Abstract: In some aspects, the techniques described herein relate to a method of manufacturing a shrouded impeller, including: arranging a shell relative to an impeller, wherein the impeller includes a plurality of blades, wherein the shell includes a plurality of slots, and wherein the arranging step includes aligning each of the slots with a tip of a respective one of the blades of the impeller; applying brazing paste to each of the tips by using the slots to direct the brazing paste to the tips; arranging a shroud relative to the impeller; and joining the impeller and shroud using a brazing technique.

Abstract: An electric compressor includes an electric motor including a rotor and stator and a shaft rotating with the rotor to drive a compressor impeller. Bearings support the shaft. A housing encloses the impeller shaft, the bearings and the electric motor, and a sensor for sensing a condition within the housing. A control for the electric motor receives information from the sensor indicative of the potential of migrated refrigerant when the electric motor is not running. The control is operable to actuate a countermeasure to deliver heat into the housing to boil off the migrated refrigerant. A method is also disclosed.

Abstract: A housing for a refrigerant compressor may include a first portion made of a metallic material and surrounding moving parts of the refrigerant compressor. The housing may further include a second portion mounted to the first portion and surrounding non-moving, electronic parts of the refrigerant compressor. The second portion is made of a plastic material.

Abstract: In some aspects, the techniques described herein relate to a method of manufacturing a shrouded impeller, including: arranging a shell relative to an impeller, wherein the impeller includes a plurality of blades, wherein the shell includes a plurality of slots, and wherein the arranging step includes aligning each of the slots with a tip of a respective one of the blades of the impeller; applying brazing paste to each of the tips by using the slots to direct the brazing paste to the tips; arranging a shroud relative to the impeller; and joining the impeller and shroud using a brazing technique.

Abstract: In some aspects, the techniques described herein relate to a refrigerant compressor, including: a stator; a rotor configured to rotate with respect to the stator; and at least one step seal between the rotor and the stator, wherein the step seal includes a first tooth and a second tooth extending from the rotor toward the stator, wherein a downstream surface of the first tooth and an upstream surface of the second tooth are arranged at an angle relative to one another, wherein the angle is less than 90°.

Abstract: This disclosure relates to refrigerant compressors, and, in particular, relates to cooling for the power electronics of such compressors. An example refrigerant system includes a main refrigerant loop in communication with a condenser, an evaporator, and a compressor. The refrigerant system further includes at least one cooling line configured to direct refrigerant from the main refrigerant loop to cool a chamber containing electronic components. A method is also disclosed.

Abstract: A refrigerant compressor includes, among other things, a first stage and a second stage downstream of the first stage, and a cooling line configured to cool power electronics. The cooling line is configured to be switched between a first mode and a second mode. The first mode is configured to dump refrigerant between the first stage and the second stage, and the second mode is configured to dump refrigerant upstream of the first stage.

Abstract: A refrigerant compressor according to an exemplary aspect of the present disclosure includes, among other things, a cooling jacket including a plurality of perforations configured to cause refrigerant flowing through the perforations to form impingement jets and further configured to direct the impingement jets onto a surface adjacent a stator. The refrigerant compressor may be used in a heating, ventilation, and air conditioning (HVAC) chiller system, for example.

Abstract: In some aspects, the techniques described herein relate to a refrigerant compressor, including: a stator; a rotor configured to rotate with respect to the stator; and at least one step seal between the rotor and the stator, wherein the step seal includes a first tooth and a second tooth extending from the rotor toward the stator, wherein a downstream surface of the first tooth and an upstream surface of the second tooth are arranged at an angle relative to one another, wherein the angle is less than 90°.

Abstract: A compressor according to an exemplary aspect of the present disclosure includes, among other things, a rotor configured to rotate with respect to a stator, the stator having an abradable portion. At least one labyrinth seal is between the rotor and the stator, wherein the labyrinth seal comprises a plurality of teeth extending from the rotor toward the abradable portion.

Abstract: A refrigerant compressor includes a magnetic bearing assembly including insulation for the coils and lamination stack of the assembly. The lamination stack includes coil apertures extending axially between opposed axial faces. An insert partially extends into a first coil aperture to prevent direct contact between first and second coils. The insert includes a first leg extending into a slot formed in the lamination stack and a second leg radially spaced-apart from the first leg with the second leg extending axially into the first coil aperture. An annular cover having first and second legs extends into respective slots and apertures of the lamination stack. A second annular cover is provided on the opposite face of the coils that is connected to free ends of the second legs. The lamination stack and coils are coated with an insulative material such as epoxy.

