CN114413498B

CN114413498B - Air conditioner jet circulation system and control method thereof

Info

Publication number: CN114413498B
Application number: CN202210118641.1A
Authority: CN
Inventors: 赖桃辉; 黄玉优; 林海佳; 任启峰
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2022-02-08
Filing date: 2022-02-08
Publication date: 2023-09-12
Anticipated expiration: 2042-02-08
Also published as: CN114413498A

Abstract

The invention provides an air conditioner jet circulation system and a control method thereof, wherein the system comprises: a main circulation flow path including a compressor, a condenser, a switching valve, an injection port of an injector, and a gas-liquid separator; the heat exchange flow path comprises a first heat exchanger and a second heat exchanger, the first heat exchanger is communicated with the bottom of the gas-liquid separator through a first throttling element, the first heat exchanger is simultaneously communicated with the switching valve and the ejector, the second heat exchanger is communicated with one side, far away from the first heat exchanger, of the first throttling element through a second throttling element, and the second heat exchanger is communicated with the switching valve; the switching valve comprises a first state and a second state, the ejector is communicated with the condenser in the first state, and the first heat exchanger is communicated with the second heat exchanger; in the second state, the condenser is in communication with the second heat exchanger and the ejector is in communication with the first heat exchanger. According to the invention, the system composition structure can be greatly simplified, the control logic is further simplified, and the system construction cost is reduced.

Description

Air conditioner jet circulation system and control method thereof

Technical Field

The invention belongs to the technical field of air conditioning, and particularly relates to an air conditioner jet circulation system and a control method thereof.

Background

At present, in the field of machine room air conditioning, a variable frequency air conditioning system can adjust the refrigerating capacity output of a refrigerating unit according to the heat load of a data center, so that load matching is realized, and the constant temperature and humidity requirements of a data machine room are met. However, due to the high requirements of the data center on the indoor temperature and humidity precision, the machine room air conditioner which requires refrigeration output all the year round needs to often cope with the situations of heat load fluctuation and humidity load fluctuation.

The problem that the humidity of a data center is too large or too small easily occurs in the control of the humidity of the data center, the condensed water easily occurs in the case of too large humidity, static electricity easily occurs in the case of too small humidity, and the safe operation of data center equipment can be seriously threatened in both cases. In the south, cold and damp weather is very easy to occur, the indoor humidity of the data center is overlarge due to the fact that a data center enclosure structure or moisture vapor invaded through doors and windows, and the dehumidification capability of a machine room air conditioner is required to be increased, so that the evaporation temperature is too low, and the indoor air supply temperature is too high in fluctuation. Particularly, under the condition of high humidity and low load of the data center, the contradiction phenomenon exists in the operation of the air conditioner of the machine room: the unit is matched with low-load output, the indoor wet load cannot be reduced due to the fact that the dehumidification capacity is reduced, and the problem of light-load dehumidification is solved; the increased dehumidification capability meets the indoor humidity requirement and exceeds the heat load requirement, so that the indoor temperature is reduced too greatly.

The latter common solution is to utilize the cold air after electric heating reheating and dehumidification to ensure that the refrigerating output of the air conditioner of the machine room is not too large, thereby realizing the constant temperature requirement of the data center, but the electric heating reheating mode is a mode which wastes electric energy, and the energy saving is a very urgent problem under the huge electric energy requirement of the data center.

Therefore, how to solve the constant temperature and humidity control problem of the machine room air conditioner of the data center under the light load dehumidification condition and how to reduce the electric energy waste problem during the light load dehumidification operation is a technical difficulty which needs to be solved by the energy-saving efficient machine room air conditioner. In the prior art CN106247655B, the serial operation of evaporators is realized by an electromagnetic four-way valve reversing mode, refrigerants with different temperatures pass through different evaporators successively, the rear low-temperature evaporator dehumidifies and simultaneously utilizes the front high-temperature evaporator to reheat cold air, and the technology can well realize light-load constant-temperature dehumidification without additional electric heating and reheating air, so that the two problems are effectively solved. However, the CN106247655B technology requires that the evaporator is divided into two parts, and the refrigeration operation under either condition is that the evaporators are operated in series, the evaporation phase change process of the refrigerant is too long, and there may be a problem of large resistance, which results in the energy efficiency reduction of the refrigeration unit; the electromagnetic four-way valve used in the technology is arranged at the outlet of the condenser, and under the condition of conventional refrigeration operation, liquid refrigerant flows through the four-way valve, so that adverse effects such as leakage of the refrigerant in the valve, easy cancellation of the cold quantity and heat quantity of the refrigerant and the like are easily caused.

