A wind and liquid integrated cabinet dummy load

Abstract

The application discloses a wind-liquid integrated cabinet dummy load and relates to the technical field of data center heat dissipation system test equipment. The dummy load comprises a cabinet body, an electric total control module, a wind-liquid composite load module and a liquid total control module integrated in the cabinet body, and each module is arranged in a laminated mode along the height direction of the cabinet body and is detachably connected through a standardized interface. The electric total control module takes a PLC controller as a core, and is integrated with a touch screen and a remote communication interface; the liquid total control module is integrated with a liquid supply and return main pipe, a first electric regulating valve and a sensor assembly; each group of the wind-liquid composite load module comprises a liquid cooling load unit and an air cooling load unit, and alloy tubular resistors and nichrome resistor elements are respectively adopted. The application realizes 3kW step power grading switching through a shunt load contactor group, realizes heat dissipation self-adaptation through liquid path double-end monitoring and PID closed-loop control of the second electric regulating valve, and has the advantages of high-precision power regulation, composite load simulation, intelligent temperature control, modularized rapid deployment, multiple safety protection and the like.

Description

Technical Field

[0001] This invention relates to the field of data center liquid cooling system testing technology, specifically to a fan-liquid integrated cabinet dummy load, which is particularly suitable for load testing, performance verification, delivery acceptance, and fault simulation of high power density liquid-cooled servers, cooling distribution units, and the entire liquid cooling system. Background Technology

[0002] With the rapid development of large-scale AI model training, high-density computing clusters, and high-power industrial converters, the power density of server racks continues to rise, with 80kW and above high-power-density servers becoming the mainstream configuration for data centers. Cold-plate liquid cooling technology, with its core advantages of high heat exchange efficiency and low PUE (Power Usage Effectiveness), has become the mainstream solution for cooling high-power-density servers. Liquid-cooled dummy loads, as core dedicated testing equipment for liquid-cooled system performance verification, CDU load testing, system delivery acceptance, and maintenance troubleshooting, directly determine the commissioning efficiency and long-term operational reliability of the liquid-cooled system based on their load simulation accuracy, thermal adaptability, and ease of maintenance. They are crucial supporting equipment for the construction and maintenance of liquid-cooled data centers.

[0003] In existing technologies, most liquid-cooled dummy load devices employ only a single liquid-cooling or single-air-cooling architecture, failing to achieve coordinated simulation of combined liquid-cooling and air-cooling loads. However, current mainstream liquid-cooled servers generally employ a combined liquid-cooling and air-cooling cooling mode during actual operation—high-heat components such as the CPU and GPU are cooled by cold-plate liquid cooling, while auxiliary components such as power modules, memory modules, and hard drives still require air cooling. Dummy loads with a single cooling architecture cannot accurately reproduce the combined heat dissipation conditions of a server, leading to discrepancies between test results and actual operating conditions. Furthermore, the minimum power adjustment step of existing devices is generally greater than 2kW, which cannot meet the requirements of high-precision load simulation, resulting in significant deviations in test data and making it difficult to accurately reproduce the actual load state of the server.

[0004] Existing equipment mostly employs a fixed-flow cooling scheme, lacking intelligent temperature control and flow rate linkage adjustment capabilities, and cannot automatically adapt the cooling flow rate according to changes in load power. When the load power changes abruptly, the fixed-flow cooling scheme is prone to insufficient heat exchange efficiency or over-cooling, frequently resulting in excessive medium temperature rise, severely impacting the continuity and accuracy of testing. Furthermore, the lack of comprehensive real-time monitoring of coolant inlet and outlet temperatures, pressures, and flow rates makes it impossible to accurately calculate actual heat dissipation power, leading to insufficient accuracy in operational condition monitoring.

[0005] Most existing products do not use standardized quick-connect clamp interfaces, resulting in cumbersome and inefficient pipe connection operations and lengthy on-site installation times. Inappropriate material selection for fluid channels and a lack of corrosion and scale prevention optimization for common liquid cooling media such as ethylene glycol mixtures lead to risks of leakage, corrosion, and pipe blockage after long-term operation, significantly increasing maintenance costs and downtime. Furthermore, existing equipment often employs a distributed deployment scheme, requiring separate on-site installation of electrical control cabinets, load cabinets, and fluid circuit components, making the setup of testing systems complex.

[0006] Existing equipment generally lacks multiple protection functions and intelligent monitoring modules. Electrical safety protection relies solely on basic fuses, lacking early warning and protection mechanisms for faults such as liquid cooling medium leakage and abnormal temperature rise. Furthermore, most equipment lacks casters and forklift mounting points, resulting in extremely low efficiency in handling and deployment within data center server rooms. The overall equipment lacks modular design, requiring separate inspections of electrical, hydraulic, and control units for maintenance, leading to high operating costs and low efficiency.

[0007] Existing liquid-cooled dummy loads are mostly designed for open cooling water systems and are not optimized for the low flow resistance, microchannel anti-clogging, and high cleanliness requirements of closed liquid cooling systems. They suffer from problems such as high pressure drop, poor adaptability, and high maintenance costs, and cannot meet the core requirements of standardized acceptance and full-cycle stability testing for 80kW-class high-power liquid-cooled servers.

[0008] In summary, developing a liquid-cooled integrated cabinet dummy load with composite load simulation capabilities, high-precision power regulation, intelligent temperature control protection, and efficient and convenient operation and maintenance has become the key to breaking through the bottleneck of liquid cooling testing technology and ensuring the reliable operation of liquid cooling systems. Summary of the Invention

[0009] To solve the above technical problems, the present invention provides a fan-liquid integrated cabinet dummy load, including a cabinet and an electrical control module, at least one set of fan-liquid composite load module and liquid control module integrated in the cabinet; The electrical control module, the air-liquid composite load module, and the liquid control module are stacked sequentially along the height of the cabinet, and the modules are detachably connected through standardized electrical interfaces and liquid quick-connect interfaces. The electrical control module is based on a PLC controller and integrates a touch screen human-machine interface and a remote communication interface. It is electrically connected to each of the wind-liquid composite load modules through the standardized electrical interface. The liquid control module integrates a liquid supply main pipe, a liquid return main pipe, an electric regulating valve, and sensor components installed on the liquid supply main pipe and the liquid return main pipe. It is connected to the liquid circuit of each of the air-liquid composite load modules through the liquid circuit quick-connect interface. Each of the air-liquid composite load modules includes a liquid-cooled load unit and an air-cooled load unit. The liquid-cooled load unit includes a liquid-cooled load resistor group and liquid pipelines, and the air-cooled load unit includes an air-cooled load resistor element and a forced air-cooled fan.

