Hydrogen air pressure difference regulating device for fuel cell and fuel cell system

Abstract

The application provides a hydrogen-air pressure difference regulating device for a fuel cell and a fuel cell system, and belongs to the technical field of fuel cells. The device solves the problem that the prior art cannot synchronously, quickly and effectively regulate the hydrogen-air side pressure difference of a fuel cell. The device comprises an air side air chamber, an air side power coil, an armature, a hydrogen side power coil, a hydrogen side air chamber and a controller. The inlet of the air side air chamber is connected with the air path port of the fuel cell, and the inlet of the hydrogen side air chamber is connected with the hydrogen path port of the fuel cell. The opposite sides of the air side air chamber and the hydrogen side air chamber are each provided with a movable mechanism for sealing the air chamber and adjusting the size of the internal air cavity of the air chamber. The movable mechanism of the air side air chamber, the armature and the movable mechanism of the hydrogen side air chamber are sequentially fixed on the same moving shaft; and the distance between the initial positions of the air side power coil and the armature and the distance between the initial positions of the hydrogen side power coil and the armature are equal. The device can bidirectionally adjust the hydrogen-air side pressure difference, is placed outside the fuel cell stack and is convenient to detect and replace.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cells, in particular to a hydrogen-air pressure difference regulating device for fuel cells and a fuel cell system. BACKGROUND

[0002] Long-term stable operation of hydrogen fuel cells requires not only high proton conductivity, high chemical stability and low hydrogen leakage rate of proton exchange membranes, but also a certain mechanical strength of the proton exchange membranes to meet the dimensional deformation caused by changes in the working environment. Currently, the thickness of the proton exchange membrane is in the micron level. In order to avoid mechanical rupture, the hydrogen-air inlet pressure difference of the proton exchange membrane is usually required to be less than 50 kPa during operation.

[0003] However, when abnormal conditions occur during the operation of the fuel cell system, it is difficult to ensure that the hydrogen-air inlet pressure difference of the proton exchange membrane is within 50 kPa. In order to avoid damage to the proton exchange membrane, it is necessary to quickly and effectively regulate the hydrogen-air pressure difference of the fuel cell.

[0004] The prior art usually regulates the gas on one side of the proton exchange membrane separately. For example, patent CN112993326A sets a pressure balancing device in parallel on the air circuit, thereby controlling the air circuit pressure to make the hydrogen-air pressure in the fuel cell stack balanced. However, since it only regulates the pressure on one side, there are differences in response speed and control range between the flow control elements on both sides, and in the process of dynamic adjustment, the fuel cell anode and cathode are prone to large pressure difference, thereby affecting the service life of the fuel cell. SUMMARY

[0005] In view of the above analysis, the embodiments of the present application aim to provide a hydrogen-air pressure difference regulating device for fuel cells and a fuel cell system to solve the problem that the prior art cannot synchronously, quickly and effectively regulate the hydrogen-air pressure difference of the fuel cell.

[0006] In one aspect, the embodiments of the present application provide a hydrogen-air pressure difference regulating device for fuel cells, comprising a controller and, in the same direction, an air side air chamber (11b), an air side power coil (11e), an armature (11f), a hydrogen side power coil (11g), and a hydrogen side air chamber (11j) arranged in sequence.

[0007] The inlet (11a) of the air side gas chamber and the inlet (11k) of the hydrogen side gas chamber are connected with the air path port and the hydrogen path port of the fuel cell respectively; the opposite side of the air side gas chamber (11b) and the hydrogen side gas chamber (11j) is provided with a movable mechanism for sealing the gas chamber and adjusting the size of the internal air cavity; the movable mechanism (11D) of the air side gas chamber, the armature (11f) and the movable mechanism (11H) of the hydrogen side gas chamber are fixed on the same moving shaft in sequence; and the initial distance of the air side energizing coil (11e) from the armature (11f) and the initial distance of the hydrogen side energizing coil (11g) from the armature (11f) are equal.

[0008] A controller is used to monitor the pressure difference of the hydrogen path and the air path of the fuel cell, and to identify whether there is a risk of rupture of the proton exchange membrane according to the pressure difference; once there is, the hydrogen / air side energizing coil is powered according to the positive and negative of the pressure difference, so that the armature (11f) drives the movable mechanisms (11H, 11D) of the hydrogen side gas chamber and the air side gas chamber to move under the action of electromagnetic force until the risk of rupture disappears, and the above power supply is stopped.

