Water chilling unit capable of achieving multi-stage cold storage and multi-stage cold storage method thereof

Abstract

The invention discloses a water chilling unit capable of achieving multi-stage cold accumulation and a multi-stage cold accumulation method thereof, and the cold accumulation method comprises the steps that when the working mode of the water chilling unit is a cold accumulation mode, a first refrigeration unit, a second refrigeration unit and a cold accumulation pipeline part are controlled to start working; real-time third temperature information fed back by the third temperature sensor and a preset cold storage temperature range are obtained; when the third temperature information is within the preset cold storage temperature range, the first compressor and the second compressor are controlled to keep the working state unchanged; when the third temperature information is lower than the preset cold storage temperature range, the first compressor and the second compressor are controlled to be unloaded, and otherwise, the first compressor and the second compressor are controlled to be loaded; according to the method, when the water chilling unit executes the cold storage mode, a large amount of refrigerating capacity can be circularly stored in the cold storage box, and when the water chilling unit needs the large amount of refrigerating capacity within a short time or intermittently needs the large amount of refrigerating capacity, the large amount of refrigerating capacity is released through the cold storage box so as to meet the use requirements of the water chilling unit in special occasions.

Description

Technical Field

[0001] The present invention relates to the field of cold storage technology, and in particular to a chiller capable of multi-stage cold storage and a multi-stage cold storage method thereof. Background Art

[0002] The general chillers that are widely available on the market can effectively realize the refrigeration function and provide continuous and uniform cold water supply for environments that require comfort or process requirements; this type of traditional chiller is generally suitable for occasions where the demand for cooling capacity is continuous and uniform; however, when faced with uneven cooling capacity demand, such as a large amount of cooling capacity is required in a short period of time, or in some occasions where a large amount of cooling capacity is required intermittently, this type of traditional chiller is unable to cope with the situation; since traditional chillers cannot quickly provide the required large amount of cooling capacity in a short period of time, they cannot meet those occasions where there is a demand for a large amount of cooling capacity in a short period of time or a large amount of cooling capacity intermittently.

[0003] This limitation means that traditional chillers are often unable to provide sufficient cooling effect for process equipment with rapid and large heat dissipation, which greatly reduces the reliability of equipment operation. In order to solve this problem, the market urgently needs a new type of chiller that can flexibly respond to various cooling needs, especially those sudden and intermittent high-load cooling needs, to ensure the stable operation of process equipment and maximize production efficiency.

[0004] It can be seen that the existing technology still needs to be improved and enhanced. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a multi-stage cold storage method, which can provide a large amount of cooling capacity to the terminal when the chiller requires a large amount of cooling capacity in a short period of time or intermittently.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A multi-stage cold storage method, a chiller capable of multi-stage cold storage comprises a cold storage box, a controller, a cold storage pipeline, a first refrigeration unit and a second refrigeration unit, one side of the cold storage box, the first refrigeration unit and the second refrigeration unit are sequentially connected end to end through the cold storage pipeline; the cold storage pipeline comprises a third temperature sensor electrically connected to the controller, and the third temperature sensor is arranged on a connecting pipeline between an output end of one side of the cold storage box and a second input end of the first refrigeration unit; the first refrigeration unit comprises a first compressor electrically connected to the controller, and the second refrigeration unit comprises a second compressor electrically connected to the controller; the cold storage method comprises the steps of:

[0008] When the working mode of the chiller is the cold storage mode, the first refrigeration unit, the second refrigeration unit and the cold storage pipeline are controlled to start working;

[0009] Acquire real-time third temperature information fed back by the third temperature sensor, and acquire a preset cold storage temperature range;

[0010] When the third temperature information is within the preset cold storage temperature range, controlling the first compressor and the second compressor to maintain the working state unchanged;

[0011] When the third temperature information is lower than a preset cold storage temperature range, controlling the first compressor and the second compressor to unload;

[0012] When the third temperature information is higher than a preset cold storage temperature range, the first compressor and the second compressor are controlled to load.

[0013] In the multi-stage cold storage method, the first refrigeration unit further includes a first evaporator, a first condenser and a first condensing fan electrically connected to the controller, the first evaporator, the first compressor and the first condenser are connected to form a first refrigeration cycle; the second refrigeration unit further includes a second evaporator, a second condenser and a second condensing fan electrically connected to the controller, the second evaporator, the second compressor and the second condenser are connected to form a second refrigeration cycle; the cold storage pipeline part further includes a water pump electrically connected to the controller, the second output end of the second evaporator is connected to the input end of the cold storage tank through the water pump, the output end of the cold storage tank is connected to the second input end of the first evaporator, and the second output end of the first evaporator is connected to the second input end of the second evaporator; when the working mode of the chiller is the cold storage mode, controlling the first refrigeration unit, the second refrigeration unit and the cold storage pipeline part to start working includes:

[0014] When the chiller is in cold storage mode, the water pump is controlled to start working first;

[0015] When the preset buffer time is reached, the first condensing fan and the second condensing fan are controlled to start working, and then the first compressor and the second compressor are controlled to start working.

[0016] In the multi-stage cold storage method, the first refrigeration unit further includes a first pressure sensor electrically connected to the controller, and the first pressure sensor is arranged on the connecting pipeline between the first compressor and the first condenser; the second refrigeration unit further includes a third pressure sensor electrically connected to the controller, and the third pressure sensor is arranged on the connecting pipeline between the second compressor and the second condenser; the control refrigeration unit and the cold storage pipeline part start working, and then further includes:

[0017] Acquire real-time first pressure information fed back by the first pressure sensor and real-time third pressure information fed back by the third pressure sensor, and acquire a preset fan operating pressure range;

[0018] When the first pressure information is within the preset fan working pressure range, the first condensing fan is controlled to keep the working state unchanged; when the first pressure information is lower than the preset fan working pressure range, the first condensing fan is controlled to unload; when the first pressure information is higher than the preset fan working pressure range, the first condensing fan is controlled to load;

[0019] When the third pressure information is within the preset fan working pressure range, the second condensing fan is controlled to maintain the working state unchanged; when the third pressure information is lower than the preset fan working pressure range, the second condensing fan is controlled to unload; when the third pressure information is higher than the preset fan working pressure range, the second condensing fan is controlled to load.

