CN107965937A - A kind of refrigeration unit and its evacuation halt control method - Google Patents
A kind of refrigeration unit and its evacuation halt control method Download PDFInfo
- Publication number
- CN107965937A CN107965937A CN201711144676.8A CN201711144676A CN107965937A CN 107965937 A CN107965937 A CN 107965937A CN 201711144676 A CN201711144676 A CN 201711144676A CN 107965937 A CN107965937 A CN 107965937A
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- Prior art keywords
- compressor
- low
- refrigeration unit
- solenoid valve
- row
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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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
- F25B1/00—Compression machines, plants or systems with non-reversible cycle
-
- 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
- F25B41/20—Disposition of valves, e.g. of on-off valves or flow control 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
- 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
- F25B49/022—Compressor control arrangements
-
- 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
- F25B2500/00—Problems to be solved
- F25B2500/28—Means for preventing liquid refrigerant entering into the compressor
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The invention discloses a kind of refrigeration unit and its evacuate halt control method.The refrigeration unit includes compressor, condenser, throttle valve and evaporator, supplying valve is equipped between the condenser and throttle valve, the condenser both ends are parallel with a branch, the first solenoid valve, capillary and second solenoid valve are equipped with the branch successively, a branch is drawn between the capillary and the first solenoid valve, the pipeline connection between the outlet of the other end of the branch and the evaporator and the compressor low-pressure side.The control method is by detecting low pressure P of the refrigeration unit in stopping process is evacuatedIt is low, high-pressure PIt is highWith delivery temperature TRow, control the opening and closing of the first and second solenoid valves and the shutdown of compressor.The present invention on the basis of ensureing that refrigeration unit evacuates shutdown effect, makes refrigeration unit maintain operation in the range of operation of compressor all the time by controlling halt condition of the refrigeration unit in stopping process is evacuated.
Description
Technical field
The present invention relates to refrigerating field, more particularly to a kind of refrigeration unit and its evacuation halt control method.
Background technology
Refrigeration unit in order to avoid in start process compressor there is liquid hammer, generally use evacuates the control shut down during shutdown
Scheme, i.e., first close supplying valve, allows compressor operating for a period of time, until the refrigerant almost all of low-pressure side is extracted into by compressor
High-pressure side, turns off compressor, when so starting shooting again, just can effectively avoid compressor flooded starts.Pumping of the prior art
There are problems with for empty halt mode：
1 when evacuate shut down when refrigerant almost all be pumped to high-pressure side, low-pressure side may go out almost without refrigerant when starting shooting again
Existing low pressure rapid drawdown, high-pressure rise sharply, and such case may have the risk of the range of operation beyond compressor, cause to compress
The lost of life of machine and refrigeration unit；
2, which evacuate refrigerant almost all when shutting down, is pumped to high-pressure side, low pressure rapid drawdown, and compressor air suction mouth temperature change
Less, so that suction superheat（The corresponding saturation temperature of suction temperature-low pressure）Rise sharply, cause compressor exhaust temperature rapid
Rise, excessive discharge temperature may cause lubricating oil to be carbonized, influence the service life of compressor and refrigeration unit.
The content of the invention
In view of the above-mentioned problems of the prior art, the present invention proposes a kind of refrigeration unit and its evacuates to shut down controlling party
Method.
The technical solution adopted by the present invention is to design a kind of refrigeration unit, including：Compressor, condenser, throttle valve and steaming
Send out device, supplying valve is equipped between the condenser and throttle valve, wherein, the refrigeration unit further include one respectively with compressor
The first branch that low-pressure side is connected with high-pressure side, the first branch are equipped with the first solenoid valve；With one respectively with condensator outlet
The second branch connected with compressor low-pressure side, the second branch are equipped with throttling arrangement.
The first branch and the second branch arrive compressor after first solenoid valve and the throttling arrangement
Pipeline between low-pressure side can share.
In one embodiment, the throttling arrangement includes second solenoid valve and capillary.
In another embodiment, the throttling arrangement is throttle valve.
The low-pressure side of the compressor and high-pressure side are equipped with pressure sensor, and the high-pressure side of the compressor is additionally provided with temperature
Spend sensor.
The present invention also proposes a kind of evacuation halt control method of refrigeration unit, and the control method is freezed by detecting
Low pressure P of the unit in stopping process is evacuatedIt is low, high-pressure PIt is highWith delivery temperature TRow, detected value and setting value are carried out
Compare, and the shutdown of compressor is controlled according to comparative result.
