CN117091238A - Anti-freezing control method for operation of serial two-unit supply system - Google Patents
Anti-freezing control method for operation of serial two-unit supply system Download PDFInfo
- Publication number
- CN117091238A CN117091238A CN202310767106.3A CN202310767106A CN117091238A CN 117091238 A CN117091238 A CN 117091238A CN 202310767106 A CN202310767106 A CN 202310767106A CN 117091238 A CN117091238 A CN 117091238A
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- temperature
- water
- preset value
- freezing
- control
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- 238000007710 freezing Methods 0.000 title claims abstract description 60
- 238000000034 method Methods 0.000 title claims abstract description 25
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 100
- 229910052731 fluorine Inorganic materials 0.000 claims description 46
- 239000011737 fluorine Substances 0.000 claims description 46
- 239000003507 refrigerant Substances 0.000 claims description 34
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims description 30
- 238000010438 heat treatment Methods 0.000 claims description 29
- 238000010257 thawing Methods 0.000 claims description 28
- 238000004378 air conditioning Methods 0.000 claims description 14
- 238000005057 refrigeration Methods 0.000 claims description 10
- 230000002528 anti-freeze Effects 0.000 claims description 8
- 230000005855 radiation Effects 0.000 claims description 8
- 238000007791 dehumidification Methods 0.000 claims description 4
- 230000009977 dual effect Effects 0.000 claims 2
- 230000008014 freezing Effects 0.000 description 10
- 230000002159 abnormal effect Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- -1 heaven Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 239000000243 solution Substances 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
- F24F11/00—Control or safety arrangements
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
- F24F11/41—Defrosting; Preventing freezing
- F24F11/42—Defrosting; Preventing freezing of outdoor units
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/89—Arrangement or mounting of control or safety devices
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The application relates to the technical field of air conditioners, and provides an anti-freezing control method for the operation of a serial two-in-one system, which is used for facilitating the anti-freezing protection of the serial two-in-one system. When the anti-freezing protection control is performed, different protection control methods are adopted according to different system operation modes, so that the control is more accurate and energy-saving.
Description
Technical Field
The application relates to the technical field of air conditioners, in particular to an operation anti-freezing control method of a serial two-in-one system.
Background
The air conditioner has solved the demand of user to ambient temperature, but because air conditioner bloies and winter ground temperature reasons such as lower, the travelling comfort of heating is not as warm as ground all the time. In recent years, the two-in-one system is developed rapidly, and the two-in-one system combines air conditioning refrigeration and floor heating, so that the comfort experience of users is truly improved.
The two-in-one system comprises three types of heaven, water, heaven, fluorine and earth fluorine, and the heaven, fluorine and earth water system is a two-in-one system formed by adding a ground heating heat exchange module (a ground heat exchange module containing a fluorine heat exchanger) or a water fluorine heat exchanger into the multi-split system. Because water or aqueous solution is adopted as the ground heating secondary refrigerant, the ground heating secondary refrigerant is easy to freeze and expand or block a water pipe in a low-temperature environment to cause system damage, and therefore, the ground heating secondary refrigerant needs to be subjected to anti-freezing protection.
The existing anti-freezing protection is mainly aimed at freezing water caused by refrigerant leakage of a water-fluorine heat exchanger during the refrigerating operation of a parallel two-in-one system. The parallel type two-in-one supply takes the water-fluorine heat exchanger as a special internal machine in parallel connection, and the refrigerant can not pass through the water-fluorine heat exchanger during air conditioner refrigeration and defrosting, namely, the inlet and outlet valves of the water-fluorine heat exchanger are closed to prevent the refrigerant from flowing, so that the problem of water freezing caused by leakage of the door valve is only considered. But the refrigerant of the serial two-in-one supply passes through the indoor unit and the water-fluorine heat exchanger in series, and the refrigerant always passes through the water-fluorine heat exchanger, so that the parallel two-in-one supply operation anti-freezing control method is completely different from the serial type, and the anti-freezing protection for the serial two-in-one supply system is not available in the current industry.
Disclosure of Invention
In order to facilitate the anti-freezing protection of the serial two-unit supply system, the application provides an operation anti-freezing control method of the serial two-unit supply system.
