Liquid cooling unit performance test system

Abstract

The present application relates to liquid cooling heat dissipation device performance detection technical field, specifically relates to a kind of liquid cooling unit performance test system.Liquid cooling unit has FWS side and TCS side, system includes: cold, heat source regulating station;First heat exchanger, two sides are connected FWS side, cold source regulating station by first circulation loop, second circulation loop respectively;Fourth heat exchanger, two sides are connected TCS side, heat source regulating station by seventh circulation loop, ninth circulation loop respectively;Second heat exchanger, two sides are connected cold source regulating station, seventh circulation loop by third circulation loop, twelfth circulation loop respectively;Third heat exchanger, two sides are connected cold source regulating station, heat source regulating station by fourth circulation loop, eighth circulation loop respectively;Refrigerating machine, its evaporation side, condensing side are connected cold, heat source regulating station by fifth circulation loop, eleventh circulation loop respectively.The present application can realize high-power load bearing, low energy consumption operation, wide temperature range cold source accurate control, multi-medium circulation combination and full working condition accurate simulation.

Description

Technical Field

[0001] This invention relates to the field of performance testing technology for liquid cooling heat dissipation equipment, and specifically to a liquid cooling unit performance testing system. Background Technology

[0002] With the rapid development of high-density computing power, large-scale industrial temperature control, new energy storage, and power battery systems, equipment power density continues to rise, and liquid cooling is gradually becoming the mainstream solution for high power density scenarios. The liquid cooling unit (CDU), as the core hub of the liquid cooling system, undertakes functions such as coolant circulation, pressure regulation, flow distribution, heat exchange and cooling, and pressure stabilization and liquid replenishment. Its heat exchange performance, circulation stability, multi-condition adaptability, multi-media compatibility, and wide-temperature-range operational reliability directly affect system efficiency and reliability. Therefore, full-performance testing and calibration are required before shipment.

[0003] Existing CDU testing systems typically use electrically heated dummy loads to simulate the thermal load on the TCS side (load side). Heat is transferred from the CDU to the FWS side (cold source side), and then dissipated by an open cooling tower. This approach has the following drawbacks: First, the electric heating power is limited, usually only suitable for small and medium-sized CDUs below 500kW, making it difficult to meet the full-load, overload, and variable-load testing requirements of megawatt-level large CDUs; second, electrical energy is directly converted into heat energy without energy recovery, resulting in high testing energy consumption and operating costs; third, cooling tower heat dissipation depends on ambient temperature and humidity, and the cold source temperature adjustment range is narrow and has low precision, making it impossible to simulate wide-temperature-range operating conditions; fourth, it only adapts to a single coolant medium, making it difficult to achieve independent circulation, switching, and combination of multiple media on the FWS and TCS sides; fifth, it lacks the ability to simulate dynamic variable load, variable flow, and variable temperature operating conditions, resulting in limited testing accuracy and comprehensiveness.

[0004] Therefore, existing testing systems are insufficient to meet the requirements of large-scale, multi-media compatible, wide-temperature-range, and low-energy-consumption CDU R&D, quality control, and performance calibration. It is urgent to solve the problems existing in current liquid-cooled unit testing systems. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a liquid cooling unit performance testing system that can achieve high power load bearing, low energy consumption operation, wide temperature range cold source precise control, multi-media independent circulation combination, and full-condition accurate simulation.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is: a liquid cooling unit performance testing system, wherein the liquid cooling unit has an FWS side and a TCS side, and the testing system includes: Cold source regulating station, heat source regulating station; The first heat exchanger is connected to the FWS side on one side through a first circulation loop and to the cold source regulating station on the other side through a second circulation loop, so as to realize heat exchange between the FWS side and the cold source regulating station. The fourth heat exchanger is connected to the TCS side on one side through the seventh circulation loop and to the heat source regulating station on the other side through the ninth circulation loop, which is used to realize heat exchange between the TCS side and the heat source regulating station. The second heat exchanger is connected to the cold source regulating station on one side through the third circulation loop, and to the fourth heat exchanger side of the seventh circulation loop on the other side through the twelfth circulation loop, which is used to realize heat exchange between the cold source regulating station and the TCS side. The third heat exchanger is connected to the cold source regulating station on one side through the fourth circulation loop and to the heat source regulating station on the other side through the eighth circulation loop, which is used to realize heat exchange between the cold source regulating station and the heat source regulating station. The refrigeration unit has its evaporator side connected to the cold source regulating station via the fifth circulation loop to regulate the temperature of the medium within the cold source regulating station, and its condenser side connected to the heat source regulating station via the eleventh circulation loop to regulate the temperature of the medium within the heat source regulating station.

[0007] Furthermore, the liquid cooling unit performance testing system also includes: The first injection tank is connected to the first circulation loop and is used to inject circulating medium into the first circulation loop; The second injection tank is connected to the seventh circulation loop and is used to inject circulating medium into the seventh circulation loop.