If continuous t1 time detectings are to PIt is low≤PShut down, then compressor shutdown is controlled；
If continuous t2 time detectings are to PIt is high≥PHeight setting, and PIt is low＞ PShut down, then open the first solenoid valve and unloaded, if during continuous t2
Between detect PIt is high＜ PHeight setting-△PIt is high, then the first solenoid valve is closed, up to continuous t1 time detectings to PIt is low≤PShut downWhen, compressor stops
Machine and the first solenoid valve of closing；
If continuous t3 time detectings are to TRow≥TRow's setting, and PIt is low＞ PShut down, then open throttling arrangement or second solenoid valve carry out hydrojet,
Reduce delivery temperature TRowIf continuous t3 time detectings are to TRow＜ TRow's setting-△TRow, up to continuous t1 time detectings to PIt is low≤PShut downWhen,
Compressor shutdown and closing throttling arrangement or second solenoid valve.
The △ PIt is highWith the △ TRowLower limit can be zero.
Compared with prior art, beneficial effects of the present invention are as follows：
1. ensure that refrigeration unit maintains the range of operation of compressor in evacuation stopping process mesohigh pressure, low pressure all the time
It is interior, make refrigeration unit operation relatively reliable；
2. controlling delivery temperature of the refrigeration unit in stopping process is evacuated, ensure delivery temperature all the time in the comfortable fortune of compressor
In line range, make refrigeration unit operation relatively reliable；
3. ensure refrigeration unit reliability service, it also can guarantee that evacuation effect during compressor emergency shutdown, avoid compressor again
Occurs liquid hammer during startup.
Brief description of the drawings
Fig. 1 is the schematic diagram of refrigeration unit of the present invention；
Fig. 2 is the flow chart of control method of the present invention.
Embodiment
The present invention will be described in detail with reference to the accompanying drawings and examples.
Refrigeration unit in order to avoid in start process compressor there is liquid hammer, generally use evacuates the control shut down during shutdown
Scheme, i.e., first close supplying valve, allows compressor operating for a period of time, until the refrigerant almost all of low-pressure side is extracted into by compressor
High-pressure side, turns off compressor, when so starting shooting again, just can effectively avoid compressor flooded starts.
But run according to refrigeration unit caused by halt mode shuts down possibility is evacuated beyond compressor operating scope（Low pressure
It is too low, high pressure is excessive）, excessive discharge temperature the problem of.Over range operation can cause the service life of compressor and refrigeration unit to contract
It is short, and excessive discharge temperature can cause lubricating oil to be carbonized, and equally influence compressor, the service life of refrigeration unit and operation
Reliability.
Refrigeration unit is effectively ensured both by controlling halt condition of the refrigeration unit in stopping process is evacuated in the present invention
The effect of evacuation can be reached, and the interior operation of the comfort standard that refrigeration unit can be maintained all the time.
As shown in Figure 1, refrigeration unit proposed by the present invention includes：Compressor 1, condenser 2, throttle valve 3 and evaporator 4,
Supplying valve 5 is equipped between condenser and throttle valve.Refrigeration unit further includes one and is connected respectively with compressor low-pressure side and high-pressure side
The first branch, which is equipped with the first solenoid valve 6；It is connected respectively with condensator outlet and compressor low-pressure side with one
The second branch, which is equipped with throttling arrangement.
The throttling arrangement can be second solenoid valve 8 and capillary 7 or a throttle valve.
In the embodiment, the first branch and the second branch arrive compressor low-pressure side after the first solenoid valve and throttling arrangement
Between pipeline share.
As described in Figure 2, evacuation halt control method proposed by the present invention comprises the following steps：
Step 1. refrigeration unit receives halt command, and supplying valve closes, starts to evacuate；
Step 2. detects the low pressure P of refrigeration unitIt is low, high-pressure PIt is highWith delivery temperature TRow；
Step 3. detecting system low pressure PIt is lowIf continuous t1 time detectings are to PIt is low≤PShut down, then it is assumed that low-pressure side coolant quantity will not
Cause to be again started up producing liquid hammer, control compression organ.
Step 4. detecting system high-pressure PIt is highIf continuous t2 time detectings are to PIt is high≥PHeight setting, and PIt is low＞ PShut down, then it is assumed that
It is again started up, there may be liquid hammer, opening the first solenoid valve at this time and being unloaded, reduces high-pressure PIt is highIf the continuous t2 times are examined
Measure PIt is high＜ PHeight setting-△PIt is high, then the first solenoid valve is closed, up to continuous t1 time detectings to PIt is low≤PShut down, then it is assumed that low-pressure side is cold
Matchmaker's amount will not cause to be again started up producing liquid hammer, the shutdown of control compressor and the first solenoid valve of closing.
