The stepper motor has a technical parameter: no-load starting frequency, that is, the pulse frequency that the stepper motor can start normally under no-load conditions, if the pulse frequency is higher than this value, the motor cannot start normally, and it may lose step or block rotation. In the case of load, the starting frequency should be lower. If you want to make the motor reach high speed rotation, the pulse frequency should have an acceleration process, that is, the starting frequency is low, and then it rises to the desired high frequency according to a certain acceleration (the motor speed rises from low speed to high speed).