Fully redundant cooling units with phase-changing flow control units

Abstract

In one embodiment, the liquid cooling device includes a first cooling circuit for providing cooling liquid to a heat load and a second cooling circuit for providing cooling liquid to the heat load, wherein the first cooling circuit includes a first condenser unit, a first liquid supply line, and a first vapor return line, wherein the second cooling circuit includes a second condenser unit, a second liquid supply line, and a second vapor return line, wherein the first vapor return line and the second vapor return line are connected by an interconnection circuit. The liquid cooling device also includes a first pressure sensor connected to the first vapor return line, a second pressure sensor connected to the second vapor return line, and at least one primary cooling source controlled based on the first pressure sensor and the second pressure sensor.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to data centers. More specifically, embodiments of the present invention relate to fully redundant phase change cooling units with flow control units. Background Art

[0002] Thermal management of a data center that includes several active electronic racks is critical to ensuring proper performance of the servers and other IT equipment running in the racks. Without proper thermal management, the thermal environment within the rack may exceed the operating threshold, resulting in operational consequences (e.g., server failure, etc.). One way to manage the thermal environment is to use chilled air to cool the IT equipment. Most existing data centers are air cooled. Recently, data centers have deployed higher power density electronic racks, where higher density chips are packed more closely together to provide greater processing power. Cooling these high density racks by maintaining a proper thermal environment can be a challenge for existing cooling systems, especially as the power density of the racks continues to increase.

[0003] Existing solutions for cooling systems include phase change systems. However, such systems may not include redundant designs or may not provide full redundancy for the entire cooling system, which means including a single failure port. In addition, existing solutions may require a lot of adjustments and controls, even after the solution has been deployed. Summary of the invention

[0004] One aspect of the present disclosure provides a cooling device, which includes: a first cooling circuit, which provides cooling liquid to a heat load, wherein the first cooling circuit includes a first condenser unit, a first liquid supply pipeline and a first vapor return pipeline; a second cooling circuit, which provides cooling liquid to the heat load, wherein the second cooling circuit includes a second condenser unit, a second liquid supply pipeline and a second vapor return pipeline; an interconnection circuit, which is connected to the first vapor return pipeline and the second vapor return pipeline; a first pressure sensor, which is connected to the first vapor return pipeline; a second pressure sensor, which is connected to the second vapor return pipeline; and at least one main cooling source, which is controlled based on the first pressure sensor and the second pressure sensor.

[0005] Another aspect of the present disclosure provides a cooling system, which includes: a first cooling circuit, which provides cooling liquid to an immersion tank, wherein the first cooling circuit includes a first condenser unit, a first liquid supply pipeline and a first vapor return pipeline; a second cooling circuit, which provides cooling liquid to the immersion tank, wherein the second cooling circuit includes a second condenser unit, a second liquid supply pipeline and a second vapor return pipeline; an interconnection circuit, which is connected to the first vapor return pipeline and the second vapor return pipeline; a first pressure sensor, which is connected to the first vapor return pipeline; a second pressure sensor, which is connected to the second vapor return pipeline; and at least one main cooling source, including a fluid control valve controlled based on the first pressure sensor and the second pressure sensor.

[0006] Yet another aspect of the present disclosure provides a method for controlling a two-phase cooling distribution unit, the method comprising: receiving pressure data from a first pressure sensor connected to a first vapor return line of a first coolant distribution circuit; receiving pressure data from a second pressure sensor connected to a second vapor return line of a second coolant distribution circuit, wherein the second coolant distribution circuit operates in parallel with the first coolant distribution circuit; controlling the cooling capacity of the first coolant distribution circuit based on the pressure data from the second pressure sensor; and controlling the cooling capacity of the second coolant distribution circuit based on the pressure data from the first pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements.

[0008] Figure 1 is a system diagram of a two-phase cooling system design according to one embodiment.

[0009] Figure 2 is a system diagram of a two-phase cooling system design according to one embodiment.

[0010] Figure 3 is a system diagram of a two-phase cooling system design according to one embodiment.

[0011] Figure 4 is a system diagram of a two-phase cooling system design according to one embodiment.

