CN102094817A - Infinitely variable control compressor for water chiller and loading control method for infinitely variable control compressor - Google Patents
Infinitely variable control compressor for water chiller and loading control method for infinitely variable control compressor Download PDFInfo
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- CN102094817A CN102094817A CN2011100385636A CN201110038563A CN102094817A CN 102094817 A CN102094817 A CN 102094817A CN 2011100385636 A CN2011100385636 A CN 2011100385636A CN 201110038563 A CN201110038563 A CN 201110038563A CN 102094817 A CN102094817 A CN 102094817A
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 41
- 238000000034 method Methods 0.000 title claims abstract description 14
- 239000000446 fuel Substances 0.000 claims description 48
- 235000006506 Brasenia schreberi Nutrition 0.000 claims description 3
- 238000004134 energy conservation Methods 0.000 abstract description 4
- 230000008014 freezing Effects 0.000 abstract 2
- 238000007710 freezing Methods 0.000 abstract 2
- 230000002349 favourable effect Effects 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 description 8
- 238000005057 refrigeration Methods 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 3
- JEIPFZHSYJVQDO-UHFFFAOYSA-N ferric oxide Chemical compound O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 3
- 239000006200 vaporizer Substances 0.000 description 3
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Abstract
The invention discloses an infinitely variable control compressor for a water chiller and a loading control method for the infinitely variable control compressor. A screw rod type water chiller is ensured to realize capacity infinite control according to the actual loading, which is favorable for energy conservation for the water chiller. The compressor comprises a low-pressure chamber, an oil chamber, an oil filter and an oil-way system, wherein the oil-way system consists of an oil supply pipe and a bypass pipe; the oil supply pipe is provided with an oil control valve; and one end of the oil supply pipe is communicated with the oil filter, and the other end of the oil supply pipe is communicated with the oil chamber. The loading control method is mainly characterized in that the compressor loading is controlled accurately through impulse signals according to the relationship of the target effluent temperature of freezing water, the compensation temperature and the actual effluent temperature of freezing water so as to achieve the purpose of energy conservation; and by utilizing the loading control method, compared with the level-four capacity control water chiller of the prior art, the infinitely variable control compressor has the advantage that energy can be saved by more than 5%.
Description
Technical field
The present invention relates to a kind of at the step-less adjustment compressor of screw-type water chiller application and the load controlled method of this compressor.
Background technique
Screw-type water chiller is the nucleus equipment of DESIGN TREND OF MODERN INDUSTRIAL ARCHITECTURE refrigeration air-conditioner, and this handpiece Water Chilling Units should comprise four parts at least: screw compressor, shell and tube condenser, shell and tube evaporator and throttling arrangement.Wherein, the temperature of the cooling water in the handpiece Water Chilling Units be by with condenser in refrigeration agent carry out exchange heat and change, the temperature of chilled water be by with vaporizer in refrigeration agent carry out heat exchange and change, after the refrigeration agent in chilled water and the vaporizer carried out exchange heat, the temperature of the chilled water that flows out from vaporizer was the chilled water water-exit temperature.
Traditional screw compressor comprises low-pressure cavity, oil pocket, and guiding valve and oil-way system, oil-way system is made up of 4 pipelines, is respectively transport pipe, 25% load adjutage, 50% load adjutage, 75% load adjutage.Transport pipe is provided with capillary tube, and an end of transport pipe is communicated with oil strainer, and the other end is communicated with oil pocket; 25% load adjutage, one end links to each other with transport pipe, and the other end is communicated with low-pressure cavity, and 25% load adjutage is provided with control valve; One end of 50% load adjutage is communicated with oil pocket, and the other end is communicated with low-pressure cavity, and 50% load adjutage is provided with control valve; One end of 75% load adjutage is communicated with oil pocket, and the other end is communicated with low-pressure cavity, and 75% load adjutage is provided with control valve.Said structure, by opening the control valve on the different loads adjutage, can order about guiding valve moves, moving of guiding valve can be regulated the load of compressor, and the adjusting by compressor loads can realize the handpiece Water Chilling Units capacity regulating, and this handpiece Water Chilling Units can realize that 4 level capacities regulate according to the variation of actual load, though can save the part energy, but IPLV is lower for its combination property coefficient, and temperature control precision is low, and energy waste still is bigger than normal.
Summary of the invention
The technical problem that the present invention solves provides a kind of step-less adjustment compressor that is used for handpiece Water Chilling Units that makes screw-type water chiller realize stepless capacity regulating according to actual load.
