The principle of motor rotation, what is the principle of motor rotation

The rotation principle of the working principle of the three-phase asynchronous motor.

DC motor: first there is a magnetic field, and then the current is sent to the armature winding, the current-carrying conductor is stressed and moves, and the conductor current changes direction under different magnetic poles through the commutator to ensure that the direction of force is always consistent, so that the rotor rotates continuously in one direction.

AC asynchronous motor: the stator winding generates a rotating magnetic field, cutting the rotor winding to generate induced electric potential and induced current, and the current generates electromagnetic torque to drive the rotor to rotate.

AC synchronous motor: the stator winding generates a rotating magnetic field; The rotor windings are connected to direct current to generate a direct current magnetic field; Two magnetic fields attract each other, and the rotor is pulled and rotated by the rotating magnetic field.

1. The rotation principle of DC motor.

The DC motor is a magnetic field that does not move, and the conductor moves in the magnetic field; AC motors are rotating motion in a magnetic field, while the conductor is not moving. DC motors are divided into stator windings and rotor windings. The stator windings generate a magnetic field.

When direct current is on. The stator windings generate a magnetic field of fixed polarity. The rotor is powered by direct current in a magnetic field.

As a result, the rotor is rotated by force in the magnetic field.

Second, the rotation principle of single-phase AC motor.

Single-phase AC motors have only one winding, and the rotor is squirrel cage type. Single-phase electricity cannot produce a rotating magnetic field. To make the single-phase motor can rotate automatically, we can add a starting winding in the stator, the starting winding and the main winding are 90 degrees apart in space, and the starting winding should be connected in series with a suitable capacitor, so that the current with the main winding is approximately 90 degrees different in phase, that is, the so-called phase splitting principle.

In this way, two currents that differ by 90 degrees in time flow into two windings that differ by 90 degrees in space, and a rotating magnetic field (two-phase) is generated in space, under the action of which the rotor can start automatically.

The rotation principle of a three-phase asynchronous motor.

The prerequisite for a three-phase asynchronous motor to rotate is to have a rotating magnetic field, and the stator winding of the three-phase asynchronous motor is used to generate a rotating magnetic field. We know that the voltage between the phases of the three-phase power supply is 120 degrees different in phase, and the three windings in the stator of the three-phase asynchronous motor are also 120 degrees different from each other in the spatial orientation, so that when the three-phase power supply is passed into the stator winding, the stator winding will produce a rotating magnetic field, after the stator winding produces a rotating magnetic field, the rotor conductor (squirrel cage bar) will cut the magnetic field lines of the rotating magnetic field and produce an induced current, and the current in the rotor guide bar interacts with the rotating magnetic field to produce electromagnetic force, The electromagnetic torque generated by the electromagnetic force drives the rotor to rotate in the direction of the rotating magnetic field. In general, the actual speed of the motor is lower than the speed of the rotating magnetic field.

For this reason, we call the three-phase motor an asynchronous motor.

In general, the motor is to input a rotating magnetic field into the stator, and the rotor rotates in the rotating magnetic field to provide a rotating power source to the outside world, and there are many ways.

The principle of motor rotation is:

1. Permanent magnet.

A rotating electromagnet is placed in the middle.

The rotating shaft of the electromagnet is equipped with a commutator. The coil of the electromagnet can pass through the brushes.

and commutators energized.

2. When the coil is energized, the yellow side of the electromagnet becomes the S pole, and the green side becomes the N pole. At this point, the electromagnet and the permanent magnet attract each other, and the electromagnet starts rotating counterclockwise.

3. The electromagnet that starts to rotate cannot be stopped quickly, so it will lose over the horizontal position, turning the yellow side down, and the green side of the sock facing up.

4. At this time, the commutator is in contact with the previously opposite brush, so the direction of the current flowing through the electromagnet is also opposite. In this way, the yellow side will become the n pole, and the green side will become the S pole. At this point, the electromagnet and the permanent magnet attract each other and continue to rotate.

The reasons for the weakness of the electric motor are:

1. In three-phase voltage.

Motor insulated bearings and other transmission parts, power supply is out of phase or out of phase.

2. More than or lower than the rated working voltage of the motor.

3. Damage to mechanical parts (mainly bearings) and other components.

4. The rotor is broken, or the motor is lower than the original electrical standard after maintenance.

5. The motor works normally in the ultra-allowable temperature difference environment, and the three-phase asynchronous motor is used.

The reason why the torque becomes smaller and the speed slows down is that there are short circuits between the turns of the three-phase winding of the motor (it seems that the joints should be disassembled to distinguish the impedance of the windings separately) or the wire gauge and the number of turns are wrong when embedded winding.

There are many forms of motors, but their working principles are all based on the laws of electromagnetic induction and electromagnetic forces. Therefore, the general principle of its construction is to use appropriate magnetic and conductive materials to form magnetic circuits and circuits that carry out electromagnetic induction with each other, so as to generate electromagnetic power and achieve the purpose of energy conversion.

