High-speed permanent magnet motor and generator with low-loss metal rotor
View Patent ↗An electric machine is provided including a rotor having a plurality of magnets retained on the rotor. The plurality of magnets are retained via a sleeve. The sleeve is retained via a band. The band includes a stacked plurality of washer laminations. Each of the plurality of washer laminations is electrically insulated from an adjacent washer lamination.
1. A machine, comprising:
a rotor comprising a plurality of rare earth permanent magnets retained on said rotor via a cylindrical sleeve that is retained via a band comprising a stacked plurality of non-magnetic washer laminations, each of said non-magnetic washer laminations being electrically insulated from an adjacent non-magnetic washer lamination of the plurality of non-magnetic washer laminations; and
an opposing pair of end caps configured to axially retain said stacked plurality of non-magnetic washer laminations on said rotor, at least one of said opposing pair of end caps defining a threaded hole configured to receive a correspondingly threaded fastener.
2. The machine of claim 1 , wherein:
said threaded fastener is configured to attach a balancing weight, and said balancing weight is configured to facilitate two-plane dynamic balancing of said rotor.
3. The machine of claim 1 , wherein:
said cylindrical sleeve is configured to attenuate temporal variations of a magnetic field in the rotor generated by said plurality of rare earth permanent magnets interacting with slots of a stator of said machine as said rotor rotates.
4. The machine of claim 1 , wherein:
said plurality of rare earth permanent magnets comprise Samarium Cobalt.
5. The machine of claim 1 , wherein:
said plurality of rare earth permanent magnets comprise Neodymium Iron Boron.
6. The machine of claim 1 , wherein:
each non-magnetic washer lamination of said plurality of non-magnetic washer laminations has a yield strength of at least 170 ksi.
7. The machine of claim 1 , wherein:
each non-magnetic washer lamination of said plurality of non-magnetic washer laminations comprises Inconel.
8. The machine of claim 1 , wherein:
each non-magnetic washer lamination of said plurality of non-magnetic washer laminations has a maximum temperature capability of at least 1000 F.
9. The machine of claim 1 , wherein:
said plurality of rare earth permanent magnets are radially polarized.
10. The machine of claim 1 , wherein:
said machine is a radial flux machine.
11. The machine of claim 1 , wherein:
said rotor is configured to rotate at greater than 10,000 revolutions per minute.
12. The machine of claim 1 , wherein:
said rotor is configured to rotate at greater than 100,000 revolutions per minute.
13. The machine of claim 1 , wherein:
said machine is a motor.
14. The machine of claim 1 , wherein:
said machine is a generator.
15. The machine of claim 1 , wherein:
at least one end cap of said opposing pair of end caps includes a non-magnetic material.