Introduction to synchronous motors, what kind of motors are synchronous motors

If the servo motor is an AC motor, it is frequency conversion speed regulation; If the servo motor is a DC motor, it is DC voltage and speed regulation; All servos can be regarded as "PLC + motor speed regulation circuit + encoder".The start, acceleration, constant speed, deceleration and stop commands on the servo speed ladder diagram are all completed and output by the PLC counter; These running instructions arrive at the speed regulating circuit, and the speed regulating circuit implements the starting, acceleration, constant speed, deceleration and parking of the servo motor; The position ring is a counter of the PLC, the number of command pulses given by the user is used as the subtracted number, the pulse fed back by the encoder is used as the subtracted counting pulse, and the output number of the counter is compared with the given comparison circuit to output various running instructions.

Synchronous motors, like induction motors, are commonly used AC motors1. Synchronous motor is the heart of the power system, it is a set of rotation and stationary, electromagnetic change and mechanical movement in one, to achieve the conversion of electrical energy and mechanical energy components, its dynamic performance is very complex, and its dynamic performance has a great impact on the dynamic performance of the whole power system. Features are:

In steady-state operation, there is a constant relationship between the speed of the rotor and the frequency of the gridn=ns=60f p, where f is the frequency of the grid, p is the number of pole pairs of the motor, and ns is called the synchronous speed. If the frequency of the grid is constant, the speed of the synchronous motor is constant at steady state, regardless of the size of the load. Synchronous motors are divided into synchronous generators and synchronous motors.

AC engines in modern power plants are dominated by synchronous generators.

Hello landlord: A synchronous motor is also an AC motor. It is mainly used for generators, but also for motors, and is generally used for production machinery with large power and speed that does not require adjustment, such as large water pumps, air compressors and mine ventilators.

In recent years, due to the development of permanent magnet materials and electronic technology, micro synchronous motors have been more and more widely used.

One of the characteristics of synchronous motors is that there is a strictly constant relationship between the speed n during stable operation and the frequency f1 of the stator current, ie.

n=60f1/p=n0

The rotational speed n of the synchronous motor is the same as the rotational speed n0 of the rotating magnetic field. Hence the name "synchronicity".

Needless to say, the stator of the synchronous motor also needs to be energized to keep it synchronized with the stator. (The rotor of the micro synchronous motor can be made of permanent magnet magnets).

Asynchronous motors are different, the stator windings are energized to produce a rotating magnetic field, which induces a current in the rotor to rotate the motor. The structure is simpler than that of synchronous motors.

What is an asynchronous motor?

The asynchronous motor is an AC motor based on the interaction between the air-gap rotating magnetic field and the induced current in the rotor winding to generate electromagnetic torque, so as to realize energy conversion. Since the rotor winding current is induced, there is a certain difference between its rotational speed and synchronous rotational speed.

Difference Between Asynchronous Motor and Synchronous Motor:

The number of revolutions is fixed during normal operation of the synchronous motor and does not change due to the change of load.

The number of revolutions is not fixed during normal operation of the asynchronous motor, but will change slightly due to the change of load. Synchronous motors have complex circuits and reversible energy (motors and generators are theoretically interchangeable) and are mostly used as generators.

Synchronous motors are the counterpart of asynchronous motors, but their principles are completely different. The main reason why an asynchronous motor is called asynchronous is that the speed of its rotor is lower than the speed of the rotating magnetic field generated by its stator. So from this direction, the rotation speed of the rotor of the synchronous motor is the same as the rotation speed of the magnetic field, so it is called synchronization.

The operating principle of the synchronous motor:

1.The stator windings of synchronous motors and asynchronous motors are exactly the same, without any difference. Of course, there are differences in size, etc., but they all work the same.

2.When the synchronous motor is running, a rotating magnetic field is immediately generated when the stator windings are fed into the power supply.

3.The rotor of the synchronous motor has an excitation winding, and a static magnetic field will be generated when direct current is applied to the excitation winding.

4.The magnetic poles of the rotor and stator of the synchronous motor are exactly the same.

5.Then the magic happens, the rotor magnetic field will be affected by the magnetic pull of the stator magnetic field. However, it should be noted that when started in this way, the synchronous motor will be completely motionless.

Dear What is a synchronous motor? : Synchronous motor is a kind of AC motor, its speed is related to the frequency of the power supply and the number of poles, so it is called synchronous electric ear drain motor.

The coil on the stator is powered by an AC power source, and the rotor rotates by a magnetic field, so it is a brushless motor. Synchronous motors have the advantages of high efficiency, stability and reliability, and are widely used in industrial, transportation and civil fields.

Summary. Hello, synchronous motor is an AC motor that rotates at synchronous speed by interacting with the DC powered excitation magnetic field and the rotating magnetic field of the armature to produce torque.

Hello, the synchronous motor is an AC motor that rotates at synchronous speed by interacting with the magnetic field of the excitation large hole of DC power supply and the rotating magnetic field of the armature to produce torque. Rolling state withered.

Zhongsheng Shen defeated the text name synchronous motor foreign name synchronous motor characteristics of the synchronous motor structure for the operation of the electric filial piety cover motive classification with direct current excitation, motor starting without excitation can only be noisy under the synchronous speed to produce average torque, belonging to the classification of AC motor.

Synchronous motor can be adjusted to make it run under the advanced power factor, which is conducive to improving the power factor of the power grid. This is especially advantageous when synchronous motors are used in large equipment at low speeds. In addition, the rotational speed of the synchronous motor is completely dependent on the frequency of the mains supply.

When the frequency is constant, the speed of the motor is also constant, and it does not change with the load.

Why is the air gap in the synchronous motor so small?

In order to reduce the excitation current and improve the power factor, the air gap should be reduced as much as possible.