Drainage system and method of fuel cell stack and hydrogen energy automobile
The automatic drainage system solves the insulation risk caused by the accumulation of condensate water in the fuel cell stack, and achieves the air pressure balance inside the stack, avoids the impact of returning to the factory and performance, and reduces product development costs.
Patent Information
- Application Number
- CN202411546584.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-31
- Publication Date
- 2024-12-31
AI Technical Summary
During the use of fuel cell stacks, insulation risks and short-circuit failures caused by the accumulation of condensate water, which cannot be effectively solved by the existing technology, resulting in return to the factory for repair and performance impacts.
The automatic drainage system is adopted to control the solenoid valve and the check valve through the water level sensor and pressure sensor to realize automatic drainage inside the fuel cell stack, ensure air pressure balance and avoid condensation water accumulation.
It effectively avoids insulation problems caused by condensation water accumulation of the stack, reduces the impact of return to the factory maintenance and performance, and reduces product development costs.
Smart Images
Figure CN119230879A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a drainage system and method for a fuel cell stack and a hydrogen-powered vehicle, belonging to the technical field of new energy vehicles. Background Art
[0002] The fuel cell stack is the most important component in the fuel cell system. During use, it will generate high heat and require cooling water to cool down. At the same time, due to the existence of other channels connecting the stack to the external environment, the internal temperature and humidity of the stack will also change due to the influence of ambient temperature and humidity. When the stack is running, the humidity inside the stack is as high as over 90%. When the stack is shut down, changes in the internal and external environment will cause condensed water to accumulate inside the stack, increasing the risk of internal short circuits. At the same time, the core of a high-power fuel cell stack is often assembled from hundreds of single cells. In order to ensure the sealing performance of the reaction gas inside the fuel cell, each fuel cell is equipped with a sealing system. However, during the operation of the fuel cell, a small amount of humid gas and hydrogen will still leak to the surface of the stack core through the sealing material and the sealing interface. Once condensed water accumulates between the single cells, the insulation value inside the stack will be reduced, and even the risk of short circuit and burning between the single cells in the core will be caused.
[0003] Currently, most products on the market try to reduce the hydrogen concentration and water vapor humidity inside the fuel cell stack by opening holes in the fuel cell packaging shell and optimizing the design of the air compressor purge flow distribution.
[0004] But in reality, the air compressor can only allocate a smaller flow rate to reduce the hydrogen concentration inside the fuel cell stack, otherwise it will affect the flow rate of the air compressor entering the fuel cell stack cavity entrance, which in turn affects the fuel cell stack performance. The smaller gas flow rate cannot meet the purpose of purging moisture inside the fuel cell stack. After long-term use, internal moisture leakage and condensation water caused by external environmental changes will accumulate inside the fuel cell stack. When a certain water level is reached and the accumulated water contacts the energized parts and metal parts, insulation risks will occur. This often results in insulation failures after long-term use by users after the company installs the battery. Conventional purging strategies cannot solve the problem of water accumulation. When a failure occurs, the fuel cell stack must be removed from the vehicle and returned to the fuel cell stack manufacturer for dismantling and repair. This is time-consuming and labor-intensive, causing customer complaints and economic losses. Summary of the invention
[0005] The purpose of the present invention is to provide a drainage system, method and hydrogen-powered vehicle for a fuel cell stack, which can solve the problems in the background technology, realize automatic cyclic drainage, avoid the stack from being returned to the factory for repairs due to accumulation of condensed water after loading, reduce the impact on the stack performance and test verification caused by the purge gas diverted from the air compressor, and reduce the cost in the product development process.
[0006] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.
[0007] A fuel cell stack drainage method, comprising: Get water level signal; If the water level signal is greater than the preset water level, a signal is generated to close the solenoid valve and start the air compressor to increase the pressure inside the fuel cell stack; and the pressure signal is obtained in real time; If the water level signal is less than or equal to the preset water level, the solenoid valve is kept open; If the pressure signal is greater than the preset pressure, a signal to open the one-way valve is generated for drainage. Until the water level signal is less than or equal to the preset water level, a signal to open the solenoid valve and close the one-way valve is generated to maintain the air pressure balance inside the fuel cell stack and achieve automatic drainage.
[0008] Optionally, the method for obtaining the water level signal includes: When the fuel cell stack is started, the top of the fuel cell stack is connected to the vehicle tail exhaust through the stack purge outlet, so as to release the purged hydrogen into the atmosphere through the vehicle tail exhaust; The bottom of the fuel cell stack is connected to the air compressor through the stack purge inlet to divert a portion of the air compressor flow to purge the hydrogen inside the fuel cell stack. At the same time, during the purge process, condensed water is generated inside the fuel cell stack and gathered in the water collection part, so that the water level sensor in the water collection part senses the water level signal.
