Application of servo motor in numerical control
3.1 Application characteristics of servo motor in numerical control system
AC servo motor is a kind of brushless motor, but it is divided into synchronous and asynchronous motor. Synchronous motor is more common in motion control, because it can achieve a lot of power, in the case of the highest rotation, speed It is low and rapidly decreases with increasing power, making it suitable for applications with low speed and smooth operation. Therefore, the high precision, wide speed range, high torque output at low speed, fast response and no overshoot is its biggest feature.
3.2 servo motor has advantages over other motors
AC servo motors perform better than stepper motors in many respects. Although stepper motors are often used to perform motors in some special occasions or in some less demanding situations, AC servo motors are still the most widely used. The motor, then what is the difference between the stepper motor?
One is different in control accuracy. The control precision of the AC servo motor is guaranteed by the rotary encoder at the rear end of the motor shaft, while the two-phase stepping motor is generally 3.6 degrees and 18 degrees, and the five-phase hybrid stepping motor has a distance of 0.72 degrees and 0.36 degrees.
Second, the difference in low frequency characteristics. Stepper motors are prone to low frequency vibration at low speeds. Due to the characteristics of the working principle of the stepper motor, the phenomenon of low frequency vibration is determined, and this phenomenon is harmful and unfavorable for the normal operation of the machine, but the operation of the AC servo motor is very stable, even at very low At speed, it also maintains smoothness without vibration. That is because the AC servo system has a function of resonance suppression, and there is a frequency analysis function inside the system, and when it is detected that the machine has a resonance point, it is adjusted as appropriate.
There are also differences in the characteristics of the moment frequency, the overload capability, and the running performance and speed response performance. In the design process of the control system, it is necessary to comprehensively consider the requirements of control, cost, and many other factors, and select the appropriate control motor in a timely manner.
