Self-adaptive temperature control system and method for hydrogen-cooled generator set based on metal hydrogen storage

Abstract

A self-adaptive temperature control system and method for a hydrogen-cooled generator set based on metal hydrogen storage belongs to the technical field of hydrogen-cooled generator sets and comprises a hydrogen-cooled generator set body, a metal hydrogen storage device, an outer circulation pipeline and a heat dissipation device. The outer circulation pipeline is respectively connected with the hydrogen-cooled generator set body and the metal hydrogen storage device to form a closed-loop circulation loop; the metal hydrogen storage device utilizes the characteristics of high-temperature hydrogen desorption and low-temperature hydrogen absorption and is matched with the heat dissipation device to achieve dynamic adjustment of the hydrogen circulation amount, and then self-adaptive temperature control is conducted on the hydrogen-cooled generator set body. A hydrogen production machine and a high-pressure hydrogen storage tank are omitted, the working pressure of the metal hydrogen storage device is smaller than 3 MPa, and the metal hydrogen storage device belongs to a medium-pressure container and has no high-pressure explosion risk; the device can move flexibly, a special safety isolation distance is not needed, hydrogen is only circulated in a closed loop, and the leakage risk is extremely low; a special operation license is not needed in the maintenance process, and the manual operation risk is reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of hydrogen-cooled generator sets, specifically referring to an adaptive temperature control system and method for hydrogen-cooled generator sets based on metal hydrogen storage. Background Technology

[0002] Hydrogen-cooled generator sets are widely used in large generator sets due to the extremely high thermal conductivity of hydrogen, which results in superior cooling efficiency compared to traditional cooling media. Existing hydrogen-cooled generator set cooling systems generally employ a "hydrogen generator + high-pressure hydrogen storage tank + internal circulation cooling" architecture. The specific working principle is as follows: after hydrogen is produced by the hydrogen generator, it is stored in a high-pressure hydrogen storage tank. Then, the high-pressure hydrogen is injected into the generator set through a pressure reduction device. Fans at both ends of the generator set drive the hydrogen to form an internal circulation within the unit. The hot hydrogen flows through the cooling devices at the four corners of the unit, dissipating heat and thus cooling the generator set.

[0003] However, existing technologies have the following significant drawbacks: Significant safety hazards and high maintenance costs: Hydrogen generators and high-pressure hydrogen storage tanks need to be installed near the generator set for a long time. The working pressure of the high-pressure hydrogen storage tank usually far exceeds 10MPa, which is a high-pressure dangerous container that is prone to leakage, explosion and other safety accidents. At the same time, the operation and maintenance of the hydrogen generator and the regular inspection of the high-pressure hydrogen storage tank both require professional personnel and special operation qualifications, resulting in high long-term maintenance costs.

[0004] Hydrogen resources are wasted in large quantities: When generator sets are shut down for a long time, in order to reduce the risk of gas leakage and mechanical fatigue of seals, the high-pressure hydrogen in the unit needs to be replaced by inert gas or directly discharged to a safe pressure. During the replacement process, hydrogen cannot be recovered, and direct discharge results in a complete waste of resources. When the unit is maintained, the internal hydrogen must be vented and replaced with inert gas, which further aggravates the waste of hydrogen.

[0005] Temperature control response is lagging and poses safety risks: When the unit is running, the amount of hydrogen inside is fixed. When the load changes and the heat dissipation increases, the existing technology can either increase the cooling capacity of the cooling device to dissipate heat, but the cooling capacity adjustment has a significant lag and cannot quickly match the heat dissipation demand; or add hydrogen to the unit through a high-pressure hydrogen storage tank to increase the circulation of the cooling medium. However, frequent hydrogen filling and releasing not only wastes hydrogen, but also increases the risk of leakage due to frequent pressure fluctuations, further amplifying safety hazards.

