The development of rare earth permanent magnet materials and its application in permanent magnet motors
Rare earth permanent magnetic material is a kind of special material with high performance, which is widely used in electronic technology and communication products. From digital cameras, computer hard disk, to automobile, motor and other equipment, rare earth permanent magnetic material can be seen, which provides great help for the development of modern electronic information industry. The application of rare earth permanent magnetic material in motor can make the product performance more stable, lighter weight and lower cost, so it is widely favored by the motor production industry, which provides technical and material support for the development of mechatronics and motor high-tech industry. Through the analysis of rare earth permanent magnet materials, this paper explores the current development status and application in the field of motor, and provides reference for the research and related work of rare earth permanent magnet materials provide advice.
Rare earth permanent magnet materials have experienced a long-term research and exploration process in our country since they came out. At present, they have been widely used in all aspects of people’s life and have played a huge role, the biggest advantage of rare earth permanent magnet material is its light weight, strong performance, stable material and low energy consumption. Rare earth permanent magnet materials have become an important material support for new technologies and new technology products due to their high performance characteristics, especially for motor equipment made of rare earth permanent magnet materials, through the effective combination with electronic technology and microelectronics control technology, the development of electromechanical integration has been realized, and a series of high-tech and high-performance electromechanical integration equipment and products have been manufactured, such as automatic production lines, robots, electronic vehicles, intelligent household appliances, CNC machine tools, medical devices, etc. have brought great convenience and support to the development of China’s high-tech industry, meanwhile, it also assists the economic development and the improvement of people’s living standard [1].
Characteristics and development of rare earth permanent magnet materials
Characteristics of rare earth permanent magnet materials
Rare earth permanent magnet material is an alloy composed of samarium and neodymium mixed rare earth metals and transition metals (such as cobalt, iron, etc.), which is sintered by powder metallurgy, A kind of magnetic material obtained by magnetizing in magnetic field [2]. Rare earth permanent magnet material is a kind of high-performance permanent magnet material. Its magnetism is more than 100 times higher than that of magnetic steel widely used in the 1990 s, compared with the magnetism of iron alloy, it also has great advantages. After magnetizing, rare earth permanent magnet material can have a strong and lasting magnetic field without the help of external energy of enterprises, so it has a wide range of applications and stable performance. The outstanding characteristics of rare earth permanent magnet material are its light weight, small volume, strong magnetism, high stability and low cost. Therefore, it has received extensive attention since it came out. At present, it is as small as digital products, as large as machine tools, automobiles and mechanical equipment, rare earth permanent magnet materials can be seen [3]. The use of rare earth permanent magnet materials improves the high performance and stability of products and reduces the cost of products. Therefore, the rare earth permanent magnet industry has developed rapidly in China and achieved good economic benefits, at present, China’s research and production on rare earth permanent magnet materials and technologies have reached the international leading level.
Development Status of rare earth permanent magnet materials in China
China has very rich rare earth resources, and the output of rare earth ore and rare earth permanent magnet accounts for a large share in the world. The rare earth resources in China are mainly concentrated in inner Mongolia, Shandong, Sichuan and other places, and the rare earth resources are sufficient in reserve, and the rare earth varieties are complete and the quality is high. Therefore, in the development of rare earth materials, research and utilization have very obvious advantages and conditions. Since the discovery of rare earth permanent magnet in 1983, in a short period of more than 30 years, it has achieved rapid development in our country and has made gratifying achievements. At present, the application range of rare earth permanent magnet materials is very wide, it has become a hot project in the national key development and development, and with the continuous investment of technology and capital in this field, the level of scientific research has been continuously improved and the research equipment has been continuously updated, the performance of rare earth permanent magnet materials has been continuously improved, making a very significant contribution to China’s economic development [4]. With the wide application and rapid development of rare earth permanent magnet materials in China, their output and use have become an important index to measure China’s comprehensive national strength and economic development, in the future, China will continue to invest in the development and research of new high-performance Rare earth permanent magnet materials, maximize the industrial advantages, and at the same time, through the effective combination of rare earth permanent magnet materials with other high-tech industries, promote the development of China’s high-tech industry, such as breaking the limitations of traditional industry development, seeking new economic growth points, and providing help for the development of China’s high-tech industry.