The above problems are mainly discussed with respect to data centers, and in practical comfort air conditioners for civil use and business use, indoor dehumidification demands in cold weather often occur. The common dehumidification mode of the current comfortable air conditioner is that the low-wind-speed refrigeration operation is carried out in most of the actual low-evaporation temperature modes, the indoor temperature is reduced along with the low-evaporation-temperature refrigeration operation, so that the temperature of the user body is reduced, and the user body is uncomfortable, and therefore, a special dehumidifier is adopted in many occasions to solve the problem.

In order to solve the above problems, the present inventors have proposed an air conditioner injection circulation system with dual ejectors and a switching valve, which can realize different refrigerant flow paths by switching the switching valve and switching on and off the two ejectors, thereby meeting the requirements of cascade refrigeration or light-load dehumidification, but the air conditioner injection circulation system has complex system composition and control logic, and has high system construction cost.

Disclosure of Invention

Therefore, the invention provides the air conditioner jet circulation system and the control method thereof, which can overcome the defects of complex system composition and control logic and high system construction cost of the air conditioner jet circulation system in the prior art.

In order to solve the above problems, the present invention provides an air conditioner spray circulation system, comprising:

the main circulation flow path comprises a compressor, a condenser, a switching valve, an injection port of the injector and a gas-liquid separator which are sequentially arranged along the flow direction of the working medium;

the heat exchange flow path comprises a first heat exchanger and a second heat exchanger which are respectively positioned at the upstream and downstream of a heat exchange airflow, a first port of the first heat exchanger is communicated with the bottom of the gas-liquid separator through a first throttling element, a second port of the first heat exchanger is simultaneously communicated with the switching valve and an injection port of the injector, a first port of the second heat exchanger is communicated with one side, away from the first heat exchanger, of the first throttling element through a second throttling element, and a second port of the second heat exchanger is communicated with the switching valve;

the switching valve comprises a first state and a second state, wherein in the first state, an injection port of the injector is communicated with an outlet of the condenser, and a second port of the first heat exchanger is communicated with a second port of the second heat exchanger; in the second state, the outlet of the condenser is communicated with the second port of the second heat exchanger, and the injection port of the injector is communicated with the second port of the first heat exchanger.

In some embodiments of the present invention, in some embodiments,

the pipeline between the first throttling element and the gas-liquid separator is provided with a one-way valve, the second throttling element is connected with the first throttling element at a first point, the one-way valve is positioned between the gas-liquid separator and the first point, and the one-way valve only allows working medium to flow from the gas-liquid separator to the first throttling element and the second throttling element.

In some embodiments of the present invention, in some embodiments,

the switching valve is a four-way valve, the four-way valve is provided with a D port, an E port, an S port and a C port, and when the switching valve is in the first state, the D port is communicated with the C port, and the E port is communicated with the S port; when the switching valve is in the second state, the D port is communicated with the E port, and the C port is communicated with the S port.

In some embodiments of the present invention, in some embodiments,

when the air conditioner jet circulation system runs in the jet refrigeration mode, the switching valve is in a first state, so that gaseous working medium flowing out of the condenser and flowing into the gas-liquid separator is sucked into the compressor, and liquid working medium in the gas-liquid separator enters the first heat exchanger and the second heat exchanger in parallel and flows out of the injection port integrated in the injector.

In some embodiments of the present invention, in some embodiments,

when the air conditioner jet circulation system runs in a conventional dehumidification mode or a light-load dehumidification mode, the switching valve is in a second state, so that working media flowing out of the condenser sequentially flow through the second heat exchanger and the first heat exchanger, flow into the gas-liquid separator through the jet orifice and the injection orifice of the ejector, and are then sucked into the compressor.

In some embodiments of the present invention, in some embodiments,

the first heat exchanger and the second heat exchanger share an inner fan, and the rotating speed of the inner fan in the light-load dehumidification mode is lower than that in the conventional dehumidification mode.

