Normal pressure detection device and method for hydrogen fuel stack fuel leakage

Abstract

This invention belongs to the field of fuel cell technology and discloses an atmospheric pressure detection device and method for hydrogen fuel cell stack fuel leakage. The device's partition divides the main test chamber into a main test chamber space and a circulating air duct space. A test object placement platform is located in the center of the main test chamber space near the bottom, and a wind direction and wind speed detector is installed in the space above the test object. The two ends of the main test chamber are respectively provided with a front connection and a rear connection. The end of the main test chamber space near the front connection is provided with detectors for wind speed, pressure, oxygen concentration, and temperature and humidity. The end of the main test chamber space near the rear connection is provided with a rear flow stabilizer and a hydrogen concentration detector. The circulating air duct space contains a circulating fan and a humidifying heat exchanger. The top of the circulating air duct space has a circulating air inlet and a circulating air outlet. It can be used for the detection of small hydrogen fuel cell stacks, hydrogen electric engines, and light hydrogen electric vehicles. It is also suitable for the detection of small water-cooled fuel cell stacks and their applications, and can also be used for the testing of the operational performance of hydrogen fuel cell stacks and their applications.

Description

Technical Field

[0001] The present invention belongs to the field of fuel cell technology. Specifically, it is a static and running fuel leakage normal pressure detection device and method for hydrogen fuel cell and its application, especially for small air-cooled fuel cell, hydrogen air-cooled fuel cell engine, light air-cooled hydrogen fuel cell electric vehicle, and also suitable for small water-cooled fuel cell and its application. Background Art

[0002] With the trend of carbon emission reduction, hydrogen energy technology has developed rapidly. Fuel cells can replace existing gasoline and diesel engines and generators, especially in transportation, construction, and base stations. At the same time, the leakage of its fuel hydrogen has gradually become an important detection and monitoring project and control indicator, especially the leakage and emission of hydrogen. This is based on two important reasons. One is that fuel leakage brings economic losses such as combustion hazards and reduced energy utilization, and the other is that the release of hydrogen into the atmosphere is similar to the release of carbon dioxide, which will produce a certain greenhouse effect.

[0003] In addition to certain fuel leakage during the hydrogen refueling process, there is also a certain risk of fuel leakage during fuel emissions in applications after refueling. The main leakage pathways include exhaust gas emissions of unreacted hydrogen, leakage at the seals of connectors, membrane electrode penetration, etc. The direct hazard is that the equipment itself and nearby flammable and explosion risks increase, and they accumulate in closed spaces such as indoor parking lots and tunnels, posing a risk of explosion.

[0004] Some inspection projects of hydrogen fuel cells and their applications, such as engines, small power sources, and vehicles, generally need to be carried out in an environmental chamber. Currently, there is a lack of executable and relatively clear methods for detecting hydrogen leaks.

[0005] The fresh air detection using the environmental chamber is more realistic than the partial fresh air detection, but the energy consumption of fresh air treatment is several times that of partial fresh air treatment, so it is also necessary to optimize the control device and control method of partial fresh air. When the oxygen consumption is relatively large, it is preferred to directly use untreated fresh air. Summary of the invention

[0006] In view of the above-mentioned deficiencies, the present invention provides a normal pressure detection device and method for hydrogen fuel cell fuel leakage, especially for the detection of small hydrogen fuel cell stacks, hydrogen-electric engines, and light hydrogen-electric vehicles.

[0007] The above object of the present invention is achieved through the following technical solutions:

[0008] A normal pressure detection device for hydrogen fuel cell fuel leakage, the test main cabin has a partition, the partition divides the test main cabin into two parts: the test main cabin space and the circulating air duct space, a test object placement table is provided in the center of the test main cabin space near the bottom, the test object is placed on the test object placement table, the test object is provided with a hydrogen discharge connection port, and a wind direction and wind speed detector is installed in the space above the test object; the two ends of the test main cabin are respectively provided with a front connection and a rear connection, the end of the test main cabin space near the front connection is provided with a wind speed detector, a pressure detector, an oxygen concentration detector, and a temperature and humidity detector in sequence, and the end of the test main cabin space near the rear connection is provided with a rear stabilizer plate and a hydrogen concentration detector; the circulating air duct space is provided with a circulating fan and a humidifying heat exchanger, the top of the circulating air duct space is provided with a circulating air inlet and a circulating air outlet, wherein the circulating air inlet has an inlet valve, a fresh air temperature detector, and a fresh air speed detector.

