The principle of a three phase motor? What is the principle of three phase AC motor?

Three-phase electricity. The motor should be divided into synchronous motor and asynchronous electric, the meaning of three-phase is that the voltage, frequency and other phase difference of 120 degrees electrical angle is indeed three-phase power supply, when the motor is connected to the three-phase electricity can produce a rotating magnetic field; Asynchronous refers to the speed at which the rotational speed of the rotor lags behind the rotating magnetic field; An electric motor converts electrical energy into mechanical energy.

A device. Three-phase asynchronous motor.

Working principle: When the motor is connected to three-phase electricity, an alternating magnetic field is generated, and the rotor winding cuts the magnetic field lines in the magnetic field to produce a current Because the rotor winding itself forms a closed loop, the current in the rotor winding and the electricity in the stator winding interact to produce a moment, so the motor rotates. The rotor winding of the synchronous motor is a slip ring at the end of the coil to access three-phase electricity.

The structure of the asynchronous motor is simple to use and maintain, so it is widely used but the efficiency is not as high as the synchronous motor, the rated current of the motor includes: active current and reactive current, part of the reactive current is used to generate a magnetic field is also necessary, the other part is the loss of magnetic force in silicon steel and the loss of overcoming mechanical resistance, high permeability materials should be selected when manufacturing the motor, and the motor should rotate flexibly during maintenance to reduce the reactive current and improve the power factor.

Three-phase asynchronous motor.

By machine base, iron core, stator coil, rotor, end cap.

and so on. How it works; Upper class in the stator.

Overcurrent. , an induced electric potential is generated on the rotor, and the magnetic field generated by this induced electric potential and the stator loop are the generated magnetic fields that interact to produce a rotational torque that makes the rotor rotate because.

Three-phase power supply. It is the change of size and direction of the surface with time, so in.

Stator windings. When the distribution of the three phases is 120 degrees apart in space, the three-phase power supply produces a rotating magnetic field, and from the previous analysis, the rotor also obtains a continuous rotating torque, and the motor rotates.

If you are interested, you can find a professional textbook to take a look at, the difficulty is different, choose your own suitable one, it is easy to understand.

The working principle of the three-phase motor is: when the three-phase stator winding of the motor (each differs by 120 degrees of electric angle), after the three-phase alternating current is introduced, a rotating magnetic field will be generated, which cuts the rotor winding, thereby generating induced current in the rotor winding** The sub-winding is a closed path), the current-carrying rotor conductor will generate electromagnetic force under the action of the stator rotating magnetic field, so as to form an electromagnetic torque on the motor shaft, drive the motor shaft to rotate, and the motor rotation direction is the same as the direction of the rotating magnetic field.

The working principle of a three-phase motor is based on the interaction of the stator rotating magnetic field and the rotor current.

Under the action of the rotating magnetic field of the stator, the rotor conductor cuts the magnetic field lines (in the opposite direction of rotation of the rotating magnetic field), thus generating an induced electromotive force in the conductor and thus an induced current. According to Ampere's law of electromagnetic force, the rotor current interacts with the rotating magnetic field to produce an electromagnetic force, which forms an electromagnetic torque on the axis of the rotor, and the direction of the torque is the same as that of the rotating magnetic field, and the rotor is affected by this torque and rotates according to the rotation direction of the rotating magnetic field.

The stator of the motor has three symmetrical windings, which are connected to the three symmetrical power supply, flow through the three symmetrical currents, generate a rotating magnetic field (electromagnetism), cut the rotor conductor, induce electric potential and current (magnetic transformation), and the current-carrying conductor is affected by electromagnetic force in the magnetic field to form electromagnetic torque (electromagnetic generating force), so that the rotor rotates in the direction of rotation of the rotating magnetic field.

In general, the rotational speed of the rotor.

Always slightly below the sync speed.

Hence the name "asynchronous", deterioration.

It is a necessary condition for the operation of the asynchronous motor, and the percentage value of the ratio of the slip to the synchronous speed is called the slip rate s:

The magnetic field here refers to the stator winding after the energization, because the stator winding is a three-phase alternating current, there is a fixed electrical angle between the three phases of the three-phase alternating current, that is to say, the difference between the three phases is 120 degrees, if one of the phases does not move, the other two phases are ahead and lagging behind this phase respectively. That is to say, the instantaneous value of the three-phase electricity at the same moment is not equal, so the magnetic field generated by the three-phase winding in the stator cavity is not fixed, but is generated at one time according to a certain frequency and "sequence", and this process will be a "rotation" process when connected in a period of time, so the rotor will rotate. The speed of the rotor rotation is the speed of the motor, and the speed has been determined after the design and production of the motor, because the speed depends on the number of pole pairs of the motor, the larger the number of pole pairs, the lower the speed, and vice versa.