The technical solution adopted for the present invention to solve the technical problems is: the step-less adjustment compressor that is used for handpiece Water Chilling Units, comprise low-pressure cavity, oil pocket, oil strainer and oil-way system, described oil-way system is made up of fuel supply line and bypass tube, the control fuel tap is installed on the described fuel supply line, and an end of fuel supply line is communicated with oil strainer, and the other end is communicated with oil pocket; On the described bypass tube bypass valve is installed, an end of bypass tube is communicated with oil pocket, and the other end is communicated with low-pressure cavity.
Further be: on the described fuel supply line capillary tube is installed.
Further be: described control fuel tap and bypass valve all are solenoid valve.
The present invention also provides a kind of load controlled method that makes screw-type water chiller realize the step-less adjustment compressor that is used for handpiece Water Chilling Units of stepless capacity regulating according to actual load.
Load controlled method of the present invention, comprise the above-mentioned step-less adjustment compressor that is used for handpiece Water Chilling Units, according to chilled water target water-exit temperature T, the actual water-exit temperature T0 of compensation temperature Δ t and chilled water is specially by the switching of pulse signal adjustment control fuel tap and bypass valve:
As T0 〉=T+ Δ t, close bypass valve, open the control fuel tap, make compressor loads;
As T-Δ t＞T0＞T+ Δ t, close bypass valve and control fuel tap, make compressor be positioned at load and keep the stage;
As T0≤T-Δ t, open bypass valve, close the control fuel tap, make compressor unloading;
Wherein, Δ t is 0.1～1 ℃.
Further be: the pulse width of described pulse signal is 0.5～1 second, is spaced apart 0.5～1 second.
The invention has the beneficial effects as follows: can accurately control moving of guiding valve by the switching of control fuel tap and the switching of bypass valve, the load that can make compressor that moves of guiding valve is adjusted arbitrarily between fully loaded zero, and then can make screw-type water chiller carry out stepless capacity regulating according to actual load.
Description of drawings
Fig. 1 is the schematic representation of 4 grades of screw compressors in the prior art;
Fig. 2 is the schematic representation that is used for the step-less adjustment compressor of handpiece Water Chilling Units of the present invention.
Be labeled as among the figure: 1-capillary tube, 3-25% load adjutage, 6-low-pressure cavity, 7-transport pipe, 8-50% load adjutage, 9-75% load adjutage, 10-oil strainer, 11-screw rod, 12-guiding valve, 13-oil pocket, the 14-bypass tube, the 15-fuel supply line, 16-is controlled fuel tap, 17-bypass valve.
Embodiment
The present invention is further described below in conjunction with embodiment.
As shown in Figure 1, in the prior art, the oil-way system of screw compressor is by transport pipe 7,25% load adjutage, 3,50% load adjutages 8 and 75% load adjutage 9 are formed, and transport pipe 7 is provided with capillary tube 1, one end of transport pipe 7 is communicated with oil strainer 10, and the other end is communicated with oil pocket 13; 25% load adjutage, 3 one ends link to each other with transport pipe 7, and the other end is communicated with low-pressure cavity 6, and 25% load adjutage 3 is provided with control valve; One end of 50% load adjutage 8 is communicated with oil pocket 13, and the other end is communicated with low-pressure cavity 6, and 50% load adjutage 8 is provided with control valve; One end of 75% load adjutage 9 is communicated with oil pocket 13, and the other end is communicated with low-pressure cavity 6, and 75% load adjutage 9 is provided with control valve.Use screw compressor of the prior art can only make screw-type water chiller realize the adjusting of 4 level capacities.
As shown in Figure 2, the step-less adjustment compressor that is used for handpiece Water Chilling Units of the present invention, comprise low-pressure cavity 6, oil pocket 13, oil strainer 10 and oil-way system, described oil-way system is made up of fuel supply line 15 and bypass tube 14, and control fuel tap 16 is installed on the described fuel supply line 15, one end of fuel supply line 15 is communicated with oil strainer 10, and the other end is communicated with oil pocket 13; On the described bypass tube 14 bypass valve 17 is installed, an end of bypass tube 14 is communicated with oil pocket 13, and the other end is communicated with low-pressure cavity 6.
