Key points for reducing the heating of stepper motors

    As a digital actuator, stepper motors have been widely used in motion control systems. Many friends feel that there is a significant heat generated during the operation of the stepper motor when using it, and they have doubts whether this phenomenon is normal. In fact, heating is a common phenomenon in stepper motors, but what is the normal level of heating and how to minimize the heating of stepper motors?

    Firstly, it is important to understand why stepper motors generate heat. For various stepper motors, the interior is composed of an iron core and winding coils. The winding has resistance, which will cause losses when energized. The magnitude of the losses is proportional to the square of the resistance and current, which is commonly known as copper loss. If the current is not a standard DC or sine wave, harmonic losses will also occur; The iron core has a hysteresis eddy current effect, which can also cause losses in alternating magnetic fields. Its magnitude is related to the material, current, frequency, and voltage, which is called iron loss. Copper and iron losses both manifest in the form of heat generation, thereby affecting the efficiency of the motor.

    Stepping motors generally pursue positioning accuracy and torque output, with relatively low efficiency, high current, and high harmonic components. The frequency of alternating current also varies with the speed. Therefore, stepping motors generally have heating problems, which are more severe than general AC motors. Furthermore, controlling the heating of the stepper motor within a reasonable range mainly depends on the internal insulation level of the motor. The internal insulation performance is only damaged at high temperatures (above 130 degrees Celsius). So as long as the internal temperature does not exceed 130 degrees, the motor will not be damaged, and the surface temperature will be below 90 degrees. So, the surface temperature of the stepper motor is normal between 70 and 80 degrees.