Stepper Motor Electromagnet principle
Stepper motor, also known as pulse motor, based on the most basic electromagnet principle, it is a free rotation of the electromagnet, the action principle is to rely on changes in air gap to produce electromagnetic torque. The original model is derived from years to years. An attempt has been made for the purpose of control for use in the electrode delivery mechanism of a hydrogen arc lamp. This is considered to be the first stepper motor. At the beginning of the twentieth century, stepper motors were widely used in telephone automatic switches. As the Western capitalist powers compete for colonies, stepper motors are widely used in independent systems such as ships and aircraft lacking AC power. The invention of the transistor in the late 1950s was also gradually applied to stepper motors, which became easier for digital control. In the eighties, due to the low-cost microcomputer to multi-functional posture, stepper motor control more flexible and diverse.
The biggest difference between a stepper motor and other control applications is that it receives the digital control signal and converts it into a corresponding angular or linear displacement, which itself is an actuator that performs digital mode conversion. And it can be open-loop position control, enter a pulse signal to get a specified position increment, so that the so-called incremental position control system compared with the traditional DC control system, its cost is significantly reduced, almost no system adjustment. The angular displacement of the stepper motor is strictly proportional to the number of pulses entered and is synchronized with the pulse in time. So as long as the control of the number of pulses, frequency and motor winding phase sequence, you can get the required corner, speed and direction.
China's stepper motor started in the early 1970s, the mid-seventies to the mid-eighties for the finished product development stage, new varieties and high-performance motor continue to develop, at present, with the development of science and technology, especially Permanent magnet materials, semiconductor technology, the development of computer technology, stepper motor in many areas has been widely used.
Stepping Motor Control Technology and Development
As a special motor for control, the stepper motor can not be directly connected to the DC or AC power supply, you must use a dedicated drive power stepper motor driver. In the microelectronics technology, especially the development of computer technology before the controller pulse signal generator is completely implemented by the hardware, the control system uses a separate component or integrated circuit to form a control loop, not only the installation of complex installation, to consume a large number of components, and once the stereotypes , To change the control program must be redesigned circuit. This makes it necessary to develop different drives for different motors. The difficulty of development and the development cost are very high, and the control is more difficult, which limits the promotion of stepper motor.
As the stepper motor is a device that converts electrical pulses into discrete mechanical motion, it has good data control characteristics. Therefore, the computer becomes the ideal driving source of stepper motor. With the development of microelectronics and computer technology, hardware and software Combined with the control method has become the mainstream, that is, through the program to generate control pulses, drive hardware circuit. SCM through the software to control the stepper motor, better dig out the potential of the motor. Therefore, the use of single-chip control stepper motor has become an inevitable trend, but also meet the trend of digital era