CN114739081A - Air conditioning unit control method and system and air conditioning unit - Google Patents
Air conditioning unit control method and system and air conditioning unit Download PDFInfo
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- 238000004378 air conditioning Methods 0.000 title claims abstract description 85
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000001704 evaporation Methods 0.000 claims abstract description 123
- 230000008020 evaporation Effects 0.000 claims abstract description 122
- 230000008859 change Effects 0.000 claims abstract description 93
- 230000000630 rising effect Effects 0.000 claims abstract description 14
- 238000001514 detection method Methods 0.000 claims description 85
- 238000005057 refrigeration Methods 0.000 claims description 20
- 238000012937 correction Methods 0.000 claims description 18
- 230000001965 increasing effect Effects 0.000 claims description 11
- 230000001603 reducing effect Effects 0.000 claims description 7
- 230000003750 conditioning effect Effects 0.000 abstract description 7
- 239000007788 liquid Substances 0.000 description 20
- 230000009467 reduction Effects 0.000 description 14
- 230000000694 effects Effects 0.000 description 5
- 238000001816 cooling Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000003507 refrigerant Substances 0.000 description 2
- 230000001960 triggered effect Effects 0.000 description 2
- 235000013361 beverage Nutrition 0.000 description 1
- 235000013365 dairy product Nutrition 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 235000012055 fruits and vegetables Nutrition 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 230000001932 seasonal effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000002277 temperature effect Effects 0.000 description 1
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- 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
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D11/00—Self-contained movable devices, e.g. domestic refrigerators
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- 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
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D29/00—Arrangement or mounting of control or safety devices
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
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Abstract
The invention discloses an air conditioning unit control method, a control system and an air conditioning unit.A compressor is controlled to reduce the frequency by periodically detecting the evaporation pressure and when the evaporation pressure is detected to be reduced and the change rate of the evaporation pressure is greater than a change rate threshold value; when the rising of the evaporation pressure is detected and the change rate of the evaporation pressure is larger than the change rate threshold value, controlling the compressor to increase the frequency; the air conditioner has the advantages that the compressor is prevented from triggering the low-voltage protection to stop, the air conditioning effect is guaranteed, the problem that the compressor is frequently started and stopped is solved, the temperature control precision of the indoor unit is improved, and the reliability of the air conditioning unit is improved.
Description
Technical Field
The invention belongs to the technical field of air conditioning, and particularly relates to an air conditioning unit control method, an air conditioning unit control system and an air conditioning unit.
Background
With the development of economy, the living standard of people is greatly improved, and the freezing and refrigerating technology is widely applied. More and more commercial super-configured refrigerated cabinets are used for refreshing and storing dairy products, beverages, seasonal fruits and vegetables, and the product quality is improved. A plurality of refrigerated display cabinets are generally arranged in a business supermarket, and a one-to-many mode is generally adopted for an outdoor unit of a condensing unit due to unit power, namely, a plurality of refrigerated cabinets are arranged outside one outdoor condensing unit.
Because the article kind or the shipment volume of placing of different freezer are different, it is different that it reaches target settlement temperature shut down moment, and some refrigerated display cabinets reach settlement temperature and shut down, and some refrigerated display cabinets load is great not satisfy shutdown temperature and continue the operation phenomenon. The whole system load has great change at the in-process that the freezer opens and stops, and whole refrigerating system causes great fluctuation, closes because of certain or several freezers and stops, and evaporation side area reduces, and outside condensing unit evaporating pressure sharply descends, causes unit compressor low pressure protection to shut down, and the refrigerated display cabinet refrigeration effect variation that is moving causes the accuse temperature effect poor, and temperature fluctuation in the cabinet. The triggering protection of the compressor of the outside condensing unit influences the service life of the compressor.
Aiming at the problems, no effective solution is available at present for solving the problems, and the operation of the whole unit system is maintained only by means of frequent starting and stopping of the compressor of the outer-side condensing unit under the condition that the service life reliability of the unit is sacrificed.
Disclosure of Invention
The invention provides a control method of an air conditioning unit, which solves the problem of frequent start and stop of a compressor.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
the control method of the air conditioning unit comprises an outdoor unit and a plurality of indoor units, wherein each indoor unit is connected with the outdoor unit; the control method comprises the following steps:
periodically detecting the evaporation pressure;
when the evaporation pressure is reduced and the change rate is greater than the change rate threshold value, controlling the compressor to reduce the frequency;
and when the evaporation pressure rises and the change rate is larger than the change rate threshold value, controlling the compressor to increase the frequency.