[0008] Furthermore, the circulating medium in the first injection tank and the second injection tank is one of water, ethylene glycol aqueous solution, and propylene glycol aqueous solution, respectively.

[0009] Furthermore, the liquid cooling unit performance testing system also includes: The first closed-type airbag expansion tank is connected to the first circulation loop and is used to maintain pressure and compensate for or absorb volume changes caused by thermal expansion and contraction of the first circulation loop. The second closed-loop airbag expansion tank is connected to the seventh circulation loop and is used to maintain pressure and compensate for or absorb volume changes caused by thermal expansion and contraction of the seventh circulation loop.

[0010] Furthermore, the liquid cooling unit performance testing system also includes a fifth heat exchanger and a cooling tower. One side of the fifth heat exchanger is connected to the heat source regulating station through the tenth circulation loop, and the other side is connected to the cooling tower through the sixth circulation loop, which is used to realize the waste heat discharge of the heat source regulating station.

[0011] Furthermore, pumps are installed in all eleventh circulation loops.

[0012] Furthermore, the pumps in the fifth, sixth, and eleventh circulation loops are fixed-frequency pumps; The pumps in the first, second, third, fourth, seventh, eighth, ninth, and tenth circulation loops are variable frequency pumps.

[0013] Furthermore, the seventh circulation loop also has a bypass line connected in parallel with its pump; among which, When using the second heat exchanger to achieve heat exchange between the cold source regulating station and the TCS side, the pump in the seventh circulation loop does not work, the bypass pipeline is open, and the return flow is controlled by the built-in pump of the liquid cooling unit. When the heat source regulating station and the TCS side are exchanged using the fourth heat exchanger, the pump in the seventh circulation loop is working, and the bypass pipeline is not connected.

[0014] Furthermore, temperature sensors and differential pressure sensors are installed at the inlet and outlet positions of the connecting pipe section between the first circulation loop and the FWS side; Temperature sensors and differential pressure sensors are installed at the inlet and outlet positions of the connecting pipe section between the seventh circulation loop and the TCS side.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects: 1. It has a strong high-power load capacity and is suitable for full-condition testing of large CDUs.

[0016] By forming a closed-loop heat exchange circuit with the fourth heat exchanger and the heat source regulation station, a high-power heat load simulation is performed on the TCS side, replacing the traditional electric heating dummy load. This breaks through the power limit of the electric heating element and can stably adapt to the full load, extreme load and dynamic variable load tests of megawatt-level large CDUs, solving the problem that the traditional electric heating dummy load has insufficient power and cannot adapt to large CDU tests.

[0017] 2. The energy consumption of the test is greatly reduced, and the energy is recovered and recycled.

[0018] The heat exchange between the cold source regulation station and the heat source regulation station is achieved through the third heat exchanger, and the heat source regulation station is connected through the eleventh circulation loop via the condenser side of the chiller, realizing bidirectional heat exchange and waste heat recovery between the cold and heat sources. This replaces the traditional direct power consumption and discharge mode, reduces the energy consumption and operating cost of the entire testing process, and solves the problems of extremely high testing energy consumption and serious resource waste.

[0019] 3. The cold source temperature has a wide range of adjustment and is not limited by climate conditions.

[0020] The evaporator side of the chiller is connected to the cold source regulating station through the fifth circulation loop, which can actively regulate the temperature of the medium in the cold source regulating station. This replaces the passive heat dissipation method of the traditional open cooling tower, gets rid of the limitations of climatic conditions such as ambient temperature, humidity, and wind speed, and realizes accurate simulation of cold source working conditions in a wide temperature range from low temperature to high temperature. This solves the problems of limited temperature range and heat dissipation failure in summer of the cooling tower in the background technology.

[0021] 4. Flexible adaptation to multiple media, comprehensive testing scenarios: The first heat exchanger separates the FWS side from the cold source conditioning station for heat exchange, and the fourth heat exchanger separates the TCS side from the heat source conditioning station for heat exchange, so that the FWS side and the TCS side form independent circulation loops that do not interfere with each other, and can be filled with different media such as water, ethylene glycol solution, propylene glycol solution, and special heat-conducting liquid, to flexibly simulate various medium combinations such as water / ethylene glycol solution, ethylene glycol solution / ethylene glycol solution, ethylene glycol solution / propylene glycol solution, and special heat-conducting liquid / water, to solve the problem of single test scene and the inability to flexibly adapt to multiple media in the background technology, to realize full-scene multi-medium compatible testing, and to comprehensively verify the operation performance, heat exchange efficiency, and sealing compatibility of the CDU under different medium combinations. The test results are highly matched with the actual engineering working conditions.

