The difference between subdivision and non-subdivision of stepper motor drive
The difference between subdivision and non-subdivision of stepper motor driver: High precision of subdivision drive.
Subdivision is a stepper motor driver will be issued by the superior device each pulse according to the stepper motor driver set subdivision factor into a factor of pulse output.
Analogy stepper motor each turn for 200 pulses, if the stepper motor driver subdivision for 32, then the stepper motor driver needs to output 6400 pulses stepper motor to turn a turn.
Usually stepper motor subdivision has 2, 4, 8, 16, 32, 62, 128, 256, 512….
In foreign countries, for stepper motor system, mainly using two-phase hybrid stepper motor and the corresponding subdivision stepper motor driver. But in the country, the majority of users on the “subdivision” is not particularly well understood, some just think that subdivision is to improve the stepper motor accuracy, in fact, subdivision is mainly to improve the operating performance of stepper motors, is explained as follows.
Subdivision control of the stepper motor is achieved by the stepper motor driver to precisely control the phase current of the stepper motor, to two-phase stepper motor, for example, if the rated phase current of the stepper motor is 3A, if the use of conventional stepper motor driver (such as the commonly used constant current chopper method) to drive the stepper motor, the stepper motor each step of operation, the current in its winding will be a sudden change from 0 to 3A or from 3A sudden change to 0.
The huge change in the stepper motor phase current will inevitably cause vibration and noise in the stepper motor operation. If the use of subdivision stepper motor driver, in the state of 10 subdivision drive the stepper motor, stepper motor each micro-step operation, the current change in its winding only 0.3A instead of 3A, and the current is a sinusoidal curve law changes, which greatly improves the stepper motor vibration and noise, therefore, the advantages in performance is the real advantage of subdivision.
As subdivision stepper motor driver to accurately control the phase current of the stepper motor, so the stepper motor driver to have quite high technical requirements and process requirements, the cost will also be higher.
Note that some domestic stepper motor drivers use “smooth” to replace the subdivision, some are also called subdivision, but this is not the real subdivision, hope that the majority of users must distinguish the essential difference between the two: 1.
1, “smoothing” does not precisely control the phase current of the stepper motor, only the current rate of change to slow down some, so “smoothing” does not produce micro-steps, and subdivision of the micro-steps can be used to precisely determine the position.
2. The phase current of the stepper motor is smoothed, will cause a decrease in stepper motor torque, while the stepper motor driver subdivision control will not only cause a decrease in stepper motor torque, on the contrary, stepper motor torque will increase.