Aug 10, 2017
The stepper motor is a kind of discrete motion device, Hybrid Stepper Motor which has the essential relation with the modern digital control technology. In the current domestic digital control system, stepper motor is widely used. With the advent of all-digital AC servo system, AC servo motor is used in digital control system more and more. In order to adapt to the development trend of digital control, most of the motion controlling system adopts stepper motor or all-digital AC servo motor as executive motor. Although the two are similar in control mode (pulse string and directional signal), there is a great difference in performance and application. Hybrid Stepper Motor The use performance of the two is compared.
Two-phase hybrid stepper motor step angle is generally 3.6 °, 1.8 °, five-phase hybrid stepper motor step angle is generally 0.72 °, 0.36 °. Hybrid Stepper Motor There are also some high-performance stepper motor step angle smaller. For example, the company produces a stepper motor for walking wire machine tool, its step angle is 0.09 °; German hundred-Grid company (BERGER LAHR) production of three-phase hybrid stepper motor its step angle can be set by dialing switch to 1.8 °, 0.9 °, 0.72 °, 0.36 °, 0.18 °, 0.09 °, 0.072 °, 0.036 °, compatible with two phase and five-phase hybrid stepper motor step angle.
The control accuracy of AC servo motor is ensured by the Rotary encoder of the back end of the motor shaft. Taking Panasonic full digital AC servo motor as an example, for the motor with standard 2500-wire encoder, Hybrid Stepper Motor the pulse equivalent of 360°/10000=0 036° is used in the internal drive with four times frequency doubling technique. For a motor with a 17-bit encoder, Hybrid Stepper Motor the drive takes 217 = 131,072 Pulse motors per receiving cycle, i.e. the pulse equivalent is 360°/131072=9.89 seconds. It is 1/655 of the pulse equivalent of the stepper motor with a step angle of 1.8 °.
The low frequency vibration phenomenon is easy to appear in the stepper motor at low speed. The vibration frequency is related to the load condition and the drive performance, generally believed that the vibration frequency is half of the motor no-load Take-off frequency. Hybrid Stepper Motor The low-frequency vibration which is determined by the working principle of the stepper motor is very unfavorable to the normal operation of the machine. When the stepper motor works at low speed, the damping technique should be used to overcome the low-frequency vibration, such as adding dampers to the motor, or using subdivision technology on the drive.
AC servo motor is running very smoothly, even at low speed will not appear vibration phenomenon. The AC servo system has resonance suppression function, Hybrid Stepper Motor which can cover the rigidity of the machine, and the system has the frequency analytic function (FFT), which can detect the resonance point of the machine, and facilitate the adjustment of the system.
Stepper motor generally does not have overload capacity. Hybrid Stepper Motor AC Servo motor has strong overload capacity. Taking Panasonic AC servo system as an example, it has the capability of speed overload and torque overload. The maximum torque is three times times of the rated torque and can be used to overcome the inertia moment of inertia load at start-up moment. Stepper motor Because there is no such overload capacity, Hybrid Stepper Motor in the selection in order to overcome this inertia moment, often need to select a larger torque of the motor, and the machine during the normal operation of the time does not need so much torque, there is a phenomenon of moment waste.