The invention also provides a control method of the air conditioner jet circulation system, which is used for controlling the air conditioner jet circulation system and comprises the following steps:

acquiring an operation mode of a system;

and controlling to switch the state of the switching valve according to the acquired operation mode.

In some embodiments of the present invention, in some embodiments,

when the operation mode is an injection refrigeration mode, the switching valve is controlled to be in a first state, so that gaseous working medium flowing out of the condenser flows into the gas-liquid separator and is sucked into the compressor, and liquid working medium in the gas-liquid separator enters the first heat exchanger and the second heat exchanger in parallel and flows out of the injection port integrated in the injector.

In some embodiments of the present invention, in some embodiments,

when the air conditioner jet circulation system runs in a conventional dehumidification mode or a light-load dehumidification mode, the switching valve is controlled to be in a second state, so that working medium flowing out of the condenser flows through the second heat exchanger and the first heat exchanger in sequence, flows into the gas-liquid separator through the jet orifice and the injection orifice of the ejector, and is then sucked into the compressor.

In some embodiments, prior to acquiring the system mode of operation, further comprising:

acquiring the real-time return air temperature T of the heat exchange flow path _{Returning to} Real-time return air humidity RH _{Returning to} ，

When T is _{Returning to} ＞T _{Is provided with} When the temperature is plus delta T, the control system enters an injection refrigeration mode; or alternatively, the process may be performed,

when T is _{Is provided with} ＜T _{Returning to} ＜T _{Is provided with} + [ delta ] T and RH _{Returning to} ≥RH _{Is provided with} When +A is delta RH, the control system enters a conventional dehumidification mode; or alternatively, the process may be performed,

when T is _{Is provided with} -B*△T≤T _{Returning to} ≤T _{Is provided with} And RH (RH) _{Returning to} ≥RH _{Is provided with} When the delta RH is in the range of the delta RH, the control system enters a light-load dehumidification mode，

Wherein DeltaT is a temperature precision set value, T _{Is provided with} To set the temperature, RH _{Is provided with} For setting humidity, Δrh is a humidity accuracy setting value, a is a humidity setting coefficient, and B is a temperature setting coefficient.

According to the air conditioner jet circulation system and the control method thereof, on one hand, when the switching valve is in the first state, the first heat exchanger and the second heat exchanger in the system form cascade refrigeration on air flow in the air conditioning space, when the switching valve is in the second state, the air flow is dehumidified through the first heat exchanger, the dehumidified cooling gas is heated through the second heat exchanger by utilizing condensation heat, constant-temperature dehumidification is realized, electric energy consumption is not required to be consumed by independently arranging corresponding electric heating parts, and the energy saving performance of the system is better; on the other hand, when the switching valve is in the first state, working medium in the switching valve leaks and then enters the gas-liquid separator at the outlet of the ejector to realize gas-liquid separation, and the working medium cannot directly enter the compressor, so that the energy efficiency of the system is ensured; on the other hand, the technical scheme adopts a single ejector to be combined with the first throttling element and the second throttling element, and realizes different operation modes to be switched through the switching valve, so that the system composition structure can be greatly simplified, the control logic is further simplified, and the system construction cost is reduced.

Drawings

Fig. 1 is a schematic system diagram of an air conditioner spray circulation system according to an embodiment of the present invention, in which a switching valve is in a first state;

fig. 2 is a schematic system diagram of an air conditioner spray circulation system according to an embodiment of the present invention, in which a switching valve is in a second state;

fig. 3 is a schematic control flow chart (operation mode judgment) of an air conditioner spray circulation system according to another embodiment of the invention.

The reference numerals are expressed as:

1. a compressor; 2. a condenser; 3. a switching valve; 4. an ejector; 5. a gas-liquid separator; 61. a first heat exchanger; 62. a second heat exchanger; 71. a first throttling element; 72. a second throttling element; 8. a one-way valve; 91. an inner fan; 92. an external fan.

