CN110500822B - Control method of variable frequency air conditioner - Google Patents

Control method of variable frequency air conditioner Download PDF

Info

Publication number
CN110500822B
CN110500822B CN201910636763.8A CN201910636763A CN110500822B CN 110500822 B CN110500822 B CN 110500822B CN 201910636763 A CN201910636763 A CN 201910636763A CN 110500822 B CN110500822 B CN 110500822B
Authority
CN
China
Prior art keywords
frequency
heat exchange
pump
variable frequency
mode
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
CN201910636763.8A
Other languages
Chinese (zh)
Other versions
CN110500822A (en
Inventor
汪亚东
张龙
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 Haier Air Conditioner Gen Corp Ltd
Haier Smart Home Co Ltd
Original Assignee
Qingdao Haier Air Conditioner Gen Corp Ltd
Haier Smart Home 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 Haier Air Conditioner Gen Corp Ltd, Haier Smart Home Co Ltd filed Critical Qingdao Haier Air Conditioner Gen Corp Ltd
Priority to CN201910636763.8A priority Critical patent/CN110500822B/en
Publication of CN110500822A publication Critical patent/CN110500822A/en
Application granted granted Critical
Publication of CN110500822B publication Critical patent/CN110500822B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00Fluid-circulation arrangements
    • F25B41/20Disposition of valves, e.g. of on-off valves or flow control valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00Fluid-circulation arrangements
    • F25B41/30Expansion means; Dispositions thereof
    • F25B41/31Expansion valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00Arrangement or mounting of control or safety devices
    • F25B49/02Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022Compressor control arrangements
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00Control issues
    • F25B2600/02Compressor control
    • F25B2600/021Inverters therefor
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

The invention belongs to the technical field of air conditioners, and particularly relates to a control method of a variable frequency air conditioner. The invention aims to solve the problem that the existing air conditioning system with the waste heat recovery function is poor in energy-saving effect. For this purpose, the control method of the inverter air conditioner can determine the frequency mode of the inverter pump according to different branch circuit operation conditions, so that the energy-saving effect of the air conditioner is improved on the basis of meeting the basic operation requirement and the hot water heating requirement of the air conditioner and realizing waste heat recovery through the inverter operation of the inverter pump. Moreover, the control method of the invention can also determine whether the frequency conversion pump needs to reduce the frequency according to the current frequency mode of the frequency conversion pump and the opening degree change condition of the electronic expansion valve, and execute corresponding frequency reduction schemes aiming at different frequency modes of the frequency conversion pump under the condition that the frequency conversion pump needs to reduce the frequency, thereby optimizing and improving the energy-saving effect of the air conditioner again.