In some embodiments of the present application, when the compressor is controlled to perform the frequency reduction, the target operating frequency N1 of the compressor is:
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, a correction coefficient;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
In some embodiments of the present application, when the compressor is controlled to increase frequency, the target operating frequency N2 of the compressor is:
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
In some embodiments of the present application, the change rate threshold is a preset fixed value; or,
rate of change threshold = K3 × Ps 1;
wherein,
k3, correction factor;
ps1, the evaporation pressure change rate at which all indoor units are operated.
In some embodiments of the present application, when the compressor is controlled to perform the frequency reduction, the compressor is controlled to perform the frequency reduction at the second speed;
when the compressor is controlled to be subjected to frequency rising, the compressor is controlled to be subjected to frequency rising at a second speed;
wherein the second speed > the first speed;
the first speed is the compressor frequency increasing or reducing speed when all indoor units are operated.
The air conditioning unit control system comprises an outdoor unit and a plurality of indoor units, wherein each indoor unit is connected with the outdoor unit; the control system includes:
the evaporation pressure detection module is used for periodically detecting the evaporation pressure;
the calculation module is used for calculating the change rate of the evaporation pressure;
a judgment module for
When the evaporation pressure is reduced and the change rate is greater than the change rate threshold value, controlling the compressor to reduce the frequency;
and when the evaporation pressure rises and the change rate is larger than the change rate threshold value, controlling the compressor to increase the frequency.
In some embodiments of the present application, the air conditioning unit control system further includes:
the target operating frequency calculation module is used for calculating a target operating frequency N1 when the compressor is subjected to frequency reduction;
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
The method is also used for calculating a target running frequency N2 when the compressor is subjected to frequency rising;
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
In some embodiments of the present application, the air conditioning unit control system further includes:
a rate of change threshold calculation module to calculate a rate of change threshold = K3 × Ps 1;
wherein,
k3, correction factor;
ps1, the evaporation pressure change rate at which all indoor units are operated.
An air conditioning assembly comprising:
an outdoor unit;
a plurality of indoor units, each of which is connected with the outdoor unit;
a controller for performing the air conditioning unit control method as claimed in any one of claims 1 to 5.
In some embodiments of the present application, the indoor unit is disposed in a refrigerated display cabinet.
Compared with the prior art, the invention has the advantages and positive effects that: according to the air conditioning unit control method, the air conditioning unit control system and the air conditioning unit, the evaporation pressure is periodically detected, and when the evaporation pressure is detected to be reduced and the change rate of the evaporation pressure is greater than the change rate threshold value, the compressor is controlled to reduce the frequency; when the rising of the evaporation pressure is detected and the change rate of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to increase the frequency; the air conditioner has the advantages that the compressor is prevented from triggering the low-voltage protection to stop, the air conditioning effect is guaranteed, the problem that the compressor is frequently started and stopped is solved, the temperature control precision of the indoor unit is improved, and the reliability of the air conditioning unit is improved.
Other features and advantages of the present invention will become more apparent from the detailed description of the embodiments of the present invention when taken in conjunction with the accompanying drawings.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of an air conditioning unit according to the present invention;
FIG. 2 is a flow chart of an embodiment of an air conditioning unit control method according to the present invention;
fig. 3 is a block diagram of an embodiment of an air conditioning unit control system according to the present invention.
Reference numerals are as follows:
TV1, thermostatic expansion valve; TV2, thermostatic expansion valve; TVn thermal expansion valve;
EV1, solenoid valve; EV2, solenoid valve; EVn, electromagnetic valve;
j1, liquid tube stop valve; j2, air tube stop valve;
sensor, low pressure Sensor;
switch, high voltage Switch;
filter, dry Filter;
G. a liquid viewing mirror.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without making any creative effort belong to the protection scope of the present application.
In the description of the present application, it is to be understood that the terms "central," "upper," "lower," "front," "back," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the figures, which are based on the orientations and positional relationships shown in the figures, and are used for convenience in describing the present application and for simplicity in description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be considered limiting.
In the description of the present application, it is to be understood that the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or as implying that the number of indicated technical features is indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.
In the description of the present application, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
Aiming at the problem of frequent starting and stopping of the compressor, the invention provides an air conditioning unit control method, an air conditioning unit control system and an air conditioning unit, which solve the problem of frequent starting and stopping of the compressor and improve the temperature control effect of the air conditioning unit. Hereinafter, an air conditioning unit control method, an air conditioning unit control system, and an air conditioning unit according to the present invention will be described in detail with reference to the accompanying drawings.