[0009] The beneficial effects of the above technical solution are as follows: a hydrogen-air pressure difference regulating device arranged outside the fuel cell stack is provided, which can effectively prevent the proton exchange membrane from being damaged due to excessive pressure difference between the hydrogen path and the air path of the fuel cell. The device can bidirectionally and synchronously adjust the hydrogen-air pressure difference, and the control mode is simple and efficient. Moreover, it is arranged outside the fuel cell stack, which is convenient for detection and replacement, and the implementation mode is simple.

[0010] Based on the further improvement of the above device, the inlet (11a) of the air side gas chamber is connected with the air inlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen side gas chamber is connected with the hydrogen inlet of the fuel cell stack (4); or,

[0011] The inlet (11a) of the air side gas chamber is connected with the air tail gas outlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen side gas chamber is connected with the hydrogen tail gas outlet of the fuel cell stack (4).

[0012] Further, the shapes of the internal air cavities of the air side gas chamber (11b) and the hydrogen side gas chamber (11j) are the same, and the sizes of the air cavity volumes when each is not ventilated are the same; and,

[0013] The distance of the movable mechanism (11D) of the air side gas chamber from the armature (11f) and the distance of the movable mechanism (11H) of the hydrogen side gas chamber from the armature (11f) are the same;

[0014] The connecting pipeline of the inlet (11a) of the air chamber to the air path port of the fuel cell and the connecting pipeline of the inlet (11k) of the hydrogen chamber to the hydrogen path port of the fuel cell each comprise a high-temperature-resistant uniform inner diameter pipeline that can make the gas pressure at each transmission point consistent, and do not comprise an elbow and do not be provided with a check valve.

[0015] Further, the movable mechanism (11D, 11H) of the air chamber and the hydrogen chamber further comprises push plates (11d, 11h) and elastic diaphragms (11c, 11i) that are connected in sequence and are arranged at equal distances:

[0016] The elastic diaphragms (11c, 11i) are respectively arranged at the ends of the air chamber (11b) and the hydrogen chamber (11j), and are fixed to the moving shaft at one end through the push plate, for sealing the side chamber and adjusting the internal gas cavity volume of the hydrogen side chamber (11j) or the air side chamber (11b) under the pushing of the push plate.

[0017] Further, the controller further comprises the following which are connected in sequence:

[0018] The data acquisition unit is used for acquiring the hydrogen-air pressure difference at the inlet of the fuel cell stack, or the hydrogen-air pressure difference at the outlet, or the hydrogen-air pressure difference of the internal gas of the air chamber and the hydrogen chamber, as the gas pressure difference of the hydrogen path and the air path of the fuel cell, and sends the same to the data processing and control unit;

[0019] The data processing and control unit is used for identifying whether there is a risk of rupture of the proton exchange membrane according to the comparison of the received hydrogen-air pressure difference with a preset range, and once there is a risk, supplying power to the hydrogen / air side energizing coil according to the positive / negative direction of the hydrogen-air pressure difference, so that the elastic diaphragms (11c, 11i) of the hydrogen side chamber and the air side chamber are moved under the action of electromagnetic force, the gas cavity volume of the hydrogen side chamber and the air side chamber is changed, and the risk of rupture is identified again until the risk disappears, and the above power supply is stopped.

[0020] Further, the data acquisition unit further comprises:

[0021] The gas pressure sensors are respectively arranged on the internal gas cavity wall of the air chamber (11b) and the internal gas cavity wall of the hydrogen chamber (11j), and are used for acquiring the air pressure P c of the air chamber and the air pressure P a of the hydrogen chamber.