[0009] Furthermore, the test main cabin is connected and sealed with the air inlet auxiliary cabin through the front connection, and the test main cabin is connected and sealed with the air outlet auxiliary cabin through the rear connection, so that the test main cabin space and the circulating air duct space are connected to form an annular space.

[0010] Furthermore, the air inlet diversion sub-chamber has a movable bottom wheel for the air inlet diversion sub-chamber, and the air outlet diversion sub-chamber has a movable bottom wheel for the air outlet diversion sub-chamber.

[0011] Furthermore, the hydrogen discharge connection port is connected to the hydrogen discharge outlet pipe, the tail discharge buffer container, and the tail discharge buffer container outlet pipe in sequence, and a hydrogen discharge flow detector and a hydrogen discharge temperature detector are arranged in the tail discharge buffer container.

[0012] Furthermore, when hydrogen is supplied from outside, the object to be detected is provided with a raw hydrogen connection port; when hydrogen is provided by itself, the object to be detected is not provided with a raw hydrogen connection port.

[0013] Furthermore, the diversion air outlet sub-cabin is replaced by a fresh air sub-cabin, and a fresh air induced draft fan is arranged in the fresh air sub-cabin.

[0014] Furthermore, the objects to be detected include but are not limited to air-cooled fuel cells, water-cooled fuel cells, and light hydrogen electric vehicles.

[0015] Furthermore, the test object placement table includes but is not limited to a vibration table, a temperature-controlled immersion table, and a roller table for testing the operation of a light hydrogen electric vehicle.

[0016] Normal pressure detection method for hydrogen fuel cell fuel leakage: when the inlet valve and the outlet valve are fully closed, the circulating fan provides internal air flow circulation; when the inlet valve and the outlet valve are fully opened, the circulating fan provides fresh air; when the inlet valve is closed and the outlet valve is opened, or the inlet valve is opened and the outlet valve is closed, the circulation formed by the circulating fan is a mixed air formed by exhausting part of the internal air and introducing part of the fresh air;

[0017] When the detected hydrogen concentration reaches the first limit value c set by the system a 1 concentration, the inlet valve and outlet valve are opened to replace part of the fresh air to reduce the hydrogen concentration; when the detected oxygen concentration is lower than the first limit value c set by the system c When the concentration is 1, the inlet valve and outlet valve are opened to replace part of the fresh air to increase the oxygen concentration;

[0018] The anode hydrogen tail gas generated by the operation of the object being tested passes through the hydrogen exhaust connection port, then through the hydrogen exhaust pipe to reach the tail exhaust buffer container, and finally is discharged into the atmosphere or the atmospheric environment treatment system of the tail gas through the tail exhaust buffer container outlet pipe.

[0019] As a typical detection method of the present invention, specifically, the detected object battery stack is placed on the detected object placement table in the test main cabin, and the outer wall of the main cabin is detected. The hydrogen is connected to the detected object battery stack through the raw hydrogen connection port in a pipeline manner, and the gas supply pipe and the connection with the battery stack are detected for hydrogen leakage. After confirming that there is no leakage, the upper air inlet and air outlet auxiliary cabins are closed, and the circulating fan and the humidifying heat exchanger are started. The temperature and humidity detector, oxygen concentration detector, pressure detector, wind speed detector, wind direction and wind speed detector, and hydrogen concentration detector are started according to the detector data for control; then the detected object battery stack is started, and it is continuously operated, and the concentration c detected by the hydrogen concentration detector is detected. x , test chamber volume V, running time t x The leakage rate of the object being tested is: Q H =V*c x / t x , according to the set upper limit of hydrogen concentration c a 2 and c a 1, set the concentration of fresh air intake, that is, control the inlet valve and outlet valve to be partially opened. Preferably, the opening degree reaches the hydrogen concentration detector detection data obtained by continuous detection is c a 2 and c a 1 between 50% and 100% of the minimum value;

[0020] When the inlet valve and outlet valve are fully opened, if the detected hydrogen concentration still exceeds c a 2 and c a 1, an alarm is immediately sounded for inspection, and the stack is stopped from outputting electricity and supplying hydrogen to the stack, and the circulating fan is continued to be turned on to reduce the hydrogen concentration; when the oxygen concentration detected by the oxygen concentration detector is lower than the first limit value set by the system, the inlet valve and outlet valve are opened to replace part of the fresh air to increase the oxygen concentration to 20.5-21.0%;

[0021] When the control inlet valve and outlet valve are all opened, if the detected oxygen concentration is still lower than the required value for the operation of the fuel cell stack, an alarm will be sounded immediately for inspection, and at the same time, the fuel cell stack will stop outputting electricity, stop supplying hydrogen to the fuel cell stack, and continue to turn on the circulating fan to reduce the hydrogen concentration; when fresh air is introduced, the fresh air volume is calculated according to the wind speed measured by the fresh air speed detector and converted into circulating air exhaust. Based on the exhaust volume and the measured hydrogen concentration, the cumulative hydrogen exhaust is calculated for the calculation of the total hydrogen leakage test.

