A secondary pump cooling system for the end of a data center and its usage method

Abstract

The present invention relates to a secondary pump cooling system at the end of a data center, comprising a plurality of end secondary pump cooling devices, a plurality of cold source supply devices, a water supply pipe network, a water return pipe network, and a one-way pressure relief module. By arranging the secondary pump in the end cooling device and realizing the adaptive control of cooling supply on the load side through the adjustment of the secondary pump speed in the end secondary pump cooling device, and by adjusting the speed of the primary pump to make the pressure difference between the water supply and return pipe networks close to zero, the automatic control of cooling supply on the cold source side is realized. The end secondary pump cooling device of the present invention is adaptively adjusted, the pressure difference between the water supply and return pipe networks is close to zero, the system has low energy consumption, and the cold source side and the load side are easy to expand and maintain.

Description

Technical Field

[0001] The present invention relates to the field of heating, ventilation and air conditioning (HVAC) for data centers, and particularly to a secondary pump cooling system for the end of a data center. Background Art

[0002] Currently, large data centers mostly use chilled water systems for cooling. The energy consumption of traditional chilled water systems accounts for about 50%-60% of the overall energy consumption of the data center. As the system scale expands, the proportion of the energy consumption for water system transportation also continuously increases. The main energy-consuming equipment in the air conditioning system is water pumps, air handling units, and chillers, especially the water pumps account for a relatively large proportion. Optimizing the distribution of the air conditioning water system and reducing the energy consumption of water pumps are of extremely important significance for the energy conservation of data centers.

[0003] Existing chilled water systems for data centers generally use water valves to regulate the flow rate. The pressure difference between the supply and return water pipe networks is generally above 100 KPa. Such a system requires high energy consumption, and uneven end pressures are likely to cause insufficient cooling for some equipment. Summary of the Invention

[0004] In order to solve the problems in the existing chilled water system that the energy consumption required to maintain the pressure difference between the supply and return water pipe networks is high, and uneven end pressures are likely to cause insufficient cooling for some equipment. The present invention proposes a secondary pump cooling system for the end of a data center. By setting the secondary pumps in the end cooling devices and adjusting the rotational speeds of the secondary pumps in the end secondary pump cooling devices, load-side cooling adaptive control is achieved. By adjusting the rotational speeds of the primary pumps in each cold source supply device, the pressure difference between the supply and return water pipe networks is made close to zero to achieve automatic control of cold source-side cooling.

[0005] The present invention uses a one-way pressure relief template and a cold storage device to replace the balance pipe of the traditional secondary pump system, enabling the reliability of the secondary pump system to meet the requirements of the data center while achieving the purpose of system energy conservation and consumption reduction.

[0006] The technical solution of the embodiment of the present invention is as follows:

[0007] A secondary pump cooling system for the end of a data center includes a plurality of end secondary pump cooling devices, a plurality of cold source supply devices, a supply water pipe network, a return water pipe network, and a one-way pressure relief module;

[0008] The terminal secondary pump cooling device is partially or wholly a terminal air handling unit including a housing, a water pump, a check valve, a temperature sensor, a controller, a finned tube cooler, and a fan; the temperature sensor is installed on the supply and return air ducts of the terminal secondary pump cooling device; the controller of the terminal secondary pump cooling device adjusts the supply air temperature of the terminal secondary pump cooling device by adjusting the rotational speed of the water pump of the terminal secondary pump cooling device, and adjusts the return air temperature of the terminal secondary pump cooling device by adjusting the rotational speed of the fan of the terminal secondary pump cooling device; the water pump of the terminal secondary pump cooling device is built inside the housing or installed on the inlet pipe or outlet pipe outside the housing.

[0009] The cold source supply device at least includes a water pump, a check valve, a differential pressure sensor, a controller, and a chiller; the differential pressure sensor is installed on the supply water pipe and the return water pipe; the controller of the cold source supply device adjusts the rotational speed of the water pump of the cold source supply device so that the pressure difference between the supply water network and the return water network is close to zero.

[0010] The one-way pressure relief module is connected between the supply water network and the return water network close to the terminal secondary pump cooling device and is composed of a pipeline and a check valve.

[0011] The technical effects of the present invention are as follows:

[0012] 1. Adaptive control of cooling supply on the load side is achieved through the adjustment of the rotational speed of the water pump and the rotational speed of the fan of the terminal secondary pump cooling device, enabling the system to automatically adjust the chilled water flow rate and cooling load according to the heat load on the load side; the controller adjusts the supply air temperature by adjusting the rotational speed of the water pump and adjusts the return air temperature by adjusting the rotational speed of the fan.