[0022] 5. High working condition simulation accuracy and strong testing comprehensiveness: The first heat exchanger, the second heat exchanger, the third heat exchanger, and the fourth heat exchanger cooperatively constitute a multi-path closed-loop heat exchange network with the cold source conditioning station, the heat source conditioning station, and the refrigerator, so as to respectively control the temperature, flow rate, and pressure of the FWS side, the TCS side, the cold source side, and the heat source side, to accurately simulate complex dynamic working conditions such as variable load, variable flow rate, variable temperature, and variable medium type, and to solve the problems of poor working condition simulation flexibility, insufficient testing accuracy, and insufficient comprehensiveness in the background technology. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 A system flow diagram of the liquid cooling unit performance testing system of the present application; Figure 2 A corresponding relationship diagram of each loop of the liquid cooling unit performance testing system of the present application; Figure 3 A group control logic flow diagram of the liquid cooling unit performance testing system of the present application. DETAILED DESCRIPTION

[0024] In order to make the content of the present application easier to be clearly understood, the present application will be further described in detail below according to specific embodiments and in conjunction with the accompanying drawings.

[0025] As shown in Figure 1 A liquid cooling unit performance testing system, the liquid cooling unit has an FWS side and a TCS side, and the testing system comprises: a cold source conditioning station and a heat source conditioning station; a first heat exchanger, one side of which is connected to the FWS side through a first circulation loop, and the other side of which is connected to the cold source conditioning station through a second circulation loop, for realizing heat exchange between the FWS side and the cold source conditioning station; a fourth heat exchanger, one side of which is connected to the TCS side through a seventh circulation loop, and the other side of which is connected to the heat source conditioning station through a ninth circulation loop, for realizing heat exchange between the TCS side and the heat source conditioning station; a second heat exchanger, one side of which is connected to the cold source conditioning station through a third circulation loop, and the other side of which is connected to the fourth heat exchanger side of the seventh circulation loop through a twelfth circulation loop, for realizing heat exchange between the cold source conditioning station and the TCS side; a third heat exchanger, one side of which is connected to the cold source conditioning station through a fourth circulation loop, and the other side of which is connected to the heat source conditioning station through an eighth circulation loop, for realizing heat exchange between the cold source conditioning station and the heat source conditioning station; a refrigerating machine, the evaporation side of which is connected to the cold source conditioning station through a fifth circulation loop, for regulating the temperature of the medium in the cold source conditioning station, and the condensation side of which is connected to the heat source conditioning station through an eleventh circulation loop, for regulating the temperature of the medium in the heat source conditioning station.

[0026] Preferably, as shown in Figure 1 the liquid cooling unit performance test system further comprises: a first liquid injection tank connected to the first circulation loop, for injecting circulating medium into the first circulation loop; a second liquid injection tank connected to the seventh circulation loop, for injecting circulating medium into the seventh circulation loop.

[0027] Preferably, as shown in Figure 1 the liquid cooling unit performance test system further comprises: a first closed gas bag type expansion tank connected to the first circulation loop, for constant pressure, compensation or absorption of volume change caused by thermal expansion and contraction of the first circulation loop; a second closed gas bag type expansion tank connected to the seventh circulation loop, for constant pressure, compensation or absorption of volume change caused by thermal expansion and contraction of the seventh circulation loop.

[0028] Preferably, as shown in Figure 1 the liquid cooling unit performance test system further comprises a fifth heat exchanger and a cooling tower, one side of the fifth heat exchanger being connected to the heat source conditioning station through a tenth circulation loop, and the other side of the fifth heat exchanger being connected to the cooling tower through a sixth circulation loop, for realizing waste heat discharge of the heat source conditioning station.

[0029] Preferably, pumps are arranged in the first circulation loop to the eleventh circulation loop. More preferably, the pumps of the fifth circulation loop, the sixth circulation loop and the eleventh circulation loop are constant frequency pumps; The pumps of the first circulation loop, the second circulation loop, the third circulation loop, the fourth circulation loop, the seventh circulation loop, the eighth circulation loop, the ninth circulation loop and the tenth circulation loop are variable frequency pumps.

[0030] wherein the seventh circulation loop further has a bypass pipeline in parallel with the pump thereof; wherein, when the second heat exchanger is used to realize heat exchange between the cold source conditioning station and the TCS side, the pump of the seventh circulation loop does not work, and the bypass pipeline is turned on, and the backflow flow is controlled through the built-in pump of the liquid cooling unit; When the heat source regulating station and the TCS side are exchanged using the fourth heat exchanger, the pump in the seventh circulation loop is working, and the bypass pipeline is not connected.

[0031] All heat exchangers may, but are not limited to, plate heat exchangers.

[0032] The above-mentioned solutions will be described in detail below.

[0033] Functions of each loop.

[0034] 1. First Loop (FWS Loop) This circuit is used to provide a matching flow rate (the frequency of the pump PUMP1 in this circuit is adjusted according to the flow meter F1) and inlet temperature based on the operating requirements of the primary side (FWS side, cold source side) of the CDU (liquid cooling unit). Inlet and outlet temperature sensors and differential pressure sensors are configured at the inlet and outlet positions of the connecting pipe section between the circuit and the primary side (FWS side, cold source side) of the CDU, which can monitor and collect the inlet and outlet temperature and differential pressure parameters of the circuit entering the primary side (FWS side, cold source side) of the CDU in real time.

