What is the working principle of linear motor?

the side of linear motor that evolved from stator is called primary, and the side that evolved from rotor is called secondary. In practical application, the primary and secondary are made into different lengths to ensure that the coupling between the primary and secondary remains unchanged within the required stroke range. Linear motors can be short primary and long secondary, or long primary and short secondary. Considering the manufacturing cost and operating cost, take the linear induction motor as an example: when the primary winding is connected with AC power supply, traveling wave magnetic field will be generated in the air gap, and when the secondary winding is cut by traveling wave magnetic field, electromotive force will be induced and current will be generated, which will interact with the magnetic field in the air gap to generate electromagnetic thrust. If the primary is fixed, the secondary moves in a straight line under the action of thrust; On the contrary, the primary does linear motion. Driving and control technology of linear motor A linear motor application system must not only have a linear motor with good performance, but also have a control system that can meet the technical and economic requirements under safe and reliable conditions. With the development of automatic control technology and microcomputer technology, there are more and more control methods for linear motors.

the research on linear motor control technology can be basically divided into three aspects: one is traditional control technology, the other is modern control technology, and the third is intelligent control technology. Traditional control technologies such as PID feedback control and decoupling control have been widely used in AC servo system. Among them, PID control contains information in the process of dynamic control, which has strong robustness and is the most basic control mode in AC servo motor drive system. In order to improve the control effect, decoupling control and vector control technology are often used. Under the condition that the object model is fixed, unchangeable and linear, and the operating conditions and operating environment are fixed, the traditional control technology is simple and effective. However, in the high-performance situation of high-precision micro-feed, the change of object structure and parameters must be considered. All kinds of time-varying and uncertain factors, such as nonlinear influence, change of operating environment and environmental interference, can get satisfactory control effect. Therefore, modern control technology has attracted great attention in the research of linear servo motor control. Common control methods are: adaptive control, sliding mode variable structure control, robust control and intelligent control. This paper mainly combines fuzzy logic, neural network with PID, H∞ control and other existing mature control methods to learn from each other's strong points to obtain better control performance.