My country is a major producer of permanent magnet materials, particularly rare earth permanent magnets such as neodymium iron boron (NdFeB). my country's rare earth reserves are approximately four times the total reserves of all other countries combined, earning it the title of "Rare Earth Kingdom." Research and development in rare earth permanent magnet materials and motors has reached international advanced levels. Therefore, permanent magnet synchronous motors have excellent application prospects in my country. Fully leveraging my country's abundant rare earth resources and vigorously researching and promoting the application of various permanent magnet motors, represented by rare earth permanent magnet motors, has significant theoretical and practical value for realizing my country's socialist modernization.
With the improvement in permanent magnet performance and the decrease in price, as well as the advantages brought by replacing the excitation windings in wound rotors with permanent magnets-such as no rotor overheating, simpler control systems, higher operating efficiency, and higher operating speeds-permanent magnet synchronous servo motors have been widely used in low-power applications such as CNC machine tools and robots.
In recent years, with the continuous improvement and refinement of permanent magnet material performance, especially the improved thermal stability and corrosion resistance of neodymium iron boron permanent magnets and their gradual price reduction, coupled with the further development of power electronic devices and the gradual maturation of research and development experience in permanent magnet motors, and through vigorous promotion and application of existing research results, permanent magnet motors have found increasingly widespread applications in national defense, industrial and agricultural production, and daily life.
They are developing towards higher power (high speed, high torque), higher functionality, and miniaturization. The single-unit capacity of rare-earth permanent magnet motors has exceeded 1000KW, the highest speed has exceeded 300,000 r/min, the lowest speed is below 0.01 r/min, and the smallest motor has an outer diameter of only 0.8mm and a length of 1.2mm.
1. High Efficiency and High Power Density
The energy efficiency of permanent magnet motors is typically higher than 90%, and in some high-performance applications, it can even reach over 95%. Their high power density allows them to provide stronger power output within the same volume and weight. This means that permanent magnet motors can better meet the needs of space-constrained applications.
2. Excellent Starting Performance
Due to the presence of permanent magnet material in its rotor, permanent magnet motors can quickly reach rated speed during startup, and possess enormous starting torque. This characteristic makes them an ideal choice in electric vehicles, industrial automation equipment, and other fields.
3. Low Noise and Low Vibration
Permanent magnet motors exhibit relatively low operating noise and vibration. This is because their structure is relatively simple, lacking easily worn parts such as slip rings and brushes, resulting in lower maintenance costs and making them more suitable for noise-sensitive applications, such as household appliances and medical equipment.
4. Applicability to Closed-Loop Control Systems
Permanent magnet motors can be seamlessly integrated with modern digital control technology to achieve precise closed-loop control. This gives them a significant advantage in fields requiring high precision and high responsiveness, such as robotics and CNC machine tools.