The history of linear motors dates back to the early 1840s, when Wheaton developed small, unsuccessful linear motors. Over the next 160 years, the technology went through three major phases: experimental exploration, development and application, and commercialization. From 1971 to the present, linear motors have entered a stage of independent application. Their use has expanded rapidly, leading to the creation of various devices such as steel pipe conveyors, coal conveyors, electric doors, and windows. Moreover, magnetic levitation trains powered by linear motors have achieved speeds exceeding 500 km/h, approaching the speed of aircraft. In China, research on linear motors began in the early 1970s. Current applications include factory drives, electromagnetic hammers, and punching machines. Despite some progress, China still lags behind other countries in terms of widespread application and commercialization. Many domestic institutions are now paying more attention to this field [1]. The integration of linear motors into CNC machine tools has gained significant popularity worldwide. This is driven by the need for high-speed machining to improve efficiency and part quality. Traditional "rotary motor + ball screw" systems have limitations, with maximum feed speeds around 30 m/min and accelerations of only 3 m/s². In contrast, linear motor-driven systems offer speeds up to 30 times faster, accelerations 10 times greater (up to 10g), and seven times higher stiffness. They also eliminate backlash and provide high-frequency response due to low inertia. In 1993, Germany's ZxCell-O introduced the first linear motor-driven HSC-240 high-speed machining center, achieving a spindle speed of 24,000 rpm and a feed rate of 60 m/min. The U.S. followed with the HVM-800, reaching 20,000 rpm and 75.20 m/min. Japan has since developed various linear motor-based machines, including high-speed and ultra-precision equipment [1]. In China, Zhejiang University developed a linear motor-driven press, while Nanjing Sikai launched a self-developed digital linear motor lathe. At the 2003 China International Machine Tool Exhibition, Beijing Electric Power High-Tech showcased a linear motor-driven machining center with a spindle speed of 15,000 rpm. A linear motor converts electrical energy directly into linear motion without intermediate mechanisms. It can be viewed as a radial-cut rotary motor laid out flat. The stator side is called the primary, and the rotor side is the secondary. Typically, the primary is shorter to reduce costs and ensure consistent coupling over the travel range. The working principle of a linear motor is similar to that of a rotary motor. In an induction motor, an AC power source creates a traveling magnetic field, inducing current in the secondary, which interacts with the magnetic field to generate thrust. If the primary is fixed, the secondary moves linearly. Linear motor control systems must be reliable and efficient. Traditional techniques like PID and vector control are widely used, while modern methods such as adaptive control and robust control are gaining traction. Intelligent control, including fuzzy logic and neural networks, is also being explored to enhance performance. Examples of linear motor applications in CNC machines include high-frequency feed units for non-circular parts and open CNC systems using PC-based controllers. These systems integrate motion control cards, such as the PCI-8132, to drive linear motors with precision and flexibility. In conclusion, linear motor-driven high-speed machining centers are becoming a key focus for global manufacturers, with applications in automotive and aerospace industries. While the technology is advancing, China still faces challenges in full-scale adoption. Further research is needed to address technical issues and expand practical applications.

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