According to the different starting and operation modes of the motor, it can be divided into capacitive starting single-phase asynchronous motor, capacitive running single-phase asynchronous motor, capacitor starting single-phase asynchronous motor and split-phase single-phase asynchronous motor, three-phase motor.

According to the structure of the motor, it can be divided into cage induction motor, which is the one you are using (the old standard is called squirrel cage asynchronous motor) and the wound rotor induction motor (the old standard is called the wound asynchronous motor). A squirrel cage is a closed coil.

1) When the three-phase asynchronous motor is connected to the three-phase AC power supply (each with a difference of 120 degrees of electric angle), the three-phase stator winding flows through the three-phase symmetrical current to generate the three-phase magnetodynamic potential (stator rotation magnetodynamic potential) and generate a rotating magnetic field, which rotates clockwise along the inner circular space of the stator and rotor at a synchronous speed.

2) The rotating magnetic field and the rotor conductor have a relative cutting and hail movement, according to the principle of electromagnetic induction, the rotor conductor (the rotor winding is a closed path) generates an induced electromotive force and generates an induced current (the direction of the induced electromotive force is determined by the right-hand rule).

3) According to the law of electromagnetic force, under the action of induced electromotive force, an induced current will be generated in the rotor conductor that is basically consistent with the direction of the induced electromotive force. The current-carrying convolutor conductor is subjected to electromagnetic force in the magnetic field generated by the stator (the direction of the force is determined by the left-hand rule), and the electromagnetic force forms an electromagnetic torque on the motor rotor shaft, which drives the motor rotor to rotate along the direction of the rotating magnetic field, and when the motor shaft is loaded with mechanical load, it outputs mechanical energy outward. Since the magnetic flux of the part without a short-circuit ring is superior to that of the part with a short-circuit ring, the direction of rotation of the motor is the same as that of the rotating magnetic field.

Please help me if mine is helpful to you!

What is the principle of motor rotation? Hello dear, 1. The rotation principle of DC motor: it follows the principle of "energized wire should be subjected to force in the magnetic field, and the direction is determined by the left-handed rule."

Depending on how the magnetic field is generated, micro motors and smaller DC motors use permanent magnets as the poles. Larger DC motors use energized coils to generate a magnetic field, which is stronger and larger. 2. Rotation principle of three-phase three-phase sinusoidal AC motor:

Sinusoidal alternating current has a phase difference of 120 degrees, and a rotating magnetic field can be generated on the stator of the motor, and the starting torque is very large, and the output power and efficiency are also very high. When the rotor bucket quietly uses short-circuit copper strips, it is called a squirrel cage asynchronous motor, which is relatively simple to manufacture and use. When the rotor adopts the winding method, it is called a winding synchronous motor, which is easy to adjust the speed of the wide motor and start with load.

3. Rotation principle of single-phase sinusoidal AC motor: single-phase sinusoidal alternating current is a 180-degree polarity change on the magnetic pole, and there is no starting torque, but as long as there is a small deflection, it will start. There are short-circuit loop start mode and capacitor start method.

An electric motor is a device that converts electrical energy into mechanical energy.

Its principle is to use an energized coil (that is, stator winding) to generate a rotating magnetic field, and act on the rotor squirrel cage closed aluminum frame to form magnetoelectric dynamic rotational torque.

The motor is divided into DC motor and AC motor according to the different power sources, and most of the motors in the power system are AC motors, which can be synchronous motors or asynchronous motors (the magnetic field speed of the stator of the motor is not synchronized with the rotation speed of the rotor).

The motor is mainly composed of a stator and a rotor, and the direction of the energized wire in the magnetic field is related to the direction of the current and the direction of the magnetic inductance line (magnetic field direction). The working principle of the motor is the effect of the magnetic field on the current force, which makes the motor rotate.

The electric motor uses the principle of the force of an energized conductor in a magnetic field (this is different from the magnetic effect of electric current, and the current version of eighth-grade physics clearly separates the two), and the rubber belt base of this principle is the Danish physicist Oster.

He was born on 14 August 1777 in Ruudchobin on the island of Langerang to a family of pharmacists. He was admitted to the University of Copenhagen in 1794 and received his doctorate in 1799. 1801 In 1803, he visited Germany, France and other countries, and became acquainted with many physicists and chemists.

Professor of Physics at the University of Copenhagen from 1806 and Permanent Secretary of the Royal Danish Society from 1815. In 1820, he was awarded the Copley Medal of the Royal Society for his outstanding discovery of the magnetic effect of electric currents.

In 1829 he was appointed director of the Copenhagen Institute of Technology. He died in Copenhagen on March 9, 1851. He has conducted extensive research in physics, chemistry, and philosophy.

Influenced by Kant's philosophy and Schelling's natural philosophy, he firmly believed that natural forces could be transformed into each other, and explored the connection between electricity and magnetism for a long time. In April 1820, he discovered the effect of electric current on magnetic needles, that is, the magnetic effect of electric current.

On July 21 of the same year, he published his findings under the title "Experiments on the Collision Effect of Magnetic Needles". This short ** caused a great shock in the European physics community, led to the emergence of a large number of experimental results, and thus opened up a new field of physics electromagnetism.

