CN112629053B - Water chilling unit and air supplementing control method - Google Patents

Water chilling unit and air supplementing control method Download PDF

Info

Publication number
CN112629053B
CN112629053B CN202011562064.2A CN202011562064A CN112629053B CN 112629053 B CN112629053 B CN 112629053B CN 202011562064 A CN202011562064 A CN 202011562064A CN 112629053 B CN112629053 B CN 112629053B
Authority
CN
China
Prior art keywords
compressor
preset
opening
load
detected
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202011562064.2A
Other languages
Chinese (zh)
Other versions
CN112629053A (en
Inventor
任艳君
王锡元
吉磊
邵存东
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Original Assignee
Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qingdao Hisense Hitachi Air Conditioning System Co Ltd filed Critical Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority to CN202011562064.2A priority Critical patent/CN112629053B/en
Publication of CN112629053A publication Critical patent/CN112629053A/en
Application granted granted Critical
Publication of CN112629053B publication Critical patent/CN112629053B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/005—Compression machines, plants or systems with non-reversible cycle of the single unit type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Positive-Displacement Air Blowers (AREA)
  • Air Conditioning Control Device (AREA)

Abstract

The invention discloses a water chilling unit and an air supplementing control method, wherein a controller of the water chilling unit is configured to: if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening; if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor; the frequency load is the ratio of the operating frequency to the full load frequency of the compressor, so that the phenomenon that the liquid carrying of the economizer and the partial load air supply are not effective due to the fact that the traditional air supply is not regulated is avoided, the attenuation phenomenon of the air supply performance caused by controlling the air supply quantity of the plate type heat exchanger according to the air supply superheat degree is avoided, and the efficiency and the stability of the compressor are improved.