[0006] The system has a complex structure and poor environmental adaptability: traditional systems need to be equipped with multiple independent modules such as hydrogen production, hydrogen storage, pressure reduction, and internal circulation cooling, resulting in a cumbersome overall structure and a large space occupation; high-pressure hydrogen storage tanks require a dedicated safety isolation area, are inconvenient to move, and have strict requirements on the site conditions and safety distances of the placement environment, thus limiting their environmental adaptability. Summary of the Invention

[0007] This invention aims to solve the problems of high safety hazards, serious hydrogen waste, slow temperature control response, and complex structure in existing hydrogen-cooled generator cooling systems, and specifically achieves the following objectives: By replacing the traditional hydrogen production machine + high-pressure hydrogen storage tank hydrogen supply mode with solid-state hydrogen storage, the safety hazards caused by high-pressure hydrogen storage are eliminated and maintenance costs are reduced. By utilizing the physical properties of metal hydrogen storage materials that release hydrogen at high temperatures and absorb hydrogen at low temperatures, hydrogen can be recovered and stored during shutdowns and maintenance, thus avoiding hydrogen waste. Based on the dynamic hydrogen absorption and desorption characteristics of metal hydrogen storage, the hydrogen circulation volume can be adaptively adjusted to quickly respond to the heat dissipation demand caused by changes in unit load and improve the temperature control response rate. The overall structure of the hydrogen-cooled generator set is simplified, improving the system's environmental adaptability and ease of movement.

[0008] According to the technical solution of the present invention, an adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage is provided, and the specific technical solution is as follows: (I) Overall System Structure This system includes a hydrogen-cooled generator set, a metal hydrogen storage device, an external circulation pipeline, an external heat dissipation device, and sealing connections. The connection relationships and structural features of each component are as follows: Hydrogen-cooled generator set body: The core power generation components of the existing hydrogen-cooled generator set are retained, but the internal corner cooling devices and the fans that drive the internal circulation at both ends are removed. Hydrogen inlet and outlet interfaces that match the external circulation pipeline are reserved, and sealing gaskets are installed at the interfaces to ensure the airtightness of the hydrogen circulation.

[0009] Metal hydrogen storage device: It has a medium-pressure vessel structure with an operating pressure of <3MPa. The interior is filled with metal hydrogen storage materials (such as LaNi5 series, TiFe series, and other solid hydrogen storage alloys). The device shell is made of hydrogen corrosion resistant metal materials (such as 304 stainless steel). The shell has an external mounting surface that matches the heat dissipation device, and an internal hydrogen flow channel that is connected to the external circulation pipeline to ensure that the hydrogen can fully contact the metal hydrogen storage material. The bottom of the device is equipped with casters, which can be flexibly adjusted according to installation requirements without the need for a dedicated safety isolation area.

[0010] External circulation pipeline: Hydrogen-resistant and corrosion-resistant metal pipeline (such as seamless stainless steel pipe) is used. Both ends are connected to the hydrogen inlet and outlet of the hydrogen-cooled generator set and the hydrogen flow channel interface of the metal hydrogen storage device through sealed flanges, forming a closed-loop circulation loop of "generator set body → metal hydrogen storage device → heat dissipation device → generator set body"; pressure monitoring sensors are installed on the pipeline to monitor the hydrogen pressure in the circulation loop in real time.

[0011] External heat dissipation device: It is installed on the outside of the metal hydrogen storage device and adopts an air-cooled heat sink assembly or a water-cooled heat dissipation coil structure. The heat dissipation power can be adjusted by the temperature control module. The function of the heat dissipation device includes two aspects: first, to cool down the hot hydrogen in the circulation loop; second, to intervene in the hydrogen absorption / desorption rate by regulating the shell temperature of the metal hydrogen storage device.

[0012] Sealing components: All pipe interfaces and flange connections use hydrogen-sealing special sealing components (such as PTFE reinforced gaskets) to ensure the airtightness of the circulation loop and prevent hydrogen leakage.

[0013] (II) Working principle and temperature control mechanism The core of this system lies in utilizing the physical properties of metallic hydrogen storage materials—high-temperature hydrogen release and low-temperature hydrogen absorption—combined with an external circulation architecture to achieve adaptive temperature control. The specific operating process is divided into three modes: Unit operating conditions: After the hydrogen-cooled generator set starts, the internal power generation components generate heat, which raises the temperature of the hydrogen in the circulation loop; the hot hydrogen flows into the metal hydrogen storage device through the external circulation pipeline and exchanges heat with the internal metal hydrogen storage material. The metal hydrogen storage material releases the stored hydrogen after being heated, which adaptively increases the amount of hydrogen circulating in the closed loop. When the incremental hot hydrogen gas flows through the heat dissipation device outside the metal hydrogen storage device, it is rapidly cooled down. The cooled hydrogen gas then flows back to the generator set body through the external circulation pipeline to complete the heat dissipation. When the unit load increases and the heat dissipation increases, the temperature of the circulating hydrogen rises synchronously, the hydrogen release rate of the metal hydrogen storage material accelerates, the hydrogen circulation volume further increases, and the temperature control module automatically increases the heat dissipation power of the heat dissipation device to achieve rapid response to heat dissipation demand. When the unit load decreases and the heat dissipation decreases, the temperature of the circulating hydrogen decreases, the hydrogen release rate of the metal hydrogen storage material slows down, some hydrogen is reabsorbed, the circulation volume decreases adaptively, and the power of the heat dissipation device decreases synchronously to maintain the unit temperature stability.

