Question

How is stepper motor speed controlled?

Answer 1

Stepper motor speed is controlled by adjusting the **frequency** of the pulses sent to the motor's control circuit. Here's a simple breakdown of how it works:

1. **Pulse Timing**: A stepper motor moves in discrete steps, and each step corresponds to one pulse. By increasing the frequency (rate) of the pulses, the motor will turn faster. If the pulse rate is lower, the motor turns slower.

2. **Pulse Rate (Frequency)**: The number of pulses per second determines the speed of the motor. For example:
   - If you send 100 pulses per second, the motor moves 100 steps per second (or 100 steps per second of rotation).
   - If you send 500 pulses per second, the motor will rotate faster.

3. **Control Method**: This pulse rate is often controlled using a **controller** (like a microcontroller or a dedicated stepper motor driver). The controller generates the pulses and adjusts the timing based on the desired speed.

4. **Acceleration/Deceleration**: To avoid mechanical stress or sudden jerks, stepper motors can be gradually accelerated or decelerated by slowly increasing or decreasing the pulse frequency. This ensures smooth motion and prevents damage.

In summary, to control the speed of a stepper motor, you control the **frequency** of the input pulses that drive the motor.