Tag: synchronous motor

Most people understand that synchronous motors use power to generate motion. Some motors are powered by DC current, others by AC current, others by a combination of the two, and their specific method of energy transfer is unique to each motor. This article will focus on synchronous motor. It aims to explain the definition, features of synchronous motors and differences between induction motor, so that anyone looking to use one of these devices has the relevant information to do so.

A synchronous motor is an AC motor in which the rotation of the rotor is synchronized with the frequency of the supply current. That is, the period of rotation of the rotor is equal to the rotating magnetic field of the machine in which it is placed. In this article, we will introduce synchronous motor working principle. The working principle of synchronous motor is magnetic lock. When two different magnetic poles meet, a huge pull-off force is created between the two magnetic poles.

With the development of new materials, mechatronics, power electronics, computers and other related new technologies, synchronous motor control system has opened up a wide range of applications, to achieve high speed, high precision, high stability, fast response, high efficiency and energy saving motion control. In industrial and agricultural production, there are a large number of production machines that require continuous single-direction operation at roughly constant speed.

Synchronous motors, like induction motors (asynchronous motors) are a common type of AC motors. Synchronous motor is the heart of power system, it is a set of rotation and static, electromagnetic change and mechanical movement in one, to achieve electrical and mechanical energy conversion components. Synchronous motors can be divided into reluctance synchronous motor, hysteresis synchronous motor and permanent magnet synchronous motor. In this article, we will introduce these three types synchronous motor.

A synchronous motor is an AC motor that rotates at a synchronous speed by interacting with the excitation magnetic field of the DC power supply and the rotating magnetic field of the armature to generate torque.

Synchronous motor is a common AC motor, it is the heart of the power system. And it is a component that integrates rotation and static, electromagnetic change and mechanical movement, and realizes the conversion of electrical energy and mechanical energy. The dynamic performance of the synchronous motor is very complicated, and its dynamic performance has a great influence on the full electric system. Synchronous motors operate on excitation current. If there is no excitation, the motor is asynchronous. Excitation is a DC system added to the rotor, and its rotation speed and polarity are consistent with those of the stator. 

The current of synchronous motor is ahead of the voltage in phase, that is, the synchronous motor is a capacitive load. In many cases, synchronous motors are used to improve the power factor of the power supply system.

Permanent magnet synchronous motor is an AC motor that generates torque by the interaction of the excitation magnetic field supplied by a direct current and the rotating magnetic field of the armature, and rotates at a synchronous speed. It belongs to AC motors, and the stator windings are the same as synchronous motor. Because its rotor rotation speed is the same as the speed of the rotating magnetic field generated by the stator winding, it is called synchronous motor.

AC motors are divided into two types, synchronous motors and asynchronous motors which are also called induction motors. The biggest difference between synchronous motors and asynchronous motors (induction motors) is whether the speed of rotor is consistent with the speed of the rotating magnetic field in the stator. If the rotor’s rotation speed and the stator’s field speed are the same, it is called synchronous motor; if not, it is asynchronous motor. Furthermore, there are big differences specific to the performance parameters and applications between the two.

The variable frequency drive has the following ten protections on the motor:
Over-voltage protection: The variable frequency drive output has automatic voltage regulator function to control the external overtop power input to be not exceed the motor rated voltage.