1, the principle of motor heating
The various types of motors we usually see have iron cores and winding coils inside. There is resistance in the winding, and loss occurs when energized. The loss is proportional to the square of the resistance and current. This is the copper loss we often say. If the current is not a standard DC or sine wave, harmonic loss will occur. The core has hysteresis. The eddy current effect also occurs in the alternating magnetic field, and its size is related to data, current, frequency, and voltage. This is called iron loss. Both copper loss and iron loss are expressed in a hot way and then affect the power of the motor. Stepper motors generally seek positioning accuracy and torque output. The power is relatively low, the current is generally large, and the harmonic components are high. The frequency of the alternating current also changes with the rotational speed. Therefore, the stepping motor generally has a fever condition, and the condition is more general. The AC motor is serious.
2, the reasonable range of stepper motor heating
The extent to which the motor heat is allowed depends on the internal insulation level of the motor. The internal insulation properties are destroyed at high temperatures (above 130 degrees). Therefore, the internal motor does not exceed 130 degrees, the motor will not damage the ring, and the surface temperature will be below 90 degrees. Therefore, the stepper motor surface temperature is normal at 70-80 degrees. The simple temperature measurement method is useful for point thermometers. It can also be roughly judged: it can be touched by hand for more than 1-2 seconds, not exceeding 60 degrees; it can only be touched by hand, about 70-80 degrees; It is more than 90 degrees.