Detailed Description

Referring to fig. 1 to 3 in combination, according to an embodiment of the present invention, there is provided an air conditioner spray circulation system including: the main circulation flow path comprises a compressor 1, a condenser 2, a switching valve 3, an injection port of an injector 4 and a gas-liquid separator 5 which are sequentially arranged along the flow direction of working medium; a heat exchange flow path including a first heat exchanger 61 and a second heat exchanger 62 which are respectively positioned at the upstream and downstream of the heat exchange air flow, wherein a first port of the first heat exchanger 61 is communicated with the bottom of the gas-liquid separator 5 through a first throttling element 71, a second port of the first heat exchanger 61 is simultaneously communicated with the switching valve 3 and the injection port of the injector 4, a first port of the second heat exchanger 62 is communicated with one side of the first throttling element 71 away from the first heat exchanger 61 through a second throttling element 72, and a second port of the second heat exchanger 62 is communicated with the switching valve 3; wherein the switching valve 3 includes a first state in which the injection port of the injector 4 communicates with the outlet of the condenser 2, and a second state in which the second port of the first heat exchanger 61 communicates with the second port of the second heat exchanger 62; in the second state, the outlet of the condenser 2 communicates with the second port of the second heat exchanger 62, and the injection port of the ejector 4 communicates with the second port of the first heat exchanger 61.

In the technical scheme, on one hand, when the switching valve 3 is in a first state, the first heat exchanger 61 and the second heat exchanger 62 in the system form cascade refrigeration on the air flow in the air conditioning space, and when the switching valve 3 is in a second state, the air flow is dehumidified through the first heat exchanger 61, the dehumidified cooling gas is heated through the second heat exchanger 62 by utilizing condensation heat, so that constant-temperature dehumidification is realized, the corresponding electric heating components do not need to be independently arranged to consume electric energy, and the energy saving performance of the system is better; on the other hand, when the switching valve 3 is in the first state, the working medium in the switching valve 3 leaks and then enters the gas-liquid separator 5 at the outlet of the ejector 4 to realize gas-liquid separation, and the working medium cannot directly enter the compressor 1, so that the energy efficiency of the system is ensured; on the other hand, in the technical scheme, the single ejector 4 is combined with the first throttling element 71 and the second throttling element 72, and different operation modes are switched through the switching valve 3, so that the system composition structure can be greatly simplified, the control logic is further simplified, and the system construction cost is reduced.

The working medium refers to medium substances which are used by various heat engines or thermodynamic equipment to finish the mutual conversion of heat energy and mechanical energy, and is commonly water, refrigerant, air and the like.

In order to ensure smooth circulation of the working medium, the working medium in the gas-liquid separator 5 should be limited to flow from the gas-liquid separator 5 to the first heat exchanger 61 or the second heat exchanger 62 side only, but not to the reverse direction, which can be ensured by providing a pressure detection sensor at the O-point shown in fig. 1 or fig. 2 (i.e. the connection position of the first throttling element 71 and the second throttling element 72 and the outlet of the gas-liquid separator 5) to feed back the flow direction, whereas as a more simplified design, a check valve 8 is provided on the line between the first throttling element 71 and the gas-liquid separator 5, the second throttling element 72 and the first throttling element 71 being connected to a first point, the check valve 8 being located between the gas-liquid separator 5 and the first point, the check valve 8 allowing only flow of the working medium from the gas-liquid separator 5 to the first throttling element 71 and the second throttling element 72.

In some embodiments, the switching valve 3 is a four-way valve having a D port, an E port, an S port, and a C port, the D port being in communication with the C port and the E port being in communication with the S port when the switching valve 3 is in the first state; when the switching valve 3 is in the second state, the D port is communicated with the E port, and the C port is communicated with the S port, so that the four-way flow path switching characteristic of the four-way valve can be utilized to further simplify the system structural design.

In some embodiments, when the air-conditioning injection circulation system operates in the injection refrigeration mode, the switching valve 3 is in the first state, so that the gaseous working medium flowing out of the condenser 2 after flowing into the gas-liquid separator 5 is sucked into the compressor 1, and the liquid working medium in the gas-liquid separator 5 enters the first heat exchanger 61 and the second heat exchanger 62 in parallel and then flows out of the injection port of the injector 4 together, in this mode, the first heat exchanger 61 and the second heat exchanger 62 are connected in parallel, and form cascade refrigeration on the flowing heat exchange airflow together, and the corresponding first throttling element 71 and the second throttling element 72 respectively adjust the corresponding opening according to the control logic in the injection refrigeration mode. Specifically, for example, the opening degree of the first throttling element 71 is controlled by detecting the superheat degree of the exhaust gas of the compressor 1, the flow rate of the working medium entering the first heat exchanger 61 is adjusted, the opening degree of the second throttling element 72 is controlled by detecting the temperature of the outlet air of the heat exchange flow path, and the flow rate of the working medium entering the second heat exchanger 72 is adjusted so as to achieve the constant-temperature dehumidification effect.