The first embodiment,
The air conditioning unit comprises an outdoor unit and a plurality of indoor units. The indoor units are connected in parallel, and each indoor unit is connected with the outdoor unit. The liquid pipe of each indoor unit is connected with the liquid pipe of the outdoor unit, and the air pipe of each indoor unit is connected with the air pipe of the outdoor unit, as shown in fig. 1.
The outdoor unit comprises a compressor, an outdoor heat exchanger, a high-pressure liquid storage device, a gas-liquid separator, a high-pressure Switch, a drying Filter, a liquid sight glass G, a low-pressure Sensor, a liquid pipe stop valve J1, an air pipe stop valve J2 and the like.
The liquid pipe of each indoor machine is provided with a thermostatic expansion valve and an electromagnetic valve. The thermostatic expansion valve is used for throttling the refrigerant; the electromagnetic valve is controlled by the controller to act, and when the actual temperature reaches the target value, the electromagnetic valve is closed.
A thermostatic expansion valve TV1 and an electromagnetic valve EV1 are arranged on a liquid pipe of the indoor unit 1;
a thermostatic expansion valve TV2 and an electromagnetic valve EV2 are arranged on a liquid pipe of the indoor unit 2;
……；
a thermostatic expansion valve TVn and an electromagnetic valve EVn are arranged on a liquid pipe of the indoor unit N.
The outdoor unit is provided with a variable frequency compressor, the frequency of the compressor can automatically adjust the frequency increasing or reducing action according to the target evaporation pressure Ps0 of the system, and the air conditioning unit is ensured to operate within the range of the target evaporation pressure deviation delta Ps.
The low-pressure Sensor can detect the real-time evaporation pressure Ps of the air conditioning unit in real time, compares the real-time evaporation pressure Ps with the target evaporation pressure Ps0, and controls the frequency increasing or frequency reducing action of the compressor, so that the evaporation pressure of the air conditioning unit is stably operated between Ps0+ delta Ps, wherein Ps is more than or equal to Ps 0-delta Ps.
The control method of the air conditioning unit of the invention periodically detects the evaporation pressure; when the reduction of the evaporation pressure is detected and the change rate (reduction rate) of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to reduce the frequency; when the rise of the evaporation pressure is detected and the rate of change of the evaporation pressure (rise rate) is greater than the rate of change threshold, the compressor is controlled to be increased in frequency.
The air conditioning unit control method mainly comprises the following steps, and is shown in figure 2.
And in the running process of the air conditioning unit, the low-pressure Sensor is used for periodically detecting the evaporation pressure.
Step S1: the evaporation pressure is detected.
Step S2: and calculating the difference value between the evaporation pressure detected in the detection period and the evaporation pressure detected in the previous detection period, and calculating the change rate of the evaporation pressure.
The difference = the evaporation pressure detected in the present detection cycle — the evaporation pressure detected in the previous detection cycle;
rate of change = absolute value of difference/detection period T.
Step S3: and controlling the operation of the compressor according to the difference value and the change rate.
When the difference is less than 0 and the change rate (reduction rate) is greater than the change rate threshold, indicating that the evaporation pressure is rapidly reduced, the compressor is controlled to rapidly reduce the frequency, and the compressor is prevented from triggering low-pressure protection to stop.
When the difference value is greater than 0 and the change rate (rise rate) is greater than the change rate threshold value, the evaporation pressure rises rapidly, and then the compressor is controlled to rise rapidly, so that the air conditioning effect is prevented from being poor.
According to the control method of the air conditioning unit, the evaporation pressure is detected periodically, and when the evaporation pressure is detected to be reduced and the change rate of the evaporation pressure is greater than the change rate threshold value, the compressor is controlled to reduce the frequency; when the rising of the evaporation pressure is detected and the change rate of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to increase the frequency; the air conditioner has the advantages that the compressor is prevented from triggering the low-voltage protection to stop, the air conditioning effect is guaranteed, the problem that the compressor is frequently started and stopped is solved, the temperature control precision of the indoor unit is improved, and the reliability of the air conditioning unit is improved.
