High-speed magnetic suspension electric main shaft for five-freedom numerically-controlled machine tool

The invention discloses a high-speed magnetic suspension electric main shaft for a five-freedom numerically-controlled machine tool. The electric main shaft comprises a rotating shaft (1) installed on a steel cylinder, a two-freedom magnetic suspension asynchronous motor and two three-freedom alternating and direct current hybrid magnetic bearings, wherein the two-freedom magnetic suspension asynchronous motor is installed on the rotating shaft (1) through a two-freedom magnetic suspension asynchronous motor rotor (18); the two three-freedom alternating and direct current hybrid magnetic bearings are symmetrically installed on the rotating shaft (1) on the two sides of the two-freedom magnetic suspension asynchronous motor through three-freedom alternating and direct current hybrid magnetic bearing rotors (12); and any one of the three-freedom alternating and direct current hybrid magnetic bearings is combined with the two-freedom magnetic suspension asynchronous motor to form a five-freedom magnetic suspension asynchronous motor. The high-speed magnetic suspension electric main shaft has the beneficial effects that no lubrication is required, the axial space is reduced, the structure is symmetrical, the five-freedom magnetic suspension asynchronous motor can be flexibly formed, the non-failure operation time can be greatly improved on the premise of high-speed operation, and the energy loss is reduced.