Abstract: In some aspects, the techniques described herein relate to a refrigerant compressor, including: a stator; a rotor configured to rotate with respect to the stator; and at least one step seal between the rotor and the stator, wherein the step seal includes a first tooth and a second tooth extending from the rotor toward the stator, wherein a downstream surface of the first tooth and an upstream surface of the second tooth are arranged at an angle relative to one another, wherein the angle is less than 90°.

Abstract: This disclosure relates to an axial magnetic bearing for a centrifugal refrigerant compressor, and a corresponding system and method. A centrifugal refrigerant compressor system according to an exemplary aspect of the present disclosure includes, among other things, an impeller connected to a shaft, and a magnetic bearing system supporting the shaft. The magnetic bearing system includes an axial magnetic bearing, which itself includes a first permanent magnet configured to generate a first bias flux, a second permanent magnet axially spaced-apart from the first permanent magnet and configured to generate a second bias flux, and an electromagnet. The electromagnet includes a coil arranged radially outward of the first and second permanent magnets, and the electromagnet is configured to selectively generate either a first control flux or a second control flux to apply a force to the shaft in a first axial direction or second axial direction opposite the first axial direction, respectively.

Abstract: This disclosure relates to refrigerant compressors, and, in particular, relates to cooling for the power electronics of such compressors. An example refrigerant system includes a main refrigerant loop in communication with a condenser, an evaporator, and a compressor. The refrigerant system further includes at least one cooling line configured to direct refrigerant from the main refrigerant loop to cool a chamber containing electronic components. A method is also disclosed.

Abstract: This disclosure relates to an axial magnetic bearing for a centrifugal refrigerant compressor, and a corresponding system and method. A centrifugal refrigerant compressor system according to an exemplary aspect of the present disclosure includes, among other things, an impeller connected to a shaft, and a magnetic bearing system supporting the shaft. The magnetic bearing system includes an axial magnetic bearing, which itself includes a first permanent magnet configured to generate a first bias flux, a second permanent magnet axially spaced-apart from the first permanent magnet and configured to generate a second bias flux, and an electromagnet. The electromagnet includes a coil arranged radially outward of the first and second permanent magnets, and the electromagnet is configured to selectively generate either a first control flux or a second control flux to apply a force to the shaft in a first axial direction or second axial direction opposite the first axial direction, respectively.

Abstract: A refrigerant compressor according to an exemplary aspect of the present disclosure includes, among other things, an impeller configured to rotate about an axis, and a shroud. The impeller has a plurality of blades. The shroud is secured to the impeller with an adhesive at tips of the plurality of blades.

Abstract: This disclosure relates to a refrigerant compressor including a magnetic bearing assembly, and more particularly, to insulation for use in connection with the magnetic bearing assembly. In some aspects, the techniques described herein relate to a refrigerant compressor including an electric motor configured to rotationally drive an impeller via a shaft, and a radial magnetic bearing assembly including a lamination stack coated with an epoxy material.

Abstract: A refrigerant compressor according to an exemplary aspect of the present disclosure includes, among other things, a first stage and a second stage downstream of the first stage, and a cooling line configured to cool power electronics. The cooling line is configured to be switched between a first mode and a second mode. The first mode is configured to dump refrigerant between the first stage and the second stage, and the second mode is configured to dump refrigerant upstream of the first stage.

Abstract: In some aspects, the techniques described herein relate to a refrigerant compressor, including: a stator; a rotor configured to rotate with respect to the stator; and at least one step seal between the rotor and the stator, wherein the step seal includes a first tooth and a second tooth extending from the rotor toward the stator, wherein a downstream surface of the first tooth and an upstream surface of the second tooth are arranged at an angle relative to one another, wherein the angle is less than 90°.

Abstract: A compressor according to an exemplary aspect of the present disclosure includes, among other things, a rotor configured to rotate with respect to a stator, the stator having an abradable portion. At least one labyrinth seal is between the rotor and the stator, wherein the labyrinth seal comprises a plurality of teeth extending from the rotor toward the abradable portion.