[0010] Preferably, the main electrical control module further includes a three-phase incoming fuse, a three-phase main contactor, a branch load contactor group, a three-phase leakage current protector, and a three-phase voltage acquisition module; The input terminal of the three-phase incoming fuse is connected to an external three-phase AC power supply via an industrial connector. The output terminal of the three-phase incoming fuse is connected to the input terminal of the three-phase main contactor. The output terminal of the three-phase main contactor is connected to the input terminal of the branch load contactor group and the input terminal of the three-phase leakage current protector, respectively. Each output terminal of the branch load contactor group is connected to the liquid-cooled load resistor group and the air-cooled load resistor element of each of the air-liquid composite load modules, respectively. The output terminal of the three-phase leakage current protector is connected to the three-phase voltage acquisition module. The three-phase leakage current protector also transmits its detection signal to the PLC controller. The PLC controller is connected to the touch screen human-machine interface, the three-phase main contactor, the branch load contactor group, the three-phase leakage current protector, the three-phase voltage acquisition module, and the electric regulating valve and sensor assembly of the hydraulic control module.

[0011] Preferably, the shunt load contactor group includes multiple shunt contactors, each of which controls the on / off state of the liquid-cooled load resistor group and the air-cooled load resistor element of a group of the air-liquid composite load modules. The PLC controller controls the corresponding number of branch contactors to close or open according to the set target power value, so as to realize the power level switching with a minimum step of 3kW, and the power adjustment range is continuously adjustable from 3kW to 80kW.

[0012] Preferably, the main supply pipe of the liquid control module is equipped with an electric regulating valve, a liquid supply temperature sensor, a liquid supply pressure sensor and a liquid supply flow meter, and the return liquid main pipe is equipped with a return liquid temperature sensor, a return liquid pressure sensor and a return liquid flow meter; The main supply pipe and the main return pipe are respectively provided with quick-connect chuck interfaces for quick connection to an external liquid cooling source; The main liquid supply pipe is connected to the inlet end of the liquid pipeline of each of the air-liquid composite load modules through the liquid supply branch pipes, and the main return liquid pipe is connected to the outlet end of the liquid pipeline of each of the air-liquid composite load modules through the return liquid branch pipes.

[0013] Preferably, the PLC controller calculates the actual heat dissipation power of the liquid-cooled load based on the parameters collected in real time by the liquid supply temperature sensor, the liquid supply pressure sensor, the liquid supply flow meter, the return liquid temperature sensor, the return liquid pressure sensor, and the return liquid flow meter, and compares the actual heat dissipation power with the target power value. The opening of the electric regulating valve is dynamically adjusted through a PID control algorithm to dynamically match the actual heat dissipation power with the load power.

[0014] Preferably, each group of the air-liquid composite load modules further includes a module housing, the liquid-cooled load unit is disposed in the lower region of the module housing, and the air-cooled load unit is disposed in the upper region of the module housing; The liquid-cooled load resistor group is composed of multiple alloy tubular resistor elements connected in parallel or in series. Each alloy tubular resistor element is encapsulated in a sealed housing, which is immersed in the cooling medium of the liquid pipeline. The liquid pipeline is made of stainless steel and the inner wall is passivated for corrosion protection. The inlet and outlet ends of the liquid pipeline are respectively equipped with quick-connect chuck interfaces. The air-cooled load resistor element is made of nickel-chromium alloy resistance wire and is fixedly installed on an insulating bracket. It is located in the air duct of the module housing, and the forced air-cooling fan is located at the air outlet of the air duct.

[0015] Preferably, the remote communication interface includes an Ethernet communication interface and an RS485 communication interface. The Ethernet communication interface supports the Modbus TCP communication protocol, and the RS485 communication interface supports the Modbus RTU communication protocol.

[0016] Preferably, the control panel of the electrical control module is equipped with a rotary switch and an emergency stop switch. The rotary switch is connected to the PLC controller for signal control of the equipment, and is used to start, stop and switch modes. The emergency stop switch is connected in series in the control circuit of the three-phase main contactor and is used to cut off the load power supply in an emergency.

[0017] Preferably, both the liquid-cooled load resistor group and the air-cooled load resistor element are purely resistive loads.

[0018] Preferably, a butterfly valve is provided on the main supply pipe and the main return pipe respectively. The butterfly valve is located at the end of the main supply pipe and the main return pipe near the quick-release chuck interface, and is used to cut off the liquid circuit during maintenance. The air-cooled load unit also includes an air duct temperature sensor installed in the air duct for real-time monitoring of the operating temperature of the air-cooled load.

[0019] The technical effects and advantages of this invention are as follows: 1. This invention adopts a liquid-cooled load + air-cooled load composite architecture, integrating the liquid-cooled load unit and the air-cooled load unit into the same air-liquid composite load module. It can simultaneously simulate the liquid-cooled heat dissipation part and the air-cooled heat dissipation part of the liquid-cooled server, and truly restore the actual operating conditions of the server's "liquid cooling + air cooling" coordinated heat dissipation. It overcomes the technical defect that the existing single cooling architecture fake load cannot truly simulate the composite heat dissipation conditions.

[0020] 2. This invention achieves multi-level combination switching with a minimum step of 3kW through a shunt load contactor group. The power adjustment range covers 3kW-80kW and is continuously adjustable. It has high power adjustment accuracy and small step size, which can meet the fine testing needs of different power levels and effectively solves the technical problems of large power adjustment step size and large test data deviation in existing equipment.

[0021] 3. This invention achieves real-time monitoring of the coolant inlet and outlet in all dimensions through the supply temperature sensor, supply pressure sensor, supply flow meter, return temperature sensor, return pressure sensor, and return flow meter of the liquid control module. Combined with the PID closed-loop control of the second electric regulating valve, the coolant flow rate is automatically adapted according to the load power change, ensuring optimal heat exchange efficiency and controllable medium temperature rise, which greatly improves the continuity and accuracy of the test.

