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Stepper Motor No Load Start Frequency

Sep 18, 2017

stepper motor No load start frequency

What are the reasons for stepping motor bearing overheating?

A: 1, stepper motor itself:

(1) bearing inner and outer ring with too tight;

(2) parts and geometric tolerances are problems, such as the base, cover, shaft and other parts coaxial degree is not good;

(3) improper selection of bearings;

(4) poor bearing lubrication or bearing cleaning is not clean, grease within the debris;

(5) Shaft current.

2, the use of:

(1) improper installation of the unit, such as the stepper motor shaft and the drag of the device axis coaxial degree requirements;

(2) pulley pull too tight;

(3) bearing maintenance is not good, grease or more than the use of life, dry deterioration. Stepping motor speed problem

Stepper motor has a technical parameter: no-load start frequency, that is, stepper motor in the case of no-load can start the normal pulse frequency, if the pulse frequency is higher than the value of the motor can not start normally, may occur stealing or stall. In the case of a load, the starting frequency should be lower. If you want to make the motor to achieve high-speed rotation, the pulse frequency should be accelerated process, that is, the starting frequency is low, and then according to a certain acceleration to the desired high frequency (motor speed from low speed to high speed). The stepper motor is an open-loop control motor that converts an electrical pulse signal into angular displacement or line displacement. In the absence of out of sync, the motor speed, stop the location depends only on the pulse signal frequency and pulse number is not affected by the load changes, when the stepper motor receives a pulse signal, the motor on the set Direction to a fixed angle (step angle or step angle), by controlling the number of pulses and pulse frequency to control the motor angular displacement and motor speed to achieve accurate open-loop control. In addition, the stepper motor every step of the angle and the theoretical step between the total there is always a certain error, from a certain step to any step, there is always a certain error, but the stepper motor every step of the number of steps The same, without losing the case, the step error will not be long-term accumulation.

The above mentioned are not out of step in the case, how to avoid out of step? First of all we need to know the factors causing the motor out of step:

1, the rotor acceleration is slower than the rotating magnetic field of the stepping motor;

2, the average speed of the rotor is higher than the average rotation speed of the stator magnetic field;

3, the motor load inertia is large;

4, stepper motor resonance.

When the rotor speed is slower than the rotating magnetic field of the stepping motor, the rotor speed is lower than the commutation speed, the motor will be out of step, because the input motor power is insufficient, the torque can not make the rotor speed to keep up with the stator magnetic field rotation speed, Thus causing out of step. The average speed of the rotor is higher than the average rotation speed of the stator magnetic field. This is the time that the stator energizes for a long time, which is longer than the time required for the step. The rotor gets too much energy during the stepping process, resulting in excessive torque Causing the motor to step by step.