[0020] In the multi-stage cold storage method, the first refrigeration unit further includes a first bypass pipeline portion electrically connected to the controller, one end of the first bypass pipeline portion is connected to the connecting pipeline of the first compressor and the first condenser, and the other end of the first bypass pipeline portion is connected to the first output end of the first evaporator; the second refrigeration unit further includes a second bypass pipeline portion electrically connected to the controller, one end of the second bypass pipeline portion is connected to the connecting pipeline of the second compressor and the second condenser, and the other end of the second bypass pipeline portion is connected to the second output end of the second evaporator; the real-time first pressure information fed back by the first pressure sensor and the real-time third pressure information fed back by the third pressure sensor are obtained, and then the following is further included:

[0021] Obtain the preset bypass working pressure range;

[0022] When the first pressure information is within the preset bypass working pressure range, the first bypass pipeline section is controlled to maintain the working state unchanged; when the first pressure information is lower than the preset bypass working pressure range, the first bypass pipeline section is controlled to start working; when the first pressure information is higher than the preset bypass working pressure range, the first bypass pipeline section is controlled to stop working;

[0023] When the third pressure information is within the preset bypass working pressure range, the second bypass pipeline section is controlled to maintain the working state unchanged; when the third pressure information is lower than the preset bypass working pressure range, the second bypass pipeline section is controlled to start working; when the third pressure information is higher than the preset bypass working pressure range, the second bypass pipeline section is controlled to stop working.

[0024] In the multi-stage cold storage method, the cold storage pipeline section further includes a flow protector, a fourth temperature sensor and a fifth temperature sensor which are electrically connected to the controller respectively, the fourth temperature sensor is arranged on the connecting pipeline between the second output end of the first evaporator and the second input end of the second evaporator, the fifth temperature sensor is arranged on the connecting pipeline between the second output end of the second evaporator and the water pump, and the flow protector is arranged on the connecting pipeline between the output end of the cold storage tank and the second input end of the first evaporator; the control of the first refrigeration unit, the second refrigeration unit and the cold storage pipeline section to start working also includes:

[0025] When the flow protector is disconnected, the first compressor and the second compressor are controlled to stop, and a flow cut-off alarm instruction is output;

[0026] When the flow protector is turned on, real-time fourth temperature information fed back by the fourth temperature sensor and real-time fifth temperature information fed back by the fifth temperature sensor are obtained, and a preset protection action temperature and a preset protection reset temperature are obtained;

[0027] When the fourth temperature information is less than the preset protection action temperature, the first compressor is controlled to stop and a low temperature alarm instruction is output; when the fourth temperature information is greater than or equal to the preset protection reset temperature, the first compressor is controlled to maintain the original working state unchanged and an alarm reset instruction is output;

[0028] When the fifth temperature information is less than the preset protection action temperature, the second compressor is controlled to shut down and a low temperature alarm instruction is output; when the fifth temperature information is greater than or equal to the preset protection reset temperature, the second compressor is controlled to maintain the original working state unchanged and an alarm reset instruction is output.

[0029] The present invention also correspondingly provides a chiller capable of multi-stage cold storage, the chiller capable of multi-stage cold storage adopts any of the multi-stage cold storage methods as described above to realize working control, the chiller capable of multi-stage cold storage includes a cold storage box, a controller, a cold storage pipeline part, a first refrigeration unit and a second refrigeration unit; the other side of the cold storage box is used to transport the cold source to the end; one side of the cold storage box, the first refrigeration unit and the second refrigeration unit are connected end to end in sequence through the cold storage pipeline part; the cold storage pipeline part includes a third temperature sensor electrically connected to the controller, and the third temperature sensor is arranged on the connecting pipeline between the output end of one side of the cold storage box and the second input end of the first refrigeration unit; the first refrigeration unit includes a first compressor electrically connected to the controller, and the second refrigeration unit includes a second compressor electrically connected to the controller.

[0030] In the chiller capable of multi-stage cold storage, the cold storage pipeline section also includes a flow protector, a water pump, a fourth temperature sensor and a fifth temperature sensor which are electrically connected to the controller respectively; the second output end of the second refrigeration unit is connected to the input end on one side of the cold storage tank through the water pump, and the fifth temperature sensor is arranged on the connecting pipeline between the second output end of the second refrigeration unit and the water pump; the flow protector is arranged on the connecting pipeline between the output end on one side of the cold storage tank and the second input end of the first refrigeration unit; the fourth temperature sensor is arranged on the connecting pipeline between the second output end of the first refrigeration unit and the second input end of the second refrigeration unit.

[0031] In the chiller capable of multi-stage cold storage, the second refrigeration unit has the same structure as the first refrigeration unit; the first refrigeration unit also includes a first evaporator, a first condenser, a first filter, a first expansion valve, and a first condensing fan, a first pressure sensor, a first temperature sensor, a second pressure sensor, and a second temperature sensor electrically connected to the controller; the first evaporator, the first compressor, the first condenser, the first filter, and the first expansion valve are connected end to end in sequence to form a first refrigeration cycle; the first temperature sensor and the first pressure sensor are arranged on the connecting pipeline between the first compressor and the first condenser; the second temperature sensor and the second pressure sensor are arranged on the connecting pipeline between the first evaporator and the first compressor.

[0032] In the chiller capable of multi-stage cold storage, the first refrigeration unit also includes a first bypass pipeline portion electrically connected to the controller, one end of the first bypass pipeline portion is connected to the connecting pipeline between the first compressor and the first condenser, and the other end of the bypass pipeline portion is connected to the first output end of the first evaporator.

[0033] In the chiller capable of multi-stage cold storage, a diffuser and a flow equalizer are provided in the cold storage box, the second output end of the evaporator is connected to the diffuser through an input end on one side of the cold storage box, and the output end of the flow equalizer is connected to the second input end of the evaporator through an output end on one side of the cold storage box.