Description

Water chilling unit and air supplementing control method
Technical Field
The application relates to the field of water chilling unit control, in particular to a water chilling unit and an air supplementing control method.
Background
For the middle air supplementing control scheme with an economizer, most of the current research documents only give qualitative analysis of a volumetric compressor, only give influence analysis of air supplementing on unit performance under full-load working conditions, give qualitative conclusion of the existence of optimal air supplementing pressure and optimal air supplementing quantity, but do not give specific schemes of air supplementing control under full-load and partial-load working conditions for a speed type centrifugal machine, and the best middle pressure and middle temperature are calculated by adopting Pm= Pc×pe (Pm is middle pressure, pc is condensing pressure, and Pe is evaporating pressure) in some documents, but the optimal air supplementing pressure is continuously changed along with the working conditions and the change of the working phases in the actual operation process of the unit, and the unit cannot have optimal performance under all working conditions, especially has no due air supplementing effect during partial-load operation, and is not reasonable in air supplementing pressure selection and easy to cause adverse effects of air supplementing belt or performance reduction and the like.
In addition, at present, most manufacturers have a scheme that a valve is not added to a gas supplementing pipeline, and gas supplementing is not regulated at all in practical application, and in the initial starting process of the compressor, the normal operation pressure difference is not established, so that the gas supplementing opening is too large, the flash tank type economizer is easily filled with refrigerant due to instant negative pressure, the gas supplementing is carried with liquid, and the compressor is irreversibly damaged.
At present, a more air supplementing control scheme is applied in the magnetic suspension market, namely, an economizer adopts a plate heat exchanger, the air supplementing superheat degree of a refrigerant gaseous outlet of the plate heat exchanger is controlled to control the refrigerant liquid supply quantity entering the plate economizer, the scheme only aims at the liquid supply quantity entering the plate economizer, and not starts from the air supplementing quantity of a compressor, and the scheme adopts the air supplementing superheat degree for control, so that the air supplementing superheat degree is selected to be larger between 8 ℃ and 10 ℃, but according to the two-stage compression air supplementing enthalpy increasing principle, the larger the air supplementing superheat degree is, the worse the air supplementing effect on the compressor is, and the performance advantage of air supplementing on the compressor cannot be fully exerted.
Therefore, how to provide a water chiller capable of improving efficiency and stability of a compressor is a technical problem to be solved at present.
Disclosure of Invention
The invention provides a water chilling unit which is used for solving the technical problems of poor air supplementing effect and low stability of a water chilling unit in the prior art.
The water chiller includes:
the compressor is a double-stage centrifugal type and is used for compressing low-temperature low-pressure refrigerant gas into high-temperature high-pressure refrigerant gas and discharging the high-temperature high-pressure refrigerant gas to the condenser;
the condenser is used for condensing the high-temperature high-pressure refrigerant gas, reducing the pressure through the first throttle valve and then discharging the high-temperature high-pressure refrigerant gas to the economizer;
the economizer is a flash tank type and is used for carrying out gas-liquid separation on the refrigerant, the separated gas is converged with the low-pressure-stage exhaust of the compressor through a gas supplementing pipeline and then enters the high-pressure stage of the compressor, and the separated liquid is discharged to the evaporator through the second throttle valve;
the evaporator is used for evaporating the low-temperature low-pressure refrigerant to reduce the temperature of chilled water and sending the low-temperature low-pressure refrigerant gas into the compressor;
the air supplementing pipeline is provided with an air supplementing regulating valve, and a controller of the water chilling unit is configured to:
if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
In some embodiments of the present application, the controller is further configured to:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
In some embodiments of the present application, the controller is specifically configured to:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
In some embodiments of the present application, the controller is specifically configured to:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
In some embodiments of the present application, the controller is further configured to:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
Correspondingly, the invention also provides a method for controlling the air supplementing of the water chilling unit, which is applied to the water chilling unit comprising a compressor, a condenser, a first throttle valve, an economizer, a second throttle valve, an evaporator and a controller, wherein an air supplementing regulating valve is arranged on an air supplementing pipeline of the economizer, and the method comprises the following steps:
if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
In some embodiments of the present application, the method further comprises:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
In some embodiments of the present application, if a preset alarm signal of the compressor is detected or the compressor enters a preset steady state, the target opening is determined according to a frequency load of the compressor and a vane opening of the compressor, which specifically is:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
In some embodiments of the present application, if a shutdown instruction is detected, the target opening is controlled according to the frequency load, and the compressor is stopped, specifically:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
