2024-03-19 14:06:31

The difference between variable frequency start and soft start of air compressor

Control principle

Air compressor soft start

It is a starting method between star-delta start and variable frequency start. It has more functions than star-delta start and fewer functions than 

variable frequency start. Soft start mainly causes the voltage at the motor end to slowly increase during the starting process, thereby controlling 

the starting current and torque of the motor, so that the motor can start smoothly.


Air compressor frequency conversion start

The principle is to convert the input power supply into an AC power conversion device with adjustable voltage and adjustable frequency, and adjust 

the speed and frequency of the AC motor by adjusting the frequency and voltage.

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Control function

Soft start mainly adjusts the starting voltage of the motor so that the motor starts smoothly to reduce the impact on the power grid and machinery.

Variable frequency starting can not only reduce the impact on the power grid and machinery, but also adjust the frequency and motor speed.

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Summarize

The application scope of variable frequency start is wider than that of soft start. Variable frequency start covers the advantages of soft start, 

and has functions such as adjusting frequency and speed, reducing noise, etc. that soft start does not have. All in all, the function of variable frequency start is far better than that of soft start.