CN103574991A - Oil return control method for multi-compressor system - Google Patents
Oil return control method for multi-compressor system Download PDFInfo
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- CN103574991A CN103574991A CN201210274598.4A CN201210274598A CN103574991A CN 103574991 A CN103574991 A CN 103574991A CN 201210274598 A CN201210274598 A CN 201210274598A CN 103574991 A CN103574991 A CN 103574991A
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Abstract
The invention provides an oil return control method for a multi-compressor system. An oil reservoir is arranged in the multi-compressor system; a connecting pipe is led out of an oil balancing hole of each compressor, and is connected to the oil inlet of the oil reservoir; an oil outlet pipe connected with the oil outlet of the oil reservoir is connected to the low-pressure side of each compressor. The method comprises the following steps: S1, measuring the exhaust temperature of the exhaust port of each compressor and the fluid temperature in the connecting pipe, and judging the oil level of each compressor according to a difference calculated by subtracting the fluid temperature from the exhaust temperature; S2, if the judgment result of the oil level of each compressor, in the step S1, indicates an oil-rich state, making residual oil in each compressor flow towards the oil reservoir under the action of pressure difference for storing, and if the judgment result indicates an oil-poor state, making oil in the oil reservoir flow towards each compressor via an oil return loop. According to the method, the oil level of each compressor is judged according to the difference calculated by subtracting the fluid temperature from the exhaust temperature, and the oil reservoir is used for storing residual oil when each compressor is in an oil-rich state and filling oil into each compressor when each compressor is in an oil-poor state, so that reliable running of each compressor is ensured.
Description
Technical field
The present invention relates to the multi-compressor system of air-conditioner, in particular to a kind of multi-compressor system oil return control method.
Background technology
VRF Air Conditioning System is because the features such as pipeline is long, drop is large and elbow is many cause oil return difficulty, oil return problem becomes the critical problem of its reliability service, and adopting the multi-compressor system of many rotor compressor parallel runnings complicated due to system running state, oil return problem is more outstanding.
The common method of at present reply oil return problem comprises carries out rational circuit design to system, and efficient oil eliminator, suitable gas-liquid separator and oil return circulation etc. are set.And for multi-compressor system, conventional oil return measure all can not effectively guarantee balanced oil return, under some operating condition, due to oil return not in time or unbalanced, compressor there will be the situation of oil starvation running or rich oil running, all can endanger the safe handling of compressor and the Performance And Reliability of reduction system.
Summary of the invention
The present invention aims to provide a kind of multi-compressor system oil return control method, thereby controls difficulty and then affect the safe handling reduction systematic function of compressor and the problem of reliability to solve multi-compressor system oil return of the prior art.
To achieve these goals, the invention provides a kind of multi-compressor system oil return control method, oil conservator is set in system, by the equal oilhole of compressor, draws the oil-in that tube connector is connected to oil conservator, the flowline of oil conservator is connected to the low-pressure side of compressor; Multi-compressor system oil return control method comprises the following steps:
The delivery temperature of the exhaust outlet of S1, measurement compressor and the fluid temperature (F.T.) in tube connector, the difference that is deducted fluid temperature (F.T.) by delivery temperature judges compressor oil level;
S2, according to the compressor oil level judged result in step S1, if rich oil state in compressor oil more than needed under differential pressure action, flow to oil conservator and be stored, if oil-poor state the oil in oil conservator by oil return loop, flow to compressor.
Further, magnetic valve and capillary are set in tube connector, measure the Postcapillary temperature of fluid process as fluid temperature (F.T.).
Further, the difference that deducts fluid temperature (F.T.) when delivery temperature is less than on 5 ℃ and lasting 10 seconds, is judged as rich oil state.
Further, the difference that deducts fluid temperature (F.T.) when delivery temperature is greater than on 5 ℃ and lasting 10 seconds, is judged as oil starvation state.
Further, temperature-sensitive bag is set on exhaust outlet and tube connector and carries out temperature survey.
Further, before step S1, comprise:
Step S0, a time period of compressor continuous service.
Further, after step S2, comprise:
If step S3 carries out repairing to compressor, in repairing process, continue the difference of judgement fluid temperature (F.T.), if judgment result is that, oil level normally stops repairing.
Further, step S1 and step S2 circulation are carried out.
Apply technical scheme of the present invention, set up an oil conservator, by the difference of compressor exhaust temperature and fluid temperature (F.T.), judge the oil level of compressor, according to judged result, the oil return loop consisting of oil conservator stores unnecessary oil when compressor rich oil state, when the oil-poor state of compressor, compressor is carried out to repairing, thereby guarantee the reliable running of compressor.