[0013] 2. By adjusting the rotational speed of the primary pump of the cold source supply device, the pressure difference between the chilled water supply pipe network and the chilled water return pipe network near the terminal air conditioner is close to zero. Since the pressure difference between the supply and return pipe networks is close to zero, the interference between all water pumps is small, and all water pumps in the system operate stably at a high efficiency state and are not affected by other water pumps in the system. Group control is achieved through the interconnection between the controllers of the cold source supply devices.

[0014] 3. The method of adjusting the terminal cooling load by setting the rotational speeds of the secondary pump and the fan in the terminal secondary pump cooling device is used to replace the conventional method of adjusting the terminal cooling load with a water pump + electric valve. The main supply and return water pipe networks do not need to maintain a large pressure difference, which can enable both the primary pump and the secondary pump to operate at a low load, with high water pump efficiency and more energy-saving than the traditional solution.

[0015] 4. Since the pressure difference between the supply and return water pipe networks of the secondary pump cooling system at the end of this data center is close to zero, it is easy to compatibly connect the same equipment of different specifications on both the cold source supply side and the load side. It can be flexibly expanded, and two sets of secondary pump cooling systems at the end of the data center can be seamlessly paralleled and used as spares for each other.

[0016] 5. After the chilled water system pipe networks on the cold source side are paralleled between two buildings adopting the secondary pump cooling system at the end, when the cold source supply of one building is insufficient or fails, the cold source supply device of the other building automatically loads.

[0017] The present invention realizes the automatic control of the entire system and the parallel operation of the cold source supply device and the water storage cooling device between systems as spares through equipment-level control, ensuring the reliability of the system. Brief Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the system of the first embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of the indirect evaporative chiller in the third embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the system of the fourth embodiment of the present invention;

[0021] Figure 4 It is a schematic diagram of the system of the fifth embodiment of the present invention;

[0022] Figure 5 It is a schematic diagram of the system of the sixth embodiment of the present invention;

[0023] Figure 6 It is a schematic diagram of the system of the seventh embodiment of the present invention;

[0024] Figure 7 It is a schematic diagram of the system of the eighth embodiment of the present invention;

[0025] Cold source supply device 110, primary pump 111, chiller 112, indirect evaporative chiller unit 113, water supply pipe network 200; secondary pump cooling device 310; secondary pump 311; terminal air handling unit 312; water return pipe network 400; one-way pressure relief module 500; water storage cooling device 600; cold storage tank 611, cold release pump 612, chiller unit 613, cold storage pump 614, three-way valve 615 for cold storage device. Detailed Embodiments

[0026] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0027] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] Application background:

[0030] In a data center, generally, at least several hundred cabinets are contained on one floor of a data center, and several servers are arranged in the cabinets. According to the power selection of the servers in a single cabinet and the operating load of the servers, the heat generation of each cabinet is different, and the required cooling source size is different. Generally, the cabinet power is 2kW, 3KW, 4KW, 6KW, 8KW, 12KW, etc., and the operating load can vary from 0 to 100%, resulting in a huge difference in the actual load between cabinets. Thus, the required cooling sources also differ greatly. Using the traditional primary pump water system architecture design can no longer meet the requirements of adjusting the data center water system according to the cooling source demand. In the existing chilled water system solutions for data centers, the pressure difference between the supply and return pipe networks is generally above 100KPa. In this way, the supply water can enter the load side due to the pressure difference, and the flow rate into the terminal air handling unit on the load side is adjusted by adjusting the valve before entering the load side. The energy consumption required for the water system to maintain the pressure difference is relatively high, and the uneven terminal pressure easily causes insufficient cooling for some equipment. In addition, it is difficult to expand the load side and the cooling source side. It is basically impossible to operate the chilled water systems on the cooling source side between two buildings in parallel as a backup, and it is difficult to achieve automatic control and ensure the reliability of the system.

[0031] Both the water supply pipe network and the water return pipe network involved in this article are closed pipe networks.

[0032] The implementation background of the embodiments in this article is in the application scenario of a data center. Generally, the cooling source configuration is at least configured according to the N+1 architecture, that is, to meet the maximum cooling load of the data center design, N chillers and M terminals are required. At least N+1 chillers and M+1 terminals are configured in the system.

[0033] Embodiment Example 1:

[0034] As Figure 1 shown, the secondary pump system at the end of the data center in this embodiment example includes several end secondary pump cooling devices 310, several cold source supply devices 110, a water supply network 200, a water return network 400, and a one-way pressure relief module 500.

