1. Energy saving

All household appliances generate varying degrees of harmonic voltage and current during motor operation, causing the motor to operate under non sinusoidal voltage and current. High order harmonics can cause an increase in stator copper loss, rotor copper (aluminum) loss, iron loss, and additional loss of the motor, with the most significant being rotor copper (aluminum) loss. Because ordinary AC asynchronous motors rotate at synchronous speeds close to the fundamental frequency, high order harmonic voltages can cause significant rotor losses when cutting the rotor bars with a large slip. In addition, additional copper consumption due to Skin effect shall also be considered. These losses will cause the motor to generate additional heat, reduce efficiency, and output power. However, if a variable frequency motor is used, its energy consumption can be reduced by about 20% -30%.

2. Long service life

The carrier frequency of the motor during operation is about several thousand to more than ten kilohertz, which makes the stator winding of the motor bear a high voltage rise rate, equivalent to applying a steep impulse voltage to the motor, making the inter turn insulation of the motor withstand more severe tests. Variable frequency motors can work under the voltage of rectifier filtering, resulting in more stable performance and longer lifespan.

3. Low noise and vibration

The vibration and noise caused by electromagnetic, mechanical, ventilation and other factors in ordinary asynchronous motors become more complex. The various time harmonics contained in the variable frequency power supply interfere with the inherent spatial harmonics of the electromagnetic part of the motor, forming various electromagnetic excitation forces. When the frequency of electromagnetic force waves is consistent or close to the natural vibration frequency of the motor body, resonance phenomenon will occur, thereby increasing noise. Due to the wide operating frequency range and large speed variation range of the electric motor, it is difficult to avoid the natural vibration frequency of various components of the electric motor due to the frequency of various electromagnetic force waves. But variable frequency motors can effectively solve these problems.

4. Can start and brake frequently

Variable frequency motors can solve the problems of efficiency, temperature rise, insulation strength, noise and vibration, cooling, as well as fatigue and accelerated aging of mechanical and insulation structures caused by frequent starting and braking of ordinary asynchronous motors. They can also effectively reduce the instantaneous voltage of the motor during startup.

5. Continuously variable speed

Continuously variable transmission is a gradual increase or decrease in speed from stop to maximum speed, or from maximum speed to stop, without gears. In addition, a fully DC variable frequency motor can be divided into many speed ranges through a frequency converter to control the motor's speed and actual demand. However, the maximum number of speed ranges for AC brush motors is only three, and wind speed regulation cannot achieve the effect of variable frequency.

The advantages of frequency conversion technology are clearly there, but at this stage we do not need to overly pursue frequency conversion products. Because domestic frequency conversion technology is still in its early stages, many promote themselves as products of frequency conversion motors, which have not truly reached the core of frequency conversion technology, just "pseudo frequency conversion", and this money is somewhat unjustified.