In some embodiments, when the air-conditioning injection circulation system operates in the normal dehumidification mode or the light-load dehumidification mode, the switching valve 3 is in the second state, so that the working medium flowing out of the condenser 2 flows through the second heat exchanger 62 and the first heat exchanger 61 in sequence, flows into the gas-liquid separator 5 through the injection port and the injection port of the injector 4, and is then sucked into the compressor 1, in this mode, the first heat exchanger 61 and the second heat exchanger 62 form a series connection, the first heat exchanger 61 is used as an evaporator for dehumidification, the second heat exchanger 62 is used as a secondary condenser for reheating, and the corresponding first throttling element 71 and the second throttling element 72 respectively adjust the corresponding opening according to the control logic in the injection refrigeration mode.

In some embodiments, the first heat exchanger 61 and the second heat exchanger 62 share an inner fan 91, and the rotation speed of the inner fan 91 in the light-load dehumidification mode is lower than that in the normal dehumidification mode, so as to meet the requirements of dehumidification and constant temperature under the light-load working condition. The first throttling element 71 and the second throttling element 72 are both electronic expansion valves, so that the opening degrees of the two are controlled respectively.

According to an embodiment of the present invention, there is also provided a control method of an air conditioner spray circulation system for controlling the above air conditioner spray circulation system, including:

acquiring an operation mode of a system;

and controlling to switch the state of the switching valve 3 according to the acquired operation mode.

Specifically, when the operation mode is an injection refrigeration mode, the switching valve 3 is controlled to be in a first state, so that the gaseous working medium after the working medium flowing out of the condenser 2 flows into the gas-liquid separator 5 is sucked into the compressor 1, and the liquid working medium in the gas-liquid separator 5 enters the first heat exchanger 61 and the second heat exchanger 62 in parallel and flows out of the injection port integrated in the injector 4;

when the air-conditioning injection circulation system operates in the normal dehumidification mode or the light-load dehumidification mode, the switching valve 3 is controlled to be in the second state, so that the working medium flowing out of the condenser 2 flows through the second heat exchanger 62 and the first heat exchanger 61 in sequence, flows into the gas-liquid separator 5 through the injection port and the injection port of the injector 4, and is then sucked into the compressor 1.

While it will be appreciated that when the system is operating in the light load dehumidification mode, the operating frequency of the compressor 1 (when it is a variable frequency compressor) may be reduced in addition to the speed of the inner blower 91 being reduced as compared to the conventional dehumidification mode.

The operation mode may be selected by a user through a mode selection button on the controller, for example, and in some embodiments, as shown in fig. 3, before acquiring the system operation mode, the method further includes: acquiring the real-time return air temperature T of the heat exchange flow path _{Returning to} Real-time return air humidity RH _{Returning to} When T _{Returning to} ＞T _{Is provided with} When the temperature is plus delta T, the control system enters an injection refrigeration mode; alternatively, when T _{Is provided with} ＜T _{Returning to} ＜T _{Is provided with} + [ delta ] T and RH _{Returning to} ≥RH _{Is provided with} When +A is delta RH, the control system enters a conventional dehumidification mode; alternatively, when T _{Is provided with} -B*△T≤T _{Returning to} ≤T _{Is provided with} And RH (RH) _{Returning to} ≥RH _{Is provided with} When delta RH is in a low-load dehumidification mode, the control system enters a light-load dehumidification mode, wherein delta T is a temperature precision set value, and T _{Is provided with} To set the temperature, RH _{Is provided with} For setting humidity, ΔRH is a humidity precision set point, A is a humidity set coefficient, B is a temperature set coefficient, A, B is a specific value according to the test condition, in one specific embodiment, A is in the range of 1-2,preferably A is 3/2; the value of B is in the range of 0 to 1, and preferably, B is 1/2.