[0034] Beneficial effects:

[0035] The present invention provides a multi-stage cold storage method. When the chiller executes the cold storage mode, a large amount of cooling capacity is circulated and stored in a cold storage box through the first refrigeration unit and the second refrigeration unit. When the chiller requires a large amount of cooling capacity in a short period of time or intermittently requires a large amount of cooling capacity, a large amount of cooling capacity is released through the cold storage box to meet the use requirements of the chiller in special occasions; further, the working states of the first compressor and the second compressor are adjusted according to the real-time third temperature information fed back by the third temperature sensor to ensure that the cooling capacity in the cold storage box can meet the cold storage temperature requirement, thereby ensuring sufficient supply of cooling capacity and meeting the large cooling capacity usage requirement when the chiller executes the refrigeration mode; further, the first refrigeration unit cooperates with the second refrigeration unit to store cold for the cold storage box, and adopts multi-stage circulating water cooling technology, which can efficiently utilize low-grade cold sources, significantly improve the overall energy efficiency ratio of the chiller with multi-stage cold storage, not only optimize the energy utilization efficiency, but also greatly reduce energy consumption, and achieve the dual goals of energy saving and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A first logic flow chart of the multi-stage cold storage method provided by the present invention;

[0037] Figure 2 A second logic flow chart of the multi-stage cold storage method provided by the present invention;

[0038] Figure 3 A third logic flow chart of the multi-stage cold storage method provided by the present invention;

[0039] Figure 4 A fourth logic flow chart of the multi-stage cold storage method provided by the present invention;

[0040] Figure 5 A schematic structural diagram of a chiller capable of multi-stage cold storage provided by the present invention.

[0041] Main component symbol description: 1-cold storage box, 11-diffuser, 12-flow equalizer, 21-water pump, 22-flow protector, 23-third temperature sensor, 24-fourth temperature sensor, 25-fifth temperature sensor, 301-first compressor, 302-first condenser, 303-first filter, 304-first expansion valve, 305-first evaporator, 306-first condensing fan, 307-first temperature sensor, 308-first pressure sensor, 309-second temperature sensor, 310-second pressure sensor , 311-first bypass regulating valve, 312-first bypass on-off valve, 313-first throttling device, 401-second compressor, 402-second condenser, 403-second filter, 404-second expansion valve, 405-second evaporator, 406-second condensing fan, 407-sixth temperature sensor, 408-third pressure sensor, 409-seventh temperature sensor, 410-fourth pressure sensor, 411-second bypass regulating valve, 412-second bypass on-off valve, 413-second throttling device, 5-controller. DETAILED DESCRIPTION

[0042] The present invention provides a chiller capable of multi-stage cold storage and a multi-stage cold storage method thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples.

[0043] In the description of the present invention, it should be understood that the terms "installation", "connection" and the like should be understood in a broad sense, and a person skilled in the art can understand the specific meanings of the above terms in the present invention according to specific circumstances.

[0044] In this embodiment, the preset cold storage temperature range, the preset buffer time, the preset fan reset pressure, the preset bypass action pressure, the preset bypass reset pressure, the preset protection action temperature and the preset protection reset temperature are pre-set by the staff according to the design parameters and operating environment of the chiller, and can be modified and set through the display screen panel of the chiller.

[0045] See also Figure 1 and Figure 5The present invention provides a multi-stage cold storage method. The cold water unit capable of multi-stage cold storage includes a cold storage tank 1, a controller 5, a cold storage pipeline, a first refrigeration unit and a second refrigeration unit. One side of the cold storage tank 1, the first refrigeration unit and the second refrigeration unit are sequentially connected end to end through the cold storage pipeline; the cold storage pipeline includes a third temperature sensor 23 electrically connected to the controller 5, and the third temperature sensor 23 is arranged on a connecting pipeline between an output end of one side of the cold storage tank 1 and a second input end of the first refrigeration unit; the first refrigeration unit includes a first compressor 301 electrically connected to the controller 5, and the second refrigeration unit includes a second compressor 401 electrically connected to the controller 5; the cold storage method includes the steps of:

[0046] 101. When the working mode of the chiller is the cold storage mode, the first refrigeration unit, the second refrigeration unit and the cold storage pipeline are controlled to start working;

[0047] 102. Obtaining real-time third temperature information fed back by the third temperature sensor 23, and obtaining a preset cold storage temperature range;

[0048] 103. When the third temperature information is within the preset cold storage temperature range, the first compressor 301 and the second compressor 401 are controlled to maintain the working state unchanged;

[0049] In this embodiment, the preset cold storage temperature range is [preset cold storage temperature-preset cold storage accuracy, preset cold storage temperature+preset cold storage accuracy].

[0050] 104. When the third temperature information is lower than the preset cold storage temperature range, the first compressor 301 and the second compressor 401 are controlled to unload;

[0051] 105. When the third temperature information is higher than the preset cold storage temperature range, control the first compressor 301 and the second compressor 401 to load;

[0052] In this embodiment, when the third temperature information is greater than the preset cold storage temperature + the preset cold storage accuracy, the first compressor 301 and the second compressor 401 are controlled to load to increase the cooling intensity and quickly adjust the temperature back to the cold storage temperature range; on the contrary, when the third temperature information is less than the preset cold storage temperature - the preset cold storage accuracy, the first compressor 301 and the second compressor 401 are controlled to unload to reduce the cooling output and avoid overcooling, thereby ensuring that the cold storage temperature in the cold storage box 1 remains within the preset cold storage temperature range; further, according to the comparison result, a PID regulator can be used to adjust the unloading process and loading process of the first compressor 301 and the second compressor 401.