[0014] Unit shutdown condition: After the hydrogen-cooled generator unit stops running, no more heat is generated inside, the temperature of the circulating hydrogen gradually decreases, and the shell temperature of the metal hydrogen storage device decreases simultaneously; the metal hydrogen storage material starts the hydrogen absorption process in the low temperature environment, gradually absorbing and solidifying the hydrogen in the generator unit through the external circulation pipeline, so that the hydrogen pressure in the unit continues to decrease until it drops to the safe pressure range of 0.1-0.3MPa, effectively reducing the risk of gas leakage and mechanical fatigue of seals under shutdown conditions.

[0015] Unit maintenance conditions: When the generator unit needs to be maintained, there is no need to perform inert gas replacement. You only need to wait for the metal hydrogen storage device to complete the absorption of hydrogen in the unit. Once the pressure in the unit is confirmed to have dropped to a safe value by the pressure monitoring sensor, maintenance work can be carried out directly. After maintenance, the metal hydrogen storage device is slightly heated to 50-80℃ using an external heating device. The stored hydrogen is released from the metal hydrogen storage material and refilled into the circulation loop, allowing the unit to start operation.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention eliminates the need for a hydrogen generator and a high-pressure hydrogen storage tank. The working pressure of the metal hydrogen storage device is <3MPa, classifying it as a medium-pressure vessel with no risk of high-pressure explosion. The device is highly mobile, requiring no dedicated safety isolation distance, and the hydrogen circulates only within a closed loop, resulting in an extremely low risk of leakage. Maintenance does not require a special operation permit, reducing the risk of human error.

[0017] During shutdown and maintenance, the hydrogen in the unit is completely absorbed and stored by the metal hydrogen storage device, and can be recycled later. This completely avoids the resource waste caused by hydrogen venting or inert gas replacement in the prior art, and significantly reduces the cost of hydrogen use.

[0018] Based on the thermal-hydrogen coupling characteristics of metal hydrogen storage materials, the hydrogen circulation volume is dynamically adjusted in real time according to the heat dissipation of the generator set without manual intervention. With the power adjustment of the external heat dissipation device, the temperature control response time is significantly shortened compared with the prior art, which can quickly match the load changes of the generator set and ensure the stable operation of the generator set.

[0019] The metal hydrogen storage device of this invention has no special requirements for the placement environment and can be installed and deployed like ordinary equipment, making it easy to move. The closed-loop circulation architecture reduces dependence on the external environment and is suitable for power plants in different regions and with different site conditions. Attached Figure Description

[0020] Figure 1 shows the internal structure of an existing hydrogen-cooled generator set; Figure 2 This is a structural diagram of a solid-state hydrogen storage-hydrogen-cooled generator set according to an embodiment of the present invention; Figure 3 This is a structural diagram of the solid hydrogen storage device according to an embodiment of the present invention.

[0021] In the diagram, 1-generator set, 2-circulating fan, 3-internal cooling device, 4-high-pressure hydrogen storage tank, 5-hydrogen generator, 7-internal circulation channel; 10 - Hydrogen-cooled generator set body; 20 - Metal hydrogen storage device; 30 - External circulation pipeline; 40 - Cooling device; 21- Metal hydrogen storage device shell, 22- Metal hydrogen storage material filling cavity, 23- Hydrogen circulation channel, 24- Cooling channel, 25- Hydrogen return port, 26- Hydrogen outlet. Detailed Implementation

[0022] The technical solutions in the embodiments will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection.

[0023] like Figure 1 As shown, in the prior art, the high-pressure hydrogen storage tank 4 is connected to the generator set 1 through a pressure reducing device, and the circulating fan 2 drives the hydrogen to flow in the internal circulation channel 7. The hot hydrogen is cooled by the internal cooling device 3. The hydrogen generator 5 is connected to the high-pressure hydrogen storage tank 4 to continuously replenish the hydrogen.