Description

Control method of variable frequency air conditioner
Technical Field
The invention belongs to the technical field of air conditioners, and particularly relates to a control method of a variable frequency air conditioner.
Background
Because the summer day is hot, the water consumption of people will be increased correspondingly, the urban water and electricity supply will be increased, and because the temperature requirement of the summer water is not very high, in the energy shortage era, if the waste heat generated by the air conditioner is used for heating the domestic water to meet the daily requirement of people, the consumption of the hot water on energy sources such as gas and the like can be avoided, and certain contribution is made to the improvement of the global greenhouse effect.
An air conditioning system is now provided. Compared with the existing air conditioner, the air conditioning system comprises a circulating heat exchange water path which can absorb waste heat of the air conditioner and heat hot water and a non-circulating heat exchange water path which is provided with a water inlet end and a water outlet end, so that the two water paths can be switched to exchange heat according to the heating requirement of the hot water. Because the flow demands of the water in the two heat exchange water paths are different, if a fixed-frequency pump is arranged to meet the water transportation demands of the two heat exchange water paths, unnecessary waste of energy sources can be caused. In view of the above problem, a control method better matched with the overall heat exchange water path of the air conditioning system is provided, so as to further improve the energy saving effect of the air conditioning system.
Disclosure of Invention
In order to solve the above problems in the prior art, that is, to solve the problem of poor energy saving effect of the air conditioning system with waste heat recovery function, the present invention provides a control method of a variable frequency air conditioner, the variable frequency air conditioner includes a compressor, an electronic expansion valve, an evaporator, a condenser and a heat exchange water path, the compressor, the electronic expansion valve, the evaporator and the condenser form a closed-loop refrigerant circulation system, the heat exchange water path includes a first heat exchange branch, a second heat exchange branch, a variable frequency pump and a valve assembly, a water storage device is disposed on the first heat exchange branch, a water supply device and a water discharge device are disposed on the second heat exchange branch, any one of the first heat exchange branch and the heat exchange branch can be communicated with the variable frequency pump, and the condenser dissipates heat through water flowing in the first heat exchange branch or the second heat exchange branch, the valve assembly can enable the heat exchange waterway to be switched between the first heat exchange branch and the second heat exchange branch, the variable frequency pump controls the flow state of water in the first heat exchange branch or the second heat exchange branch, and the control method comprises the following steps: acquiring a frequency mode of the variable frequency pump; acquiring the opening change condition of the electronic expansion valve; and selectively operating the variable frequency pump in a corresponding frequency reduction mode according to the frequency mode of the variable frequency pump and the opening change condition of the electronic expansion valve.
In a preferred embodiment of the above control method, the step of selectively operating the inverter pump in a corresponding down-conversion mode according to a frequency mode of the inverter pump and a change of an opening degree of the electronic expansion valve includes: and if the variable frequency pump is in the high-frequency mode and is in the frequency-increasing operation at the first frequency-increasing rate and the opening degree of the electronic expansion valve is reduced, reducing the variable frequency pump to a first set frequency and then in the frequency-increasing operation at the second frequency-increasing rate, wherein the first frequency-increasing rate is greater than the second frequency-increasing rate.
In a preferred technical solution of the above control method, the step of "reducing the variable frequency pump to a first set frequency and then performing the frequency-up operation at a second frequency-up rate" includes: and after the variable frequency pump operates at the current working frequency for a first preset time, the variable frequency pump is reduced to a first set frequency and then operates at a second frequency increasing rate in a frequency increasing mode.
In a preferred embodiment of the above control method, the step of selectively operating the inverter pump in a corresponding down-conversion mode according to a frequency mode of the inverter pump and a change of an opening degree of the electronic expansion valve further includes: and if the variable frequency pump operates in the low-frequency mode and the opening degree of the electronic expansion valve is reduced, reducing the variable frequency pump to a second set frequency for operation.
In a preferred embodiment of the above control method, the step of "operating the inverter pump at the second set frequency" includes: and reducing the frequency of the variable frequency pump to a second set frequency for operation after the variable frequency pump operates at the current working frequency for a second preset time.
In a preferred embodiment of the above control method, before the step of "obtaining the frequency mode of the inverter pump", the control method further includes: under the condition that the variable frequency pump starts to operate, valve opening and closing information of the valve assembly is obtained; determining the current branch operation condition of the heat exchange water channel according to the valve opening and closing information; the step of obtaining the frequency mode of the variable frequency pump comprises the following steps: and determining the frequency mode of the variable frequency pump according to the current branch circuit running condition.
In a preferred technical solution of the above control method, the step of "determining the frequency mode of the variable frequency pump according to the current branch operating condition" includes: if the heat exchange water path runs by the first heat exchange branch, acquiring the temperature parameter of water in the first heat exchange branch; and if the temperature parameter is increased and the increased temperature parameter is less than the set temperature, enabling the variable frequency pump to be operated in the high frequency mode at a first frequency increasing rate.
In a preferred technical solution of the above control method, in a case where the variable frequency pump is operated in an up-conversion mode in a high frequency mode, the control method further includes: and if the variable frequency pump is increased to the maximum working frequency, the heat exchange water route is switched to the second heat exchange branch from the first heat exchange branch, and meanwhile, the variable frequency pump is switched to the low-frequency mode from the high-frequency mode to operate.
In a preferred technical solution of the above control method, the step of "determining the frequency mode of the variable frequency pump according to the current branch operating condition" includes: and if the temperature parameter of the water in the first heat exchange water channel is equal to a set temperature, switching the heat exchange water channel from the first heat exchange branch to the second heat exchange branch, and simultaneously operating the variable frequency pump in a low frequency mode.
In a preferred technical solution of the above control method, the step of "determining the operating frequency of the variable frequency pump according to the current branch operating condition" includes: and if the heat exchange water path runs through the second heat exchange branch, the variable frequency pump is operated in a low frequency mode.