In some embodiments of the present application, the method further comprises:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a water chilling unit and an air supplementing control method, wherein a controller of the water chilling unit is configured to: if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening; if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor; the frequency load is the ratio of the operating frequency to the full load frequency of the compressor, so that the phenomenon that the liquid carrying of the economizer and the partial load air supply are not effective due to the fact that the traditional air supply is not regulated is avoided, the attenuation phenomenon of the air supply performance caused by controlling the air supply quantity of the plate type heat exchanger according to the air supply superheat degree is avoided, and the efficiency and the stability of the compressor are improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 shows a schematic diagram of a refrigeration cycle of a water chiller according to an embodiment of the present invention;
fig. 2 shows a refrigeration cycle pressure enthalpy diagram in an embodiment of the invention;
FIG. 3 shows a schematic flow chart of a method for controlling air make-up of a chiller according to an embodiment of the present invention
Fig. 4 is a schematic flow chart of a method for controlling air make-up of a water chiller according to another embodiment of the present invention.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.
In the description of the present application, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.
The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.
In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.
The embodiment of the invention provides a water chilling unit, as shown in fig. 1, which comprises a refrigerant circulation loop consisting of a compressor 100, a condenser 200, a first throttle valve 300, an economizer 400, a second throttle valve 600 and an evaporator 700, wherein the compressor 100 is a magnetic suspension double-stage centrifugal compressor, the economizer 400 is a flash tank type economizer, a gas supplementing pipeline is connected with a gaseous outlet of a refrigerant at the top of the economizer 400 and a gas supplementing port in the middle of the compressor 100, and the gas supplementing pipeline is provided with a gas supplementing regulating valve 500 for gas supplementing regulation.
During refrigeration, the low-pressure refrigerant vapor (state point 1) of the evaporator 700, the low-pressure stage compression of the compressor 100 to the intermediate pressure (state point 2), the merging of the medium-pressure gas separated in the economizer 400, the high-pressure stage compression of the compressor 100 to the condensing pressure (state point 4), the condensation of the high-pressure liquid (state point 5) in the condenser 200, the first-stage throttling to the intermediate pressure (state point 6), the gas-liquid separation in the economizer 400, the merging of the saturated gas separated in the economizer 400 as the intermediate make-up gas and the low-pressure stage exhaust gas (state point 2) of the compressor 100 (state point 3) to the high-pressure stage compression, the separated liquid (state point 8) passing through the second-stage throttling to the evaporating pressure (state point 9), the evaporation refrigeration of the evaporator 700, and the low-pressure vapor (state point 1) of the refrigerant entering the low-pressure stage compression of the compressor 100, thus completing one refrigeration cycle.
The evaporator 700 of the present embodiment is further connected to a user side, and after the temperature of the chilled water in the evaporator 700 is reduced, the chilled water enters the user side, and the chilled water in the evaporator 700 can be replenished by the user side.
As shown in fig. 2, the gas separated by the flash tank type economizer is not compressed by the low-pressure stage, but directly enters the high-pressure stage for compression as the middle air supplementing, so that the work consumption of the low-pressure stage is reduced, the refrigerating capacity per unit volume of the refrigerant is improved, and the improved refrigerating capacity is the enthalpy difference (h 9-h 6) between the state point 9 and the state point 6, so that the energy efficiency of the unit is greatly improved. Therefore, the reasonable air supplementing control scheme has important significance for the magnetic suspension double-stage compression centrifugal unit.
The invention reasonably controls the air supplementing quantity, namely the adjustment of the EMV opening of the air supplementing regulating valve, in the high-pressure stage compression process after the saturated gas (state point 7) separated from the economizer is used as the intermediate air supplementing and the low-pressure stage exhaust (state point 2) of the compressor are converged (state point 3), so that the reasonable liquid level of the economizer and the evaporator under various working conditions is ensured, and the stable and efficient operation of the unit under various working conditions is ensured.
The controller of the water chiller is configured to:
if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
In this embodiment, if a compressor start command is detected, the compressor is started, and the compressor enters a start stage, at this time, because the compressor is in a loading process and is not fully loaded in the start stage, the running state of the unit is unstable, and at this time, if the air supply regulating valve is regulated according to load or frequency, the frequent action of the valve can exist to cause unstable liquid level of the economizer and fluctuation of current of the unit, which is easy to cause failure and shutdown alarm of the unit; if the air-supplementing regulating valve is fully opened at the stage, the pressure ratio is not established in the starting process, and the full opening of the air-supplementing regulating valve is easy to cause pressure reduction in the economizer to cause air-supplementing carrying liquid, so that unit fault alarm is easy to cause and damage is caused to the compressor, and therefore, the target opening of the air-supplementing regulating valve is determined based on the preset initial opening, and the air-supplementing regulating valve is maintained at the preset initial opening. The preset initial opening can be reasonably set through experiments according to the selected valve type and the size of the configured air supplementing pipeline.