Therefore, the intelligent identification and automatic switching of the operation modes of the system are realized, and the air conditioning space is better in adjusting effect.

The technical scheme of the invention is further described below with reference to fig. 1 to 3:

an air conditioner injection circulation system, in particular to a light-load dehumidification air conditioner injection circulation system, which consists of a compressor 1, a condenser 2, an outer fan 92, a four-way valve (namely a switching valve 3, the same applies hereinafter), an ejector 4, an inner fan 91, an evaporator A (namely a first heat exchanger 61, the same applies hereinafter), an evaporator B (namely a second heat exchanger 62, the same applies hereinafter), an expansion valve A (namely a first throttling element 71, the same applies hereinafter), an expansion valve B (namely a second throttling element 72, the same applies hereinafter), a one-way valve 8, a gas-liquid separator 5 and the like.

It has the following two operation modes:

a. injection cycle cooling mode: the mode is a conventional refrigeration mode of the unit and is used for cooling. At the moment, the four-way valve is communicated with the C, the E is communicated with the S, and the circulating flow direction of the system refrigerant is as follows: the high-temperature high-pressure gaseous refrigerant discharged by the compressor is changed into a high-temperature liquid refrigerant after passing through the condenser, and the high-temperature liquid refrigerant flows through D and C to enter the ejector under the action of the four-way valve; meanwhile, the low-temperature gaseous refrigerant from the evaporator B passes through the four-way valves E and S, is mixed with the low-temperature gaseous refrigerant from the evaporator A, enters the ejector, is mixed in the mixing section in the ejector, is pressurized by the ejector, enters the gas-liquid separator, and is sucked by the compressor and discharged into the condenser under the action of the gas-liquid separator; the liquid refrigerant flows through the expansion valve A and the expansion valve B under the underflow of the gas-liquid separator, forms low-temperature low-pressure refrigerant under the throttling effect of the expansion valve, and then enters the evaporator A and the evaporator B respectively, the liquid refrigerant of the evaporator A and the evaporator B absorbs indoor heat and then becomes low-temperature low-pressure gaseous refrigerant to be mixed and then enters the ejector, and the liquid refrigerant circulates in a reciprocating manner, wherein the one-way valve can prevent the refrigerant from reversely entering the gas-liquid separator.

b. Light-load dehumidification mode (the flow path control in the normal dehumidification mode is the same as that in the normal dehumidification mode, and only the light-load dehumidification mode is described here as an example): the mode is a dehumidification mode under low load, at the moment, the four-way valve is communicated with the D and the E, the S and the C, and the circulating flow direction of the system refrigerant is as follows: the compressor discharges high-temperature high-pressure gaseous refrigerant, the high-temperature high-pressure gaseous refrigerant enters the condenser to be changed into high-temperature liquid refrigerant, the high-temperature high-pressure liquid refrigerant is formed by flowing through D and E and enters the evaporator B under the action of the four-way valve, the low-temperature low-pressure liquid refrigerant is formed by flowing through D and E under the action of the expansion valve B, the high-temperature high-pressure liquid refrigerant is mixed with the liquid refrigerant discharged from the bottom of the gas-liquid separator and then passes through the expansion valve, the liquid refrigerant is further throttled and cooled, the liquid refrigerant enters the evaporator A, the endothermic gasification is changed into low-temperature gaseous refrigerant, the low-temperature gaseous refrigerant is divided into two paths, one path of the low-temperature high-pressure gaseous refrigerant flows through the four-way valve S and C and enters the ejector, the other path of the low-temperature high-pressure gaseous refrigerant is directly enters the ejector and then enters the gas-liquid separator after being mixed with the gaseous refrigerant flowing through the four-way valve, the gaseous refrigerant is sucked by the compressor and discharged by the high-temperature high-pressure gaseous refrigerant enters the condenser, and the reciprocating circulation is performed, and the one-way valve can prevent the refrigerant from reversely entering the gas-liquid separator.

See fig. 3, wherein: t (T) _{Returning to} : return air temperature T _{Is provided with} : setting a temperature, deltaT: temperature accuracy set point, RH _{Returning to} : return air humidity, RH _{Is provided with} : humidity setting, Δrh: humidity accuracy setting value, coefficient: A. and B, according to the test conditions.