1. Three-phase alternating current.

Machine principle: When the three-phase stator winding of the motor (each with a difference of 120 degrees of electric angle), after the three-phase alternating current is introduced, a rotating magnetic field will be generated, which will cut the rotor winding, thereby generating an induced current in the rotor winding.

The rotor windings are closed paths).

2. The motor is also known as (commonly known as the motor), which is represented by the letter "M" (the old standard is represented by "D") in the circuit. Its main function is to generate driving torque, as a power source for electrical appliances or various machinery, the motor system is fully enclosed, external fan cold, squirrel cage structure.

Before answering your question, you need to understand a question, what is three-phase alternating current, three-phase alternating current is a form of electrical energy, referred to as three-phase electricity. Three-phase AC power supply is a power supply composed of three alternating currents with the same frequency, equal amplitude, and 120° difference in phase. The simple understanding is that the motor is composed of three-phase windings, and when the three-phase electricity is sent into the winding, due to the phase and instantaneous value of the three-phase electricity, a rotating magnetic field will be generated in the winding, which will then drive the rotor to rotate.

Are you talking about asynchronous motors? The asynchronous motor uses the lag between the rotor and the stator electric field represented by the slip rate S to form a traction.

What is the origin of three-phase alternating current? How an induction motor works.

The electric motor is made by using the phenomenon of the energized coil rotating under force in the magnetic field, and the principle of the energized conductor being forced in the magnetic field is utilized.

The direction of force on an energized conductor in a magnetic field is related to the direction of the current and the direction of the magnetic pole.

In the model of the DC motor, the energized coil is the rotor, and when the coil continuously changes to the direction, the coil continuously rotates at a constant speed under the action of this force.

In the home circuit, people often use two inlet wires, one called the zero line and the other called the live wire, to meet the needs of electrical appliances.

Summary. Motors are divided according to the type of working power supply: DC motor and AC motor.

DC motors can be divided into brushless DC motors and brushed DC motors according to their structure and working principle. Brushed DC motors can be divided into:

Permanent magnet DC motor and electromagnetic DC motor. Electromagnetic DC motors are divided into: series excited DC motors, parallel excited DC motors, separately excited DC motors and compound excited DC motors.

The working principle of a three-phase AC motor.

Dear, hello, I'm glad to have your question, the working principle of the three-phase AC motor, help you inquire: electromagnetic induction as the principle of action.

Three-phase AC motor principle: When the three-phase stator windings of the motor (each with a difference of 120 degrees of electrical angle), after the three-phase alternating current is introduced, a rotating magnetic field will be generated, and the rotating magnetic field will cut the rotor winding, thereby generating an induced current in the rotor winding The rotor winding is a closed path.

Because the operation of the three-phase asynchronous motor is based on the principle of electromagnetic induction, it is also called "induction motor". Since the phase difference of the three-phase AC power supply is 120, the windings of the three-phase AC asynchronous motor should also be consistent with the AC power supply.

Motors are divided according to the type of working power supply: DC motor and AC motor. DC motors can be divided into according to structure and working principle:

Brushless DC motors and brushed DC motors. Brushed DC motors can be divided into: permanent magnet DC motors and electromagnetic DC motors.

Electromagnetic DC motors are divided into: series excited DC motors, parallel excited DC motors, separately excited DC motors and compound excited DC motors.

The synchronous motor not only has a high power factor, but also its speed is independent of the load size, and is only determined by the grid frequency. The operation is relatively stable. DC motors are often used in occasions that require wide planning speed regulation.

But it has commutators, messy structure, **expensive, difficult to protect, and not suitable for harsh environments.

In the production, the main use is AC motors, especially three-phase asynchronous motors, because it has the advantages of simple structure, sturdy and durable, reliable operation, low cost and easy maintenance. It is widely used to drive various metal cutting machine tools, cranes, forging presses, conveyor belts, foundry machinery, low-power ventilators and water pumps.