[0009] Optionally, the threshold range of the preset pressure is 30-50 kPa.
[0010] Optionally, it also includes: if the pressure signal is less than or equal to a preset pressure, maintaining the solenoid valve closed until the pressure signal is greater than the preset pressure.
[0011] A fuel cell stack drainage system, comprising: A fuel cell stack, wherein one side of the fuel cell stack is provided with a stack purge inlet connected to an air compressor, and the other side of the fuel cell stack is provided with a stack purge outlet connected to a vehicle tail exhaust; A water collecting part is arranged at the lowest position of the fuel cell stack, and the water collecting part is communicated with the interior of the fuel cell stack, and is used to receive condensed water inside the fuel cell stack; The pressure sensor is installed inside the fuel cell stack to detect the internal air pressure of the fuel cell stack.
[0012] The controller executes the steps of the above method to realize automatic water collection and discharge of the water collection part.
[0013] Optionally, the water collecting part includes: a condensed water cup and a water level sensor; wherein the condensed water cup is installed at the lowest position of the fuel cell stack to receive condensed water flowing out of the fuel cell stack; The water level sensor is installed in the condensate cup to sense the liquid level in the condensate cup.
[0014] Optionally, the drainage system further includes: a one-way valve and a solenoid valve; Among them, the one-way valve is installed at the drain outlet of the condensed water cup to control the water collection or drainage of the condensed water cup; The solenoid valve is installed at the connection between the stack purge outlet and the vehicle tail exhaust, and is used to release the purged hydrogen into the atmosphere through the vehicle tail exhaust.
[0015] Optionally, the arrangement of the fuel cell stack on the vehicle includes any one of longitudinal, transverse and oblique arrangement.
[0016] Optionally, the drainage system also includes a display device for visually outputting water level signals and pressure signals to facilitate manual operation by the driver.
[0017] A hydrogen-powered vehicle comprises the drainage system mentioned above.
[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The method of the present invention can repeatedly realize automatic water discharge when the condensed water of the fuel cell stack accumulates to a specified liquid level, thereby ensuring that the fuel cell stack will not have insulation problems due to the accumulation of condensed water, while maintaining the gas pressure balance of the fuel cell stack to avoid affecting the power generation efficiency and continuous power generation time.
[0019] 2. The system structure of the present invention is streamlined. A drain port is designed on the battery stack packaging shell, and the layout position is at the lowest position during the use of the battery stack. When the condensed water inside the battery stack accumulates to a certain liquid level, the drain port can automatically drain the water, thereby avoiding the battery stack to be returned to the factory for repair due to the accumulation of condensed water after loading. The battery stack must be unloaded from the vehicle, causing huge manpower and economic losses; reducing the waiting time for customers to return the vehicle for repair; and also reducing the impact of the purge gas from the air compressor diversion on the battery stack performance and test verification, thereby reducing the cost during product development. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 Shown is a flow chart of the drainage method of the present invention; Figure 2 Shown is a schematic structural diagram of the drainage system of the present invention; Figure 3 Shown is a diagram showing an embodiment of the installation of the drainage system of the present invention.
[0021] In the figure: 1- condensate cup, 2- one-way valve, 3- water level sensor, 4- stack purge inlet, 5- stack purge outlet, 6- solenoid valve, 7- fuel cell stack. DETAILED DESCRIPTION
[0022] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention. Example
[0023] This embodiment provides a fuel cell stack drainage method, such as Figure 1 Shown include: Step 1: Get water level signal; Step 2: If the water level signal is greater than the preset water level, a signal is generated to close the solenoid valve 6 and start the air compressor to increase the pressure inside the fuel cell stack 7; and the pressure signal is obtained in real time; Step 3: If the water level signal is less than or equal to the preset water level, the solenoid valve 6 is kept open; Step 4: If the pressure signal is greater than the preset pressure, a signal is generated to open the one-way valve 2 for drainage. When the water level signal is less than or equal to the preset water level, a signal is generated to open the solenoid valve 6 and close the one-way valve 2 to balance the internal air pressure of the fuel cell stack 7 and achieve automatic drainage.
[0024] Optionally, the method for obtaining the water level signal includes: When the fuel cell stack 7 is started, the top of the fuel cell stack 7 is connected to the vehicle tail exhaust through the stack purge outlet 5, so as to release the purged hydrogen into the atmosphere through the vehicle tail exhaust; The bottom of the fuel cell stack 7 is connected to the air compressor through the stack purge inlet 4 to divert a portion of the air compressor flow for purging the hydrogen inside the fuel cell stack 7. At the same time, during the purge process, condensed water is generated inside the fuel cell stack 7 and gathered in the water collection part, so that the water level sensor 3 in the water collection part senses the water level signal.