[0022] 4. This invention integrates the electrical control module, the air-hydraulic composite load module, and the liquid control module into the same cabinet, adopting a modular stacked frame structure. The modules are detachably connected through standardized electrical interfaces and liquid quick-connect interfaces, allowing for rapid assembly and deployment on site, which greatly simplifies the setup process of the test system.

[0023] 5. The entire liquid circuit system of this invention adopts a quick-connect chuck standard interface, making pipeline connection operation simple and quick; the liquid pipeline is made of stainless steel and the inner wall is passivated for corrosion protection, which effectively solves the corrosion and blockage problems of commonly used liquid cooling media such as ethylene glycol mixture during long-term operation, and greatly reduces maintenance costs and downtime risks.

[0024] 6. This invention achieves accurate calculation and traceability of the entire process of load output power and actual heat dissipation power by using dual-channel temperature, pressure and flow monitoring of the liquid control module (temperature, pressure and flow sensors are arranged at both the liquid supply end and the liquid return end), combined with the three-phase voltage and current acquisition of the electrical control module, thus ensuring the authenticity and reliability of the test data.

[0025] 7. This invention integrates multiple safety mechanisms, including leakage detection (judged by abnormal signals from liquid circuit sensor components), overpressure protection (monitored by pressure sensors), overcurrent protection (monitored by current acquisition modules), overtemperature protection (monitored by temperature sensors), leakage protection (implemented by three-phase leakage current protectors), and interlocking shutdown. It constructs a full-link protection system from both liquid and electrical dimensions. When any abnormality is detected, the load power supply is automatically cut off to eliminate potential safety hazards.

[0026] 8. This invention adopts a dual-control architecture of local touch screen + remote host computer, is compatible with Modbus TCP and RS485 communication protocols, supports synchronous cluster control of multiple devices, unified parameter setting, and completes sudden loading operations in seconds, perfectly adapting to the clustered and large-scale testing needs of large data centers and power systems.

[0027] 9. The liquid-cooled load resistor group and the air-cooled load resistor element of the present invention are both purely resistive loads, which only consume active power and do not generate reactive current. They will not interfere with the protection system of the equipment under test, nor will they cause additional burden to the power grid. Their operation is stable and reliable.

[0028] 10. The integrated cabinet design of this invention simplifies on-site deployment and eliminates the need for complex wiring and piping construction; the modular structure allows each module to be independently disassembled, installed, and repaired, making maintenance and operation convenient; the local + remote dual-mode human-machine interaction provides convenient operation, significantly improves testing and maintenance efficiency, and reduces the total lifecycle cost. Attached Figure Description

[0029] Figure 1 This is a side view of the dummy load of the integrated air-liquid cabinet provided in the embodiment of this application; Figure 2 This is a front view of the dummy load of the integrated air-liquid cabinet provided in the embodiments of this application; Figure 3 This is a rear view of the dummy load of the integrated air-liquid cabinet provided in the embodiments of this application; Figure 4 This is a top view of the dummy load of the integrated air-liquid cabinet provided in the embodiment of this application; Figure 5 This is a schematic diagram illustrating the working principle of the integrated air-liquid cabinet dummy load provided in the embodiments of this application; Figure 6 This is the main circuit electrical schematic diagram of the dummy load of the integrated air-liquid cabinet provided in the embodiment of this application.

[0030] In the diagram: 1. Main electrical control module; 2. Combined air-liquid load module; 3. Industrial connector; 4. Display screen; 5. Rotary switch; 6. Emergency stop switch; 7. Connector; 8. Exhaust valve; 9. Main liquid control module; 10. First electric regulating valve; 11. Liquid supply quick-release chuck interface; 12. Liquid return quick-release chuck interface; 13. Liquid supply temperature sensor; 14. Liquid supply pressure sensor; 15. Liquid supply flow meter; 16. Liquid return temperature sensor; 17. Liquid return pressure sensor; 18. Liquid return flow meter; 19. Second electric regulating valve; 20. Butterfly valve; 21. Load assembly; 22. Three-phase incoming fuse; 23. Three-phase main contactor; 24. Branch load contactor group; 25. Liquid-cooled load resistor group; 26. Three-phase leakage current protector; 27. Three-phase voltage acquisition module. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose. like Figures 1 to 3 As shown, this embodiment provides a fan-liquid integrated cabinet dummy load, including a cabinet and an electrical control module 1, a fan-liquid composite load module 2 and a liquid control module 9 integrated in the cabinet.

[0032] The cabinet adopts a modular stacked frame structure, with overall dimensions of 600mm width, 1200mm depth, and 2200mm height, conforming to standard data center cabinet specifications. The main electrical control module 1 is located at the top of the cabinet, six sets of air-hydraulic composite load modules 2 are stacked sequentially in the middle of the cabinet, and the main hydraulic control module 9 is located at the bottom. All modules are detachably connected via standardized electrical interfaces 7 and quick-connect hydraulic interfaces, allowing for rapid on-site assembly. Load-bearing casters and forklift mounting holes are located at the four corners of the cabinet's bottom for easy movement and positioning within the data center.

[0033] The equipment has a rated input of AC 380V / 3P / 50Hz and a total power of 80kW. Power adjustment is in 3kW increments and supports continuous adjustment from 3kW to 80kW. Before leaving the factory, the equipment undergoes appearance and dimensional inspection, insulation resistance testing, airtightness testing, pipeline cleanliness testing, and full-function verification to meet the requirements for indoor installation and long-term continuous operation in data center server rooms.

[0034] like Figure 1 and Figure 2As shown, the main control module 1 has a 7-inch color touchscreen display 4, a rotary switch 5, and an emergency stop switch 6 on its panel. The touchscreen display 4 is used to display the equipment's operating parameters (including voltage, current, power, temperature, pressure, flow rate, etc.) and receive user touch operation commands. The rotary switch 5 is used to start, stop, and switch modes (local mode / remote mode) of the equipment. The emergency stop switch 6 is a red mushroom-shaped button connected in series in the control circuit of the three-phase main contactor 23. In an emergency, pressing it will cut off the power supply to the load assembly 21, which includes a liquid-cooled load resistor group and an air-cooled load resistor element.

