What is magnetic levitation motor
What is magnetic levitation motor?
Magnetic levitation motor is a kind of special motor which has no contact between stator and mover. According to the force of magnetic field, it can be divided into attraction type and repulsion type; According to the coupling degree of magnetic field, it can be divided into the independent control type of suspension force and driving force and the coupling control type of suspension force and driving force; According to the structure of stator and rotor, it is divided into magnetic suspension rotary motor and magnetic suspension linear motor. It is used in maglev train, maglev bearing and maglev artificial heart blood pump.
What is magnetic levitation technology?
Magnetic levitation technology, which is defined as the use of magnetic force to make the object along an axis or several axis to maintain a certain position of technical measures.
The system of magnetic levitation technology is composed of rotor, sensor, controller and actuator. The actuator includes electromagnet and power amplifier. Assuming that in the reference position, the rotor will deviate from its reference position due to a downward disturbance. At this time, the sensor detects the displacement of the rotor from the reference point. The microprocessor as the controller transforms the detected displacement into a control signal, and then the power amplifier converts the control signal into a control current, which generates a magnetic force in the executive magnet, This drives the rotor back to the original balance position. Therefore, whether the rotor is disturbed downward or upward, the rotor can always be in a stable state of equilibrium.
Because of the absence of mechanical contact, magnetic levitation has the following advantages: first, it has no wear and pollution, and can be used in vacuum and corrosive medium for a long time; Second, no mechanical friction, low power consumption, low noise, high efficiency, no need of lubrication and sealing, which can be used in high-speed engineering to solve the problems of lubrication and energy consumption in high-speed mechanical design.
Development of magnetic levitation
Magnetic levitation technology started relatively early. In 1922, German engineer Herman Kemper proposed the principle of electromagnetic levitation, and applied for the patent of magnetic levitation train in 1934. After 1970, with the continuous strengthening of the economic strength of the world’s industrialized countries, in order to improve the transportation capacity to meet the needs of their economic development, Germany, Japan, the United States, Canada, France, Britain and other developed countries began to plan the development of maglev transportation system.
In 1922, Herman Kemper put forward the principle of electromagnetic levitation, so that in the past 30 or 40 years, many problems of magnetic levitation technology, whether it is vehicle performance or operation control technology, have been solved, and many equipment developed have reached the original technical level. With the development of superconducting technology and the improvement of equipment manufacturing process and system construction level, the application ability of magnetic levitation technology has been improved faster.
Magnetic levitation technology classification
According to the properties of coil conductor, it can be divided into normal conduction type and superconducting type; According to the principle of suspension, it can be divided into electromagnetic suspension system and electric suspension system; In principle, it can be divided into two types: constant permeability magnetic attraction type and superconducting magnetic repulsion type. Our country uses special permanent magnet materials, and does not need any other power support, which is called permanent magnetic levitation.
Application of magnetic levitation technology
Magnetic bearing
Traditional magnetic bearings need 5 to 10 non-contact position sensors to detect the displacement of the rotor. But because of the existence of the sensor, the axial size becomes larger, the dynamic performance of the system is reduced, the cost is high and the reliability is low. At the same time, the high price of sensor also limits its promotion in industry. In recent years, combined with the latest achievements of magnetic bearing and sensorless detection, a new research direction, sensorless magnetic bearing, has been born.
Maglev train
The maglev train can run at a high speed of more than 500 km / h because it does not need to contact the track, and it has many advantages, such as smooth and comfortable operation, easy to realize automatic control, no noise, no harmful exhaust emission and so on.
China’s maglev train has been put into practical use, such as Shanghai Hongqiao Airport maglev line. However, due to the high success rate at present, the ability to realize self financing is weak, which limits its wide application.
Magnetic levitation stage
Magnetic levitation is an ideal way to achieve long stroke and ultra precision motion control accuracy, which can meet the requirements of improving the accuracy of processing and measuring equipment.
Magnetic suspension centrifugal blower
Magnetic suspension centrifugal blower is a kind of fan. It is a new type of fan with high efficiency, energy saving and environmental protection, which is formed by integrating magnetic suspension technology and high-speed motor technology into traditional fans. It is widely used in factories, mines, tunnels and other ventilation; Urban sewage treatment; Wind tunnel wind source and other industrial projects.
Magnetic suspension submersible pump
Magnetic levitation submersible pump is a major breakthrough in the field of submersible pump in the world, which effectively solves various disadvantages of traditional submersible pump, such as low conversion efficiency, high power consumption, limited lift, bearing vulnerability, frequent maintenance and so on. Widely used in industrial and mining enterprises for water supply and drainage, farmland irrigation and plateau, mountain water supply and other fields.
Wind turbine energy storage
As one of the application directions of magnetic levitation technology, the application of magnetic levitation technology in flywheel energy storage motor can greatly improve its energy utilization efficiency, and has its application space in industry and automobile industry.
New energy commercial vehicles
The maintenance cost of commercial vehicle permanent magnet motor is high, and the speed can not be increased. If the magnetic levitation technology can be applied, the speed of commercial vehicle permanent magnet motor can be increased by 2 to 3 times, the weight of motor can be reduced a lot, the efficiency is relatively high, and the maintenance free can be realized. The vehicle power supply is direct current power supply, and the magnetic bearing can be powered directly.
Source: China Permanent Magnet Manufacturer – www.rizinia.com