[0053] The present application discloses a multi-stage cold storage method. When the chiller executes the cold storage mode, a large amount of cooling capacity is circulated and stored in the cold storage box 1 through the first refrigeration unit and the second refrigeration unit. When the chiller requires a large amount of cooling capacity in a short period of time or intermittently, a large amount of cooling capacity is released through the cold storage box 1 to meet the use requirements of the chiller in special occasions; further, the working states of the first compressor 301 and the second compressor 401 are adjusted according to the real-time third temperature information fed back by the third temperature sensor 23 to ensure that the cooling capacity in the cold storage box 1 can meet the cold storage temperature requirement, thereby ensuring sufficient supply of cooling capacity and meeting the large cooling capacity usage requirement when the chiller executes the refrigeration mode; further, the first refrigeration unit cooperates with the second refrigeration unit to store cold for the cold storage box 1, and adopts multi-stage circulating water cooling technology, which can efficiently utilize low-grade cold sources, significantly improve the overall energy efficiency ratio of the chiller with multi-stage cold storage, not only optimize the energy utilization efficiency, but also greatly reduce energy consumption, and achieve the dual goals of energy saving and environmental protection.

[0054] For further information, see Figure 2 and Figure 5 , the first refrigeration unit also includes a first evaporator 305, a first condenser 302 and a first condensing fan 306 electrically connected to the controller 5, the first evaporator 305, the first compressor 301 and the first condenser 302 are connected to form a first refrigeration cycle; the second refrigeration unit also includes a second evaporator 405, a second condenser 402 and a second condensing fan 406 electrically connected to the controller 5, the second evaporator 405, the second compressor 401 and the second condenser 402 are connected to form a second refrigeration cycle; the cold storage pipeline part also includes a water pump 21 electrically connected to the controller 5, the second output end of the second evaporator 405 is connected to the input end of the cold storage tank 1 through the water pump 21, the output end of the cold storage tank 1 is connected to the second input end of the first evaporator 305, and the second output end of the first evaporator 305 is connected to the second input end of the second evaporator 405; when the working mode of the chiller is the cold storage mode, the first refrigeration unit, the second refrigeration unit and the cold storage pipeline part are controlled to start working, including:

[0055] 201. When the working mode of the chiller is the cold storage mode, the water pump 21 is controlled to start working;

[0056] 202. When the preset buffer time is reached, the first condensing fan 306 and the second condensing fan 406 are controlled to start working, and then the first compressor 301 and the second compressor 401 are controlled to start working.

[0057] In this embodiment, the first condensing fan 306 and the second condensing fan 406 are controlled to start first, and the first compressor 301 and the second compressor 401 are controlled to start later. The timely start of the two condensing fans helps to quickly establish the condensing pressure, creating conditions for the efficient operation of the corresponding compressors. Specifically, if the compressor is turned on first, there will be a problem that the high-temperature and high-pressure exhaust gas of the compressor cannot be cooled down and reduced in time after it comes out, because the condensing fan generally takes some time to start, but the high pressure of the compressor rises very quickly. After the compressor is started, the condensing fan is turned on again. At this time, the condensing fan will not have time to cool the high-pressure exhaust gas of the compressor, which will cause the exhaust pressure of the compressor to rise sharply, and a high-pressure alarm problem will occur.

[0058] For further information, see Figure 3 and Figure 5 , the first refrigeration unit further includes a first pressure sensor 308 electrically connected to the controller 5, and the first pressure sensor 308 is arranged on the connecting pipeline between the first compressor 301 and the first condenser 302; the second refrigeration unit further includes a third pressure sensor 408 electrically connected to the controller 5, and the third pressure sensor 408 is arranged on the connecting pipeline between the second compressor 401 and the second condenser 402; the control refrigeration unit and the cold storage pipeline part start working, and then further includes:

[0059] 301. Obtaining real-time first pressure information fed back by the first pressure sensor 308 and real-time third pressure information fed back by the third pressure sensor 408, and obtaining a preset fan operating pressure range;

[0060] In this embodiment, the preset fan operating pressure range is [preset fan reset pressure-preset reset pressure accuracy, preset fan reset pressure+preset reset pressure accuracy].

[0061] 302. When the first pressure information is within the preset fan working pressure range, the first condensing fan 306 is controlled to keep the working state unchanged; when the first pressure information is lower than the preset fan working pressure range, the first condensing fan 306 is controlled to unload; when the first pressure information is higher than the preset fan working pressure range, the first condensing fan 306 is controlled to load;

[0062] In this embodiment, the pressure of the first refrigeration unit is monitored in real time by the first pressure sensor 308. When the pressure is higher than the preset fan operating pressure range, the controller 5 will automatically instruct the first condensing fan 306 to load and operate, thereby ensuring that the chiller with multi-stage cold storage operates in a high-efficiency state; conversely, when the pressure is lower than the preset fan operating pressure range, the controller 5 will control the first condensing fan 306 to unload, thereby reducing unnecessary energy consumption. This intelligent adjustment mechanism not only improves the operating efficiency of the chiller with multi-stage cold storage, but also extends the service life of the first condensing fan 306.

[0063] 303. When the third pressure information is within the preset fan working pressure range, the second condensing fan 406 is controlled to keep the working state unchanged; when the third pressure information is lower than the preset fan working pressure range, the second condensing fan 406 is controlled to unload; when the third pressure information is higher than the preset fan working pressure range, the second condensing fan 406 is controlled to load;

[0064] In this embodiment, the pressure of the second refrigeration unit is monitored in real time by the third pressure sensor 408. When the pressure exceeds the preset fan operating pressure range, the controller 5 will automatically instruct the second condensing fan 406 to load and operate, thereby ensuring that the chiller with multi-stage cold storage operates in a high-efficiency state; conversely, when the pressure is lower than the preset fan operating pressure range, the controller 5 will control the second condensing fan 406 to unload, thereby reducing unnecessary energy consumption. This intelligent adjustment mechanism not only improves the operating efficiency of the chiller with multi-stage cold storage, but also extends the service life of the second condensing fan 406.

[0065] For further information, see Figure 3 and Figure 5 , the first refrigeration unit further includes a first bypass pipeline portion electrically connected to the controller 5, one end of the first bypass pipeline portion is connected to the connecting pipeline of the first compressor 301 and the first condenser 302, and the other end of the first bypass pipeline portion is connected to the first output end of the first evaporator 305; the second refrigeration unit further includes a second bypass pipeline portion electrically connected to the controller 5, one end of the second bypass pipeline portion is connected to the connecting pipeline of the second compressor 401 and the second condenser 402, and the other end of the second bypass pipeline portion is connected to the second output end of the second evaporator 405; the real-time first pressure information fed back by the first pressure sensor 308 and the real-time third pressure information fed back by the third pressure sensor 408 are obtained, and then the following is further included:

[0066] 304. Obtaining a preset bypass working pressure range;

[0067] In this embodiment, the preset bypass working pressure range is [preset bypass reset pressure-preset bypass pressure accuracy, preset bypass action pressure+preset bypass pressure accuracy].