[0022] The beneficial effects of the present invention compared with the prior art are:

[0023] (1) The system adopts the method of replacing parts, which can realize the detection of various forms of hydrogen fuel cells and their applications such as fuel cells, engines, and small vehicles, including static leakage, vibration impact, cold and hot soak machine cycle start-up, and vibration table operation leakage, saving cost.

[0024] (2) Particularly suitable for testing the leakage of small fuel cells, especially air-cooled fuel cells, and the impact of operating conditions on leakage.

[0025] (3) While obtaining leakage data, the power generation efficiency of the battery stack and power generation system can also be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0027] Figure 1 Schematic diagram of static leakage test in the operation state of an air-cooled fuel cell stack with external hydrogen supply;

[0028] Figure 2 Schematic diagram of dynamic emission test with repeated working conditions on a vibration table for an air-cooled fuel cell stack with external hydrogen supply;

[0029] Figure 3 Schematic diagram of leakage test for light hydrogen electric vehicle with external hydrogen supply under rated working condition;

[0030] Figure 4 This is a schematic diagram of the vibration impact test of a water-cooled fuel cell stack with its own hydrogen in a non-operating state;

[0031] Figure 5 Schematic diagram of the hot and cold soak cycle test of the start-stop operation of a water-cooled fuel cell engine with its own hydrogen.

[0032] In the figure: 01. Test main cabin; 02. Circulating air outlet; 03. Outlet valve; 031. Outlet valve full circulation position; 032. Outlet valve fresh air position; 04. Circulating air inlet; 05. Inlet valve; 051. Inlet valve full circulation position; 052. Inlet valve fresh air position; 06. Fresh air temperature detector; 07. Fresh air speed detector; 08. Wind direction and speed detector; 09. Circulating air duct space; 10. Circulating fan; 11. Interlayer; 12. Humidification heat exchanger; 13. Temperature and humidity detector; 14. Oxygen concentration detector; 15. Pressure detector; 16. Wind speed detector; 17. Air inlet auxiliary cabin; 18. Front deflector; 19, front connection; 20. Movable bottom wheel of air inlet auxiliary cabin; 21. Test main cabin foot A; 22. Front stabilizer; 23. Test main cabin space; 24. Raw hydrogen connection port; 25. Test object; 251. Water-cooled fuel cell stack; 252. Light hydrogen electric vehicle; 26. Test object placement table; 261. Vibration table; 262. Temperature-controlled immersion machine table; 263. Roller table; 27. Hydrogen exhaust connection port; 28. Hydrogen concentration detector; 29. ​​Rear stabilizer; 30. Test main cabin foot B; 31. Movable bottom wheel of the air diversion and outlet auxiliary cabin; 32. Hydrogen exhaust pipe; 33. Tail exhaust buffer container; 34. Hydrogen exhaust flow detector; 35. Hydrogen exhaust temperature detector; 36. Tail exhaust buffer container outlet pipe; 37. Air diversion and outlet auxiliary cabin; 38. Rear guide plate; 39. Rear connection; 40. Fresh air induced draft fan; 41. Fresh air auxiliary cabin; 42. Front blind plate of circulating air duct; 43. Rear blind plate of circulating air duct. DETAILED DESCRIPTION

[0033] The present invention is described in detail below by specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0034] Small and medium-sized hydrogen fuel cells have a wide range of application scenarios. In fact, there is no absolute definition of so-called small and medium-sized. The present invention refers to being preferably used for less than 30kw, especially less than 10kw, but it does not limit the upper limit of the use of the present invention.

[0035] Depending on the test items, the components of the device of the present invention can be used locally and selectively to form various specific implementation methods, including but not limited to the following usage embodiments.

[0036] The test device can adopt a partial fresh air method with internal air circulation and partial ventilation, or a full fresh air method.

