Types of electric motors and their features

Types of electric motors and their features

The invention of electric motors was the impetus for the development of industry and improving the quality of life. They are used in many industries, in transport, in everyday life. There are many types of electric motors, but the principle of their operation and device remain unchanged. The unit consists of:

1.      Moving parts (rotor or anchor)

2.      Fixed part (inductor or stator)

The mechanism is based on the principle of electromagnetic induction. The magnetic field generated during the rotation of the rotor leads to the repulsion of its poles from the stator. The engine converts electrical energy into mechanical energy. It has a large resource and is compact and produces little noise.

Electric motors

Consider the types of electric motors and their features.

DC motors, which include:

Inductor consisting of a bed and main / auxiliary poles. It creates a motionless magnetic field.

An anchor, which is a magnetic system of a working winding, sheets of iron and a collector.

Brushes for collecting current from the collector.

Brush holders that hold the brushes in position.

DC motors are divided into:

Collector, where the current is switched in the windings using a brush-collector assembly, which also serves as a sensor for the position of the rotor. They are affordable, but have some disadvantages. The contact of the brushes with the collector leads to their wear and sometimes to overheating of the unit. Switching the armature windings and sparking brushes causes interference.

Brushless, based on self-synchronizing frequency regulation. They are characterized by efficiency and higher efficiency, which is achieved due to the absence of switching contacts and torque.

DC MOTORS are equipped with vehicles, hoists, drilling rigs, excavators, etc.

AC motors are a simpler, cheaper and more reliable design. 

They are of two types:

Synchronic Motors: in which the rotor speed and the rotation frequency of the magnetic field are the same. Their subspecies include stepper motors, where a single current pulse rotates the rotor by a certain angle. It is possible to control revolutions and torque within wide limits, as well as reversing by changing the sequence of signals.

Asynchronous Motors: with different rotational speeds of the magnetic field and rotor. In such units, rotors of two types can be used - phase and squirrel-cage.

Induction motors, in turn, are divided into:

Single Phase: with one working winding on the stator. Their launch is carried out either by switching on a separate starting winding, or by a starting push. They are intended for use in low-power devices (domestic fans, small pumps, etc.).

Two-phase, with two windings perpendicular to the stator (one of them is directly connected to the alternating current network, the second - with the help of a phase-shifting capacitor), which create a rotating magnetic field. Engines of this type are capable of self-starting. They can be found in washing machines and machines for various purposes.

Three-phase: with three working windings, arranged in such a way that the rotating magnetic fields formed by them are offset by 120 degrees relative to each other. The windings are connected either according to the "triangle" scheme, or according to the "star" scheme. The second option requires a higher voltage. The three-phase type of motor is considered the most perfect, since there are no problems with reverse. Such engines are installed on winches, industrial machines, cranes, circular saws, etc.

Advantages of electric motors

Now that we have found out what types of electric motors are, let's talk about their advantages, among which we can list:

Simplicity of design: The minimum number of nodes reduces the possibility of breakage.

Reliability and ease of management: Engines of any type are easy to start and last long enough.

Compact and versatile: They are suitable for installation in trams, on small machines, in household appliances, etc.

Environmental friendliness: When the engines are running, no harmful chemicals, steam or decay products are released.

High efficiency:

The possibility of reverse, achieved by changing the poles of the armature (in the collector electric motor) or the order of the inclusion of phases (in three-phase).

Low noise due to lack of vibration

Possibility of operation under any conditions

Electric motors entered our life more than a century ago and are now widely used in almost all areas of the national economy, making our life more comfortable.