The development and application of rare-earth permanent magnet synchronous motors have expanded the use of permanent magnet synchronous motors across various industries. The most notable performance characteristics of rare-earth permanent magnet motors are lightweight design, high performance, and high energy efficiency.
High-performance rare-earth permanent magnet motors form the foundation for numerous new technologies and high-tech industries. When integrated with power electronics and microelectronic control technologies, they enable the production of diverse mechatronic products with outstanding performance, such as CNC machine tools, machining centers, flexible production lines, robots, electric vehicles, high-performance home appliances, computers, and more. As rare-earth permanent magnet motor technology continues to advance, the industry is gradually exhibiting the following development trends!
I. Advancing Toward High Energy Efficiency
Rare earth permanent magnet motors are inherently energy-efficient products, achieving average electricity savings exceeding 10%. Specialized rare earth permanent magnet motors can deliver savings as high as 15% to 20%.
Motor energy efficiency improvement occurs in two ways. First, reforming the structure of asynchronous motors enhances efficiency and other performance characteristics. Asynchronous motors are widely used across industrial production due to their simple structure, low cost, and adaptability to various operating conditions. Second, developing permanent magnet synchronous motors achieves even greater energy savings.
Internationally, the primary approach to enhancing motor efficiency involves optimizing asynchronous motor designs: increasing the use of effective materials like copper, aluminum, and electrical steel sheets to reduce winding and iron losses; employing superior magnetic materials and processes to lower iron losses; rationally designing ventilation structures and selecting high-performance bearings to minimize mechanical losses; and reducing stray losses through improved design and manufacturing techniques. High-efficiency asynchronous motors have already been developed abroad. Given China's national conditions, high-performance rare-earth permanent magnet materials have achieved industrialization. China now leads the world in neodymium-iron-boron production, and its pricing has become more reasonable. Therefore, developing permanent magnet synchronous motors represents one of the technological trends in the new century's motor industry.
II. Advancing Toward Mechatronics
To elevate the level of traditional electromechanical products, we must firmly grasp the mechatronics approach. The foundation for achieving mechatronics lies in developing various high-performance rare-earth permanent magnet motors required for mechatronic applications, such as servo motors for CNC machine tools and VCM voice coil motors for computers. A 60-tool machining center requires 30 servo motors. Variable-frequency speed-regulated rare-earth permanent magnet synchronous motors and brushless DC motors form the cornerstone of mechatronics.
III. Advancing Toward High Performance
Modern equipment imposes diverse high-performance demands on the motor industry. Military applications require high-performance signal motors, mobile power stations, and servo systems/motors for automation equipment. Aerospace sectors demand high-performance, highly reliable permanent magnet motors. Chemical fiber machinery necessitates variable-frequency synchronous motors with high speed regulation accuracy. CNC machine tools, machining centers, and robots require rare-earth permanent magnet servo motors with high speed ratios. Computers need high-precision oscillating motors and spindle motors, among others.
IV. Development Toward Specialized Motors
The loads driven by motors vary immensely. Relying solely on general-purpose motors can be technically and economically inefficient in certain scenarios. Consequently, foreign countries vigorously develop specialized motors, which account for approximately 80% of total production, while general-purpose motors make up only 20%. In China, the situation is reversed: specialized motors constitute just 20% of production, with general-purpose motors dominating at 80%. Specialized motors are engineered for specific load characteristics. For instance, rare-earth permanent magnet motors designed for oilfield pumping units achieve up to 20% energy savings. This sector holds significant potential for energy efficiency improvements.
Motor engineers must not only study the motors themselves but also analyze the characteristics of the loads they drive. This approach enables the design of rare-earth permanent magnet motor products that offer advanced performance, reliable operation, and reasonable pricing.
V. Advancing Toward Lightweight Design
Aerospace products, electric vehicles, CNC machine tools, computers, audiovisual equipment, medical devices, and portable opto-mechatronic products all impose stringent requirements for compact size and lightweight motors. Permanent magnet synchronous motors have been developed and applied in elevator technology due to their compact size, energy efficiency, excellent controllability, and suitability for low-speed direct drive. This eliminates the need for gear reduction units and enables speed regulation through frequency variation. With advancements in electronic and control technologies, rare earth permanent magnet synchronous motor technology is expected to evolve toward higher energy efficiency, mechatronic integration, enhanced performance, specialized applications, and lightweight designs, becoming increasingly refined.