The application solves the problems by adopting the following technical scheme:
the method for controlling the operation of the tandem two-unit supply system comprises the following steps:
step 1, obtaining the circulating water temperature Tf_w, the refrigerant temperature Tf_r and the outdoor environment temperature Torr of a water-fluorine heat exchanger;
step 2, if the circulating water temperature Tf_w is less than or equal to a preset value Tf_w_0 or the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_0, anti-freezing fault control is performed;
if not, entering different anti-freezing protection control according to different operation modes:
when the operation mode is a first operation mode, the first anti-freezing control is operated;
when the operation mode is an air-conditioning heating mode, the second anti-freezing control is operated;
and when the operation mode is radiation heating, the third anti-freezing control is operated.
Further, the anti-freezing fault control specifically includes: the heat exchange unit water pump is forced to run, and the compressor, the indoor motor and the outdoor motor stop running.
Further, the first operation mode is: air conditioning dehumidification operation, air conditioning refrigeration operation or ground radiation refrigeration operation.
Further, the first antifreeze control specifically includes: when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_1, the water system enters anti-freezing protection, and the compressor is not increased in frequency;
when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_2, the compressor is subjected to frequency reduction, when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_4, the compressor is stopped to perform frequency reduction, and when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_3, the compressor is stopped to operate;
when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_5, the system exits the anti-freezing protection;
wherein Tf_r_3 < Tf_r_2 < Tf_r_1, tf_r_2 < Tf_r_4, and Tf_r_1 < Tf_r_5.
Further, the second antifreeze control specifically includes: judging whether defrosting is performed, if yes, performing defrosting control; if not, the water pump is started to operate when the outdoor ambient temperature Torr is less than or equal to a preset value Torr_0 and the water pump stopping duration time tpu_stop is more than or equal to a preset value tpu_stop_0, and the water pump is stopped to operate when the circulating water temperature Tf_w is more than or equal to a preset value Tf_w_1 and the duration time tw_0.
Further, the third antifreeze control specifically includes: judging whether defrosting is performed, if yes, performing defrosting control; if not, ending.
Further, the defrosting control specifically comprises: starting a water pump, closing an indoor fan, continuously heating the outdoor unit, detecting the temperature Tf_w of circulating water, starting defrosting after Tf_w is more than or equal to Tf_w_2 and lasts for tw_1 minutes, turning to heating operation after defrosting is finished, closing the water pump, and starting the indoor fan.
Further, the preset value Tf_w_0 is between 0 and 6 ℃, and the preset value Tf_r_0 is between-3 and 3 ℃.
Further, the preset value Tor_0 is between-2 and 5 ℃, the preset value Tf_w_1 is between 5 and 20 ℃, the preset time tpu_stop_0 is between 10 and 120min, and the preset time tw_0 is between 0 and 10 min.
Further, the circulating water temperature Tf_w is the minimum value of the water pipe inlet temperature, the water pipe outlet temperature, the water pipe inlet temperature and the water pipe outlet temperature of the water fluorine heat exchange module or the average value of the water pipe inlet temperature and the water pipe outlet temperature;
the refrigerant temperature Tf_r is the minimum value of the inlet temperature of the fluorine pipe, the outlet temperature of the fluorine pipe, the inlet temperature of the fluorine pipe and the outlet temperature of the fluorine pipe or the average value of the inlet temperature of the fluorine pipe and the outlet temperature of the fluorine pipe of the water fluorine heat exchange module.
Compared with the prior art, the application has the following beneficial effects: according to the application, the anti-freezing control of the water system in the running state of the serial two-in-one system is divided into the anti-freezing fault control and the anti-freezing protection control, so that the system can enter the anti-freezing protection control under normal conditions, and can be recovered after the protection exits, thereby ensuring the normal operation of the system, and the system can enter the anti-freezing fault control under abnormal conditions, and the water system is prevented from freezing fault and can not be recovered, thereby ensuring the system is not damaged when abnormal. When the anti-freezing protection control is performed, different protection control methods are adopted according to different system operation modes, so that the control is more accurate and energy-saving.
