Nanyang explosion-proof motor | Differences between asynchronous motor and variable frequency motor

2023-11-22 00:54:25

The manufacturer of explosion-proof motors in Nanyang stated that motors have deeply entered our days, and it can be said that they are ubiquitous, while asynchronous motors are relatively widely used.

We all know that ordinary asynchronous motors can only operate under AC380V/50HZ conditions and can operate under standard sine waves. Its fundamental feature is that the rotor winding does not need to be connected to other power sources, and the stator current is directly taken from the communication power system; Compared with other motors, asynchronous motors have a simple structure, are easy to manufacture, use, and maintain, have high operational reliability, light weight, and low cost. Some people say that a variable frequency motor is just an addition of a frequency converter to an asynchronous motor, and it can work anyway. It seems that their working principle is correct to say this, but in fact, it is not. The various policy plans for variable frequency motors are different from ordinary asynchronous motors.

The impact of frequency converters on motors:

1. The power and temperature rise of electric motors

2. Insulation strength issues of electric motors

3. Harmonic Electromagnetic Noise and Trembling

4. The adaptability of electric motors to frequency recommendations and braking

5. Cooling issues at low speeds

The manufacturer of explosion-proof motors in Nanyang stated that they only need to overcome these problems in order to operate normally. In order to achieve higher efficiency of variable frequency motors, people need to overcome many problems and control the operation status of the motor through the influence of frequency converters. Due to its wide operation plan, it can operate for a long time within the 0.1HZ~130HZ planning range. The PWM width modulation wave output by the frequency converter mimics sinusoidal communication electricity, containing many harmonics. Improper handling can seriously affect the lifespan of the motor.

In terms of structural planning, due to the high impulse voltage of the winding, it is necessary to strengthen the strength of ground insulation and wire turn insulation. The vibration and noise of the motor should consider the rigidity of the motor components and the overall structure to avoid resonance with various force waves. When cooling, the main motor should be selected. The cooling fan has an independent motor drive. In terms of electromagnetic planning, it is necessary to reduce the stator resistance, that is, to reduce the fundamental copper loss to compensate for the copper loss caused by higher harmonics. To suppress the higher harmonics in the current, the inductance of the motor should be appropriately added to ensure impedance matching throughout the entire speed regulation plan. Only by achieving these can we meet the rigid requirements of variable frequency motors.

Asynchronous motors and variable frequency motors each have their own characteristics. In order to choose motors more reasonably, a series of conditions such as work methods, practical work environments, etc. need to be considered. Due to the mechanical structure of variable frequency motors, the planning of electrical parameters is different from that of asynchronous motors. According to stricter operating methods and requirements, the probability of using variable frequency motors is higher, but the cost is higher.

The above information was compiled and released by the Nanyang explosion-proof motor manufacturer. Thank you for watching.