The magnet and impeller of the brushless DC magnetic drive pump are injected into one to form the rotor of the motor. There is a directly injection molded shaft sleeve in the middle of the rotor, which is fixed in the casing through high-performance ceramic shafts. The stator and circuit board of the motor are sealed in the pump body using epoxy resin adhesive. There is a thin wall isolation between the stator and rotor, which does not require traditional mechanical shaft seals, making it completely sealed. The torque of the motor is generated by the electrification of the coil on the silicon steel sheet (stator), which generates a magnetic field to drive the permanent magnet (rotor) to operate. Perform n (n is an even number) level magnetization on the magnet to form a fully coupled magnetic system between the magnet parts. When the magnetic poles generated by the stator coil are opposite to the magnetic poles of the magnet, that is, the displacement angle between the two magnetic poles Φ= At this point, the magnetic energy of the magnetic system is the lowest; When the magnetic poles rotate to the same pole relative to each other, that is, the displacement angle between the two magnetic poles Φ= At 2 π/n, the magnetic energy of the magnetic system is at its maximum. After removing the external force, due to the mutual repulsion of the magnetic poles of the magnetic system, the magnetic force will restore the magnet to its lowest state of magnetic energy. So the magnet generates motion, driving the magnetic rotor to rotate.