What is a Stepper Motor? What is a Stepper Motor Driver?

A stepper motor is a specialized motor designed for control purposes. It operates in fixed angles, known as "step angles," moving step by step. One of its key features is the absence of cumulative error (100% accuracy), making it widely used in various open-loop control applications.

A stepper motor requires an electronic device for operation, which is the stepper motor driver. The driver converts the pulse signals from the control system into angular displacement of the stepper motor. In other words, for each pulse signal sent by the control system, the driver causes the stepper motor to rotate by one step angle. The motor's speed is directly proportional to the frequency of the pulse signal.

By controlling the frequency of the pulse signals, precise positioning of the motor can be achieved.

What is the "Phase Number" of a Stepper Motor, and How Should I Choose the Right One?

The phase number of a stepper motor refers to the number of coil groups inside the motor. Common options include 2-phase, 3-phase, 4-phase, and 5-phase stepper motors. The step angle varies with the phase number: for example, a 2-phase motor typically has a step angle of 0.9°/1.8°, a 3-phase motor has 0.6°/1.2°, and a 5-phase motor has 0.36°/0.72°.

When using a non-microstepping driver, users rely on selecting different phase numbers to meet their step angle requirements. However, with a microstepping driver, the phase number becomes less significant, as users can adjust the microstepping settings on the driver to modify the step angle.

What are the Advantages of Microstepping, and Why Do We Recommend Using It?

1. Eliminates Low-Frequency Oscillation:
   Low-frequency oscillation is an inherent characteristic of stepper motors (especially reactive motors). Microstepping is the only way to eliminate it. If your stepper motor operates in resonance regions (e.g., during circular motions), a microstepping driver is essential.

2. Increases Motor Output Torque:
   Microstepping improves the motor’s output torque.

3. Enhances Motor Resolution and Efficiency:
   By reducing the step angle and increasing step uniformity, microstepping improves the motor’s resolution, which is a significant qualitative improvement.

These advantages, particularly in terms of performance, represent a leap forward rather than a mere incremental improvement. Based on our records, most users who previously used non-microstepping drivers have switched to microstepping drivers after making comparisons. Therefore, we strongly recommend choosing a microstepping driver.

Positioning Issues

If the motor does not position correctly, try the following common solutions:

1. Signal Interference: Eliminate interference sources.

2. Grounding Issues: Ensure the shielding ground is properly connected.

3. Broken Motor Wires: Check and reconnect wiring properly.

4. Microstepping Settings: Verify and adjust the microstepping configuration.

5. Low Current Setting: Increase the current as needed.

6. Pulse Direction Timing Issue: Adjust the pulse edge to ensure proper timing.

7. Loose Motor-Load Connection: Check and secure the motor-to-load connection.

Motor Stalling Issues

If the motor stalls, consider the following solutions:

1. Short Acceleration Time: Increase the acceleration time.

2. Insufficient Torque: Choose a motor with higher torque.

3. Low Voltage or Current: Increase the voltage or current appropriately.

4. Motor-Load Misalignment: Align the motor shaft and load to ensure concentricity.

If the above methods do not resolve your issue, please add our WeChat ID STEP_CustomerCare to contact SDP customer service. We will do our utmost to provide technical support and assistance.