Where an electric motor is used - examples. Application of electric motors

The electric motor converts electricity into a mechanical one. It consists of a stator (or armature) and a rotor. Such a device has become very widespread in all spheres of life. Thanks to electric motors it was possible to replace in many areas the work of man with the work of a machine. Let's consider various types of motors and find out where the electric motors are used (see examples below).

Principle of operation

The electric motor is arranged quite simply. It is based on the principle of electromagnetic induction. The installation includes a fixed part - a stator mounted in alternating current motors of a synchronous and asynchronous type or inductor (for a DC motor), as well as a rotor, ie a moving part for synchronous and asynchronous types, or an armature for DC devices.

Rotors can be short-circuited (like a squirrel cage) and phase with a winding (a system of contact rings). Cases where the last type of motor is used represent devices of an asynchronous type for current reduction and speed control.

The moving part in the DC device or operating on this principle in a universal motor is called an anchor. A universal motor is a direct current motor that has a series of excitation, that is, a series connection of the armature and winding. There is no reactive resistance at direct current. Therefore, if you remove the electrical unit from the bulgark, it will continue to work, especially if the mains voltage is low and the current used is constant.

AC Motors

The devices under consideration are AC and DC. In all areas where an electric motor is used, it often has an alternating current. This motor has a simple principle of operation and is easy to operate. The only significant disadvantage is the uncontrolled speed of rotation.

Electric AC motors can be with one or more phases. Devices where an AC electric motor is used are such machines that do not need to adjust the speed of rotation. They can have a different purpose (crushers, pumps, woodworking machines and so on). Their power ranges from two tenths to two hundred and more kilowatts.

Direct Current Motors

Electric DC motors can have along with a parallel and mixed connection of stator and armature windings. Their advantage is that it is inaccessible to the previous kind: it is the ability to regulate the speed of rotation. However, the use of force is necessary during operation.

Such motors are brushless and collector.

Brushless, or valve - are motors that operate in a closed system with a sensor that determines the rotary position and control system.

Collector motors can be self-excited (parallel, series and mixed) and independent excitation.

Devices that use DC motors are, for example, electric vehicles and various construction machines.

Asynchronous view

The most commonly used three-phase squirrel-cage induction motor. In this case, a circular magnetic field penetrates the short-circuited rotor winding, which causes an induction current. Asynchronous it is called because the rotation of the rotor is not equal to the rotation of the magnetic stator.

The use of electric motors of the asynchronous type is common in many branches of technology, in household appliances (refrigerators, washing machines, air conditioners), in industry, for example, in wood and metalworking, and also in weaving. They work more stable than other types, are cheaper and easier to operate.

Synchronous view

The synchronous motor has an excellent rotor structure, where this part is represented by an electric or permanent magnet. The rotational frequency in this case of the magnetic stator coincides with the rotor frequency.

This type of electric motors can be used in pumping stations, if necessary, reactive power compensation, as well as in some other cases.

Types of torque generation

By the way the torque appears, electric motors are divided into hysteresis and magnetoelectric.

The most common in traditional industries is the use of electric motors of the magnetoelectric type. They can be both on a constant, and on an alternating current. There are also universal engines.

But the industry where hysteresis electric motors are used, you can not call it widespread. Typically, such devices are unconventional and are rarely used in industry. More of them are used in gyroscopes, time counters, and also in devices for recording sounds and images.

Universal motors of collector type

Where are universal collector type electric motors used? Without them, industrial and household appliances, such as fans, juicers, meat grinders, vacuum cleaners, refrigerators, and the like, do not function. They operate both from a direct current network for one hundred and ten and two hundred and twenty volts, and from an alternating current network to 127 and 220 volts.

The arrangement of such motors is similar to the bipolar DC motors having a series excitation.

Here, not only an anchor is made from sheet-type electrical steel , but also a pole and yoke, that is, a fixed part of the magnetic wire.

The excitation winding can be connected from either one or the other side of the armature. Due to this, the radio interference caused by the motor is reduced. The same speed for both constant and alternating current is achieved by implementing an excitation winding with branches. The only difference is that with a DC network, it is used in its entirety, and only partially from an alternating current.

The rotational moment is obtained through the interaction of the current with the magnetic flux of excitation.

Such motors have a power of only five to six hundred watts (but in some cases, for example, in electric tools, reach eight hundred watts), as well as rotation speeds from two thousand seven hundred seventy to eight thousand revolutions per minute. Since the starting currents are small, then the starting resistors are not needed. The minimum number of pins on the universal manifolds is four. Of these, two are used to connect to a DC network, and two others are for AC. And in the latter case, the efficiency of the engine will be lower because of the large electrical and magnetic losses. The alternating current will be consumed more than constant, since it has not only the active component, but also the reactive one.

The speed can be adjusted, for example, by an automatic transformer or rheostat.

Quickly find a suitable mechanism

It is clear that there are a lot of areas where an electric motor is used.

195 3730.12.40 is an example number for identifying a particular mechanism, as well as its dimensions.

In view of the fact that the models of these devices are huge, and of various sizes and spheres of use, it is extremely difficult to find the necessary ones. This classification greatly simplifies the process of finding a suitable electric motor.