[0012] Figure 5 is a flow chart of a method of operating a two-phase cooling system according to one embodiment. DETAILED DESCRIPTION

[0013] Various embodiments and aspects of the present invention will be described with reference to the details discussed below, and the accompanying drawings will illustrate various embodiments. The following description and accompanying drawings are explanations of the present invention and do not constitute limitations of the present invention. Many specific details are described to provide a thorough understanding of various embodiments of the present invention. However, in some cases, in order to provide a concise discussion of embodiments of the present invention, known or conventional details are not described.

[0014] Reference to "one embodiment" or "an embodiment" in the specification means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present invention. The phrase "in one embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment.

[0015] Embodiments of the present disclosure provide an advanced phase change cooling system with full redundancy. The phase change cooling system may include two condenser units operating in parallel. Each of the condenser units may be connected to a liquid supply line to provide cooling liquid to the electronic device, and may be connected to a vapor return line to return the vapor-phase evaporated coolant from the electronic device to the condenser unit. In some examples, two vapor return lines may be connected by a dedicated connecting line. Therefore, the vapor in the vapor return line may travel to an adjacent condenser unit. In one example, a pressure sensor may be connected to each vapor return line after the discharge side of the connection loop (e.g., between the condenser unit and the connection loop). In another example, a two-way pressure reducer may be included in the connecting line, and the pressure sensor may be connected to the connecting line on either side of the two-way pressure reducer. In some embodiments, a single main cooling supply may be provided to two condenser units, while in other embodiments, a dual (e.g., parallel) source may be provided to the condenser unit. The fluid provided by the cooling source may be controlled by a fluid pump on a single or dual main cooling source. A pressure sensor on the vapor return line can measure the vapor pressure in the vapor return line and control (eg, via a microcontroller) the fluid pump accordingly.

[0016] Therefore, embodiments of the present disclosure can achieve advanced thermal management for data centers and servers. Embodiments can adapt to different system-level and cluster-level architectures. Additional advantages of the present disclosure include high system reliability, increased power efficiency, and compatibility with different system and facility structures.

[0017] According to one embodiment, a liquid cooling device comprises: a first cooling circuit for providing cooling liquid to a heat load, wherein the first cooling circuit comprises a first condenser unit, a first liquid supply line, and a first vapor return line; and a second cooling circuit for providing cooling liquid to the heat load, wherein the second cooling circuit comprises a second condenser unit, a second liquid supply line, and a second vapor return line, wherein the first vapor return line and the second vapor return line are connected by an interconnection circuit. The liquid cooling device also comprises a first pressure sensor connected to the first vapor return line, a second pressure sensor connected to the second vapor return line, and at least one primary cooling source controlled based on the first pressure sensor and the second pressure sensor.

[0018] In one embodiment, at least one main cooling source includes a first main cooling source controlled by a first fluid control valve associated with the first condenser unit and a second main cooling source controlled by a second fluid control valve associated with the second condenser unit. In one embodiment, at least one main cooling source includes a first main cooling source controlled by a first fluid pump and a second main cooling source controlled by a second fluid pump. In one embodiment, a two-way fluid control valve couples the first main cooling source and the second main cooling source.

[0019] In one embodiment, the liquid cooling device further comprises a two-way fluid pressure reducer disposed on the interconnection loop. In one embodiment, the first pressure sensor and the second pressure sensor are disposed on the interconnection loop, and the two-way fluid pressure reducer is disposed between the first pressure sensor and the second pressure sensor on the interconnection loop. In one embodiment, the heat load comprises one or more electronic devices in the immersion cooling system. In one embodiment, the heat load comprises one or more servers of an electronic rack connected to one or more cooling devices of the first cooling loop or the second cooling loop. In one embodiment, the liquid cooling device further comprises a microcontroller to receive pressure data from the first pressure sensor and the second pressure sensor, and to control at least one main cooling source based on the pressure data. In some embodiments, the two-way pressure reducer and the first pressure sensor and the second pressure sensor are used to characterize and capture the heat load between the two condenser units in several cases. The heat load between the condenser units can be captured and characterized, and then used to control the delivery of cooling capacity to the condenser units and the distribution of coolant to the condenser units via at least one main cooling source by adjusting a fluid pump and / or a fluid valve associated with at least one main cooling source.