[0024] like Figure 2 As shown, the present invention provides an adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage. The system eliminates the hydrogen generator and high-pressure hydrogen storage tank. The hydrogen-cooled generator set body 10 is connected to the metal hydrogen storage device 20 through an external circulation pipeline 30. An external heat dissipation device 40 is installed on the outside of the metal hydrogen storage device 20 housing. The pipeline is sealed by a sealing flange, and the pressure monitoring sensor monitors the pressure in real time, which facilitates the movement of the metal hydrogen storage device.

[0025] Figure 3 In the middle, the metal hydrogen storage device housing 21 has a metal hydrogen storage material filling cavity 22 inside, and a hydrogen circulation channel 23 runs through the filling cavity to ensure that the hydrogen and the hydrogen storage material are in full contact; the cooling channel 24 is used to fix the external heat dissipation device, and the hydrogen return port 25 and the hydrogen outlet port 26 are connected to the external circulation pipeline.

[0026] Example 1 This embodiment provides an adaptive temperature control system for a 300MW hydrogen-cooled generator set. The specific parameters and assembly methods of each component are as follows: Hydrogen-cooled generator set body: adopts a 300MW-class hydrogen-cooled generator, eliminating the original internal cooling device and fans at both ends, and opening hydrogen inlet and outlet with a diameter of 150mm at both ends of the generator casing, respectively, and machining sealing grooves at the interface and embedding polytetrafluoroethylene reinforced sealing gaskets.

[0027] Metal hydrogen storage device: The shell is made of 304 stainless steel, with a volume of 5m³. 3 The working pressure is designed to be 2.5 MPa; the internal filling material is LaNi5-based metallic hydrogen storage material with a filling volume of 300 kg and a hydrogen storage capacity of 150 Nm³. 3 The exterior of the casing is equipped with a heat dissipation device mounting surface (with an area of ​​8m²). 2 The internal hydrogen flow channels adopt a honeycomb structure to ensure that the contact area between hydrogen and the hydrogen storage material is ≥10m². 2 .

[0028] External circulation pipeline: A seamless stainless steel pipe with a diameter of 150mm and a wall thickness of 8mm is used. The total length of the pipeline is 15m. It is connected to the generator set body interface and the hydrogen inlet and outlet interfaces of the metal hydrogen storage device through sealing flanges. The flange bolt torque is 50N.m to ensure airtightness. A pressure monitoring sensor with an accuracy of ±0.01MPa is installed on the pipeline, and the data is transmitted to the temperature control module in real time.

[0029] External heat dissipation device: Uses an air-cooled heat sink assembly; the heat sink material is aluminum alloy; the total heat dissipation area is 20m². 2 It is equipped with a 1.5kW cooling fan, and the fan speed can be adjusted within the range of 500-2000r / min via the temperature control module; the heat sink assembly is fixed to the heat dissipation mounting surface of the metal hydrogen storage device by bolts, with a fitting gap of ≤0.5mm.

[0030] Assembly requirements: After all components are assembled, the closed-loop circuit shall be tested for air tightness by pressurizing with nitrogen to 3MPa and holding the pressure for 24 hours. The pressure drop shall be ≤0.05MPa to be considered qualified. The distance between the metal hydrogen storage device and the generator set body shall be ≥1.5m, and no dedicated safety isolation area is required.

[0031] Example 2 Start-up phase: The metal hydrogen storage device is preheated by an external heating device to 60°C. The metal hydrogen storage material releases hydrogen, causing the hydrogen pressure in the closed loop to rise to 0.8MPa. The hydrogen-cooled generator set is started, and the internal power generation components begin to generate heat, gradually increasing the temperature of the circulating hydrogen to 80°C.

[0032] During the stable operation phase: the circulating hydrogen temperature is maintained at 80-90℃, the metal hydrogen storage material stably releases hydrogen, and the hydrogen circulation rate is maintained at 50 Nm³. 3 / h; The fan speed of the external heat dissipation device is set to 1200r / min to cool the hydrogen to 40-50℃ and then return it to the unit, so that the temperature of the unit casing is stable below 60℃.