[0037] One of the ventilation control standards for some of its fresh air methods is safety, namely the hydrogen concentration limit.

[0038] The hydrogen content of the circulating air is obtained through a hydrogen detector, and the safety basis of the control index is the lower explosion limit of hydrogen.

[0039] The preferred data is based on the following: First, small air-cooled fuel cells generally have less hydrogen. For example, the total amount of hydrogen in a 5L 35MPa gas cylinder is no more than 110g, approximately 1.2m 3 . Simply according to the volume of the small test chamber L*W*H=2*2*3=12m 3 The hydrogen stack releases 10% of its hydrogen reserves, i.e. 11g, 0.12m 3 , in order to form an overall 1% hydrogen concentration in the space, and such a proportion of hydrogen release, including the exhaust hydrogen emission of the normal operation of the fuel cell, cannot be allowed by the high utilization and high efficiency requirements of the fuel cell itself even in a well-ventilated non-enclosed space, so the index should be smaller, so the maximum index should not exceed 0.1%. When the fresh air inlet is fully opened, if the hydrogen content still cannot be reduced, an alarm will be sounded, and at the same time, the introduction of fresh air will be maintained, the fuel cell power generation operation will be stopped, and the peripheral hydrogen supply will be stopped. Perform manual inspection according to the alarm. For the convenience of explanation, it is set to c a 1=0.5%.

[0040] The second control standard for ventilation is the limitation of the stack on the impact of hydrogen in the operating environment on cathode performance.

[0041] The hydrogen in the circulating air will participate in the cathode reaction in the cathode, reduce the cathode voltage, and protect the cathode, that is, the efficiency is reduced and the life is increased. This deviates from the actual stack test results and needs to be avoided. This data needs to be determined based on the performance of the membrane electrode used. It is generally obtained from the basic material test before stacking. For the convenience of explanation, it is set as c a 2=0.01%.

[0042] The third control standard for ventilation is that the oxidant content needs to be within the required range for stack operation.

[0043] In order to reduce the energy consumption of the fresh air heat exchange and the low-pressure introduction of fresh air, the proportion of fresh air, that is, the amount of fresh air introduced, can be reduced without affecting the operation of the fuel cell. The oxygen content is obtained through the oxygen content detector. When the oxygen content is less than or equal to the set required value for the operation of the fuel cell, the air exchange port is opened or opened more to obtain fresh air. The oxygen content is controlled at a specific value not lower than the local oxygen content, such as setting it to 95%, preferably not lower than 97%. For the convenience of explanation, the local oxygen content is set to 21%, and the control amount is set to c c 1=21%*0.95=20.0%.

[0044] See also Figures 1 to 5 ,in Figure 1 This is the basic structure of the test device.

[0045] The test device of the present invention comprises a test main cabin 01, an air inlet sub-cabin 17, an object to be tested 25, a test object placement table 26, an air outlet sub-cabin 37, and a tail exhaust buffer container 33. The device also comprises a fresh air sub-cabin 41 for replacing the air outlet sub-cabin 37. The side wall of the test main cabin 01 is provided with a raw hydrogen connection port 24, a hydrogen exhaust pipe 32 for anode tail gas discharge, as well as power cables, lighting, windows, control cables and other fluid connection pipelines not shown in the figure, and an alarm, a lifting ring, etc. are provided on the top.

[0046] The object to be tested 25 includes an air-cooled battery stack, a water-cooled battery stack 251, a light hydrogen electric vehicle 252, and other types of battery stack systems that need to be tested. The object placement table 26 includes a replacement vibration table 261, a temperature-controlled immersion table 262, and a roller table 263 for testing the operation of the light hydrogen electric vehicle 252.

[0047] The test main cabin 01 has a partition 11, which divides the test main cabin 01 into two parts: a test main cabin space 23 and a circulating air duct space 09. The diversion air inlet sub-cabin 17 is connected and sealed to the test main cabin 01 through the front connection 19 between the main cabin and the sub-cabin, and the diversion air outlet sub-cabin 37 is connected and sealed to the test main cabin 01 through the rear connection 39 between the main cabin and the sub-cabin, connecting the test main cabin space 23 and the circulating air duct space 09 to form an annular space. The front guide plate 18 in the diversion air inlet sub-cabin 17 and the rear guide plate 38 in the diversion air outlet sub-cabin 37 and the flow stabilizer 29 are used to stabilize the flow direction of the circulating air and reduce turbulence. The diversion air inlet sub-cabin 17 and the diversion air outlet sub-cabin 37 also have movable diversion air inlet sub-cabin movable bottom wheels 20 and diversion air outlet sub-cabin movable bottom wheels 31, respectively.

