Electric centrifugal compressor for vehicles

Abstract

An electric centrifugal compressor for a heat ventilation air conditioning system for vehicles comprises a motor portion ( 20 ) and a centrifugal compressor portion ( 10 ) driven by the motor portion ( 20 ) through a shaft ( 15 ). It comprises an electromagnetic device for levitating the shaft ( 15 ) during functional operation of the electric compressor and auxiliary landing bearings ( 8 ). The electromagnetic device may comprise in particular an axial bearingless motor.

1 . An electric compressor for a heat ventilation air conditioning system for vehicles, the electric compressor comprising:
 a motor portion, and   a centrifugal compressor portion driven by the motor portion through a shaft, auxiliary landing bearings, and   electromagnetic means for levitating the shaft during functional operation of the electric compressor.   
     
     
         2 . The electric compressor according to  claim 1 , wherein the motor portion further comprises an axial bearingless motor and radial electromagnetic means for levitating the shaft. 
     
     
         3 . The electric compressor according to  claim 2 , wherein the radial electromagnetic means further comprises first and second active radial magnetic bearings. 
     
     
         4 . The electric compressor according to  claim 2 , wherein the radial electromagnetic means further comprises first and second radial bearingless motors. 
     
     
         5 . The electric compressor according to  claim 2 , wherein separators are provided between the axial bearingless motor and the radial electromagnetic means for levitating the iron shaft. 
     
     
         6 . The electric compressor according to  claim 2 , wherein the axial bearingless motor further comprises a rotor portion having a plurality of pole pairs armatures and first and second stator portions each having a core with slots respectively for receiving windings configured to impress a motor torque and an axial bearing force, and wherein
 the first and second stator portions are located on each side of the rotor portion.   
     
     
         7 . The electric compressor according to  claim 6 , wherein separate windings are provided in the slots of the first and second stator portions for respectively impressing a motor torque and an axial bearing force. 
     
     
         8 . The electric compressor according to  claim 6 , wherein common windings are provided in the slots of the first and second stator portions for impressing a motor torque and an axial bearing force. 
     
     
         9 . The electric compressor according to  claim 2 , wherein the axial bearingless motor further comprises a rotor portion chosen among an induction rotor, a permanent magnet rotor, a hysteresis rotor and a reluctance rotor. 
     
     
         10 . The electric compressor according to  claim 2 , wherein the centrifugal compressor portion further comprises a wheel disposed at a first end of the shaft, and wherein
 control circuits associated with the axial bearingless motor and the radial electromagnetic means are located at a second end of the shaft and are connected to the axial bearingless motor and the radial electromagnetic means via a feedthrough.   
     
     
         11 . The electric compressor according to  claim 9 , wherein the centrifugal compressor portion further comprises tandem wheels. 
     
     
         12 . The electric compressor according to  claim 9 , wherein the centrifugal compressor portion further comprises double tandem wheels. 
     
     
         13 . The electric compressor according to  claim 10 , wherein the centrifugal compressor portion further comprises double wheels. 
     
     
         14 . The electric compressor according to  claim 1 , wherein the motor portion further comprises an electric motor and the electromagnetic means for levitating the shaft provide an active axial magnetic bearing, and first and second active radial magnetic bearings located on each side of the electric motor. 
     
     
         15 . The electric compressor according to  claim 14 , wherein the centrifugal compressor portion further comprises at least a wheel at a first end of the shaft, wherein the active axial magnetic bearing is located in the vicinity of the centrifugal compressor portion, and wherein
 control circuits associated with the electric motor, the active axial magnetic bearing and the first and second active radial magnetic bearings are located at a second end of the shaft and are connected to the electric motor, the active axial magnetic bearing and the first and second active radial magnetic bearings via a feedthrough.