[0035] Several end secondary pump cooling devices are connected to one side of the water supply network and the water return network, generally set in the end air-conditioned rooms of the data center or near the cabinets, and several end secondary pump cooling devices are relatively concentrated together; several cold source supply devices are connected to the other side of the water supply network and the water return network, generally set in the chiller unit equipment room of the data center, or in the cooling tower equipment room or on the roof, and several cold source supply devices are relatively concentrated together.

[0036] Each end secondary pump cooling device 310 includes at least one water pump 311 (the water pump set here is called a secondary pump in the HVAC industry), one chilled water end air handling unit 312, a check valve (set at the outlet of the water pump 311, not marked in the figure), a temperature sensor (not marked in the figure), and a controller (not marked in the figure); in each end secondary pump cooling device 310, the output head of the secondary pump 311 corresponds to the head required to overcome the resistance of the end air handling unit 312; the controller adjusts the cooling load by adjusting the water pump speed. The water pump 311 and the check valve (set at the outlet of the water pump 311) isolate several end secondary pump cooling devices from each other and do not affect each other.

[0037] The end secondary pump cooling device 310 makes the inlet and outlet pressures of the entire end secondary pump cooling device the same through the direct pressure matching between the secondary pump 311 and the end air handling unit 312. The secondary pump can adjust the water flow rate of the inlet according to the requirements of the end air handling unit. When the supply air temperature of the end air handling unit is greater than the set value, the water flow rate is increased; when the supply air temperature of the end air handling unit is less than the design value, the water flow rate is decreased.

[0038] The end secondary pump cooling device 310 can be a decentralized system composed of a secondary pump and an end air handling unit, or can be integrally designed. The decentralized end cooling device occupies a large space and is easy to re-update the configuration of each component; the integrated end secondary pump cooling device occupies a small space, is more convenient to use in the data center, and improves the space utilization rate of the data center.

[0039] Preferably, the end secondary pump cooling device 310 is a system with an integrated design, including a housing, a water pump 311, a check valve, a temperature sensor, a controller, a surface cooler, and an end air handling unit with a fan. The secondary pump is integrated in the end air handling unit, with a small volume, and the water flow rate can be dynamically adjusted according to the end demand through this secondary pump.

[0040] The water pump of the terminal secondary pump cooling device in this embodiment is built inside the housing of the secondary pump cooling device or installed on the water inlet pipe or the water outlet pipe.

[0041] In the terminal secondary pump cooling device, the controller adjusts the water supply temperature by regulating the rotational speed of the water pump, and adjusts the return air temperature by regulating the rotational speed of the fan. Through such adjustment, the terminal secondary pump cooling device automatically adjusts the chilled water flow rate and cooling load according to the heat load on the load side, realizing refined control of a single terminal secondary pump cooling device, and making the entire terminal secondary pump cooling system of the data center more energy-efficient.

[0042] For example: The control signal of the terminal air handling unit is the supply and return air temperatures. The set value of the supply air temperature is 23 °C. When the supply air temperature > 23 °C, the frequency of the secondary pump is increased; when the supply air temperature < 23 °C, the frequency of the secondary pump is decreased; finally, the supply air temperature is maintained stable at 23 °C. The set value of the return air temperature is 33 °C. When the return air temperature > 33 °C, the fan frequency of the terminal air handling unit is increased; when the return air temperature < 33 °C, the fan frequency of the terminal air handling unit is decreased; finally, the return air temperature is maintained stable at 33 °C.

[0043] The various cold source supply devices 110 are arranged in parallel and connected to the water supply network and the water return network. The cold source supply device 110 at least includes a water pump 111 (the water pump here is generally called the primary pump), a check valve (installed at the outlet of the water pump 111), a differential pressure sensor, a controller (not marked in the figure), and a chiller 112; the primary pump 111 is controlled by the controller of the cold source supply device, so that the pressure difference between the water supply network and the water return network near the one-way pressure relief module 500 is close to zero. Through the controller of the cold source supply device, each cold source supply device has little impact on the water supply and return networks, facilitating the addition, maintenance, and removal of cold source supply devices. The water pump 111 and the check valve (installed at the outlet of the water pump 111) isolate several cold source supply devices from each other without mutual influence.

[0044] The differential pressure sensor of the cold source supply device in this embodiment is installed on the water supply network and the water return network. The rotational speed of the primary pump is adjusted by detecting the pressure difference between the water supply and return networks near the one-way pressure relief module through the differential pressure sensor.