[0068] 305. When the first pressure information is within the preset bypass working pressure range, the first bypass pipeline section is controlled to maintain the working state unchanged; when the first pressure information is lower than the preset bypass working pressure range, the first bypass pipeline section is controlled to start working; when the first pressure information is higher than the preset bypass working pressure range, the first bypass pipeline section is controlled to stop working;

[0069] 306. When the third pressure information is within the preset bypass working pressure range, the second bypass pipeline section is controlled to maintain the working state unchanged; when the third pressure information is lower than the preset bypass working pressure range, the second bypass pipeline section is controlled to start working; when the third pressure information is higher than the preset bypass working pressure range, the second bypass pipeline section is controlled to stop working.

[0070] For operation under certain ambient temperatures, when there is no bypass pipeline section, the condensing fan is able to provide sufficient cooling for the compressor exhaust. However, when the outdoor ambient temperature rises significantly, the cooling effect of the condensing fan will be insufficient, resulting in a significant increase in the high pressure of the compressor, which is likely to cause a high pressure alarm. In this embodiment, by setting a first bypass pipeline section and a second bypass pipeline section, when the exhaust pressure of the first compressor 301 or the second compressor 401 rises significantly and is higher than the preset bypass working pressure range, the corresponding first bypass pipeline section or the second bypass pipeline section starts to work, and timely bypasses a part of the refrigerant of the high-pressure exhaust of the first compressor 301 and the second compressor 401 into the intake port of the first compressor 301 or the second compressor 401. In this way, even when the ambient temperature is very high and the first condensing fan 306 or the second condensing fan 406 is insufficiently cooled, the bypass pipeline section can be used to relieve the pressure, thereby ensuring that the first compressor 301 and the second compressor 401 can still operate stably and reliably under very high ambient temperatures.

[0071] For further information, see Figure 4 and Figure 5, the cold storage pipeline section also includes a flow protector 22, a fourth temperature sensor 24 and a fifth temperature sensor 25 which are electrically connected to the controller 5 respectively, the fourth temperature sensor 24 is arranged on the connecting pipeline between the second output end of the first evaporator 305 and the second input end of the second evaporator 405, the fifth temperature sensor 25 is arranged on the connecting pipeline between the second output end of the second evaporator 405 and the water pump 21, and the flow protector 22 is arranged on the connecting pipeline between the output end of the cold storage tank 1 and the second input end of the first evaporator 305; the control of the first refrigeration unit, the second refrigeration unit and the cold storage pipeline section to start working, and then further includes:

[0072] 401. When the flow protector 22 is disconnected, the first compressor 301 and the second compressor 401 are controlled to stop, and a flow cut-off alarm instruction is output;

[0073] In this embodiment, when the flow protector 22 detects an abnormal situation and disconnects, the controller 5 will respond quickly, automatically control the first compressor 301 and the second compressor 401 to shut down, and simultaneously output a flow interruption alarm signal, thereby avoiding equipment damage caused by abnormal flow. It also reminds the operator to take corresponding measures through timely alarms, greatly improving the safety performance of the chiller during operation.

[0074] 402. When the flow protector 22 is turned on, the real-time fourth temperature information fed back by the fourth temperature sensor 24 and the real-time fifth temperature information fed back by the fifth temperature sensor 25 are obtained, and a preset protection action temperature and a preset protection reset temperature are obtained;

[0075] 403. When the fourth temperature information is less than the preset protection action temperature, the first compressor 301 is controlled to stop, and a low temperature alarm instruction is output; when the fourth temperature information is greater than or equal to the preset protection reset temperature, the first compressor 301 is controlled to maintain the original working state unchanged, and an alarm reset instruction is output;

[0076] In this embodiment, the fourth temperature sensor 24 is arranged at the second output end of the first evaporator 305. The temperature of the cold source output by the second output port will be relatively low after being cooled. When the outlet water temperature is lower than the preset protection action temperature, the inside of the second evaporator 405 is very easy to freeze. After freezing, the volume will expand and burst the second evaporator 405, causing damage to the second evaporator 405; therefore, a protection mechanism should be set for the second evaporator 405 according to the fourth temperature information. When the fourth temperature information is less than the preset protection action temperature, it is necessary to control the first compressor 301 to shut down and stop refrigeration to prevent the cold water host from being frozen; when the flow protector 22 is turned on and the fourth temperature information is greater than or equal to the preset protection reset temperature, the controller 5 will automatically reset the alarm and maintain the original operating state of the first compressor 301, so that the cold water unit with multi-stage cold storage can quickly return to normal working state after the temperature returns to normal, avoiding unnecessary downtime and improving work efficiency and equipment operation efficiency.

[0077] 404. When the fifth temperature information is less than the preset protection action temperature, the second compressor 401 is controlled to stop, and a low temperature alarm instruction is output; when the fifth temperature information is greater than or equal to the preset protection reset temperature, the second compressor 401 is controlled to maintain the original working state unchanged, and an alarm reset instruction is output;

[0078] In this embodiment, the fifth temperature sensor 25 is arranged at the second output end of the second evaporator 405. The temperature of the cold source output by the second output port will be relatively low after being cooled. When the outlet water temperature is lower than the preset protection action temperature, the inside of the second evaporator 405 is very easy to freeze. After freezing, the volume will expand and burst the second evaporator 405, causing damage to the second evaporator 405; therefore, a protection mechanism should be set for the second evaporator 405 according to the fifth temperature information. When the fifth temperature information is less than the preset protection action temperature, it is necessary to control the second compressor 401 to shut down and stop refrigeration to prevent the cold water host from being frozen; when the flow protector 22 is turned on and the fifth temperature information is greater than or equal to the preset protection reset temperature, the controller 5 will automatically reset the alarm and maintain the original operating state of the second compressor 401, so that the cold water unit with multi-stage cold storage can quickly return to normal working state after the temperature returns to normal, avoiding unnecessary downtime and improving work efficiency and equipment operation efficiency.