Accompanying drawing explanation
The Figure of description that forms the application's a part is used to provide a further understanding of the present invention, and schematic description and description of the present invention is used for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 shows the system schematic of the multi-compressor system that adopts multi-compressor system oil return control method of the present invention;
Fig. 2 shows the flow chart of multi-compressor system oil return control method of the present invention the first embodiment;
Fig. 3 shows the flow chart of multi-compressor system oil return control method of the present invention the second embodiment;
Fig. 4 shows the flow chart of multi-compressor system oil return control method of the present invention the 3rd embodiment; And
Fig. 5 shows the flow chart of multi-compressor system oil return control method of the present invention the 4th embodiment.
The specific embodiment
It should be noted that, in the situation that not conflicting, embodiment and the feature in embodiment in the application can combine mutually.Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.
Summary of the invention of the present invention comprises the following aspects:
One, utilize the hot physical difference of refrigeration oil and cold-producing medium as the foundation of compressor oil level judgement, to control the oil return loop of multi-compressor system centered by oil conservator.
Two, by the equal oilhole of rotor compressor, draw tube connector, after magnetic valve and capillary, be connected to the oil-in of oil conservator, after the capillary of this section of tube connector, arrange temperature-sensitive bag, for detection of the Guan Wen of this place.The hot physical difference of refrigeration oil and cold-producing medium makes it after capillary-compensated, have respectively different temperature drop amplitudes, and the former is less, and the latter is larger.Therefore, by compressor exhaust temperature and stream, the temperature after the fluid throttling of the equal oilhole of compressor is poor, can rationally judge compressor oil level.
Three, by the lateral aperture of oil conservator, draw tube connector, after capillary, be connected to the suction side of compressor.When aforementioned oil level basis for estimation shows compressor rich oil, compressor oil more than needed flows to oil conservator and is stored under differential pressure action.
Four, by the bottom oil return hole of oil conservator, draw tube connector, after magnetic valve and capillary, be connected to the suction side of compressor, form balanced oil return loop.When aforementioned oil level basis for estimation shows compressor oil starvation, the oil in oil conservator carries out timely repairing through oil return loop to the compressor of oil starvation under differential pressure action.
Figure 1 shows that the system schematic of first embodiment of the invention.This figure has shown the balanced oil return loop of a double compressor system with oil conservator, as shown in the figure, the equal oilhole of the first compressor 11 and the second compressor 12 is connected to respectively the upper end inlet tube of oil conservator 80 by the pipeline of magnetic valve (41,42) and capillary (51,52) is installed; Lateral aperture by oil conservator 80 is connected to the suction side of compressor 11 and 12 by the pipeline of capillary 54 is installed; The spill port of oil conservator 80 lower ends is connected to the suction side of compressor 11 and 12 by the pipeline of magnetic valve 43 and capillary 53 is installed, form balanced oil return loop.In addition, the exhaust end of compressor is also communicated with oil eliminator 30 by check valve 21 and 22, and the escape pipe of oil eliminator is connected to the suction side of compressor 11 and 12 by capillary 55.Oil level line in Fig. 1 in compressor shown in broken lines.
The oil equalizing pipe capillary of R410a cold-producing medium and Φ 1.37 * 800mm specification of take is example, works as T
aor T
bbe less than 5 ℃ and lasting more than 10 seconds, judgement compressor is rich oil state; Work as T
aor T
bbe less than 5 ℃ and in 10 seconds, become and be greater than 5 ℃ or be greater than 5 ℃ and became and be less than 5 ℃ in 10 seconds, judgement compressor oil level is normal; Work as T
aor T
bbe greater than 5 ℃ and lasting more than 10 seconds, judgement compressor oil starvation.Temperature and time parameter while adopting the capillary of other cold-producing medium and other specification or other throttle part can be determined by experiment.
The above embodiment is equally applicable to the multiple modularization air-conditioning unit of two above rotor compressor parallel runnings, and principle is identical with method and the present embodiment.
For the different running statuses of double compressor system, several specific embodiment of method for controlling oil return provided by the invention process respectively as follows:
1) the first embodiment flow chart is shown in Fig. 2.
According to refrigeration requirement, two compressors move simultaneously
Open compressor 11 and 12 simultaneously.Operation certain hour t
1after, according to preceding method, open magnetic valve 41 and 42 and detect compressor 11 and 12 oil level states.
When compressor 11 and 12 equal rich oils, the oil more than needed in compressor flows to oil conservator 80 and is stored under differential pressure action.