Drawings
FIG. 1 is a schematic diagram of a serial two-in-one system;
FIG. 2 is a flow chart of an anti-freezing control method for the operation of the tandem two-in-one system;
FIG. 3 is a first antifreeze control flow chart;
FIG. 4 is a second antifreeze control flow chart;
FIG. 5 is a third antifreeze control flow chart;
fig. 6 is a defrosting control flow chart.
Reference numerals: the outdoor unit comprises a 1-outdoor unit, a 2-indoor unit, a 3-water fluorine heat exchange unit, a 4-water pipe, a 5-water collecting and distributing device, a 6-floor heating coil pipe, a 7-fluorine pipe, a 101-outdoor environment temperature sensor, a 301-water-air heat exchanger, a 302-water pump, a 311-water pipe outlet sensor, a 312-water pipe inlet sensor, a 321-fluorine pipe outlet sensor, a 322-fluorine pipe inlet sensor and a 401-water pipe easy-freezing position sensor.
Detailed Description
The present application will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
As shown in fig. 1, the serial two-in-one supply system is formed by connecting an outdoor unit 1, an indoor unit 2, a water fluorine heat exchanger unit 3, a water collector 5 and a floor heating coil 6 in series through a water pipe 4 and a fluorine pipe 7, wherein the water fluorine heat exchanger unit 3 is provided with a water fluorine heat exchanger 301, a water pump 302, a water pipe outlet sensor 311, a water pipe inlet sensor 312, a fluorine pipe outlet sensor 321 and a fluorine pipe inlet sensor 322, the outdoor unit 1 is provided with an outdoor environment temperature sensor 101, and a water pipe freezing position sensor 401 is arranged at a water pipe freezing position.
As shown in fig. 2, the method for controlling the anti-freezing operation of the tandem two-in-one system comprises the following steps:
step 1, obtaining the circulating water temperature Tf_w, the refrigerant temperature Tf_r and the outdoor environment temperature Torr of a water-fluorine heat exchanger;
step 2, if the circulating water temperature tf_w is less than or equal to a preset value tf_w_0 or the refrigerant temperature tf_r is less than or equal to a preset value tf_r_0, performing anti-freezing fault control: the water pump of the heat exchange unit is forced to run, the compressor, the indoor motor and the outdoor motor stop running, and the system displays the water reporting system to prevent the freezing failure; the anti-freezing fault control is used for controlling and protecting the system from faults or abnormal conditions, such as the condition that a four-way valve is not reversed in the operation of a heating mode, the water system is blocked and cannot circulate or the flow is insufficient, and the like, and is effective in any operation mode; the system can not automatically recover under the control of the anti-freezing fault, and the anti-freezing fault can be reported; the preset value Tf_w_0 is between 0 and 6 ℃, such as the value of 2 ℃, and the preset value Tf_r_0 is between-3 and 3 ℃, such as the value of 0 ℃.
For example: the air conditioner heating mode is operated, but the four-way valve is not reversed due to the fact that the four-way valve is not electrified or blocked, at the moment, the two-way supply system is actually in the air conditioner refrigerating mode, the temperature of the refrigerant of the water-fluorine heat exchanger is rapidly reduced, when the temperature is lower than a preset value Tf_r_0, the two-way supply system starts a water pump to operate, a compressor, an indoor motor and an outdoor motor are closed, and the system displays the water reporting system to prevent freezing faults. The compressor is closed to cut off the power of the temperature reduction of the refrigerant, the water pump can utilize the ground heating pipe water and the heat stored indoors to heat the water-fluorine heat exchanger, the water reporting system is prevented from freezing, the user is informed of the system failure, the system cannot be used and maintained, the system cannot be automatically recovered, and the system is prevented from being frequently started to be damaged.
If not, different anti-freezing protection control is carried out according to different operation modes, the anti-freezing protection control is used for water system protection control when the two-in-one system normally operates, no fault is reported, after protection is carried out, the protection is automatically carried out when the conditions are met, and the system is restored to the starting state.
The method comprises the following steps: when the operation mode is the first operation mode, the first antifreeze control is operated as shown in fig. 3: when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_1, the water system enters anti-freezing protection, and the compressor is not increased in frequency;
when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_2, the compressor is subjected to frequency reduction, when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_4, the compressor is stopped to perform frequency reduction, and when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_3, the compressor is stopped to operate;
when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_5, the system exits the anti-freezing protection; wherein Tf_r_3 < Tf_r_2 < Tf_r_1, tf_r_2 < Tf_r_4, and Tf_r_1 < Tf_r_5.