[0020] Figure 1A two-phase cooling system design 100 is shown according to one embodiment. The two-phase cooling system design 100 may include two redundant cooling circuits. The two-phase distribution unit may include two circuits, each of the two circuits including a primary cooling source, a condenser unit, a phase change circuit, and a pressure sensor. The load may be a two-phase based immersion cooling system, a thermosyphon based cooling system, or any other cooling system load.

[0021] A pressure sensor may be included in the distribution unit and may be used to sense the pressure of the vapor in the vapor return line. The pressure sensor may be located on the discharge side of the connection loop to measure the vapor pressure. The pressure sensor may be used to control the various valves of the main cooling source. In one example, the two-phase cooling system design 100 may include a single main cooling source and two separate valves for independently controlling the capacity of the condenser units.

[0022] In one embodiment, reference Figure 1 , the cooling system 100 includes a two-phase distribution unit 102. In one example, the two-phase distribution unit 102 includes two condenser units 104A and 104B, each of which is connected to a liquid supply line and a vapor return loop for providing liquid cooling to electronic equipment. For example, the condenser unit 104A can be connected to a liquid supply line 106A to provide cooling liquid to a phase change loop connected to a heat load (e.g., an immersion system or other phase change system of an electronic rack). The condenser unit 104A can also be connected to a vapor return line 108A for returning vapor (e.g., evaporated cooling liquid) from the phase change loop to the condenser unit 104A. Similarly, the condenser unit 104B can be connected to a liquid supply line 106B and a vapor return line 108B, each having functions similar to the liquid supply line 106A and the vapor return line 108A, respectively. As shown, condenser units 104A and 104B may both receive cooling liquid from a primary cooling source 120 (eg, via a primary cooling loop), which condenser units 104A and 104B may use to cool and condense vapor returned via vapor return lines 108A and 108B.

[0023] According to some embodiments, a first pressure sensor 125A can be coupled to the vapor return line 108A, and a second pressure sensor 125B can be coupled to the vapor return line 108B. In one example, the first pressure sensor 125A continuously or periodically measures the vapor pressure in the vapor return line 108A. Similarly, the second pressure sensor 125B continuously or periodically measures the vapor pressure in the vapor return line 108B.

[0024] In one example, the steam return lines 108A and 108B can be connected via an interconnection loop 115. The interconnection loop 115 allows steam to travel between the steam return lines 108A and 108B. Therefore, if the two condenser units 104A and 104B are operated simultaneously, the heat load can be almost evenly distributed between the two condenser units 104A and 104B. Alternatively, if one of the condenser units 104A or 104B is not operated (e.g., has failed), the steam can travel between the steam return lines 108A and 108B so that the condenser unit 104A or 104B in operation can handle the entire heat load. In addition, in such an embodiment, the pressures measured by the pressure sensors 125A and 125B can be the same or similar, because the steam is allowed to travel freely between the steam return lines 108A and 108B. In one example, the pressure measured by pressure sensor 125B can control fluid control valve 112A, and thereby control the cooling capacity of condenser unit 104A. Similarly, the pressure measured by pressure sensor 125A can control fluid control valve 112B, and thereby control the cooling capacity of condenser unit 104B. In one example, a heat load (e.g., electronic equipment) can be included in a phase change loop 118, which can be an electronic rack, an immersion cooling system, or other phase change cooling loop. Phase change loop 118 can be understood as a cooling loop within an information technology (IT) system, and because the fluid undergoes a phase change within the cooling loop within the IT system, it can be understood as a phase change line or phase change loop.

[0025] Figure 2 A cooling system design 200 according to some embodiments is shown. The interconnection loop can connect the vapor return lines of the parallel cooling loops. Pressure sensors can be provided on the interconnection loops. In addition, a bidirectional fluid pressure reducer can be included on the interconnection loops between the pressure sensors.