The technical personnel in the field can understand that the control method of the inverter air conditioner can determine whether the inverter pump needs to reduce the frequency according to the current frequency mode of the inverter pump and the opening degree change condition of the electronic expansion valve, and execute corresponding frequency reduction schemes aiming at different frequency modes of the inverter pump under the condition that the inverter pump needs to reduce the frequency, so that the energy consumption of the inverter pump is reduced as much as possible on the basis of meeting the basic operation requirement of the inverter air conditioner and not influencing the normal heat exchange of a condenser of the inverter air conditioner, and the energy-saving effect of the air conditioner can be further improved while the waste heat recovery of the air conditioner is realized.
Drawings
Preferred embodiments of the present invention are described below with reference to the accompanying drawings. The attached drawings are as follows:
FIG. 1 is a flow chart illustrating the main steps of a control method of an inverter air conditioner according to the present invention;
FIG. 2 is a first operation graph of a control method of an inverter air conditioner of the present invention;
fig. 3 is a first operation graph of the control method of the inverter air conditioner of the present invention.
Detailed Description
It will be appreciated by those skilled in the art that in the description of the invention, although the steps of the control method of the invention are described in a particular order in the present application, the order is not limiting and that the steps may be performed in a different order by those skilled in the art without departing from the basic principles of the invention.
Based on the problem that the energy-saving effect of an air conditioning system with a waste heat recovery function is poor, the invention provides a control method of a variable frequency air conditioner, and aims to further improve the energy-saving effect of the air conditioner on the basis of realizing waste heat recovery of the air conditioner.
In the technical scheme of the invention, the invention provides a variable frequency air conditioner which comprises a compressor, an electronic expansion valve, an evaporator, a condenser and a heat exchange water path. The compressor, the electronic expansion valve, the evaporator and the condenser form a closed-loop refrigerant circulating system. The variable frequency air conditioner is provided with an air supply device at the position of the evaporator so as to convey cold air generated after heat exchange of the evaporator to the indoor. The heat exchange water path specifically comprises a first heat exchange branch, a second heat exchange branch, a variable frequency pump and a valve assembly, wherein a water storage device is arranged on the first heat exchange branch, a water supply device and a water drainage device are arranged on the second heat exchange branch, and any one of the first heat exchange branch and the heat exchange branch can be communicated with the variable frequency pump. At least a portion of the first heat exchange branch and the second heat exchange branch flow through the condenser so that the condenser can dissipate heat through water flowing in the first heat exchange branch or the second heat exchange branch. The valve component comprises a plurality of switch valves respectively arranged on the first heat exchange branch and the second heat exchange branch, and the control module of the variable frequency air conditioner can control the switch valves to be opened or closed, so that a working water path of the heat exchange water path is switched between the first heat exchange branch and the second heat exchange branch in a mode of opening/closing part of the switch valves, and the branch for heat exchange of the condenser is switched. The variable frequency pump can control the flowing state of water in the first heat exchange branch or the second heat exchange branch, promote the water to flow in the first heat exchange branch or the second heat exchange branch, and regulate and control the flow of the water in the first/second heat exchange branch.
According to the system structure of the variable frequency air conditioner, the condenser of the variable frequency air conditioner can exchange heat through water flowing in the first heat exchange branch or the second heat exchange branch. And when this condenser carries out the heat transfer through first heat transfer branch road, the water circulation in this heat transfer branch road flows to utilize the heat that the condenser released to heat water to certain temperature after the storage to water storage device, supply the user to take. When the condenser exchanges heat through the second heat exchange branch, water in the branch exchanges heat with the condenser and then is discharged. Because the flow paths of the water of the two heat exchange branches are different, the temperature of the water which exchanges heat with the condenser in the first heat exchange branch gradually rises, the temperature difference with the condenser gradually decreases, and the temperature of the water which exchanges heat with the condenser in the second heat exchange branch is the temperature of the supplied water which is basically constant. In view of this, the frequency mode of inverter pump operation is different to the heat transfer condition of the branch road that the heat transfer water route is different.
The preferred embodiments of the present invention will be described below in conjunction with the inverter air conditioner described above.
Referring to fig. 1, fig. 1 is a flow chart illustrating major steps of a control method of an inverter air conditioner according to the present invention. As shown in fig. 1, the control method of the present invention includes:
step S1: acquiring a frequency mode of the variable frequency pump;
step S2: acquiring the opening change condition of the electronic expansion valve;
step S3: and selectively operating the variable frequency pump in a corresponding frequency reduction mode according to the frequency mode of the variable frequency pump and the opening degree change condition of the electronic expansion valve.
In step S1, the frequency mode of the variable frequency pump specifically refers to an operation mode of the variable frequency pump in different frequency ranges. For example, the frequency-variable pump is divided into a high frequency range, and the mode in which the frequency-variable pump operates at a frequency in the high frequency range is the high frequency mode. Similarly, the frequency modes may also include low frequency modes. In this step, the specific manner of acquiring the frequency pattern is not limited. For example, the frequency mode may be obtained by actively detecting and obtaining by the control unit of the general inverter air conditioner, or may be information representing the frequency mode automatically generated and stored by the control unit associated with the inverter air conditioner when the inverter air conditioner determines the frequency mode of the inverter pump, and the information representing the current frequency mode may be directly retrieved when needed.
In step S2, the change in the opening degree of the electronic expansion valve is specifically a case where the opening degree of the electronic expansion valve increases or decreases. Similarly, the opening degree change condition may also be information that is acquired in real time or retrieved, automatically generated and stored each time the electronic expansion valve is changed by a monitoring unit capable of monitoring the opening degree change of the electronic expansion valve.
In step S3, the frequency mode of the inverter pump can represent the current heat exchange requirement of the condenser of the inverter air conditioner, and the change of the opening degree of the electronic expansion valve is directly related to the change of the refrigerant flow in the refrigerant circulation system, which represents the current refrigeration condition of the inverter air conditioner. The frequency conversion pump is operated in a frequency reduction mode at a proper time according to the frequency mode of the frequency conversion pump and the opening change condition of the electronic expansion valve, and the energy consumption of the frequency conversion pump can be reduced based on the current operation requirement of the frequency conversion air conditioner and the current heat exchange requirement of the condenser, so that the energy-saving effect of the frequency conversion air conditioner is further improved.
Further, step S3 includes:
and if the variable frequency pump is in the high-frequency mode and is in the frequency-increasing operation at the first frequency-increasing rate and the opening degree of the electronic expansion valve is reduced, reducing the variable frequency pump to the first set frequency and then in the frequency-increasing operation at the second frequency-increasing rate, wherein the first frequency-increasing rate is greater than the second frequency-increasing rate.