[0079] See also Figure 5The present invention also provides a chiller capable of multi-stage cold storage, wherein the chiller capable of multi-stage cold storage adopts any of the multi-stage cold storage methods described above to realize working control, and the chiller capable of multi-stage cold storage comprises a cold storage tank 1, a controller 5, a cold storage pipeline, a first refrigeration unit and a second refrigeration unit; the other side of the cold storage tank 1 is used to transport a cold source to a terminal; one side of the cold storage tank 1, the first refrigeration unit and the second refrigeration unit are connected end to end in sequence through the cold storage pipeline; the cold storage pipeline comprises a third temperature sensor 23 electrically connected to the controller 5, and the third temperature sensor 23 is arranged on a connecting pipeline between an output end of one side of the cold storage tank 1 and a second input end of the first refrigeration unit; the first refrigeration unit comprises a first compressor 301 electrically connected to the controller 5, and the second refrigeration unit comprises a second compressor 401 electrically connected to the controller 5.

[0080] In this example, see Figure 5 A cold water supply pipe and a cold water return pipe are provided on the other side of the cold storage tank 1, and the cold water supply pipe and the cold water return pipe are respectively used to connect the ends to transport the cold source to the ends.

[0081] For further information, see Figure 5 The cold storage pipeline portion also includes a flow protector 22, a water pump 21, a fourth temperature sensor 24 and a fifth temperature sensor 25 which are electrically connected to the controller 5 respectively; the second output end of the second refrigeration unit is connected to the input end of one side of the cold storage tank 1 through the water pump 21, and the fifth temperature sensor 25 is arranged on the connecting pipeline between the second output end of the second refrigeration unit and the water pump 21; the flow protector 22 is arranged on the connecting pipeline between the output end of one side of the cold storage tank 1 and the second input end of the first refrigeration unit; the fourth temperature sensor 24 is arranged on the connecting pipeline between the second output end of the first refrigeration unit and the second input end of the second refrigeration unit.

[0082] For further information, see Figure 5The first refrigeration unit also includes a first evaporator 305, a first condenser 302, a first filter 303, a first expansion valve 304, and a first condensing fan 306, a first pressure sensor 308, a first temperature sensor 307, a second pressure sensor 310 and a second temperature sensor 309 electrically connected to the controller 5; the first evaporator 305, the first compressor 301, the first condenser 302, the first filter 303 and the first expansion valve 304 are connected end to end in sequence to form a first refrigeration cycle; the first temperature sensor 307 and the first pressure sensor 308 are arranged on the connecting pipeline between the first compressor 301 and the first condenser 302; the second temperature sensor 309 and the second pressure sensor 310 are arranged on the connecting pipeline between the first evaporator 305 and the first compressor 301.

[0083] In this embodiment, the first temperature sensor 307 and the first pressure sensor 308 are arranged on the connecting pipeline between the first compressor 301 and the first condenser 302, and are used to monitor the state of the high-temperature and high-pressure refrigerant discharged from the first compressor 301 in real time, ensuring that it reaches the ideal temperature and pressure before entering the first condenser 302; while the second temperature sensor 309 and the second pressure sensor 310 are located on the connecting pipeline between the first evaporator 305 and the first compressor 301, and are responsible for monitoring the state of the low-temperature and low-pressure refrigerant returning from the first evaporator 305 to the first compressor 301, ensuring that the refrigerant reaches suitable conditions before re-entering the first compressor 301.

[0084] For further information, see Figure 5 The first refrigeration unit also includes a first bypass pipeline portion electrically connected to the controller 5, one end of the first bypass pipeline portion is connected to the connecting pipeline between the first compressor 301 and the first condenser 302, and the other end of the bypass pipeline portion is connected to the first output end of the first evaporator 305.

[0085] In this example, see Figure 5 The first bypass pipeline section includes a first bypass on-off valve 312, a first bypass regulating valve 311 and a first throttling device 313, one end of the first bypass on-off valve 312 is connected to the connecting pipeline between the first compressor 301 and the first condenser 302, and the other end of the first bypass on-off valve 312 is connected to the first output end of the first evaporator 305 through the first bypass regulating valve 311 and the first throttling device 313 connected in sequence; when the first bypass pipeline section starts to work, the first bypass on-off valve 312 is opened to conduct the first bypass pipeline, and the first bypass regulating valve 311 is opened according to a preset opening; when the first bypass pipeline section stops working, the first bypass on-off valve 312 and the first bypass regulating valve 311 are closed to close the first bypass pipeline.

[0086] For further information, see Figure 5 The second refrigeration unit also includes a second evaporator 405, a second condenser 402, a second filter 403, a second expansion valve 404, and a second condensing fan 406, a third pressure sensor 408, a sixth temperature sensor 407, a fourth pressure sensor 410 and a seventh temperature sensor 409 electrically connected to the controller 5; the second evaporator 405, the second compressor 401, the second condenser 402, the second filter 403 and the second expansion valve 404 are connected end to end in sequence to form a second refrigeration cycle; the sixth temperature sensor 407 and the third pressure sensor 408 are arranged on the connecting pipeline between the second compressor 401 and the second condenser 402; the seventh temperature sensor 409 and the fourth pressure sensor 410 are arranged on the connecting pipeline between the second evaporator 405 and the second compressor 401.

[0087] In this embodiment, the sixth temperature sensor 407 and the third pressure sensor 408 are arranged on the connecting pipeline between the second compressor 401 and the second condenser 402, and are used to monitor the state of the high-temperature and high-pressure refrigerant discharged from the second compressor 401 in real time to ensure that it reaches the ideal temperature and pressure before entering the second condenser 402; and the seventh temperature sensor 409 and the fourth pressure sensor 410 are located on the connecting pipeline between the second evaporator 405 and the second compressor 401, and are responsible for monitoring the state of the low-temperature and low-pressure refrigerant returning from the second evaporator 405 to the second compressor 401 to ensure that the refrigerant reaches suitable conditions before re-entering the second compressor 401.