The compressor comprises guide vanes, the opening of the guide vanes can be adjusted along with the load of the compressor, the frequency of the compressor can be adjusted along with the load, if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, the air supplementing regulating valve is led to exit from a preset initial opening, the target opening of the air supplementing regulating valve is determined according to the frequency load of the compressor and the opening of the guide vanes of the compressor, and the frequency load is the ratio of the running frequency of the compressor to the full load frequency.
The preset alarm signal can be low suction pressure early warning, low exhaust superheat degree early warning, or high exhaust pressure early warning, if the alarm is detected, the load limiting or the preset operation corresponding to the alarm is adopted to reduce the shutdown times in addition to controlling the air supplementing regulating valve, the state of the unit is adjusted in advance, and the unit is prevented from directly achieving the function of fault shutdown.
To further improve the stability of the chiller, in some embodiments of the present application, the controller is further configured to:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
In the embodiment, because the compressor is in the unloading process in the stopping process, if the air supplementing regulating valve is fully closed in the unloading process, the liquid level of the economizer and the evaporator is lower in the stopping stage, and the low evaporation pressure fault is caused; if the air-supplementing regulating valve is fully opened, the air-supplementing regulating valve is easy to cause damage to the compressor due to the fact that the air-supplementing regulating valve is too large in opening degree in the unloading process of the compressor, so that the target opening degree of the air-supplementing regulating valve is controlled according to the frequency load, and the compressor is stopped.
In order to determine an accurate target opening upon detection of a preset alert signal of the compressor or a preset steady state of the compressor, in a preferred embodiment of the present application, the controller is specifically configured to:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
In this embodiment, the opening of the air-supplementing adjusting valve needs to be adjusted according to the actual running Load of the compressor, the actual running Load of the compressor is related to the opening IGV of the guide vane and the running frequency in the running process of the compressor, and the compressor running frequency Load P can be compared with the actual running Load of the compressor linearly at a constant time of the opening IGV of the guide vane according to the fact that the flow of the centrifugal compressor is in direct proportion to the rotational speed, that is, the frequency. However, when the operating frequency of the compressor is fixed, the vane opening IGV of the compressor is in nonlinear correspondence with the actual operating Load of the compressor, a corresponding relation curve of the vane opening and the compressor Load can be obtained with a manufacturer of the compressor, or a corresponding relation between the vane opening IGV of the compressor and the actual operating Load of the compressor can be obtained through test verification under the condition that the compressor frequency is fixed, the compressor frequency can be fixed at 100% of full-Load frequency, different vane openings are selected, the actual corresponding relation between the vane opening and the compressor Load is obtained under the same operating condition, and test data are fitted into a relation equation of the vane opening IGV and the actual operating Load of the compressor:
Load＝a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e (1)
and (3) synthesizing the relation between the frequency and the opening of the guide vane and the actual load of the compressor to obtain the actual running load of the magnetic suspension compressor as follows:
Load＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P (2)
according to the set flow characteristic curve of the air-supplementing regulating valve, the corresponding relation between the target opening EMV of the air-supplementing regulating valve and the actual running Load of the compressor is obtained, and according to the scheme, the flow characteristic curve of the air-supplementing regulating valve can be approximated to be that the flow linearly corresponds to the opening of the valve, and then the target opening EMV of the air-supplementing regulating valve can linearly correspond to the actual running Load of the compressor, so that the target opening control equation of the air-supplementing regulating valve is obtained:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P (3)
it should be noted that, the solution of the above preferred embodiment is only one specific implementation solution proposed in the present application, and other ways of determining the target opening according to the frequency load of the compressor and the opening of the guide vane are all within the protection scope of the present application.
In order to determine an accurate target opening during a shutdown, in a preferred embodiment of the present application, the controller is specifically configured to:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
In this embodiment, during the shutdown process of the unit, the opening of the air-supplementing adjusting valve may linearly correspond to the compressor frequency load P, and the compressor minimum frequency load P 0 When the compressor is in the maximum frequency load Pmax, the air supplementing regulating valve can be opened to the maximum EMVmax; compressor frequency load at P 0 When P is less than Pmax, the valve opening linearly corresponds to the compressor frequency, and an equation is obtained:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin (4)