Hello dear, according to the situation you described, the working principle of the three-phase AC motor, the working principle of the three-phase asynchronous motor is based on the interaction of the rotating magnetic field of the stator (the resultant magnetic field generated by the three-phase current in the stator winding) and the rotor current ** the current in the sub-winding). When the symmetrical three-phase winding of the stator is connected to the three-phase power supply, a symmetrical three-phase current will be passed into the winding, and a rotating magnetic field will be generated in space, and the magnetic field will rotate along the circumferential direction of the stator, when the magnetic field rotates, the conductor cutting magnetic flux of the rotor winding will produce an induced electromotive force e, and due to the presence of electromotive force e, a rotor current i will be generated in the rotor winding. According to Ampere's law of electromagnetic force, the interaction of the rotor current with the rotating magnetic field will produce an electromagnetic force f (the direction of which is determined by the left-hand rule), which forms an electromagnetic torque on the axis of the rotor, and the direction of the torque is the same as that of the rotating magnetic field, and the rotor is subjected to this torque and rotates in the direction of rotation of the rotating magnetic field.

However, the rotational speed n of the rotor is constant less than the rotational velocity n of the rotating magnetic field (called synchronous rotational speed), because if the two rotational speeds are equal, the rotor and the rotating magnetic field have no relative motion, and the rotor conductor does not cut the magnetic flux, it cannot generate induced electromotive force and current, and there is no electromagnetic torque, and the rotor will not continue to rotate. Therefore, the speed difference between the rotor and the rotating magnetic field is the main factor that guarantees the rotation of the rotor.

The corresponding rated voltage is: 380 220V; 220 also refers to the three-phase power supply.

Three-phase asynchronous motor (triple-phase asynchronous motor) is a kind of inductive car motor, is a kind of motor that is powered by simultaneous access to 380V three-phase AC current (phase difference 120 degrees), because the rotor and stator of the three-phase asynchronous motor rotate in the same direction and at different speeds, there is a slip rate, so it is called a three-phase asynchronous motor.

The rotation speed of the rotor of the three-phase asynchronous motor is lower than the rotation speed of the rotating magnetic field, and the rotor winding generates electromotive force and current due to the relative motion between it and the magnetic field, and interacts with the magnetic field to generate electromagnetic torque to achieve energy conversion. Compared with single-phase asynchronous motors, three-phase asynchronous motors have good running performance and can save various materials.

According to the different rotor structures, three-phase asynchronous motors can be divided into cage type and winding type. The asynchronous motor of the cage rotor has a simple structure, reliable operation, light weight and low cost, and has been widely used, but its main disadvantage is that it is difficult to regulate the speed.

The rotor of the wound three-phase asynchronous motor, like the stator, is also provided with a three-phase winding and is connected to an external varistor through slip rings and brushes. Adjusting the rheostat resistance can improve the starting performance of the motor and adjust the rotational speed of the motor.

Three-phase asynchronous motor principle: when the three-phase stator winding of the motor.

After three symmetrical alternating currents are introduced, a rotating magnetic field will be generated, which cuts the rotor windings, thereby generating an induced current in the rotor windings**The sub-winding is a closed path), and the current-carrying rotor conductor will generate electromagnetic force under the action of the stator rotating magnetic field, thus forming an electromagnetic torque on the motor shaft, driving the motor to rotate, and the motor rotation direction is the same as the direction of the rotating magnetic field.

When a conductor cuts magnetic field lines within a magnetic field, an induced current is generated within the conductor, hence the name "induction motor". The combined action of the induced current and the magnetic field exerts a driving force on the motor rotor.

We let the closed coil ABCD rotate around the axis XY within the magnetic field B. If the magnetic field is rotated in a clockwise direction, the closed coil is subjected to a variable magnetic flux, which generates an induced electromotive force that generates an induced current (Faraday's law). According to Lenz's law, the direction of the current is:

The effect of the induced current is always to hinder the cause of the induced current. Thus, each conductor such as a wheel is subjected to a Lorentz force in the opposite direction of motion with respect to the induced magnetic field.

A simple way to determine the direction of the f-direction of each conductive force is to use the right hand to specify the direction of the force with the right hand (the magnetic field acts on the current, place the thumb on the square of the induced magnetic field, and the index finger is the direction of the force. Place the middle finger in the direction of the induced current. In this way, the closed coil is subjected to a certain torque and thus rotates in the same direction as the induced submagnetic field, which is called the rotating magnetic field.

The electric torque generated by the rotation of the closed coil balances the load torque.