When compressor 11 or 12 oil starvations, shut electromagnetic valve 42 or 41, opens magnetic valve 43, and the oil in oil conservator 80 is under differential pressure action, and the low-pressure side that flows to compressor 11 or 12 is carried out repairing timely.
As continuous t
2minute compressor 11 detected and 12 equal oil levels are normal, shut electromagnetic valve 43.
2) the second embodiment flow chart is shown in Fig. 3.
When compressor 11 rich oils, the oil more than needed in compressor flows to oil conservator 80 and is stored under differential pressure action.
When compressor 11 oil starvations, open magnetic valve 43, the oil in oil conservator 80 is under differential pressure action, and the low-pressure side that flows to compressor 11 is carried out repairing timely.
As continuous t
2it is normal minute compressor 11 oil levels to be detected, shut electromagnetic valve 43.
3) the 3rd embodiment flow chart is shown in Fig. 4.
Compressor 11 is shut down and compressor 12 operations, according to refrigeration requirement, opens compressor 11 and close compressor 12.
Compressor 11 is shut down and compressor 12 operations, according to cold, requires to open compressor 11 and close compressor 12.Operation certain hour t
1after, according to preceding method, open magnetic valve 41 and detect compressor 11 oil level states.
When compressor 11 rich oils, the oil more than needed in compressor flows to oil conservator 80 and is stored under differential pressure action.
When compressor 11 oil starvations, open magnetic valve 43, the oil in oil conservator 80 is under differential pressure action, and the low-pressure side that flows to compressor 11 is carried out repairing timely.
As continuous t
2it is normal minute compressor 11 oil levels to be detected, shut electromagnetic valve 43.
4) the 4th embodiment flow chart is shown in Fig. 5.
Compressor 11 is shut down and compressor 12 operations, according to refrigeration requirement, opens compressor 11.
Compressor 11 is shut down and compressor 12 operations, according to refrigeration requirement, opens compressor 11.Operation certain hour t
1after, according to preceding method, open magnetic valve 41 and 42 and detect compressor 11 and 12 oil level states.
When compressor 11 and 12 equal rich oils, the oil more than needed in compressor flows to oil conservator 80 and is stored under differential pressure action.
When compressor 11 or 12 oil starvations, shut electromagnetic valve 42 or 41, opens magnetic valve 43, and the oil in oil conservator 80 is under differential pressure action, and the low-pressure side that flows to compressor 11 or 12 is carried out repairing timely.
As continuous t
2minute compressor 11 detected and 12 equal oil levels are normal, shut electromagnetic valve 43.
From above description, can find out, the above embodiments of the present invention have realized following technique effect: the present invention provides a kind of reliable method for controlling oil return for the multi-compressor system with oil conservator, can under the various running statuses of system, to compressor oil level, rationally judge, for the oil storage of Fuel Tanking Unit and balanced oil return running provide effective foundation, improved oil return reliability and the operation stability of system.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (8)
1. a multi-compressor system oil return control method, it is characterized in that, oil conservator (80) is set in compressor assembly, by the equal oilhole of compressor (11,12), draws the oil-in that tube connector is connected to oil conservator, the flowline of described oil conservator is connected to the low-pressure side of compressor; Described multi-compressor system oil return control method comprises the following steps:
S1, the delivery temperature of exhaust outlet of measuring described compressor (11,12) and the fluid temperature (F.T.) in described tube connector, deducted the difference judgement compressor oil level of described fluid temperature (F.T.) by described delivery temperature;
S2, according to the compressor oil level judged result in step S1, if rich oil state in described compressor (11,12) oil more than needed under differential pressure action, flow to described oil conservator (80) and be stored, if oil-poor state the oil in described oil conservator (80) by oil return loop, flow to compressor (11,12).
2. multi-compressor system oil return control method according to claim 1, is characterized in that, magnetic valve and capillary are set in described tube connector, measures the described Postcapillary temperature of fluid process as described fluid temperature (F.T.).
3. multi-compressor system oil return control method according to claim 1, is characterized in that, the difference that deducts described fluid temperature (F.T.) when described delivery temperature is less than on 5 ℃ and lasting 10 seconds, is judged as rich oil state.
4. multi-compressor system oil return control method according to claim 1, is characterized in that, the difference that deducts described fluid temperature (F.T.) when described delivery temperature is greater than on 5 ℃ and lasting 10 seconds, is judged as oil starvation state.
5. multi-compressor system oil return control method according to claim 1, is characterized in that, on described exhaust outlet and described tube connector, temperature-sensitive bag is set and carries out temperature survey.
6. multi-compressor system oil return control method according to claim 1, is characterized in that, before step S1, comprises:
Step S0, described compressor (11, a 12) time period of continuous service.