[0088] For further information, see Figure 5 The second refrigeration unit also includes a second bypass pipeline portion electrically connected to the controller 5, one end of the second bypass pipeline portion is connected to the connecting pipeline between the second compressor 401 and the second condenser 402, and the other end of the bypass pipeline portion is connected to the second output end of the second evaporator 405.

[0089] In this example, see Figure 5The second bypass pipeline section includes a second bypass on-off valve 412, a second bypass regulating valve 411 and a second throttling device 413, one end of the second bypass on-off valve 412 is connected to the connecting pipeline of the second compressor 401 and the second condenser 402, and the other end of the second bypass on-off valve 412 is connected to the second output end of the second evaporator 405 through the second bypass regulating valve 411 and the second throttling device 413 connected in sequence; when the second bypass pipeline section starts to work, the second bypass on-off valve 412 is opened to conduct the second bypass pipeline, and the second bypass regulating valve 411 is opened according to a preset opening; when the second bypass pipeline section stops working, the second bypass on-off valve 412 and the second bypass regulating valve 411 are closed to close the second bypass pipeline.

[0090] In this example, see Figure 5 A diffuser 11 and a flow equalizer 12 are provided in the cold storage box 1. The second output end of the second evaporator 405 is connected to the diffuser 11 through an input end on one side of the cold storage box 1. The output end of the flow equalizer 12 is connected to the second input end of the first evaporator 305 through an output end on one side of the cold storage box 1.

[0091] In this embodiment, by arranging a diffuser 11 and a flow equalizer 12 in the cold storage box 1, the cooling efficiency and performance of the cold storage mechanism are significantly improved; firstly, the introduction of the diffuser 11 enables the coolant to be evenly distributed in the entire cold storage box 1, avoiding the problem of uneven cooling effect caused by the accumulation of coolant in certain areas. This uniform distribution characteristic ensures that every corner can be fully cooled, thereby improving the overall cold storage efficiency; secondly, the introduction of the diffuser 11 optimizes the flow path of the coolant, reduces the flow resistance, and further improves the flow efficiency of the coolant; in addition, the flow equalizer 12 connected to the second input end of the first evaporator 305 through the output end on one side of the cold storage box 1 ensures that the coolant can be evenly mixed and distributed before returning to the first evaporator 305. This uniform flow characteristic not only improves the utilization efficiency of the coolant, but also ensures that the first evaporator 305 can operate in an optimal state, thereby improving the cold storage effect of the cold storage mechanism.

[0092] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A multi-stage cold storage method, characterized in that: A chiller capable of multi-stage cold storage comprises a cold storage tank, a controller, a cold storage pipeline, a first refrigeration unit and a second refrigeration unit, one side of the cold storage tank, the first refrigeration unit and the second refrigeration unit are sequentially connected end to end through the cold storage pipeline; the cold storage pipeline comprises a third temperature sensor electrically connected to the controller, and the third temperature sensor is arranged on a connecting pipeline between an output end of one side of the cold storage tank and a second input end of the first refrigeration unit; the first refrigeration unit comprises a first compressor electrically connected to the controller, and the second refrigeration unit comprises a second compressor electrically connected to the controller; the cold storage method comprises the steps of: When the working mode of the chiller is the cold storage mode, the first refrigeration unit, the second refrigeration unit and the cold storage pipeline are controlled to start working; Acquire real-time third temperature information fed back by the third temperature sensor, and acquire a preset cold storage temperature range; When the third temperature information is within the preset cold storage temperature range, controlling the first compressor and the second compressor to maintain the working state unchanged; When the third temperature information is lower than a preset cold storage temperature range, controlling the first compressor and the second compressor to unload; When the third temperature information is higher than a preset cold storage temperature range, the first compressor and the second compressor are controlled to load.

2. A multi-stage cold storage method according to claim 1, characterized in that: The first refrigeration unit further includes a first evaporator, a first condenser and a first condensing fan electrically connected to the controller, the first evaporator, the first compressor and the first condenser are connected to form a first refrigeration cycle; the second refrigeration unit further includes a second evaporator, a second condenser and a second condensing fan electrically connected to the controller, the second evaporator, the second compressor and the second condenser are connected to form a second refrigeration cycle; the cold storage pipeline portion further includes a water pump electrically connected to the controller, the second output end of the second evaporator is connected to the input end of the cold storage tank through the water pump, the output end of the cold storage tank is connected to the second input end of the first evaporator, and the second output end of the first evaporator is connected to the second input end of the second evaporator; When the working mode of the chiller is the cold storage mode, controlling the first refrigeration unit, the second refrigeration unit and the cold storage pipeline part to start working includes: When the chiller is in cold storage mode, the water pump is controlled to start working first; When the preset buffer time is reached, the first condensing fan and the second condensing fan are controlled to start working, and then the first compressor and the second compressor are controlled to start working.

3. A multi-stage cold storage method according to claim 2, characterized in that: The first refrigeration unit further includes a first pressure sensor electrically connected to the controller, and the first pressure sensor is arranged on a connecting pipe between the first compressor and the first condenser; the second refrigeration unit further includes a third pressure sensor electrically connected to the controller, and the third pressure sensor is arranged on a connecting pipe between the second compressor and the second condenser; The control refrigeration unit and the cold storage pipeline part start working, and then further includes: Acquire real-time first pressure information fed back by the first pressure sensor and real-time third pressure information fed back by the third pressure sensor, and acquire a preset fan operating pressure range; When the first pressure information is within the preset fan working pressure range, the first condensing fan is controlled to keep the working state unchanged; when the first pressure information is lower than the preset fan working pressure range, the first condensing fan is controlled to unload; when the first pressure information is higher than the preset fan working pressure range, the first condensing fan is controlled to load; When the third pressure information is within the preset fan working pressure range, the second condensing fan is controlled to maintain the working state unchanged; when the third pressure information is lower than the preset fan working pressure range, the second condensing fan is controlled to unload; when the third pressure information is higher than the preset fan working pressure range, the second condensing fan is controlled to load.