During use,, can close bypass valve 17, open control fuel tap 16, to oil pocket 13 fuel feeding, and then promote guiding valve 12 and move right, after guiding valve 12 moves to the precalculated position, can close control fuel tap 16 by fuel supply line 15 when needs load.When needs continue to load, can reopen control fuel tap 16, and then fuel feeding, after guiding valve 12 moves to next precalculated position, close control fuel tap 16 and get final product, as can be known by above analysis, can constantly load by closing bypass valve 17 and opening and closing control fuel tap 16, fully loaded until compressor; When needs unload, close control fuel tap 16, open bypass valve 17, to screw rod 11 oil extractions, guiding valve 12 is moved to the left oil pocket 13, after guiding valve 12 moves to the precalculated position, closes bypass valve 17 by low-pressure cavity 6.When needs continue unloading, can reopen bypass valve 17, to screw rod 11 oil extractions, after guiding valve 12 moves to next precalculated position, close bypass valve 17 and get final product, as the above analysis, can constantly unload by closing control fuel tap 16 and opening and closing bypass valve 17.The above analysis as can be known, by regulating the switching of control fuel tap 16 and bypass valve 17, can make guiding valve 12 move and stop to the arbitrary position, be that the step-less adjustment compressor that is used for handpiece Water Chilling Units of the present invention can be realized step-less adjustment, and then can make the screw-type water chiller of using compressor of the present invention realize stepless capacity regulating.In addition, because control fuel tap 16 and bypass valve 17 all are solenoid valve, can be by the switching of central control system control control fuel tap 16 and bypass valve 17, and then can be according to the actual load value of handpiece Water Chilling Units, in time dynamically adjust the switching of control fuel tap 16 and bypass valve 17, to realize that handpiece Water Chilling Units is carried out accurate capacity regulating, reach purpose of energy saving.
For when oil pocket 13 carries out fuel feeding, be convenient to the flow of oil is controlled, on the described fuel supply line 15 capillary tube 1 is installed.
Energy-conservation in order further to carry out, on the basis of using compressor of the present invention, according to following method compressor is carried out Load Control, according to chilled water target water-exit temperature T, the actual water-exit temperature T0 of compensation temperature Δ t and chilled water is specially by the switching of pulse signal adjustment control fuel tap 16 and bypass valve 17:
As T0 〉=T+ Δ t, close bypass valve 17, open control fuel tap 16, make compressor loads;
As T-Δ t＞T0＞T+ Δ t, close bypass valve 17 and control fuel tap 16, make compressor be positioned at load and keep the stage;
As T0≤T-Δ t, open bypass valve 17, close control fuel tap 16, make compressor unloading;
Wherein, Δ t is 0.1～1 ℃.
In order to improve control accuracy, the pulse width of described pulse signal is 0.5～1 second, is spaced apart 0.5～1 second.Highi degree of accuracy loads and unloading pulse control, help making the load of compressor between 50%～100%, to carry out the highi degree of accuracy step-less adjustment, in this interval, carry out the highi degree of accuracy step-less adjustment, help energy saving, wherein, the load of compressor is 100% o'clock, be compressor full load operation, this moment, guiding valve 12 moved to low order end, by that analogy, can control the load of compressor by the position of guiding valve 12.The position of guiding valve 12 can be determined by the following method: give pulse signal to the control fuel tap, calculating is worked as guiding valve 12 and is steadily moved to low order end, be the required umber of pulse N that applies of compressor full load, then, during each the loading, the umber of pulse that applies is counted, by the umber of pulse that applies and the ratio of N, the particular location that can show guiding valve 12, and then the load of may command compressor; Unloading situation and loading classes are seemingly.
For prolonging compressor of the present invention working life, the load of general compressor is only made startup and shutdown 0～25% and is used; And load or unload is also unsuitable oversize working time in 25%～50% interval, is recommended in and does step-less adjustment and Load Control in 50%～100% interval.Specifically calculate with coupling by load and find that the Load Control that makes compressor of the present invention is between 70%～90%, promptly compressor moves during the high-performance coefficient, like this can be more energy-conservation.
The handpiece Water Chilling Units of compressor of the present invention and application compressor of the present invention can be used for the place that constant temperature and humidity, temperature accuracy are had relatively high expectations, for example laboratory, hospital and accurate factory. Calculate and coupling by load, make compressor operating of the present invention between 70%～90%, the superior performance coefficient is arranged, use above-mentioned load controlled method, 4 grades of appearances are compared to existing technology transferred handpiece Water Chilling Units, can save energy more than 5%.