After the unit is electrified, the temperature and humidity of the current room are detected by a return air temperature and humidity detection device of the unit:

1. when detecting T _{Returning to} >T _{Is provided with} When delta T is exceeded, judging that the current environment needs to be cooled to meet the set requirement, controlling the four-way valve D to be communicated with C, and controlling the four-way valve E to be communicated with S, and starting an injection refrigeration mode of the unit, wherein the refrigerant circulation is as described in the injection circulation refrigeration mode, in the mode, the opening of the expansion valve A and the opening of the expansion valve B are controlled through the superheat degree, and if the variable-frequency compressor is configured by the system, the frequency of the compressor and the like can be regulated through the return air temperature detection value and the return air temperature target value, and the flow of the refrigerant entering the evaporator A and the evaporator B can be regulated together, so that the refrigerating capacity of the unit reaches the maximum, and the rapid cooling can reach the target value rapidly;

2. when T is detected _{Is provided with} <T _{Returning to} <T _{Is provided with} And RH returns to be equal to or greater than RH _{Is provided with} When +A.DELTA.RH precision (example: a is 3/2), the ambient temperature is in the set range, but the humidity is higher, the dehumidification capacity is required to be increased, the refrigerating capacity of the unit is reduced, the unit operates in a conventional dehumidification mode, the air quantity of the evaporation side of the unit is reduced on the basis of injection refrigeration circulation in the mode, if the variable-frequency compressor is configured in the system, the variable-frequency compressor can synchronously reduce the frequency so as to reduce the evaporation temperature of the evaporator A and the evaporator B, the dehumidification effect is increased while the cold output is reduced, the unit is enabled to dehumidify rapidly, the four-way valve is not commutated at the moment, and the circulation mode of the system refrigerant is unchanged.

3. When T is detected _{Is provided with} -B*△T<T _{Returning to} ≤T _{Is provided with} And RH (RH) _{Returning to} ≥RH _{Is provided with} When the temperature is plus delta RH (1/2 is taken in an example: B), the unit cooling capacity output is required to be small, but the humidity is higher, and further dehumidification is required while the temperature is maintained stable, so as to avoid humidity fluctuation, even incapacity of dehumidification, caused by frequent start and stop of the compressor or long-time low-frequency operation of the variable-frequency compressor and oil return operation, and the unit is started in a light-load dehumidification mode. The refrigerant circulation is shown in the light-load dehumidification mode, in the mode, the variable-frequency compressor can keep higher frequency, the fixed-frequency compressor can realize non-stop operation, the evaporator A performs stable dehumidification, the evaporator B performs reheating on the cooling air flow of the evaporator A, at the moment, the opening of the expansion valve A is controlled through the superheat degree of exhaust, and the evaporation temperature of the evaporator A is regulated to ensure the dehumidification effect; the opening of the expansion valve B is controlled through the air outlet temperature, the evaporation temperature of the evaporator B is regulated, the air supply temperature is ensured to be in a control requirement range, and constant-temperature dehumidification is realized.

It will be readily appreciated by those skilled in the art that the above advantageous ways can be freely combined and superimposed without conflict.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention. The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that modifications and variations can be made without departing from the technical principles of the present invention, and these modifications and variations should also be regarded as the scope of the invention.

Claims

1. An air conditioner spray circulation system, comprising:

the main circulation flow path comprises a compressor (1), a condenser (2), a switching valve (3), an injection port of an injector (4) and a gas-liquid separator (5) which are sequentially arranged along the flow direction of a working medium;

a heat exchange flow path comprising a first heat exchanger (61) and a second heat exchanger (62) which are respectively positioned at the upstream and downstream of a heat exchange airflow, wherein a first port of the first heat exchanger (61) is communicated with the bottom of the gas-liquid separator (5) through a first throttling element (71), a second port of the first heat exchanger (61) is simultaneously communicated with the switching valve (3) and the injection port of the injector (4), a first port of the second heat exchanger (62) is communicated with one side, far away from the first heat exchanger (61), of the first throttling element (71) through a second throttling element (72), and a second port of the second heat exchanger (62) is communicated with the switching valve (3);

wherein the switching valve (3) comprises a first state in which the injection port of the injector (4) communicates with the outlet of the condenser (2), and a second state in which the second port of the first heat exchanger (61) communicates with the second port of the second heat exchanger (62); in the second state, the outlet of the condenser (2) is communicated with the second port of the second heat exchanger (62), the injection port of the ejector (4) is communicated with the second port of the first heat exchanger (61), and the number of the ejectors (4) is 1.