4. A multi-stage cold storage method according to claim 3, characterized in that: The first refrigeration unit further includes a first bypass pipeline portion electrically connected to the controller, one end of the first bypass pipeline portion is connected to the connecting pipeline of the first compressor and the first condenser, and the other end of the first bypass pipeline portion is connected to the first output end of the first evaporator; the second refrigeration unit further includes a second bypass pipeline portion electrically connected to the controller, one end of the second bypass pipeline portion is connected to the connecting pipeline of the second compressor and the second condenser, and the other end of the second bypass pipeline portion is connected to the second output end of the second evaporator; the real-time first pressure information fed back by the first pressure sensor and the real-time third pressure information fed back by the third pressure sensor are obtained, and then the following is further included: Get the preset bypass working pressure range; When the first pressure information is within the preset bypass working pressure range, the first bypass pipeline section is controlled to maintain the working state unchanged; when the first pressure information is lower than the preset bypass working pressure range, the first bypass pipeline section is controlled to start working; when the first pressure information is higher than the preset bypass working pressure range, the first bypass pipeline section is controlled to stop working; When the third pressure information is within the preset bypass working pressure range, the second bypass pipeline section is controlled to maintain the working state unchanged; when the third pressure information is lower than the preset bypass working pressure range, the second bypass pipeline section is controlled to start working; when the third pressure information is higher than the preset bypass working pressure range, the second bypass pipeline section is controlled to stop working.

5. A multi-stage cold storage method according to claim 2, characterized in that: The cold storage pipeline section further includes a flow protector, a fourth temperature sensor and a fifth temperature sensor which are electrically connected to the controller respectively, the fourth temperature sensor is arranged on the connecting pipeline between the second output end of the first evaporator and the second input end of the second evaporator, the fifth temperature sensor is arranged on the connecting pipeline between the second output end of the second evaporator and the water pump, and the flow protector is arranged on the connecting pipeline between the output end of the cold storage tank and the second input end of the first evaporator; The controlling the first refrigeration unit, the second refrigeration unit and the cold storage pipeline part to start working further includes: When the flow protector is disconnected, the first compressor and the second compressor are controlled to stop, and a flow cut-off alarm instruction is output; When the flow protector is turned on, real-time fourth temperature information fed back by the fourth temperature sensor and real-time fifth temperature information fed back by the fifth temperature sensor are obtained, and a preset protection action temperature and a preset protection reset temperature are obtained; When the fourth temperature information is less than the preset protection action temperature, the first compressor is controlled to stop and a low temperature alarm instruction is output; when the fourth temperature information is greater than or equal to the preset protection reset temperature, the first compressor is controlled to maintain the original working state unchanged and an alarm reset instruction is output; When the fifth temperature information is less than the preset protection action temperature, the second compressor is controlled to shut down and a low temperature alarm instruction is output; when the fifth temperature information is greater than or equal to the preset protection reset temperature, the second compressor is controlled to maintain the original working state unchanged and an alarm reset instruction is output.

6. A chiller capable of multi-stage cold storage, characterized in that: The chiller capable of multi-stage cold storage adopts the multi-stage cold storage method as described in any one of claims 1 to 5 to realize working control, and the chiller capable of multi-stage cold storage includes a cold storage box, a controller, a cold storage pipeline part, a first refrigeration unit and a second refrigeration unit; the other side of the cold storage box is used to transport the cold source to the end; one side of the cold storage box, the first refrigeration unit and the second refrigeration unit are connected end to end in sequence through the cold storage pipeline part; the cold storage pipeline part includes a third temperature sensor electrically connected to the controller, and the third temperature sensor is arranged on the connecting pipeline between the output end of one side of the cold storage box and the second input end of the first refrigeration unit; the first refrigeration unit includes a first compressor electrically connected to the controller, and the second refrigeration unit includes a second compressor electrically connected to the controller.

7. A chiller capable of multi-stage cold storage according to claim 6, characterized in that: The cold storage pipeline section also includes a flow protector, a water pump, a fourth temperature sensor and a fifth temperature sensor which are electrically connected to the controller respectively; the second output end of the second refrigeration unit is connected to the input end on one side of the cold storage tank through the water pump, and the fifth temperature sensor is arranged on the connecting pipeline between the second output end of the second refrigeration unit and the water pump; the flow protector is arranged on the connecting pipeline between the output end on one side of the cold storage tank and the second input end of the first refrigeration unit; the fourth temperature sensor is arranged on the connecting pipeline between the second output end of the first refrigeration unit and the second input end of the second refrigeration unit.

8. The chiller capable of multi-stage cold storage according to claim 6, characterized in that: The second refrigeration unit has the same structure as the first refrigeration unit; the first refrigeration unit further includes a first evaporator, a first condenser, a first filter, a first expansion valve, and a first condensing fan, a first pressure sensor, a first temperature sensor, a second pressure sensor, and a second temperature sensor electrically connected to the controller; the first evaporator, the first compressor, the first condenser, the first filter, and the first expansion valve are sequentially connected end to end to form a first refrigeration cycle; the first temperature sensor and the first pressure sensor are arranged on the connecting pipe between the first compressor and the first condenser; The second temperature sensor and the second pressure sensor are arranged on a connecting pipeline between the first evaporator and the first compressor.

9. A chiller capable of multi-stage cold storage according to claim 8, characterized in that: The first refrigeration unit also includes a first bypass pipeline portion electrically connected to the controller, one end of the first bypass pipeline portion is connected to the connecting pipeline between the first compressor and the first condenser, and the other end of the bypass pipeline portion is connected to the first output end of the first evaporator.

10. The cold water chiller capable of storing cold according to claim 6, characterized in that: A diffuser and a flow equalizer are arranged in the cold storage box, the second output end of the evaporator is connected to the diffuser through an input end on one side of the cold storage box, and the output end of the flow equalizer is connected to the second input end of the evaporator through an output end on one side of the cold storage box.

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