Granted Patent B1

US 12,656,038 · App. 19/070,698 · Granted Jun 16, 2026

Inventors: Joseph Wilson Latham (Louisville, KY); Gregory William Hahn (Mt. Washington, KY)

Assignee: Haier US Appliance Solutions, Inc.

F25B49/025F04B49/20H02P21/0089H02P21/26

Abstract

Claims (60)

1 . A method for operating a linear compressor of an appliance, the method comprising:

operating a motor of the linear compressor in order to drive a rotor of the motor;

obtaining, via a controller of the linear compressor, a voltage feedback measurement of the motor;

adjusting, via the controller, a control setpoint for the motor based on the voltage feedback measurement and a voltage threshold; and

controlling, via the controller, the motor of the linear compressor based, at least in part, on the adjusted control setpoint so as to implement a flux weakening operation when the voltage feedback measurement is greater than or equal to the voltage threshold.

2 . The method of claim 1 , wherein the voltage threshold is determined based on a DC bus voltage of a motor drive of the motor.

3 . The method of claim 1 , wherein the motor is controlled using a single-phase phasor based control scheme.

4 . The method of claim 3 , wherein the control setpoint is a target velocity-current phase difference.

5 . The method of claim 1 , wherein the motor is controlled using a single-phase vector based control scheme.

6 . The method of claim 5 , wherein the control setpoint is a target d-axis current component.

7 . The method of claim 1 , wherein adjusting the control setpoint for the motor so as to implement the flux weakening operation based on the voltage feedback measurement and the voltage threshold comprises:

comparing the voltage feedback measurement to the voltage threshold; and

setting the control setpoint to a negative value when the voltage feedback measurement is greater than or equal to the voltage threshold.

8 . A linear compressor defining an axial direction and a vertical direction, the linear compressor for an appliance comprising:

a cylindrical casing defining a compressor chamber;

a piston positioned within the compressor chamber and being movable along the axial direction;

a motor operably coupled to the piston; and

a controller configured to perform operations for controlling the motor, the operations comprising:

operating the motor in order to drive a rotor of the motor;

obtaining a voltage feedback measurement of the motor;

adjusting a control setpoint for the motor so as to implement a flux weakening operation based on the voltage feedback measurement and a voltage threshold; and

controlling the motor based, at least in part, on the adjusted control setpoint when the voltage feedback measurement is greater than or equal to the voltage threshold.

9 . The linear compressor of claim 8 , wherein the voltage threshold is determined based on a DC bus voltage of a motor drive of the motor.

10 . The linear compressor of claim 8 , wherein:

the motor is controlled using a single-phase phasor based control scheme; and

the control setpoint is a target velocity-current phase difference.

11 . The linear compressor of claim 8 , wherein:

the motor is controlled using a single-phase vector based control scheme; and

the control setpoint is a target d-axis current component.

12 . The linear compressor of claim 8 , wherein adjusting the control setpoint for the motor so as to implement the flux weakening operation based on the voltage feedback measurement and the voltage threshold comprises:

comparing the voltage feedback measurement to the voltage threshold; and

setting the control setpoint to a negative value when the voltage feedback measurement is greater than or equal to the voltage threshold.

13 . The linear compressor of claim 8 , wherein:

the piston is a reciprocating piston; and

the motor is a single-phase linear motor.

14 . An appliance, comprising:

a cabinet defining an internal chamber;

a door rotatably mounted to the cabinet to provide selective access to the internal chamber;

a linear compressor, the linear compressor having a piston movable in a negative axial direction toward a compressor chamber and a positive axial direction away from the compressor chamber;

a motor operably coupled to the piston;

an inverter configured to supply a variable frequency waveform to the motor; and

a controller configured to perform operations for controlling the motor, the operations comprising:

operating the motor in order to drive a rotor of the motor;

obtaining a voltage feedback measurement of the motor;

adjusting a control setpoint for the motor so as to implement a flux weakening operation based on the voltage feedback measurement and a voltage threshold; and

controlling the motor based, at least in part, on the adjusted control setpoint when the voltage feedback measurement is greater than or equal to the voltage threshold.

15 . The appliance of claim 14 , wherein the voltage threshold is determined based on a DC bus voltage of the inverter.

16 . The appliance of claim 14 , wherein:

the motor is controlled using a single-phase phasor based control scheme; and

the control setpoint is a target velocity-current phase difference.

17 . The appliance of claim 14 , wherein:

the motor is controlled using a single-phase vector based control scheme; and

the control setpoint is a target d-axis current component.

18 . The appliance of claim 14 , wherein adjusting the control setpoint for the motor so as to implement the flux weakening operation based on the voltage feedback measurement and the voltage threshold comprises:

comparing the voltage feedback measurement to the voltage threshold; and

setting the control setpoint to a negative value when the voltage feedback measurement is greater than or equal to the voltage threshold.

19 . The appliance of claim 14 , wherein:

the piston is a reciprocating piston; and

the motor is a single-phase linear motor.

20 . The appliance of claim 14 , wherein the appliance is a refrigerator appliance.

Assignments (1)

References Cited (77)