Data center air conditioner with waste heat recovery function and operation control method thereof

Abstract

The invention relates to the technical field of data center machine room air conditioners, in particular to a data center air conditioner with a waste heat recovery function and an operation control method thereof. The data center air conditioner comprises a waste heat recovery module and two sets of refrigeration modules. The waste heat recovery module comprises a plate heat exchanger, a two-way adjusting valve, a water flow sensor, a water inlet temperature sensor and a water outlet temperature sensor. The operation control method of the data center air conditioner comprises the following steps that when the air conditioner enters a waste heat recovery state, an inlet A and an outlet B of a first three-way valve are connected, and an inlet A and an outlet C of the first three-way valve are disconnected for judgment and adjustment; when the waste heat recovery state is quitted, the inlet A and the outlet B of the first three-way valve are disconnected, and the inlet A and the outlet C are connected for judgment and adjustment; by means of the mode, aiming at the phenomenon of heat waste of the data center, the system stability is improved while waste heat recovery is met.

Description

Technical Field

[0001] The present invention relates to the technical field of data center computer room air conditioners, and in particular to a data center air conditioner with a waste heat recovery function and an operation control method thereof. Background Art

[0002] With the development of the data center industry, the power density of servers has gradually increased, and the power consumption of data centers has also increased dramatically. In order to ensure the normal operation of server equipment, data centers need to consume a lot of energy for cooling. Traditional data center computer room air conditioners directly discharge the heat generated by servers and air conditioners themselves into the atmosphere, resulting in a large amount of energy waste. As the country pays more and more attention to energy conservation and emission reduction, it is necessary to make full use of the waste heat generated by the data center industry.

[0003] However, adding a waste heat recovery device poses a serious challenge to the cooling stability of the data center. If the system is not well controlled, it will not only fail to recover the waste heat, but will also greatly reduce the cooling reliability.

[0004] Therefore, it is very necessary to propose a data center air conditioner and its operation control method to address the phenomenon of heat waste in the data center, which can increase system stability while meeting the needs of recovering waste heat. Summary of the invention

[0005] The purpose of the present invention is to provide a data center air conditioner with waste heat recovery function and an operation control method thereof, aiming to address the phenomenon of heat waste in the data center and to achieve the goal of increasing system stability while recovering waste heat.

[0006] To achieve the above-mentioned purpose, the present invention adopts a data center air conditioner with waste heat recovery function, comprising a waste heat recovery module and two groups of refrigeration modules, the two groups of refrigeration modules are respectively connected to the waste heat recovery module, and the two groups of refrigeration modules are symmetrically arranged;

[0007] The waste heat recovery module includes a plate heat exchanger, a two-way regulating valve, a water flow sensor, a water inlet temperature sensor and a water outlet temperature sensor. The plate heat exchanger has a water side inlet and a water side outlet. The two groups of refrigeration modules are respectively connected to the plate heat exchanger. The water side inlet is respectively provided with the water flow sensor and the water inlet temperature sensor, and the water side outlet is respectively provided with the two-way regulating valve and the water outlet temperature sensor.

[0008] Wherein, the plate heat exchanger also has a primary heat exchange outlet, a primary heat exchange inlet, a secondary heat exchange outlet and a secondary heat exchange inlet.

[0009] Wherein, the refrigeration module includes a compressor, a first three-way valve, a second three-way valve, a condenser, a liquid storage tank, a fluorine pump, an expansion valve, an evaporator, a first one-way valve, a second one-way valve, a third one-way valve, a fourth one-way valve, a fifth one-way valve and a sixth one-way valve, the compressor is respectively connected to the evaporator, the condenser and the plate heat exchanger, the liquid storage tank is respectively connected to the condenser, the plate heat exchanger and the fluorine pump, the fluorine pump is connected to the evaporator, the first three-way valve is arranged between the condenser, the compressor and the plate heat exchanger, the second three-way valve is arranged between the first three-way valve, the condenser and the liquid storage tank, the expansion valve is arranged between the fluorine pump and the evaporator, the first one-way valve and the sixth one-way valve are respectively arranged at the compressor, the fourth one-way valve and the fifth one-way valve are respectively arranged at the fluorine pump, the second one-way valve is arranged at the plate heat exchanger, and the third one-way valve is arranged at the condenser.

