CN105004115B - Control method of electronic expansion valve - Google Patents
Control method of electronic expansion valve Download PDFInfo
- Publication number
- CN105004115B CN105004115B CN201510325059.2A CN201510325059A CN105004115B CN 105004115 B CN105004115 B CN 105004115B CN 201510325059 A CN201510325059 A CN 201510325059A CN 105004115 B CN105004115 B CN 105004115B
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- CN
- China
- Prior art keywords
- discharge superheat
- setting
- expansion valve
- aperture
- control condition
- Prior art date
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Links
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000005057 refrigeration Methods 0.000 claims abstract description 15
- 239000003507 refrigerant Substances 0.000 claims abstract description 6
- 238000004781 supercooling Methods 0.000 claims description 14
- 239000007788 liquid Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000007599 discharging Methods 0.000 description 3
- 230000007812 deficiency Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 241000208340 Araliaceae Species 0.000 description 1
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 description 1
- 235000003140 Panax quinquefolius Nutrition 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 235000008434 ginseng Nutrition 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Classifications
-
- 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
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The embodiment of the invention discloses a control method of an electronic expansion valve. The method comprises the following steps: collecting at least two temperature parameters and/or pressure parameters of the refrigerant at key positions in a refrigeration cycle; and if the at least two temperature parameters and the pressure parameters at the key positions meet preset action conditions, executing opening degree adjusting actions of the electronic expansion valve corresponding to the action conditions. The control method of the electronic expansion valve provided by the embodiment of the invention collects the temperature and pressure parameters of a plurality of key positions on the refrigeration cycle, and integrates the temperature and pressure parameters of the plurality of key positions to implement the opening control of the electronic expansion valve, thereby effectively avoiding the control failure problem when the opening control is implemented according to a single parameter.
Description
Technical field
The present embodiments relate to heat pump assembly technical field, more particularly to a kind of control method of electric expansion valve.
Background technology
Throttling arrangement in existing refrigeration system mainly includes heating power expansion valve, throttle pipe and electric expansion valve.Its
In, compared to heating power expansion valve and capillary, for electric expansion valve because it can be controlled by microprocessor, regulation is rapid
It is convenient, flexible movements, it is widely used in refrigeration systems.
The aperture control method of existing electric expansion valve includes：Electronic expansion valve opening is adjusted according to suction superheat
Method, and the method for adjusting according to the compressor air-discharging degree of superheat electronic expansion valve opening.For being evaporated using full-liquid type
Device, its suction superheat it is very low.Easily there is absorbing gas belt liquid according to the control of suction superheat, or electric expansion valve supplies
The phenomenon of liquid deficiency；Controlled according to discharge superheat, discharge superheat and the load of compressor, the operating mode of unit, compressor
Characteristic etc. have relation, can not accurately determine the desired value of discharge superheat, it may appear that feed flow deficiency or feed flow mistake before expansion valve
More phenomenon, so as to control failure conditions occur.
To find out its cause, it is all to rely solely on system to essentially consist in the existing aperture control method applied to electric expansion valve
A parameter perform aperture control, therefore it is unavoidable aperture control occur not accurate enough, control the situation of actual effect.
The content of the invention
In view of this, the embodiment of the present invention proposes a kind of control method of electric expansion valve, to avoid according to single parameter
Controlled during aperture control the situation of actual effect.
The embodiments of the invention provide a kind of control method of electric expansion valve, methods described includes：
Gather at least two temperature parameters and/or pressure parameter of the refrigerant in kind of refrigeration cycle on key position；
If at least two temperature parameters and/or pressure parameter on the key position meet default operation condition, hold
The aperture regulation action of row electric expansion valve corresponding with the operation condition.
The control method of electric expansion valve provided in an embodiment of the present invention, by gathering refrigerant key in kind of refrigeration cycle
At least two temperature parameters and/or pressure parameter on position, and when at least two temperature parameters on the key position
And/or when pressure parameter meets default operation condition, perform the aperture of electric expansion valve corresponding with the operation condition
Regulation acts, and so as to which the multiple parameters based on multiple key positions in kind of refrigeration cycle perform the aperture control of electric expansion valve, has
The aperture that avoids of effect controls situation that is not accurate enough, or even controlling actual effect.
