Cooling of high-power permanent magnet machine rotor
AssigneeHamilton Sundstrand Corporation
InventorsDebabrata Pal, Ashutosh Joshi, Andreas C. Koenig
Life of this patent
Estimating the term…
Abstract
A rotor of an electric machine includes a rotor core, a plurality of permanent magnets located at the rotor core, and a rotor sleeve enclosing the rotor core and the plurality of permanent magnets. One or more sleeve cooling channels are positioned between a radially outer surface of the rotor core and a radially inner surface of the rotor sleeve and extend axially along a length of the rotor. One or more radial cooling channels extend radially outwardly from an interior of the rotor core to the one or more sleeve cooling channels. The one or more radial cooling channels are configured to convey a flow of cooling fluid from the interior of the rotor core to the one or more sleeve cooling channels.
Claims18
An electric machine, comprising:
- a stator including a stator winding;
- and
- a rotor configured to rotate about a machine central axis and electromagnetically interactive with the stator across an air gap between the rotor and the stator, the rotor including:
- a rotor core;
- a plurality of permanent magnets disposed at the rotor core;
- a rotor sleeve enclosing the rotor core and the plurality of permanent magnets;
- one or more sleeve cooling channels disposed between a radially outer surface of the rotor core and a radially inner surface of the rotor sleeve and extending axially along a length of the rotor;
- a first mid-stack plate disposed in the rotor core including one or more first radial cooling channels formed in the first mid-stack plate;
- and
- a second mid-stack plate disposed in the rotor core including one or more second radial cooling channels formed in the second mid-stack plate;
- wherein the one or more first radial cooling channels and the one or more second radial cooling channels extend radially outwardly from an interior of the rotor core to the one or more sleeve cooling channels, the one or more first radial cooling channels and the one or more second radial cooling channels configured to convey a flow of cooling fluid from the interior of the rotor core to the one or more sleeve cooling channels.
A rotor of an electric machine, comprising:
- a rotor core;
- a plurality of permanent magnets disposed at the rotor core;
- a rotor sleeve enclosing the rotor core and the plurality of permanent magnets;
- one or more sleeve cooling channels disposed between a radially outer surface of the rotor core and a radially inner surface of the rotor sleeve and extending axially along a length of the rotor;
- one or more radial cooling channels extending radially outwardly from an interior of the rotor core to the one or more sleeve cooling channels, the one or more radial cooling channels configured to convey a flow of cooling fluid from the interior of the rotor core to the one or more sleeve cooling channels;
- and
- one or more sleeve cooling channel outlets of the one or more sleeve cooling channels defined at an axial end of the rotor assembly, so that the flow of cooling fluid exits the one or more sleeve cooling channel outlet in an axial direction;
- wherein the one or more radial cooling channels is a plurality of radial cooling channels at two different axial locations of the rotor.
A method of cooling a rotor of a permanent magnet electric machine, comprising:
- directing a flow of cooling fluid into an interior of a rotor core of the rotor;
- wherein one or more first radial cooling channels are formed in a first mid-stack plate disposed in the rotor core;
- and
- wherein one or more second radial cooling channels are formed in a second mid-stack plate disposed in the rotor core;
- urging the flow of cooling fluid radially outwardly through the one or more first radial cooling channels and radially outwardly through the one or more second radial cooling channels defined in the rotor core;
- and
- directing the flow of cooling fluid from the one or more first radial cooling channels and from the one or more second radial cooling channels along one or more sleeve cooling channels extending in an axial direction between the rotor core and a rotor sleeve surrounding the rotor core.
Dependencies are inferred from the claim text.