[0010] Wherein, the first three-way valve and the second three-way valve both have an inlet A, an outlet B and an outlet C.

[0011] The present invention also provides an operation control method for a data center air conditioner with a waste heat recovery function, which controls the operation of the corresponding refrigeration module according to the conditions for each group of refrigeration modules to enter and exit waste heat recovery;

[0012] The first group of refrigeration modules enter the waste heat recovery judgment condition:

[0013] T w-out ≤ target value °C, the refrigeration module in the first group has a refrigeration demand;

[0014] After the refrigeration module of the first group enters the residual heat recovery state, the operation mode is determined according to the temperature difference value ΔT1:

[0015] ΔT1<8°C, the refrigeration module of the first group is in the compressor mode;

[0016] ΔT1≥8°C, the refrigeration module of the first group is in the fluorine pump mode;

[0017] The first group of refrigeration module exit waste heat recovery judgment conditions are:

[0018] The second group of refrigeration modules have exited waste heat recovery and T w-out ≤ target value ℃ + 5℃;

[0019] The second group of refrigeration modules enter the waste heat recovery judgment condition:

[0020] The refrigeration modules of the first group are in a waste heat recovery state and the refrigeration modules of the second group have a refrigeration demand;

[0021] After the refrigeration module of the second group enters the residual heat recovery state, it directly enters the compressor mode state;

[0022] The second group of refrigeration modules exit the waste heat recovery judgment condition is:

[0023] The opening of the two-way regulating valve has risen to the maximum allowable value and T w-out ≤ target value ℃ + 5℃;

[0024] The outlet water temperature of the plate heat exchanger 15 is T w-out , the water inlet temperature of the plate heat exchanger 15 is T w-in , the return air temperature is T r , temperature difference ΔT1 = return air temperature T r - The water inlet temperature T of the plate heat exchanger 15 w-in .

[0025] Among them, when entering the waste heat recovery state: the inlet A and outlet B of the first three-way valve are connected, and the inlet A and outlet C are disconnected to judge and adjust;

[0026] When exiting the waste heat recovery state: the inlet A and outlet B of the first three-way valve are disconnected, and the inlet A and outlet C are adjusted;

[0027] When the condensing pressure is higher than the target value: the inlet A and outlet B of the second three-way valve are connected, and the inlet A and outlet C are disconnected to judge and adjust;

[0028] When the condensing pressure is lower than the target value: the inlet A and outlet B of the second three-way valve are disconnected, and the inlet A and outlet C passages are judged and adjusted.

[0029] In the waste heat recovery process, the opening of the two-way regulating valve is adjusted according to the heat dissipation demand; the adjustment method is as follows:

[0030] Calculate waste heat recovery water flow rate;

[0031] According to the water flow rate, the opening of the two-way regulating valve is adjusted to meet the flow demand.

[0032] Among them, in the step of calculating the waste heat recovery water flow rate:

[0033] The calculation method of waste heat recovery water flow is:

[0034] Water flow rate = ((return air temperature - supply air temperature) * air specific heat capacity * internal fan speed * air volume per unit speed) / ((return water temperature - supply air temperature) * water specific heat capacity).

[0035] Wherein, in the step of adjusting the opening of the two-way regulating valve to meet the flow demand according to the water flow:

[0036] If the actual water flow rate>the target water flow rate+dead zone, the opening of the two-way regulating valve is reduced;

[0037] If the actual water flow rate is less than the target water flow rate minus the dead zone, the opening of the two-way regulating valve is increased;

[0038] If the target water flow rate - dead zone < the actual water flow rate target water flow rate + dead zone, the opening of the two-way regulating valve remains unchanged.