[0035] The rear end of the main electrical control module 1 has two industrial connectors 3, which are used to connect to the input terminal of an external three-phase AC power supply and the output terminal of an external device, respectively. The main electrical control module 1 is connected to the external three-phase AC power supply through the industrial connectors 3, and is electrically connected to each of the air-hydraulic composite load modules 2 through standardized electrical interfaces 7.

[0036] like Figure 3-5 As shown, the liquid control module 9 integrates a main liquid supply pipe, a main liquid return pipe, a first electric regulating valve 10, an exhaust valve 8, and a sensor assembly. The rear end of the liquid control module 9 is equipped with a quick-connect chuck interface 11 for liquid supply and a quick-connect chuck interface 12 for quick connection to the liquid supply and return lines of an external liquid cooling source. The liquid control module 9 connects to the liquid circuits of each air-liquid composite load module 2 via the quick-connect interfaces.

[0037] Specifically, the quick-release chuck interface is a quick-connect interface that conforms to ISO 2852 or Tri-Clamp standards, which quickly and sealably connects two components with connecting pipes using clamps.

[0038] The main supply pipe is equipped with a quick-connect chuck interface 11, a first electric regulating valve 10, a supply temperature sensor 13, a supply pressure sensor 14, and a supply flow meter 15, arranged sequentially. The main return pipe is equipped with a quick-connect chuck interface 12, an exhaust valve 8, a return temperature sensor 16, a return pressure sensor 17, and a return flow meter 18, arranged sequentially. The return temperature sensor 16, return pressure sensor 17, and return flow meter 18 are connected in series on the main return pipe to monitor return parameters in real time, allowing the PLC to calculate the actual heat dissipation power. A differential pressure sensor (not shown in the figure) is also installed between the supply and return main pipes to monitor the pressure difference between the supply and return liquids in real time. A butterfly valve 20 is installed on both the supply and return main pipes. The butterfly valve 20 is located near the quick-connect interface on the return main pipe and is used to cut off the liquid path during maintenance.

[0039] The first electric regulating valve 10 is an electric proportional regulating valve. Its valve core opening is automatically controlled by the PLC controller using a PID algorithm based on the power of the load assembly 21 and sensor feedback signals, thereby achieving precise regulation of the coolant flow rate. The regulation accuracy of the first electric regulating valve 10 is ±1%, and the response time is less than 2 seconds.

[0040] In this embodiment, the first electric regulating valve 10 is an electric regulating valve configured for the liquid main module. It is installed on the liquid main pipe and is used to adjust the opening of the main pipe according to the overall system demand, thus playing a role in global flow control. The second electric regulating valve is an electric regulating valve configured for the 19 air-liquid composite load module. It is installed on the branch pipe connected to this load module and is used to adjust the opening of the branch pipe according to the independent demand of this load module, thus playing a role in local flow distribution. Both are electric regulating valves. The first electric valve focuses on coarse adjustment of the overall flow, while the second electric valve focuses on fine adjustment of the branch flow. The two work together to ensure the stability of the overall system flow and to meet the personalized flow requirements of each load module.

[0041] like Figure 4 As shown, each group of air-liquid composite load modules 2 includes a module housing and a liquid-cooled load unit and an air-cooled load unit disposed within the module housing.

[0042] The module housing is a rectangular box structure, constructed from 1.5mm thick cold-rolled steel plate through bending and welding, with a rust-proof coating. The front face of the housing features a module panel equipped with status indicator lights (green for normal operation, yellow for standby, and red for fault) and a manual operation interface. The rear face has a standardized electrical interface 7 and a quick-connect fluid interface. Ventilation louvers are located on the left and right sides for air intake and exhaust during air-cooling. The top and bottom surfaces of the housing feature stacking positioning structures (positioning pins and holes) to ensure accurate positioning and stable connection when multiple layers are stacked.

[0043] The liquid-cooled load unit is located in the lower part of the module housing and includes a liquid-cooled load resistor group 25 and liquid piping. The liquid-cooled load resistor group 25 consists of multiple alloy tubular resistor elements connected in parallel, with a total power of 10kW. Each alloy tubular resistor element is encapsulated in a corrosion-resistant, highly thermally conductive stainless steel sealed housing, which is immersed in the cooling medium of the liquid piping. The heat generated by the resistor elements is directly transferred to the cooling medium through the sealed housing. The liquid piping is DN25 stainless steel piping with passivated anti-corrosion treatment on the inner wall. Quick-connect chuck interfaces (KF25 standard) are provided at both the inlet and outlet ends of the piping. The liquid piping is arranged in an S-shaped meandering pattern at the bottom of the module housing to increase the contact area between the cooling medium and the sealed housing and to extend the heat exchange time.

[0044] The air-cooled load unit is located in the upper part of the module housing and includes an air-cooled load resistor element and a forced-air cooling fan. The air-cooled load resistor element is made of nickel-chromium alloy resistance wire and is fixedly mounted on a ceramic insulating bracket, with a total power of 3.33kW. The air-cooled load resistor element is located within the air duct of the module housing. The air duct draws in air from one side of the module housing through ventilation louvers, passes over the surface of the resistor element, and exits from the other side through ventilation louvers. The forced-air cooling fan is an axial flow fan, located at the air outlet of the air duct, with an airflow of not less than 200 CFM and a total pressure of not less than 100 Pa. The temperature rise at the air outlet is controlled below 30K.

[0045] Specifically, the forced air-cooled fan is an axial flow fan, located at the air outlet of the air duct to extract the hot air flowing through the air-cooled load resistor element, or located at the air inlet of the air duct to blow cold air from the outside into the air duct.

[0046] The air-cooled load unit also includes an air duct temperature sensor installed within the air duct to monitor the operating temperature of the air-cooled load in real time and prevent overheating. The liquid-cooled load unit also includes a liquid cooling medium temperature sensor installed within a sealed housing to monitor the temperature of the liquid cooling medium in real time.

[0047] Figure 6 As shown, the main circuit electrical connection of the main control module 1 is as follows: The input terminal of the three-phase incoming fuse 22 is connected to an external three-phase AC power supply (AC 380V / 3P / 50Hz) via industrial connector 3. The rated current of the three-phase incoming fuse 22 is 200A, used for short-circuit protection of the main circuit. The output terminal of the three-phase incoming fuse 22 is connected to the input terminal of the three-phase main contactor 23. The rated current of the three-phase main contactor 23 is 200A, the coil voltage is AC 220V, and its activation and deactivation are controlled by a PLC controller.