[0045] Each individual cold source supply device 110 realizes that the pressure difference between the water supply and return networks is positive and close to zero through the controller of its own cold source supply device, making each cold source supply device 110 relatively independent and non-interfering with each other, realizing the group control of cold source supply devices. When the system needs to be expanded, only new cold source supply devices need to be directly connected, without additional auxiliary configuration conditions, and the system expansion is simple and easy to operate.

[0046] Among multiple cold source supply devices, the automatic startup and shutdown, load increase and decrease of the chillers are realized through group control. All cold source supply devices coordinate with each other to make the overall operation in an energy-saving state.

[0047] Specific control cases are as follows:

[0048] 1) Dynamically adjust the frequency of the primary pump in the cold source supply device, that is, adjust the rotational speed of the water pump, by detecting the pressure difference of the supply and return water pipe networks near the one-way pressure relief module in real time.

[0049] 1a) When the pressure of the chilled water supply pipe network > the pressure of the chilled water return pipe network (pressure difference > 0 KPa), the frequency of the primary pump inverter is lowered, that is, the rotational speed of the water pump is lowered;

[0050] 1b) When the pressure of the chilled water supply pipe network < the pressure of the chilled water return pipe network (pressure difference < 0 KPa), the frequency of the primary pump inverter is increased, that is, the rotational speed of the water pump is increased;

[0051] 2) The group control dynamically adjusts the startup and shutdown, load increase and decrease of multiple cold source supply devices by detecting the temperature of the supply and return water pipe networks near the one-way pressure relief module in real time.

[0052] 1a) When the temperature of the chilled water supply pipe network > the set value, all running cold source supply devices automatically load. When all running cold source supply devices are automatically loaded to full load and the temperature of the chilled water supply pipe network still > the set value, a new cold source supply device is automatically started through group control, and the loading starts from the minimum load of the chiller of this cold source supply device until the temperature of the chilled water supply pipe network is equal to the set value; when the temperature of the chilled water supply pipe network reaches the set value, the control of the cold source supply device is used for secondary group control to match the operating parameters of each cold source supply device, so that all started and running cold source supply devices coordinate with each other to make the overall operation in an energy-saving state;

[0053] 1b) When the temperature of the chilled water supply pipe network < the set value, all running cold source supply devices automatically unload. When all running cold source supply devices are automatically unloaded to the minimum load of the chiller and the temperature of the chilled water supply pipe network still < the set value, one of the cold source supply devices is automatically shut down through group control until the temperature of the chilled water supply pipe network is equal to the set value; when the temperature of the chilled water supply pipe network reaches the set value, the control of the cold source supply device is used for secondary group control to match the operating parameters of each cold source supply device, so that all started and running cold source supply devices coordinate with each other to make the overall operation in an energy-saving state;

[0054] In engineering, when the absolute value of the pressure difference is not greater than 5 KPa or 10 KPa or 20 KPa, it is considered that the pressure difference is close to zero. In engineering control, generally, the rotational speed of the water pump is adjusted by adjusting the frequency of the water pump.

[0055] The cold source supply device 110 can be a decentralized system composed of a primary pump, a controller, and a chilled water mechanism, or it can be integrally designed. The decentralized cold source supply device occupies a large space and is easy to reconfigure; the integrated cold source supply device occupies a small space, is more convenient to use in the data center, and improves the space utilization rate of the data center.

[0056] The one-way pressure relief module 500 is connected between the water supply network and the water return network near the end, and is composed of a pipeline and a check valve. At least one one-way pressure relief module is provided in the embodiment. Preferably, 2 one-way pressure relief modules are provided in the secondary pump cooling system at the end of the data center, as Figure 1 shown.

[0057] For example: when the pressure of the chilled water supply network near the one-way pressure relief module is higher than that of the chilled water return network (pressure difference > 15 KPa), the check valve on the bypass pipe automatically opens.

[0058] By using the one-way pressure relief module to replace the bypass pressure difference valve in the existing system, the controllable pressure difference between the supply and return water networks is reduced, from the traditional pressure difference of the order of 100 KPa to the pressure difference of the order of 10 - 20 KPa, reducing the energy consumption for maintaining the pressure difference of the system; by dynamically adjusting the speed of the primary pump according to the pressure difference between the supply and return water networks and the one-way pressure relief module automatically relieving pressure, the pressure difference between the supply and return water networks is made positive and close to zero.

[0059] In the first embodiment, the secondary pump is arranged in the end cooling device, and the load-side cooling adaptive control is realized by adjusting the speed of the secondary pump in the end secondary pump cooling device. The automatic control of the cold source-side cooling is realized by adjusting the speed of the primary pump so that the pressure difference between the supply and return water networks is close to zero. The end secondary pump cooling device of the present invention has adaptive adjustment, the pressure difference between the supply and return water networks is close to zero, the system energy consumption is low, and the cold source side and the load side are easy to expand and maintain.