[0048] The circulating air duct space 09 has a circulating fan 10 and a humidifying heat exchanger 12. The top or side of the circulating air duct space 09 has a circulating air inlet 04 and a circulating air outlet 02, wherein the circulating air inlet 04 has an inlet valve 05, a fresh air temperature detector 06, and a fresh air speed detector 07.

[0049] At the front end of the test main cabin space 23, in front of the object to be tested 25, there are temperature and humidity detectors 13, oxygen concentration detectors 14, pressure detectors 15, and wind speed detectors 16. The humidifying heat exchanger 12 is provided with a cold source, a heat source, and spray water from outside the device. The test device adjusts the cold source, heat source, and spray water volume according to the test setting conditions and the test results of the temperature and humidity detector 13, the pressure detector 15, and the wind direction and wind speed detector 08. The humidifying heat exchanger 12 also has a water receiving tray to collect condensed water when the cold source is used. According to the data detected by the wind direction and wind speed detector 08, the speed of the circulating fan 10 is adjusted to keep the wind direction above the object to be tested consistent with the circulating wind direction to prevent the fan of the object to be tested from forming a local circulating airflow. The wind speed is preferably 0.5 to 2 m / s.

[0050] The test main cabin space 23 is provided with flow stabilizers in front and behind the object to be tested, namely, a front flow stabilizer 22 and a rear flow stabilizer 29. A wind direction and speed detector 08 is provided above the object to be tested 25, and a hydrogen concentration detector 28 is provided behind the object to be tested.

[0051] When the inlet valve 05 and the outlet valve 03 are fully closed, that is, they are respectively located at the inlet valve full circulation position 051 and the outlet valve full circulation position 031, the circulating fan 10 provides internal air flow circulation; when the inlet valve 05 and the outlet valve 03 are fully open, that is, they are respectively located at the inlet valve fresh air position 052 and the outlet valve fresh air position 032, the circulating fan 10 provides fresh air; when the inlet valve 05 and the outlet valve 03 are partially opened, the circulation formed by the circulating fan 10 is a mixed air formed by discharging part of the internal air and introducing part of the fresh air.

[0052] When the detected hydrogen concentration reaches the first limit value set by the system, that is, c a 1 concentration, the inlet valve 05 and the outlet valve 03 are opened to replace some fresh air to reduce the hydrogen concentration. When the detected oxygen concentration is lower than the first limit value set by the system, that is, c c 1 concentration, open the inlet valve 05 and the outlet valve 03 to replace part of the fresh air and increase the oxygen concentration.

[0053] The object to be detected 25 releases hydrogen, including tail gas emissions and other leaks. The anode hydrogen tail gas generated by the operation of the object to be detected 25 passes through the hydrogen discharge connection port 27, and then passes through the hydrogen discharge pipe 32 to reach the tail discharge buffer container 33. The tail discharge buffer container 33 has an inlet end and an outlet end, and has a hydrogen discharge flow detector 34 and a hydrogen discharge temperature detector 35 inside. The outlet end is connected to the tail discharge buffer container outlet pipe 36. The tail discharge hydrogen is finally discharged into the atmosphere or the atmospheric environment treatment system of the tail gas through the tail discharge buffer container outlet pipe 36. The bottom of the buffer container has a water diversion valve to automatically discharge liquid water. Preferably, the tail discharge buffer container 33 is located below and near the hydrogen discharge connection port 27.

[0054] The exhaust gas of the object to be tested 25 during operation is directly discharged into the circulation space of the test chamber through the exhaust emission path, thereby avoiding interference with the leakage of the object to be tested 25 and reducing the increase rate of hydrogen concentration in the circulating air.

[0055] Example 1

[0056] See also Figure 1 , static leakage test in the operation state of an air-cooled fuel cell stack with external hydrogen supply.

[0057] The detection device uses a combination of a test main cabin 01, an air inlet diversion sub-cabin 17, an air outlet diversion sub-cabin 37, and a tail exhaust buffer container 33.