Step 5. detecting system delivery temperature TRowIf continuous t3 time detectings are to TRow≥TRow's setting, and PIt is low＞ PShut down, then it is assumed that
It is again started up, there may be liquid hammer, opening second solenoid valve 2 at this time and carrying out hydrojet, reduce delivery temperature TRowIf the continuous t3 times
Detect TRow＜ TRow's setting-△TRow, and up to continuous t1 time detectings to PIt is low≤PShut down, then it is assumed that low-pressure side coolant quantity will not cause
It is again started up producing liquid hammer, close compressor is closed and second solenoid valve.
Wherein：
t1—PIt is lowDetection time.
PIt is low- low pressure detected value.
PShut down- the setting value shut down according to low pressure.
t2—PIt is highDetection time.
PIt is high- high-pressure detected value.
PHeight settingHigh-pressure setting value when-the first solenoid valve 6 is opened.PHeight settingIt is to be determined by the range of operation of compressor
, compressor is different, PHeight settingWhat is be also provided with is different.
△PIt is highHigh-pressure control accuracy when-the first solenoid valve 6 is closed.△PIt is highThe purpose of this parameter is to subtract
The action frequency of few first solenoid valve, if PIt is highAll the time in PHeight settingAnnex is hovered, the first solenoid valve will frequent movement, acted
In the service life that can frequently influence the first solenoid valve, △ PIt is highDetermined according to the specifically used requirement of experimental conditions and solenoid valve,
If solenoid valve does not have the requirement of action frequency, △ PIt is high0 can be arranged to, needs to be gone according to experimental conditions if requiring
Determine a suitable value.
t3—TRowDetection time.
TRow- delivery temperature detected value.
TRow's settingOutlet air temperature set value when-second solenoid valve 8 is opened.
△TRow--- delivery temperature control accuracy when the first solenoid valve 6 is closed.△TRowAnd according to experimental conditions and electricity
The specifically used requirement of magnet valve determines, if solenoid valve does not have the requirement of action frequency, △ PIt is high0 can be arranged to, if
With regard to needing to be gone to determine a suitable value according to experimental conditions.
The present invention is stopped by controlling halt condition of the refrigeration unit in stopping process is evacuated ensureing that refrigeration unit evacuates
Machine effect（Avoid starting band liquid）On the basis of, refrigeration unit is maintained operation in the range of operation of compressor all the time（Low pressure
Will not too low, high pressure will not be excessive）, and control delivery temperature all the time in the comfortable range of operation in compressor, for one kind more
Control mode is shut down for reliable evacuate.
Above-described embodiment is merely to illustrate the embodiment of the present invention.It should be pointed out that for the general of this area
For logical technical staff, without departing from the inventive concept of the premise, some deformations and change can also be made, these deformations and
Change should all belong to protection scope of the present invention.
Claims (8)
1. a kind of refrigeration unit, including：Compressor, condenser, throttle valve and evaporator, set between the condenser and throttle valve
There is supplying valve, it is characterised in that the first branch being connected respectively with compressor low-pressure side and high-pressure side is further included, this first
Road is equipped with the first solenoid valve；With a second branch being connected respectively with condensator outlet and compressor low-pressure side, this second
Road is equipped with throttling arrangement.
2. refrigeration unit as claimed in claim 1, it is characterised in that the first branch and the second branch are described
Shared after one solenoid valve and the throttling arrangement to the pipeline between compressor low-pressure side.
3. refrigeration unit as claimed in claim 1, it is characterised in that the throttling arrangement includes second solenoid valve and capillary
Pipe.
4. refrigeration unit as claimed in claim 1, it is characterised in that the throttling arrangement is throttle valve.
5. refrigeration unit as claimed in claim 1, it is characterised in that the low-pressure side of the compressor and high-pressure side are equipped with pressure
Force snesor, the high-pressure side of the compressor are additionally provided with temperature sensor.
A kind of 6. evacuation halt control method of any one of the claim 1-5 refrigeration unit, it is characterised in that the control
Method processed is by detecting low pressure P of the refrigeration unit in stopping process is evacuatedIt is low, high-pressure PIt is highWith delivery temperature TRow, will
Detected value compared with setting value, and according to comparative result control compressor shutdown.
