NdFeB magnets are currently the most excellent rare earth permanent magnets in terms of comprehensive quality. The use of sintered neodymium iron boron magnets can greatly reduce the amount of magnetic materials used, reduce the size and weight of the motor, and greatly increase the conversion efficiency of electrical energy to mechanical energy. Compared with ordinary permanent magnets, the energy efficiency is increased by more than 10%-15%. The accelerated penetration of neodymium iron boron magnets is conducive to energy saving and carbon emission reduction. In addition to electricity consumption in electric smelting, 80%-90% of domestic electricity is consumed by motors; the implementation of new energy efficiency standards for inverter air conditioners in 2020 will accelerate the penetration of neodymium iron boron magnets in this field. In the future, driven by the domestic peak carbon dioxide emissions and carbon neutrality policies, more industrial fields will increase energy efficiency standards, so that upgrading motor standards will become the most important part of this.
The main magnetic properties of NdFeB magnet directly affects the performance of motor are remanence, coercivity (intrinsic coercivity), maximum magnetic energy product and Curie temperature.
Remanence refers to the maximum magnetic flux intensity that a magnet can provide without an external magnetic field after magnetization. The coercivity indicates the resistance of the magnet to demagnetization. The maximum magnetic energy product means the magnet can provide. The Curie temperature is the temperature point at which the magnetism of the magnet disappears, and it represents the temperature range in which the magnet can work.
In addition, the shape of magnet also has a large impact on the performance of motor, such as the thickness, width, and chamfer will not only affect the efficiency of the magnet, but also affect the accuracy of the magnet during mechanical installation and the vibration in use, and finally affect the efficiency and cost of the motor.