electric chain there is an alternating current. Such generator concerns alternating current generators, i.e. To the electric cars developing an alternating current.


the Dynamo-car

If the collector is used (as in the direct current electric motor), it will constantly change connections between the coil and brushes that interferes with pressure changes in the coil. As a result, instead of an alternating current on brushes the pulsing direct current will proceed. The generators developing a direct current thus, are called as dynamo-cars.

In the majority of dynamo-cars for creation of a necessary magnetic field the electromagnet is used not constant, but. However the electromagnet core is a little magnetised, and it is enough force of its field, that the car has started to develop an electricity at inclusion. Then the part of the developed current passes through a winding of an electromagnet for strengthening of its magnetic field and increase in volume of the electric power.

Some generators of an alternating current (for example, automobile) develop a direct current thanks to the built in rectifiers - to the devices supposing a current of a current only in one direction.

In the majority of generators of an alternating current - from employees for additional charge of accumulators of cars to the huge cars developing an electricity for a power line - coils are available both on a rotor, and on statore, and the rotor creates a magnetic field. Rather the small current passes through excitation windings on a rotor on brushes and contact rings, and stronger developed current is selected directly with statora. It allows to avoid losses of capacity and iskrenija, possible at selection of a strong developed current from a rotor by means of rings and brushes.