[0026] In one embodiment, reference Figure 2 , the cooling system 200 may include a two-phase distribution unit 202, which may be the same as or similar to the two-phase distribution unit 102. The two-phase distribution unit 202 may include two condenser units 204A and 204B, which may be the same as or similar to the condenser units 104A and 104B. Figure 1In the system 100, the cooling system 200 includes liquid supply lines 206A and 206B for each condenser unit and vapor return lines 208A and 208B to provide cooling liquid to a heat load such as a server or a server cluster and to receive vapor from a heat load such as a server or a server cluster. The heat load may be included in a phase change loop 218, which may be an electronic rack, an immersion cooling system, or other phase change cooling loops. In one example, an interconnection loop 215 may connect vapor return lines 208A and 208B. Pressure sensors 225A and 225B may be coupled to the interconnection loop 215 on each side of a two-way pressure reducer 228. The two-way pressure reducer 228 may generate a pressure difference in either direction between the vapor return lines 208A and 208B. Therefore, the pressure measured by the pressure sensor 225A may be different from the pressure measured by the pressure sensor 225B. The measured pressure difference may indicate the vapor flow through the two-way pressure reducer, or may indicate the difference in the vapor load between the two lines. Thus, the measured vapor pressure and vapor flow may provide accurate heat load conditions that may be used to adjust the cooling capacity of the primary cooling sources 220A and 220B and the condenser units 204A and 204B.

[0027] and Figure 1 Similarly, pressure sensors 225A and 225B can be used to control the main cooling source 220A to condenser unit 204A and the main cooling source 220B to condenser unit 204B via fluid control valves, main fluid pump 212 and backup pump 214. Pressure sensors 225A and 225B can work as redundant units for pressure measurement. In one example, a two-way valve can connect the inputs of main cooling sources 220A and 220B so that main fluid pump 212 or backup pump 214 can provide cooling fluid to any condenser unit 204A and 204B according to the operating state of each of condenser units 204A and 204B, main cooling sources 220A and 220B, etc. In addition, the pressure measurement of pressure sensors 225A and 225B can provide information about the operating state of condenser units 204A and 204B and the heat load returned by each vapor return line 208A and 208B. Then, the two-way valve and the main fluid pump 212 and the backup pump 214 can be controlled according to the specific situation. For example, if the main fluid pump 212 fails, the backup pump 214 can provide cooling fluid to the condenser unit 204A via the two-way valve. In another example, if the pressure sensors 225A and 225B indicate that either of the condenser units 204A and 204B has failed, the main fluid pump 212 and the backup pump 214 and the two-way valve can be controlled to provide cooling liquid, and thus the cooling capacity is delivered to the operating condenser unit 204A or 204B.

[0028] Figure 3Another redundant two-phase cooling design is shown, where the two-phase distribution unit includes a parallel main cooling source input with a fluid pump. The cooling design can be used in conjunction with an immersion system, which means that the vapor generated within the immersion system or cluster can be greatly varied and distributed to the two vapor return lines in different ways. Depending on the heat load provided to each condenser unit of the cooling system, this embodiment can provide efficient management of the parallel cooling system.

[0029] In one embodiment, reference Figure 3 , the cooling system 300 may include a two-phase distribution unit 302, which may be similar to the two-phase distribution units 102 and 202. Figure 1 Similar to system 100, system 300 includes two condenser units 304A and 304B and liquid supply lines 306A and 306B and vapor return lines 308A and 308B for each condenser unit 304A and 304B to provide cooling liquid to and receive vapor from immersion system 310. Immersion system 310 can be a tank filled with cooling liquid (e.g., filled via liquid supply lines 306A and 306B) in which one or more servers or other electronic devices are immersed for cooling. Heat generated during operation of the servers can be extracted by evaporation of the cooling liquid. The evaporated cooling liquid (also referred to as vapor) can then be returned to condenser units 304A and 304B via vapor return lines 308A and 308B.

[0030] In some embodiments, system 300 also includes a fluid control valve associated with each condenser unit 304A and 304B. System 300 may also include a pressure sensor 325A on the vapor return line 308A and a pressure sensor 325B on the vapor return line 308B. As shown, pressure sensor 325A can be communicated with the fluid control valve and control the fluid control valve, and pressure sensor 325B can be communicated with the fluid control valve and control the fluid control valve. In one example, vapor return line 308A and 308B can be connected via interconnection loop 315.