In the above step, the inverter pump operates at the first frequency-increasing rate in the high-frequency mode, which indicates that the heat exchange requirement of the condenser can be met only when the flow rate of the water in the branch circuit absorbing the heat emitted by the condenser and exchanging heat with the condenser is gradually increased in the current heat exchange situation. At this time, if the indoor temperature reaches the set standard of the user, the compressor of the air conditioner operates in a frequency reduction mode, the opening degree of the electronic expansion valve is reduced, the flow of the condenser is reduced, and the heat exchange requirement of the condenser is reduced. Under the condition, the frequency of the variable frequency pump is reduced by a certain amplitude and the frequency increasing rate of the variable frequency pump is reduced based on the frequency change mode in the current operation scheme of the variable frequency pump, so that the heat exchange requirement of the condenser after frequency reduction is met. Wherein, the frequency raising rate represents the frequency raising speed when the variable frequency pump operates in the frequency raising mode. The first frequency increasing rate and the second frequency increasing rate can be set or adjusted according to the actual operation condition of the inverter air conditioner.
Furthermore, the step of reducing the variable frequency pump to the first set frequency and then performing the frequency boosting operation at the second frequency boosting rate includes:
and after the variable frequency pump runs at the current working frequency for a first preset time, the variable frequency pump is reduced to a first set frequency and is subjected to frequency rising running at a second frequency rising rate.
In the above steps, after the variable frequency air conditioner operates in a frequency reduction mode and the opening of the electronic expansion valve is reduced, although the heat exchange requirement of the condenser is reduced by a certain extent, at the initial stage of the heat exchange requirement down regulation, a large amount of waste heat generated by the condenser during heat exchange before the flow rate is reduced is not completely absorbed by the water in the heat exchange branch. At this moment, if the operating frequency of the variable frequency pump is immediately adjusted downwards and the flow of water in the heat exchange branch is reduced, the waste heat around the condenser is possibly difficult to be quickly transferred to the water in the heat exchange branch, so that the condenser is in an environment with higher ambient temperature for a long time, the heat removal speed of the condenser is influenced, and the normal operation of the air conditioner is further influenced. In view of this, if the inverter pump is operated for a period of time at the current operating frequency before the inverter pump is down-converted, a large amount of waste heat of the condenser can be quickly absorbed, and then the flow condition of water of the heat exchange branch is adjusted according to the subsequent heat exchange requirement of the condenser, so that the problem of heat exchange abnormality of the condenser which may occur is solved. The first set frequency can be set according to the actual reduction range of the opening of the electronic expansion valve, the temperature of the operating environment of the inverter air conditioner and the like, as long as the set first set frequency does not affect the normal heat exchange of the condenser. The first preset time can be set according to the actual heat exchange requirement of the condenser before the opening degree of the electronic expansion valve is reduced.
In another possible embodiment, step S3 includes:
and if the variable frequency pump operates in the low frequency mode and the opening degree of the electronic expansion valve is reduced, reducing the variable frequency pump to a second set frequency for operation.
In the above steps, under the condition that the indoor temperature reaches the set standard of the user and the variable frequency air conditioner operates in a frequency reduction mode, the opening degree of the electronic expansion valve is reduced, the flow rate of the refrigerant is reduced, and the heat exchange requirement of the condenser is weakened. At the moment, the variable frequency pump is reduced to the second set frequency to operate, so that the variable frequency pump can adapt to the changed heat exchange requirement of the condenser. Wherein, the second frequency of setting can be set for according to the actual heat transfer demand after the condenser changes.
Further, the step of reducing the variable frequency pump to the second set frequency comprises the following steps:
and after the variable frequency pump runs for a second preset time at the current working frequency, the variable frequency pump is reduced to a second set frequency to run.
In the above steps, before the frequency conversion pump is operated to reduce the frequency, the frequency conversion pump is operated at the current operating frequency for a second preset time so as to absorb a large amount of waste heat of the condenser and then reduce the frequency, thereby avoiding poor heat exchange of the condenser. Similarly, the second set frequency and the second preset time may also be set according to an actual operation requirement of the inverter air conditioner, and there is no association or precedence between the second set frequency and the first preset time, where the "first" and the "second" are only used to distinguish the set frequency and the preset time in different implementation scenarios.
Preferably, before the step of "obtaining the frequency mode of the variable frequency pump", the control method of the present invention further comprises:
acquiring valve opening and closing information of a valve assembly under the condition that the variable frequency pump starts to operate;
determining the current branch operation condition of the heat exchange water channel according to the valve opening and closing information;
the step of obtaining the frequency mode of the variable frequency pump comprises the following steps:
and determining the frequency mode of the variable frequency pump according to the current branch operation condition.
In the above steps, the valve opening/closing information of the valve assembly specifically refers to the opening/closing condition of each valve included in the valve assembly. The method for acquiring the opening and closing conditions of the valves is not limited, and for example, the closing conditions of the valves may be directly detected by a detection element so as to be summarized into the opening and closing information of the valves, or the opening and closing information of the valves may be generated and stored by a control module of the inverter air conditioner after the opening and closing states of the valves are adjusted each time.
The current branch operation condition comprises a specific branch which is currently exchanging heat for the condenser and absorbing heat of the condenser and the operation state of the branch (such as the state of water in the branch which is about to be switched and the state of water in the branch in continuous operation) so as to judge whether the heat exchange condition of the condenser is normal or not and meet the normal operation requirement of the air conditioner by combining the current operation state, and the flow condition of the water in the heat exchange branch is controlled by controlling the operation frequency of the variable frequency pump so as to regulate and control the heat exchange condition of the condenser. In the case where the current frequency mode of the variable frequency pump is determined, the frequency mode can be obtained.
Further, the step of "determining the frequency mode of the variable frequency pump according to the current branch operation condition" includes:
if the heat exchange water path runs by the first heat exchange branch, acquiring the temperature parameter of water in the first heat exchange branch;
and if the temperature parameter is increased and the increased temperature parameter is less than the set temperature, the variable frequency pump is enabled to be operated in the high frequency mode in the frequency increasing mode at the first frequency increasing rate.