[0039] The present invention provides a data center air conditioner with a waste heat recovery function and an operation control method thereof, through the following settings: when entering the waste heat recovery state: the inlet A and outlet B of the first three-way valve are connected, and the inlet A and outlet C are disconnected for judgment and adjustment; when exiting the waste heat recovery state: the inlet A and outlet B of the first three-way valve are disconnected, and the inlet A and outlet C are connected for judgment and adjustment; when the condensation pressure is higher than the target value: the inlet A and outlet B of the second three-way valve are connected, and the inlet A and outlet C are disconnected for judgment and adjustment; when the condensation pressure is lower than the target value: the inlet A and outlet B of the second three-way valve are disconnected, and the inlet A and outlet C are connected for judgment and adjustment; through the above-mentioned methods, in view of the phenomenon of heat waste in the data center, it is achieved to increase the stability of the system while satisfying the recovery of waste heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 It is a structural principle diagram of a data center air conditioner with waste heat recovery function according to the present invention.

[0042] Figure 2 It is a structural principle diagram of the first three-way valve and the second three-way valve of the present invention.

[0043] Figure 3 It is a structural principle diagram of the plate heat exchanger of the present invention.

[0044] Figure 4 It is a flow chart of an operation control method of a data center air conditioner with waste heat recovery function according to the present invention.

[0045] Figure 5 It is a structural principle diagram of embodiment 1 of the present invention.

[0046] Figure 6 It is a structural principle diagram of embodiment 2 of the present invention.

[0047] 1- compressor, 2- first three-way valve, 3- second three-way valve, 4- condenser, 5- liquid storage tank, 6- fluorine pump, 7- expansion valve, 8- evaporator, 9- first one-way valve, 10- second one-way valve, 11- third one-way valve, 12- fourth one-way valve, 13- fifth one-way valve, 14- sixth one-way valve, 15- plate heat exchanger, 16- two-way regulating valve, 17- water flow sensor, 18- water inlet temperature sensor, 19- water outlet temperature sensor, 20- water side inlet, 21- primary heat exchange outlet, 22- primary heat exchange inlet, 23- water side outlet, 24- secondary heat exchange outlet, 25- secondary heat exchange inlet, 26- first two-way valve, 27- second two-way valve. DETAILED DESCRIPTION

[0048] Here, exemplary embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application.

[0049] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0050] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0051] See also Figure 1 to Figure 3 The present invention provides a data center air conditioner with a waste heat recovery function, comprising a waste heat recovery module and two groups of refrigeration modules, the two groups of refrigeration modules are respectively connected to the waste heat recovery module, and the two groups of refrigeration modules are symmetrically arranged;

[0052] The waste heat recovery module includes a plate heat exchanger 15, a two-way regulating valve 16, a water flow sensor 17, a water inlet temperature sensor 18 and a water outlet temperature sensor 19. The plate heat exchanger 15 has a water side inlet 20 and a water side outlet 23. The two groups of refrigeration modules are respectively connected to the plate heat exchanger 15. The water flow sensor 17 and the water inlet temperature sensor 18 are respectively provided at the water side inlet 20, and the two-way regulating valve 16 and the water outlet temperature sensor 19 are respectively provided at the water side outlet 23.

[0053] Furthermore, the plate heat exchanger 15 also has a primary heat exchange outlet 21 , a primary heat exchange inlet 22 , a secondary heat exchange outlet 24 and a secondary heat exchange inlet 25 .

[0054] In this embodiment, the first-level heat exchange outlet 21 and the first-level heat exchange inlet 22 are connected to the first group of refrigeration modules; the second-level heat exchange outlet 24 and the second-level heat exchange inlet 25 are connected to the second group of refrigeration modules; the low-temperature water in the water side inlet 20 of the plate heat exchanger 15 is first heated by the high-temperature refrigerant generated by the first group of refrigeration modules, and then heated by the high-temperature refrigerant generated by the second group of refrigeration modules. The water side outlet 23 becomes high-temperature water, thereby realizing waste heat recovery in the data center.

