Handling Stepper Motor Operation Under High Inertia and Low Speed Conditions

It is indeed very challenging for a stepper motor to operate under high inertia and low speed conditions without a gearbox. At low speeds, cogging torque can cause uneven, jerky motion, similar to the movement of a clock hand. In such applications, attempting to increase the holding current (e.g., from 50% to 75%) via closed-loop control and appropriately raising the position loop Kp gain can bring some improvement, but the effect is likely to be limited.

Note: Only closed-loop series drives can have this parameter modified via software; this operation is not available for open-loop drives.

Using the T-series closed-loop stepper drive as an example:

Open the parameter list.

• Position Loop Gain

• Closed-Loop Holding Current

After modifying the parameters, send and save them to apply the changes.

Under these circumstances, the optimal solution is to add a gearbox.

The advantages of adding a gearbox are as follows:

1. Inertia Matching: The gearbox reflects the high load inertia to the motor side, significantly reducing its impact. This makes the system more responsive and control more stable.
2. Torque Amplification: A core function of the gearbox is to amplify the output torque, multiplying it. This allows the system to easily overcome the motor's cogging torque and load resistance, ensuring smooth startup and operation.
3. Increased Motor Operating Speed: With a gearbox, the motor itself can operate in the mid-to-high speed range where its performance characteristics are better. This perfectly avoids the issues of pronounced cogging torque and high vibration at low speeds. The motion is then reduced by the gearbox to the desired low output speed, resulting in smooth movement.

Updated on: 30/10/2025