[0025] Optionally, the threshold range of the preset pressure is 30-50 kPa.
[0026] Optionally, the method further includes: if the pressure signal is less than or equal to a preset pressure, maintaining the solenoid valve 6 closed until the pressure signal is greater than the preset pressure.
[0027] In this embodiment, when the battery stack is running, the water level in the condensed water cup 1 gradually rises and submerges the upper water level sensor 3. The controller and the driver can understand that there is water accumulation inside the battery stack and control the electromagnetic valve 6 of the battery stack purge outlet 5 to close. When the vehicle starts, the air compressor is working and fills the battery stack 7 with air. Since the electromagnetic valve 6 is closed, the pressure inside the battery stack will gradually rise. When the pressure inside the battery stack rises to 30~50kPa, the one-way valve 2 at the drainage outlet of the condensed water cup 1 opens to drain. When the water level drops below the water level sensor 3, the controller and the driver control the electromagnetic valve 6 of the battery stack purge outlet 5 to open. The gas inside the battery stack flows out from the battery stack purge outlet 5 to the tail exhaust of the vehicle, and the internal pressure of the battery stack 7 package drops rapidly to close to the atmospheric pressure, and the one-way valve 2 automatically closes. When water accumulates again in the battery stack 7 package, the automatic water discharge function of the battery stack 7 can be realized. Example
[0028] This embodiment provides a fuel cell stack drainage system, such as Figure 2 Shown include: The fuel cell stack 7 is vertically arranged on the vehicle, and the bottom of the fuel cell stack 7 is provided with a stack purge inlet 4 connected to an air compressor, and the top of the fuel cell stack 7 is provided with a stack purge outlet 5 connected to the vehicle tail exhaust; A water collecting part is arranged at the lowest position of the fuel cell stack 7, and the water collecting part is communicated with the interior of the fuel cell stack 7, and is used to receive condensed water inside the fuel cell stack; The pressure sensor is installed inside the fuel cell stack 7 and is used to detect the internal air pressure of the fuel cell stack 7 .
[0029] The controller executes the steps of the above method to realize automatic water collection and discharge of the water collection part.
[0030] Optionally, the water collecting part includes: a condensed water cup 1 and a water level sensor 3; wherein the condensed water cup 1 is installed at the lowest position of the fuel cell stack 7 to receive the condensed water flowing out of the fuel cell stack; The water level sensor 3 is installed in the condensed water cup 1 to sense the liquid level in the condensed water cup 1 .
[0031] Optionally, the drainage system further includes: a one-way valve 2 and a solenoid valve 6; Among them, the one-way valve 2 is installed at the drain outlet of the condensed water cup 1 to control the water collection or drainage of the condensed water cup 1; The solenoid valve 6 is installed at the connection between the stack purge outlet 5 and the vehicle tail exhaust, and is used to release the purged hydrogen into the atmosphere through the vehicle tail exhaust.
[0032] Optionally, the arrangement of the fuel cell stack 7 on the vehicle also includes: any one of horizontal and oblique arrangement, such as Figure 3As shown, in other arrangements, similar functions can be achieved by simply changing the shape or internal structure of the components, or by changing the drain port, model, and sensor position. Mainly, no matter the stack system is arranged longitudinally or horizontally, or tilted according to the requirements of the vehicle layout, the stack drain port should be arranged at the lowest position during use, so as to achieve the functional purpose of drainage.
[0033] Optionally, the drainage system also includes a display device for visually outputting water level signals and pressure signals to facilitate manual operation by the driver. When the condensed water inside the battery stack accumulates to a certain liquid level, the drain outlet can automatically or manually drain the water, avoiding the battery stack from being returned to the factory for repair due to the accumulation of condensed water after loading. The battery stack must be unloaded from the vehicle, causing huge manpower and economic losses. Example
[0034] This embodiment provides a hydrogen-powered vehicle, including the above-mentioned drainage system, and implementing the following steps during drainage: Step 1: Get water level signal; Step 2: If the water level signal is greater than the preset water level, a signal is generated to close the solenoid valve 6 and start the air compressor to increase the pressure inside the fuel cell stack 7; and the pressure signal is obtained in real time; Step 3: If the water level signal is less than or equal to the preset water level, the solenoid valve 6 is kept open; Step 4: If the pressure signal is greater than the preset pressure, a signal is generated to open the one-way valve 2 for drainage. When the water level signal is less than or equal to the preset water level, a signal is generated to open the solenoid valve 6 and close the one-way valve 2 to balance the internal air pressure of the fuel cell stack 7 and achieve automatic drainage.