Categories: Education, Science, >> Science & Technology.

Problem description: I know that the direction of rotation of the motor is related to the direction of the current, but what does it have to do with it?

What is the left-handed law?

If a wire is connected to the left and right ends of the power supply, then it is one"Electromagnets", there is a magnetic field, so what is the direction of the magnetic field for this wire?

I'm a junior high school student, and my teacher won't tell me, he said it's high school content, and I've taught myself the compulsory 1 and 2 in high school

Analysis: The law of the left and right hands has been said very clearly, let me add to the question of how the motor rotates. If you are a junior high school student, it may be difficult for you to understand this.

First of all, the power supply for the motor is the dust bureau of three-phase alternating current (ABC three-phase), and the electric principle of non-junior high school is single-phase, and the three-phase coil (abcabcabc...) is placed in the stator of the motor in turnIn this way, a garden circumference is formed, and when the power is applied, an alternating magnetic field of 3,000 revolutions per minute is formed inside the motor. The rotor of the motor (the rotating part of the motor) becomes a magnet with ns poles after being energized, so that the alternating magnetic field of the stator and the magnetic field of the rotor interact with each other, and the rotor is driven to rotate along the direction of the alternating magnetic field, lagging behind the speed of the alternating magnetic field.

That is to say, the speed of rotor rotation is always less than the speed of the alternating magnetic field, the speed of the alternating magnetic field is constant, and the speed of the rotor rotation is about 3000 divided by the number of rotor pole pairs, and the rotor has a pair of ns poles is a pair of poles, and two pairs of ns poles are two pairs of poles, so that the speed of the motor can be changed by changing the number of pole pairs of the rotor.

I don't know if you understand this, I wish you a speedy success.

1. The rotating magnetic field drives the rotor to rotate. The motor is composed of a stator and a rotor, one generates a rotating magnetic field, and the other is a magnetic pole.

2. The rotation principle of the DC motor: the DC motor is a magnetic finger field that does not move, and the conductor moves in the magnetic field; The AC motor is a magnetic field rotating motion, while the conductor does not move, the DC motor is divided into stator winding and rotor winding, and the stator winding generates a magnetic field. When direct current is applied, the stator generates a magnetic field of fixed polarity around the Qin Tuntan group, and the rotor is stressed in the magnetic field by direct current, so the rotor rotates under force in the magnetic field.

3. It is named because it rotates continuously along the cylindrical surface of the stator and rotor core. The rotating magnetic field is the basic condition for the conversion between electrical energy and rotational mechanical energy.

4. Usually the stator of the three-phase AC motor has a symmetrical three-phase winding (see armature winding). When an alternating current is applied to the windings of any phase, a pulsating magnetic field is generated. However, if a balanced three-phase current is fed into the three symmetrical windings, a magnetic field rotating in space is generated.

The working principle of electric motors is based on the law of electromagnetic induction, the Lorentz force, and Faraday's law of electromagnetic induction.

The motor is mainly composed of two parts: the stator and the rotor. The stator is immobile and consists of an electromagnet coil, an iron core and an end cap, etc.; The rotor can be rotated and consists of a shaft, a core, and a coil. In an electric motor, there is a rotating magnetic field between the stator and the rotor, and this magnetic field is provided by the AC power source.

When an electric current passes through the coil in the stator, a rotating magnetic field is generated in the stator, and this magnetic field acts on the coil on the rotor, causing the coil on the rotor to feel a rotational moment and start rotating. Since the coil on the rotor is fixed to the rotor, it will also rotate with the rotor.

When the motor is running, the coil in the stator constantly changes the direction and magnitude of the current of the consultane, and thus the direction and magnitude of the rotating magnetic field. In this way, the rotor is subjected to a constantly changing rotational moment and thus remains rotating all the time.

In short, the working principle of the electric motor is to use the current in the stator to generate a rotating magnetic field, which acts on the coil on the rotor, causing the rotor to receive a rotational moment and thus start rotating. The speed and torque of the motor can be controlled by changing the magnitude and direction of the current.

Precautions for using electric motors

1. Use power supply: The motor needs to be connected to the power supply to operate normally. When using the power supply, it is necessary to ensure that the voltage and frequency of the power supply are consistent with the rated voltage and frequency of the motor, so as to avoid damage to the motor due to voltage or frequency mismatch.

2. Installation and fixation: The motor needs to be fixed on the mount to ensure the stability and safety of the motor. When installing, it is necessary to follow the installation instructions of the motor and choose the installation location and method correctly.

3. Maintenance: The motor needs to be maintained regularly, including cleaning, lubrication, fastening, checking electrical components, etc., to ensure the normal operation of the motor and prolong the service life.

4. Monitor the operating status: When the motor is running, it is necessary to monitor the operating status of the motor, including current, voltage, temperature and other parameters, as well as noise and vibration indicators, and find and deal with abnormal situations in time.

5. Safe operation: When using the motor, it is necessary to pay attention to safe operation, abide by the instructions for the use of the motor, prohibit overload operation, prohibit forcibly opening or closing the motor, etc., to ensure personal safety and equipment safety.