WO2009088517A1 - Use of an adjustable expansion valve to control dehumidification - Google Patents
Use of an adjustable expansion valve to control dehumidification Download PDFInfo
- Publication number
- WO2009088517A1 WO2009088517A1 PCT/US2008/050832 US2008050832W WO2009088517A1 WO 2009088517 A1 WO2009088517 A1 WO 2009088517A1 US 2008050832 W US2008050832 W US 2008050832W WO 2009088517 A1 WO2009088517 A1 WO 2009088517A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- refrigerant
- set forth
- superheat
- control
- refrigerant system
- Prior art date
Links
- 238000007791 dehumidification Methods 0.000 title claims abstract description 17
- 239000003507 refrigerant Substances 0.000 claims abstract description 67
- 230000001143 conditioned effect Effects 0.000 claims abstract description 13
- 238000001816 cooling Methods 0.000 claims description 12
- 238000000034 method Methods 0.000 claims 11
- 238000009530 blood pressure measurement Methods 0.000 claims 4
- 238000009529 body temperature measurement Methods 0.000 claims 4
- 238000005259 measurement Methods 0.000 claims 2
- 238000004378 air conditioning Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
- F24F3/12—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
- F24F3/14—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
- F24F3/1405—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification in which the humidity of the air is exclusively affected by contact with the evaporator of a closed-circuit cooling system or heat pump circuit
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/30—Expansion means; Dispositions thereof
- F25B41/31—Expansion valves
- F25B41/34—Expansion valves with the valve member being actuated by electric means, e.g. by piezoelectric actuators
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/21—Refrigerant outlet evaporator temperature
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/25—Control of valves
- F25B2600/2513—Expansion valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/19—Pressures
- F25B2700/193—Pressures of the compressor
- F25B2700/1931—Discharge pressures
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/21—Temperatures
- F25B2700/2115—Temperatures of a compressor or the drive means therefor
- F25B2700/21152—Temperatures of a compressor or the drive means therefor at the discharge side of the compressor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
Definitions
- This application relates to a refrigerant system incorporating an adjustable expansion valve, and more particularly, to a refrigerant system wherein this adjustable expansion valve is controlled to achieve desired dehumidif ⁇ cation within a climate- controlled environment.
- a typical example of such an adjustable expansion device is an electronic expansion valve.
- Refrigerant systems are known in the HVAC&R (heating, ventilation, air conditioning and refrigeration) art, and operate to compress and circulate a refrigerant throughout a closed-loop refrigerant circuit, connecting a plurality of components, to condition a secondary fluid to be delivered to a climate-controlled space.
- refrigerant is compressed in a compressor from a lower to a higher pressure and delivered to a heat rejection heat exchanger (condenser or gas cooler). From the heat rejection heat exchanger, where heat is typically transferred from the refrigerant to an ambient environment, a high-pressure refrigerant flows to an expansion device where it is expanded to a lower pressure and temperature and then is routed to a heat accepting heat exchanger (evaporator), where refrigerant cools a secondary fluid to be delivered to the conditioned environment. From the evaporator, refrigerant is returned to the compressor.
- evaporator heat accepting heat exchanger
- refrigerant is returned to the compressor.
- refrigerant systems is an air conditioning system, which operates to condition (cool and often dehumidify) air to be delivered into a climate- controlled zone or space.
- Refrigerant systems are utilized to provide temperature control, and often humidity control, for air supplied into an occupied environment.
- One feature that is important to the reliable and efficient operation of a refrigerant system is the amount of superheat of the refrigerant leaving the evaporator and moving to the compressor.
- the superheat which is defined as a difference between the actual temperature and the saturation temperature of the refrigerant, must be kept within a tight band for most efficient and reliable operation of the refrigerant system.
- a refrigerant system operates most efficiently with the lowest safe superheat amount that can be accurately sensed and maintained over a wide range of environmental and operating conditions. For various reasons, the superheat needs to be kept several degrees above zero, and it is typically maintained in the low range from 6 to 12° F.