[0048] The output terminals of the three-phase main contactor 23 are connected to the input terminals of the branch load contactor group 24 and the input terminal of the three-phase residual current device 26, respectively. The branch load contactor group 24 consists of multiple branch contactors, each with a rated current of 32A, which respectively control the switching on and off of the liquid-cooled load resistor group 25 and the air-cooled load resistor element of a set of air-liquid composite load modules 2. Each output terminal of the branch load contactor group 24 is connected to the liquid-cooled load resistor group 25 and the air-cooled load resistor element of each air-liquid composite load module 2, respectively.

[0049] Each branch contactor in the branch load contactor group 24 does not control the entire air-liquid composite load module, but rather controls a sub-unit or specific combination of the liquid-cooled load resistor group and the air-cooled load resistor element within the module. By switching on and off in different combinations of multiple contactors, a 3kW step adjustment is achieved.

[0050] Specifically, the six sets of combined air-cooled and liquid-cooled load modules are not all activated simultaneously. Instead, the load is activated in 3kW increments by controlling different numbers of contactors in the branch load contactor group, thus achieving continuous adjustment from 3 to 80kW. For example, activating a portion of the resistance from two liquid-cooled load units and a portion of the resistance from one air-cooled load unit combines to form a 3kW load.

[0051] The three-phase residual current device 26 has a rated current of 200A, a residual current operating current of 30mA, and an operating time of no more than 0.1 seconds. It is used for leakage protection of equipment. The output terminal of the three-phase residual current device 26 is connected to the three-phase voltage acquisition module 27. The three-phase voltage acquisition module 27 is used to acquire three-phase voltage signals in real time and transmit them to the PLC controller. The three-phase current signals are acquired through current transformers (not shown in the figure) installed on each phase line and transmitted to the PLC controller.

[0052] The control system connection of the main electrical control module 1 is as follows: The PLC controller serves as the core control unit and is connected to the touch screen human-machine interface 4, the three-phase main contactor 23, the branch load contactor group 24, the three-phase leakage current protector 26, the three-phase voltage acquisition module 27, the second electric regulating valve 19, the liquid supply temperature sensor 13, the liquid supply pressure sensor 14, the liquid supply flow meter 15, the return liquid temperature sensor 16, the return liquid pressure sensor 17, and the return liquid flow meter 18.

[0053] The PLC controller adopts the Siemens S7-1200 series, possessing powerful logic control and analog signal processing capabilities. The PLC controller has a built-in PID control function block for implementing closed-loop control of the second electric regulating valve 19. The PLC controller also integrates Ethernet and RS485 communication interfaces. The Ethernet communication interface supports the Modbus TCP communication protocol for data exchange with a remote host computer; the RS485 communication interface supports the Modbus RTU communication protocol for communication with expansion devices.

[0054] The touchscreen HMI 4 is a 7-inch color TFT touchscreen with a resolution of 800×480, connected to the PLC controller via an Ethernet interface. The touchscreen HMI 4's display interface includes a main operation interface, a parameter setting interface, an alarm recording interface, and a curve display interface. The main operation interface displays all operating parameters in real time, including three-phase voltage, three-phase current, active power, power factor, liquid cooling circuit supply temperature, return temperature, supply pressure, return pressure, supply flow rate, return flow rate, and differential pressure. The parameter setting interface is used to set target power values, alarm thresholds, PID parameters, etc. The alarm recording interface is used to record and display historical alarm information. The curve display interface displays the trend curves of each parameter.

[0055] Rotary switch 5 is a three-position selector switch (stop / local / remote) that connects to the digital input terminal of the PLC controller. When rotary switch 5 is in the "stop" position, the equipment is in a stopped state; when it is in the "local" position, the equipment is operated locally through the touch screen human-machine interface 4; when it is in the "remote" position, the equipment receives control commands from the remote host computer through the remote communication interface.

[0056] Emergency stop switch 6 is a self-locking mushroom-shaped push button, with its normally closed contact connected in series in the coil power supply circuit of the three-phase main contactor 23. When emergency stop switch 6 is pressed, the coil of the three-phase main contactor 23 is de-energized, the three-phase main contactor 23 opens, and the power supply to all loads is cut off. Resetting emergency stop switch 6 requires rotating it to unlock it.

[0057] The working process of the dummy load of the integrated air-liquid cabinet in this embodiment is as follows: (a) System startup The operator rotates rotary switch 5 to the "Local" position, and the equipment is powered on and started. The PLC controller executes a self-test program to check whether the signals of each sensor are normal, whether each contactor is in the open state, and whether there is a leak alarm in the hydraulic system. After the self-test passes, the touch screen human-machine interface 4 displays the main operating interface, and the equipment enters standby mode.

[0058] (II) Power setting and loading The operator inputs the target power value (e.g., 60kW) into the parameter setting interface of the touch screen human-machine interface 4 and clicks the "Start Loading" button. After receiving the loading command, the PLC controller calculates the required number of load levels to be activated based on the target power value of 60kW and the single load level of 3kW, which is 20 levels (60÷3=20). According to the principle of three-phase balance, the PLC controller selects 20 branch contactors from the branch load contactor group 24 to close, putting the corresponding liquid-cooled load resistor group 25 and air-cooled load resistor element into operation. At the same time, the PLC controller sends an opening command to the second electric regulating valve 19 of the liquid control module 9. The second electric regulating valve 19 opens to the preset initial opening, and the cooling medium begins to flow through the liquid-cooled load unit.

[0059] 3kW is the minimum step for overall power regulation. Each switching operation simultaneously puts on or cuts off the liquid-cooled load unit and the air-cooled load unit in a set of air-liquid composite load modules, maintaining a fixed power ratio between the two.

[0060] (III) Closed-loop regulation and stable operation The liquid-cooled load resistor group 25 and the air-cooled load resistor element begin to generate heat after being energized. The heat generated by the liquid-cooled load resistor group 25 is transferred to the cooling medium flowing through the liquid pipeline through the sealed housing. After the temperature of the cooling medium rises, it returns to the external liquid cooling source through the return main pipe. The liquid supply temperature sensor 13, liquid supply pressure sensor 14, and liquid supply flow meter 15 collect the temperature, pressure, and flow parameters at the liquid supply end in real time, and the return liquid temperature sensor 16, return liquid pressure sensor 17, and return liquid flow meter 18 collect the temperature, pressure, and flow parameters at the return liquid end in real time, all of which are transmitted to the PLC controller.

