Soft starters and frequency converters are two completely different uses of the product.
The inverter is used for the need for speed control, the output not only change the voltage but also change the frequency;
The soft starter is actually a voltage regulator for the motor to start when the output only changes the voltage and does not change the frequency.
The frequency converter has all the soft starter functions, but its price is much more expensive than the soft starter, the structure is much more complex.
Inverter is better than soft start:
1, on the inverter, is a change in three-phase sine AC frequency of the device;
2, because the DC into a sinusoidal AC waveform, is an irreversible process, or is impossible, can only use the average voltage waveform is a sine wave PWM wide carrier to achieve the purpose of sinusoidal frequency conversion;
3, the average voltage waveform is a sine wave PWM wide carrier, is through the full control device IGBT switch to achieve the role of the inverter output is the width of the periodic changes in the rectangular wave;
4, and the asynchronous motor from the PWM to adjust the wide carrier wave sine wave, and produce a constant electric rotation required magnetic field;
5, and by changing the frequency to change the synchronous speed of asynchronous motor to achieve the purpose of AC motor frequency control.
The biggest difference between the frequency converter and the soft starter is:
1, the soft start is trying to cut the sine wave damage, it is easy, just as water to the lower flow as simple;
2, the inverter is doing everything possible to obtain the frequency adjustable sine wave, it is difficult! It 's as hard as water is going to flow.