- Control of the evaporator superheat has been provided for a variety of functions, however, the evaporator superheat has not been controlled to control dehumidification of the air being delivered into an environment to be conditioned.
- a control for an electronic expansion valve achieves a desired refrigerant superheat at the evaporator exit such that the dehumidification provided by the refrigerant system to the air delivered into a conditioned environment can be controlled.
- the "dehumidification" mode of superheat control is only entered if a reduced cooling load provided by the refrigerant system is desired.
- various conditions for reliable operation of the refrigerant system such as discharge temperature and saturation suction temperature being within specified respective ranges, have to be satisfied while entering into the
- Figure 1 is a schematic view of the basic refrigerant system incorporating the present invention.
- FIG. 2 is an example of simplified flowchart of one embodiment of the present invention.
- FIG. 1 shows a refrigerant system 20 incorporating a compressor 22 for compressing a refrigerant and delivering it downstream to a heat rejection heat exchanger 24. From the heat rejection heat exchanger 24, the refrigerant passes through an electronic expansion valve 26, and then to an evaporator 30. As shown, air moving over the evaporator 30 is delivered into an environment to be conditioned 32.
- the environment to be conditioned 32 is provided with a control 43 that allows an occupant to select desired temperature and/or humidity levels to be provided by the air being delivered into the environment.
- a control 28 is shown for the electronic expansion device 26.
- transducers or other sensors 34 and 36 are shown in various locations within the refrigerant system 20. As shown, a transducer 34 is provided downstream of the compressor and may sense the pressure and/or temperature at the discharge of the compressor 22. Similarly, a sensor 36 may sense the pressure and/or temperature downstream of the evaporator 30. The sensors 34 and 36 signals are provided to the control 28. It should be noted that some of these sensors are optional and may not be required for certain system configurations.
- Controls are known which operate to control electronic expansion devices to achieve desired superheat values downstream of the evaporator 30.
- desired performance total capacity and efficiency
- the evaporator superheat to low positive values, typically in the range from 6 to 12°F.
- the inventors have recognized that by increasing superheat under certain circumstances, could lead to increased dehumidification capability of the evaporator 30 and in turn lower humidity of the air being delivered into the conditioned environment 32.
- the present invention utilizes its control of the expansion device 26 to achieve increased dehumidification, at least under certain circumstances. It should be noted that total capacity of the evaporator 30 decreases when superheat is increased, while a simultaneous capacity shift from the sensible component to the latent component is taking place. As a result, a sensible heat ratio (the ratio of the sensible capacity to the total capacity) provided by the evaporator 30 is reduced.
- the sensible heat ratio of the evaporator 30 can be controlled by controlling the electronic expansion valve 26 and consequently adjusting superheat at the exit of the evaporator 30. Therefore, by controlling the electronic expansion valve 26, the total evaporator capacity as well its sensible and latent components can be controlled.
- the desired superheat range may be defined by a lower limit and a higher limit, with the lower limit restricted by a minimum value of the evaporator pressure (or saturation temperature) and the higher limit constrained by a discharge temperature threshold.
- evaporator pressure or saturation temperature
- discharge temperature threshold a minimum value of the evaporator pressure (or saturation temperature)
- abnormally low evaporator pressure may cause the evaporator freeze-up and excessively high discharge temperature may lead to the compressor damage.
- the control 28 may normally operate to achieve a desired optimal superheat in a conventional cooling mode, for instance, to provide maximum performance (capacity and efficiency) for the refrigerant system 20 to cool the air delivered to the conditioned environment 32.
- a reduced sensible cooling load is demanded, such as, for instance, when the ambient temperature is sufficiently low or/and sensible cooling load demands in the conditioned space 32 are not significant, the control 28 enters a "dehumidification" mode of superheat control.