[0055] Further, the refrigeration module includes a compressor 1, a first three-way valve 2, a second three-way valve 3, a condenser 4, a liquid storage tank 5, a fluorine pump 6, an expansion valve 7, an evaporator 8, a first one-way valve 9, a second one-way valve 10, a third one-way valve 11, a fourth one-way valve 12, a fifth one-way valve 13 and a sixth one-way valve 14, the compressor 1 is respectively connected to the evaporator 8, the condenser 4 and the plate heat exchanger 15, the liquid storage tank 5 is respectively connected to the condenser 4, the plate heat exchanger 15 and the fluorine pump 6, the fluorine pump 6 is connected to the evaporator 8, the condenser 4, The first three-way valve 2 is arranged between the compressor 1 and the plate heat exchanger 15, the second three-way valve 3 is arranged between the first three-way valve 2, the condenser 4 and the liquid storage tank 5, the expansion valve 7 is arranged between the fluorine pump 6 and the evaporator 8, the first one-way valve 9 and the sixth one-way valve 14 are respectively arranged at the compressor 1, the fourth one-way valve 12 and the fifth one-way valve 13 are respectively arranged at the fluorine pump 6, the second one-way valve 10 is arranged at the plate heat exchanger 15, and the third one-way valve 11 is arranged at the condenser 4.

[0056] Furthermore, the first three-way valve 2 and the second three-way valve 3 both have an inlet A, an outlet B and an outlet C.

[0057] In this embodiment, the first group of refrigeration modules and the second group of refrigeration modules are connected to the waste heat recovery module respectively; wherein the refrigeration module has three operating modes:

[0058] The compressor 1 operates in the following manner: the compressor 1 is turned on, the fluorine pump 6 is turned off, and the other components operate normally.

[0059] The fluorine pump 6 operates in the following manner: the compressor 1 is turned off, the fluorine pump 6 is turned on, and other components operate normally.

[0060] The compressor 1 + the fluorine pump 6 operate in the following manner: the compressor 1 is turned on, the fluorine pump 6 is turned on, and the other components operate normally.

[0061] The low-temperature inlet water that needs to be heated passes through the water flow sensor 17, the water inlet temperature sensor 18, the water side inlet 20, the water side outlet 23, the water outlet temperature sensor 19, and the two-way regulating valve 16 in sequence to become high-temperature outlet water; the high-temperature gaseous refrigerant that needs to dissipate heat in the first group of refrigeration modules flows out from the outlet B of the first three-way valve 2 and flows into the first-stage heat exchange inlet 22 of the plate heat exchanger 15, and the normal-temperature refrigerant flowing out from the first-stage heat exchange outlet 21 of the plate heat exchanger 15 passes through the first one-way valve 9 and flows into the inlet A of the second three-way valve 3; the second group of refrigeration modules is the same as above.

[0062] See also Figure 4 The present invention also provides an operation control method for a data center air conditioner with a waste heat recovery function, which controls the operation of the corresponding refrigeration module according to the conditions for each group of refrigeration modules to enter and exit waste heat recovery;

[0063] The first group of refrigeration modules enter the waste heat recovery judgment condition:

[0064] T w-out ≤ target value °C, the refrigeration module in the first group has a refrigeration demand;

[0065] After the refrigeration module of the first group enters the residual heat recovery state, the operation mode is determined according to the temperature difference value ΔT1:

[0066] ΔT1<8°C, the refrigeration module of the first group is in the compressor mode;

[0067] ΔT1≥8°C, the refrigeration module of the first group is in the fluorine pump mode;

[0068] The first group of refrigeration module exit waste heat recovery judgment conditions are:

[0069] The second group of refrigeration modules have exited waste heat recovery and T w-out ≤ target value ℃ + 5℃;

[0070] The second group of refrigeration modules enter the waste heat recovery judgment condition:

