A computer room air conditioning energy-saving transformation system and control method thereof

Abstract

The present invention relates to a computer room air conditioning energy-saving transformation system and a control method thereof, the system comprises a compressor, a condenser, a throttling device, and an evaporator, and further comprises: a compressor bypass pipeline connected between the evaporator and the condenser; a refrigerant pump and a refrigerant pump bypass pipeline connected between the condenser and the throttling device; a detection unit, comprising a first detector for detecting an outdoor ambient temperature and a second detector and a third detector for detecting an inlet pressure and an outlet pressure of the refrigerant pump respectively; a control unit connected in communication with the detection unit to control the start and stop of the compressor and the refrigerant pump according to the outdoor ambient temperature, and to control the operating speed of the refrigerant pump and the opening degree of the throttling device according to the inlet pressure and the outlet pressure of the refrigerant pump. The system can solve the problem of reliability and stable operation of the device caused by the instability of the inlet and outlet pressure of the refrigerant pump during the operation of the refrigerant pump by controlling the inlet and outlet pressure difference of the refrigerant pump.

Description

Technical Field

[0001] The present invention relates to the field of refrigeration technology, and more specifically to a computer room air conditioning energy-saving transformation system and a control method thereof. Background Art

[0002] With the rapid development of modern information technology, data centers and communication rooms have become widely popular, and the energy consumption problem of communication companies has become increasingly prominent. Under the guidance of the national energy conservation and emission reduction policy, major operators and companies are trying their best to improve the energy efficiency of data centers and reduce electricity consumption when expanding their businesses.

[0003] As a special place that needs to be cooled all year round, the data center room needs the matching computer room precision air conditioning equipment to provide continuous, stable and reliable cooling, which also brings huge power consumption of computer room precision air conditioning. At present, most computer room air conditioners still use conventional mechanical refrigeration to provide cooling for data center rooms, which consumes too much power.

[0004] Therefore, there is an urgent need to provide a design and implementation method for energy-saving transformation of conventional computer room air-conditioning systems, so as to reduce the power consumption of computer room air-conditioning by utilizing outdoor natural cold sources, and solve the abnormal problems that occur in the application process of existing energy-saving transformed air-conditioning by optimizing the control logic of the unit after design, mainly the reliability and stable operation of the device caused by the unstable inlet and outlet pressure difference of the refrigerant pump during operation. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a computer room air conditioning energy-saving transformation system and a control method thereof in view of the above-mentioned defects of the prior art.

[0006] The technical solution adopted by the present invention to solve the technical problem is: constructing an energy-saving transformation system for a computer room air conditioner, including a compressor, a condenser, a throttling device, and an evaporator connected in sequence to form a circulation loop; and also including:

[0007] a compressor bypass line connected between the outlet of the evaporator and the inlet of the condenser for selectively bypassing the compressor;

[0008] a refrigerant pump connected between the outlet of the condenser and the inlet of the throttling device;

[0009] a refrigerant pump bypass line connected between the outlet of the condenser and the inlet of the throttling device for selectively bypassing the refrigerant pump;

[0010] A detection unit, the detection unit comprising a first detector for detecting an outdoor ambient temperature T, and a second detector and a third detector for detecting an inlet pressure P1 and an outlet pressure P2 of the refrigerant pump, respectively;

[0011] A control unit is communicatively connected with the detection unit to control the start and stop of the compressor and the refrigerant pump according to the outdoor ambient temperature T, and to control the operating speed of the refrigerant pump and the opening degree of the throttling device according to the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump.

[0012] In some embodiments, the computer room air conditioning energy-saving transformation system further includes a liquid storage tank connected between the outlet of the condenser and the inlet of the refrigerant pump, and a first control valve group for bypassing the refrigerant pump or the refrigerant pump bypass pipeline;

[0013] The liquid storage tank is connected in series with the refrigerant pump and then connected in parallel with the refrigerant pump bypass pipeline;

[0014] The first control valve group includes a first one-way valve and a second one-way valve;

[0015] The second one-way valve is arranged on the refrigerant pump bypass pipeline, and the second one-way valve is configured to conduct one-way from the outlet of the condenser to the inlet of the throttling device;

[0016] The first one-way valve is connected in series with the refrigerant pump and the liquid storage tank and then connected in parallel with the refrigerant pump bypass pipeline. The flow direction of the first one-way valve is consistent with that of the second one-way valve.

[0017] In some embodiments, the computer room air conditioning energy-saving transformation system further includes a second control valve group for bypassing the compressor or the compressor bypass pipeline, and the second control valve group includes a third check valve and a fourth check valve;

[0018] The fourth one-way valve is arranged on the compressor bypass pipeline, and the fourth one-way valve is configured to conduct one-way from the outlet of the evaporator to the inlet of the condenser;

[0019] The third one-way valve is connected in series with the compressor and then in parallel with the compressor bypass pipeline, and the flow direction of the third one-way valve is consistent with that of the fourth one-way valve.

[0020] In some embodiments, the second control valve group further includes a solenoid valve, which is connected in series with the compressor and the third one-way valve and then connected in parallel with the compressor bypass pipeline;

[0021] The control unit is in communication connection with the solenoid valve to control the solenoid valve to be opened or closed.

[0022] In some embodiments, the condenser includes a condenser heat exchange coil and an outdoor fan for supplying air to the condenser heat exchange coil, and the inlet and outlet of the condenser heat exchange coil are respectively connected to the compressor and the refrigerant pump;

[0023] The evaporator comprises an evaporator heat exchange coil and an indoor fan for supplying air to the evaporator heat exchange coil. The inlet and outlet of the evaporator heat exchange coil are respectively connected to the throttling device and the compressor.

[0024] In some embodiments, the detection unit further includes a fourth detector for detecting a condensation pressure value P3 in the condenser;

[0025] The control unit is in communication connection with the outdoor fan to control the operating speed of the outdoor fan according to the condensing pressure value P3.

[0026] In some embodiments, the control unit includes a first controller, a second controller, and a third controller;

[0027] The first controller is in communication connection with the throttling device and the indoor fan;

[0028] The second controller is in communication connection with the outdoor fan and the fourth detector;

[0029] The third controller is communicatively connected with the first detector, the second detector, the third detector, and the refrigerant pump.

[0030] The present invention also provides a control method for a computer room air conditioning energy-saving transformation system, the control method comprising the following steps:

[0031] S1: Collecting the outdoor ambient temperature T, and controlling the start and stop of the compressor and the refrigerant pump according to the outdoor ambient temperature T;

[0032] S2: When the refrigerant pump is started, the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump are collected, and the opening degree of the throttling device and the operating speed of the refrigerant pump are controlled according to the inlet and outlet pressure difference ΔP of the refrigerant pump; wherein the inlet and outlet pressure difference ΔP=P2-P1.

[0033] In some embodiments, the S2 includes:

[0034] S21: Obtaining a target pressure difference value ΔP of the refrigerant pump opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max , identifying the range of the inlet and outlet pressure difference ΔP;

[0035] S22: When the inlet and outlet pressure difference ΔP satisfies ΔPmin ≤ΔP≤ΔP opt When it is, control the refrigerant pump to increase its operating speed;

[0036] S23: When the inlet and outlet pressure difference ΔP satisfies ΔP < ΔP min , control the refrigerant pump to increase its operating speed, and control the opening degree value of the throttling device not to increase anymore;

[0037] S24: When the inlet and outlet pressure difference ΔP satisfies ΔP > ΔP max When it is, control the refrigerant pump to decrease its operating speed, and control the opening degree value of the throttling device not to decrease anymore.

[0038] In some embodiments, the control method further includes:

[0039] S3: When the system starts, collect the condensation pressure value P3 in the condenser, and control the operating speed of the outdoor fan according to the condensation pressure value P3;

[0040] The S3 includes:

[0041] S31: Obtain the target condensation pressure value Ps of the condenser, and identify the range of the condensation pressure value P3;

[0042] S32: When the condensation pressure value P3 satisfies P3 < Ps, control the outdoor fan to decrease its operating speed;

[0043] S33: When the condensation pressure value P3 satisfies P3 ≥ Ps, control the outdoor fan to increase its operating speed.

[0044] Implementing the present invention has at least the following beneficial effects: By transforming the existing computer room air conditioning system, the core components of the original computer room air conditioning system (i.e., the compressor, condenser, throttling device, and evaporator) are kept unchanged, enabling the transformed system to make full use of the natural cold source outdoors, allowing it to achieve multiple different refrigeration cycle circuits, reducing the power consumption of the computer room air conditioner, and achieving the purpose of energy conservation. In addition, by controlling the inlet and outlet pressure difference of the refrigerant pump, the present invention can solve the problems of the reliability and stable operation of the device caused by the unstable inlet and outlet pressure difference during the operation of the refrigerant pump, ensuring the stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0046] Figure 1 is a schematic structural diagram of the energy-saving transformation system of the computer room air conditioner in the first embodiment of the present invention;

[0047] Figure 2is a structural schematic diagram of a computer room air conditioning energy-saving transformation system in a second embodiment of the present invention;

[0048] Figure 3 It is a structural diagram of a computer room air conditioning system in the prior art. DETAILED DESCRIPTION

[0049] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0050] Figure 3 The figure shows a computer room air conditioning system in the prior art, which includes a compressor 10, a condenser 20, a throttling device 30, and an evaporator 40 connected in sequence to form a circulation loop. The refrigerant absorbs indoor heat and evaporates in the indoor evaporator 40, evaporates into superheated refrigerant vapor and enters the compressor 10, is compressed by the compressor 10, enters the outdoor condenser 20 for condensation and heat release, condenses into a supercooled refrigerant liquid and enters the room, is throttled and depressurized by the throttling device 30, and enters the evaporator 40 for heat absorption and evaporation, and the cycle is repeated to achieve indoor cooling and temperature reduction.

[0051] Figure 1 The figure shows the energy-saving transformation system of the computer room air conditioner in the first embodiment of the present invention. By transforming the existing computer room air conditioner system, the core components of the original computer room air conditioner system (i.e., the compressor 10, the condenser 20, the throttling device 30, and the evaporator 40) are retained unchanged. Only by making design changes to the pipelines of the original computer room air conditioner system, a refrigerant pump power module is added between the outlet of the condenser 20 and the inlet of the throttling device 30, and a compressor bypass pipeline 11 for selectively bypassing the compressor 10 is added between the outlet of the evaporator 40 and the inlet of the condenser 20, so that the core components of the original computer room air conditioner system can be retained to the greatest extent, and the transformed system can make full use of the outdoor natural cold source, realize a variety of different refrigeration cycle modes, reduce the power consumption of the computer room air conditioner, and achieve the purpose of energy saving.

[0052] According to the different installation positions of various components, the computer room air conditioning energy-saving transformation system of the present invention can be divided into an indoor part and an outdoor part, wherein the indoor part mainly includes a throttling device 30 and an evaporator 40, and the outdoor part mainly includes a compressor 10, a condenser 20, and a refrigerant pump power module.

[0053] In some embodiments, the condenser 20 may include a condenser heat exchange coil 21 and an outdoor fan 22 for supplying air to the condenser heat exchange coil 21, and the inlet and outlet of the condenser heat exchange coil 21 are respectively connected to the compressor 10 and the refrigerant pump 20. The evaporator 40 may include an evaporator heat exchange coil 41 and an indoor fan 42 for supplying air to the evaporator heat exchange coil 41, and the inlet and outlet of the evaporator heat exchange coil 41 are respectively connected to the throttling device 30 and the compressor 10.

[0054] In some embodiments, the refrigerant pump power module may include a liquid storage tank 52 for storing refrigerant, a refrigerant pump 50 for pressurizing the refrigerant, and a refrigerant pump bypass line 51 for selectively bypassing the refrigerant pump 50 and the liquid storage tank 52. The refrigerant pump 50 and the liquid storage tank 52 are connected in series and then connected in parallel with the refrigerant pump bypass line 51. The refrigerant pump 50 can be a fluorine pump using freon as refrigerant, such as R22, R410A, R134A or R407C, etc., which has good insulation and is in a gaseous state under normal pressure. Even if it leaks, there will be no safety hazard of short circuit. The liquid storage tank 52 can be arranged between the outlet of the condenser 20 and the inlet of the refrigerant pump 50 to ensure that what enters the refrigerant pump 50 is refrigerant liquid.

[0055] In some embodiments, the computer room air conditioning energy-saving transformation system may further include a first control valve group for bypassing the refrigerant pump 50 or the refrigerant pump bypass pipeline 51 , and a second control valve group for bypassing the compressor 10 or the compressor bypass pipeline 11 .

[0056] In some embodiments, the first control valve group may include a first one-way valve 53 and a second one-way valve 54. The second one-way valve 54 is arranged in series on the refrigerant pump bypass line 51, and the second one-way valve 54 is configured to be unidirectionally conducted in the direction from the outlet of the condenser 20 to the inlet of the throttling device 30. The first one-way valve 53 is connected in series with the refrigerant pump 50 and the liquid storage tank 52, and then connected in parallel with the refrigerant pump bypass line 51. Preferably, the flow direction of the first one-way valve 53 is consistent with that of the second one-way valve 54, which can effectively prevent the occurrence of cross-flow. In this embodiment, the first one-way valve 53 is arranged at the outlet end of the refrigerant pump 50. In other embodiments, the first one-way valve 53 may also be arranged at the inlet end of the liquid storage tank 52, or may also be arranged between the liquid storage tank 52 and the refrigerant pump 50.

[0057] In some embodiments, the second control valve group may include a third one-way valve 12 and a fourth one-way valve 13. The fourth one-way valve 13 is arranged in series on the compressor bypass line 11, and the fourth one-way valve 13 is configured to be unidirectionally conducted in the direction from the outlet of the evaporator 40 to the inlet of the condenser 20. The third one-way valve 12 is connected in series with the compressor 10 and then connected in parallel with the compressor bypass line 11. Preferably, the flow directions of the third one-way valve 12 and the fourth one-way valve 13 are consistent, which can effectively prevent the occurrence of cross-flow. In this embodiment, the third one-way valve 12 is arranged at the outlet end of the compressor 10. In other embodiments, the third one-way valve 12 can also be arranged at the inlet end of the compressor 10.

[0058] The specific transformation and implementation method of the computer room air conditioning energy-saving transformation system includes the following steps:

[0059] A third one-way valve 12 is added at the outlet of the compressor 10, a compressor bypass line 11 is added between the outlet of the evaporator 40 and the inlet of the condenser 20, and a fourth one-way valve 13 is connected in series to the compressor bypass line 11;

[0060] A refrigerant pump power module is added between the outlet of the condenser 20 and the inlet of the throttling device 30 .

[0061] The computer room air conditioning energy-saving transformation system can realize at least the following three operating circuits:

[0062] The first operating circuit: the refrigerant flows through the compressor bypass pipe 11, the condenser 20, the liquid storage tank 52, the refrigerant pump 50, the throttling device 30, and the evaporator 40 in sequence to form a circulation circuit. At this time, the refrigerant pump 50 is started and the compressor 10 is stopped, making full use of the outdoor natural cold source, and using the refrigerant pump 50 instead of the compressor 10 to provide power for the system cycle. Since the power of the refrigerant pump 50 is much smaller than the power of the compressor 10, the power consumption of the computer room air conditioner can be significantly reduced, which has a significant energy-saving effect.

[0063] The second operating circuit: the refrigerant flows through the compressor 10, the condenser 20, the refrigerant pump bypass line 51, the throttling device 30, and the evaporator 40 in sequence to form a circulation circuit. At this time, the refrigerant pump 50 is stopped and the compressor 10 is started to provide power for the system refrigeration operation.

[0064] The third operating circuit: the refrigerant flows through the compressor 10, the condenser 20, the liquid storage tank 52, the refrigerant pump 50, the throttling device 30, and the evaporator 40 in sequence to form a circulation circuit. At this time, the refrigerant pump 50 and the compressor 10 are both started, and the outdoor natural cold source is partially utilized. The refrigerant pump 50 can compensate for the circulation power of the refrigerant in the system, reduce the pressure loss of the refrigerant during the circulation process, and make the compressor 10 work under the best working conditions, reduce the energy consumption of the compressor, and improve the refrigeration efficiency, which has a certain energy-saving effect.

[0065] The user can select a suitable operating circuit according to different application conditions. For example, the user can select a suitable operating circuit according to the outdoor ambient temperature conditions.

[0066] In some embodiments, the energy-saving transformation system for the machine room air conditioner may further include a detection unit and a control unit 60 that is communicatively connected to the detection unit. In some embodiments, the detection unit may include a first detector 71 for detecting the outdoor ambient temperature T, and a second detector 72 and a third detector 73 for respectively detecting the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump 50. The control unit 60 is communicatively connected to the refrigerant pump 50, the compressor 10, and the throttling device 30, respectively, and may control the start and stop of the refrigerant pump 50 and the compressor 10 according to the outdoor ambient temperature T, and control the operating speed of the refrigerant pump 50 and the opening degree of the throttling device 30 according to the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump 50. In some embodiments, the detection unit may further include a fourth detector 74 for detecting the condensing pressure value P3 (usually the outlet pressure value of the condenser heat exchange coil 21) in the condenser 20, and the control unit 60 may also be communicatively connected to the outdoor fan 22, and may control the operating speed of the outdoor fan 22 according to the condensing pressure value P3. The first detector 71 may be a temperature sensor, and the second detector 72 , the third detector 73 , and the fourth detector 74 may all be pressure sensors.

[0067] The control unit 60 can also be connected to the indoor fan 42 for communication. The control unit 60 can be pre-set with a speed range of the indoor fan 42, and the indoor fan 42 can automatically adjust its speed within the speed range.

[0068] The control unit 60 in this embodiment may include a first controller 61, a second controller 62, and a third controller 63. The first controller 61, the second controller 62, and the third controller 63 may be made on a circuit board respectively, and the functions of the control unit 60 are distributed among the three controllers, so as to reduce the workload of each controller and improve the working efficiency. Specifically, the first controller 61 may be connected to the throttling device 30 and the indoor fan 42 respectively, the second controller 62 may be connected to the outdoor fan 22 and the fourth detector 74 respectively, and the third controller 63 may be connected to the first detector 71, the second detector 72, the third detector 73, and the refrigerant pump 50 respectively. It can be understood that in other embodiments, the functions of the control unit 60 may also be integrated into one controller, or the functions of the control unit 60 may also be distributed among two, four or more controllers.

[0069] The control method of the computer room air conditioning energy-saving transformation system may include the following steps:

[0070] S1: Collecting the outdoor ambient temperature T, and controlling the start and stop of the compressor 10 and the refrigerant pump 50 according to the outdoor ambient temperature T;

[0071] S2: When the refrigerant pump 50 is started (i.e., the first operating circuit and the third operating circuit), the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump 50 are collected, and the opening degree of the throttling device 30 and the operating speed of the refrigerant pump 50 are controlled according to the inlet and outlet pressure difference ΔP (ΔP=P2-P1) of the refrigerant pump 50.

[0072] Specifically, step S1 may include:

[0073] S11: When the outdoor ambient temperature T meets the first switching condition, the refrigerant pump 50 is controlled to start and the compressor 1 is stopped, so that the computer room air conditioning energy-saving transformation system operates in the first operation loop;

[0074] S12: When the outdoor ambient temperature T meets the second switching condition, the refrigerant pump 50 is controlled to stop and the compressor 10 is started, so that the computer room air conditioning energy-saving transformation system operates in the second operation loop;

[0075] S13: When the outdoor ambient temperature T satisfies the third switching condition, the refrigerant pump 50 and the compressor 10 are controlled to start simultaneously, so that the computer room air conditioning energy-saving transformation system operates in the third operation loop.

[0076] Specifically, in this embodiment, the first switching condition, the second switching condition, and the third switching condition are respectively T<Ta、T> Tb, Ta≤T≤Tb, wherein Ta and Tb are both preset temperatures.

[0077] In some embodiments, to improve the stability of system operation, step S1 may further include:

[0078] S14: When the outdoor ambient temperature T is detected as an invalid value, the refrigerant pump 50 is controlled to stop and the compressor 10 is started, so that the computer room air conditioning energy-saving transformation system operates in the second operation loop.

[0079] Specifically, in this embodiment, the third controller 63 is communicatively connected with the first detector 71, which can synchronously monitor the outdoor ambient temperature T. The third controller 63 feeds back the outdoor ambient temperature T value to the first controller 61. The first controller 61 identifies the range of the outdoor ambient temperature T by comparing the T value with Ta and Tb pre-stored therein; then, based on the identification result, the first controller 61 issues an instruction and transmits it to the third controller 63, so that the refrigerant pump 50 controlled by it starts or stops, and the first controller 61 controls the compressor 10 to start or stop.

[0080] It can be understood that in other embodiments, a suitable operating circuit can also be selected according to the indoor and outdoor temperature difference. For example, the first switching condition, the second switching condition, and the third switching condition can also be T<Tn-ΔT1、T> Tn+ΔT2, Tn-ΔT1≤T≤Tn+ΔT2. Wherein, Tn is the indoor ambient temperature, which can be collected by a temperature sensor, and ΔT1 and ΔT2 are preset temperature differences.

[0081] Step S2 may include:

[0082] S21: Obtaining the target differential pressure value ΔP of the refrigerant pump 50 opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max , identify the range of the inlet and outlet pressure difference ΔP.

[0083] Target pressure difference ΔP opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max are all preset values. In this embodiment, they are all pre-set in the first controller 61. Among them, the target pressure difference value ΔP opt The minimum pressure difference ΔP is the most suitable pressure difference between the inlet and outlet of the refrigerant pump 50 in the corresponding operating circuit (target pressure difference). Working under this target pressure difference can ensure the reliable and stable operation of the refrigerant pump 50. min , and the maximum pressure difference ΔP max They are respectively the minimum pressure difference value and the maximum pressure difference value of the inlet and outlet of the refrigerant pump 50 in the corresponding operating circuit, so as to avoid the problem that the refrigerant is difficult to circulate due to the small pressure difference value between the inlet and outlet of the refrigerant pump 50, and cavitation occurs during the circulation process, causing damage to the refrigerant pump; or the problem that the refrigerant pump is overloaded and easily damaged due to the large pressure difference value between the inlet and outlet of the refrigerant pump 50.

[0084] Target pressure difference ΔP opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max It can be flexibly set according to different application environments and operating loops. For example, in this embodiment, the target pressure difference value ΔP in the first operating loop is opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max Set as ΔP opt1 , ΔP min1 , and ΔP max1 , the target pressure difference value ΔP in the third operating circuit opt , minimum pressure difference ΔP min , and the maximum pressure difference ΔP max Set as ΔP opt3, ΔP min3 , and ΔP max3 In this embodiment, the target pressure difference value ΔP opt3 <P opt1 , ΔP min3 =ΔP min1 , ΔP max3 <ΔP max1 .

[0085] In this embodiment, the third controller 63 is connected to the second detector 72 and the third detector 73 for communication, and can synchronously monitor the inlet and outlet pressure difference ΔP (ΔP=P2-P1) of the refrigerant pump 50. The third controller 63 feeds back the ΔP value to the first controller 61, and the first controller 61 compares ΔP with ΔP. opt , ΔP min , ΔP max , identify the range of the inlet and outlet pressure difference ΔP.

[0086] S22: When the inlet and outlet pressure difference ΔP of the refrigerant pump 50 satisfies ΔP min ≤ΔP≤ΔP opt When the refrigerant pump 50 is controlled to increase the operating speed.

[0087] Specifically, in this embodiment, ΔP min ≤ΔP≤ΔP opt When the first controller 61 issues a command to the third controller 63, the third controller 63 controls the refrigerant pump 50 to increase the operating speed, so that the inlet and outlet pressure difference of the refrigerant pump 50 moves toward the target pressure difference value ΔP opt Close to ensure the stable operation of the unit. At this time, the opening degree of the throttling device 30 is suitable, and there is no need to increase the relevant control, and it can be automatically adjusted.

[0088] S23: When the inlet and outlet pressure difference ΔP of the refrigerant pump 50 satisfies ΔP<ΔP min , control the refrigerant pump 50 to increase the operating speed, and control the opening value of the throttling device 30 to no longer increase.

[0089] Specifically, in this embodiment, ΔP<ΔP min When the first controller 61 issues a command to the third controller 63, the third controller 63 controls the refrigerant pump 50 to increase the operating speed, so that the inlet and outlet pressure difference of the refrigerant pump 50 moves toward the target pressure difference value ΔP opt near.

[0090] In addition, in this state, since the inlet and outlet pressure difference of the refrigerant pump 50 is low, if the opening degree of the throttling device 30 is not controlled, if the opening degree of the throttling device 30 continues to increase, the inlet and outlet pressure difference of the refrigerant pump 50 will be lower, thereby causing adverse effects on the operation of the unit. Therefore, in this state, the first controller 61 will also control the opening degree of the throttling device 30 not to increase, so as to ensure the stable operation of the unit.

[0091] S24: When the inlet and outlet pressure difference ΔP of the refrigerant pump 50 satisfies ΔP>ΔP max When the refrigerant pump 50 is controlled to reduce the operating speed, the opening value of the throttling device 30 is controlled not to be reduced.

[0092] Specifically, in this embodiment, ΔP<ΔP min When the first controller 61 issues a command to the third controller 63, the third controller 63 controls the refrigerant pump 50 to reduce the operating speed, so that the inlet and outlet pressure difference of the refrigerant pump 50 moves toward the target pressure difference value ΔP opt near.

[0093] In addition, in this state, since the inlet and outlet pressure difference of the refrigerant pump 50 is relatively high, if the opening degree of the throttling device 30 is not controlled, if the opening degree of the throttling device 30 continues to decrease, the inlet and outlet pressure difference of the refrigerant pump 50 will be higher, thereby causing adverse effects on the operation of the unit. Therefore, in this state, the first controller 61 will also control the opening degree of the throttling device 30 not to decrease, thereby ensuring the stable operation of the unit.

[0094] Specifically, taking the first operating loop as an example, step S2 may include:

[0095] S21: Obtaining the target pressure difference value ΔP pre-stored in the first controller 61 opt1 , minimum pressure difference ΔP min1 , and the maximum pressure difference ΔP max1 , identify the range of the inlet and outlet pressure difference ΔP;

[0096] S22: When the inlet and outlet pressure difference ΔP of the refrigerant pump 50 satisfies ΔP min1 ≤ΔP≤ΔP opt1 When the first controller 61 issues a command to the third controller 63, the third controller 63 controls the refrigerant pump 50 to increase the operating speed, so that the inlet and outlet pressure difference of the refrigerant pump 50 moves toward the target pressure difference value ΔP opt near;

[0097] S23: When the inlet and outlet pressure difference ΔP of the refrigerant pump 50 satisfies ΔP<ΔP min1The first controller 61 issues an instruction, which is transmitted to the third controller 63, to increase the operating speed of the refrigerant pump 50 it controls. And in this state, the first controller 61 will also control the opening degree value of the throttling device 30 not to increase, so that the pressure difference between the inlet and outlet of the refrigerant pump 50 approaches the target pressure difference ΔP opt1 to ensure the stable operation of the unit;

[0098] S24: When the pressure difference ΔP between the inlet and outlet of the refrigerant pump 50 satisfies ΔP > ΔP max1 the first controller 61 issues an instruction, which is transmitted to the third controller 63, to decrease the operating speed of the refrigerant pump 50 it controls. And in this state, the first controller 61 will also control the opening degree value of the throttling device 30 not to decrease, so that the pressure difference between the inlet and outlet of the refrigerant pump 50 approaches the target pressure difference ΔP opt1 to ensure the stable operation of the unit.

[0099] On this basis, to ensure that the unit can achieve the best energy-saving effect and stable operation of the unit when operating in the corresponding operating circuit, the control method may further include:

[0100] S3: When the system starts, collect the condensing pressure value P3 in the condenser 20, and control the operating speed of the outdoor fan 22 according to the condensing pressure value P3.

[0101] Specifically, in this embodiment, the first controller 61 synchronously monitors the condensing pressure value P3 in the outdoor condenser 20 (i.e., the feedback value P3 of the fourth detector 74), and the condensing pressure value P3 is the outlet pressure value of the condenser heat exchange coil 21 in this embodiment.

[0102] Specifically, step S3 may include:

[0103] S31: Obtain the target condensing pressure value Ps of the condenser 20 and identify the range of the condensing pressure value P3.

[0104] Specifically, in this embodiment, by comparing the condensing pressure value P3 with the target condensing pressure value Ps preset in the first controller 61, the range of the condensing pressure value P3 is identified.

[0105] The target condensing pressure value Ps can be flexibly set according to different application environments and operating circuits. For example, in this embodiment, the target condensing pressure values Ps in the first operating circuit, the second operating circuit, and the third operating circuit can be set as Ps1, Ps2, and Ps3 respectively, and in this embodiment, Ps2 > Ps3 > Ps1.

[0106] S32: When the condensing pressure value P3 satisfies P3 < Ps, control the outdoor fan 22 to decrease the operating speed.

[0107] Specifically, when P3 < Ps, the first controller 61 issues an instruction to the second controller 62 to control the outdoor fan 22 to reduce its operating speed. This can not only effectively reduce the consumed electric power, but also make the condensation pressure value P3 approach the preset target condensation pressure value Ps (the target condensation pressure value under the corresponding operating loop), ensuring the stable operation of the unit.

[0108] S33: When the condensation pressure value P3 satisfies P3 ≥ Ps, control the outdoor fan 22 to increase its operating speed.

[0109] Specifically, when P3 ≥ Ps, the first controller 61 issues an instruction to the second controller 62 to control the outdoor fan 22 to increase its operating speed, making the condensation pressure value P3 approach the preset target condensation pressure value Ps (the target condensation pressure value under the corresponding operating loop), and making the unit operate more stably and reliably.

[0110] Figure 2 The figure shows an energy-saving renovation system for a computer room air conditioner in the second embodiment of the present invention. Compared with the first embodiment, the second control valve group in this embodiment further includes an electric valve 14, which is connected in series with the compressor 10 and the third one-way valve 12 and is in parallel with the compressor bypass pipeline 11. In this embodiment, the electric valve 14 is arranged at the inlet end of the compressor 10. In other embodiments, the electric valve 14 can also be arranged at the outlet end of the compressor 10.

[0111] Correspondingly, the control unit 60 is also communicatively connected to the electric valve 14 to control the opening or closing of the electric valve 14. Specifically, in this embodiment, the first controller 61 is communicatively connected to the electric valve 14 to control the electric valve 14 to open when executing the second and third operating loops, and to control the electric valve 14 to close in other situations (such as the first operating loop or the shutdown state).

[0112] It can be understood that the above technical features can be combined arbitrarily without limitation.

[0113] The above embodiments only represent the preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present invention; it should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can also be made, which all belong to the protection scope of the present invention; therefore, all equivalent transformations and modifications made to the scope of the claims of the present invention shall fall within the scope covered by the claims of the present invention.

Claims

1. A computer room air conditioning energy-saving transformation system, comprising a compressor (10), a condenser (20), a throttling device (30), and an evaporator (40) connected in sequence to form a circulation loop, characterized in that: Also includes: a compressor bypass line (11) connected between the outlet of the evaporator (40) and the inlet of the condenser (20) for selectively bypassing the compressor (10); a refrigerant pump (50) connected between the outlet of the condenser (20) and the inlet of the throttling device (30); a refrigerant pump bypass pipeline (51) connected between the outlet of the condenser (20) and the inlet of the throttling device (30) for selectively bypassing the refrigerant pump (50); A detection unit, the detection unit comprising a first detector (71) for detecting an outdoor ambient temperature T, and a second detector (72) and a third detector (73) for respectively detecting an inlet pressure P1 and an outlet pressure P2 of the refrigerant pump (50); A control unit (60), the control unit (60) being in communication connection with the detection unit to control the start and stop of the compressor (10) and the refrigerant pump (50) according to the outdoor ambient temperature T, and to control the operating speed of the refrigerant pump (50) and the opening degree of the throttling device (30) according to the inlet and outlet pressure difference ΔP of the refrigerant pump (50), wherein the inlet and outlet pressure difference ΔP= P2-P1, The control unit (60) pre-stores a target pressure difference value ΔP of the refrigerant pump (50). opt , minimum pressure difference ΔP min And the maximum pressure difference ΔP max , The control unit (60) is configured to: When the inlet and outlet pressure difference ΔP satisfies ΔP min ≤ΔP≤ΔP opt When the refrigerant pump (50) is controlled to increase the operating speed; When the inlet and outlet pressure difference ΔP satisfies ΔP < ΔP min , controlling the refrigerant pump (50) to increase the operating speed, and controlling the opening value of the throttling device (30) to no longer increase; When the inlet and outlet pressure difference ΔP satisfies ΔP>ΔP max When the refrigerant pump (50) is controlled to reduce the operating speed, the opening value of the throttling device (30) is controlled to no longer reduce.

2. The computer room air conditioning energy-saving transformation system according to claim 1 is characterized in that: The computer room air conditioning energy-saving transformation system further comprises a liquid storage tank (52) connected between the outlet of the condenser (20) and the inlet of the refrigerant pump (50), and a first control valve group for bypassing the refrigerant pump (50) or the refrigerant pump bypass pipeline (51); The liquid storage tank (52) is connected in series with the refrigerant pump (50) and then connected in parallel with the refrigerant pump bypass pipeline (51); The first control valve group comprises a first one-way valve (53) and a second one-way valve (54); The second one-way valve (54) is arranged on the refrigerant pump bypass pipeline (51), and the second one-way valve (54) is configured to conduct one-way flow from the outlet of the condenser (20) to the inlet of the throttling device (30); The first one-way valve (53) is connected in series with the refrigerant pump (50) and the liquid storage tank (52), and then connected in parallel with the refrigerant pump bypass pipeline (51); the flow direction of the first one-way valve (53) is consistent with that of the second one-way valve (54).

3. The computer room air conditioning energy-saving transformation system according to claim 1 is characterized in that: The computer room air conditioning energy-saving transformation system further comprises a second control valve group for bypassing the compressor (10) or the compressor bypass pipeline (11), the second control valve group comprising a third check valve (12) and a fourth check valve (13); The fourth one-way valve (13) is arranged on the compressor bypass pipeline (11), and the fourth one-way valve (13) is configured to conduct one-way flow in a direction from the outlet of the evaporator (40) to the inlet of the condenser (20); The third one-way valve (12) is connected in series with the compressor (10) and then connected in parallel with the compressor bypass pipeline (11); the flow direction of the third one-way valve (12) is consistent with that of the fourth one-way valve (13).

4. The computer room air conditioning energy-saving transformation system according to claim 3 is characterized in that: The second control valve group further comprises a solenoid valve (14), wherein the solenoid valve (14) is connected in series with the compressor (10) and the third one-way valve (12), and then connected in parallel with the compressor bypass pipeline (11); The control unit (60) is communicatively connected to the solenoid valve (14) to control the solenoid valve (14) to open or close.

5. The computer room air conditioning energy-saving transformation system according to claim 1 is characterized in that: The condenser (20) comprises a condenser heat exchange coil (21) and an outdoor fan (22) for supplying air to the condenser heat exchange coil (21); an inlet and an outlet of the condenser heat exchange coil (21) are respectively connected to the compressor (10) and the refrigerant pump (50); The evaporator (40) comprises an evaporator heat exchange coil (41) and an indoor fan (42) for supplying air to the evaporator heat exchange coil (41); an inlet and an outlet of the evaporator heat exchange coil (41) are respectively connected to the throttling device (30) and the compressor (10).

6. The computer room air conditioning energy-saving transformation system according to claim 5 is characterized in that: The detection unit further comprises a fourth detector (74) for detecting a condensation pressure value P3 in the condenser (20); The control unit (60) is communicatively connected to the outdoor fan (22) to control the operating speed of the outdoor fan (22) according to the condensing pressure value P3.

7. The computer room air conditioning energy-saving transformation system according to claim 6 is characterized in that: The control unit (60) comprises a first controller (61), a second controller (62), and a third controller (63); The first controller (61) is communicatively connected with the throttling device (30) and the indoor fan (42); The second controller (62) is communicatively connected with the outdoor fan (22) and the fourth detector (74); The third controller (63) is communicatively connected to the first detector (71), the second detector (72), the third detector (73), and the refrigerant pump (50).

8. A control method for a computer room air conditioning energy-saving transformation system according to any one of claims 1 to 7, characterized in that: The control method comprises the following steps: S1: collecting the outdoor ambient temperature T, and controlling the start and stop of the compressor (10) and the refrigerant pump (50) according to the outdoor ambient temperature T; S2: When the refrigerant pump (50) is started, the inlet pressure P1 and the outlet pressure P2 of the refrigerant pump (50) are collected, and according to the inlet and outlet pressure difference ΔP of the refrigerant pump (50), the opening degree of the throttling device (30) and the operating speed of the refrigerant pump (50) are controlled; wherein the inlet and outlet pressure difference ΔP = P2-P1, The S2 includes: S21: obtaining a target pressure difference value ΔPopt, a minimum pressure difference value ΔPmin, and a maximum pressure difference value ΔPmax of the refrigerant pump (50), and identifying a range of the inlet and outlet pressure difference ΔP; S22: When the inlet and outlet pressure difference ΔP satisfies ΔPmin≤ΔP≤ΔPopt, controlling the refrigerant pump (50) to increase the operating speed; S23: When the inlet and outlet pressure difference ΔP satisfies ΔP<ΔPmin, controlling the refrigerant pump (50) to increase the operating speed, and controlling the opening value of the throttling device (30) to no longer increase; S24: When the inlet and outlet pressure difference ΔP satisfies ΔP > ΔPmax, control the refrigerant pump (50) to reduce the operating speed, and control the opening degree value of the throttling device (30) not to decrease any further.

9. The control method according to claim 8, characterized in that: The control method further includes: S3: When the system starts, collect the condensation pressure value P3 in the condenser (20), and control the operating speed of the outdoor fan (22) according to the condensation pressure value P3; The S3 includes: S31: Obtain the target condensation pressure value Ps of the condenser (20), and identify the range of the condensation pressure value P3; S32: When the condensation pressure value P3 satisfies P3 < Ps, control the outdoor fan (22) to reduce the operating speed; S33: When the condensation pressure value P3 satisfies P3 ≥ Ps, control the outdoor fan (22) to increase the operating speed.

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