- control 28 may control the expansion device 26, such that superheat is adjusted so that the capacity of the evaporator 30 is shifted from cooling to dehumidification (to lower sensible heat ratios) to reduce humidity of the air being delivered into the zone to be conditioned 32.
- a worker of ordinary skill in the art would recognize how to control the electronic expansion device 26, given the goals of this application as described above, including maintaining the operation of the refrigerant system 20 within safety and reliability limits.
- superheat control may be executed at the compressor suction or compressor discharge.
- the compressor suction it can be executed at the location toward the compressor suction instead of the evaporator exit.
- superheat control can be executed at the compressor discharge, if the relationship between suction superheat and discharge superheat is known. Further, even under circumstances when the desired humidity level cannot be precisely achieved by the evaporator superheat control, it still can be noticeably reduced towards the desired value providing a higher degree of comfort for an occupant of the conditioned space.
- compressors could be used in this invention.
- scroll, screw, rotary, or reciprocating compressors can be employed.
- the refrigerant systems that utilize this invention can be used in many different applications, including, but not limited to, stationary and mobile air conditioning systems as well as heat pump systems.
- the refrigerant system can also employ vapor injection, liquid injection, multiple circuits, as well as compressors connected in parallel in a tandem fashion.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Air Conditioning Control Device (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2008801248736A CN101910762A (en) | 2008-01-11 | 2008-01-11 | Use of an adjustable expansion valve to control dehumidification |
PCT/US2008/050832 WO2009088517A1 (en) | 2008-01-11 | 2008-01-11 | Use of an adjustable expansion valve to control dehumidification |
US12/741,392 US20100242508A1 (en) | 2008-01-11 | 2008-01-11 | Use of an adjustable expansion vavle to control dehumidification |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2008/050832 WO2009088517A1 (en) | 2008-01-11 | 2008-01-11 | Use of an adjustable expansion valve to control dehumidification |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2009088517A1 true WO2009088517A1 (en) | 2009-07-16 |
Family
ID=40853353
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2008/050832 WO2009088517A1 (en) | 2008-01-11 | 2008-01-11 | Use of an adjustable expansion valve to control dehumidification |
Country Status (3)
Country | Link |
---|---|
US (1) | US20100242508A1 (en) |
CN (1) | CN101910762A (en) |
WO (1) | WO2009088517A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2011046803A2 (en) | 2009-10-14 | 2011-04-21 | Carrier Corporation | Dehumidification control in refrigerant vapor compression systems |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103512145B (en) * | 2012-06-19 | 2016-08-31 | 珠海格力电器股份有限公司 | Adjusting method and adjusting device of electronic expansion valve for air conditioning unit |
US10556484B2 (en) * | 2015-10-28 | 2020-02-11 | Ford Global Technologies, Llc | Vehicle climate control valve and operating method |
US10488083B2 (en) * | 2015-12-18 | 2019-11-26 | Friedrich Air Conditioning Co., Ltd. | Variable refrigerant package |
JP6332537B2 (en) * | 2016-09-30 | 2018-05-30 | ダイキン工業株式会社 | Air conditioner |
US10415856B2 (en) * | 2017-04-05 | 2019-09-17 | Lennox Industries Inc. | Method and apparatus for part-load optimized refrigeration system with integrated intertwined row split condenser coil |
US10274213B2 (en) * | 2017-05-01 | 2019-04-30 | Haier Us Appliance Solutions, Inc. | Air conditioning system including a hybrid reheat loop |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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US5615560A (en) * | 1995-04-17 | 1997-04-01 | Sanden Corporation | Automotive air conditioner system |