Brief description of the drawings
By reading the detailed description made to non-limiting example made with reference to the following drawings, of the invention is other
Feature, objects and advantages will become more apparent upon：
Fig. 1 is that the structure of the kind of refrigeration cycle of the control method provided in an embodiment of the present invention using the electric expansion valve is shown
It is intended to；
Fig. 2 is the schematic flow sheet of the control method of electric expansion valve provided in an embodiment of the present invention.
Embodiment
The present invention is described in further detail with reference to the accompanying drawings and examples.It is understood that this place is retouched
The specific embodiment stated is only used for explaining the present invention, rather than limitation of the invention.It also should be noted that for the ease of
Describe, part related to the present invention rather than full content are illustrate only in accompanying drawing.
The embodiments of the invention provide a kind of technical scheme of the control method of electric expansion valve.The electric expansion valve
Control method is applied in the kind of refrigeration cycle of refrigeration system.Referring to Fig. 1, the kind of refrigeration cycle includes：Compressor 1, oil eliminator
2, finned heat exchanger 3, blower fan 4, ball valve 5, device for drying and filtering 6, economizer 7, electric expansion valve 8, full-liquid type shell-tube evaporator 9,
Gas-liquid separator 10.In the technical scheme, the control method of the electric expansion valve includes：Refrigerant is gathered in kind of refrigeration cycle
At least two temperature parameters and/or pressure parameter on middle key position；If at least two temperature ginseng on the key position
Number and/or pressure parameter meet default operation condition, and the aperture for performing electric expansion valve corresponding with the operation condition is adjusted
Section acts.
Referring to Fig. 2, the control method of the electric expansion valve includes：
S21, at least two temperature parameters and/or pressure parameter of the collection refrigerant in kind of refrigeration cycle on key position.
In the present embodiment, by several key positions of the kind of refrigeration cycle set temperature sensor and/or
Pressure sensor, gather temperature parameter and/or pressure parameter on the key position.The quantity of the key position is at least
Two.Further, the key position includes：Condensator outlet, compressor air suction mouth and exhaust outlet of compressor.
The temperature parameter includes：Condensator outlet temperature T1, compressor air suction mouth temperature T2, exhaust outlet of compressor temperature
T3, condensator outlet degree of supercooling Δ T1, compressor air suction degree of superheat Δ T2 and compressor air-discharging degree of superheat Δ T3.
The condensator outlet degree of supercooling Δ T1 refers to saturation temperature corresponding to condensing pressure and condensator outlet temperature T1
Between difference.The compressor air suction degree of superheat Δ T2 refers to the compressor air suction mouth temperature T2 and compressor air suction mouth pressure
Difference between saturation temperature corresponding to power.The compressor air-discharging degree of superheat Δ T3 refers to the exhaust outlet of compressor temperature T3
Difference between saturation temperature corresponding with exhaust outlet of compressor pressure.
The pressure parameter includes：Condensator outlet pressure, low pressure and high-pressure.Wherein, the low pressure pressure
Power is exactly compressor air suction mouth pressure, and the high-pressure is exactly exhaust outlet of compressor pressure.
S22, if at least two temperature parameters and/or pressure parameter on the key position meet default action bar
Part, perform the aperture regulation action of electric expansion valve corresponding with the operation condition.
The operation condition includes：Delivery temperature control condition, low voltage control condition, discharge superheat control condition, fortune
Row control condition.Also, the execution priority order of the operation condition is：Delivery temperature control condition, low voltage control condition,
Discharge superheat control condition, operation control condition.
Specifically, the delivery temperature control condition includes：The temperature of the exhaust outlet of compressor is more than 100 in continuous 10 seconds
DEG C, or continuous 10 seconds of the temperature of the exhaust outlet of compressor is not more than 95 DEG C.Opened corresponding to the delivery temperature control condition
Degree regulation action includes：When the temperature of the exhaust outlet of compressor is more than 100 DEG C in continuous 10 seconds, do not allow the electronics
The aperture of expansion valve turns down；And when the temperature of the exhaust outlet of compressor is not more than 95 DEG C in continuous 10 seconds, it is allowed to by institute
The aperture for stating electric expansion valve turns down.