[0031] Similar to Figure 2 , pressure sensors 325A and 325B may be used to control the primary cooling source 320A to condenser unit 304A and the primary cooling source 320B to condenser unit 304B via fluid control valves, primary fluid pumps 314A and 314B. Pressure sensors 325A and 325B may work as redundant units for pressure measurement.

[0032] Figure 4Another redundant two-phase cooling design is shown, where the two-phase distribution unit includes a parallel main cooling source input with a fluid pump. The cooling design can be used in conjunction with an immersion system, which means that the vapor generated within the immersion system or cluster can be greatly varied and distributed to the two vapor return lines in different ways. Depending on the heat load provided to each condenser unit of the cooling system, this embodiment can provide efficient management of the parallel cooling system.

[0033] In one embodiment, reference Figure 4 , the cooling system 400 may include a two-phase distribution unit 402, which may be similar to the two-phase distribution units 102, 202, and 302. Figure 3 Similar to the system 300 of , the system 400 includes two condenser units 404A and 404B, liquid supply lines 406A and 406B for each condenser unit 404A and 404B and vapor return lines 408A and 408B to provide cooling liquid to a server rack 435 of a plurality of servers 430A to 430D, and to receive vapor from a server rack 435 of a plurality of servers 430A to 430D, and main cooling sources 420A and 420B, which have fluid pumps 412A and 412B to provide cooling fluid to the condenser units 404A and 404B. The system 400 may also include a pressure sensor 425A on the vapor return line 408A and a pressure sensor 425B on the vapor return line 408B. As shown, the pressure sensors 425A and 425B may be encapsulated in the two-phase distribution unit 402. Additionally, interconnect loop 415 may couple vapor return lines 408A and 408B. A two-way fluid valve may also be provided between primary cooling sources 420A and 420B, which may be used to direct cooling fluid from one primary cooling source (e.g., 420A) to an opposing condenser unit (e.g., condenser unit 404B).

[0034] Figure 5A flow chart of a method 500 for operating a parallel cooling loop based on a vapor return line pressure is shown. At box 510, the vapor pressure in the first vapor return line is measured via a first pressure sensor, and the vapor pressure in the second vapor return line is measured via a second pressure sensor. At box 520, the heat load extracted from the first vapor return line and the second vapor return line is determined based on the vapor pressure measured by the first pressure sensor and the second pressure sensor. At box 530, processing logic (e.g., a microcontroller) controls the cooling capacity to the first condenser unit based on the vapor pressure and heat load of the first vapor return line. At box 540, processing logic controls the cooling capacity to the second condenser unit based on the vapor pressure and heat load of the second vapor return line. Box 540 and box 530 can be performed simultaneously and in parallel to dynamically control the cooling capacity of the two condenser units based on the pressure data measured by the first pressure sensor and the second pressure sensor. Optionally, at box 540, processing logic can identify abnormal operation of the first cooling loop or the second cooling loop based on the vapor pressure measured by the first pressure sensor and the second pressure sensor.

[0035] In the foregoing description, embodiments of the present invention have been described with reference to specific exemplary embodiments of the present invention. It is apparent that various modifications may be made thereto without departing from the broader spirit and scope of the present invention as set forth in the appended claims. Therefore, the description and drawings are to be regarded as illustrative rather than restrictive.

Claims

1. A cooling device, comprising: a first cooling circuit to provide cooling liquid to the heat load, wherein the first cooling circuit comprises a first condenser unit, a first liquid supply line, and a first vapor return line; a second cooling circuit to provide cooling liquid to the heat load, wherein the second cooling circuit comprises a second condenser unit, a second liquid supply line, and a second vapor return line; an interconnection circuit coupling the first vapor return line and the second vapor return line; a two-way fluid pressure reducer, arranged on the interconnection circuit; a first pressure sensor coupled to the first vapor return line; a second pressure sensor coupled to the second vapor return line; and At least one primary cooling source is controlled based on the first pressure sensor and the second pressure sensor.