[0071] The refrigeration modules of the first group are in a waste heat recovery state and the refrigeration modules of the second group have a refrigeration demand;

[0072] After the refrigeration module of the second group enters the waste heat recovery state, it directly enters the compressor mode state to ensure the outlet water temperature of the plate heat exchanger;

[0073] The second group of refrigeration modules exit the waste heat recovery judgment condition is:

[0074] The opening of the two-way regulating valve 16 has risen to the maximum allowable value and T w-out ≤ target value ℃ + 5℃;

[0075] The outlet water temperature of the plate heat exchanger 15 is T w-out , the water inlet temperature of the plate heat exchanger 15 is T w-in , the return air temperature is T r , temperature difference ΔT1 = return air temperature T r - The water inlet temperature T of the plate heat exchanger 15 w-in .

[0076] When each group of the refrigeration modules enters the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0077] When each group of the refrigeration modules exits the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are disconnected, and the inlet A and outlet C are judged and adjusted;

[0078] When the condensing pressure of each group of the refrigeration modules is higher than the target value: the inlet A and outlet B of the second three-way valve 3 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0079] When the condensing pressure of each group of the refrigeration modules is lower than the target value: the inlet A and outlet B of the second three-way valve 3 are disconnected, and the inlet A and outlet C are judged and adjusted.

[0080] Furthermore, during the waste heat recovery process, the opening of the two-way regulating valve is adjusted according to the heat dissipation demand; the adjustment method is as follows:

[0081] Calculate waste heat recovery water flow rate;

[0082] According to the water flow rate, the opening of the two-way regulating valve 16 is adjusted to meet the flow demand.

[0083] Furthermore, in the step of calculating the waste heat recovery water flow rate:

[0084] The calculation method of waste heat recovery water flow is:

[0085] Water flow rate = ((return air temperature - supply air temperature) * air specific heat capacity * internal fan speed * air volume per unit speed) / ((return water temperature - supply air temperature) * water specific heat capacity).

[0086] Further, in the step of adjusting the opening of the two-way regulating valve 16 to meet the flow demand according to the water flow:

[0087] If the actual water flow rate>the target water flow rate+dead zone, the opening of the two-way regulating valve 16 is reduced;

[0088] If the actual water flow rate is less than the target water flow rate minus the dead zone, the opening of the two-way regulating valve 16 is increased;

[0089] If the target water flow rate-dead zone<actual water flow rate target water flow rate+dead zone, the opening degree of the two-way regulating valve 16 remains unchanged.

[0090] In this embodiment, if Figure 4 As shown, the outlet water temperature of the plate heat exchanger 15 is T w-out , the water inlet temperature of the plate heat exchanger 15 is T w-in , the return air temperature is T r , temperature difference ΔT1 = return air temperature T r - The water inlet temperature T of the plate heat exchanger 15 w-in .

[0091] The first three-way valve 2 determines the adjustment:

[0092] When each group of the refrigeration modules enters the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0093] When each group of the refrigeration modules exits the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are disconnected, and the inlet A and outlet C passages are judged and adjusted.

[0094] The second three-way valve 3 determines the adjustment:

[0095] When the condensing pressure of each group of the refrigeration modules is higher than the target value: the inlet A and outlet B of the second three-way valve 3 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0096] When the condensing pressure of each group of the refrigeration modules is lower than the target value: the inlet A and outlet B of the second three-way valve 3 are disconnected, and the inlet A and outlet C are judged and adjusted.

[0097] The operation control method of the data center air conditioner with waste heat recovery function adopts the following method: calculate the waste heat recovery water flow rate; according to the water flow rate, adjust the opening of the two-way regulating valve 16 to meet the flow demand.

[0098] The calculation method of waste heat recovery water flow is:

[0099] Water flow rate = ((return air temperature - supply air temperature) * air specific heat capacity * internal fan speed * air volume per unit speed) / ((return water temperature - supply air temperature) * water specific heat capacity).