US5664425A (en) * | 1991-03-08 | 1997-09-09 | Hyde; Robert E. | Process for dehumidifying air in an air-conditioned environment with climate control system |
US6427454B1 (en) * | 2000-02-05 | 2002-08-06 | Michael K. West | Air conditioner and controller for active dehumidification while using ambient air to prevent overcooling |
Family Cites Families (18)
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US2350408A (en) * | 1941-05-28 | 1944-06-06 | Honeywell Regulator Co | Direct expansion air conditioning control system |
US3385349A (en) * | 1966-03-01 | 1968-05-28 | Carrier Corp | Control arrangement for an air conditioning system |
US4523435A (en) * | 1983-12-19 | 1985-06-18 | Carrier Corporation | Method and apparatus for controlling a refrigerant expansion valve in a refrigeration system |
US4787211A (en) * | 1984-07-30 | 1988-11-29 | Copeland Corporation | Refrigeration system |
USRE33775E (en) * | 1984-08-22 | 1991-12-24 | Emerson Electric Co. | Pulse controlled expansion valve for multiple evaporators and method of controlling same |
US4835976A (en) * | 1988-03-14 | 1989-06-06 | Eaton Corporation | Controlling superheat in a refrigeration system |
DE69732206T2 (en) * | 1996-08-22 | 2005-12-22 | Denso Corp., Kariya | Refrigeration system of the vapor compression type |
US5996360A (en) * | 1997-11-27 | 1999-12-07 | Denso Corporation | Refrigerant cycle system |
US6141981A (en) * | 1999-03-26 | 2000-11-07 | Carrier Corporation | Superheat control for optimum capacity under power limitation and using a suction modulation valve |
US6321549B1 (en) * | 2000-04-14 | 2001-11-27 | Carrier Corporation | Electronic expansion valve control system |
JP2002061922A (en) * | 2000-08-14 | 2002-02-28 | Fujitsu General Ltd | Method for contorlling air conditioner |
ITTO20030792A1 (en) * | 2002-10-08 | 2004-04-09 | Danfoss As | VALVE CONTROL DEVICE AND PROCEDURE |
KR100540808B1 (en) * | 2003-10-17 | 2006-01-10 | 엘지전자 주식회사 | Control method for Superheating of heat pump system |
US7096679B2 (en) * | 2003-12-23 | 2006-08-29 | Tecumseh Products Company | Transcritical vapor compression system and method of operating including refrigerant storage tank and non-variable expansion device |
US7290402B1 (en) * | 2003-12-29 | 2007-11-06 | Heatcraft Refrigeration Products Llc | Expansion valve control system and method and refrigeration unit employing the same |
US7234313B2 (en) * | 2004-11-02 | 2007-06-26 | Stargate International, Inc. | HVAC monitor and superheat calculator system |
JP3852015B1 (en) * | 2005-05-30 | 2006-11-29 | ダイキン工業株式会社 | Humidity control device |
EP2488796B1 (en) * | 2009-10-14 | 2018-12-12 | Carrier Corporation | Dehumidification control in refrigerant vapor compression systems |
-
2008
- 2008-01-11 CN CN2008801248736A patent/CN101910762A/en active Pending
- 2008-01-11 WO PCT/US2008/050832 patent/WO2009088517A1/en active Application Filing
- 2008-01-11 US US12/741,392 patent/US20100242508A1/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5664425A (en) * | 1991-03-08 | 1997-09-09 | Hyde; Robert E. | Process for dehumidifying air in an air-conditioned environment with climate control system |
US5615560A (en) * | 1995-04-17 | 1997-04-01 | Sanden Corporation | Automotive air conditioner system |
US6427454B1 (en) * | 2000-02-05 | 2002-08-06 | Michael K. West | Air conditioner and controller for active dehumidification while using ambient air to prevent overcooling |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2011046803A2 (en) | 2009-10-14 | 2011-04-21 | Carrier Corporation | Dehumidification control in refrigerant vapor compression systems |
EP2488796A4 (en) * | 2009-10-14 | 2015-11-25 | Carrier Corp | Dehumidification control in refrigerant vapor compression systems |
Also Published As
Publication number | Publication date |
---|---|
US20100242508A1 (en) | 2010-09-30 |
CN101910762A (en) | 2010-12-08 |
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