In the above step, when the heat exchange water path is operated by the first heat exchange branch, the water in the first heat exchange branch can absorb the heat dissipated by the condenser when flowing through the condenser every time. Under the condition that the water circularly flows in the first heat exchange branch, the temperature of the water is continuously increased. Therefore, when the first heat exchange branch exchanges heat with the condenser, the temperature parameter of water in the first heat exchange branch is obtained, and the heating state of the water can be known, so that whether the water in the branch needs to be continuously heated within a period of time in the follow-up process is judged, whether the current requirement for switching the heat exchange branch exists is determined, the operation requirement of the variable frequency pump is judged according to the change condition of the specific heating requirement, and the operation frequency of the variable frequency pump is further determined; under the condition that the temperature parameter is increased and the increased temperature parameter is smaller than the set temperature, the condition indicates that the water in the first heat exchange branch does not meet the heating stop standard, the branch switching requirement is not met, and the water in the first heat exchange branch needs to be heated. However, the temperature of the water in the first heat exchange branch gradually rises, so that the temperature difference between the water in the first heat exchange branch and the position of the condenser is reduced, and the heat exchange capacity of the first heat exchange branch is gradually weakened. Wherein the set temperature is the temperature of the water after the heating is finished, which is set according to the heating requirement of the water. For example, if water with a maximum temperature of 50 ℃ is required, the temperature parameter of the water in the first heat exchange branch is increased to 50 ℃ during the circulation process, so that the switching requirement of the heat exchange branch is met, and the temperature of 50 ℃ is set at the temperature.
Furthermore, in the case that the variable frequency pump operates in the high frequency mode in an up-conversion mode, the control method of the invention further comprises:
and if the frequency conversion pump is boosted to the maximum working frequency, the heat exchange water route is switched to the second heat exchange branch from the first heat exchange branch, and the frequency conversion pump is switched to the low-frequency mode from the high-frequency mode to run.
In the above step, if the variable frequency pump is raised to the maximum working frequency, it indicates that the promotion effect of the variable frequency pump on the circulating flow of the water in the first heat exchange branch is strongest, and the flow rate of the water flowing through the condenser is maximized. At this time, the temperature of the water in the first heat exchange branch is still in a climbing state, and the heat exchange capacity of the first heat exchange branch is gradually weakened under the condition that the operating power of the variable frequency pump is maximized. In order to ensure the normal heat exchange of the condenser, the heat exchange water route needs to be switched from the first heat exchange branch to the second heat exchange branch, and the variable frequency pump is switched from a high-frequency mode to a low-frequency mode to operate so as to be matched with the second heat exchange branch with constant water temperature and stable heat exchange capacity.
In another possible embodiment, the step of "determining the frequency mode of the variable frequency pump according to the current branch operating condition" further includes:
if the temperature parameter of the water in the first heat exchange water channel is equal to the set temperature, the heat exchange water channel is switched to the second heat exchange branch through the first heat exchange branch, and meanwhile, the variable frequency pump runs in a low-frequency mode.
When the first heat exchange branch exchanges heat with the condenser, if the temperature parameter of the water in the first heat exchange branch is equal to the set temperature, the hot water in the heat exchange water path is heated. At this moment, the branch circuit which exchanges heat with the condenser needs to be switched to the second heat exchange branch circuit, so that the first heat exchange branch circuit stops running, and water in the first heat exchange branch circuit can flow into the water storage device to be insulated. Under the condition that the heat exchange branch is switched to the second heat exchange branch, one end of the second heat exchange branch supplies water, and water in the branch flows out from the water discharge end of the second heat exchange branch after being subjected to heat exchange through the condenser. That is, the water in the second heat exchange branch is not circulated, the initial temperature of the water flowing through the condenser is always the temperature of the supplied water, and the heat exchange capacity of the second heat exchange branch is relatively stable. At this time, the variable frequency pump is operated in a low frequency mode so as to save the supply energy (such as electric energy) of the variable frequency pump while meeting the heat exchange requirement of the condenser.
In another possible case, the step of "determining the operating frequency of the variable frequency pump according to the current branch operating condition" includes:
and if the heat exchange water path runs through the second heat exchange branch, the variable frequency pump runs in a low frequency mode.
In the above steps, in the case that the user has no hot water supply demand, or in the case that the hot water is heated and the inverter air conditioner has switched the heat exchange branch before the last operation is finished, the heat exchange branch may directly operate with the second heat exchange branch when the inverter pump starts to operate. At this moment, the variable frequency pump is operated in a low-frequency mode matched with the second heat exchange branch.
In a preferred embodiment, the control method of the present invention specifically includes the steps of:
acquiring valve opening and closing information of a valve assembly under the condition that the variable frequency pump starts to operate;
determining the current branch operation condition of the heat exchange water channel according to the valve opening and closing information;
under the condition that the heat exchange water path runs by the first heat exchange branch, acquiring the temperature parameter of water in the first heat exchange branch;
if the temperature parameter is increased and the increased temperature parameter is less than the set temperature, the variable frequency pump is enabled to operate in a frequency increasing mode at a first frequency increasing rate;
under the condition of frequency-up operation in a high-frequency mode, if the frequency-up pump is frequency-up to the maximum working frequency, the heat exchange hot water route is switched from the first heat exchange branch to the second heat exchange branch, and meanwhile, the frequency-up pump is switched from the high-frequency mode to the low-frequency mode for operation;
if the temperature parameter of the water in the first heat exchange water channel is equal to the set temperature, the heat exchange water channel is switched from the first heat exchange branch to the second heat exchange branch, and the variable frequency pump runs in a low frequency mode;
under the condition that the heat exchange water path runs through the second heat exchange branch, the variable frequency pump runs in a low frequency mode;
under the condition of determining the frequency mode of the variable frequency pump, acquiring the frequency mode of the variable frequency pump;
acquiring the opening change condition of the electronic expansion valve;
if the variable frequency pump operates in the high-frequency mode in an up-conversion mode at a first up-conversion rate and the opening degree of the electronic expansion valve is reduced, the variable frequency pump operates at the current working frequency for a first preset time, then the variable frequency pump is reduced to a first set frequency and operates in an up-conversion mode at a second up-conversion rate, wherein the first up-conversion rate is greater than the second up-conversion rate;
