System and method of controlling a variable-capacity compressor

• US 10,371,426 B2
• Filed: 03/31/2015
• Issued: 08/06/2019
• Est. Priority Date: 04/01/2014
• Status: Active Grant

• Current Assignee: Copeland Corporation LLC (Emerson Electric Company)
• Original Assignee: Emerson Climate Technologies Incorporated (Emerson Electric Company)
• Inventors: Pham, Hung M., Angle, Shane J., Trudeau, Jr., Edward J., Sowani, Chetan
• Primary Examiner(s): Martin, Elizabeth J
• Application Number:
  US14/674,980
• Publication Number:
  US 20150276291A1
• Time in Patent Office: 1,589 Days
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/58 using Internet communication
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/65 for selecting an operating mode
• CPC Class Codes: F24F 11/83 by controlling the supply of heat-exchange fluids to heat-exchangers
• CPC Class Codes: F24F 11/84 using valves
• CPC Class Codes: F24F 11/85 using variable-flow pumps
• CPC Class Codes: F24F 2110/12 of the outside air
• CPC Class Codes: F25B 13/00 Compression machines, plants or systems, with reversible cycle defrosting cycles F25B47/02
• CPC Class Codes: F25B 2313/007 three pipes connecting the outdoor side to the indoor side with multiple indoor units
• CPC Class Codes: F25B 2700/2104 of an indoor room or compartment
• CPC Class Codes: F25B 2700/2106 of fresh outdoor air
• CPC Class Codes: F25B 49/022 Compressor control arrangements

Abstract

A climate-control system may include a variable-capacity compressor unit and a control module controlling the compressor unit. The compressor unit may be operable in a first capacity mode and in a second capacity mode that is higher than the first capacity mode. The control module may be configured to switch the compressor unit among a shutdown state, the first capacity mode and the second capacity mode based on a demand signal and outdoor-air-temperature data.

Claims

1. A climate-control system including a variable-capacity compressor unit and a control module controlling the compressor unit, the compressor unit operable in a first capacity mode and in a second capacity mode that is higher than the first capacity mode, the control module configured to switch the compressor unit among a shutdown state, the first capacity mode and the second capacity mode based on a single type of demand signal from a thermostat and outdoor-air-temperature data,

wherein the control module switches the compressor unit from the shutdown state to the first capacity mode in response to receipt of the demand signal,

wherein the control module switches the compressor unit from the first capacity mode to the second capacity mode while receiving the same demand signal,

wherein the control module operates the compressor unit in the first capacity mode if a measured temperature value of the outdoor-air-temperature data is less than a predetermined temperature value, and

wherein the control module switches the compressor unit from the first capacity mode to the second capacity mode if the measured temperature value of the outdoor-air-temperature data is greater than the predetermined temperature value and a previous runtime of the compressor unit in the second capacity mode during a previous demand period exceeds a predetermined second-capacity mode threshold.

2. The climate-control system of claim 1, wherein the control module receives the demand signal from a single-stage thermostat disposed within a space to be cooled by the climate-control system.

3. The climate-control system of claim 2, further comprising an indoor heat exchanger receiving working fluid from the compressor unit and a blower forcing air into a convective heat transfer relationship with working fluid in the indoor heat exchanger, the blower including a fixed-speed motor or a variable-speed motor operable at a selectable fixed speed tap.

4. The climate-control system of claim 1, wherein the control module switches the compressor unit from the first capacity mode to the second capacity mode based on whether the previous runtime was greater than five minutes.

5. The climate-control system of claim 1, wherein the control module switches the compressor unit from the first capacity mode to the second capacity mode based on whether the compressor unit has been operating in the first capacity mode for greater than a predetermined time period.

6. A climate-control system including a variable-capacity compressor unit and a control module controlling the compressor unit, the compressor unit operable in a first capacity mode and in a second capacity mode that is higher than the first capacity mode, the control module configured to switch the compressor unit among a shutdown state, the first capacity mode and the second capacity mode based on a single type of demand signal from a thermostat and an outdoor-air-temperature value, wherein:

the control module switches the compressor unit from the shutdown state to the first capacity mode in response to receipt of the demand signal,

the control module switches the compressor unit from the first capacity mode to the second capacity mode while receiving the same demand signal,

if the outdoor-air-temperature value is less than a predetermined outdoor-air-temperature value, the control module switches the compressor unit from the shutdown state to the first capacity mode and operates the compressor unit in the first capacity mode until a sooner of the following two conditions occurs;

a first predetermined first-capacity runtime and the demand signal turns off,

if the outdoor-air-temperature value is greater than a predetermined outdoor-air-temperature value, the control module (a) switches the compressor unit from the shutdown state to the first capacity mode, (b) operates the compressor unit in the first capacity mode for a second predetermined first-capacity runtime that is less than the first predetermined first-capacity runtime, and (c) determines whether a previous runtime in the second capacity mode during a previous demand period exceeds a predetermined second-capacity mode threshold,

if the previous runtime in the second capacity mode during the previous demand period exceeds the predetermined second-capacity mode threshold, the control module switches the compressor unit from the first capacity mode to the second capacity mode after the compressor unit operates in the first capacity mode for the second predetermined first-capacity runtime, and

if the previous runtime in the second capacity mode during the previous demand period does not exceed the predetermined second-capacity mode threshold, the control module continues to operate the compressor unit in the first capacity mode following the second predetermined first-capacity runtime.

7. The climate-control system of claim 6, wherein the control module receives the demand signal from a single-stage thermostat disposed within a space to be cooled by the climate-control system.

8. The climate-control system of claim 7, further comprising an indoor heat exchanger receiving working fluid from the compressor unit and a blower forcing air into a convective heat transfer relationship with working fluid in the indoor heat exchanger, the blower including a fixed-speed motor or a variable-speed motor operable at a selectable fixed speed tap.