In some embodiments of the present application, when the rate of decrease of the evaporation pressure is greater than the rate of change threshold and the compressor is controlled to be down-clocked, the target operating frequency N1 of the compressor is:
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, is a correction coefficient. 0 < k 1. ltoreq.1, and k1 may be any of the above ranges. Of course, the value of k1 can be optimized and adjusted according to actual conditions.
Nqyc, the compressor operating frequency of the last detection cycle; i.e. the compressor operating frequency before a sudden change in the evaporation pressure.
And Psqyc, which is the evaporation pressure detection value of the last detection cycle.
And Psdq, which is the evaporation pressure detection value of the current detection period.
And determining the target operation frequency of the compressor according to the operation frequency of the compressor in the last detection period and the reduction percentage of the evaporation pressure, so that the more reasonable target operation frequency of the compressor can be determined, and the compressor is prevented from stopping.
In some embodiments of the present application, when the rising rate of the evaporation pressure is greater than the threshold rate of change and the compressor is controlled to rise, the target operating frequency N2 of the compressor is:
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, a correction coefficient. 1. ltoreq. k 2. ltoreq.2, and k2 may take any value within the above range. Of course, the value of k2 can be optimized and adjusted according to actual conditions.
Nqyc, the compressor operating frequency of the last detection cycle; i.e. the compressor operating frequency before a sudden change in the evaporation pressure.
And Psqyc, which is the evaporation pressure detection value of the last detection cycle.
And Psdq, which is the evaporation pressure detection value of the current detection period.
And determining the target operation frequency of the compressor according to the operation frequency of the compressor in the previous detection period and the evaporation pressure ratio of the current detection period and the previous detection period, so that the more reasonable target operation frequency of the compressor can be determined, and the refrigeration effect of the air conditioning unit is ensured.
In some embodiments of the application, the change rate threshold is a preset fixed value, which is simple and convenient, and can directly judge whether the compressor needs to increase frequency or decrease frequency.
In other embodiments of the present application, the rate of change threshold = K3 × Ps 1;
wherein,
k3, correction factor. 1 < K3 < 3, K3 may assume any of the above-mentioned ranges. Of course, the value of k3 can be optimized and adjusted according to actual conditions. In some embodiments of the present application, K3= 2. I.e., the rate of change threshold =2 × Ps 1.
Ps1, the evaporation pressure change rate at which all indoor units are operated.
When the indoor unit is completely started to operate, the low-pressure Sensor of the outdoor unit detects the evaporation low-pressure Ps of the air conditioning unit in real time, calculates the change rate Ps1 of the evaporation low-pressure when the indoor unit is completely started, and controls the compressor to perform frequency increasing or frequency reducing operation at the first speed L1 (unit Hz/s) so that the evaporation pressure of the air conditioning unit is stably operated between Ps 0-delta Ps-Ps and Ps0+ delta Ps.
The change rate Ps1= | (the evaporation pressure detection value of the current detection period-the evaporation pressure detection value of the previous detection period)/the detection period T |, that is, the change rate Ps1 is an absolute value obtained after the change difference value of the unit time is calculated.
The detection period T defaults to 0.5 seconds.
In some embodiments of the present application, K3=2, i.e. the rate of change threshold =2 × Ps 1.
By determining the change rate threshold value through the change rate Ps1, a more accurate change rate threshold value can be determined according to the actual operation of the air conditioning unit.
In some embodiments of the present application, the first and second,
when the compressor is controlled to be in the frequency reduction state, the compressor is controlled to be in the frequency reduction state at the second speed L2, namely the compressor is controlled to be in the frequency reduction state rapidly, and the compressor is prevented from triggering low-pressure protection shutdown.
When the compressor is controlled to be increased in frequency, the compressor is controlled to be increased in frequency at a second speed L2, namely, the compressor is controlled to be increased in frequency quickly, and the air conditioning effect is prevented from being poor.
Wherein the second speed is greater than the first speed; the first speed is the compressor frequency increasing or reducing speed when all indoor units are operated. I.e. the first speed is the normal operation fm speed and the second speed is the pressure surge fm speed.
In some embodiments of the present application, the indoor unit is disposed in the refrigerator, and the air conditioning unit performs a cooling operation to provide cooling capacity for the refrigerator. That is, one outdoor unit drives a plurality of refrigerated cabinets to refrigerate the plurality of refrigerated cabinets.