[0022] Further, the data processing and control unit executes the following program:

[0023] S1, after starting, acquiring the air pressure P c of the air chamber (11b) and the air pressure P a, and the hydrogen-air pressure difference Pa-Pc is obtained;

[0024] S2, compare the absolute value of the hydrogen-air pressure difference Pa-Pc with a preset threshold range to identify whether the proton exchange membrane is at risk of rupture; if the absolute value of the hydrogen-air pressure difference Pa-Pc is greater than the upper limit of the threshold range, it is determined that the proton exchange membrane is at risk of rupture, and step S3 is executed, otherwise, it is determined that the proton exchange membrane is not at risk of rupture, and the next moment of identification is continued;

[0025] S3, determine whether the hydrogen-air pressure difference Pa-Pc is greater than zero; if yes, execute step S4, otherwise, execute step S5;

[0026] S4, apply current to the air-side energized coil (11e), so that the armature (11f) moves along the horizontal direction to the air chamber (11b) under the action of electromagnetic force, drives the air-side elastic diaphragm (11c) to move to the direction of compressing the air in the air chamber through the air-side push plate (11d), so that the air cavity volume of the air chamber (11b) decreases and the air pressure increases, and at the same time, the hydrogen-side elastic diaphragm (11i) is driven to move to the direction of expanding the air in the air chamber through the hydrogen-side push plate (11h), so that the air cavity volume of the hydrogen-side air chamber (11j) increases and the air pressure decreases, and then step S6 is executed;

[0027] S5, apply current to the hydrogen-side energized coil (11g), so that the armature (11f) moves along the horizontal direction to the hydrogen-side air chamber (11j) under the action of electromagnetic force, drives the hydrogen-side elastic diaphragm (11i) to move to the direction of compressing the air in the hydrogen-side air chamber through the hydrogen-side push plate (11h), so that the air cavity volume of the hydrogen-side air chamber (11j) decreases and the air pressure increases, and at the same time, the air-side elastic diaphragm (11c) is driven to move to the direction of expanding the air in the air chamber through the air-side push plate (11d), so that the air cavity volume of the air chamber increases and the air pressure decreases, and then step S6 is executed;

[0028] S6, monitor the hydrogen-air pressure difference Pa-Pc in real time during the above movement process until the absolute value of Pa-Pc within a preset time falls within the preset threshold range, it is determined that the risk of rupture disappears, and the above power supply is stopped.

[0029] Further, the data processing and control unit further executes the following program:

[0030] S401, obtain the air pressure P of the air entering the stack at the current moment c1 , the air pressure P of the hydrogen entering the stack a1 , determine the air pressure difference P c1 -P c , P a1 -P a ;

[0031] S402, according to the above air pressure difference P c1-P c 、P a1 -P a , in combination with the hydrogen-air pressure difference Pa-Pc, the amplitude I of the current is determined by the following formula

[0032] I=f(P c1 -P c , P a1 -P a , Pa-Pc, L1, N1, L2, N2)

[0033] In the formula, L1 is the distance between the air-side energizing coil and the armature, N1 is the number of turns of the air-side energizing coil, L2 is the distance between the hydrogen-side energizing coil (11g) and the armature, N2 is the number of turns of the hydrogen-side energizing coil, and f is a fitting function.

[0034] Further, the hydrogen-side energizing coil (11g) and the air-side energizing coil (11e) are fixed to the moving shaft, and the winding direction of each coil is perpendicular to the axis direction of the moving shaft.

[0035] The distance between the air-side energizing coil (11e) and the armature (11f) is equal to the distance between the hydrogen-side energizing coil (11g) and the armature (11f).

[0036] Compared with the prior art, the present application can achieve at least one of the following beneficial effects:

[0037] 1. The gas on both sides of the proton exchange membrane can be automatically regulated synchronously, and the regulation effect is good.

[0038] 2. The structure is simple, and the control method is simple and flexible.

[0039] 3. The elastic diaphragm is fixedly connected with the air chamber structure, thereby ensuring the sealing effect of the air chamber, and the sealing structure is simple to implement. In addition, the elastic diaphragm structure has a certain elasticity and can be deformed, stretched and contracted under extrusion.

[0040] On the other hand, the present application provides a fuel cell system, which comprises the hydrogen-air pressure difference regulating device (11) described above, and a fuel cell stack (4), an air inlet control device, a hydrogen inlet control device, an air exhaust control device, and a hydrogen exhaust control device.

[0041] The air inlet control device is arranged at the air inlet of the fuel cell stack (4) and further comprises an air compressor (1), an intercooler (2), an air control valve (3), and an air inlet manifold (4a) connected in sequence.

