A brief introduction of the principle of step motor
Issuing time:2018-02-03 00:00
The so-called step motor is an actuator that transforms electrical pulses into angular displacement; more commonly, when the step driver receives a pulse signal, it drives the stepper motor to rotate a fixed angle in the set direction. We can control the angular displacement of the motor by controlling the number of the pulse, so as to achieve the goal of precise positioning. At the same time, we can control the speed and acceleration of the motor by controlling the pulse frequency, so as to achieve the purpose of speed regulation. At present, the commonly used stepper motors include reactive step motor (VR), permanent magnet stepper motor (PM), hybrid stepping motor (HB) and single-phase stepper motor.
The difference between the stepping motor and the common motor is mainly in the form of its pulse drive. It is this characteristic that the stepping motor can be combined with the modern digital control technology. But the stepper motor is not as good as the traditional closed loop control DC servo motor in the control precision, speed range and low speed performance, so it is mainly used in the situation that the precision is not very high. Stepping motor has the characteristics of simple structure, high reliability and low cost, so the step motor is widely used in various fields of production practice. Especially in the field of CNC machine tool manufacturing, because the step motor does not need A/D conversion, it can directly convert digital Mai Chongxin into angular displacement, so it has been recognized for all the time. It is the most ideal actuator for CNC machine tools.
In addition, there are many defects in the stepping motor, and the stepping motor can operate at low speed, but it can not start at a certain speed, but if it is higher than a certain speed, the step motor can not start with a sharp whistle. The precision of the subdivision drive of different manufacturers may be very different, the greater the precision of the fine fraction, the more difficult to control the control. And when stepping motor rotates at low speed, it has greater vibration and noise.
Although stepping motors have been widely applied, stepper motors cannot be used as conventional DC motors, and AC motors are used routinely. It must be composed of two loop pulse signal, power drive circuit and other control systems. So stepping motor is not easy. It involves many professional knowledge such as machinery, motor, electronics and computer.
At present, there are many manufacturers of stepping motor, but with professional technicians, it can be developed by themselves, the manufacturers are very small, most of the manufacturers only one or twenty people, even the most basic equipment is not. It is only in a blind imitation stage. This will cause many troubles to users in product selection and use.