it should be noted that the frequency adjustment period of the compressor and the opening adjustment period of the air-supplementing adjustment valve are controlled within a reasonable preset range respectively. Namely, the frequency adjustment period of the compressor is in a first preset range and the opening adjustment period of the air supplementing adjusting valve is in a second preset range.
It should be noted that, the solution of the above preferred embodiment is only one specific implementation solution proposed in the present application, and other ways of controlling the target opening according to the frequency load are all within the protection scope of the present application.
To further improve the stability of the chiller, in some embodiments of the present application, the controller is further configured to:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
In this embodiment, the preset minimum opening is smaller than the preset initial opening, and after the compressor is completely stopped, the opening of the air-supplementing regulating valve is reduced to the preset minimum opening, so that the next start of the compressor is facilitated.
By applying the above technical solution, the controller of the water chiller is configured to: if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening; if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor; the frequency load is the ratio of the operating frequency to the full load frequency of the compressor, so that the phenomenon that the liquid carrying of the economizer and the partial load air supply are not effective due to the fact that the traditional air supply is not regulated is avoided, the attenuation phenomenon of the air supply performance caused by controlling the air supply quantity of the plate type heat exchanger according to the air supply superheat degree is avoided, and the efficiency and the stability of the compressor are improved.
In order to further explain the technical idea of the invention, the technical scheme of the invention is described with specific application scenarios.
The embodiment of the invention provides a method for controlling air supplementing of a water chilling unit, which is applied to the water chilling unit comprising a compressor, a condenser, a first throttle valve, an economizer, a second throttle valve, an evaporator and a controller, wherein an air supplementing regulating valve is arranged on an air supplementing pipeline of the economizer, as shown in fig. 3, and the method comprises the following steps:
step S301, emv=emvmin.
Before the compressor is started, the target opening EMV of the air-supplementing regulating valve is a preset minimum opening EMVmin.
Step S302, if there is a start of the compressor, step S303 is executed, otherwise step S301 is executed.
Step S303, emv=emvi, and step S304 and step S305 are performed.
In the starting process of the compressor, the target opening degree EMV of the air supplementing regulating valve is a preset initial opening degree EMVi.
Step S304, if a preset alarm exists, step S306 is executed, otherwise step S303 is executed.
Step S305 is executed if the load is to be in the steady state, if yes, step S306 is executed, otherwise step S303 is executed.
Step S306, emv= (a×igv) 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P。
And determining the target opening EMV of the air supplementing regulating valve according to the guide vane opening IGV and the frequency load P of the compressor.
Step S307, if a shutdown command is received, step S308 is executed, otherwise step S306 is executed.
Step S308, EMV= (P-P) 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin。
And determining the target opening EMV of the air supplementing regulating valve according to the frequency load P of the compressor.
Step S309, if the compressor is completely stopped, step S310 is executed, otherwise step S308 is executed.
Step S310, emv=emvmin.
And adjusting the target opening EMV of the air supplementing regulating valve to a preset minimum opening EMVmin.
Corresponding to the water chilling unit in the embodiment of the present application, the embodiment of the present application further provides a method for controlling air supply of the water chilling unit, which is applied to a water chilling unit including a compressor, a condenser, a first throttle valve, an economizer, a second throttle valve, an evaporator and a controller, wherein an air supply pipe of the economizer is provided with an air supply regulating valve, as shown in fig. 4, and the method includes:
step S401, if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
step S402, if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
In order to determine an accurate target opening when detecting a preset alarm signal of the compressor or the compressor entering a preset steady state, in a preferred embodiment of the present application, if detecting the preset alarm signal of the compressor or the compressor entering the preset steady state, determining the target opening according to a frequency load of the compressor and a vane opening of the compressor specifically includes:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
In order to further improve stability of the water chiller, in some embodiments of the present application, the method further includes:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
In order to determine an accurate target opening degree during a shutdown process, in a preferred embodiment of the present application, if a shutdown command is detected, the target opening degree is controlled according to the frequency load, and the compressor is stopped, specifically:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
In order to improve the stability of the water chiller, in some embodiments of the present application, the method further includes:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting thereof; although the present application has been described in detail with reference to the foregoing embodiments, one of ordinary skill in the art will appreciate that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not drive the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims (10)

