Granted Patent B1

US 12,553,432 · App. 19/075,960 · Granted Feb 17, 2026

Inventors: Thomas Raymond Everson (Louisville, KY); Joseph Wilson Latham (Louisville, KY)

Assignee: Haier US Appliance Solutions, Inc.

F04B49/06F04B35/04F04B2203/0401F04B2203/0402

Abstract

Claims (94)

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

receiving, via a controller of the linear compressor, a d-axis current error signal, a q-axis current error signal, and a DC current error signal;

determining, via the controller, a DC voltage component signal based on the DC current error signal, the DC voltage component signal being limited by a first voltage threshold;

then determining, via the controller, a d-axis voltage component signal based, at least in part, on the q-axis current error signal, the d-axis voltage component signal being limited by a second voltage threshold that is different than the first voltage threshold;

then determining, via the controller, a q-axis voltage component signal based, at least in part, on the d-axis current error signal, the q-axis voltage component signal being limited by a third voltage threshold that is less than the second voltage threshold; and

controlling, via the controller, a motor of the linear compressor using a single-phase vector-like control scheme based, at least in part, on the DC voltage component signal, the d-axis voltage component signal and the q-axis voltage component signal.

2 . The method of claim 1 , wherein:

the first voltage threshold is less than or equal to a maximum peak voltage of a motor drive;

the second voltage threshold is a variable voltage dependent on at least the DC voltage component signal and the maximum peak voltage of a motor drive; and

the third voltage threshold is a variable voltage dependent on the d-axis voltage component signal and the second voltage threshold.

3 . The method of claim 1 , wherein determining, via the controller, the DC voltage component signal based on the DC current error signal further comprises:

applying a first proportional gain to the DC current error signal to obtain a first signal;

applying a first integral gain to the DC current error signal to obtain an output;

integrating the output to obtain a second signal; and

combining the first signal and the second signal to determine the DC voltage component signal.

4 . The method of claim 3 , wherein the second signal is limited based on the first voltage threshold and the first signal.

5 . The method of claim 1 , wherein then determining, via the controller, the q-axis voltage component signal based, at least in part, on the d-axis current error signal further comprises:

applying a second proportional gain to the q-axis current error signal to obtain a third signal;

applying a second integral gain to the d-axis current error signal to obtain a second output;

integrating the second output to obtain a fourth signal; and

combining the third signal and the fourth signal to determine the q-axis voltage component signal.

6 . The method of claim 5 , wherein the fourth signal is limited based on the second voltage threshold and the third signal.

7 . The method of claim 1 , wherein then determining, via the controller, the d-axis voltage component signal based, at least in part, on the q-axis current error signal further comprises:

applying a third proportional gain to the d-axis current error signal to obtain a fifth signal;

applying a third integral gain to the q-axis current error signal to obtain a third output;

integrating the third output to obtain a sixth signal; and

combining the fifth signal and the sixth signal to determine the d-axis voltage component signal.

8 . The method of claim 7 , wherein the sixth signal is limited based on the third voltage threshold and the fifth signal.

9 . 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 control the motor, the controller configured to perform operations for controlling the motor, the operations comprising:

receiving a d-axis current error signal, a q-axis current error signal, and a DC current error signal;

determining a DC voltage component signal based on the DC current error signal, the DC voltage component signal being limited by a first voltage threshold;

then determining a d-axis voltage component signal based, at least in part, on the q-axis current error signal, the d-axis voltage component signal being limited by a second voltage threshold that is different than the first voltage threshold;

then determining a q-axis voltage component signal based, at least in part, on the d-axis current error signal, the q-axis voltage component signal being limited by a third voltage threshold that is less than the second voltage threshold; and

controlling a motor of the linear compressor using a single-phase vector-like control scheme based, at least in part, on the DC voltage component signal, the d-axis voltage component signal and the q-axis voltage component signal.