[0100] If the actual water flow rate>the target water flow rate+dead zone, the opening of the two-way regulating valve 16 is reduced;

[0101] If the actual water flow rate is less than the target water flow rate minus the dead zone, the opening of the two-way regulating valve 16 is increased;

[0102] If the target water flow rate-dead zone<actual water flow rate target water flow rate+dead zone, the opening degree of the two-way regulating valve 16 remains unchanged.

[0103] Example 1

[0104] like Figure 5 As shown, the second three-way valve 3 and the third one-way valve 11 are cancelled:

[0105] The first three-way valve 2 determines the adjustment:

[0106] When each group of the refrigeration modules enters the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0107] When each group of the refrigeration modules exits the waste heat recovery state: the inlet A and outlet B of the first three-way valve 2 are disconnected, and the inlet A and outlet C passages are judged and adjusted.

[0108] The second three-way valve 3 determines the adjustment:

[0109] When the condensing pressure of each group of the refrigeration modules is higher than the target value: the inlet A and outlet B of the second three-way valve 3 are connected, and the inlet A and outlet C are disconnected for judgment and adjustment;

[0110] When the condensing pressure of each group of the refrigeration modules is lower than the target value: the inlet A and outlet B of the second three-way valve 3 are disconnected, and the inlet A and outlet C are judged and adjusted.

[0111] Example 2

[0112] like Figure 6 As shown, on the basis of Example 1, the first three-way valve 2, the second three-way valve 3 and the third one-way valve 11 are cancelled, and a first two-way valve 26 and a second two-way valve 27 are added:

[0113] The first two-way valve 26 is open and the second two-way valve 27 is closed to determine the adjustment:

[0114] The corresponding refrigeration module enters a waste heat recovery state;

[0115] The first two-way valve 26 is closed, and the second two-way valve 27 is opened to judge the adjustment:

[0116] The corresponding refrigeration module exits the waste heat recovery state.

[0117] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the contents disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art that are not disclosed in the present application.

[0118] It will be appreciated that the present application is not limited to the exact construction that has been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

1. A data center air conditioner with waste heat recovery function, characterized in that: It includes a waste heat recovery module and two groups of refrigeration modules, the two groups of refrigeration modules are respectively connected to the waste heat recovery module, and the two groups of refrigeration modules are symmetrically arranged; The waste heat recovery module includes a plate heat exchanger, a two-way regulating valve, a water flow sensor, a water inlet temperature sensor and a water outlet temperature sensor. The plate heat exchanger has a water side inlet and a water side outlet. The two groups of refrigeration modules are respectively connected to the plate heat exchanger. The water side inlet is respectively provided with the water flow sensor and the water inlet temperature sensor, and the water side outlet is respectively provided with the two-way regulating valve and the water outlet temperature sensor.

2. The data center air conditioner with waste heat recovery function according to claim 1, characterized in that: The plate heat exchanger also has a primary heat exchange outlet, a primary heat exchange inlet, a secondary heat exchange outlet and a secondary heat exchange inlet.

3. The data center air conditioner with waste heat recovery function as claimed in claim 2, characterized in that: The refrigeration module includes a compressor, a first three-way valve, a second three-way valve, a condenser, a liquid storage tank, a fluorine pump, an expansion valve, an evaporator, a first one-way valve, a second one-way valve, a third one-way valve, a fourth one-way valve, a fifth one-way valve and a sixth one-way valve. The compressor is connected to the evaporator, the condenser and the plate heat exchanger respectively. The liquid storage tank is connected to the condenser, the plate heat exchanger and the fluorine pump respectively. The fluorine pump is connected to the evaporator. The first three-way valve is arranged between the condenser, the compressor and the plate heat exchanger. The second three-way valve is arranged between the first three-way valve, the condenser and the liquid storage tank. The expansion valve is arranged between the fluorine pump and the evaporator. The first one-way valve and the sixth one-way valve are respectively arranged at the compressor. The fourth one-way valve and the fifth one-way valve are respectively arranged at the fluorine pump. The second one-way valve is arranged at the plate heat exchanger. The third one-way valve is arranged at the condenser.