The first mode of operation is: air conditioning dehumidification operation, air conditioning refrigeration operation or ground radiation refrigeration operation.
When the operation mode is the air conditioning heating mode, the second freezing prevention control is operated as shown in fig. 4: judging whether defrosting is performed, if yes, performing defrosting control; if not, the water pump is started to operate when the outdoor ambient temperature Torr is less than or equal to a preset value Torr_0 and the water pump stopping duration time tpu_stop is more than or equal to a preset value tpu_stop_0, and the water pump is stopped to operate when the circulating water temperature Tf_w is more than or equal to a preset value Tf_w_1 and the duration time tw_0.
The preset value Tor_0 is between-2 and 5 ℃, the preset value Tf_w_1 is between 5 and 20 ℃, the preset time tpu_stop_0 is between 10 and 120min, and the preset time tw_0 is between 0 and 10 min. As shown in fig. 4, when operating in the air conditioning and heating mode, the water system is not operated, and the water pipe exposed to the outside or the floor heating pipe of the unheated room may be frozen in a low temperature environment (the air conditioning indoor unit may be installed in one room), and the water system is heated by starting the water pump operation at intervals to ensure that the water system is not frozen. For energy saving, the preset value of the water pump stop duration can be set in segments or calculated according to a fitting formula according to the outdoor environment temperature Tor, so that the running time of the water pump is reduced as much as possible on the premise of ensuring no freezing.
When the operation mode is radiation heating, entering third anti-freezing control, judging whether defrosting or not as shown in fig. 5, and if yes, performing defrosting control; if not, ending.
As shown in fig. 6, the water-fluorine heat exchanger is in a low temperature state during defrosting, so that the water temperature is heated before defrosting in order not to freeze, and the water pump is operated during defrosting, thereby realizing the defrosting of the heat accumulated by the water system. The ground radiation heating mode is not needed to heat water temperature theoretically before defrosting, but in order to be unified with defrosting control of air conditioner heating, a water temperature heating detection process is added, and if the water temperature heating detection process is separated from defrosting process control of the air conditioner heating mode, heating and circulating water temperature judging processes before defrosting can be canceled.
Specifically, the first operation mode is: air conditioning dehumidification operation, air conditioning refrigeration operation or ground radiation refrigeration operation. The same preset value in the operation mode can be set according to actual needs and can be different. The preset value Tf_r_3 is between-2 and 6 ℃, such as the value of 1 ℃, tf_r_2 is between 0 and 8 ℃, such as the value of 4 ℃, tf_r_1 is between 2 and 10 ℃, such as the value of 7 ℃, tf_r_4 is between 2 and 10 ℃, such as the value of 6 ℃, and Tf_r_5 is between 4 and 15 ℃, such as the value of 9 ℃. As shown in fig. 3, the anti-freezing protection control is divided into three stages, wherein one stage is compressor non-frequency-raising protection (frequency-limiting protection), the second stage is compressor frequency-reducing protection, the third stage is compressor stop protection, the Tf_r temperature is ensured to be too low through the third stage protection, and meanwhile, the compressor frequency can stably run in a wider range, so that both reliable protection and system capacity play are realized.
The circulating water temperature Tf_w is any one of the minimum value, the average value or the two temperatures of the water pipe inlet temperature and the water pipe outlet temperature of the water-fluorine heat exchange module; the refrigerant temperature Tf_r is one of the minimum value, the average value or the two temperatures of the inlet temperature and the outlet temperature of the fluorine pipe of the water fluorine heat exchange module.
Claims (10)
1. The method for controlling the operation of the tandem two-unit supply system is characterized by comprising the following steps of:
step 1, obtaining the circulating water temperature Tf_w, the refrigerant temperature Tf_r and the outdoor environment temperature Torr of a water-fluorine heat exchanger;
step 2, if the circulating water temperature Tf_w is less than or equal to a preset value Tf_w_0 or the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_0, anti-freezing fault control is performed;
if not, entering different anti-freezing protection control according to different operation modes:
when the operation mode is a first operation mode, the first anti-freezing control is operated;
when the operation mode is an air-conditioning heating mode, the second anti-freezing control is operated;
and when the operation mode is radiation heating, the third anti-freezing control is operated.