A plurality of refrigerating display cabinet bodies are arranged at the indoor side according to the actual application requirements of the business surpasses, and a thermostatic expansion valve (namely a thermostatic expansion valve on a liquid pipe of an indoor machine) is configured on a liquid pipe of each refrigerating display cabinet body for throttling the refrigerant; the electromagnetic valve is controlled by a controller (namely an indoor machine controller) of the refrigeration display cabinet to act, when the real-time cabinet temperature T is less than a target set value (Ts-delta T), the electromagnetic valve is controlled to be closed, namely the refrigeration display cabinet reaches the target set value, the electromagnetic valve is closed, liquid is supplied through the liquid cutoff pipe, the refrigeration display cabinet quits the system operation, namely the evaporation side area of the whole system is reduced, the evaporation pressure of the whole system is sharply reduced at the moment of liquid supply through the liquid cutoff pipe, a compressor of a conventional product is triggered to protect and shut down, and the temperature control precision of the refrigeration display cabinet in operation is poor; when the real-time cabinet temperature T > (Ts + delta T), the temperature of the body of the refrigeration display cabinet is higher, the electromagnetic valve corresponding to the refrigeration display cabinet is controlled to be opened, and liquid supply at the liquid pipe side is recovered to carry out refrigeration operation.
Ts: the target temperature control temperature set by the controller of the refrigeration display cabinet has different numerical value set values of different cabinets.
Δ T: the temperature control precision value set by the controller of the refrigeration display cabinet can be different according to the value set values of different cabinets.
During the continuous operation of the air conditioning unit, part of the refrigeration display cabinets gradually reach the set target storage temperature, the refrigeration display cabinets are stopped and the electromagnetic valves are closed, if the change rate of the evaporation low-pressure at the moment is detected and calculated to be greater than 2 Ps1, and the evaporation pressure detection value Psdq in the detection period is smaller than the evaporation pressure detection value Psqyc in the previous detection period, namely the evaporation pressure is detected to drop rapidly, the compressor is controlled to carry out fast frequency reduction according to the speed of the second speed L2Hz/s, and the frequency of the compressor is N1= k1 Nqyc (Psqyc-Psdq)/Psqyc in a frequency reduction target mode. Realize promptly fast falling the frenquency, avoid closing because of the cold-stored show cupboard of indoor side and lead to the compressor to trigger the low pressure protection and shut down, and then avoid causing the refrigeration to interrupt because of the compressor shuts down and influence the temperature control precision and the compressor reliability at the operation show cupboard.
And in the process of continuously operating the air conditioning unit, the temperature of the partially stopped refrigerated display cabinet rises again, the electromagnetic valve is opened after the opening condition is triggered, at the moment, if the change rate of the evaporation low pressure is larger than 2 Ps1 at the moment, and the evaporation pressure detection value Psdq in the detection period is larger than that in the previous detection period, namely, the rapid rise of the evaporation pressure is detected, the compressor is controlled to rapidly increase the frequency at the speed of a second speed L2Hz/s, and the frequency increase target frequency of the compressor is N2= k2 Nqyc Psdq/Psqyc. Realize quick rising promptly frequently, the refrigerated display cabinet that stops opens once more and puts into operation through the mode of quick rising frequently, realizes rapid cooling, avoids the cabinet body of rerunning poor effect because of the cooling is not enough.
The control method of the air conditioning unit avoids the problem that the service life is affected by frequent triggering protection starting and stopping of the compressor, and meanwhile improves the temperature control precision of the refrigeration display cabinet and the quality of the refrigeration product.
The air conditioning unit control method of the embodiment improves the product reliability and prolongs the service life of the unit; the temperature control precision of the indoor unit is improved, and the product quality is improved.
Example II,
Based on the design of the air conditioning unit control method in the first embodiment, the second embodiment provides an air conditioning unit control system.
The air conditioning unit includes an outdoor unit and a plurality of indoor units, each of which is connected to the outdoor unit, as shown in fig. 1.
The air conditioning unit control system of the present embodiment includes an evaporation pressure detection module, a calculation module, a determination module, and the like, as shown in fig. 3.
And the evaporation pressure detection module is used for periodically detecting the evaporation pressure.
And the calculating module is used for calculating the change rate of the evaporation pressure.
A judgment module for
When the evaporation pressure is reduced and the change rate is greater than the change rate threshold value, controlling the compressor to reduce the frequency;
and when the evaporation pressure rises and the change rate is larger than the change rate threshold value, controlling the compressor to increase the frequency.
In some embodiments of the present application, the air conditioning unit control system further includes a target operating frequency calculation module.