[0061] The PLC controller calculates the actual heat dissipation power of the liquid-cooled load in real time based on the supply and return liquid temperature difference and the supply liquid flow rate, according to the formula Q=cmΔT (where Q is the heat dissipation power, c is the specific heat capacity of the cooling medium, m is the mass flow rate, and ΔT is the supply and return liquid temperature difference). The PLC controller compares the actual heat dissipation power with the target power value and dynamically adjusts the opening of the second electric regulating valve 19 using a PID control algorithm: when the actual heat dissipation power is lower than the target power, the opening of the second electric regulating valve 19 is increased, increasing the coolant flow rate; when the actual heat dissipation power is higher than the target power, the opening of the second electric regulating valve 19 is decreased, reducing the coolant flow rate. Through continuous closed-loop adjustment, the actual heat dissipation power is stabilized near the target power value, with a deviation not exceeding ±2%.

[0062] The forced air-cooled fan automatically starts after the air-cooled load resistive element is energized, drawing in outside cold air into the air duct. The air flows over the surface of the air-cooled load resistive element, carrying away heat before being discharged, ensuring that the temperature rise at the air outlet of the air-cooled load is controlled within 30K.

[0063] (iv) Power regulation During operation, operators can modify the target power value at any time on the touchscreen human-machine interface 4. For example, if the target power is adjusted from 60kW to 45kW, the PLC controller will recalculate the number of load levels to be engaged based on the new target power value, which is 15 levels. It will then control the branch load contactor group 24 to disconnect 5 branch contactors (i.e., disconnect the 15kW load), and simultaneously reduce the opening of the second electric regulating valve 19 to decrease the coolant flow, thus matching the heat dissipation power with the new load power. The power adjustment process is smooth and responsive, with an adjustment time of no more than 5 seconds.

[0064] (v) System shutdown The operator clicks the "Stop Unloading" button on the touchscreen HMI 4, or rotates the rotary switch 5 to the "Stop" position. The PLC controller controls all branch contactors of the branch load contactor group 24 to disconnect, cutting off all loads; simultaneously, it controls the second electric regulating valve 19 to close, stopping the coolant supply; the forced air-cooled fan continues to run for 30 seconds before automatically stopping to fully dissipate the residual heat from the air-cooled load resistive elements. The equipment enters the shutdown state.

[0065] (vi) Fault Protection During operation, the PLC controller will immediately activate its protection program if any of the following abnormal conditions occur: When the supply temperature sensor 13 or the return temperature sensor 16 detects that the temperature of the cooling medium exceeds the set threshold (e.g., 60°C), the PLC controller determines that it is an over-temperature fault, issues an audible and visual alarm, and simultaneously controls the three-phase main contactor 23 to disconnect, cutting off the load power supply.

[0066] When the liquid supply pressure sensor 14 detects that the liquid supply pressure is lower than the set threshold (e.g., 0.2 MPa), the PLC controller determines that it is an undervoltage fault, issues an alarm, and cuts off the load power supply.

[0067] When the differential pressure sensor detects that the pressure difference between the supply and return fluids exceeds the set threshold (e.g., 0.5 MPa), the PLC controller determines that there is a pipeline blockage fault, issues an alarm, and cuts off the load power supply.

[0068] When the three-phase leakage current protector 26 operates, the PLC controller detects the leakage signal, issues an alarm, and cuts off the load power supply.

[0069] When the three-phase voltage acquisition module 27 or the current transformer detects overvoltage or overcurrent, the PLC controller judges it as an electrical fault, issues an alarm, and cuts off the load power supply.

[0070] When the liquid circuit sensor detects an abnormal flow (for example, the liquid supply flow meter 15 detects a sudden drop in flow to zero), the PLC controller determines that there is a leak or pump failure, issues an alarm, and cuts off the load power supply.

[0071] All fault information is displayed and recorded in real time on the touch screen human-machine interface 4, which facilitates maintenance personnel to quickly locate and troubleshoot faults.

[0072] (vii) Remote cluster control When multiple devices of this invention are deployed in the same data center, the PLC controllers of all devices can be connected to the same remote host computer via Ethernet. Operators install monitoring software on the remote host computer and establish communication connections with each device via the Modbus TCP communication protocol. The remote host computer can display the operating status and parameters of all devices in real time and can simultaneously issue unified power setting commands to multiple devices, achieving second-level sudden load increases. For example, in simulating a full-load test of a data center, the remote host computer can simultaneously issue an 80kW full-load command to 10 devices, and all devices will complete the load synchronously within 1 second, perfectly simulating the real full-load conditions of a data center.

[0073] The working principle of the dummy load of the integrated air-hydraulic cabinet of this invention is as follows: Power loading principle: An external three-phase AC power supply is connected to the main power control module via an industrial connector. After passing through the three-phase incoming fuses and the three-phase main contactor, the branch load contactor group distributes power to the liquid-cooled load resistor groups and air-cooled load resistor elements of each air-liquid composite load module according to the preset control logic. The PLC controller calculates the required load level combination based on the target power value set by the user through the touch screen human-machine interface or remote host computer, and controls the corresponding contactors in the branch load contactor group to close or open, realizing power level switching in 3kW increments. Since the liquid-cooled load resistor groups and air-cooled load resistor elements are purely resistive loads, they only consume active power after being connected, and the voltage and current are in phase, without generating reactive current, thus having no adverse impact on the power grid.

[0074] Liquid cooling principle: The cooling medium supplied by the external liquid cooling source enters the main supply pipe through the quick-connect chuck interface. After the flow rate is regulated by the first electric regulating valve, it enters the liquid pipelines of each air-liquid composite load module through various supply branches. The cooling medium flows through the liquid-cooled load resistor array in the liquid pipeline, absorbing the heat generated by the energized resistor elements, thus increasing its temperature. It then converges into the main return pipe through various return branches and returns to the external liquid cooling source through the quick-connect chuck interface, completing the cooling cycle. Sensor components collect the temperature, pressure, and flow rate parameters of the supplied and returned liquids in real time and feed them back to the PLC controller. The PLC controller calculates the actual heat dissipation power of the liquid-cooled load based on the real-time collected parameters and compares it with the target power value. Using a PID control algorithm, it dynamically adjusts the opening of the second electric regulating valve to achieve precise regulation of the coolant flow rate, dynamically matching the actual heat dissipation power with the load power.