[0058] In the test main cabin 01, the stack of the object to be tested 25 is placed on the test object placement table 26. By testing the outer wall of the main cabin 01, the stack of the object to be tested 25 is connected to hydrogen through the raw hydrogen connection port 24 in a pipeline manner, and external hydrogen is provided in accordance with the stack operation standard. Check whether there is hydrogen leakage in the gas supply pipe and the connection with the stack, such as using a soapy water leak detection method and a handheld hydrogen concentration detector detection method. The detector has a detection resolution of not less than 1ppm, and adjusts the connection to ensure that no leakage is introduced into each connection. Close the upper air inlet sub-cabin 17 and the air outlet sub-cabin 37.

[0059] The circulating fan 10 and the humidifying heat exchanger 12 are started and regulated by the detector data, including a temperature and humidity detector 13, an oxygen concentration detector 14, a pressure detector 15, a wind speed detector 16, a wind direction and speed detector 08, and a hydrogen concentration detector 28.

[0060] The battery stack of the object to be detected 25 is started and continuously operated, and the concentration c detected by the hydrogen concentration detector 28 is x , test chamber volume V, running time t x , the leakage rate of the detected object 25 is obtained as:

[0061] Q H =V*c x / t x

[0062] According to the set upper limit of hydrogen concentration c a 2 and c a 1, set the concentration of fresh air intake, that is, control the inlet valve 05 and the outlet valve 03 to be partially opened. Preferably, the opening degree reaches the continuous detection of the hydrogen concentration detector 28 detection data is c a 2 and c a 1 between 50% and 100% of the smallest.

[0063] When the inlet valve 05 and the outlet valve 03 are fully opened, that is, at the fresh air position, if the detected hydrogen concentration still exceeds the upper limit c a 2 and c a 1, an alarm is immediately sounded for inspection, and at the same time, the stack is stopped from outputting electricity, the supply of hydrogen to the stack is stopped, and the circulating fan 09 is kept on to reduce the hydrogen concentration.

[0064] When the oxygen concentration detected by the oxygen concentration detector 14 is lower than the first limit value set by the system, as shown in c c 1 = 20.0% concentration, then open the inlet valve 05 and the outlet valve 03 to replace part of the fresh air and increase the oxygen concentration to 20.5-21.0%.

[0065] When the inlet valve 05 and the outlet valve 03 are controlled to be fully open, that is, the fresh air position, if the detected oxygen concentration is still lower than the required value for the fuel cell operation, an alarm will be immediately sounded for inspection, and at the same time, the fuel cell output power and hydrogen supply to the fuel cell will be stopped, and the circulation fan 09 will continue to be turned on to reduce the hydrogen concentration.

[0066] When fresh air is introduced, the fresh air volume is calculated according to the wind speed measured by the fresh air speed detector 07 and converted into the circulating air discharge volume. According to the discharge volume and the measured hydrogen concentration, the cumulative hydrogen discharge volume is calculated for the calculation of the total hydrogen leakage volume tested.

[0067] Example 2

[0068] See also Figure 2 , dynamic emission tests with repeated operating conditions on an air-cooled fuel cell vibration table with external hydrogen supply.

[0069] Test the leakage changes of air-cooled fuel cell stack with external hydrogen supply during operation and under specific vibration.

[0070] The object to be tested 25 is an air-cooled fuel cell stack, which is placed on a vibration table 261 and runs continuously. The vibration table 261 vibrates according to the specific test settings to test the hydrogen leakage.

[0071] Example 3

[0072] See also Figure 3 , the light hydrogen electric vehicle 252 which does not need air supply treatment, uses fresh air, and supplies hydrogen externally is tested for leakage under rated working conditions. The aforementioned air inlet guide sub-cabin 17 and air outlet guide sub-cabin 37 are replaced with fresh air sub-cabin 41.

[0073] The test light hydrogen electric vehicle 252 is placed on the roller table 263 and runs continuously. The energy transmitted by the wheels is obtained through the resistance test of the roller table 263. The hydrogen leakage is tested by the hydrogen concentration detector 28 and the wind speed product. According to the vehicle speed setting, that is, the speed measured by the roller table 263, the speed obtained by the wind direction and wind speed detector 08 is kept within 10% of the deviation, and the speed obtained by the wind direction and wind speed detector 08 is kept not less than 0.1-0.5m / s, and the speed of the fresh air induced draft fan 40 is controlled. When the detection data of the hydrogen concentration detector 28 reaches the set upper limit of hydrogen concentration c a At 2 o'clock, alarm detection.