The target operating frequency calculation module is used for calculating a target operating frequency N1 when the compressor is subjected to frequency reduction;
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, is a correction coefficient. 0 < k 1. ltoreq.1, and k1 may be any of the above ranges. Of course, the value of k1 can be optimized and adjusted according to actual conditions.
Nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the detected value of the evaporation pressure in the current detection period.
The target operation frequency calculation module is also used for calculating a target operation frequency N2 when the compressor is subjected to frequency raising;
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, correction factor. 1. ltoreq. k 2. ltoreq.2, and k2 may take any value within the above range. Of course, the value of k2 can be optimized and adjusted according to actual conditions.
Nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
In some embodiments of the present application, the air conditioning unit control system further includes a change rate threshold calculation module.
A change rate threshold calculation module for calculating a change rate threshold = K3 × Ps 1;
wherein,
k3, correction factor. 1 < K3 < 3, K3 may assume any of the above-mentioned ranges. Of course, the value of k3 can be optimized and adjusted according to actual conditions.
Ps1, the evaporation pressure rate of change when all indoor units are operating.
The working process of the air conditioning unit control system has been described in detail in the air conditioning unit control method according to the first embodiment, and is not described herein again.
The air conditioning unit control system of the embodiment periodically detects the evaporation pressure, and controls the compressor to reduce the frequency when the evaporation pressure is detected to be reduced and the change rate of the evaporation pressure is greater than the change rate threshold; when the rising of the evaporation pressure is detected and the change rate of the evaporation pressure is larger than the change rate threshold value, controlling the compressor to increase the frequency; the air conditioner has the advantages that the compressor is prevented from triggering the low-voltage protection to stop, the air conditioning effect is guaranteed, the problem that the compressor is frequently started and stopped is solved, the temperature control precision of the indoor unit is improved, and the reliability of the air conditioning unit is improved.
Example III,
Based on the design of the control method of the air conditioning unit in the first embodiment, the third embodiment provides an air conditioning unit, which comprises an outdoor unit, a plurality of indoor units and a controller; each indoor unit is connected with the outdoor unit respectively; as shown in fig. 1.
And the controller is used for executing the air conditioning unit control method in the first embodiment.
According to the air conditioning unit, the evaporation pressure is periodically detected, and when the evaporation pressure is detected to be reduced and the change rate of the evaporation pressure is greater than the change rate threshold value, the compressor is controlled to reduce the frequency; when the rising of the evaporation pressure is detected and the change rate of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to increase the frequency; the air conditioner has the advantages that the compressor is prevented from triggering the low-voltage protection to stop, the air conditioning effect is guaranteed, the problem that the compressor is frequently started and stopped is solved, the temperature control precision of the indoor unit is improved, and the reliability of the air conditioning unit is improved.
In some embodiments of the present application, the indoor unit is disposed inside the refrigerated display cabinet. When the evaporation pressure is reduced and the change rate of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to reduce the frequency; when the evaporation pressure rises and the change rate of the evaporation pressure is greater than the change rate threshold value, controlling the compressor to increase the frequency; the refrigeration effect of the refrigeration display cabinet is guaranteed, and the temperature control precision and reliability of the refrigeration display cabinet are improved.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions.
Claims (10)
1. The control method of the air conditioning unit comprises an outdoor unit and a plurality of indoor units, wherein each indoor unit is connected with the outdoor unit; the method is characterized in that: the control method comprises the following steps:
periodically detecting the evaporation pressure;
when the evaporation pressure is reduced and the change rate is greater than the change rate threshold value, controlling the compressor to reduce the frequency;
and when the evaporation pressure rises and the change rate is larger than the change rate threshold value, controlling the compressor to increase the frequency.
2. The air conditioning unit control method according to claim 1, characterized in that: when the compressor is controlled to reduce the frequency, the target running frequency N1 of the compressor is as follows:
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
3. The air conditioning unit control method according to claim 1, characterized in that: when the compressor is controlled to be in the frequency increasing state, the target operation frequency N2 of the compressor is as follows:
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
4. The air conditioning unit control method according to claim 1, characterized in that:
the change rate threshold value is a preset fixed value; or,
rate of change threshold = K3 × Ps 1;
wherein,
k3, correction factor;
ps1, the evaporation pressure change rate at which all indoor units are operated.
5. The air conditioning unit control method according to any one of claims 1 to 4, characterized in that:
when the compressor is controlled to reduce the frequency, the compressor is controlled to reduce the frequency at a second speed;
when the compressor is controlled to be subjected to frequency rising, the compressor is controlled to be subjected to frequency rising at a second speed;
wherein the second speed > the first speed;
the first speed is the compressor frequency increasing or reducing speed when all indoor units are operated.