The low voltage control condition includes：Continuous 60 seconds of saturation temperature corresponding to the compressor air suction mouth pressure is more than the
One setting saturation temperature threshold value, or saturation temperature corresponding to the compressor air suction mouth pressure are set for continuous 10 seconds no more than second
Determine saturation temperature threshold value.Aperture regulation action includes corresponding to the low voltage control condition：When the compressor air suction mouth pressure
When continuous 60 seconds of corresponding saturation temperature is more than the first setting saturation temperature threshold value, the aperture of the electric expansion valve is turned down the
The stride of one setting percentage；And it is not more than second within continuous 10 seconds when saturation temperature corresponding to the compressor air suction mouth pressure
When setting saturation temperature threshold value, stop turning down the aperture of the electric expansion valve action of the stride of the first setting percentage.
The value of the second setting saturation temperature threshold value should be less than the value of the described first setting saturation temperature threshold value.
And, it is preferred that the value of the second setting saturation temperature threshold value is lower than the value of the described first setting saturation temperature threshold value
Two degrees Celsius.
The discharge superheat control condition includes：Discharge superheat is not more than discharge superheat threshold value for continuous 60 seconds, or
Discharge superheat section described in person is more than discharge superheat threshold value in continuous 10 seconds.Aperture corresponding to the discharge superheat control condition is adjusted
Section action includes：When the discharge superheat is not more than discharge superheat threshold value in continuous 60 seconds, by the electric expansion valve
Aperture turn down the stride of the second setting percentage；And it is more than discharge superheat threshold value within continuous 10 seconds when the discharge superheat
When, stop turning down the aperture of the electric expansion valve action of the stride of the second setting percentage.
The operation control condition includes：Condensator outlet degree of supercooling is more than the condensator outlet degree of supercooling upper limit threshold of setting
Value, discharge superheat are more than the discharge superheat upper limit threshold of setting, condensator outlet degree of supercooling no more than the condenser set
Outlet subcooling lower threshold or discharge superheat are no more than the discharge superheat lower threshold set.
Aperture regulation action includes corresponding to the operation control condition：When condensator outlet degree of supercooling is more than the cold of setting
When condenser outlet subcooling upper limit threshold, the aperture of the electric expansion valve is opened to the stride of big 3rd setting percentage；When
When discharge superheat is more than the discharge superheat upper limit threshold of setting, the aperture of the electric expansion valve is opened into big 3rd setting
The stride of percentage；When condensator outlet degree of supercooling is no more than the condensator outlet degree of supercooling lower threshold of setting, by institute
The aperture for stating electric expansion valve turns down the stride of the 4th setting percentage；And when exhaust of the discharge superheat no more than setting
When temperature lower threshold, the aperture of the electric expansion valve is turned down to the stride of the 4th setting percentage.
Although word " first ", " second " etc. can be used for describing various parameters herein, these parameters should not be by
The limitation of these words.These words are only used for a parameter to be made a distinction with another parameter.It will also be understood that word " bag
Include " and/or "comprising" it is used in this specification when, represent the presence of the feature, operation, element and/or component, but be not excluded for
Other one or more features, element, component and/or its presence or addition for combining.
The preferred embodiments of the present invention are the foregoing is only, are not intended to limit the invention, for those skilled in the art
For, the present invention can have various changes and change.All any modifications made within spirit and principles of the present invention, it is equal
Replace, improve etc., it should be included in the scope of the protection.
Claims (4)
- A kind of 1. control method of electric expansion valve, it is characterised in that including：Gather at least two temperature parameters and/or pressure parameter of the refrigerant in kind of refrigeration cycle on key position, the key Position includes：Condensator outlet, compressor air suction mouth and exhaust outlet of compressor；If at least two temperature parameters and/or pressure parameter on the key position meet default operation condition, perform with The aperture regulation action of electric expansion valve corresponding to the operation condition, the operation condition include：Delivery temperature control condition, Low voltage control condition, discharge superheat control condition, operation control condition；The low voltage control condition includes：Saturation temperature corresponding to the compressor air suction mouth pressure is set for continuous 60 seconds more than first Determine saturation temperature threshold value, or saturation temperature corresponding to the compressor air suction mouth pressure is satisfied for continuous 10 seconds no more than the second setting And temperature threshold；Aperture regulation action includes corresponding to the low voltage control condition：When saturation temperature corresponding to the compressor air suction mouth pressure When spending continuous 60 seconds more than the first setting saturation temperature threshold value, the aperture of the electric expansion valve is turned down into the first setting percentage Stride；AndWhen saturation temperature corresponding to the compressor air suction mouth pressure sets saturation temperature threshold value in continuous 10 seconds no more than second, Stop turning down the aperture of the electric expansion valve action of the stride of the first setting percentage.
