Why is the current of the motor with load larger than that without load?Because of this, people began to use their brains to solve this problem and invented soft boot.
Soft start, as the name suggests, is not directly started, but slowly, bit by bit start. For example, bit by bit at the input end of the motor
The voltage rises from 0 to the rated voltage, and the frequency gradually changes from 0 to the rated frequency, so that the starting current of the motor in the starting process will be changed from the past uncontrollable overload impulse current to a controllable one that can be adjusted according to needs.Small starting current. There is no impact torque in the whole process of motor start-up, but smooth start-up operation. This is called the soft start of the motor.
At present, there are two methods of soft start, one is to use a special soft starter to achieve soft start; One is to use inverter control to achieve soft start. And the old method of traditional soft launch has been used by few people. I won't go over it here. Soft starters and frequency converters are two completely different products. The frequency converter is used where speed regulation is required, and its output not only changes the voltage but also changes the frequency. The soft starter is actually a voltage regulator, used when the motor starts, the output only changes the voltage and does not change the frequency. The frequency converter has all the functions of the soft starter, but its price is much more expensive than the soft starter, and the structure is much more complex.