[0035] 2. Second circulation loop (circulation loop from cold source regulating station to first heat exchanger) This circuit is used to transport the cold source medium from the cold source conditioning station to the first plate heat exchanger, and regulate the inlet temperature of the medium on the primary side (FWS side, cold source side) of the CDU through heat exchange (by adjusting the frequency of the pump PUMP2 in this circuit).

[0036] 3. Third circulation loop (circulation loop from cold source regulating station to second plate heat exchanger) This loop is used to transport the cold source medium from the cold source regulating station to the second plate heat exchanger, and regulate the inlet temperature of the medium in the built-in TCS circulation loop on the secondary side (load side) of the CDU through heat exchange (the frequency of pump PUMP5 in this loop). When using the built-in TCS circulation, pump PUMP9 in the seventh circulation loop is closed, and the water pump built into the CDU is used. Bypass is achieved by closing CV2 and opening CV3.

[0037] 4. Fourth circulation loop (circulation loop from cold source regulating station to third plate heat exchanger) This loop forms a circulation path between the cold source regulating station and the third plate heat exchanger, used to transport the cold source medium in the cold source regulating station to the third plate heat exchanger and participate in heat exchange, so as to realize heat exchange on the side of the cold source regulating station (by adjusting the frequency of the pump PUMP4 in this loop).

[0038] 5. Fifth circulation loop (circulation loop from cold source regulating station to evaporator side of refrigeration unit) This circuit continuously provides cooling capacity to the cold source regulating station through the cooling effect of the evaporator side of the chiller, and can regulate the temperature of the medium in the cold source regulating station to a minimum of 3°C.

[0039] 6. Sixth circulation loop (circulation loop from cooling tower to fifth plate heat exchanger) This circuit serves as an auxiliary heat dissipation circuit, receiving the heat transferred from the fifth plate heat exchanger and delivering it to the cooling tower (which can be closed or open, with a variable frequency cooling tower fan). The system's waste heat is then discharged to the external environment through an outdoor natural cold source.

[0040] 7. Seventh Loop (TCS Side Loop) This circuit is used to provide a matching flow rate (adjusting the frequency of the pump PUMP9 in this circuit) and inlet temperature according to the operating requirements of the CDU secondary side (TCS side, load side). Inlet and outlet temperature sensors and differential pressure sensors are installed at the inlet and outlet positions of the connecting pipe section between the circuit and the CDU secondary side (TCS side, load side) to monitor and collect the inlet and outlet temperature and differential pressure parameters of the circuit entering the CDU secondary side (TCS side, load side) in real time.

[0041] 8. Eighth circulation loop (circulation loop from heat source regulating station to third plate heat exchanger) This loop forms a circulation path between the heat source regulating station and the third plate heat exchanger, used to transport the heat source medium in the heat source regulating station to the third plate heat exchanger and participate in heat exchange, thereby realizing heat exchange on the heat source regulating station side.

[0042] 9. Ninth Circulation Loop (Circulation Loop from Heat Source Regulating Station to Fourth Plate Heat Exchanger) This circuit is used to transport the heat source medium in the heat source regulating station to the fourth plate heat exchanger, and regulate the inlet temperature of the medium on the TCS side through heat exchange (by adjusting the frequency of the pump PUMP8 in this circuit).

[0043] 10. Tenth Circulation Loop (Circulation Loop from Heat Source Regulating Station to Fifth Plate Heat Exchanger) This loop is used to transfer excess heat from the heat source regulating station to the fifth plate heat exchanger, and then exchange heat with the sixth circulation loop through the fifth plate heat exchanger to achieve the discharge of waste heat from the heat source regulating station side (cooling tower fan frequency converter, PUMP10 pump frequency converter of this loop, joint control. The pump frequency is adjusted first, for example, when the load is low, the heat exchange is small. When the pump frequency converter is reduced to the minimum limit and still cannot meet the requirements, the cooling tower fan frequency can be adjusted).

[0044] 11. Eleventh Circulation Loop (Circulation Loop from Heat Source Regulating Station to Refrigeration Unit Condenser Side) This circuit continuously provides heat to the heat source regulating station through the heat dissipation effect of the condenser side of the refrigeration unit, and can regulate the temperature of the medium in the heat source regulating station to a maximum of 60℃.

[0045] 12. Twelfth Circulation Loop (TCS side to second plate heat exchanger circulation loop) This loop simulates the operation of the CDU's built-in TCS loop by disabling pump PMUP9 and opening the bypass lines (CV2, CV4, and CV6 are closed; CV3 and CV5 are open). The loop flow is controlled by the CDU's built-in pump, and the medium temperature is regulated by the heat exchange of the third loop (the loop from the cold source regulating station to the second plate heat exchanger) (by adjusting the frequency of pump PUMP5 in the third loop).