Concept and application analysis of rare earth permanent magnet motor
Concept of rare earth permanent magnet motor
Motor is a kind of electric mechanical equipment which uses magnetic field as the communication medium to convert the energy between electric energy and mechanical energy. In general, magnetic field can be generated by electric current or by permanent magnet [5]. The density of general permanent magnets is relative, and their magnetism is limited, so the energy that can be converted is also limited, which can only be used to manufacture some small electrical equipments. However, the use of rare earth permanent magnet material in electric machines can generate a strong magnetic field and can achieve continuous and permanent magnetic field transmission without external force, therefore, rare earth permanent magnet materials can be used to manufacture large motor equipment and precision motor equipment.
At present, rare earth permanent magnet motors have been widely used in China, covering aerospace, national defense equipment, large mechanical and electrical manufacturing, medical equipment, automobiles, production and other fields, its production and manufacturing scope almost covers the entire motor industry.
Characteristics of rare earth permanent magnet motors
Small size and light weight
Compared with other motor equipment, the motor equipment made of rare earth permanent magnet material is smaller and lighter, so it can obviously reduce the overall appearance of the motor equipment and make its application range more extensive, it also brings great convenience to the production, transportation, installation and other links of the motor. For example, a 10Kw ordinary generator normally uses other materials and its motor weight is generally about 200kg, while if rare earth permanent magnetic generator is used, its weight is only about 90kg, it only weighs about half of the former, greatly reducing the area occupied by the motor equipment, improving the service performance of the motor equipment and enhancing the overall service experience of the motor equipment [6].
Strong performance and stability
Strong performance and strong stability the core advantage of rare earth permanent magnet motor equipment, the performance advantage of rare earth permanent magnet motor is incomparable to other traditional motors, at present, China’s research efforts on the performance development and improvement of rare earth permanent magnet motor equipment have been continuously strengthened, the performance of rare earth permanent magnetic motors is developing towards larger and more stable it can be predicted that the performance of rare earth permanent magnetic motors will improve towards more intelligent, scientific and automatic direction in the future, bring greater competitive advantages to the industry. In addition, the speed ratio of rare earth permanent magnet motor is large, and the precision control can also reach an error within 0.1%, which greatly improves the operation stability of CNC machine tool equipment and reduces product quality problems caused by equipment operation errors, improve product quality and production efficiency [7]. Thirdly, the rare earth permanent magnet motor can realize the operation mode of low speed and large torque in the operation process, with large operation control precision and accurate calculation amount, and has small noise and strong stability in the operation process, the advantages such as strong load capacity provide favorable support for the safe operation of equipment and machinery and efficient production.
High efficiency and low energy consumption
The rare earth permanent magnet motor has a high operating efficiency and low energy consumption in its using process, so it has a strong cost performance and economic benefits. Generally speaking, the average power saving rate of rare earth permanent magnet motor in operation can be increased by about 10% compared with ordinary motor, some special rare earth permanent magnet motors can increase the power saving rate by 15% ~ 20% at most, and the production efficiency also has great advantages over traditional motors, at the same time, the rare earth permanent magnet motor can also realize variable speed adjustment through the stepless frequency conversion function, and flexibly adjust variable speed according to the use of different mechanical equipment and use occasions to improve operational efficiency and reduce energy consumption, it has brought great economic benefits to equipment use Enterprises and effectively saved the use cost.
The application of rare earth permanent magnet motors in China
Rare earth permanent magnetic generator
Rare earth permanent magnet generator is the most common application field of rare earth permanent magnet motors. At present, China’s aviation and aerospace fields almost all use rare earth permanent magnet generators to replace traditional generators. At the same time, large ship equipment, rare earth permanent magnetic generators have also been widely used in mechanical equipment, etc. At the same time, small precision generators such as small internal combustion driven generators, vehicle generators, wind turbine generators and so on are also gradually popularizing nationwide.
