Analysis of the reasons for the inaccurate positioning of stepper motor

Analysis of the reasons for the inaccurate positioning of the stepper motor:

1) The general stepper driver has certain requirements for direction and pulse signal. For example, the direction signal is determined a few microseconds before the arrival of the first pulse rising edge or falling edge (different driver requirements), otherwise it will be The angle at which a pulse operates is opposite to the actual required steering. Finally, the fault phenomenon appears to be more and more biased, and the smaller the subdivision is, the more obvious the solution is. The solution mainly uses software to change the logic or delay of the pulse.

2) Due to the characteristics of the stepping motor, the initial speed cannot be too high. Especially when the load inertia is large, it is recommended that the initial speed be below 1r/s, so that the impact is small, and the same acceleration is too large. The rush causes the positioning to be inaccurate; there should be a certain pause time between the forward and reverse rotation of the motor, and if not, the overshoot will be caused by the reverse acceleration being too large.

3) Adjust the value of the compensated parameter according to the actual situation. (Because the elastic belt has a large elastic deformation, it needs to be compensated when changing the direction).

4) Properly increase the motor current and increase the motor driver voltage (note the optional driver) to select a motor with a higher torque.

5) The disturbance of the system causes the malfunction of the controller or the stepper motor driver. We can only find a way to find the source of interference, reduce its interference ability (such as shielding, increase the separation distance, etc.), cut off the transmission route, and improve its own resistance. Interference ability, common measures:

1 Replace the ordinary wire with a double-shield shielded wire. The signal wire in the system is separated from the high-current or large-voltage-changing wire to reduce the electromagnetic interference capability.

2 Use the power filter to filter out the interference wave from the power grid. Under the condition of permission, the power supply filter is added to the input end of each large power equipment to reduce the interference between the equipments in the system.