Claims (5)
1. the step-less adjustment compressor that is used for handpiece Water Chilling Units, comprise low-pressure cavity (6), oil pocket (13), oil strainer (10) and oil-way system, it is characterized in that: described oil-way system is made up of fuel supply line (15) and bypass tube (14), control fuel tap (16) is installed on the described fuel supply line (15), and an end of fuel supply line (15) is communicated with oil strainer (10), and the other end is communicated with oil pocket (13); Bypass valve (17) is installed on the described bypass tube (14), and an end of bypass tube (14) is communicated with oil pocket (13), and the other end is communicated with low-pressure cavity (6).
2. the step-less adjustment compressor that is used for handpiece Water Chilling Units as claimed in claim 1 is characterized in that: capillary tube (1) is installed on the described fuel supply line (15).
3. the step-less adjustment compressor that is used for handpiece Water Chilling Units as claimed in claim 1 or 2 is characterized in that: described control fuel tap (16) and bypass valve (17) all are solenoid valve.
4. load controlled method, it is characterized in that: comprise the described step-less adjustment compressor that is used for handpiece Water Chilling Units of claim 3, according to chilled water target water-exit temperature T, the actual water-exit temperature T0 of compensation temperature Δ t and chilled water is specially by the switching of pulse signal adjustment control fuel tap (16) and bypass valve (17):
As T0 〉=T+ Δ t, close bypass valve (17), open control fuel tap (16), make compressor loads;
As T-Δ t＞T0＞T+ Δ t, close bypass valve (17) and control fuel tap (16), make compressor be positioned at load and keep the stage;
As T0≤T-Δ t, open bypass valve (17), close control fuel tap (16), make compressor unloading;
Wherein, Δ t is 0.1～1 ℃.
5. load controlled method as claimed in claim 4 is characterized in that: the pulse width of described pulse signal is 0.5～1 second, is spaced apart 0.5～1 second.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011100385636A CN102094817A (en) | 2011-02-15 | 2011-02-15 | Infinitely variable control compressor for water chiller and loading control method for infinitely variable control compressor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011100385636A CN102094817A (en) | 2011-02-15 | 2011-02-15 | Infinitely variable control compressor for water chiller and loading control method for infinitely variable control compressor |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102410680A (en) * | 2011-10-30 | 2012-04-11 | 合肥天鹅制冷科技有限公司 | Control method for thermal load response of water chilling unit |
| CN104215008A (en) * | 2014-10-08 | 2014-12-17 | 烟台荏原空调设备有限公司 | Method and system of capacity regulation of screw refrigerator |
| CN104406339B (en) * | 2013-11-12 | 2018-03-06 | 江苏春兰动力制造有限公司 | A kind of single screw compressor continuative energy adjustment control method |
| CN111255691A (en) * | 2020-01-15 | 2020-06-09 | 珠海格力电器股份有限公司 | Screw compressor system capable of accurately regulating and controlling load, control method and air conditioner |
| CN111255692A (en) * | 2020-01-15 | 2020-06-09 | 珠海格力电器股份有限公司 | Screw compressor system capable of accurately adjusting load, control method and air conditioner |
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| CN2556393Y (en) * | 2002-05-15 | 2003-06-18 | 烟台冰轮股份有限公司 | Energy-regulating mechanism of helical-lobe compressor |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102410680A (en) * | 2011-10-30 | 2012-04-11 | 合肥天鹅制冷科技有限公司 | Control method for thermal load response of water chilling unit |
| CN102410680B (en) * | 2011-10-30 | 2013-06-19 | 合肥天鹅制冷科技有限公司 | Method for controlling thermal load response of water chilling unit |
| CN104406339B (en) * | 2013-11-12 | 2018-03-06 | 江苏春兰动力制造有限公司 | A kind of single screw compressor continuative energy adjustment control method |
| CN104215008A (en) * | 2014-10-08 | 2014-12-17 | 烟台荏原空调设备有限公司 | Method and system of capacity regulation of screw refrigerator |
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| CN111255691A (en) * | 2020-01-15 | 2020-06-09 | 珠海格力电器股份有限公司 | Screw compressor system capable of accurately regulating and controlling load, control method and air conditioner |
| CN111255692A (en) * | 2020-01-15 | 2020-06-09 | 珠海格力电器股份有限公司 | Screw compressor system capable of accurately adjusting load, control method and air conditioner |
| CN111255692B (en) * | 2020-01-15 | 2021-02-19 | 珠海格力电器股份有限公司 | Control method of screw compressor system capable of accurately adjusting load |
| CN111255691B (en) * | 2020-01-15 | 2021-07-02 | 珠海格力电器股份有限公司 | Screw compressor system capable of accurately regulating and controlling load, control method and air conditioner |
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Application publication date: 20110615 |