and if the variable frequency pump operates in the low-frequency mode and the opening degree of the electronic expansion valve is reduced, the variable frequency pump operates at the current working frequency for a second preset time and then is reduced to a second set frequency to operate.
Referring to fig. 2, fig. 2 is a first operation graph of the control method of the inverter air conditioner of the present invention (in the graph, a dotted line is a time-frequency variation curve of the inverter pump, and a solid line is a time-opening degree variation curve of the electronic expansion valve, wherein an upper half of a vertical axis gradually increases from zero to upper frequency, and a lower half of the vertical axis gradually increases from zero to lower opening degree). In one possible embodiment of the present invention, as shown in fig. 2, the inverter pump of the inverter air conditioner of the present invention operates as follows:
under the condition that the inverter air conditioner starts to operate, the electronic expansion valve is closed from the maximum opening degree to the first opening degree so as to enable the air conditioner to quickly form a pressure difference, and therefore the light-load starting of the air conditioner is achieved. Then, the electronic expansion valve is rapidly increased from the first opening degree to the second opening degree (the opening degree is the working opening degree of the electronic expansion valve when the air conditioner is normally cooled). Meanwhile, after the variable frequency air conditioner starts to operate and a period of time passes, the variable frequency pump starts to operate, so that when the water in the heat exchange branch does not flow, the water in the heat branch close to the condenser is utilized to absorb the heat of the condenser, and the energy is saved; after the variable frequency pump starts to operate, rapidly increasing the frequency to the highest frequency reached by the variable frequency pump in the last operation stage when the variable frequency air conditioner operates last time; acquiring valve opening and closing information of the valve assembly, and enabling the variable frequency pump to start frequency-up operation at a first frequency-up rate in a high-frequency mode when the heat exchange water path is determined to operate by the first heat exchange branch and the water of the first heat exchange branch does not reach a set temperature through the valve opening and closing information; when the indoor temperature reaches the temperature set by the user, the variable frequency air conditioner operates in a low frequency mode, the compressor operates in a frequency reduction mode, and the electronic expansion valve is reduced to a third opening degree from a second opening degree (the first opening degree is smaller than the third opening degree and smaller than the second opening degree). In this case, the variable frequency pump is operated at the current working frequency for a first preset time (i.e. a horizontal segment from the m point in fig. 2; the first preset time may be 2min), then is reduced to the first set frequency, and is operated at the second frequency-increasing rate; in the process of the frequency increasing operation of the variable frequency pump, the water in the first heat exchange branch reaches a set temperature, or the operating frequency of the variable frequency pump reaches the maximum (namely the position of an n point in fig. 2), the heat exchange water path is switched to the second heat exchange branch to operate, the variable frequency pump is switched to a low frequency mode, and the variable frequency pump operates at a lower and fixed operating frequency in the low frequency mode until the variable frequency air conditioner is turned off.
Referring to fig. 3, fig. 3 is a first operation graph (in the figure, the dotted line is a time-frequency variation curve of the inverter pump, and the solid line is a time-opening variation curve of the electronic expansion valve, in which the upper half of the vertical axis gradually increases from zero to upper frequency, and the lower half of the vertical axis gradually increases from zero to lower opening) of the control method of the inverter air conditioner of the present invention. In another possible embodiment of the present invention, as shown in fig. 3, the inverter pump of the inverter air conditioner of the present invention operates as follows:
under the condition that the inverter air conditioner starts to operate, the electronic expansion valve is closed from the maximum opening degree to the first opening degree so as to enable the air conditioner to quickly form a pressure difference, and therefore the light-load starting of the air conditioner is achieved. Then, the electronic expansion valve is rapidly increased from the first opening degree to the second opening degree (the opening degree is the working opening degree of the electronic expansion valve when the air conditioner is normally cooled). Meanwhile, after the variable frequency air conditioner starts to operate and a period of time passes, the variable frequency pump starts to operate, so that when the water in the heat exchange branch does not flow, the water in the heat branch close to the condenser is utilized to absorb the heat of the condenser, and the energy is saved; after the variable frequency pump starts to operate, rapidly increasing the frequency to the highest frequency reached by the variable frequency pump in the last operation stage when the variable frequency air conditioner operates last time; acquiring valve opening and closing information of the valve assembly, and enabling the variable frequency pump to start frequency-up operation at a first frequency-up rate in a high-frequency mode when the heat exchange water path is determined to operate by the first heat exchange branch and the water of the first heat exchange branch does not reach a set temperature through the valve opening and closing information; in the process of the frequency increasing operation of the variable frequency pump, the water in the first heat exchange branch reaches a set temperature, or the operation frequency of the variable frequency pump reaches the maximum (namely the position of a p point in fig. 2), the heat exchange water path is switched to the second heat exchange branch to operate, the variable frequency pump is switched to a low frequency mode, and the variable frequency pump operates at a lower fixed working frequency in the low frequency mode; when the indoor temperature reaches the temperature set by the user, the variable frequency air conditioner operates in a low frequency mode, the compressor operates in a frequency reduction mode, and the electronic expansion valve is reduced to a third opening degree from a second opening degree (the first opening degree is smaller than the third opening degree and smaller than the second opening degree). In this case, the inverter pump is operated at the current operating frequency for a second preset time (i.e. a horizontal segment starting from the position of q point in fig. 2; the second preset time may be 2min), and then is reduced to the second preset frequency until the inverter air conditioner is turned off.
In summary, the control method of the inverter air conditioner of the present invention can determine the current branch operation condition of the heat exchange water path according to the valve opening/closing information of the valve assembly. And determining the operating frequency of the variable frequency pump according to different branch operating conditions. Through the variable frequency operation of the variable frequency pump, the heat exchange of the condenser can be realized aiming at different operation conditions of the heat exchange branch when the air conditioner operates, so that the basic operation requirement and the hot water heating requirement of the air conditioner are met, the waste heat recovery is realized, and the energy-saving effect of the air conditioner is further improved. On the basis, the control method can also determine whether the frequency conversion pump needs to reduce the frequency according to the current frequency mode of the frequency conversion pump and the opening degree change condition of the electronic expansion valve, and execute corresponding frequency reduction schemes aiming at different frequency modes of the frequency conversion pump under the condition that the frequency conversion pump needs to reduce the frequency, so that the energy-saving effect of the air conditioner is optimized and improved again.
So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.