[0075] Air-cooling principle: After the air-cooled load resistor element heats up when energized, the forced air-cooling fan starts running, drawing outside cold air into the air duct of the module housing. The air flows over the surface of the air-cooled load resistor element, carrying away heat, and is then discharged from the outlet, achieving forced air-cooling of the load. The expulsion of hot air from the air duct creates a negative pressure inside the module housing, continuously drawing in outside cold air and forming a continuous air-cooling cycle.

[0076] Control and Protection Principles: The PLC controller, as the core control unit, receives local operation commands from the user via a touchscreen HMI or control commands from a remote host computer via a remote communication interface, enabling comprehensive control of the equipment. The PLC controller collects voltage signals from the three-phase voltage acquisition module, three-phase current signals (acquired through current transformers), sensor component signals from the hydraulic control module, and temperature signals from each air-hydraulic composite load module in real time, providing comprehensive monitoring of the equipment's operating status. When abnormal conditions such as overcurrent, overtemperature, leakage, or short circuit are detected, the PLC controller immediately issues an alarm signal and displays fault information on the touchscreen HMI. Simultaneously, it controls the three-phase main contactor to disconnect, cutting off the load power supply and providing multiple safety protections.

[0077] Cluster control principle: Multiple devices of this invention can be networked through a remote communication interface. The remote host computer interacts with the PLC controller of each device through the Modbus TCP communication protocol to realize the synchronous switching of multiple devices, unified parameter setting and centralized monitoring of operating status. The sudden loading operation is completed in seconds, which meets the clustered and large-scale testing needs of large data centers and power systems.

[0078] Example 2 The difference between this embodiment and Embodiment 1 is that the number of air-liquid composite load modules 2 is six. The total power of the liquid-cooled load units is 60kW (10kW per unit), the total power of the air-cooled load units is 20kW (approximately 3.33kW per unit), and the total power of the equipment is 53.3kW. The six air-liquid composite load modules 2 are stacked in the middle area of ​​the cabinet. This embodiment is suitable for load testing requirements of 50kW-level liquid cooling systems. Power adjustment is in 3kW increments, supporting continuous adjustment from 3kW to 53kW.

[0079] The other structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0080] Example 3 The difference between this embodiment and Embodiment 1 is that the liquid-cooled load resistor group 25 of the liquid-cooled load unit is composed of multiple alloy tubular resistor elements connected in series, rather than in parallel. The series configuration is suitable for test conditions with higher voltage and lower current. Each resistor element bears the same current, and the total resistance value is the sum of the resistance values ​​of each element. The series-configured liquid-cooled load resistor group 25 is also encapsulated in a stainless steel sealed housing and immersed in the cooling medium of the liquid pipeline.

[0081] The other structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0082] Example 4 The difference between this embodiment and Embodiment 1 is that the forced air cooling fan uses a centrifugal fan instead of an axial fan. The centrifugal fan is located at the air outlet of the duct and uses centrifugal force to extract the hot air in the duct and discharge it radially. It is suitable for occasions with high duct resistance and has the advantages of high air pressure and low noise.

[0083] The other structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0084] Example 5 The difference between this embodiment and Embodiment 1 is that the PLC controller uses a domestically produced brand, such as Inovance Technology or Hollysys series PLCs, instead of the Siemens S7-1200 series. Domestically produced PLCs also possess powerful logic control capabilities, analog signal processing capabilities, and PID control functions, and support Modbus TCP and RS485 communication protocols, fully meeting the control requirements of this invention.

[0085] The other structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0086] Example 6 The difference between this embodiment and Embodiment 1 is that the remote communication interface uses a wireless communication module (such as a 4G / 5G module or a Wi-Fi module) instead of a wired Ethernet communication interface. The wireless communication module frees the device from the limitations of network cable cabling, making it more flexible and convenient for temporary deployments in data center server rooms and mobile testing scenarios. The wireless communication module also supports the Modbus TCP communication protocol for data interaction with a remote host computer.

[0087] The other structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0088] Description of alternative solutions In addition to the above embodiments, the technical solution of the present invention can also have the following alternative solutions: Alternative Solution 1: Split-type non-integrated design. The liquid-cooled load unit, electrical control module, and liquid control module are deployed separately in independent cabinets, eliminating the need for an integrated cabinet design. System setup is achieved through temporary on-site wiring and piping. While this alternative reduces the manufacturing difficulty and transportation costs of a single cabinet, the on-site installation process is complex, deployment efficiency is low, and the footprint is large. Furthermore, the liquid piping uses on-site welding or threaded connections instead of quick-connect clamp interfaces, making it prone to leaks and airlocks. The system stability and reliability are lower than the integrated solution of this invention.

[0089] Alternative Solution 2: Single-channel monitoring design. This solution eliminates the temperature, pressure, and flow sensors at the return end, implementing single-channel monitoring only at the supply end. It also eliminates the closed-loop control of the second electric regulating valve, replacing it with a manual ball valve. While this solution significantly reduces manufacturing costs and system complexity, it cannot accurately calculate actual heat dissipation power, nor can it achieve automatic adjustment of coolant flow rate and precise control of power gradients. Both operating condition monitoring accuracy and power regulation accuracy are significantly reduced.

[0090] Alternative Solution 3: Fixed-Power Switching Design. This solution eliminates the tiered contactor group and refined step switching design, using only three fixed power switching levels (e.g., 20kW / 40kW / 80kW). While this simplifies the electrical control system and reduces costs, it lacks refined power regulation, cannot adapt to low-power, multi-level testing conditions, and its application scenarios are limited.

[0091] Alternative Solution 4: Single Liquid-Cooled Architecture Design. This solution eliminates the air-cooled load unit, retaining only the liquid-cooled load unit. The device can only simulate the liquid-cooled heat dissipation of a liquid-cooled server, not the air-cooled portion. While this alternative is simpler and cheaper, it cannot accurately reproduce the actual operating conditions of a server with coordinated "liquid cooling + air cooling," resulting in insufficient realism and accuracy in the test results.