Permanent magnet synchronous generator
Permanent magnet synchronous generator is also one of the fields in which rare earth permanent magnet motors are widely used at present. Permanent magnet synchronous generator is mainly used in major oil fields, drilling, mining, chemical fiber and glass manufacturing industries in China. Although the permanent magnet synchronous generator is small in size and light in weight, it has more powerful power than the traditional induction generator and has higher power saving rate, so its advantages are very obvious.
Permanent magnet DC motor
Permanent magnet DC motors are mainly used in electrical, electronic equipment, automobiles, small precision instruments and other fields. Because these areas of motor equipment requirements generally have good performance and precise control capabilities, so the permanent magnet DC motor can meet the above requirements and play a good use effect. Among them, the automotive industry is the most important user of permanent magnet direct current motor. The Function of motor to automobile is as much as heart to human body. Therefore, the performance of motor equipment has a great influence on the overall performance of automobile, using permanent magnet direct current motor in the car can effectively reduce the weight of the engine and improve the engine performance, thus promoting the overall safety and stability of the car.
AC servo permanent magnet motor and Brushless DC permanent magnet motor
The invention and application of AC servo permanent magnet engine and Brushless DC permanent magnet engine are mainly to meet the frequency conversion requirements of the motor. This type of motor usually needs to adjust the frequency of the inverter to drive the motor to start, save the cost of electricity and promote the performance improvement [8]. AC servo permanent magnet motor and Brushless DC permanent magnet motor are mainly used in the equipments and fields that require high precision control and high equipment stability, such as robots, CNC machine tools, electric vehicles, intelligent devices, etc, at present, its technology has been continuously optimized and can meet the requirements of multi-field intelligent control.
Future development direction of rare earth permanent magnet motors
Electromechanical integration
The use and optimization of high-performance rare earth permanent magnet motors are the important basis and way to realize electromechanical integration. At present, China’s motor equipment is developing towards a more intelligent, automatic and accurate direction, the R & D and performance optimization of high-performance rare earth permanent magnet motors will play an important role in the development process of electromechanical integration [9]. In the future, servo generators, voice coil motors, synchronous variable frequency motors and other fields will continuously innovate in the use and performance optimization of rare earth permanent magnet motors.
Higher performance and more advanced technology
At present, the optimization and innovation of the technology for rare earth permanent magnet motors in our country have been in a relatively mature stage. With the continuous expansion of the application scope of rare earth permanent magnet motors, the speed and scale of its industry development in our country are also expanding, as a sunrise industry, the continuous improvement of its technology and performance is still the important development direction of the future rare earth permanent magnet motor industry. It will be the important development and application direction of rare earth permanent magnetic motors in the future fields such as mobile power plants, automatic servo motors, permanent magnetic motors, and variable frequency motors with high speed control precision [10].
The development towards miniaturization and intelligentization
At present, when applying rare earth permanent magnet motor equipment in the fields of aerospace products, robots, computer products, audio-visual equipment, intelligent management systems, etc., there are strict requirements for the volume and weight of the equipment, some areas even require the shape of the equipment, so the future RRA will be developed in the direction of lighter, smaller and more diversified, take the development and technical optimization of micro-motor equipment as an important trend in future development and conduct technical research and development in the direction of being more intelligent and precise.
Conclusion
Rare earth permanent magnet materials are widely used in all walks of life with their huge advantages, while the application of rare earth permanent magnet materials in motor equipment improves the overall performance of motor equipment and saves energy consumption, the use efficiency has been improved, thus achieving great development results in the industry. With the continuous progress of science and technology in our country, the future development of the rare earth permanent magnet motor industry will be transformed and upgraded in the direction of technology, intelligence and industry, through technological innovation to promote the development of the industry and promote China’s overall economic development and economic benefits.
Authors: Li Rongjun, gan Jiayi, Xie Meiling, Liang Hongmei, Chen Jianbin (1008-1151(2019)09-0023-03)
Source: China Permanent Magnet Manufacturer – www.rizinia.com
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