Claims (8)

1. A control method of a variable frequency air conditioner is characterized in that the variable frequency air conditioner comprises a compressor, an electronic expansion valve, an evaporator, a condenser and a heat exchange water path, the compressor, the electronic expansion valve, the evaporator and the condenser form a closed-loop refrigerant circulating system, the heat exchange water path comprises a first heat exchange branch, a second heat exchange branch, a variable frequency pump and a valve component, a water storage device is arranged on the first heat exchange branch, a water supply device and a water discharge device are arranged on the second heat exchange branch, any one of the first heat exchange branch and the second heat exchange branch can be communicated with the variable frequency pump, the condenser radiates heat through water flowing in the first heat exchange branch or the second heat exchange branch, and the valve component can enable the heat exchange water path to be switched between the first heat exchange branch and the second heat exchange branch, the variable frequency pump controls the flowing state of water in the first heat exchange branch or the second heat exchange branch,
the control method comprises the following steps:
acquiring a frequency mode of the variable frequency pump;
acquiring the opening change condition of the electronic expansion valve;
according to the frequency mode of the variable frequency pump and the opening degree change condition of the electronic expansion valve, the variable frequency pump is selectively operated in a corresponding frequency reduction mode;
the step of selectively operating the inverter pump in a corresponding frequency reduction mode according to the frequency mode of the inverter pump and the opening degree change condition of the electronic expansion valve comprises the following steps of:
if the variable frequency pump is in the high-frequency mode and is in the frequency-increasing operation at the first frequency-increasing rate and the opening degree of the electronic expansion valve is reduced, the variable frequency pump is reduced to the first set frequency and then is in the frequency-increasing operation at the second frequency-increasing rate,
if the variable frequency pump is operated in a low frequency mode and the opening degree of the electronic expansion valve is decreased, the variable frequency pump is reduced to a second set frequency for operation, wherein,
the first rate of ramping is greater than the second rate of ramping.
2. The control method according to claim 1, wherein the step of reducing the variable frequency pump to a first set frequency and then performing the step of increasing the frequency at a second increasing rate comprises:
and after the variable frequency pump operates at the current working frequency for a first preset time, the variable frequency pump is reduced to a first set frequency and then operates at a second frequency increasing rate in a frequency increasing mode.
3. The control method of claim 1, wherein the step of operating the variable frequency pump down to a second set frequency comprises:
and reducing the frequency of the variable frequency pump to a second set frequency for operation after the variable frequency pump operates at the current working frequency for a second preset time.
4. The control method according to any one of claims 1 to 3, wherein prior to the step of "obtaining the frequency pattern of the variable frequency pump", the control method further comprises:
acquiring valve opening and closing information of the valve assembly;
determining the current branch operation condition of the heat exchange water channel according to the valve opening and closing information;
the step of obtaining the frequency mode of the variable frequency pump comprises the following steps:
and determining the frequency mode of the variable frequency pump according to the current branch circuit running condition.
5. The control method according to claim 4, wherein the step of determining the frequency mode of the variable frequency pump according to the current branch operating condition comprises:
if the heat exchange water path runs by the first heat exchange branch, acquiring the temperature parameter of water in the first heat exchange branch;
and if the temperature parameter is increased and the increased temperature parameter is less than the set temperature, enabling the variable frequency pump to be operated in the high frequency mode at a first frequency increasing rate.
6. The control method of claim 5, wherein in the case where the variable frequency pump is run in an up-conversion mode in a high frequency mode, the control method further comprises:
and if the variable frequency pump is increased to the maximum working frequency, the heat exchange water route is switched to the second heat exchange branch from the first heat exchange branch, and meanwhile, the variable frequency pump is switched to the low-frequency mode from the high-frequency mode to operate.
7. The control method according to claim 4, wherein the step of determining the frequency mode of the variable frequency pump according to the current branch operating condition comprises:
and if the temperature parameter of the water in the first heat exchange water channel is equal to a set temperature, switching the heat exchange water channel from the first heat exchange branch to the second heat exchange branch, and simultaneously operating the variable frequency pump in a low frequency mode.
8. The control method of claim 4, wherein the step of determining the operating frequency of the variable frequency pump based on the current branch operating condition comprises:
and if the heat exchange water path runs through the second heat exchange branch, the variable frequency pump is operated in a low frequency mode.
CN201910636763.8A 2019-07-15 2019-07-15 Control method of variable frequency air conditioner Active CN110500822B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910636763.8A CN110500822B (en) 2019-07-15 2019-07-15 Control method of variable frequency air conditioner