[0060] The second embodiment:

[0061] The difference between the second embodiment and the first embodiment is that part or all of the chiller 112 in the second embodiment is an indirect evaporative chiller 113. The indirect evaporative chiller mainly exchanges heat between outdoor air and return water, and there is also a situation of outdoor air water evaporation during this heat exchange process, and the temperature of the return water in the chiller is reduced through air heat exchange and water evaporation. By selecting part or all of the indirect evaporative chillers, the entire end secondary pump cooling system of the data center is more energy-efficient than the traditional pure mechanical refrigeration chiller.

[0062] The third embodiment:

[0063] The difference between the third embodiment and the second embodiment is that the indirect evaporative chiller 113 includes a closed cooling tower, a chilled water pump, and a mechanical refrigeration module, as Figure 2As shown. The mechanical refrigeration module is preferably a magnetic levitation chiller.

[0064] Preferably, the indirect evaporative chiller of this embodiment includes an equipment housing, a controller, a water inlet pipe, a fan, a heat exchanger, a water outlet pipe, a spray module, a sump, a water pump, a check valve, a differential pressure sensor, and a mechanical refrigeration module; the mechanical refrigeration module includes a compressor, an evaporator, and a condenser.

[0065] Through integrated molding and assembly, the entire cold source supply device is more compact and has a small footprint; at the same time, due to the compact design, the distance between the various units of the indirect evaporative chiller becomes shorter, reducing the waste of cold source for heat transfer between units and also reducing the energy consumption of water transportation.

[0066] The indirect evaporative chiller of this embodiment is preferably composed of a variable-frequency magnetic levitation chiller and an indirect evaporation module. The supply water temperature is preferably selected between 16 - 19 °C, and the return water temperature is preferably selected between 26 - 30 °C. Compared with the conventional, the mechanical refrigeration part using the magnetic levitation chiller is more energy-efficient. By using a higher supply water temperature and return water temperature, the COP of the indirect evaporative chiller increases. The system can save about 20 - 30% of energy compared with the traditional working condition of 7 °C supply water and 12 °C return water; the combination of the variable-frequency magnetic levitation chiller and the indirect evaporation module makes the system more widely applicable, not only suitable for dry and semi-dry regions, but also adaptable to humid regions.

[0067] Embodiment Four:

[0068] The difference between Embodiment Four and Embodiments One, Two, and Three is that several water thermal energy storage devices are also provided between the water supply pipe network and the water return pipe network near the end secondary pump cooling device. The system schematic diagram is as Figure 3 shown. The water thermal energy storage device includes a thermal energy storage tank, an electric valve, a thermal energy storage device temperature sensor (not shown in the figure), and a thermal energy storage device controller (not shown in the figure). When the cold source supply device is powered off or fails, the end secondary pump cooling device obtains cold water from the water thermal energy storage device and injects the return water into the water thermal energy storage device.

[0069] When the temperature of the thermal energy storage device > the set value of the thermal energy storage temperature, thermal energy storage starts. The water in the water supply pipe network 200 enters the water thermal energy storage device 600, passes through the check valve and enters the water return pipe network 400 to ensure that the temperature of the thermal energy storage device ≤ the set value.

[0070] When the temperature of the thermal energy storage device ≤ the set value of the thermal energy storage temperature, it enters the standby or heat release mode;

[0071] When the temperature of the water supply pipe network 200 > the set value of the supply water temperature, this water thermal energy storage device releases heat. The heat release is achieved as follows: The water in the water return pipe network 400 passes through the electric valve and enters the water thermal energy storage device 600, and then enters the water supply pipe network 200, making the temperature of the water supply pipe network 200 equal to the set value, as Figure 4 shown.

[0072] When the temperature of the water supply network 200 ≤ the set value of the water supply temperature, the water energy storage device determines whether to enter the standby or energy storage mode by judging the temperature of the energy storage device and the set value of the energy storage temperature.

[0073] By setting a water energy storage device in the secondary pump cooling system at the end of the data center, the continuous cooling demand is met. When the system cooling supply is insufficient, the stored cold is released, and when the conditions for energy storage are met, energy storage is carried out.

[0074] Example 5:

[0075] When comparing Example 5 with Example 4 (as Figure 4 shown), the difference is that a water energy storage device is arranged in parallel on the cold water outlet pipeline of the cold source supply device 110. The water energy storage device includes a cold storage tank, an electric valve, a temperature sensor of the energy storage device (not shown in the figure), and a controller of the energy storage device (not shown in the figure). When the cold source supply device is powered off or fails, the cold source supply device obtains cold water from the water energy storage device and injects the return water into the water energy storage device.

