The maximum surface temperature of the step motor is permissible
Reduce the heat of the motor Reducing heat is the reduction of copper damage and iron loss. Reduce copper loss, there are two directions, resistance and current, choose as far as possible when this request in the selection of small resistance and the rated current of motor, KaiFu electronic engineers advice is: the two-phase motor, motor without parallel in tandem. But this often contradicts the demands of the moment and the high speed. For motor has been selected, should make full use of the drive of automatic flow control function and offline function, the former automatically reduce current when motor is static, the latter will be the current be cut altogether. In addition, the breakdown drive is due to the current waveform, which is close to the sine wave, less harmonic, and less electric motor. There are few ways to reduce iron loss, and the voltage level is associated with high speed, but it also leads to increased heat. Therefore, it should choose the appropriate driving voltage level, which is high speed, stability and heat, noise and so on.
Control the stepping motor in reasonable range The degree to which the electric motor can be heated depends on the internal insulation level of the motor. Internal insulation can be damaged at high temperature (130 degrees). So as long as the internal is not more than 130 degrees, the motor will not be damaged, and the surface temperature will be below 90 degrees. As a result, the surface temperature of the stepping motor is normal at 70-80 degrees. A simple temperature measuring method is useful for a thermometer, and it is also a rough judgement: you can touch one to two seconds with your hand, not exceeding 60 degrees. You can only touch it with your hands, it's about 70 to 80 degrees. A few drops of water quickly vaporize, and more than 90 degrees; You can also use a temperature gun
The effects of fever Electric motor fever, although not normally affecting the life of the motor, is not necessary for most customers. However, severe fever can have some negative effects. Internal parts such as motor thermal expansion coefficient of different lead to the change of structural stress and internal air gap of tiny change, affects the dynamic response of the motor, high speed will be easy to out of step. In some cases, excessive heating of electric motors, such as medical devices and high-precision testing equipment, are not allowed. Therefore, the heating of the motor should be controlled.
The highest temperature on the outside can be determined according to the quality of each brand, normally 70 to 80 degrees is normal. First, you need to understand why the step motors heat up For all kinds of stepping motors, the interior is composed of iron core and winding coils. Winding resistance, electricity will produce loss, the loss is proportional to the square of the size and the resistance and current, this is the copper loss, we often say that if the current is not a standard dc or sine wave, will also produce harmonic loss; The core has a hysteresis vortex effect, which also produces loss in the alternating magnetic field, which is related to material, current, frequency and voltage, which is called iron loss. Copper damage and iron loss are shown in the form of fever, which affects the efficiency of the motor. Stepper motor general pursuit of position precision and torque output, the efficiency is low, the current is compared commonly big, high harmonic components, the frequency of the alternating current is also change with speed, thus stepping motor are widespread fever, than the general ac motor serious condition.