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910636763.8A CN110500822B (en) 2019-07-15 2019-07-15 Control method of variable frequency air conditioner

Publications (2)

Publication Number Publication Date
CN110500822A CN110500822A (en) 2019-11-26
CN110500822B true CN110500822B (en) 2021-10-29

Family

ID=68585305

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910636763.8A Active CN110500822B (en) 2019-07-15 2019-07-15 Control method of variable frequency air conditioner

Country Status (1)

Country Link
CN (1) CN110500822B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113683207A (en) * 2021-09-09 2021-11-23 瑞纳智能设备股份有限公司 Intelligent energy-saving variable-frequency electronic descaling system and control method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004317021A (en) * 2003-04-16 2004-11-11 Matsushita Electric Ind Co Ltd Heat pump water heater
CN102278795A (en) * 2011-07-25 2011-12-14 浙江大学 Central air-conditioning air supply system adopting double cooling coils
CN202254269U (en) * 2011-10-13 2012-05-30 张斗庆 Hot water system of non-bearing double water tank heat pump
CN102865671A (en) * 2012-09-26 2013-01-09 西安交通大学 Variable-flow sewage-source heat pump water heating system utilizing solar energy
CN103388905A (en) * 2013-07-12 2013-11-13 西安交通大学 Evaporator flow-adjustable heat-pump water heater system
CN104075442A (en) * 2014-06-17 2014-10-01 浙江理工大学 Water tank waste water heat recovery heat pump water heater
CN109520053A (en) * 2018-11-30 2019-03-26 上海理工大学 A kind of room air adjusts and hot water supply composite system

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004317021A (en) * 2003-04-16 2004-11-11 Matsushita Electric Ind Co Ltd Heat pump water heater
JP4016875B2 (en) * 2003-04-16 2007-12-05 松下電器産業株式会社 Heat pump water heater
CN102278795A (en) * 2011-07-25 2011-12-14 浙江大学 Central air-conditioning air supply system adopting double cooling coils
CN202254269U (en) * 2011-10-13 2012-05-30 张斗庆 Hot water system of non-bearing double water tank heat pump
CN102865671A (en) * 2012-09-26 2013-01-09 西安交通大学 Variable-flow sewage-source heat pump water heating system utilizing solar energy
CN103388905A (en) * 2013-07-12 2013-11-13 西安交通大学 Evaporator flow-adjustable heat-pump water heater system
CN104075442A (en) * 2014-06-17 2014-10-01 浙江理工大学 Water tank waste water heat recovery heat pump water heater
CN109520053A (en) * 2018-11-30 2019-03-26 上海理工大学 A kind of room air adjusts and hot water supply composite system

Also Published As

Publication number Publication date
CN110500822A (en) 2019-11-26

Similar Documents

Publication Publication Date Title
CN102679482B (en) Heat recovery multiplex system based on variable-frequency air conditioner and control method thereof
CN102032648B (en) Refrigerant flow control method for multi-connected air-conditioning system during heating
US8341973B2 (en) Optimizer for single staged refrigeration systems
CN108895601B (en) Central air conditioner group control method based on magnetic suspension host
US8713952B2 (en) Optimizer for two staged refrigeration systems
US11371764B2 (en) Air conditioning system and control method thereof
CN111089440A (en) Water-cooling air conditioning system and control method
CN112880115A (en) Control method of multi-unit air conditioning system
CN101865507A (en) Air conditioner system energy saving method and device
CN108019890B (en) Air conditioner energy efficiency control method and device and air conditioner system
CN110500822B (en) Control method of variable frequency air conditioner
CN102777981A (en) Energy-saving air-conditioning system used for communication base station and capable of supplying air in object-oriented mode and running method thereof
KR20140097776A (en) Inverter type air conditioner system for vehicle
CN109764436B (en) Heat pump energy storage system for stabilizing short-term fluctuation of intermittent energy
JP2009264718A (en) Heat pump hot water system
CN110500821B (en) Control method of variable frequency air conditioner
CN102135302A (en) Machine room energy-saving heat radiating system and control method thereof
KR200412598Y1 (en) Heat pump system for having function of hot water supply
JP2009264682A (en) Water heat source air conditioner
CN110513924B (en) Control method of fixed-frequency air conditioner
CN102748892A (en) Movable-type heat pump device for partial heating/refrigerating
CN104896699A (en) Motor radiating structure, air conditioner and motor radiating method
CN112594895B (en) Intelligent regulation and control method and system for temperature of outdoor unit
KR101078162B1 (en) Hot and cool water, heating and cooling heat-pump system
KR100755324B1 (en) Electric generation air condition system and the Control method for the Same

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