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.

In an embodiment of the present disclosure, a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes a refrigerant loop and a compressor disposed along the refrigerant loop. The compressor is configured to circulate refrigerant through the refrigerant loop. The HVAC&R system also includes a motor configured to drive the compressor and a variable speed drive (VSD) configured to supply power to the motor. The VSD further includes a first power pod configured to supply a first power to the motor and a second power pod configured to supply a second power to the motor.

A heat pump includes a housing; a liquefier and an evaporator arranged inside the housing; and a compressor interposed between the evaporator and the liquefier in terms of fluid flow, the compressor having a motor, an impeller connected to the motor, and a diffusor, the diffusor having a diffusor portion extending between the motor and the impeller, the diffusor portion having at least two parts, a first part of the diffusor portion being connected to the housing and a second part of the diffusor portion being connected to the motor, wherein the first part of the diffusor portion has an opening, wherein the second part of the diffusor portion is configured to close the opening, and wherein the opening is dimensioned such that the impeller is removable from the housing through the opening.

The present disclosure relates to a 3-phase connector integrated stator and an electric compressor including the same. The 3-phase connector integrated stator includes: a stator including a plurality of teeth formed to extend from a cylindrical core, insulators coupled to the core and the teeth so as to surround outer sides of the core and the teeth, and coils wound on outer sides of the insulators at the respective teeth; a motor cover coupled to an upper insulator in a central axis direction of the stator and having a connector coupling part protruding upwardly from an upper plate; and a 3-phase connector inserted into and coupled to the connector coupling part of the motor cover and having connection pins connected to 3-phase coils of the stator. Therefore, the 3-phase connector may be easily assembled to the stator, and the connector pins may be easily assembled to the 3-phase connector.

A refrigerating cycle device includes a compressor, a motor, and a wiring switch part. The compressor compresses a refrigerant. The motor generates power for compressing the refrigerant by rotating a rotor with voltage applied to a plurality of wirings. The motor is disposed in the compressor. The wiring switch part switches between a plurality of wiring states by changing connection between the plurality of wirings. When a rotational speed of the rotor exceeds a predetermined value, the wiring switch part switches to a first wiring state of the plurality of wiring states. The first wiring state differs from a second wiring state of the plurality of wiring state. Efficiency of the second wiring state is highest at the rotational speed.

A motor drive device includes an inverter output unit that drives a motor using electrical power supplied from a supply power generation unit, a voltage detection unit that detects a voltage value of a DC voltage, a current detection unit, a current limiting resistor and a current change-over switch connected in parallel between a bus and the voltage detection unit, and a motor drive control unit that controls the inverter output unit based on the voltage value and controls turning on and off of the current change-over switch based on the current value. The motor drive control unit turns on the current change-over switch when the motor is to be driven, and turns off the current change-over switch when the current value changes only by an amount less than a first threshold in a first time period during driving of the motor.

A motor drive device includes an inverter output unit that drives a motor using electrical power supplied from a supply power generation unit, a voltage detection unit that detects a voltage value of a DC voltage, a current detection unit, a current limiting resistor and a current change-over switch connected in parallel between a bus and the voltage detection unit, and a motor drive control unit that controls the inverter output unit based on the voltage value and controls turning on and off of the current change-over switch based on the current value. The motor drive control unit turns on the current change-over switch when the motor is to be driven, and turns off the current change-over switch when the current value changes only by an amount less than a first threshold in a first time period during driving of the motor.

A system for controlling a capacity of a compressor includes a motor of the compressor including a main winding connected at a connection point to an auxiliary winding and a drive configured to control a speed of the motor. The system includes a first switch configured to selectively connect the main winding to either a first line voltage or a first output of the drive, a second switch configured to selectively connect the connection point to either a second line voltage or a second output of the drive, and a third switch configured to selectively connect the auxiliary winding to either a capacitor or a third output of the drive. The system includes a solenoid valve configured to selectively either operate in a first capacity or a second capacity. The system includes a control module configured to control the drive, the first switch, the second switch, and the third switch.

A system for controlling a capacity of a compressor includes a motor of the compressor including a main winding connected at a connection point to an auxiliary winding and a drive configured to control a speed of the motor. The system includes a first switch configured to selectively connect the main winding to either a first line voltage or a first output of the drive, a second switch configured to selectively connect the connection point to either a second line voltage or a second output of the drive, and a third switch configured to selectively connect the auxiliary winding to either a capacitor or a third output of the drive. The system includes a solenoid valve configured to selectively either operate in a first capacity or a second capacity. The system includes a control module configured to control the drive, the first switch, the second switch, and the third switch.

A method of operating a heat exchanger system in which a compressor, which is drivable by a motor, is fluidly interposed between an evaporator and a condenser following receipt of a shutdown command is provided. The method includes positioning inlet guide vanes (IGVs) of the compressor in a first position in the event of at least one of a first precondition being in effect and the first and a second precondition both not being in effect. The method further includes positioning the IGVs in a second position in an event the first precondition is not in effect but the second precondition is in effect, ramping a speed of the compressor down until a third precondition takes effect, removing power from the motor and positioning the IGVs in the first position once power is removed from the motor.