Enhanced economy refrigeration control system

Patent metadata

Field	Value
Publication number	US-9766004-B2
Application number	US-201214114245-A
Country	US
Kind code	B2
Filing date	Apr 5, 2012
Priority date	Apr 29, 2011
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A controller for controlling a refrigeration unit, a method, and a refrigeration system are disclosed. In an illustrative embodiment, a controller stores instructions for a first refrigeration setting and a second refrigeration setting, tracks a cumulative average temperature in a refrigeration element, and activates either the first refrigeration setting or the second refrigeration setting. The first refrigeration setting has a lower average power consumption and a higher range of temperature variation than the second refrigeration setting. The controller activates the first refrigeration setting until the cumulative average temperature goes outside a selected temperature range; then the controller activates the second refrigeration setting until the cumulative average temperature is within a target temperature range that has a lower threshold that is greater than the lower threshold of the selected temperature range and an upper threshold that is less than the upper threshold of the selected temperature range.

First claim

We claim:

1. A controller for controlling a refrigeration unit, the controller configured for:
storing instructions for a first refrigeration setting having a first average power consumption and a first range of temperature variation;
storing instructions for a second refrigeration setting having a second average power consumption and a second range of temperature variation, wherein the first average power consumption is lower than the second average power consumption, and the second range of temperature variation is smaller than the first of temperature variation;
tracking a cumulative average temperature in a refrigeration element; and
activating either the first refrigeration setting or the second refrigeration setting, wherein the controller activates the first refrigeration setting while the cumulative average temperature is within a selected temperature range having a lower threshold and an upper threshold, and once the cumulative average temperature is less than the lower threshold or greater than the upper threshold of the selected temperature range, the controller activates the second refrigeration setting until the cumulative average temperature is within a target temperature range that has a second lower threshold that is greater than the lower threshold of the selected temperature range and a second upper threshold that is less than the upper threshold of the selected temperature range.

2. The controller of claim 1 , wherein in the first refrigeration setting, the controller alternately activates a first phase and a second phase in the refrigeration unit, wherein the controller activates the first phase when an upper temperature threshold of the refrigeration element is detected, and the controller activates the second phase when a lower temperature threshold of the refrigeration element is detected.

3. The controller of claim 2 , wherein the refrigeration unit comprises a compressor and a condenser comprising one or more condenser fans, and in the first phase, the one or more condenser fans are activated and the compressor is operated at at least 80% of a nominal full power, and in the second phase, the one or more condenser fans and the compressor are both inactivated.

4. The controller of claim 3 , wherein in the second refrigeration setting, the one or more condenser fans are activated and the compressor is operated at a lower average power than in the first phase of the first refrigeration setting.

5. The controller of claim 2 , wherein the refrigeration unit comprises one or more evaporator fans, the one or more evaporator fans are activated during a majority of each of the first phase and the second phase, and the one or more evaporator fans are inactivated an interval of time prior to the end of each of the first phase and the second phase.

6. The controller of claim 5 , wherein the one or more evaporator fans are operated at a lower power during the second phase than during either the first phase or the second refrigeration setting.

7. The controller of claim 1 , wherein the controller controls the refrigeration unit to operate in the first refrigeration setting and then in the second refrigeration setting for a selected total period of time, and the selected temperature range is defined by a product of a rate at which the second refrigeration setting is capable of bringing the cumulative average temperature in the refrigeration element to the target temperature range, and a connection interval of time, defined as an interval of time required for the second refrigeration setting to bring the cumulative average temperature in the refrigeration element to the target temperature range; and wherein the controller controls the refrigeration unit to operate in the first refrigeration setting for the selected total period of time minus the correction interval of time, and then is operated in the second refrigeration setting for the correction interval of time.

8. The controller of claim 1 , wherein the target temperature range is defined using upper and lower margins around a setpoint temperature.

9. The controller of claim 1 , wherein the controller comprises at least one processor, at least one data storage component configured for communication with said at least one processor, and at least one algorithm stored on the at least one data storage component to be executed by the at least one processor.

10. The controller of claim 9 , wherein the at least one algorithm comprises executable instructions for one or more of the first refrigeration setting, the second refrigeration setting, the cumulative average temperature tracker, and the refrigeration setting controller.

11. The controller of claim 1 , wherein the refrigeration element comprises at least one of: a refrigerated supply line provided from the refrigeration unit; a refrigerated environment that is refrigerated by the refrigeration unit; or an air return line for air returning to the refrigeration unit from a refrigerated environment.

12. A method comprising:
providing a first refrigeration control mode and a second refrigeration control mode for operating a refrigeration unit, wherein an average power consumption in the first refrigeration control mode is lower than an average power consumption in the second refrigeration control mode, and the second refrigeration control mode maintains the refrigeration unit within a smaller range of temperature variation than the first refrigeration control mode;
operating the refrigeration unit in the first refrigeration control mode;
monitoring a cumulative average temperature in the refrigeration element since beginning operating the refrigeration unit in the first refrigeration control mode; and
once the cumulative average temperature in the refrigeration element is outside a selected temperature range, switching to operating the refrigeration unit in the second refrigeration control mode, until the cumulative average temperature in the refrigeration element is within a target temperature range around a setpoint temperature, wherein the target temperature range has a second upper limit that is lower than an upper limit of the selected temperature range, and a second lower limit that is higher than a lower limit of the selected temperature range.

13. The method of claim 12 , wherein in the first refrigeration control mode, the refrigeration unit is alternately activated in a first phase and a second phase, wherein the first phase is activated when an upper temperature threshold is detected in the refrigeration element, and the second phase is activated when a lower temperature threshold is detected in the refrigeration element; wherein in the first phase, one or more condenser fans are activated and a compressor is operated at at least 80% of a nominal full power, and in the second phase, the one or more condenser fans and the compressor are both inactivated; and wherein in the second refrigeration control mode, the one or more condenser fans are activated and the compressor is operated at a lower average power than in the first phase.

14. The method of claim 13 , wherein at least one evaporator fan is activated during a majority of each of the first phase, the second phase, and the second refrigeration control mode, with the at least one evaporator fan operated at a lower power during the second phase than during either the first phase or the second refrigeration control mode, wherein the at least one evaporator fan is inactivated an interval of time prior to the end of each of the first phase, the second phase, and the second refrigeration control mode.

15. The method of claim 12 , wherein the refrigeration unit is

Assignees

• Gan Mason
• Chen Yu H
• Soergel David V
• Carrier Corp

Inventors

• Gan Mason
• Chen Yu H
• Soergel David V

Classifications

• F25D2700/12

  Sensors measuring the inside temperature · CPC title

• F25B2600/112

  of evaporator fans · CPC title

• F25B49/02 Primary

  for compression type machines, plants or systems · CPC title

• F25D29/00 Primary

  Arrangement or mounting of control or safety devices · CPC title

• F25B2600/0251

  with on-off operation · CPC title