2. The air conditioner spray circulation system of claim 1, wherein,

the one-way valve (8) is arranged on a pipeline between the first throttling element (71) and the gas-liquid separator (5), the second throttling element (72) and the first throttling element (71) are connected to a first point, the one-way valve (8) is positioned between the gas-liquid separator (5) and the first point, and the one-way valve (8) only allows working medium to flow from the gas-liquid separator (5) to the first throttling element (71) and the second throttling element (72).

3. The air conditioner spray circulation system according to claim 1 or 2, wherein,

the switching valve (3) is a four-way valve, the four-way valve is provided with a D port, an E port, an S port and a C port, and when the switching valve (3) is in the first state, the D port is communicated with the C port, and the E port is communicated with the S port; when the switching valve (3) is in the second state, the port D is communicated with the port E, and the port C is communicated with the port S.

4. An air conditioner spray circulation system according to any one of claims 1 to 3,

when the air conditioner jet circulation system runs in the jet refrigeration mode, the switching valve (3) is in a first state, so that the gaseous working medium flowing out of the condenser (2) flows into the gas-liquid separator (5) and is sucked into the compressor (1), and the liquid working medium in the gas-liquid separator (5) enters the first heat exchanger (61) and the second heat exchanger (62) in parallel and flows out of the injection port integrated in the ejector (4).

5. An air conditioner spray circulation system according to any one of claims 1 to 3,

when the air conditioner jet circulation system runs in a conventional dehumidification mode or a light-load dehumidification mode, the switching valve (3) is in a second state, so that working media flowing out of the condenser (2) sequentially flow through the second heat exchanger (62) and the first heat exchanger (61) and then flow into the gas-liquid separator (5) through the jet orifice and the injection orifice of the ejector (4) to be sucked into the compressor (1).

6. The air conditioner spray circulation system of claim 5, wherein,

the first heat exchanger (61) and the second heat exchanger (62) share an inner fan (91), and the rotating speed of the inner fan (91) in the light-load dehumidification mode is lower than that in the normal dehumidification mode.

7. A control method of an air conditioner spray circulation system, characterized by being used for controlling the air conditioner spray circulation system according to any one of claims 1 to 6, comprising:

acquiring an operation mode of a system;

and controlling to switch the state of the switching valve (3) according to the acquired operation mode.

8. The control method according to claim 7, wherein,

when the operation mode is an injection refrigeration mode, the switching valve (3) is controlled to be in a first state, so that the gaseous working medium flowing out of the condenser (2) flows into the gas-liquid separator (5) and is sucked into the compressor (1), and the liquid working medium in the gas-liquid separator (5) enters the first heat exchanger (61) and the second heat exchanger (62) in parallel and flows out of the injection port integrated in the injector (4).

9. The control method according to claim 7, wherein,

when the air conditioner jet circulation system runs in a conventional dehumidification mode or a light-load dehumidification mode, the switching valve (3) is controlled to be in a second state, so that working media flowing out of the condenser (2) sequentially flow through the second heat exchanger (62) and the first heat exchanger (61) and then flow into the gas-liquid separator (5) through the jet orifice and the jet orifice of the ejector (4) to be sucked into the compressor (1).

10. The control method according to claim 7, characterized by further comprising, before acquiring the system operation mode:

when T is _{Is provided with} ＜T _{Returning to} ＜T _{Is provided with} +△T and RH _{Returning to} ≥RH _{Is provided with} When +A is delta RH, the control system enters a conventional dehumidification mode; or alternatively, the process may be performed,

when T is _{Is provided with} -B*△T≤T _{Returning to} ≤T _{Is provided with} And RH (RH) _{Returning to} ≥RH _{Is provided with} When the temperature is plus delta RH, the control system enters a light-load dehumidification mode,