2. The method for controlling the operation of the tandem two-in-one system according to claim 1, wherein the anti-freezing fault control is specifically: the heat exchange unit water pump is forced to run, and the compressor, the indoor motor and the outdoor motor stop running.
3. The tandem dual supply system operation antifreeze control method according to claim 1, wherein the first operation mode is: air conditioning dehumidification operation, air conditioning refrigeration operation or ground radiation refrigeration operation.
4. The method for controlling the operation of the tandem two-unit system according to claim 1, wherein the first anti-freezing control is specifically: when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_1, the water system enters anti-freezing protection, and the compressor is not increased in frequency;
when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_2, the compressor is subjected to frequency reduction, when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_4, the compressor is stopped to perform frequency reduction, and when the refrigerant temperature Tf_r is less than or equal to a preset value Tf_r_3, the compressor is stopped to operate;
when the refrigerant temperature Tf_r is more than or equal to a preset value Tf_r_5, the system exits the anti-freezing protection;
wherein Tf_r_3 < Tf_r_2 < Tf_r_1, tf_r_2 < Tf_r_4, and Tf_r_1 < Tf_r_5.
5. The method for controlling the operation of the tandem two-unit system according to claim 4, wherein the second anti-freezing control is specifically: judging whether defrosting is performed, if yes, performing defrosting control; if not, the water pump is started to operate when the outdoor ambient temperature Torr is less than or equal to a preset value Torr_0 and the water pump stopping duration time tpu_stop is more than or equal to a preset value tpu_stop_0, and the water pump is stopped to operate when the circulating water temperature Tf_w is more than or equal to a preset value Tf_w_1 and the duration time tw_0.
6. The method for controlling the operation of the tandem two-unit system according to claim 5, wherein the third anti-freezing control is specifically: judging whether defrosting is performed, if yes, performing defrosting control; if not, ending.
7. The method for controlling the operation of the tandem two-in-one system according to claim 6, wherein the defrosting control is specifically: starting a water pump, closing an indoor fan, continuously heating the outdoor unit, detecting the temperature Tf_w of circulating water, starting defrosting after Tf_w is more than or equal to Tf_w_2 and lasts for tw_1 minutes, turning to heating operation after defrosting is finished, closing the water pump, and starting the indoor fan.
8. The method for controlling the operation of the tandem two-supply system according to claim 7, wherein the preset value tf_w_0 is between 0 and 6 ℃, and the preset value tf_r_0 is between-3 and 3 ℃.
9. The method for controlling the operation of the tandem dual supply system according to claim 7, wherein the preset value tor_0 is between-2 and 5 ℃, the preset value tf_w_1 is between 5 and 20 ℃, the preset time tpu_stop_0 is between 10 and 120min, and the preset time tw_0 is between 0 and 10 min.
10. The method for controlling the operation of the tandem two-unit system according to any one of claims 1 to 9, wherein the circulating water temperature tf_w is a minimum value of a water pipe inlet temperature, a water pipe outlet temperature, a water pipe inlet temperature and a water pipe outlet temperature of the water fluorine heat exchange module or an average value of the water pipe inlet temperature and the water pipe outlet temperature;
the refrigerant temperature Tf_r is the minimum value of the inlet temperature of the fluorine pipe, the outlet temperature of the fluorine pipe, the inlet temperature of the fluorine pipe and the outlet temperature of the fluorine pipe or the average value of the inlet temperature of the fluorine pipe and the outlet temperature of the fluorine pipe of the water fluorine heat exchange module.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310767106.3A CN117091238A (en) | 2023-06-27 | 2023-06-27 | Anti-freezing control method for operation of serial two-unit supply system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310767106.3A CN117091238A (en) | 2023-06-27 | 2023-06-27 | Anti-freezing control method for operation of serial two-unit supply system |
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| CN202310767106.3A Pending CN117091238A (en) | 2023-06-27 | 2023-06-27 | Anti-freezing control method for operation of serial two-unit supply system |
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- 2023-06-27 CN CN202310767106.3A patent/CN117091238A/en active Pending
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