7. multi-compressor system oil return control method according to claim 1, is characterized in that, after step S2, comprises:
If step S3 carries out repairing to described compressor (11,12), in repairing process, continue the difference of the described fluid temperature (F.T.) of judgement, if judgment result is that, oil level normally stops repairing.
8. multi-compressor system oil return control method according to claim 1, is characterized in that, described step S1 and step S2 circulation are carried out.
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| CN201210274598.4A CN103574991B (en) | 2012-08-02 | 2012-08-02 | Oil return control method for multi-compressor system |
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| CN201210274598.4A CN103574991B (en) | 2012-08-02 | 2012-08-02 | Oil return control method for multi-compressor system |
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| CN103574991B CN103574991B (en) | 2015-12-02 |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104748782A (en) * | 2015-04-09 | 2015-07-01 | 宁波奥克斯电气有限公司 | Judgment method for oil shortage of multi-connected unit |
| CN104949414A (en) * | 2015-07-10 | 2015-09-30 | 珠海格力电器股份有限公司 | Air conditioner as well as detection method and device for compressor oil level of air conditioner |
| CN106338160A (en) * | 2015-07-08 | 2017-01-18 | 三菱电机株式会社 | Air-Conditioning Device |
| CN107218741A (en) * | 2017-05-11 | 2017-09-29 | 青岛海尔空调电子有限公司 | A kind of multiple on-line system method for controlling oil return |
| CN107388664A (en) * | 2017-08-16 | 2017-11-24 | 广东美的暖通设备有限公司 | The control method of oil return valve, control device and air-conditioning system in air-conditioning system |
| CN107514832A (en) * | 2017-09-21 | 2017-12-26 | 无锡职业技术学院 | A kind of low-temperature air-cooling hot screw pump system |
| CN107642921A (en) * | 2016-07-22 | 2018-01-30 | 约克（无锡）空调冷冻设备有限公司 | Oil balancing system and there is its multiscrew compressor parallel refrigeration unit |
| CN109373635A (en) * | 2018-10-29 | 2019-02-22 | 宁波奥克斯电气股份有限公司 | A kind of air conditioner oil returning control method, device and air conditioner |
| CN115143555A (en) * | 2022-06-30 | 2022-10-04 | 青岛海信日立空调系统有限公司 | Air conditioner System |
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| JPH02302561A (en) * | 1989-05-17 | 1990-12-14 | Mitsubishi Electric Corp | Air conditioner |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104748782A (en) * | 2015-04-09 | 2015-07-01 | 宁波奥克斯电气有限公司 | Judgment method for oil shortage of multi-connected unit |
| CN106338160A (en) * | 2015-07-08 | 2017-01-18 | 三菱电机株式会社 | Air-Conditioning Device |
| CN106338160B (en) * | 2015-07-08 | 2018-11-13 | 三菱电机株式会社 | Air-conditioning device |
| CN104949414A (en) * | 2015-07-10 | 2015-09-30 | 珠海格力电器股份有限公司 | Air conditioner as well as detection method and device for compressor oil level of air conditioner |
| CN107642921A (en) * | 2016-07-22 | 2018-01-30 | 约克（无锡）空调冷冻设备有限公司 | Oil balancing system and there is its multiscrew compressor parallel refrigeration unit |
| CN107218741A (en) * | 2017-05-11 | 2017-09-29 | 青岛海尔空调电子有限公司 | A kind of multiple on-line system method for controlling oil return |
| CN107388664A (en) * | 2017-08-16 | 2017-11-24 | 广东美的暖通设备有限公司 | The control method of oil return valve, control device and air-conditioning system in air-conditioning system |
| CN107388664B (en) * | 2017-08-16 | 2019-12-03 | 广东美的暖通设备有限公司 | The control method of oil return valve, control device and air-conditioning system in air-conditioning system |
| CN107514832A (en) * | 2017-09-21 | 2017-12-26 | 无锡职业技术学院 | A kind of low-temperature air-cooling hot screw pump system |
| CN109373635A (en) * | 2018-10-29 | 2019-02-22 | 宁波奥克斯电气股份有限公司 | A kind of air conditioner oil returning control method, device and air conditioner |
| CN109373635B (en) * | 2018-10-29 | 2020-07-31 | 宁波奥克斯电气股份有限公司 | Air conditioner oil return control method and device and air conditioner |
| CN115143555A (en) * | 2022-06-30 | 2022-10-04 | 青岛海信日立空调系统有限公司 | Air conditioner System |
| CN115143555B (en) * | 2022-06-30 | 2023-08-08 | 青岛海信日立空调系统有限公司 | Air conditioning system |
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