4. The data center air conditioner with waste heat recovery function as claimed in claim 3, characterized in that: The first three-way valve and the second three-way valve each have an inlet A, an outlet B and an outlet C.

5. An operation control method for a data center air conditioner with a waste heat recovery function, applied to the data center air conditioner with a waste heat recovery function as claimed in claim 4, characterized in that: According to the conditions for each group of refrigeration modules to enter and exit waste heat recovery, control the operation of the corresponding refrigeration modules; The first group of refrigeration modules enter the waste heat recovery judgment condition: T w-out ≤ target value °C, the refrigeration module in the first group has a refrigeration demand; After the refrigeration module of the first group enters the residual heat recovery state, the operation mode is determined according to the temperature difference value ΔT1: ΔT1<8°C, the refrigeration module of the first group is in the compressor mode; ΔT1≥8°C, the refrigeration module of the first group is in the fluorine pump mode; The first group of refrigeration module exit waste heat recovery judgment conditions are: The second group of refrigeration modules have exited waste heat recovery and T w-out ≤ target value ℃ + 5℃; The second group of refrigeration modules enter the waste heat recovery judgment condition: The refrigeration modules of the first group are in a waste heat recovery state and the refrigeration modules of the second group have a refrigeration demand; After the refrigeration module of the second group enters the residual heat recovery state, it directly enters the compressor mode state; The second group of refrigeration modules exit the waste heat recovery judgment condition is: The opening of the two-way regulating valve has risen to the maximum allowable value and T w-out ≤ target value ℃ + 5℃; The outlet water temperature of the plate heat exchanger 15 is T w-out , the water inlet temperature of the plate heat exchanger 15 is T w-in , the return air temperature is T r , temperature difference ΔT1 = return air temperature T r - The water inlet temperature T of the plate heat exchanger 15 w-in .

6. The operation control method of the data center air conditioner with waste heat recovery function according to claim 5, characterized in that: When entering the waste heat recovery state: the inlet A and outlet B of the first three-way valve are connected, and the inlet A and outlet C are disconnected for judgment and adjustment; When exiting the waste heat recovery state: the inlet A and outlet B of the first three-way valve are disconnected, and the inlet A and outlet C are adjusted; When the condensing pressure is higher than the target value: the inlet A and outlet B of the second three-way valve are connected, and the inlet A and outlet C are disconnected to judge and adjust; When the condensing pressure is lower than the target value: the inlet A and outlet B of the second three-way valve are disconnected, and the inlet A and outlet C passages are judged and adjusted.

7. The operation control method of the data center air conditioner with waste heat recovery function according to claim 6, characterized in that: During the waste heat recovery process, the opening of the two-way regulating valve is adjusted according to the heat dissipation demand; the adjustment method is as follows: Calculate waste heat recovery water flow rate; According to the water flow rate, the opening of the two-way regulating valve is adjusted to meet the flow demand.

8. The operation control method of the data center air conditioner with waste heat recovery function according to claim 7, characterized in that: In the steps of calculating the waste heat recovery water flow rate: The calculation method of waste heat recovery water flow is: Water flow rate = ((return air temperature - supply air temperature) * air specific heat capacity * internal fan speed * air volume per unit speed) / ((return water temperature - supply air temperature) * water specific heat capacity).

9. The operation control method of the data center air conditioner with waste heat recovery function according to claim 8, characterized in that: In the step of adjusting the opening of the two-way regulating valve to meet the flow demand according to the water flow: If the actual water flow rate>the target water flow rate+dead zone, the opening of the two-way regulating valve is reduced; If the actual water flow rate is less than the target water flow rate minus the dead zone, the opening of the two-way regulating valve is increased; If the target water flow rate - dead zone < the actual water flow rate target water flow rate + dead zone, the opening of the two-way regulating valve remains unchanged.

Images