[0092] While the above alternatives may be feasible in certain application scenarios, their technical effects are all inferior to the integrated, dual-path monitoring closed-loop control, refined step-by-step switching, and air-liquid composite architecture of the present invention.

[0093] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described and explained in the present invention, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A dummy load for a fan-hydraulic integrated cabinet, characterized in that, Includes a cabinet and an electrical control module, at least one set of air-liquid composite load module and liquid control module integrated within the cabinet; The electrical control module, the air-liquid composite load module, and the liquid control module are stacked sequentially along the height of the cabinet, and the modules are detachably connected through standardized electrical interfaces and liquid quick-connect interfaces. The electrical control module is based on a PLC controller and integrates a touch screen human-machine interface and a remote communication interface. It is electrically connected to each of the wind-liquid composite load modules through the standardized electrical interface. The liquid control module integrates a liquid supply main pipe, a liquid return main pipe, a first electric regulating valve installed on the liquid supply main pipe, and sensor components installed on the liquid supply main pipe and the liquid return main pipe. It is connected to the liquid circuit of each of the air-liquid composite load modules through the liquid circuit quick-connect interface. Each of the air-liquid composite load modules includes a liquid-cooled load unit and an air-cooled load unit. The liquid-cooled load unit includes a liquid-cooled load resistor group and liquid pipelines, and the air-cooled load unit includes an air-cooled load resistor element and a forced air-cooled fan.

2. The dummy load of the integrated air-hydraulic cabinet according to claim 1, characterized in that, The main electrical control module also includes a three-phase incoming fuse, a three-phase main contactor, a branch load contactor group, a three-phase leakage current protection device, and a three-phase voltage acquisition module; The input terminal of the three-phase incoming fuse is connected to an external three-phase AC power supply via an industrial connector. The output terminal of the three-phase incoming fuse is connected to the input terminal of the three-phase main contactor. The output terminal of the three-phase main contactor is connected to the input terminal of the branch load contactor group and the input terminal of the three-phase leakage current protector, respectively. Each output terminal of the branch load contactor group is connected to the liquid-cooled load resistor group and the air-cooled load resistor element of each of the air-liquid composite load modules, respectively. The output terminal of the three-phase leakage current protector is connected to the three-phase voltage acquisition module. The three-phase leakage current protector also transmits its detection signal to the PLC controller. The PLC controller is connected to the touch screen human-machine interface, the three-phase main contactor, the branch load contactor group, the three-phase leakage current protector, the three-phase voltage acquisition module, and the first electric regulating valve and the sensor assembly of the hydraulic total control module.

3. The dummy load of the integrated air-hydraulic cabinet according to claim 1, characterized in that, The shunt load contactor group includes multiple shunt contactors, each of which controls the on / off state of the liquid-cooled load resistor group and the air-cooled load resistor element of a group of the air-liquid composite load modules. The PLC controller controls the corresponding number of branch contactors to close or open according to the set target power value, so as to realize the power level switching with a minimum step of 3kW, and the power adjustment range is continuously adjustable from 3kW to 80kW.

4. The dummy load of the integrated air-hydraulic cabinet according to claim 1, characterized in that, The main supply pipe of the liquid control module is equipped with a second electric regulating valve, a liquid supply temperature sensor, a liquid supply pressure sensor and a liquid supply flow meter, and the return liquid main pipe is equipped with a return liquid temperature sensor, a return liquid pressure sensor and a return liquid flow meter. The main supply pipe and the main return pipe are respectively provided with quick-connect chuck interfaces for quick connection to an external liquid cooling source; The main liquid supply pipe is connected to the inlet end of the liquid pipeline of each of the air-liquid composite load modules through the liquid supply branch pipes, and the main return liquid pipe is connected to the outlet end of the liquid pipeline of each of the air-liquid composite load modules through the return liquid branch pipes.

5. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, The PLC controller calculates the actual heat dissipation power of the liquid-cooled load based on the parameters collected in real time by the liquid supply temperature sensor, the liquid supply pressure sensor, the liquid supply flow meter, the return liquid temperature sensor, the return liquid pressure sensor, and the return liquid flow meter. It then compares the actual heat dissipation power with the target power value and dynamically adjusts the opening of the second electric regulating valve through a PID control algorithm to dynamically match the actual heat dissipation power with the load power.

6. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, Each of the air-liquid composite load modules also includes a module housing, with the liquid-cooled load unit disposed in the lower region of the module housing and the air-cooled load unit disposed in the upper region of the module housing; The liquid-cooled load resistor group is composed of multiple alloy tubular resistor elements connected in parallel or in series. Each alloy tubular resistor element is encapsulated in a sealed housing, which is immersed in the cooling medium of the liquid pipeline. The liquid pipeline is made of stainless steel and the inner wall is passivated for corrosion protection. The inlet and outlet ends of the liquid pipeline are respectively equipped with quick-connect chuck interfaces. The air-cooled load resistor element is made of nickel-chromium alloy resistance wire and is fixedly installed on an insulating bracket. It is located in the air duct of the module housing, and the forced air-cooling fan is located at the air outlet of the air duct.

7. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, The remote communication interface includes an Ethernet communication interface and an RS485 communication interface. The Ethernet communication interface supports the Modbus TCP communication protocol, and the RS485 communication interface supports the Modbus RTU communication protocol.

8. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, The main control module is equipped with a rotary switch and an emergency stop switch on its panel. The rotary switch is connected to the PLC controller for signal control of the equipment, and is used to start, stop and switch modes. The emergency stop switch is connected in series in the control circuit of the three-phase main contactor and is used to cut off the load power supply in an emergency.

9. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, Both the liquid-cooled load resistor group and the air-cooled load resistor element are purely resistive loads.

10. A dummy load for a fan-hydraulic integrated cabinet according to claim 1, characterized in that, The supply main pipe and the return main pipe are respectively equipped with butterfly valves. The butterfly valves are located at the end of the supply main pipe and the return main pipe near the quick-release chuck interface, and are used to cut off the liquid circuit during maintenance. The air-cooled load unit also includes an air duct temperature sensor installed in the air duct for real-time monitoring of the operating temperature of the air-cooled load.

Images