1. A chiller, comprising:
the compressor is a double-stage centrifugal type and is used for compressing low-temperature low-pressure refrigerant gas into high-temperature high-pressure refrigerant gas and discharging the high-temperature high-pressure refrigerant gas to the condenser;
the condenser is used for condensing the high-temperature high-pressure refrigerant gas, reducing the pressure through the first throttle valve and then discharging the high-temperature high-pressure refrigerant gas to the economizer;
the economizer is a flash tank type and is used for carrying out gas-liquid separation on the refrigerant, the separated gas is converged with the low-pressure-stage exhaust of the compressor through a gas supplementing pipeline and then enters the high-pressure stage of the compressor, and the separated liquid is discharged to the evaporator through a second throttle valve;
the evaporator is used for evaporating the low-temperature low-pressure refrigerant to reduce the temperature of chilled water and sending the low-temperature low-pressure refrigerant gas into the compressor;
the utility model is characterized in that, be provided with the air make-up governing valve on the air make-up pipeline, the controller of cooling water set is configured as:
if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
2. The chiller according to claim 1 wherein the controller is further configured to:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
3. The chiller according to claim 1 wherein the controller is specifically configured to:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
4. The chiller according to claim 2 wherein the controller is specifically configured to:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
5. The chiller according to claim 4 wherein the controller is further configured to:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
6. The utility model provides a make-up air control method of cooling water set, is applied to including compressor, condenser, first choke valve, economizer, second choke valve, evaporimeter and the cooling water set of controller, its characterized in that, be provided with the make-up air governing valve on the make-up air pipeline of this economizer, the method includes:
if a compressor starting instruction is detected, starting the compressor and determining a target opening of the air supplementing regulating valve based on a preset initial opening;
if a preset alarm signal of the compressor or the compressor enters a preset stable state is detected, determining the target opening according to the frequency load of the compressor and the opening of the guide vane of the compressor;
wherein the frequency load is the ratio of the operating frequency of the compressor to the full load frequency.
7. The method of claim 6, wherein the method further comprises:
and if a shutdown instruction is detected, controlling the target opening according to the frequency load, and stopping the compressor.
8. The method according to claim 6, wherein if a preset alert signal of the compressor or the compressor entering a preset steady state is detected, determining the target opening according to a frequency load of the compressor and a vane opening of the compressor is specifically:
if a preset alarm signal of the compressor is detected or the compressor enters a preset stable state, determining the target opening according to a formula I, wherein the formula I specifically comprises:
EMV＝(a×IGV 4 +b×IGV 3 +c×IGV 2 +d×IGV+e)×P
wherein EMV is the target opening degree, IGV is the guide vane opening degree, P is the frequency load, and a, b, c, d and e are preset constants.
9. The method of claim 7, wherein if a shutdown command is detected, controlling the target opening according to the frequency load and stopping the compressor, in particular:
if the shutdown instruction is detected and the frequency load is a preset maximum load, determining the target opening based on the preset maximum opening, and stopping the compressor;
if the shutdown instruction is detected and the frequency load is a preset minimum load, determining the target opening based on the preset minimum opening, and stopping the compressor;
if the shutdown instruction is detected, and the frequency load is smaller than the preset maximum load and larger than the preset minimum load, determining the target opening based on a formula II, and stopping the compressor, wherein the formula II specifically comprises:
EMV＝(P-P 0 )×(EMVmax-EMVmin)/(Pmax-P 0 )+EMVmin
wherein EMV is the target opening degree, P is the frequency load, P 0 For the preset minimum load, pmax is the preset maximum load, EMVmax is the preset maximum opening, and EMVmin is the preset minimum opening.
10. The method of claim 9, wherein the method further comprises:
and if the compressor is detected to stop and the opening of the air supplementing regulating valve is not the preset minimum opening, closing the opening of the air supplementing regulating valve to the preset minimum opening.
CN202011562064.2A 2020-12-25 2020-12-25 Water chilling unit and air supplementing control method Active CN112629053B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011562064.2A CN112629053B (en) 2020-12-25 2020-12-25 Water chilling unit and air supplementing control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011562064.2A CN112629053B (en) 2020-12-25 2020-12-25 Water chilling unit and air supplementing control method