- 2. according to the method for claim 1, it is characterised in that the execution priority of operation condition order is：Exhaust Temperature control condition, low voltage control condition, discharge superheat control condition, operation control condition.
- 3. according to the method for claim 1, it is characterised in that the discharge superheat control condition includes：Discharge superheat Spend continuous 60 seconds and be not more than discharge superheat threshold value, or the discharge superheat section is more than discharge superheat threshold value in continuous 10 seconds；Aperture regulation action includes corresponding to the discharge superheat control condition：When continuous 60 seconds of the discharge superheat less When discharge superheat threshold value, the aperture of the electric expansion valve is turned down to the stride of the second setting percentage；AndWhen the discharge superheat is more than discharge superheat threshold value in continuous 10 seconds, stop the aperture of the electric expansion valve Turn down the action of the stride of the second setting percentage.
- 4. according to the method for claim 1, it is characterised in that the operation control condition includes：Condensator outlet is subcooled Degree more than setting condensator outlet degree of supercooling upper limit threshold, discharge superheat be more than setting discharge superheat upper limit threshold, Condensator outlet degree of supercooling is not more than setting no more than the condensator outlet degree of supercooling lower threshold or discharge superheat of setting Discharge superheat lower threshold；Aperture regulation action includes corresponding to the operation control condition：When condensator outlet degree of supercooling is more than the condenser of setting When outlet subcooling upper limit threshold, the aperture of the electric expansion valve is opened to the stride of big 3rd setting percentage；When discharge superheat is more than the discharge superheat upper limit threshold of setting, the aperture of the electric expansion valve is opened big by the The stride of three setting percentages；When condensator outlet degree of supercooling is no more than the condensator outlet degree of supercooling lower threshold of setting, by the electronic expansion The aperture of valve turns down the stride of the 4th setting percentage；When discharge superheat is no more than the discharge superheat lower threshold of setting, the aperture of the electric expansion valve is turned down The stride of 4th setting percentage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201510325059.2A CN105004115B (en) | 2015-06-12 | 2015-06-12 | Control method of electronic expansion valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510325059.2A CN105004115B (en) | 2015-06-12 | 2015-06-12 | Control method of electronic expansion valve |
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| Publication Number | Publication Date |
|---|---|
| CN105004115A CN105004115A (en) | 2015-10-28 |
| CN105004115B true CN105004115B (en) | 2017-12-29 |
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| CN201510325059.2A Active CN105004115B (en) | 2015-06-12 | 2015-06-12 | Control method of electronic expansion valve |
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| CN106871476B (en) * | 2017-02-17 | 2019-08-16 | 珠海格力电器股份有限公司 | Air source heat pump unit and control method and device of electronic expansion valve thereof |
| CN107289696B (en) * | 2017-06-19 | 2020-11-24 | 青岛海尔空调电子有限公司 | Control method of throttle valve |
| CN107621102B (en) * | 2017-09-14 | 2019-09-24 | 南京天加环境科技有限公司 | A method of electric expansion valve is controlled based on double degrees of superheat |
| CN108387019B (en) * | 2018-01-29 | 2019-09-24 | 珠海格力电器股份有限公司 | Air conditioning system and control method thereof |
| CN109737572A (en) * | 2019-01-16 | 2019-05-10 | 奥克斯空调股份有限公司 | A kind of expansion valve control method and air conditioner |
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| CN111322801B (en) * | 2020-02-27 | 2021-05-11 | 广东志高暖通设备股份有限公司 | Control method and device of electronic expansion valve |
| CN111288696B (en) * | 2020-02-28 | 2020-10-30 | 贝莱特空调有限公司 | Control method of electronic expansion valve of falling film evaporator |
| CN111297178B (en) * | 2020-04-17 | 2022-03-29 | 青岛海尔智慧厨房电器有限公司 | Steam box and control method thereof |
| CN112460859B (en) * | 2020-12-10 | 2022-03-08 | 珠海格力电器股份有限公司 | Water chilling unit and control method thereof |
| CN116025964B (en) * | 2022-12-29 | 2024-05-03 | 珠海格力电器股份有限公司 | Heat pump unit and cooling control method for variable frequency module of heat pump unit |
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| CN105004115A (en) | 2015-10-28 |
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