Torquer apparatus

• US 8,164,294 B2
• Filed: 03/28/2007
• Issued: 04/24/2012
• Est. Priority Date: 04/05/2006
• Status: Expired due to Fees

• Current Assignee: CSEM Centre Suisse D'Electronique et de Microtechnique SA
• Original Assignee: CSEM Centre Suisse D'Electronique et de Microtechnique SA
• Inventors: Chételat, Olivier
• Primary Examiner(s): COLON SANTANA, EDUARDO
• Application Number:
  US12/296,096
• Publication Number:
  US 20100007303A1
• Time in Patent Office: 1,854 Days
• Field of Search: 318/689, 318/560, 318/568.11, 318/568.21, 318/647, 310/156.01, 310/195, 310/90.5, 310/162, 310/231, 310/261.1, 310/181, 310/179, 74/54, 74/5.R, 74/54.7, 74/57, 744/790.1, 244/165, 244/79, 250/231.12
• US Class Current: 318/689
• CPC Class Codes: B64G 1/28 using inertia or gyro effect
• CPC Class Codes: G01C 19/30 Erection devices, i.e. devices for restoring rotor axis to a desired position for instrument indicating the vertical G01C19/46
• CPC Class Codes: H02K 16/00 Machines with more than one rotor or stator machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029
• CPC Class Codes: H02K 21/12 with stationary armatures and rotating magnets
• CPC Class Codes: H02K 2201/03 Machines characterised by aspects of the air-gap between rotor and stator
• CPC Class Codes: H02K 2201/18 Machines moving with multiple degrees of freedom
• CPC Class Codes: H02K 41/031 of the permanent magnet type
• CPC Class Codes: Y10T 74/1254 by motor torque

Abstract

In general, one aspect of the subject matter described in this specification features a torquer apparatus that includes a rotor with magnetic poles such that, when radially projected on a concentric octahedron, the same symmetrical pattern is obtained on all faces of the octahedron, the polarity of the poles projected on two adjacent faces of the octahedron being opposite. A stator with at least twenty poles magnetized with coils and such that, when radially projected on a concentric icosahedron, the same symmetrical pattern is obtained on all faces of the icosahedron, the stator being-in nominal position-concentric with the rotor. Real-time measurements, or equivalent information, of the position of the rotor with respect to the stator, and real-time measurements, or equivalent information, of exported torque from the stator, or of the orientation of the rotor with respect to the stator can be obtained. A controller for controlling the current in the coils based on the measurements, or the equivalent information, such that the rotor is magnetically held in the nominal position, and that the desired torque is exported.

Claims

1. A torquer apparatus comprising:

a) a rotor with magnetic poles such that, when radially projected on a concentric octahedron, the same symmetrical pattern is obtained on all faces of said octahedron, the polarity of the poles projected on two adjacent faces of said octahedron being opposite;

b) a stator with at least twenty poles magnetized with coils and such that, when radially projected on a concentric icosahedron, the same symmetrical pattern is obtained on all faces of said icosahedron, said stator being in nominal position concentric with said rotor;

c) means for obtaining real-time measurements, or equivalent information, of the position of the rotor with respect to the stator;

d) means for obtaining real-time measurements, or equivalent information, of exported torque from the stator, or of the orientation of the rotor with respect to the stator;

e) a controller for controlling the current in said coils based on said measurements, or said equivalent information, such that the rotor is magnetically held in said nominal position, and that the desired torque is exported.

2. An apparatus according to claim 1 in which the rotor is contained in the stator.

3. An apparatus according to claim 2 in which there is a source or a distribution of sources of magnetic field at each rotor pole.

4. An apparatus according to claim 2 in which each rotor pole is magnetically connected to its neighbours.

5. An apparatus according to claim 4 in which there is a source or a distribution of sources of magnetic field at each connection between neighbour rotor poles.

6. An apparatus according to claim 2 in which each stator pole is magnetically connected to its neighbours.

7. An apparatus according to claim 2 in which information representing the rotor orientation is obtained from the stator coil currents and stator pole fluxes.

8. An apparatus according to claim 2 in which information representing the rotor position is obtained from the stator coil currents and stator pole fluxes.

9. An apparatus according to claim 2 in which the rotor geometric external shape is spherical and made of opaque materials, and in which the rotor position with respect to the stator is measured with optical position sensors.

10. An apparatus according to claim 9 in which the position sensors measure the distance between the rotor and the stator by measuring the shadow made by the rotor.

11. An apparatus according to claim 9 in which the position sensors measure the distance between the stator and the rotor by detecting reflection from the rotor.

12. An apparatus according to claim 9 in which the position sensors are placed orthogonally between pairs of adjacent stator poles.

13. An apparatus according to claim 2 in which the reluctant torque vector is obtained by interpolation from a multi-dimensional look up table addressed with the rotor orientation measurement or equivalent information.

14. An apparatus according to claim 2 in which the matrix allowing the computation of the force coil currents from the force desired by the magnetic bearing controller is totally or partially obtained by interpolation from a multi-dimensional look-up table addressed with the rotor orientation measurement or equivalent information.

15. An apparatus according to claim 2 in which the matrix allowing the computation of the torque coil currents from the desired torque, possibly compensated for by the reluctant torque, is totally or partially obtained by interpolation from a multi-dimensional look-up table addressed with the rotor orientation measurement or equivalent information.

16. An apparatus according to claim 1 in which the stator is contained in the rotor.