The reason why the stepper motor is loud

When we use the stepper motor, we often find that the sound of the motor will be abnormal or with vibration, so what is the buzz of the stepper motor, and what is the reason for the large vibration and noise? Why the noise? How to eliminate the noise? Is it the quality of the product itself, or will we use an incorrect driving method? What are the specific reasons and how to solve them?

When driving the stepper motor, we elaborate from two aspects:

A: When the stepper motor is at rest

If there is an obvious noise inside, it is somewhat similar to the rapid change of the coil, which is generally caused by excessive coil current. In this case, the most effective solution is to reduce the current flowing through the motor coil, including setting the driver to automatically half-current when the motor stops and reducing the drive current of the motor. Because of the working mode of the stepper motor, the state of the stepper motor is in, and the internal coil has a current change.

B: When the stepper motor is in motion, if the noise and vibration of the stepper motor are found to be obvious, it should be checked according to the following steps:

1. Whether the stepper motor and the driver are compatible: If they are not compatible, the adjustment subdivision, drive current, and speed of some of the following steps are likely to be wasted efforts. In the selection of stepper motor and driver, it is best to buy a complete set, each company's products are generally tested, so there will be no product compatibility. The owner of the motor west drive, often bring unexpected trouble, because the quality of each product is no problem, but there is a problem of incoordination, you want to change are unable to deal with.

2, with the progress of science and technology, the traditional driver has gradually transformed from analog to digital, the reasons are still there, the analog in the drive stepper motor noise is larger, and the digital basically no. The reason is roughly that a DSP chip is added to the digital one to optimize the stepper motor drive. Therefore, if you want to ensure that noise and vibration are as small as possible, it is recommended to use digital stepper motor drivers.

3. Correctly adjust the subdivision and current of the stepper motor driver. The greater the subdivision, the smaller the variation of the coil in the motor, which reduces the noise. Subdivision is generally recommended to set at 8 subdivisions and above, if the use of table lookup method to achieve acceleration and deceleration and uniform speed calculation, control, for the general MCU, are easily competent. In order to ensure that the stepper motor has enough torque to drive the load, the drive current should also be minimized, the smaller the parameter is set, the same motor coil current change amplitude is smaller. This step is very important, often some engineers do not pay much attention, thinking that the quality is wrong, in fact, the subdivision and current did not get it right.

4, the correct setting of stepper motor acceleration and deceleration speed and maximum operating speed. The experiment shows that the stepper motor is more likely to produce additional noise during acceleration and deceleration. The solution is to ensure that the acceleration and deceleration of the stepper motor does not lose step, and the acceleration and deceleration speed of the stepper motor can be appropriately increased. In the case of light load, the acceleration and deceleration of the stepper motor should be controlled within 1S, otherwise it will hear the noise caused by the change of the drive current frequency when the motor is accelerating and decelerating. When setting the maximum operating speed, it is necessary to consider whether the motor torque is sufficient to drive the load, and whether it will resonate with the connected mechanical structure at this speed.

The main reasons for the loud sound of the stepper motor and the solutions above, of course, some have to be checked one by one according to the actual application environment, if you encounter similar problems can not clearly understand the reason, you can call our engineers for consultation!