[0035] In summary, the method of the present invention can repeatedly realize that when the condensed water of the battery stack accumulates to a specified liquid level, the water can be automatically discharged, thereby ensuring that the battery stack will not have insulation problems due to the accumulation of condensed water. Secondly, the system of the present invention is used to design a drain port on the battery stack packaging shell, and the arrangement position must be at the lowest position during the use of the battery stack. When the condensed water inside the battery stack accumulates to a certain liquid level, the drain port can automatically drain the water, avoiding the battery stack from being returned to the factory for repair due to the accumulation of condensed water after loading. The battery stack must be unloaded from the whole vehicle, causing huge manpower and economic losses. Reduce the waiting time for customers to return the whole vehicle for repair. It also reduces the impact of the purge gas of the air compressor diversion part on the performance of the battery stack and the test verification, and reduces the cost in the product development process. It should be understood by those skilled in the art that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.
[0036] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0037] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.
[0038] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.
[0039] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.
Claims
1. A fuel cell stack drainage method, characterized in that: include: Get water level signal; If the water level signal is greater than the preset water level, a signal is generated to close the solenoid valve and start the air compressor to increase the pressure inside the fuel cell stack; and the pressure signal is obtained in real time; If the water level signal is less than or equal to the preset water level, the solenoid valve is kept open; If the pressure signal is greater than the preset pressure, a signal to open the one-way valve is generated for drainage. Until the water level signal is less than or equal to the preset water level, a signal to open the solenoid valve and close the one-way valve is generated to maintain the internal air pressure balance of the fuel cell stack and achieve automatic drainage.
2. The fuel cell stack drainage method according to claim 1, characterized in that: Methods for obtaining water level signals include: When the fuel cell stack is started, the top of the fuel cell stack is connected to the vehicle tail exhaust through the stack purge outlet, so as to release the purged hydrogen into the atmosphere through the vehicle tail exhaust; The bottom of the fuel cell stack is connected to the air compressor through the stack purge inlet to divert a portion of the air compressor flow to purge the hydrogen inside the fuel cell stack. At the same time, during the purge process, condensed water is generated inside the fuel cell stack and gathered in the water collection part, so that the water level sensor in the water collection part senses the water level signal.
3. The fuel cell stack drainage method according to claim 1, characterized in that: The threshold range of the preset pressure is 30-50 kPa.
4. The fuel cell stack drainage method according to claim 1, characterized in that: Also includes: If the pressure signal is less than or equal to the preset pressure, the solenoid valve is kept closed until the pressure signal is greater than the preset pressure.
5. A fuel cell stack drainage system, characterized in that it includes: A fuel cell stack, wherein one side of the fuel cell stack is provided with a stack purge inlet connected to an air compressor, and the other side of the fuel cell stack is provided with a stack purge outlet connected to a vehicle tail exhaust; A water collecting part is arranged at the lowest position of the fuel cell stack, and the water collecting part is communicated with the interior of the fuel cell stack, and is used to receive condensed water inside the fuel cell stack; A pressure sensor, installed inside the fuel cell stack, for detecting the internal air pressure of the fuel cell stack; A controller for executing the steps of the method according to claim 1.
6. The fuel cell stack drainage system according to claim 5, characterized in that: The water collecting part includes: a condensed water cup and a water level sensor; wherein the condensed water cup is installed at the lowest position of the fuel cell stack to receive the condensed water flowing out of the fuel cell stack; The water level sensor is installed in the condensate cup to sense the liquid level in the condensate cup.
7. The fuel cell stack drainage system according to claim 5, characterized in that: The drainage system also includes: a one-way valve and a solenoid valve; Among them, the one-way valve is installed at the drain outlet of the condensed water cup to control the water collection or drainage of the condensed water cup; The solenoid valve is installed at the connection between the stack purge outlet and the vehicle tail exhaust, and is used to release the purged hydrogen into the atmosphere through the vehicle tail exhaust.
8. The fuel cell stack drainage system according to claim 5, characterized in that: The arrangement of the fuel cell stack on the vehicle includes any one of longitudinal arrangement, transverse arrangement and oblique arrangement.
9. The fuel cell stack drainage system according to claim 5, characterized in that: The drainage system also includes a display device for visually outputting water level signals and pressure signals.
10. A hydrogen-powered vehicle, characterized in that: Includes the drainage system described in claim 5.