[0074] After the test set time, the operation is stopped, and the fresh air sub-cabin 41 is replaced with the guide air inlet sub-cabin 17 and the guide air outlet sub-cabin 37, and the light hydrogen electric vehicle 252 is tested, specifically:

[0075] (1) Leak detection in non-operating state

[0076] (2) Start idling detection

[0077] (3) Low power operation detection, such as 20% rated power output detection

[0078] Example 4

[0079] See also Figure 4 , vibration impact test of non-operating state of air-cooled fuel cell with built-in hydrogen.

[0080] The test stack is affected by the set frequency vibration. It mainly tests the leakage changes between the connectors, fasteners, seals, and stack plates after the stack has vibrated a certain number of times with the set frequency and amplitude.

[0081] Except that the stack system is not running, the difference from Example 1 is that the stack of the object to be tested 25 has its own hydrogen storage, and a vibration table 261 is used to perform a vibration test on the crystal form of the stack of the object to be tested 25, and the hydrogen concentration in the circulating gas is detected according to the set acceleration times or the set frequency and amplitude, and time.

[0082] During the test, if it is detected that the hydrogen concentration exceeds the standard, fresh air is introduced in the same manner as in Example 1 to reduce the hydrogen concentration.

[0083] Example 5

[0084] See also Figure 5 , hot and cold soak cycle test of start-stop operation of water-cooled fuel cell engine with its own hydrogen.

[0085] Test the leakage changes of the water-cooled fuel cell engine, including its own hydrogen tank, after multiple cold and hot soak cycles.

[0086] The test object 25 water-cooled fuel cell stack engine is equipped with a hydrogen cylinder. The temperature-controlled immersion machine 262 has a cold source and a heat source outside the test chamber. The engine is placed on the temperature-controlled immersion machine 262 and is frozen or heated according to the specific test settings. After reaching the set temperature, the repetitive cycle test of starting, running and stopping is completed. When the engine is in normal working condition, the hydrogen leakage is tested and the periodic leakage change is obtained.

[0087] The test of self-contained hydrogen focuses on start-stop periodic testing, without continuous long-term operation in between.

[0088] The above-described embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A normal pressure detection device for hydrogen fuel cell fuel leakage, characterized in that: The test main cabin (01) has a partition (11), and the partition (11) divides the test main cabin (01) into two parts: a test main cabin space (23) and a circulating air duct space (09). A test object placement table (26) is provided in the center of the test main cabin space (23) near the bottom. The test object (25) is placed on the test object placement table (26). The test object (25) is provided with a hydrogen discharge connection port (27). A wind direction and wind speed detector (08) is installed in the space above the test object (25), and a hydrogen concentration detector (28) is installed in the space behind the test object (25). The two ends of the test main cabin (01) are respectively provided with a front connection point (19) and a rear connection point (3 9), a wind speed detector (16), a pressure detector (15), an oxygen concentration detector (14), and a temperature and humidity detector (13) are sequentially arranged at one end of the test main cabin space (23) near the front connection (19), and a rear flow stabilizer (29) is arranged at one end of the test main cabin space (23) near the rear connection (39); a circulating air duct space (09) has a circulating fan (10) and a humidifying heat exchanger (12) inside, and a circulating air inlet (04) and a circulating air outlet (02) are arranged at the top of the circulating air duct space (09), wherein the circulating air inlet (04) has an inlet valve (05), a fresh air temperature detector (06), and a fresh air speed detector (07).

2. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 1, characterized in that: The test main cabin (01) is connected and sealed to the air inlet guide auxiliary cabin (17) via a front connection (19), and the test main cabin (01) is connected and sealed to the air outlet guide auxiliary cabin (37) via a rear connection (39), so that an annular space is formed by connecting the test main cabin space (23) and the circulating air duct space (09).

3. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 2, characterized in that: The air inlet diversion auxiliary cabin (17) has an air inlet diversion auxiliary cabin movable bottom wheel (20), and the air outlet diversion auxiliary cabin (37) has an air outlet diversion auxiliary cabin movable bottom wheel (31).

4. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 1, characterized in that: The hydrogen discharge connection port (27) is connected in sequence to the hydrogen discharge outlet pipe (32), the tail discharge buffer container (33), and the tail discharge buffer container outlet pipe (36); a hydrogen discharge flow detector (34) and a hydrogen discharge temperature detector (35) are provided in the tail discharge buffer container (33).

5. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 1, characterized in that: When hydrogen is supplied from outside, the object to be detected (25) is provided with a raw hydrogen connection port (24); when hydrogen is provided by itself, the object to be detected (25) is not provided with a raw hydrogen connection port (24).

6. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 2, characterized in that: The air outlet sub-chamber (37) is replaced by a fresh air sub-chamber (41), and a fresh air induced draft fan (40) is provided in the fresh air sub-chamber (41).

7. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 1, characterized in that: The detected object (25) includes, but is not limited to, an air-cooled fuel cell stack, a water-cooled fuel cell stack (251), and a light hydrogen electric vehicle (252).

8. The normal pressure detection device for hydrogen fuel cell fuel leakage according to claim 1, characterized in that: The test object placement table (26) includes, but is not limited to, a vibration table (261), a temperature-controlled immersion machine table (262), and a roller table (263) for testing the operation of a light hydrogen electric vehicle (252).

9. A normal pressure detection method for hydrogen fuel cell fuel leakage, characterized in that: When the inlet valve (05) and the outlet valve (03) are fully closed, the circulation fan (10) provides internal air flow circulation; when the inlet valve (05) and the outlet valve (03) are fully opened, the circulation fan (10) provides fresh air; when the inlet valve (05) is closed and the outlet valve (03) is opened, or when the inlet valve (05) is opened and the outlet valve (03) is closed, the circulation formed by the circulation fan (10) is mixed air formed by exhausting part of the internal air and introducing part of the fresh air; When the detected hydrogen concentration reaches the first limit value c set by the system a 1 concentration, the inlet valve (05) and the outlet valve (03) are opened to replace part of the fresh air and reduce the hydrogen concentration; when the detected oxygen concentration is lower than the first limit value c set by the system c When the concentration is 1, the inlet valve (05) and the outlet valve (03) are opened to replace part of the fresh air and increase the oxygen concentration; The anode hydrogen tail gas generated by the operation of the detected object (25) passes through the hydrogen discharge connection port (27), then through the hydrogen discharge outlet pipe (32) to the tail discharge buffer container (33), and finally discharged into the atmosphere or the atmospheric environment treatment system of the tail gas through the tail discharge buffer container outlet pipe (36); The specific steps include: placing the test object (25) battery stack on the test object placement table (26) in the test main cabin (01); connecting hydrogen to the test object (25) battery stack through the raw hydrogen connection port (24) in a pipeline manner through the outer wall of the test main cabin (01); detecting whether there is hydrogen leakage in the gas supply pipe and the connection between the battery stack and the gas stack; after confirming that there is no leakage, closing the upper air inlet auxiliary cabin (17) and the air outlet auxiliary cabin (37); starting the circulating fan (10) and the humidifying heat exchanger (12); controlling and starting the temperature and humidity detector (13), the oxygen concentration detector (14), the pressure detector (15), the wind speed detector (16), the wind direction and wind speed detector (08), and the hydrogen concentration detector (28) according to the detector data; and restarting the test object (25) battery stack for continuous operation; and according to the concentration c detected by the hydrogen concentration detector (28), x , test chamber volume V, running time t x The leakage rate of the object to be tested (25) is obtained as: Q H =V*c x / t x , according to the set upper limit of hydrogen concentration c a 2 and c a 1, setting the concentration of fresh air intake, i.e. controlling the inlet valve (05) and the outlet valve (03) to be partially opened; When the inlet valve (05) and the outlet valve (03) are both opened, if the detected hydrogen concentration still exceeds c a 2 and c a 1, an alarm is immediately sounded for inspection, and the stack is stopped from outputting electricity, the stack is stopped from supplying hydrogen, and the circulating fan (09) is continued to be turned on to reduce the hydrogen concentration; when the oxygen concentration detected by the oxygen concentration detector (14) is lower than the first limit value set by the system, the inlet valve (05) and the outlet valve (03) are opened to replace part of the fresh air, thereby increasing the oxygen concentration to 20.5-21.0%; When the inlet valve (05) and the outlet valve (03) are controlled to be fully opened, if the detected oxygen concentration is still lower than the required value for the operation of the fuel cell stack, an alarm is immediately sounded for inspection, and at the same time, the fuel cell stack is stopped from outputting electricity, the hydrogen supply to the fuel cell stack is stopped, and the circulating fan (09) is continued to be turned on to reduce the hydrogen concentration; when fresh air is introduced, the fresh air volume is calculated based on the wind speed measured by the fresh air speed detector (07), and converted into the circulating air discharge volume. Based on the discharge volume and the measured hydrogen concentration, the accumulated hydrogen discharge volume is calculated for the calculation of the total hydrogen leakage volume tested.

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