Working principle, functional characteristics and wiring method of asynchronous motor

Asynchronous motor, also known as AC induction motor, is a type of electric motor and one of the most common types of motors. It works by applying an AC voltage to the stator windings. Unlike traditional DC motors, it does not require a DC power supply. When the motor is powered on, an alternating magnetic field is formed in the stator windings. This magnetic field induces current on the rotor, causing the rotor to rotate. Due to its complex working principle, asynchronous motors have the advantages of high efficiency, simple structure, easy use and maintenance, and low cost. They are widely used in industrial production, transportation, household appliances and other fields.

Working principle of asynchronous motor

Asynchronous motor is a common electric motor, mainly used in industrial and household appliances. Its working principle is based on Faraday's law of electromagnetic induction and Lorentz force. The following is the working principle of asynchronous motor:

1. An electric motor consists of a stationary external magnetic field (called the stator) and a rotating internal magnetic field (called the rotor).

2. When the three-phase alternating current (or single-phase current) in the stator passes through the coil, a rotating magnetic field is generated in the stator.

3. Since the conductor in the rotor is in the stator's magnetic field, it experiences a rotational force (called the Lorentz force), causing the rotor to begin to rotate.

4. The rotor rotates at a slightly slower speed than the rotating magnetic field, so the induced current in the rotor generates a magnetic field that opposes the magnetic field of the stator, causing the rotation speed to slow down.

5. Due to this effect, the asynchronous motor can automatically keep synchronization with the AC power system in the stator by adjusting the rotation speed of the rotor, thereby achieving stable torque output.

6. The rotor of an asynchronous motor is usually made of materials such as aluminum or copper bars, which enable it to conduct electric current and generate a rotating magnetic field. At the same time, the coils in the stator can be made of highly conductive materials such as copper or aluminum wire to improve efficiency and reliability.

In short, the working principle of the asynchronous motor is to use the interaction between electromagnetic induction and Lorentz force to generate a rotating magnetic field, thereby achieving rotational power output.

Functional characteristics of asynchronous motor

Asynchronous motor, also known as AC asynchronous motor, is a commonly used type of motor. Its functional characteristics are as follows:

1. High efficiency: Asynchronous motors have high efficiency and can convert electrical energy into mechanical energy with less power loss.

2. High reliability: Asynchronous motors have long life, simple structure, and are not easily affected by load changes.

3. Strong adaptability: Asynchronous motors can adapt to various loads and working conditions and are a universal motor.

4. Strong starting ability: The asynchronous motor has strong starting ability and can adapt to various loads and starting conditions.

5. Low maintenance cost: The maintenance cost of asynchronous motor is low because of its simple structure and easy maintenance.

6. Low noise: Asynchronous motors have low noise and are suitable for places that require a low noise environment.

7. High flexibility: Asynchronous motors can achieve variable speed operation by controlling the frequency and voltage of the power supply, which is flexible.

In short, asynchronous motors have a series of advantages such as high efficiency, high reliability, strong adaptability, strong starting ability, low maintenance cost, low noise and high flexibility, so they are widely used.

Wiring method of asynchronous motor

The wiring methods of asynchronous motors are mainly divided into two types: star connection and delta connection. The following is a detailed explanation of the two wiring methods:

1. Star connection:

In the star connection, the terminals of the three-phase coils are connected to a common neutral point. This neutral point is usually called the "star point". At the same time, the star point is also the connection point for the power supply connection. The star connection method provides a higher starting torque for the motor than the delta connection.

2. Triangle connection:

In the delta connection, the terminals of the three-phase coils are connected to form a closed triangle. The power supply wires are directly connected to the three terminals of the motor.

Since the resistance value of the delta connection is relatively high, a larger starting current is required to start the motor, so the starting torque of the delta connection is smaller than that of the star connection.

It should be noted that due to the different structures and working methods of motors, the specific wiring method and number of wiring pins of the motor may be different. It is recommended to check the wiring diagram and technical manual of the motor before wiring to ensure the correct wiring method.