[0046] (II) Functions of each storage tank 1. Cold source conditioning station (can be, but is not limited to, a 20 wt% ethylene glycol solution) As a regulating station for the cold source system, it provides a constant-temperature cold source medium to the relevant loops of the system, ensuring the stability of the liquid supply temperature of the corresponding loops. The cold source regulating station is connected to the second, third, fourth, and fifth circulation loops to jointly complete the temperature regulation of the cold source regulating station's water tank (the temperature of the cold source regulating station's water tank is controlled by adjusting the frequency of the pump PUMP4 in the fourth circulation loop). 2. Heat source regulating station As a regulating station for the heat source system, it provides a constant-temperature heat source medium to each loop of the system, ensuring the stability of the liquid supply temperature in the corresponding loop. The heat source regulating station is connected to the eighth, ninth, tenth, and eleventh circulation loops to jointly complete the temperature regulation of the water tank in the heat source regulating station (the temperature of the water tank in the heat source regulating station is controlled by adjusting the frequency of pump PUMP10 in the tenth circulation loop). 3. First injection tank The first injection tank is used to inject circulating media into the primary side of the CDU (FWS side circulation loop, i.e., the first circulation loop) before system testing, supporting multi-type media adaptation and switching.

[0047] 4. Second injection tank The second injection tank is used to inject circulating media into the secondary side of the CDU (TCS side circulation loop, i.e. the seventh circulation loop) before system testing, supporting multi-type media adaptation and switching.

[0048] The compatible media combinations for the first and second injection tanks include water / ethylene glycol aqueous solution, ethylene glycol aqueous solution / ethylene glycol aqueous solution, ethylene glycol aqueous solution / propylene glycol aqueous solution, and special heat transfer fluid / water, which can be flexibly selected according to the actual application scenario. After the current media pair test is completed, if it is necessary to change to another media pair for testing, the residual media in the original circulation loop must be drained first.

[0049] 5. First closed-type airbag expansion tank The tank contains a rubber air bladder, which is filled with nitrogen on the outside and connected to the inlet of pump PUMP1 on the primary side of the CDU (FWS circulation loop) on the inside. It is mainly used to maintain pressure, compensate for or absorb volume changes caused by thermal expansion and contraction of the first circulation loop, prevent air intake into the system and water pump cavitation, and maintain stable pipeline pressure.

[0050] 6. Second closed-type airbag expansion tank The tank contains a rubber air bladder, which is filled with nitrogen on the outside and connected to the inlet of pump PUMP9 on the secondary side of the CDU (TCS circulation loop) on the inside. It is mainly used for pressure stabilization, compensating for or absorbing volume changes caused by thermal expansion and contraction of the seventh circulation loop, preventing air intake into the system and water pump cavitation, and maintaining stable pipeline pressure.

[0051] (III) Functions of each regulating valve Valve CV1, configured in the seventh circulation loop, is an electric or pneumatic actuator-operated, adjustable electric or pneumatic two-way shut-off valve used to simulate the pressure loss of the TCS load-side pipeline (different pipeline resistance characteristics are achieved by adjusting the opening of CV1). It can be used when the CDU built-in circulation is used in circulation loop 7 (when pump PUMP9 stops running, CV2 is closed, and CV3 is open). If pump PUMP9 is used in the seventh circulation loop, the CV1 regulating valve can be fully opened.

[0052] Valves CV2-CV6 are on / off type electric or pneumatic butterfly valves controlled by electric or pneumatic actuators. Valve CV2 is connected in series with pump PUMP9 and then in parallel with the bypass line. Valve CV3 is located on the bypass line; the bypass line can only be used when valve CV3 is open. Valves CV4-CV6 are used to control the on / off connection between the seventh and twelfth circulation loops, as well as between the seventh circulation loop and the fourth plate heat exchanger. When valves CV4 and CV6 are open and valve CV5 is closed, the seventh circulation loop is connected to the twelfth circulation loop. Conversely, when valves CV4 and CV6 are closed and valve CV5 is open, the seventh circulation loop is connected to the twelfth circulation loop.

[0053] (iv) Working methods With the inlet temperature and flow rate of the CDU primary-side FWS loop and the CDU secondary-side TCS loop as the core control targets, and equipped with a cold source control station, a heat source control station, and multiple sets of circulation loops, the system achieves precise and stable operation under test conditions through hierarchical closed-loop control, variable frequency speed regulation, and unit linkage control. The collaborative working mode of each component and loop in the system is as follows: 1. System Hardware Foundation and Control Prerequisites This system includes a cold source regulating station, a heat source regulating station, a first liquid injection tank, a second liquid injection tank, four liquid storage tanks, multiple plate heat exchangers (from the first to the fifth plate heat exchanger), a chiller, a cooling tower, and 12 circulation loops. The pumps in the fifth, eleventh, and sixth circulation loops are fixed-frequency pumps, while the pumps in the remaining circulation loops are variable-frequency pumps. The flow rate of the loops can be closed-loop controlled by adjusting the speed of the variable-frequency pumps. The fixed-frequency pump loops regulate the heating and cooling capacity based on the loading and unloading actions of the chiller. All temperature and differential pressure signals are collected in real time by corresponding sensors and uploaded to the group control master station for unified calculation and command issuance, constructing a fully integrated closed-loop control system.