[0076] When the temperature of the energy storage device > the set value of the energy storage temperature, energy storage starts. By controlling the electric valve (three-way valve), the water discharged from the cold source supply device 110 enters the water energy storage device 600 to ensure that the temperature of the energy storage device ≤ the set value.

[0077] When the temperature of the energy storage device ≤ the set value of the energy storage temperature, it enters the standby or cold release mode;

[0078] When the temperature of the water supply network 200 > the set value of the water supply temperature, the water energy storage device releases cold; the water in the return water network 400 enters the water energy storage device 600 after passing through the cold source supply device 110 and enters the water supply network 200 through the electric valve (three-way valve) to ensure that the temperature of the water supply network 200 is equal to the set value.

[0079] When the temperature of the water supply network 200 ≤ the set value of the water supply temperature, the water energy storage device enters the standby or energy storage mode.

[0080] The difference from Example 4 is that the energy storage device in Example 5 can also be applied to the cold source supply device for natural cold source cooling. When the natural cold source supply is insufficient, the energy storage device releases cold to make up for the deficiency of natural cold source cooling, thereby solving the problem that the natural cold source in the prior art is greatly affected by the ambient temperature and is prone to insufficient cooling under high temperature conditions.

[0081] When the water energy storage device in this embodiment is connected to a general mechanical refrigeration chiller, it can increase the cooling supply of the mechanical refrigeration chiller to store cold energy in the water energy storage device during the low electricity consumption period of the power grid. Specifically, it can store cold energy at 4-8°C and release cold energy during the high electricity consumption period of the power grid, thereby reducing the electricity consumption during the peak period, achieving the effect of peak shifting and valley filling, and saving the energy of the entire system.

[0082] Embodiment Six:

[0083] When comparing Embodiment Six with Embodiment Four and Embodiment Five (as Figure 5 shown), the difference is that a water energy storage device is provided near the cold source supply device on the water supply pipe network and the water return pipe network. The water energy storage device includes a cold storage tank 611, a cold release pump 612, a chiller 613, a cold storage pump 614, cold storage device pipes, a cold storage device three-way valve 615, a cold storage device temperature sensor (not shown in the figure), and a cold storage device controller (not shown in the figure). When the cold source supply device is powered off or fails, the water supply pipe network obtains cold water from the water energy storage device and injects the return water into the water energy storage device.

[0084] When the temperature of the cold storage device > the set value of the cold storage temperature, cold storage starts. The return water is sent into the cold storage tank 611 through the cold storage pump 614 and the chiller 613 to ensure that the temperature of the cold storage device ≤ the set value.

[0085] When the temperature of the cold storage device ≤ the set value of the cold storage temperature, it enters the standby or cold release mode;

[0086] When the temperature of the water supply pipe network 200 > the set value of the water supply temperature, the water energy storage device releases cold; the water in the water return pipe network 400 enters the cold storage tank 611 through the cold release pump 612 and the check valve, passes through the cold storage device three-way valve 615, and enters the water supply pipe network 200 to inject cold water into the water supply pipe network 200. By adjusting the opening of the cold storage device three-way valve 615, ensure that the temperature of the water supply pipe network 200 is equal to the set value.

[0087] When the temperature of the water supply pipe network 200 ≤ the set value of the water supply temperature, the water energy storage device enters the standby or cold storage mode.

[0088] This cold storage system operates energy-efficiently by setting the operating conditions of the chiller. It meets the demand for uninterrupted cooling or performs full-load cold storage using the peak-valley electricity price difference.

[0089] The difference between Embodiment Six and Embodiment Four and Embodiment Five is that: Embodiment Six is provided with a chiller 613 and a cold storage pump 614, which can actively store cold when the cold storage capacity is insufficient; Embodiment Six is provided with a cold release pump 612, which can actively release cold.

[0090] The cold storage device 600 can be set with its components decentralized or integrated. Compared with the decentralized setting, the integrated cold storage device 600 saves more space and is more suitable for use in a data center.

[0091] In this embodiment, it is preferable that the cold storage water temperature is 4 - 8°C, rather than adopting the common water cold storage at 10 - 12°C. This can reduce the volume and floor area of the cold storage tank under the same cold storage requirements, and reduce the initial investment.