7. control method as claimed in claim 6, it is characterised in that
If continuous t1 time detectings are to PIt is low≤PShut down, then compressor shutdown is controlled；
If continuous t2 time detectings are to PIt is high≥PHeight setting, and PIt is low＞ PShut down, then open the first solenoid valve and unloaded, if during continuous t2
Between detect PIt is high＜ PHeight setting-△PIt is high, then the first solenoid valve is closed, up to continuous t1 time detectings to PIt is low≤PShut downWhen, compressor stops
Machine and the first solenoid valve of closing；
If continuous t3 time detectings are to TRow≥TRow's setting, and PIt is low＞ PShut down, then open throttling arrangement or second solenoid valve carry out hydrojet,
Reduce delivery temperature TRowIf continuous t3 time detectings are to TRow＜ TRow's setting-△TRow, up to continuous t1 time detectings to PIt is low≤PShut downWhen,
Compressor shutdown and closing throttling arrangement or second solenoid valve.
8. control method as claimed in claim 7, it is characterised in that the △ PIt is highWith the △ TRowLower limit be zero.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711144676.8A CN107965937B (en) | 2017-11-17 | 2017-11-17 | A kind of refrigeration unit and its evacuate halt control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711144676.8A CN107965937B (en) | 2017-11-17 | 2017-11-17 | A kind of refrigeration unit and its evacuate halt control method |
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| Publication Number | Publication Date |
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| CN107965937A true CN107965937A (en) | 2018-04-27 |
| CN107965937B CN107965937B (en) | 2019-07-16 |
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| CN201711144676.8A Active CN107965937B (en) | 2017-11-17 | 2017-11-17 | A kind of refrigeration unit and its evacuate halt control method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108955006A (en) * | 2018-09-03 | 2018-12-07 | 珠海格力电器股份有限公司 | A kind of refrigeration unit evacuates the control method and refrigeration unit of shutdown |
| CN111854205A (en) * | 2019-04-28 | 2020-10-30 | 青岛海尔智能技术研发有限公司 | Refrigerator equipment, refrigerating system and control method of refrigerating system |
| CN113639415A (en) * | 2021-07-23 | 2021-11-12 | 青岛海尔空调电子有限公司 | Method and device for defrosting air conditioner and air conditioner |
| CN114364929A (en) * | 2019-09-09 | 2022-04-15 | 三菱电机株式会社 | Outdoor unit and refrigeration cycle device |
| CN114459178A (en) * | 2022-03-29 | 2022-05-10 | 重庆美的通用制冷设备有限公司 | Heat exchange unit and air conditioning equipment |
| CN115167559A (en) * | 2022-06-23 | 2022-10-11 | 北京京仪自动化装备技术股份有限公司 | Control method and control system of temperature control system and temperature control system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108955006A (en) * | 2018-09-03 | 2018-12-07 | 珠海格力电器股份有限公司 | A kind of refrigeration unit evacuates the control method and refrigeration unit of shutdown |
| CN111854205A (en) * | 2019-04-28 | 2020-10-30 | 青岛海尔智能技术研发有限公司 | Refrigerator equipment, refrigerating system and control method of refrigerating system |
| CN114364929A (en) * | 2019-09-09 | 2022-04-15 | 三菱电机株式会社 | Outdoor unit and refrigeration cycle device |
| CN114364929B (en) * | 2019-09-09 | 2024-01-02 | 三菱电机株式会社 | Outdoor unit and refrigeration cycle device |
| CN113639415A (en) * | 2021-07-23 | 2021-11-12 | 青岛海尔空调电子有限公司 | Method and device for defrosting air conditioner and air conditioner |
| CN114459178A (en) * | 2022-03-29 | 2022-05-10 | 重庆美的通用制冷设备有限公司 | Heat exchange unit and air conditioning equipment |
| CN114459178B (en) * | 2022-03-29 | 2023-08-29 | 重庆美的通用制冷设备有限公司 | Heat exchange unit and air conditioning equipment |
| CN115167559A (en) * | 2022-06-23 | 2022-10-11 | 北京京仪自动化装备技术股份有限公司 | Control method and control system of temperature control system and temperature control system |
| CN115167559B (en) * | 2022-06-23 | 2023-11-17 | 北京京仪自动化装备技术股份有限公司 | Control method and control system of temperature control system and temperature control system |
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| CN107965937B (en) | 2019-07-16 |
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