[0054] 2. Core regulatory objectives and overall control logic This system sets dual core control targets: the inlet temperature and flow rate of the CDU primary-side FWS loop, and the inlet temperature and flow rate of the CDU secondary-side TCS loop. All loop control actions revolve around these core targets. The control logic follows the principle of "constant temperature protection for cold and heat sources, precise control of the main loop, and linkage response to abnormal operating conditions." First, the fixed-frequency pumps in the fifth and eleventh circulation loops, in conjunction with the chiller, maintain the constant temperature reference of the cold and heat source regulating stations. Then, the variable-frequency water pumps adjust the flow rate and heat exchange intensity of the FWS and TCS main loops respectively, ultimately achieving precise control of the target parameters. Simulated operating conditions and waste heat dissipation serve as auxiliary control modules, working in conjunction with the main loop to complete full-condition adaptation. The control logic is shown in the appendix. Figure 3 In case of abnormal operating conditions, adjust the action of the actuators or trigger the shutdown protection. For example, in case of abnormal temperature in the cold source regulating station: Triggering conditions: deviation from the set value by ±2℃ (Level 1), ±5℃ (Level 2); approaching the freezing point of 20 wt% ethylene glycol or exceeding the safety threshold (Level 3).

[0055] Level 1: Reduce / increase the cooling capacity output of the fifth circulation loop unit (improve the loading and unloading level of the evaporator side of the chiller) or reduce / increase the heat exchange of the fourth circulation loop through the third heat exchanger. Level 2: Notify maintenance personnel to adjust the collaborative control strategy between the fourth and fifth loops; Level 3: When the temperature of the cold source regulating station approaches the freezing point or exceeds the safety threshold, immediately close the relevant valves of the fourth and fifth circulation loops and shut down the machine for protection to prevent the medium from solidifying and causing damage to the pipelines and heat exchangers.

[0056] 3. Specific implementation steps for each module 3.1 Implementation of Constant Temperature Control at the Cold Source Regulating Station As the system's cold source supply unit, the cold source regulating station provides constant-temperature cold source medium to the second, third, and fourth circulation loops. Its constant-temperature control is achieved through two stages: main cooling capacity supply and auxiliary fine-tuning. The main cooling capacity is provided by the fifth circulation loop, whose pump operates in a fixed-frequency mode, continuously delivering the medium to the evaporator side of the chiller. Cooling capacity regulation does not rely on water pump speed adjustment, but rather on the loading and unloading actions on the evaporator side of the chiller to change the unit's cooling output, stabilizing the medium temperature in the cold source regulating station at the set value, which can be adjusted down to a minimum of 3°C. Auxiliary fine-tuning is achieved through the fourth circulation loop, which is equipped with a variable-frequency pump that drives the medium in the cold source regulating station to the third plate heat exchanger. Through bidirectional heat exchange with the medium on the heat source regulating station side, the temperature of the cold source regulating station is finely compensated, offsetting temperature fluctuations in the main loop and further improving the stability of the cold source temperature.

[0057] 3.2 Implementation of Constant Temperature Control at Heat Source Regulating Station The heat source regulating station, as the system's heat source supply unit, provides a constant-temperature heat source medium to the eighth, ninth, and tenth circulation loops. Its temperature control includes three logics: main heat supply, auxiliary fine-tuning, and waste heat dissipation. The main heat supply is provided by the eleventh circulation loop, whose pump operates in a fixed-frequency mode, continuously delivering the medium to the chiller's condenser side. Heat regulation is achieved through loading and unloading actions on the chiller's condenser side, altering the unit's heat dissipation output to stabilize the medium temperature within the heat source regulating station at the set value, which can be adjusted up to 60℃. Auxiliary fine-tuning is achieved through the eighth circulation loop. The circulating loop is equipped with a variable frequency pump to drive the medium in the heat source regulating station to the third plate heat exchanger. It works in conjunction with the fourth circulating loop to complete bidirectional heat exchange and perform fine calibration of the temperature of the heat source regulating station. At the same time, a waste heat linkage cooling logic is set up. When the temperature of the heat source regulating station exceeds the set threshold, the variable frequency pump of the tenth circulating loop is started to transfer the excess heat to the fifth plate heat exchanger. Then, the heat is transferred to the cooling tower through the fixed frequency water pump of the sixth circulating loop. Outdoor air is used as a natural cold source to dissipate the waste heat to the external environment. After the temperature of the heat source regulating station drops back to the normal range, the cooling loop stops operating.

[0058] 3.3 Implementation of FWS-side inlet temperature and flow rate control The FWS-side control directly corresponds to the operating requirements of the CDU primary side, and is divided into two steps: flow closed-loop control and precise temperature control. Flow control is executed by the variable frequency pump in the first circulation loop. The target flow value is preset at the group control master station, and the flow sensor in the first circulation loop collects the actual flow data in real time and feeds it back to the master station for calculation. By adjusting the pump speed through variable frequency, the flow deviation is corrected in real time to achieve stable closed-loop control of the FWS-side flow. Temperature control is executed by the variable frequency pump in the second circulation loop. Using the constant temperature cold source provided by the cold source regulation station, the medium is driven to the first plate heat exchanger. By adjusting the pump speed of the second circulation loop, the heat exchange flow rate is changed, thereby adjusting the heat exchange capacity of the first plate heat exchanger to achieve precise control of the FWS-side inlet temperature and ensure that the temperature meets the standard when the medium enters the CDU primary side.