[0092] Embodiment Seven:

[0093] Embodiment Seven is another preferred embodiment (as Figure 6 shown). The difference is that a water cold storage device is provided near the end secondary pump cooling device on the water supply pipe network and the water return pipe network. The water cold storage device includes a cold storage tank 611, a cold release pump 612, a chiller 613, a cold storage pump 614, cold storage device pipes, a cold storage device three-way valve 615, a cold storage device temperature sensor (not shown in the figure), and a cold storage device controller (not shown in the figure). When the cold source supply device is powered off or fails, the water supply pipe network obtains cold water from the water cold storage device and injects the return water into the water cold storage device.

[0094] The cold storage device 600 can be set with its components decentralized or integrated. Compared with the decentralized setting, the integrated cold storage device 600 saves more space and is more suitable for use in a data center.

[0095] In this embodiment, it is preferable that the cold storage water temperature is 4 - 8°C, rather than adopting the common water cold storage at 10 - 12°C. This can reduce the volume and floor area of the cold storage tank under the same cold storage requirements, and reduce the initial investment.

[0096] Compared with Embodiment Six, the difference is that the water cold storage device can preferably be placed on the end load side, with a more sensitive response.

[0097] Embodiment Eight:

[0098] As Figure 7As shown in the figure, the implementation background of this embodiment is in the data center application scenario. Generally, the cold source configuration is at least configured according to the N+1 architecture, and the terminal is configured according to the M+1 architecture; that is, to meet the maximum cooling load designed for the data center, N chillers and M terminals are required. In the system, at least N+1 chillers and M+1 terminals are configured. In this implementation example, the cold source supply device and the water-cooled energy storage device between two systems a and b are in parallel operation as backups for each other. After the chilled water system pipe networks between two buildings adopting the secondary pump cooling system at the data center terminal are connected in parallel through the supply connection pipe and the return connection pipe, when the cold source supply of one building b is insufficient or fails and the cooling supply of building a is sufficient, the temperature of the supply and return pipe networks is detected in real time and the on / off and load addition and subtraction of the cold source supply device of building a are dynamically adjusted through group control.

[0099] When the cold source supply of one building b is insufficient or fails and the cooling supply of building a is sufficient:

[0100] When the temperature of the chilled water supply pipe network > the set value, a new cold source supply device of building a is automatically turned on through group control, and the load is increased starting from the minimum load of the chiller of this cold source supply device until the temperature of the chilled water supply pipe network is equal to the set value;

[0101] When the cooling supplies of building a and building b are sufficient:

[0102] When the temperature of the chilled water supply pipe network < the set value, all the operating cold source supply devices of building a are automatically unloaded. When all the operating cold source supply devices of building a are automatically unloaded to the minimum load of the chiller and the temperature of the chilled water supply pipe network is still < the set value, one cold source supply device of building b is automatically turned off through group control until the temperature of the chilled water supply pipe network is equal to the set value.

[0103] In this embodiment, as Figure 7 shown, the secondary pump cooling systems at the data center terminals in the two buildings can be interconnected in parallel like the cold source supply devices through the pipe network.

[0104] In the existing chilled water system solutions in data centers, the pressure difference between the supply and return pipe networks is generally above 100 KPa, and the energy consumption required to maintain the pressure difference is relatively high. The uneven terminal pressure is likely to cause insufficient cooling supply for some equipment. It is basically impossible or requires higher energy consumption for the chilled water systems on the cold source side between two existing conventional buildings to operate in parallel as backups for each other, and the stability of the system is affected.

[0105] After the chilled water system pipe networks between two buildings adopting the present secondary pump cooling system at the end are connected in parallel, when the chilled water source supply of one building is insufficient or fails, the chilled water source supply device of the other building automatically loads, and the pressure difference between the supply and return pipe networks is always close to zero, without affecting the stability of the system. Through equipment-level control, automatic control of the entire system and parallel operation with mutual backup of the chilled water source supply device and the water chilled storage device between systems are achieved, ensuring the reliability of the chilled water source supply.

