Permanent magnet synchronous motor is the use of permanent magnetic materials to generate excitation magnetic field, instead of electric excitation. It does not require excitation current, no excitation loss in the rotor. Permanent magnet synchronous motor permanent magnet excitation field generated by the current in the stator windings and electromagnetic coupling, so that the motor rotation. The magnetic properties and physical properties of permanent magnet materials are closely related to the performance of permanent magnet synchronous motor. Research and production of permanent magnetic materials developed rapidly.
There are two types of permanent magnet synchronous motor: inner rotor and outer rotor. The inner rotor is suitable for heavy load and high speed applications. The outer rotor is small in size and suitable for elevator without machine room.
Permanent magnet synchronous toothless traction machine with the traditional worm gear, worm-driven traction machine compared with the following advantages:
a) permanent magnet synchronous gearless traction machine is a direct drive, there is no worm gear, worm drive system, permanent magnet synchronous motor is not required for induction motor stator coil place, and the main material for the production of permanent magnet synchronous motor is high energy Density of the high residual magnetic induction and high coercivity of NdFeB, the air gap flux density generally reach more than 0.75T, so you can do small size and light weight.
b) high transmission efficiency. Due to the use of permanent magnet synchronous motor direct drive (no worm gear pair) its transmission efficiency can be increased by 20% to 30%.
c) Permanent magnet synchronous toothless traction machine As there is no noise generated by the bearings in an asynchronous motor running at high speed and the noise generated when the worm gear contacts and drives, the noise of the whole machine can be reduced by 5 ~ 10db (A) .
d) Low energy consumption. From the principle of permanent magnet synchronous motor shows that the excitation is achieved by the permanent magnet, the stator does not require additional excitation current, so the motor power factor can reach very high (theoretically up to 1). At the same time, no current flows through the rotor of the PMSM. There is no problem of rotor loss. Generally lower than the asynchronous motor 45% to 60% wear and tear. Because there is no low efficiency, high energy consumption worm gear transmission, energy consumption to further reduce.
e) permanent magnet synchronous toothless traction machine because there is no problem of tooth wear and do not need regular replacement of lubricating oil, so its long life, and basically no maintenance.
Energy saving and safety are the characteristics of a new generation of permanent magnet synchronous traction elevator and a great technological advance unmatched by traditional elevators. The synthesis and sintering technology of permanent magnetic materials Our country is in the leading level in the world, and the production level of permanent magnet motor in our country also catch up with the world level quickly, which provides favorable conditions for elevator production.
Article from NdFeB Industry Network