6. The air conditioning unit control system comprises an outdoor unit and a plurality of indoor units, wherein each indoor unit is connected with the outdoor unit; the method is characterized in that: the control system includes:
the evaporation pressure detection module is used for periodically detecting the evaporation pressure;
the calculation module is used for calculating the change rate of the evaporation pressure;
a judgment module for
When the evaporation pressure is reduced and the change rate is greater than the change rate threshold value, controlling the compressor to reduce the frequency;
and when the evaporation pressure rises and the change rate is larger than the change rate threshold value, controlling the compressor to increase the frequency.
7. The air conditioning unit control system according to claim 6, wherein: the air conditioning unit control system further includes:
the target operating frequency calculation module is used for calculating a target operating frequency N1 when the compressor is used for reducing the frequency;
N1=k1*Nqyc*（Psqyc-Psdq）/Psqyc；
wherein,
k1, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
psdq which is an evaporation pressure detection value of the current detection period;
the method is also used for calculating a target running frequency N2 when the compressor is subjected to frequency rising;
N2=k2*Nqyc*Psdq/Psqyc；
wherein,
k2, correction factor;
nqyc, the compressor operating frequency of the last detection cycle;
psqyc, which is the evaporation pressure detection value of the last detection cycle;
and Psdq, which is the evaporation pressure detection value of the current detection period.
8. The air conditioning assembly control system of claim 6, wherein: the air conditioning unit control system further includes:
a rate of change threshold calculation module to calculate a rate of change threshold = K3 × Ps 1;
wherein,
k3, correction factor;
ps1, the evaporation pressure change rate at which all indoor units are operated.
9. An air conditioning unit, its characterized in that: the method comprises the following steps:
an outdoor unit;
a plurality of indoor units, each of which is connected with the outdoor unit;
a controller for performing the air conditioning unit control method as claimed in any one of claims 1 to 5.
10. Air conditioning assembly according to claim 9, characterized in that: the indoor unit is arranged in the refrigeration display cabinet.
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Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04190054A (en) * | 1990-11-26 | 1992-07-08 | Matsushita Refrig Co Ltd | Multi-chamber type air conditioner |
| JPH04214152A (en) * | 1990-12-13 | 1992-08-05 | Sanyo Electric Co Ltd | Controller for refrigerating cycle |
| CN1266975A (en) * | 1999-03-10 | 2000-09-20 | 株式会社日立制作所 | Refrigerating device |
| JP2001153475A (en) * | 1999-11-25 | 2001-06-08 | Hitachi Ltd | Refrigerating plant |
| CN101978227A (en) * | 2008-03-24 | 2011-02-16 | 大金工业株式会社 | Refrigeration apparatus |
| CN103486692A (en) * | 2013-09-17 | 2014-01-01 | 青岛海信日立空调***有限公司 | Load self-adaptation variable-frequency multi-connection heat pump system and method for controlling compressor frequency |
| KR20150026208A (en) * | 2013-09-02 | 2015-03-11 | 엘지전자 주식회사 | An air conditioner and a control method the same |
| CN106595158A (en) * | 2016-12-22 | 2017-04-26 | 重庆美的通用制冷设备有限公司 | Low-pressure control method, system and air conditioner for unit refrigeration system |
| CN108036559A (en) * | 2018-01-25 | 2018-05-15 | 天津商业大学 | Suitable for the control method and control device of full frequency-changeable compressor Parallel sets |
| CN108534309A (en) * | 2018-04-19 | 2018-09-14 | 广东美的暖通设备有限公司 | Air-conditioning system and its control method |
| CN109612021A (en) * | 2018-11-28 | 2019-04-12 | 宁波奥克斯电气股份有限公司 | A kind of multi-gang air conditioner abnormal sound control method and multi-gang air conditioner |