2. The cooling device according to claim 1, wherein: The at least one primary cooling source includes a first primary cooling source controlled by a first fluid control valve associated with the first condenser unit and a second primary cooling source controlled by a second fluid control valve associated with the second condenser unit.

3. The cooling device according to claim 1, wherein: The at least one primary cooling source includes a first primary cooling source controlled by a first fluid pump and a second primary cooling source controlled by a second fluid pump.

4. The cooling device according to claim 3, wherein: A two-way fluid control valve couples the first primary cooling source and the second primary cooling source.

5. The cooling device according to claim 1, wherein: The first pressure sensor and the second pressure sensor are disposed on the interconnection circuit, and the bidirectional fluid pressure reducer is disposed between the first pressure sensor and the second pressure sensor on the interconnection circuit.

6. The cooling device according to claim 1, wherein: The heat load includes one or more electronic devices in an immersion cooling system.

7. The cooling device according to claim 1, wherein: The heat load includes one or more servers of an electronics rack coupled to one or more cooling devices of the first cooling loop or the second cooling loop.

8. The cooling device of claim 1, further comprising a microcontroller for receiving pressure data from the first pressure sensor and the second pressure sensor and controlling the at least one primary cooling source based on the pressure data.

9. A cooling system comprising: a first cooling circuit to provide cooling liquid to the immersion tank, wherein the first cooling circuit comprises a first condenser unit, a first liquid supply line, and a first vapor return line; a second cooling circuit to provide cooling liquid to the immersion tank, wherein the second cooling circuit comprises a second condenser unit, a second liquid supply line, and a second vapor return line; an interconnection circuit coupling the first vapor return line and the second vapor return line; a two-way fluid pressure reducer, arranged on the interconnection circuit; a first pressure sensor coupled to the first vapor return line; a second pressure sensor coupled to the second vapor return line; and At least one primary cooling source includes a fluid control valve controlled based on the first pressure sensor and the second pressure sensor.

10. The cooling system of claim 9, wherein: The at least one primary cooling source includes a first primary cooling source controlled by a first fluid control valve associated with the first condenser unit and a second primary cooling source controlled by a second fluid control valve associated with the second condenser unit.

11. The cooling system of claim 9, wherein: The at least one primary cooling source includes a first primary cooling source controlled by a first fluid pump and a second primary cooling source controlled by a second fluid pump.

12. The cooling system of claim 11, wherein: A two-way fluid control valve couples the first primary cooling source and the second primary cooling source.

13. The cooling system of claim 9, wherein: The first pressure sensor and the second pressure sensor are disposed on the interconnection circuit, and the bidirectional fluid pressure reducer is disposed between the first pressure sensor and the second pressure sensor on the interconnection circuit.

14. The cooling system of claim 9, wherein: The immersion tank includes one or more electronic devices in an immersion cooling system.

15. The cooling system of claim 9, wherein: The immersion tank includes one or more servers of an electronics rack coupled to one or more cooling devices of the first cooling loop or the second cooling loop.

16. A method of controlling a two-phase cooling distribution unit, comprising: receiving pressure data from a first pressure sensor coupled to a first vapor return line of a first coolant distribution circuit; receiving pressure data from a second pressure sensor coupled to a second vapor return line of a second coolant distribution circuit, wherein the second coolant distribution circuit operates in parallel with the first coolant distribution circuit; controlling a cooling capacity of the first coolant distribution circuit based on the pressure data from the second pressure sensor; and controlling a cooling capacity of the second coolant distribution circuit based on the pressure data from the first pressure sensor, The first steam return pipeline and the second steam return pipeline are connected via an interconnection loop, and a two-way fluid pressure reducer is provided on the interconnection loop.

17. The method of claim 16, further comprising: Based on the vapor pressures measured by the first pressure sensor and the second pressure sensor, a heat load extracted from the first vapor return line and the second vapor return line is determined.

18. The method of claim 16, further comprising: Based on the vapor pressure measured by the first pressure sensor and the second pressure sensor, abnormal operation of the first coolant distribution circuit or the second coolant distribution circuit is identified.

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