Publications (2)

Publication Number Publication Date
CN112629053A CN112629053A (en) 2021-04-09
CN112629053B true CN112629053B (en) 2023-06-13

Family

ID=75324876

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011562064.2A Active CN112629053B (en) 2020-12-25 2020-12-25 Water chilling unit and air supplementing control method

Country Status (1)

Country Link
CN (1) CN112629053B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113983653B (en) * 2021-10-21 2022-12-09 珠海格力节能环保制冷技术研究中心有限公司 Air conditioning unit starting control method, device and system and air conditioning unit
CN114198927B (en) * 2021-11-19 2023-09-26 青岛海尔空调电子有限公司 Method, device, equipment and medium for detecting load rate of compressor of water chilling unit

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004116931A (en) * 2002-09-27 2004-04-15 Tokyo Gas Co Ltd Gas heat pump type refrigeration device and its control method
JP2013174237A (en) * 2012-01-23 2013-09-05 Osaka Gas Co Ltd Exhaust turbine type supercharged engine and its load applying method
CN108131871A (en) * 2017-12-01 2018-06-08 重庆美的通用制冷设备有限公司 The control method of variable frequency centrifuge and hot gas bypass valve therein
CN110513903A (en) * 2019-08-14 2019-11-29 青岛海信日立空调系统有限公司 A kind of control method of cooling cycle system
CN110940123A (en) * 2019-11-29 2020-03-31 广东海悟科技有限公司 Air supplementing port normally-open type variable frequency compressor air supplementing and enthalpy increasing system, control method thereof and computer readable storage medium
CN112178965A (en) * 2020-09-18 2021-01-05 珠海格力电器股份有限公司 Water chilling unit and air supplementing adjusting method thereof
CN114165955A (en) * 2021-11-26 2022-03-11 珠海格力节能环保制冷技术研究中心有限公司 Refrigerating unit control processing method and device, refrigerating unit and storage medium

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180031282A1 (en) * 2016-07-26 2018-02-01 Lg Electronics Inc. Supercritical refrigeration cycle apparatus and method for controlling supercritical refrigeration cycle apparatus
EP3798534B1 (en) * 2019-09-30 2023-06-07 Daikin Industries, Ltd. A heat pump

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004116931A (en) * 2002-09-27 2004-04-15 Tokyo Gas Co Ltd Gas heat pump type refrigeration device and its control method
JP2013174237A (en) * 2012-01-23 2013-09-05 Osaka Gas Co Ltd Exhaust turbine type supercharged engine and its load applying method
CN108131871A (en) * 2017-12-01 2018-06-08 重庆美的通用制冷设备有限公司 The control method of variable frequency centrifuge and hot gas bypass valve therein
CN110513903A (en) * 2019-08-14 2019-11-29 青岛海信日立空调系统有限公司 A kind of control method of cooling cycle system
CN110940123A (en) * 2019-11-29 2020-03-31 广东海悟科技有限公司 Air supplementing port normally-open type variable frequency compressor air supplementing and enthalpy increasing system, control method thereof and computer readable storage medium
CN112178965A (en) * 2020-09-18 2021-01-05 珠海格力电器股份有限公司 Water chilling unit and air supplementing adjusting method thereof
CN114165955A (en) * 2021-11-26 2022-03-11 珠海格力节能环保制冷技术研究中心有限公司 Refrigerating unit control processing method and device, refrigerating unit and storage medium

Also Published As

Publication number Publication date
CN112629053A (en) 2021-04-09

Similar Documents

Publication Publication Date Title
CN112629053B (en) Water chilling unit and air supplementing control method
KR20150070894A (en) Control method for air conditioner
CN107289681B (en) A kind of water cooler control method of refrigerant flow
CN103216963A (en) Air conditioner and starting control method thereof
WO2022012568A1 (en) Control method for compressor, control device, and heat exchange system
JP4737892B2 (en) Heat pump type water heater
CN112178965B (en) Qi tonifying regulation method
CN113513852B (en) Cooling system, refrigeration equipment and cooling method
CN112113364A (en) Water chilling unit and control method
CN206609075U (en) A kind of heat pump spray enthalpy system and air conditioner
CN112747489B (en) Multi-machine-head water chilling unit and control method
JP3996321B2 (en) Air conditioner and its control method
CN214333088U (en) Multi-channel energy-saving type refrigeration heating temperature control system
CN112594792A (en) Outdoor unit of air conditioner
CN115143612A (en) Control method and control device of heat pump system, heat pump system and air conditioner
EP3594587B1 (en) Heat pump hot water supply device
JP7080801B2 (en) Centrifugal chiller
JP4301546B2 (en) Refrigeration equipment
KR20210094213A (en) An air conditioning apparatus
CN114508808B (en) Magnetic suspension variable frequency water chilling unit
CN112361685B (en) Two-stage compressor control method, two-stage compressor refrigeration system and refrigeration equipment
KR20140093449A (en) An air conditioner and a control method the same
CN217979374U (en) Enhanced vapor injection control system of electronic expansion valve
CN219392531U (en) Temperature control device of temperature verification box
CN217686110U (en) Evaporation type low-temperature refrigerating unit device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant