Fluorine pump compressor double cycle refrigeration system and control method thereof

Abstract

The application provides a fluorine pump compressor double-cycle refrigeration system and a control method thereof. The refrigeration system comprises a compressor mode driven by a compressor cycle and a fluorine pump mode driven by a fluorine pump cycle, and further comprises a first liquid storage tank. The first liquid storage tank has a liquid storage state and a liquid discharge state. Before the refrigeration system is switched from the compressor mode to the fluorine pump mode, the first liquid storage tank is in the liquid discharge state, so that liquid refrigerant in the first liquid storage tank is at least partially released and discharged into the refrigerant cycle. Before the refrigeration system is switched from the fluorine pump mode to the compressor mode, the first liquid storage tank is in the liquid storage state, so that liquid refrigerant in the refrigerant cycle is partially recovered and stored in the first liquid storage tank. The application solves the problem that the required refrigerant filling amount is different in two modes, and realizes efficient operation of the double-cycle system in two operating modes, thereby achieving energy-saving effect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of air conditioning technology, and particularly relates to a fluorine pump compressor double-cycle refrigeration system and a control method thereof. BACKGROUND

[0002] It has been proved by practice that the fluorine pump compressor double-cycle refrigeration system has a high energy efficiency ratio (EER) in seasonal cooling capacity demand throughout the year in the air conditioning system of a data center room (the compressor system is cycled to run when the air temperature is high, and the fluorine pump system is cycled to run when the air temperature is low). The running mode has obvious energy-saving advantages compared with the traditional compressor single-cycle refrigeration mode, but the double-cycle system structure is relatively complex, and some technical problems need to be improved, among which the most prominent problem is that the optimal charge amount of refrigerant required when the double-cycle system runs in the compressor mode and the fluorine pump mode has a large gap. If the charge amount of refrigerant in the system cannot be adjusted in time after the two running modes are switched, the refrigerating capacity and effect of the system during running will be affected. SUMMARY

[0003] Therefore, the present application provides a fluorine pump compressor double-cycle refrigeration system and a control method thereof, which can solve the technical problem that the optimal charge amount of refrigerant required when the fluorine pump compressor double-cycle air conditioning system runs in the compressor mode and the fluorine pump mode has a large gap, and the charge amount of refrigerant in the system cannot be adjusted in time when switching, affecting the refrigerating capacity and effect of the system during running.

[0004] In order to solve the above problems, the present application provides a fluorine pump compressor double-cycle refrigeration system, which comprises a compressor mode driven by a compressor and a fluorine pump mode driven by a fluorine pump, and further comprises a first liquid storage tank. The first liquid storage tank has a liquid storage state and a liquid discharge state. Before the refrigeration system is switched from the compressor mode to the fluorine pump mode, the first liquid storage tank is in the liquid discharge state, so as to at least partially release and discharge the liquid refrigerant in the first liquid storage tank to the refrigerant cycle. Before the refrigeration system is switched from the fluorine pump mode to the compressor mode, the first liquid storage tank is in the liquid storage state, so as to partially recover the liquid refrigerant in the refrigerant cycle and store it in the first liquid storage tank.

[0005] In some embodiments, the fluorine pump compressor double-cycle refrigeration system further comprises a condenser, a second liquid storage tank, an evaporator, a throttling element, an inlet of the condenser being in communication with an exhaust port of the compressor, an outlet of the condenser being in controllable communication with a pump inlet of the fluorine pump via the second liquid storage tank, a pump outlet of the fluorine pump being in communication with an inlet of the evaporator, an outlet of the evaporator being in communication with a suction port of the compressor and via a first pipeline with the exhaust port of the compressor, the first pipeline being provided with a first one-way valve, a one-way communication direction of the first one-way valve being from the evaporator to the condenser, the first liquid storage tank and a liquid outlet of the second liquid storage tank being in communication via a second pipeline, and the second pipeline being serially connected with the throttling element, when the first liquid storage tank is in the liquid storage state, liquid refrigerant in the second liquid storage tank being driven by the fluorine pump to partially enter the first liquid storage tank via a third pipeline.

[0006] In some embodiments, when the first liquid storage tank is in the liquid discharge state, liquid refrigerant in the first liquid storage tank is driven by the exhaust pressure of the compressor to enter the refrigerant cycle via the third pipeline.

[0007] In some embodiments, the third pipeline is serially connected with a first electromagnetic valve; a pipeline between the liquid outlet of the second liquid storage tank and the pump inlet of the fluorine pump is a fourth pipeline, the fourth pipeline being serially connected with a second electromagnetic valve, and the second pipeline being in communication with the fourth pipeline at an inlet side of the second electromagnetic valve.

[0008] In some embodiments, the first liquid storage tank is further in communication with the inlet of the condenser via a fifth pipeline, the fifth pipeline being serially connected with a third electromagnetic valve, and further comprising a sixth pipeline, a first end of the sixth pipeline being in communication with the fifth pipeline between the third electromagnetic valve and the first liquid storage tank, a second end of the sixth pipeline being in communication with a pipeline between the first electromagnetic valve and the inlet of the evaporator, and the sixth pipeline being serially connected with a fourth electromagnetic valve.

[0009] In some embodiments, the second pipeline is further serially connected with a second one-way valve, a communication direction of the second one-way valve being from the second liquid storage tank to the first liquid storage tank.

[0010] The application further provides a control method of the fluorine pump compressor double-cycle refrigeration system as described above, comprising the following steps:

[0011] obtaining a refrigeration system operation mode switching instruction;

[0012] After the switching instruction is acquired, before the fluorine pump compressor double cycle refrigeration system is switched from the current operation mode to the target operation mode according to the switching instruction, an intermediate switching mode is run to recycle part of the liquid refrigerant in the refrigerant cycle and store it in the first liquid storage tank or at least partially release the liquid refrigerant in the first liquid storage tank to the refrigerant cycle.

[0013] In some embodiments, when the current operation mode is the compressor mode and the target operation mode is the fluorine pump mode, the intermediate switching mode is a refrigerant liquid discharge mode, which at least partially releases the liquid refrigerant in the first liquid storage tank to the refrigerant cycle before controlling the refrigeration system to run in the fluorine pump mode; or when the current operation mode is the fluorine pump mode and the target operation mode is the compressor mode, the intermediate switching mode is a refrigerant liquid storage mode, which recycles part of the liquid refrigerant in the refrigerant cycle and stores it in the first liquid storage tank before controlling the refrigeration system to run in the compressor mode.

[0014] In some embodiments, when the refrigeration system runs in the compressor mode, the compressor is controlled to operate, the first electromagnetic valve and the fourth electromagnetic valve are controlled to be turned on, and the second electromagnetic valve and the third electromagnetic valve are controlled to be turned off; or,

[0015] When the refrigeration system runs in the fluorine pump mode, the fluorine pump is controlled to operate, the second electromagnetic valve is controlled to be turned on, and the first electromagnetic valve, the third electromagnetic valve, and the fourth electromagnetic valve are controlled to be turned off.

[0016] In some embodiments, when the refrigeration system runs in the refrigerant liquid discharge mode, the compressor is controlled to maintain the operating state, the third electromagnetic valve and the first electromagnetic valve are controlled to be turned on, and the fourth electromagnetic valve and the second electromagnetic valve are controlled to be turned off; or,

[0017] When the refrigeration system runs in the refrigerant liquid storage mode, the fluorine pump is controlled to maintain the operating state, the first electromagnetic valve, the second electromagnetic valve, and the third electromagnetic valve are controlled to be turned on, and the fourth electromagnetic valve is controlled to be turned off.

[0018] In some embodiments, when the refrigeration system is in the refrigerant liquid storage mode, the corresponding internal fan of the evaporator is controlled to stop running, and the length of time for which the refrigerant liquid storage mode is run is ensured to be t0, t0 = V(f1 + f2) / qf1, where V is the volume of the first liquid storage tank, q is the volume flow rate of the fluorine pump, f1 is the pipe resistance of the refrigerant flowing from the fluorine pump to the evaporator, and f2 is the pipe resistance of the refrigerant flowing from the fluorine pump to the first liquid storage tank.

[0019] In some embodiments, during the process in which the refrigeration system runs in the compressor mode, the following steps are further included:

[0020] Obtain the outlet superheat degree of the evaporator, when the obtained outlet superheat degree is higher than a set superheat degree value, control the first electromagnetic valve to be turned on and the fourth electromagnetic valve to be cut off; when the outlet superheat degree is not higher than the set superheat degree value, control the first electromagnetic valve to be cut off and the fourth electromagnetic valve to be turned on.

[0021] The fluorine pump compressor double-cycle refrigeration system and the control method thereof have the following beneficial effects:

[0022] Before the refrigeration system is switched to the fluorine pump mode, the liquid refrigerant in the first liquid storage tank in the drainage state is at least partially released and discharged to the refrigerant cycle, so that the filling amount of the refrigerant in the refrigeration cycle is increased, thereby meeting the objective demand of the fluorine pump mode requiring more refrigerant, effectively reducing the pressure loss of the system in the fluorine pump mode, and improving the energy efficiency of the refrigeration system in the fluorine pump mode; before the refrigeration system is switched to the compressor mode, the refrigerant in the refrigerant cycle is partially stored in the first liquid storage tank, so that the refrigerant participating in the cycle during the operation of the refrigeration system in the compressor mode is relatively small, thereby improving the energy efficiency of the refrigeration system in the compressor mode; that is, in the technical solution, the first liquid storage tank is used to recycle and store and release the refrigerant in the system according to different operation modes of the refrigeration system, the refrigerant is designed redundantly, the problem of different optimal filling amounts of refrigerant required in the two modes is solved, the double-cycle system can be operated efficiently in the two operation modes, and the energy-saving effect is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. The drawings in the following description are only exemplary, and other drawings can be obtained by the provided drawings without creative labor for those skilled in the art.

[0024] Figure 1 is a principle schematic diagram of the fluorine pump compressor double-cycle refrigeration system of the embodiment of the present application;

[0025] Figure 2 is Figure 1 is a state schematic diagram of the fluorine pump compressor double-cycle refrigeration system in the embodiment when the system is operated in the compressor mode, the dashed line in the figure is the pipeline on state, the solid line is the cut-off state, and the third pipeline in the figure can be intermittently controlled under the corresponding condition;

[0026] Figure 3 is Figure 1 is a state schematic diagram of the fluorine pump compressor double-cycle refrigeration system in the embodiment when the system is operated in the fluorine pump mode;

[0027] Figure 4 is Figure 1 is a state diagram of the fluorine pump compressor double cycle refrigeration system in the liquid discharge mode;

[0028] Figure 5 is Figure 1 is a state diagram of the fluorine pump compressor double cycle refrigeration system in the liquid storage mode.

[0029] Reference signs are:

[0030] 1, compressor; 2, fluorine pump; 3, first liquid storage tank; 41, condenser; 411, outer fan; 42, second liquid storage tank; 43, evaporator; 431, inner fan; 44, throttling element; 5, oil separator; 51, capillary tube; 100, first pipeline; 101, first one-way valve; 200, second pipeline; 201, second one-way valve; 300, third pipeline; 301, first electromagnetic valve; 400, fourth pipeline; 401, second electromagnetic valve; 500, fifth pipeline; 501, third electromagnetic valve; 600, sixth pipeline; 601, fourth electromagnetic valve. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0032] In the description of the present application, it should be understood that the orientation words such as "front, back, up, down, left, right", "transverse, vertical, perpendicular, horizontal" and "top, bottom" and the like indicate the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate and imply that the indicated device or element must have a particular orientation or be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the scope of protection of the present application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.

[0033] For purposes of the description hereinafter, spatial relative terms, such as "above", "below", "upper", "lower", and the like, can be used to describe the relative position of one element or feature to another element or feature as illustrated in the figures. It will be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "up" other elements or features would then be oriented "below" or "down" the other elements or features. Thus, the exemplary term "above" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90° or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0034] In addition, it should be noted that the use of "first", "second", and the like, terminology throughout the specification is used to distinguish one element from another and does not necessarily indicate the order of elements or the order in which the elements are described. Unless otherwise indicated, the use of the singular is not intended to limit the number of elements to one.

[0035] With reference to the drawings Figures 1 to 5 As shown, according to an embodiment of the present application, a fluorine pump compressor double cycle refrigeration system is provided, in one specific embodiment applied to refrigeration and temperature adjustment of the environment in a machine room, the fluorine pump compressor double cycle refrigeration system comprising a compressor mode driven by a compressor 1 cycle and a fluorine pump mode driven by a fluorine pump 2 cycle, further comprising a first liquid storage tank 3, the first liquid storage tank 3 having a liquid storage state and a liquid discharge state, before the refrigeration system is switched from the compressor mode (as shown) to the fluorine pump mode (as shown), the first liquid storage tank 3 is in the liquid discharge state to at least partially release and discharge the liquid refrigerant in the first liquid storage tank 3 to the refrigerant cycle, before the refrigeration system is switched from the fluorine pump mode to the compressor mode, the first liquid storage tank 3 is in the liquid storage state to partially recover the liquid refrigerant in the refrigerant cycle and store it in the first liquid storage tank 3. Figure 1 Figure 2

[0036] ​​The technical scheme in the present application can increase the filling amount of refrigerant in the refrigeration cycle before the refrigeration system is switched to the fluorine pump mode, thereby meeting the objective requirement of the fluorine pump mode for more refrigerant, effectively reducing the pressure loss of the system in the fluorine pump mode, and improving the energy efficiency of the refrigeration system in the fluorine pump mode; and the refrigerant in the refrigeration cycle is stored in the first liquid storage tank 3 before the refrigeration system is switched to the compressor mode, so that the refrigeration system can run in the compressor mode with relatively less refrigerant participating in the circulation, thereby improving the energy efficiency of the refrigeration system in the compressor mode; that is, the technical scheme in the present application realizes the recovery, storage and release of refrigerant in the system through the first liquid storage tank 3 for different operation modes of the refrigeration system, realizes the redundancy design of refrigerant, solves the problem of different optimal filling amounts of refrigerant required in the two modes, and realizes high-efficiency operation of the double-circulation system in the two operation modes, thereby achieving energy-saving effect.

[0037] In some embodiments, referring to Figure 1 As shown in the figure, the fluorine pump-compressor double-circulation refrigeration system further comprises a condenser 41, a second liquid storage tank 42, an evaporator 43 and a throttling element 44 (such as a commonly used electronic expansion valve or throttling valve). The inlet of the condenser 41 is in communication with the exhaust port of the compressor 1, the outlet of the condenser 41 is in controllable communication with the pump inlet of the fluorine pump 2 via the second liquid storage tank 42, the pump outlet of the fluorine pump 2 is in communication with the inlet of the evaporator 43, the outlet of the evaporator 43 is in communication with the suction port of the compressor 1 and is in communication with the exhaust port of the compressor 1 via a first pipeline 100, the first pipeline 100 is provided with a first one-way valve 101, the one-way valve 101 is in one-way communication from the evaporator 43 to the condenser 41, the first liquid storage tank 3 and the outlet of the second liquid storage tank 42 are in communication via a second pipeline 200, and the second pipeline 200 is connected in series with the throttling element 44. When the first liquid storage tank 3 is in the liquid storage state, the liquid refrigerant in the second liquid storage tank 42 is driven by the fluorine pump 2 to enter the first liquid storage tank 3 via a third pipeline 300.

[0038] In the technical scheme, the liquid refrigerant pumped out of the fluorine pump 2 is introduced into the first liquid storage tank 3 for storage via the third pipeline 300, so as to meet the automatic liquid storage requirement of the first liquid storage tank 3, thereby realizing the reduction of the filling amount of refrigerant in the refrigeration cycle.

[0039] In some embodiments, when the first liquid storage tank 3 is in the liquid discharge state, the liquid refrigerant in the first liquid storage tank 3 enters the refrigeration cycle under the driving of the exhaust pressure of the compressor 1 via the third pipeline 300.

[0040] In the technical solution, the exhaust pressure of the compressor 1 is used to press the liquid refrigerant stored in the first liquid storage tank 3 into the refrigerant cycle, so as to increase the filling amount of the refrigerant in the refrigerant cycle.

[0041] In a preferred embodiment, a first electromagnetic valve 301 is connected in series on the third pipeline 300, and the recovery storage and release of the liquid refrigerant in the first liquid storage tank 3 are realized by controlling the on-off of the first electromagnetic valve 301; a fourth pipeline 400 is connected between the liquid outlet of the second liquid storage tank 42 and the pump inlet of the fluorine pump 2, a second electromagnetic valve 401 is connected in series on the fourth pipeline 400, the second pipeline 200 is communicated with the inlet side of the second electromagnetic valve 401, and the second electromagnetic valve 401 is controlled to be cut off when the refrigeration system is in the compressor mode, so as to ensure that the refrigerant enters the evaporator 43 after flowing through the first liquid storage tank 3, and the second electromagnetic valve 401 is controlled to be turned on when the refrigeration system is in the fluorine pump mode, so as to ensure that the refrigerant enters the evaporator 43 through the fluorine pump 2.

[0042] In some embodiments, the first liquid storage tank 3 is also communicated with the inlet of the condenser 41 through a fifth pipeline 500, a third electromagnetic valve 501 is connected in series on the fifth pipeline 500, and a sixth pipeline 600 is further included, a first end of the sixth pipeline 600 is communicated on the fifth pipeline 500 between the third electromagnetic valve 501 and the first liquid storage tank 3, a second end of the sixth pipeline 600 is communicated on the pipeline between the first electromagnetic valve 301 and the inlet of the evaporator 43, and a fourth electromagnetic valve 601 is connected in series on the sixth pipeline 600.

[0043] In the technical solution, by the on-off connection design of the fifth pipeline 500 and the sixth pipeline 600, the high-pressure refrigerant discharged by the compressor 1 can be introduced into the first liquid storage tank 3, and then the liquid refrigerant in the first liquid storage tank 3 can be pressed and released into the refrigerant cycle by the high-pressure exhaust of the compressor 1.

[0044] In some embodiments, a second one-way valve 201 is further connected in series on the second pipeline 200, and the on direction of the second one-way valve 201 is from the second liquid storage tank 42 to the first liquid storage tank 3, so as to ensure that the liquid refrigerant in the first liquid storage tank 3 can smoothly enter the refrigerant cycle through the third pipeline 300, and the high-pressure gas refrigerant cannot flow out through the second pipeline 200 to reduce the driving force of the liquid refrigerant.

[0045] To ensure sufficient lubrication of the moving frictional parts in the compressor 1 and cooling of the heat generating parts, in a preferred embodiment, an oil separator 5 is arranged between the discharge port of the compressor 1 and the inlet of the condenser 41 to enable a certain degree of separation of the lubricating oil in the discharged refrigerant, and the bottom of the oil separator 5 is communicated with the suction port of the compressor 1 through a capillary tube 51.

[0046] According to the embodiment of the present application, a control method of the dual-cycle refrigeration system of the fluorine pump compressor as described above is also provided, comprising the following steps:

[0047] obtaining a switching instruction of the operation mode of the refrigeration system;

[0048] After obtaining the switching instruction, before switching the dual-cycle refrigeration system of the fluorine pump compressor from the current operation mode to the target operation mode according to the switching instruction, an intermediate switching mode is run to store part of the liquid refrigerant in the refrigerant cycle in the first liquid storage tank 3 or release at least part of the liquid refrigerant in the first liquid storage tank 3 to the refrigerant cycle; specifically, when the current operation mode is the compressor mode and the target operation mode is the fluorine pump mode, the intermediate switching mode is the refrigerant discharge mode, to release at least part of the liquid refrigerant in the first liquid storage tank 3 to the refrigerant cycle, and then control the refrigeration system to run in the fluorine pump mode; or when the current operation mode is the fluorine pump mode and the target operation mode is the compressor mode, the intermediate switching mode is the refrigerant storage mode, to store part of the liquid refrigerant in the refrigerant cycle in the first liquid storage tank 3, and then control the refrigeration system to run in the compressor mode.

[0049] In the technical solution, before the refrigeration system is switched to the fluorine pump mode, at least part of the liquid refrigerant in the first liquid storage tank 3 in the discharge state is released to the refrigerant cycle, which increases the filling amount of the refrigerant in the refrigeration cycle, thereby meeting the objective demand of the fluorine pump mode for more refrigerant, effectively reducing the pressure loss of the system in the fluorine pump mode, and improving the energy efficiency of the refrigeration system in the fluorine pump mode; before the refrigeration system is switched to the compressor mode, part of the refrigerant in the refrigerant cycle is stored in the first liquid storage tank 3, which ensures that the refrigerant participating in the cycle is relatively small during the operation of the refrigeration system in the compressor mode, thereby improving the energy efficiency of the refrigeration system in the compressor mode; that is, in the technical solution, the first liquid storage tank 3 is used to store and release the refrigerant in the system according to different operation modes of the refrigeration system, to realize the redundancy design of the refrigerant, solve the problem of different optimal filling amounts of the refrigerant required in the two modes, and realize efficient operation of the dual-cycle system in the two operation modes, to achieve energy saving effect.

[0050] When the refrigeration system operates the compressor mode, referring to Figure 2 As shown in the figure, the compressor 1 is controlled to operate, the first electromagnetic valve 301 and the fourth electromagnetic valve 601 are controlled to be turned on, and the second electromagnetic valve 401 and the third electromagnetic valve 501 are controlled to be turned off. In this state, the opening degree of the throttling element 44 is reasonably adjusted according to a conventional control method. Of course, at this time, the fluorine pump 2 is in a state of shutdown and non-operation. In the compressor mode, the high-pressure and high-temperature refrigerant discharged from the compressor 1 passes through the oil separator 5, the condenser 41, the second liquid tank 42, the throttling element 44, the first liquid tank 3, the sixth pipeline 600, and the evaporator 43 in turn and then returns to the compressor 1 again.

[0051] When the refrigeration system operates the fluorine pump mode, referring to Figure 3 As shown in the figure, the fluorine pump 2 is controlled to operate, the second electromagnetic valve 401 is controlled to be turned on, and the first electromagnetic valve 301, the third electromagnetic valve 501, and the fourth electromagnetic valve 601 are controlled to be turned off. In this state, the compressor 1 is in a state of shutdown and non-operation, and the state of the throttling element 44 can remain unchanged (both open and closed). In the fluorine pump mode, the refrigerant driven by the fluorine pump 2 passes through the evaporator 43, the first pipeline 100, the oil separator 5, the condenser 41, and the second liquid tank 42 in turn and then returns to the fluorine pump 2.

[0052] In some embodiments, during the operation of the refrigeration system in the compressor mode, the following steps are further included:

[0053] The outlet superheat degree of the evaporator 43 is obtained. When the obtained outlet superheat degree is higher than a set superheat degree value, it indicates that the refrigeration system is in a liquid deficiency state. In this case, the first electromagnetic valve 301 is controlled to be turned on, and the fourth electromagnetic valve 601 is controlled to be turned off. In this case, the gas-liquid two-phase refrigerant enters the first liquid tank 3 through the second one-way valve 201 and then flows out through the third pipeline 300 at the bottom of the first liquid tank 3. The fourth electromagnetic valve 601 in the turned-off state can make the liquid discharge more smooth at this time. When the outlet superheat degree is not higher than the set superheat degree value, the first electromagnetic valve 301 is controlled to be turned off, and the fourth electromagnetic valve 601 is controlled to be turned on. In this case, the gas-liquid two-phase refrigerant enters the first liquid tank 3 through the second one-way valve 201 and then flows out through the upper outlet of the first liquid tank 3. The first liquid tank 3 can always maintain a full liquid level or a high liquid level. The redundant refrigerant of the refrigeration system is stored in the first liquid tank 3. In this way, automatic adjustment of the system in different states in the compressor mode is realized.

[0054] In some embodiments, referring to Figure 4As shown, when the refrigeration system operates in the refrigerant drainage mode, the compressor 1 is controlled to keep running, the third solenoid valve 501 and the first solenoid valve 301 are controlled to be turned on, and the fourth solenoid valve 601 and the second solenoid valve 401 are controlled to be cut off. At this time, the throttling element 44 can be controlled to be in the cut-off state, the high-pressure refrigerant discharged by the compressor 1 is introduced into the first liquid storage tank 3 through the fifth pipeline 500, at this time, the second check valve 201 is reversely cut off, the fourth solenoid valve 601 is controlled to be cut off, and the liquid refrigerant stored in the first liquid storage tank 3 is released into the refrigerant cycle through the third pipeline 300, thereby ensuring the filling amount of the refrigerant participating in the cycle in the fluorine pump mode. It can be understood that the first solenoid valve 301 is controlled to be cut off after the liquid refrigerant in the first liquid storage tank 3 is completely discharged. It should be noted that the running time of the drainage mode can be a fixed time, that is, the running time of the drainage mode can be set according to actual needs. In another feasible embodiment, a corresponding liquid level sensor can be arranged in the first liquid storage tank 3 to detect whether the drainage is completed.

[0055] When the refrigeration system operates in the refrigerant storage mode, the fluorine pump 2 is controlled to keep running, the first solenoid valve 301, the second solenoid valve 401, and the third solenoid valve 501 are controlled to be turned on, and the fourth solenoid valve 601 is controlled to be cut off. At this time, the throttling element 44 can be controlled to be in the cut-off state, the liquid refrigerant pumped by the fluorine pump 2 flows into the evaporator 43 to adjust the temperature of the machine room environment, and flows into the first liquid storage tank 3 to store the liquid refrigerant in the first liquid storage tank 3, thereby reducing the filling amount of the refrigerant in the refrigerant cycle and ensuring the operation efficiency of the refrigeration system in the compressor mode.

[0056] In a specific embodiment, when the refrigeration system is in the refrigerant storage mode, the corresponding inner fan 431 of the evaporator 43 is controlled to stop running, and the running time of the refrigerant storage mode is ensured to be t0, t0=V(f1+f2) / qf1, where V is the volume of the first liquid storage tank 3 (unit: m 3 ), q is the volume flow rate of the fluorine pump 2 (unit: m 3 / s), f1 is the pipe resistance of the refrigerant flowing from the fluorine pump 2 to the evaporator 43 (unit: kpa), and f2 is the pipe resistance of the refrigerant flowing from the fluorine pump 2 to the first liquid storage tank 3 (unit: kpa). In this technical solution, when the liquid is stored, the inner fan 431 is controlled to stop running to ensure that the pipe resistance flowing through the evaporator 43 is relatively fixed, thereby accurately estimating the time from the empty tank (in the fluorine pump mode) to the full liquid (in the compressor mode) of the first liquid storage tank 3, and further determining the running time of the refrigerant storage mode.

[0057] Those skilled in the art can easily understand that the advantageous technical features of the above-mentioned modes can be freely combined and superimposed without conflict.

[0058] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A dual cycle refrigeration system for a fluorine pump compressor, characterized by, The refrigeration system comprises a compressor mode driven by a compressor (1) and a fluorine pump mode driven by a fluorine pump (2), and further comprises a first liquid storage tank (3) having a liquid storage state and a liquid discharge state, wherein before the refrigeration system is switched from the compressor mode to the fluorine pump mode, the first liquid storage tank (3) is in the liquid discharge state to at least partially release the liquid refrigerant in the first liquid storage tank (3) to the refrigerant cycle, and before the refrigeration system is switched from the fluorine pump mode to the compressor mode, the first liquid storage tank (3) is in the liquid storage state to partially recover the liquid refrigerant in the refrigerant cycle into the first liquid storage tank (3).

2. The dual cycle refrigerant system of claim 1 wherein, The refrigeration system further comprises a condenser (41), a second liquid storage tank (42), an evaporator (43), and a throttling element (44), wherein the inlet of the condenser (41) is communicated with the exhaust port of the compressor (1), the outlet of the condenser (41) is controllably communicated with the pump inlet of the fluorine pump (2) via the second liquid storage tank (42), the pump outlet of the fluorine pump (2) is communicated with the inlet of the evaporator (43), the outlet of the evaporator (43) is communicated with the suction port of the compressor (1) and the exhaust port of the compressor (1) via a first pipeline (100), the first pipeline (100) is provided with a first one-way valve (101), the one-way valve (101) is in a one-way communication direction from the evaporator (43) to the condenser (41), the first liquid storage tank (3) is communicated with the liquid outlet of the second liquid storage tank (42) via a second pipeline (200), and the second pipeline (200) is connected with the throttling element (44) in series, when the first liquid storage tank (3) is in the liquid storage state, the liquid refrigerant in the second liquid storage tank (42) is driven by the fluorine pump (2) to partially enter the first liquid storage tank (3) via a third pipeline (300).

3. The dual cycle refrigerant system of claim 2 wherein, When the first liquid storage tank (3) is in the liquid discharge state, the liquid refrigerant in the first liquid storage tank (3) is driven by the exhaust pressure of the compressor (1) to enter the refrigerant cycle via the third pipeline (300).

4. The dual cycle refrigerant system of claim 3 wherein, The third pipeline (300) is connected with a first electromagnetic valve (301) in series; the pipeline between the liquid outlet of the second liquid storage tank (42) and the pump inlet of the fluorine pump (2) is a fourth pipeline (400), the fourth pipeline (400) is connected with a second electromagnetic valve (401) in series, and the second pipeline (200) is communicated with the fourth pipeline (400) at the inlet side of the second electromagnetic valve (401).

5. The dual cycle refrigerant system of claim 4 wherein, The first liquid storage tank (3) is also communicated with the inlet of the condenser (41) through a fifth pipeline (500), the third electromagnetic valve (501) is connected in the fifth pipeline (500) between the first liquid storage tank (3) and the third electromagnetic valve (501), and the sixth pipeline (600) is also arranged, the first end of the sixth pipeline (600) is communicated with the fifth pipeline (500) between the third electromagnetic valve (501) and the first liquid storage tank (3), the second end of the sixth pipeline (600) is communicated with the pipeline between the first electromagnetic valve (301) and the inlet of the evaporator (43), and the fourth electromagnetic valve (601) is connected in the sixth pipeline (600).

6. The dual cycle refrigerant system of claim 2 wherein, The second pipeline (200) is also connected with the second check valve (201), and the conduction direction of the second check valve (201) is from the second liquid storage tank (42) to the first liquid storage tank (3).

7. A control method for a dual cycle refrigeration system of a fluorine pump compressor as set forth in claim 5, characterized by, The method comprises the following steps: An operation mode switching instruction of the refrigeration system is acquired. After the switching instruction is acquired, before the fluorine pump compressor double-circulation refrigeration system is switched from the current operation mode to the target operation mode according to the switching instruction, an intermediate switching mode is run to recycle part of the liquid refrigerant in the refrigerant circulation to the first liquid storage tank (3) or at least partially release the liquid refrigerant in the first liquid storage tank (3) to the refrigerant circulation.

8. The control method according to claim 7, characterized by When the current operation mode is the compressor mode and the target operation mode is the fluorine pump mode, the intermediate switching mode is a refrigerant liquid discharge mode, and after the liquid refrigerant in the first liquid storage tank (3) is at least partially released to the refrigerant circulation, the refrigeration system is controlled to run in the fluorine pump mode. Or, when the current operation mode is the fluorine pump mode and the target operation mode is the compressor mode, the intermediate switching mode is a refrigerant liquid storage mode, and after part of the liquid refrigerant in the refrigerant circulation is recycled to the first liquid storage tank (3), the refrigeration system is controlled to run in the compressor mode.

9. The control method according to claim 8, characterized by, When the refrigeration system runs in the compressor mode, the compressor (1) is controlled to run, the first electromagnetic valve (301) and the fourth electromagnetic valve (601) are controlled to be turned on, and the second electromagnetic valve (401) and the third electromagnetic valve (501) are controlled to be cut off. When the refrigeration system runs in the fluorine pump mode, the fluorine pump (2) is controlled to run, the second electromagnetic valve (401) is controlled to be turned on, and the first electromagnetic valve (301), the third electromagnetic valve (501) and the fourth electromagnetic valve (601) are controlled to be cut off.

10. The control method according to claim 9, characterized by When the refrigeration system runs in the refrigerant liquid discharge mode, the compressor (1) is controlled to keep running, the third electromagnetic valve (501) and the first electromagnetic valve (301) are controlled to be turned on, and the fourth electromagnetic valve (601) and the second electromagnetic valve (401) are controlled to be cut off. When the refrigeration system runs in the refrigerant liquid storage mode, the fluorine pump (2) is controlled to keep running, the first electromagnetic valve (301), the second electromagnetic valve (401) and the third electromagnetic valve (501) are controlled to be turned on, and the fourth electromagnetic valve (601) is controlled to be cut off.

11. The control method according to claim 10, characterized by, When the refrigeration system is in the refrigerant storage mode, the evaporator (43) is controlled to stop running corresponding to the configuration of the inner fan (431), and the refrigerant storage mode is ensured to run for a time t0, t0=V(f1+f2) / qf1, wherein V is the volume of the first storage tank (3), q is the volume flow rate of the fluorine pump (2), f1 is the pipe resistance of the refrigerant flowing from the fluorine pump (2) to the evaporator (43), and f2 is the pipe resistance of the refrigerant flowing from the fluorine pump (2) to the first storage tank (3).

12. The control method according to claim 9, characterized by, During the operation of the compressor mode of the refrigeration system, the following steps are further included: The outlet superheat of the evaporator (43) is obtained, and when the obtained outlet superheat is higher than the set superheat value, the first electromagnetic valve (301) is controlled to be turned on and the fourth electromagnetic valve (601) is controlled to be cut off; when the outlet superheat is not higher than the set superheat value, the first electromagnetic valve (301) is controlled to be cut off and the fourth electromagnetic valve (601) is controlled to be turned on.

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