[0059] 3.4 Implementation of TCS-side inlet temperature and flow rate control The TCS-side control directly corresponds to the load requirements of the CDU secondary side. The control logic is compatible with the FWS side and is also divided into two steps: flow closed-loop control and precise temperature control. Flow control is executed by the variable frequency pump in the seventh circulation loop. The target flow value is preset at the group control master station. The flow sensor in the seventh circulation loop collects the actual flow data in real time and feeds it back to the master station for calculation. The flow deviation is corrected in real time by adjusting the pump speed through variable frequency, so as to achieve stable closed-loop control of the flow on the TCS side. Temperature control is executed by the variable frequency pump in the ninth circulation loop. The constant temperature heat source provided by the heat source regulation station drives the medium to the fourth plate heat exchanger. The heat exchange flow rate is changed by adjusting the pump speed in the ninth circulation loop, thereby adjusting the heat exchange capacity of the fourth plate heat exchanger, so as to achieve precise control of the inlet temperature on the TCS side and ensure that the temperature meets the standard when the medium enters the CDU secondary side.

[0060] 3.5 Implementation of CDU Built-in TCS Loop Simulation Operating Condition Control To address the operational simulation requirements of the CDU's built-in TCS loop, specialized control is achieved through the twelfth loop: When starting the simulation, the pump in the seventh loop is shut down, its valves are closed, the corresponding bypass pipeline is opened, and the original conventional loop path is cut off, allowing the medium to flow along the twelfth loop. The flow rate of this loop is not regulated by an external variable frequency pump but is directly controlled by the CDU's built-in pump, closely matching the actual operating characteristics of the built-in loop. The loop temperature is regulated by the variable frequency pump in the third loop, driving the cold source medium from the cold source regulating station to the second plate heat exchanger. By adjusting the pump speed in the third loop, the heat exchange capacity is changed, achieving precise control of the medium temperature under simulated conditions and completely replicating the operating state of the CDU's built-in TCS loop.

[0061] 4. System linkage control and operation assurance All the above-mentioned module control logics are uniformly coordinated by the group control master station. Signal communication and action linkage are achieved between each loop and each execution component, with no independent operation conflicts. The FWS and TCS main loop parameters are given priority closed loop, the cold and heat source regulation station ensures the medium temperature reference in real time, and auxiliary logic such as waste heat dissipation and temperature fine adjustment are automatically triggered as needed, without the need for manual intervention throughout the process. The system's temperature sensors and differential pressure sensors monitor the parameters of each key node in real time. When parameters exceed the standard or equipment malfunctions, the group control master station can respond in a timely manner, adjust the actions of the execution components or trigger shutdown protection to ensure the long-term stable operation of the system and meet the control requirements of various test conditions.

[0062] In summary, the liquid cooling unit performance testing system constructed in this embodiment uses a high-power closed-loop heat exchange simulation module to replace the traditional electric heating dummy load, breaking through the upper limit of power bearing capacity. It can stably adapt to the full-load, extreme load and dynamic variable load full-condition testing of megawatt-level large CDUs, completely solving the problem of insufficient power of traditional electric heating dummy loads, and meeting the complete performance testing requirements of large CDUs in high-power scenarios such as data centers and supercomputing centers.

[0063] Based on this, the testing system is equipped with an energy recovery and recycling mechanism. By using bidirectional heat exchange between cold and heat sources, waste heat recovery, and natural cold source-assisted heat dissipation, it replaces the traditional direct consumption and discharge mode of electrical energy, realizes efficient recycling of energy in the testing process, significantly reduces energy consumption throughout the testing process, reduces testing operating costs, and conforms to the industry development trend of green and energy-saving testing.

[0064] Furthermore, through the active wide-temperature-range cold source control module, the active cooling of the chiller replaces the passive cooling tower heat dissipation, eliminating the limitations of external environmental temperature, humidity, wind speed and other climatic conditions. The cold source temperature can be precisely adjusted over a wide range, down to as low as 3℃, covering the simulation of working conditions in the full temperature range from low temperature to high temperature. This completely solves the technical pain points of traditional cooling towers, such as limited temperature range and heat dissipation failure in summer, ensuring that testing can be carried out normally throughout the year and all seasons.