[0033] During the load surge phase: when the unit load increases from 300MW to 350MW, the heat dissipation increases by 30%, and the circulating hydrogen temperature rises to 110℃ within 5 minutes; the hydrogen release rate of the metal hydrogen storage material accelerates, and the hydrogen circulation volume increases to 70Nm³. 3 / h, and at the same time, the temperature control module automatically increases the speed of the cooling fan to 1800r / min, the hydrogen temperature drops to 55℃, and the unit temperature recovers to a stable state within 10 minutes without overheating.

[0034] Shutdown Phase: After the unit stops operating, the temperature of the circulating hydrogen gradually decreases, reaching ambient temperature (25℃) within 2 hours; the metal hydrogen storage material starts absorbing hydrogen, and the pressure in the circuit drops from 0.8MPa to 0.2MPa; maintaining the shutdown state for 24 hours, there is no significant pressure increase, and the leakage is ≤0.001Nm. 3 / h.

[0035] Maintenance phase: 4 hours after shutdown, when the pressure in the circuit drops to 0.15MPa, disconnect the external circulation pipeline from the generator set's connecting flange and directly inspect the internal components of the unit; after maintenance, reconnect the pipeline, preheat the metal hydrogen storage device to 50℃, release hydrogen to restore the circuit pressure to 0.8MPa, and the unit can be restarted.

[0036] Example 3 The system of this invention was compared with an existing conventional system on a 300MW hydrogen-cooled generator set. The test results are shown in Table 1 below: Table 1 Test results show that the system of the present invention is significantly superior to the prior art in terms of hydrogen utilization rate, temperature control response speed, cost control and safety.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage, characterized in that, Includes the hydrogen-cooled generator set body, metal hydrogen storage device, external circulation pipeline and heat dissipation device; The external circulation pipeline is connected to the hydrogen-cooled generator set body and the metal hydrogen storage device respectively, forming a closed-loop circulation circuit. The metal hydrogen storage device utilizes the characteristics of high-temperature hydrogen release and low-temperature hydrogen absorption, and in conjunction with a heat dissipation device, achieves dynamic adjustment of the hydrogen circulation volume, thereby enabling adaptive temperature control of the hydrogen-cooled generator set.

2. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, The hydrogen storage device has a hydrogen storage pressure of <3 MPa and is a medium-pressure vessel structure.

3. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, The external circulation pipeline allows the hot hydrogen gas discharged from the hydrogen-cooled generator set to first flow through the metal hydrogen storage device, and then through the heat dissipation device to complete heat exchange before flowing back to the hydrogen-cooled generator set. This flow path increases the heat exchange area and improves the heat exchange efficiency.

4. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, When the hydrogen-cooled generator set is in operation, the metal hydrogen storage device is heated by circulating hot hydrogen to release hydrogen, increasing the amount of hydrogen circulating in the closed loop to enhance the heat dissipation effect; when the hydrogen-cooled generator set is shut down or under maintenance, it absorbs the hydrogen in the closed loop through cooling and stores it solidified.

5. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, The heat dissipation device is fitted to the outside of the metal hydrogen storage device. By adjusting the heat dissipation efficiency of the heat dissipation device, the hydrogen absorption and release rates of the metal hydrogen storage device are intervened, thereby achieving precise control of the internal temperature of the hydrogen-cooled generator set.

6. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, The system does not include a hydrogen generator or a high-pressure hydrogen storage tank; instead, it utilizes a metal hydrogen storage device to store, release, and recycle hydrogen.

7. The adaptive temperature control system for a hydrogen-cooled generator set based on metal hydrogen storage according to claim 1, characterized in that, The closed-loop circulation circuit ensures that hydrogen circulates only between the hydrogen-cooled generator set and the metal hydrogen storage device, eliminating the need to release hydrogen to the outside or replace it with an inert gas.

8. A temperature control method based on the system described in any one of claims 1-7, characterized in that, Includes the following steps: (1) When the hydrogen-cooled generator set is running, the internal hot hydrogen flows into the metal hydrogen storage device through the external circulation pipeline, heats the metal hydrogen storage device to release hydrogen, and increases the amount of hydrogen circulating. (2) The incremental hydrogen gas is cooled down by heat exchanger and then flows back to the hydrogen-cooled generator set body to complete the heat dissipation. (3) When the hydrogen-cooled generator set is shut down or under maintenance, the metal hydrogen storage device is cooled and absorbs and solidifies the hydrogen inside the hydrogen-cooled generator set through the external circulation pipeline, thereby reducing the hydrogen pressure inside the unit.

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