Demand potential of energy-efficient products such as permanent magnet motors in China
From the 'Made in China 2025 Plan' just released by the State Council, it can be seen that the purpose of the country's formulation of the plan is that the manufacturing industry is the main body of the real economy, the foundation of a country, the foundation of a rich country, and a tool for rejuvenating the country.
Since the inauguration of industrial civilization in the middle of the 18th century, the history of the rise and fall of world powers and the history of struggle of the Chinese nation have repeatedly proved that without a strong manufacturing industry, there can be no country and nation. Persevering in building an advanced and independent manufacturing industry is the only way for our country to enhance its comprehensive national strength, ensure national security, and build a world power! One of its guiding ideologies is innovation-driven and green development. Innovation is the soul and inexhaustible driving force for the development of the manufacturing industry. Green development is the key to breaking the bottleneck constraints of resources and the environment, and the only way to achieve sustainable development of the manufacturing industry.
In recent years, my country’s industrialization has developed rapidly, and the scale of industrial added value has exceeded 21 trillion yuan, accounting for more than 20% of the world’s total. Among more than 500 major industrial products, the output of more than 220 types ranks among the world’s leaders, but It is still in the stage of how to transform from a big manufacturing country to a strong manufacturing country. Although China's industrial development has made great progress, it must be noted that the resource and environmental costs paid are also very large.
In 2013, the national energy consumption reached 3.75 billion tons of standard coal, accounting for about 22% of the world's total energy consumption, of which industrial energy consumption still accounted for more than 70% of domestic primary energy consumption. According to statistics, industrial emissions account for 72% of carbon emissions. Motors are the end product of industrial energy saving and the largest power-consuming equipment.
According to the European Union's 'Increase the Market Share of High-Efficiency Motors and Drives' research report, industrial motors consume 73% of industrial electricity consumption. Among them, in the EU industrial sector, the proportion of electric power consumed by each electric drive system is: 22% for pumps, 16% for fans, 18% for air compressors, 7% for refrigeration compressors, 2% for conveyors, and 35% for other motors. Fans, pumps and compressors account for 63% of the total power consumption.
Data show that in 2013, my country’s motor holdings amounted to about 2.1 billion kW, and the total power consumption was about 3.5 trillion kWh, accounting for 64% of the total electricity consumption of the whole society. Among them, the total consumption of motors in the industrial sector was 2.6 trillion kWh, accounting for about industrial use. 75% of electricity. For every 1% increase in motor energy efficiency in the industrial sector, annual electricity consumption can be saved by about 26 billion kWh. The overall efficiency of the motor system is increased by 5% to 8%, which can save 130 to 230 billion kWh of electricity annually, which is equivalent to the power generation of 2 to 3 Three Gorges power stations.
Permanent magnet transmission technology is a new technology to improve the overall energy efficiency of the motor system. It includes permanent magnet eddy current flexible transmission energy-saving devices, permanent magnet motors, permanent magnet couplings, permanent magnet couplers, etc., and is an important part of the motor system. It has a positive effect on the overall improvement of the safe operation of the motor system, energy saving and consumption reduction. Energy conservation and emission reduction are the eternal theme of social development. Energy conservation of motors and systems is the main battlefield for industrial energy conservation and emission reduction. Technological innovation and technology leadership are important means to achieve energy conservation and emission reduction and to improve motor energy efficiency.
According to the efficiency curve characteristics of the geared motor, the motor has the highest efficiency and the most economical operation when the load is between 80% and 100%. However, in practical applications, the load rate of most gear reduction motors is often below 60% (my country's gear reduction motor drive system is less efficient, only 30% to 40%). The phenomenon of 'big horse-drawn carts' is very common, and electric energy is wasted. As high as 30%, and long-term low-load operation, it is easy to cause damage to the geared motor.
Permanent magnet transmission technology makes there is no rigid connection between the motor and the load. Through the relative movement of the permanent magnet and the conductor, the energy transmission in the air gap is realized. It solves the centering, starting, shock absorption and speed regulation of the rotating load system. And problems such as overload protection, so that the efficiency of the magnetic drive reaches 99%.
Realize the buffered start of the motor, because the motor does not need to overcome the load inertia, which greatly reduces the peak current, reduces power consumption, saves energy, and reduces equipment wear. From the perspective of energy saving and emission reduction, the use of permanent magnet motors instead of asynchronous AC motors has a small size and an efficiency of 100%. The output speed of the motor reaches 300r/s as the best working condition. At this time, a small back cover is placed on the back of the motor. Xingxing reducer, the output speed can reach several to tens of r/s, meeting the needs of various working conditions, such as power plants, steel plants, cement plants, petrochemical and chemical industries, etc., for motor-driven fans, pumps, The energy-saving transmission solutions proposed by belt conveyors and ball mills have achieved a 40% power saving effect. For example, the ball mill drive system is a typical low-speed and high-torque transmission system. Permanent magnet motors can achieve continuous operation at low speed and large torque. Asynchronous motors and DC motors cannot achieve this. This feature makes permanent magnet motors operate at low speed and large torque. The application of the transmission system is very broad.
The rare earth permanent magnet material of the permanent magnet motor has excellent magnetic properties. After being magnetized, it does not require additional energy to establish a strong permanent magnetic field, which is used to replace the electric excitation field of the traditional motor. Rare earth permanent magnet motors are not only high in efficiency, but also simple in structure, and can be small in size and light in weight. It can not only achieve the high performance (such as ultra-high efficiency, ultra-high speed, ultra-high response speed) unmatched by traditional excitation motors, but also can be made into special motors that can meet specific operating requirements, such as elevator traction motors, automotive special motors, etc.
The same is true for elevator motors. The permanent magnet synchronous traction machine is a gearless traction machine. Compared with the traditional geared traction machine, it has no reduction box, and has compact structure, small size, light weight, low temperature rise, and low energy consumption. , Low noise, maintenance-free, wide speed range and stable operation, etc. Under normal circumstances, it can save energy by about 40% compared with non-permanent magnet geared traction machine, and it is very cost-effective.
China is a big rare earth country. Permanent magnet materials and permanent magnet technology will be widely used in the country’s seven strategic new industries, such as energy-saving and environmental protection industries, new energy, continuous permanent magnet motors for wind generators, and new energy vehicles Many permanent magnet materials are used in high-end manufacturing and information industries. The innovation and development of permanent magnet transmission technology is of great significance for my country to realize 2025 intelligent manufacturing, energy saving and emission reduction in the industrial field, and the market prospect of permanent magnet geared motors is broad.