[0065] Meanwhile, this embodiment establishes independent and non-interfering FWS-side cold source medium circulation loop and TCS-side load medium circulation loop. The two loops can be independently filled with different types of coolant, flexibly realizing accurate simulation of various medium combination scenarios such as water / ethylene glycol aqueous solution, ethylene glycol aqueous solution / ethylene glycol aqueous solution, ethylene glycol aqueous solution / propylene glycol aqueous solution, and special heat transfer fluid / water. This enables full-scenario multi-medium compatibility testing, comprehensively verifying the CDU's operating performance, heat exchange efficiency, and sealing compatibility under different medium combinations. The test results are highly consistent with actual engineering conditions.

[0066] In addition, the testing system is equipped with a high-precision dynamic parameter control and data acquisition system. Through variable frequency speed regulation and unit linkage control, it realizes hierarchical closed-loop control, which can accurately simulate complex dynamic operating conditions with variable load, variable flow, variable temperature, and variable medium type. The parameters of each loop are collected in real time, and the group control master station performs unified calculation and issues commands to build a full-process linkage closed-loop control system. It can comprehensively obtain the core performance parameters of large CDUs, and the testing accuracy and comprehensiveness are significantly better than traditional solutions.

[0067] Therefore, the liquid cooling unit performance testing system in this embodiment can fully meet the full-process testing needs of large CDUs in R&D, factory quality control and performance calibration.

[0068] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A liquid cooling unit performance testing system, wherein the liquid cooling unit has an FWS side and a TCS side, characterized in that, The testing system includes: Cold source regulating station, heat source regulating station; The first heat exchanger is connected to the FWS side on one side through a first circulation loop and to the cold source regulating station on the other side through a second circulation loop, so as to realize heat exchange between the FWS side and the cold source regulating station. The fourth heat exchanger is connected to the TCS side on one side through the seventh circulation loop and to the heat source regulating station on the other side through the ninth circulation loop, which is used to realize heat exchange between the TCS side and the heat source regulating station. The second heat exchanger is connected to the cold source regulating station on one side through the third circulation loop, and to the fourth heat exchanger side of the seventh circulation loop on the other side through the twelfth circulation loop, which is used to realize heat exchange between the cold source regulating station and the TCS side. The third heat exchanger is connected to the cold source regulating station on one side through the fourth circulation loop and to the heat source regulating station on the other side through the eighth circulation loop, which is used to realize heat exchange between the cold source regulating station and the heat source regulating station. The refrigeration unit has its evaporator side connected to the cold source regulating station via the fifth circulation loop to regulate the temperature of the medium within the cold source regulating station, and its condenser side connected to the heat source regulating station via the eleventh circulation loop to regulate the temperature of the medium within the heat source regulating station.

2. The liquid cooling unit performance testing system according to claim 1, characterized in that, Also includes: The first injection tank is connected to the first circulation loop and is used to inject circulating medium into the first circulation loop; The second injection tank is connected to the seventh circulation loop and is used to inject circulating medium into the seventh circulation loop.

3. The liquid cooling unit performance testing system according to claim 2, characterized in that, The circulating medium in the first injection tank and the second injection tank is one of water, ethylene glycol aqueous solution, and propylene glycol aqueous solution, respectively.

4. The liquid cooling unit performance testing system according to claim 1, characterized in that, Also includes: The first closed-type airbag expansion tank is connected to the first circulation loop and is used to maintain pressure and compensate for or absorb volume changes caused by thermal expansion and contraction of the first circulation loop. The second closed-loop airbag expansion tank is connected to the seventh circulation loop and is used to maintain pressure and compensate for or absorb volume changes caused by thermal expansion and contraction of the seventh circulation loop.

5. The liquid cooling unit performance testing system according to claim 1, characterized in that, It also includes a fifth heat exchanger and a cooling tower. One side of the fifth heat exchanger is connected to the heat source regulating station through the tenth circulation loop, and the other side is connected to the cooling tower through the sixth circulation loop, which is used to realize the discharge of waste heat from the heat source regulating station.

6. The liquid cooling unit performance testing system according to claim 5, characterized in that, Pumps are installed in all eleventh to first circulation loops.

7. The liquid cooling unit performance testing system according to claim 6, characterized in that, The pumps in the fifth, sixth, and eleventh circulation loops are fixed-frequency pumps; The pumps in the first, second, third, fourth, seventh, eighth, ninth, and tenth circulation loops are variable frequency pumps.

8. The liquid cooling unit performance testing system according to claim 6, characterized in that, The seventh circulation loop also has a bypass line connected in parallel with its pump; among which, When using the second heat exchanger to achieve heat exchange between the cold source regulating station and the TCS side, the pump in the seventh circulation loop does not work, the bypass pipeline is open, and the return flow is controlled by the built-in pump of the liquid cooling unit. When the heat source regulating station and the TCS side are exchanged using the fourth heat exchanger, the pump in the seventh circulation loop is working, and the bypass pipeline is not connected.

9. The liquid cooling unit performance testing system according to claim 1, characterized in that, Temperature sensors and differential pressure sensors are installed at the inlet and outlet positions of the connecting pipe section between the first circulation loop and the FWS side. Temperature sensors and differential pressure sensors are installed at the inlet and outlet positions of the connecting pipe section between the seventh circulation loop and the TCS side.

Images