[0106] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0107] The above embodiments only represent the preferred implementation modes of the present invention, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A secondary pump cooling system for the end of a data center, characterized in that: the secondary pump cooling system for the end of the data center includes a number of end secondary pump cooling devices, a number of cold source supply devices, a water supply pipe network, a water return pipe network, and a one-way pressure relief module; part or all of the end secondary pump cooling devices are end air handling units including a housing, a water pump, a check valve, a temperature sensor, a controller, a surface cooler, and a fan; the temperature sensor is installed on the supply and return air channels of the end secondary pump cooling device; the controller of the end secondary pump cooling device adjusts the water supply temperature of the end secondary pump cooling device by adjusting the water pump speed of the end secondary pump cooling device, and adjusts the return air temperature of the end secondary pump cooling device by adjusting the fan speed of the end secondary pump cooling device; the water pump of the end secondary pump cooling device is built inside the housing or installed on the water inlet pipe or the water outlet pipe outside the housing; the cold source supply device at least includes a water pump, a check valve, a differential pressure sensor, a controller, and a chiller; the differential pressure sensor is installed on the water supply pipe and the water return pipe; the controller of the cold source supply device adjusts the water pump speed of the cold source supply device so that the differential pressure between the water supply pipe network and the water return pipe network is close to zero; the one-way pressure relief module is connected between the water supply pipe network and the water return pipe network near the end secondary pump cooling device and is composed of a pipe and a check valve; a water thermal energy storage device is provided near the cold source supply device on the water supply pipe network and the water return pipe network, and a water thermal energy storage device is provided near the end secondary pump cooling device on the water supply pipe network and the water return pipe network. The water thermal energy storage device partially or wholly includes a cold storage tank, an electric valve, a temperature sensor, a cold release pump, a cold storage pump, a chiller, and a controller; when the cold source supply device is powered off or fails, the water thermal energy storage device pumps the return water from the water return pipe network and injects cold water into the water supply pipe network; the cold storage water temperature of the water thermal energy storage device is 4 - 8 °C.

2. The secondary pump cooling system for the end of a data center according to claim 1, characterized in that: part or all of the cold source supply device is an indirect evaporative chiller; the indirect evaporative chiller includes an equipment housing, a controller, a fan, a heat exchanger, a spray module, a sump, a water pump, a check valve, a differential pressure sensor, and a mechanical refrigeration module; the mechanical refrigeration module includes a compressor, an evaporator, and a condenser.

3. The secondary pump cooling system for the end of a data center according to claim 1, characterized in that: the cold source supply devices are interconnected through the controller of the cold source supply device to achieve group control.

4. The secondary pump cooling system for the end of a data center according to claim 1, characterized in that: a water thermal energy storage device is provided on the water supply pipe network and the water return pipe network near the end secondary pump cooling device; the water thermal energy storage device partially or wholly includes a cold storage tank, an electric valve, a temperature sensor, and a controller. When the cold source supply device is powered off or fails, the secondary pump cooling device at the end obtains cold water from the water thermal energy storage device and injects the return water into the water thermal energy storage device.

5. The data center secondary pump cooling system according to claim 1, characterized in that: a water thermal energy storage device is arranged in parallel on the cold water outlet pipeline of the cold source supply device; the water thermal energy storage device partially or wholly includes a cold storage tank, an electric valve, a temperature sensor, and a controller; when the cold source supply device is powered off or fails, the cold source supply device obtains cold water from the water thermal energy storage device and injects the return water into the water thermal energy storage device; the temperature of the cold water stored in the water thermal energy storage device is 4-8 °C.

6. A method for using the data center secondary pump cooling system according to claim 1, characterized in that: the data center secondary pump cooling system is adopted in two adjacent buildings, and the two data center secondary pump cooling systems are connected in parallel through pipelines, so that the cold source supply devices and the water thermal energy storage devices of the two data center secondary pump cooling systems are used as backups for each other; the data center secondary pump cooling system includes a plurality of secondary pump cooling devices at the end, a plurality of cold source supply devices, a water supply network, a return water network, a one-way pressure relief module, and a water thermal energy storage device; part or all of the secondary pump cooling devices at the end are end air handling units including a housing, a water pump, a check valve, a temperature sensor, a controller, a surface cooler, and a fan; the temperature sensor is installed on the supply and return air channels of the secondary pump cooling device at the end; the controller of the secondary pump cooling device at the end adjusts the water supply temperature of the secondary pump cooling device at the end by adjusting the water pump speed of the secondary pump cooling device at the end, and adjusts the return air temperature of the secondary pump cooling device at the end by adjusting the fan speed of the secondary pump cooling device at the end; the water pump of the secondary pump cooling device at the end is built inside the housing or installed on the water inlet pipeline or the water outlet pipeline outside the housing; the cold source supply device at least includes a water pump, a check valve, a differential pressure sensor, a controller, and a chiller; the differential pressure sensor is installed on the water supply pipeline and the return water pipeline; the controller of the cold source supply device adjusts the water pump speed of the cold source supply device so that the differential pressure between the water supply network and the return water network is close to zero; the one-way pressure relief module is connected between the water supply network and the return water network close to the secondary pump cooling device at the end and is composed of a pipeline and a check valve.

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