| CN110513930A (en) * | 2019-09-05 | 2019-11-29 | 四川长虹空调有限公司 | Net for air-source heat pump units frequency-changeable compressor adding and subtracting load control method |
| CN110651163A (en) * | 2018-04-26 | 2020-01-03 | 日立江森自控空调有限公司 | Air conditioner |
| CN111271836A (en) * | 2019-12-30 | 2020-06-12 | 宁波奥克斯电气股份有限公司 | Control method and device, air conditioner and computer readable storage medium |
| CN111692701A (en) * | 2020-06-09 | 2020-09-22 | 宁波奥克斯电气股份有限公司 | Air conditioner high-temperature sterilization control method and device, storage medium and air conditioner |
| CN112781290A (en) * | 2020-04-10 | 2021-05-11 | 青岛海尔新能源电器有限公司 | Heat pump system control method and heat pump system |
| WO2021223616A1 (en) * | 2020-06-23 | 2021-11-11 | 青岛海尔空调电子有限公司 | Compressor frequency control method for multi-split air-conditioning unit |
| CN113803843A (en) * | 2021-09-30 | 2021-12-17 | 珠海格力电器股份有限公司 | Multi-split refrigeration system control method and device, multi-split refrigeration system and air conditioner |
| CN114110911A (en) * | 2021-10-19 | 2022-03-01 | 宁波奥克斯电气股份有限公司 | Compressor frequency control method and air conditioner |
-
2022
- 2022-03-29 CN CN202210318897.7A patent/CN114739081A/en active Pending
Patent Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04190054A (en) * | 1990-11-26 | 1992-07-08 | Matsushita Refrig Co Ltd | Multi-chamber type air conditioner |
| JPH04214152A (en) * | 1990-12-13 | 1992-08-05 | Sanyo Electric Co Ltd | Controller for refrigerating cycle |
| CN1266975A (en) * | 1999-03-10 | 2000-09-20 | 株式会社日立制作所 | Refrigerating device |
| JP2001153475A (en) * | 1999-11-25 | 2001-06-08 | Hitachi Ltd | Refrigerating plant |
| CN101978227A (en) * | 2008-03-24 | 2011-02-16 | 大金工业株式会社 | Refrigeration apparatus |
| KR20150026208A (en) * | 2013-09-02 | 2015-03-11 | 엘지전자 주식회사 | An air conditioner and a control method the same |
| CN103486692A (en) * | 2013-09-17 | 2014-01-01 | 青岛海信日立空调***有限公司 | Load self-adaptation variable-frequency multi-connection heat pump system and method for controlling compressor frequency |
| CN106595158A (en) * | 2016-12-22 | 2017-04-26 | 重庆美的通用制冷设备有限公司 | Low-pressure control method, system and air conditioner for unit refrigeration system |
| CN108036559A (en) * | 2018-01-25 | 2018-05-15 | 天津商业大学 | Suitable for the control method and control device of full frequency-changeable compressor Parallel sets |
| CN108534309A (en) * | 2018-04-19 | 2018-09-14 | 广东美的暖通设备有限公司 | Air-conditioning system and its control method |
| CN110651163A (en) * | 2018-04-26 | 2020-01-03 | 日立江森自控空调有限公司 | Air conditioner |
| CN109612021A (en) * | 2018-11-28 | 2019-04-12 | 宁波奥克斯电气股份有限公司 | A kind of multi-gang air conditioner abnormal sound control method and multi-gang air conditioner |
| CN110513930A (en) * | 2019-09-05 | 2019-11-29 | 四川长虹空调有限公司 | Net for air-source heat pump units frequency-changeable compressor adding and subtracting load control method |
| CN111271836A (en) * | 2019-12-30 | 2020-06-12 | 宁波奥克斯电气股份有限公司 | Control method and device, air conditioner and computer readable storage medium |
| CN112781290A (en) * | 2020-04-10 | 2021-05-11 | 青岛海尔新能源电器有限公司 | Heat pump system control method and heat pump system |
| CN111692701A (en) * | 2020-06-09 | 2020-09-22 | 宁波奥克斯电气股份有限公司 | Air conditioner high-temperature sterilization control method and device, storage medium and air conditioner |
| WO2021223616A1 (en) * | 2020-06-23 | 2021-11-11 | 青岛海尔空调电子有限公司 | Compressor frequency control method for multi-split air-conditioning unit |
| CN113803843A (en) * | 2021-09-30 | 2021-12-17 | 珠海格力电器股份有限公司 | Multi-split refrigeration system control method and device, multi-split refrigeration system and air conditioner |
| CN114110911A (en) * | 2021-10-19 | 2022-03-01 | 宁波奥克斯电气股份有限公司 | Compressor frequency control method and air conditioner |
Non-Patent Citations (1)
| Title |
|---|
| 武连发;熊建国;余凯;罗亚军;: "高温多联机空调***的控制方式研究", 制冷技术, no. 04 * |
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