10 . The linear compressor of claim 9 , wherein:

the first voltage threshold is less than or equal to a maximum peak voltage of a motor drive;

the second voltage threshold is a variable voltage dependent on at least the DC voltage component signal and the maximum peak voltage of a motor drive; and

the third voltage threshold is a variable voltage dependent on the d-axis voltage component signal and the second voltage threshold.

11 . The linear compressor of claim 9 , wherein determining the DC voltage component signal based on the DC current error signal further comprises:

applying a first proportional gain to the DC current error signal to obtain a first signal;

applying a first integral gain to the DC current error signal to obtain an output;

integrating the output to obtain a second signal; and

combining the first signal and the second signal to determine the DC voltage component signal.

12 . The linear compressor of claim 9 , wherein then determining the q-axis voltage component signal based, at least in part, on the d-axis current error signal further comprises:

applying a second proportional gain to the q-axis current error signal to obtain a third signal;

applying a second integral gain to the d-axis current error signal to obtain a second output;

integrating the second output to obtain a fourth signal; and

combining the third signal and the fourth signal to determine the q-axis voltage component signal.

13 . The linear compressor of claim 9 , wherein then determining the d-axis voltage component signal based, at least in part, on the q-axis current error signal further comprises:

applying a third proportional gain to the d-axis current error signal to obtain a fifth signal;

applying a third integral gain to the q-axis current error signal to obtain a third output;

integrating the third output to obtain a sixth signal; and

combining the fifth signal and the sixth signal to determine the d-axis voltage component signal.

14 . The linear compressor of claim 9 , wherein:

the piston is a reciprocating piston; and

the motor is a single-phase linear motor.

15 . An appliance, comprising:

a cabinet defining an internal chamber;

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

receiving a d-axis current error signal, a q-axis current error signal, and a DC current error signal;

determining a DC voltage component signal based on the DC current error signal, the DC voltage component signal being limited by a first voltage threshold;

then determining a d-axis voltage component signal based, at least in part, on the q-axis current error signal, the d-axis voltage component signal being limited by a second voltage threshold that is different than the first voltage threshold;

then determining a q-axis voltage component signal based, at least in part, on the d-axis current error signal, the q-axis voltage component signal being limited by a third voltage threshold that is less than the second voltage threshold; and

controlling a motor of the linear compressor using a single-phase vector-like control scheme based, at least in part, on the DC voltage component signal, the d-axis voltage component signal and the q-axis voltage component signal.

16 . The appliance of claim 15 , wherein:

the first voltage threshold is less than or equal to a maximum peak voltage of a motor drive;

the second voltage threshold is a variable voltage dependent on at least the DC voltage component signal and the maximum peak voltage of a motor drive; and

the third voltage threshold is a variable voltage dependent on the d-axis voltage component signal and the second voltage threshold.

17 . The appliance of claim 15 , wherein determining the DC voltage component signal based on the DC current error signal further comprises:

applying a first proportional gain to the DC current error signal to obtain a first signal;

applying a first integral gain to the DC current error signal to obtain an output;

integrating the output to obtain a second signal; and

combining the first signal and the second signal to determine the DC voltage component signal.

18 . The appliance of claim 15 , wherein then determining the q-axis voltage component signal based, at least in part, on the d-axis current error signal further comprises:

applying a second proportional gain to the q-axis current error signal to obtain a third signal;

applying a second integral gain to the d-axis current error signal to obtain a second output;

integrating the second output to obtain a fourth signal; and

combining the third signal and the fourth signal to determine the q-axis voltage component signal.

19 . The appliance of claim 15 , wherein then determining the d-axis voltage component signal based, at least in part, on the q-axis current error signal further comprises:

applying a third proportional gain to the d-axis current error signal to obtain a fifth signal;

applying a third integral gain to the q-axis current error signal to obtain a third output;

integrating the third output to obtain a sixth signal; and

combining the fifth signal and the sixth signal to determine the d-axis voltage component signal.

20 . The appliance of claim 15 , wherein:

the piston is a reciprocating piston; and

the motor is a single-phase linear motor.

Assignments (1)

References Cited (79)