[0042] The hydrogen gas inlet control device is arranged at the hydrogen gas inlet of the fuel cell stack (4), and further comprises a hydrogen cylinder (6), an ejector (7), a hydrogen injection device (8), and a hydrogen inlet manifold (4c) connected in sequence.

[0043] The air tail gas control device is arranged at the air tail gas outlet of the fuel cell stack (4), and further comprises an air outlet manifold (4b) and a tail gas exhaust valve (5) connected in sequence.

[0044] The hydrogen tail gas control device is arranged at the hydrogen tail gas outlet of the fuel cell stack (4), and further comprises a hydrogen outlet manifold (4d), a water separator (9), and a tail gas exhaust valve (10); the exhaust port of the water separator (9) is connected with the flow inlet of the ejector (7), and the water outlet thereof is connected with the tail gas exhaust valve (10).

[0045] The inlet (11a) of the air side gas chamber of the differential pressure control device (11) is connected with the air inlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen side gas chamber is connected with the hydrogen gas inlet of the fuel cell stack (4); or,

[0046] The inlet (11a) of the air side gas chamber of the differential pressure control device (11) is connected with the air tail gas outlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen side gas chamber is connected with the hydrogen tail gas outlet of the fuel cell stack (4).

[0047] The summary is provided to introduce a selection of concepts in a simplified form, which will be further described below in the detailed description. The summary is not intended to identify key or essential features of the disclosure, nor is it intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0048] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout the different views of the drawings.

[0049] Figure 1 A schematic diagram of the hydrogen-air differential pressure control device for the fuel cell of Example 1 is shown.

[0050] Figure 2 A schematic diagram of the hydrogen-air differential pressure control device for the fuel cell of Example 2 is shown.

[0051] Figure 3 A schematic diagram of the fuel cell system of Example 3 is shown.

[0052] REFERENCE NUMERALS:

[0053] 1 - Air compressor; 2 - Intercooler; 3 - Air control valve; 4 - Fuel cell stack;

[0054] 4a - Air inlet manifold; 4b - Air outlet manifold; 4c - Hydrogen inlet manifold;

[0055] 4d - Hydrogen outlet manifold; 5 - Tailpipe throttle; 6 - Hydrogen bottle; 7 - Ejector;

[0056] 8 - Hydrogen injection device; 9 - Water trap; 10 - Tailpipe valve; 11 - Hydrogen air pressure difference regulating device;

[0057] 11a - Inlet of air side air chamber; 11b - Air side air chamber; 11c - Air side elastic diaphragm;

[0058] 11d - Air side push plate; 11e - Air side electric coil; 11f - Armature;

[0059] 11g - Hydrogen side electric coil; 11h - Hydrogen side push plate; 11i - Hydrogen side elastic diaphragm;

[0060] 11j - Hydrogen side air chamber; 11k - Inlet of hydrogen side air chamber;

[0061] 11D - Moving mechanism of air side air chamber; 11H - Moving mechanism of hydrogen side air chamber;

[0062] 12 - DCDC converter. DETAILED DESCRIPTION

[0063] Embodiments of the present disclosure will be described in more detail with reference to the drawings. Although embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0064] The term "comprising" and variations thereof as used herein are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Unless otherwise expressly stated, the term "or" refers to an inclusive "or" and not to an exclusive "or". The term "based on" means "based at least in part on". The terms "one example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "a first", "a second", etc. can refer to different or the same objects. Other explicit or implicit definitions can also be included below.

[0065] Embodiment 1

[0066] One embodiment of the present disclosure discloses a hydrogen air pressure difference regulating device for fuel cell, such as Figure 1As shown, it comprises a controller and sequentially arranged in the same direction, an air side air chamber 11b, an air side energizing coil 11e, an armature 11f, a hydrogen side energizing coil 11g, and a hydrogen side air chamber 11j.

[0067] The inlet 11a of the air side air chamber and the inlet 11k of the hydrogen side air chamber are respectively connected with the air path port and the hydrogen path port of the fuel cell. That is, the inlet 11a of the air side air chamber is connected with the air path port of the fuel cell, and the inlet 11k of the hydrogen side air chamber is connected with the hydrogen path port of the fuel cell.

[0068] The opposite side of the air side air chamber 11b and the hydrogen side air chamber 11j is respectively provided with a movable mechanism for sealing the air chamber and adjusting the size of the internal air cavity. The movable mechanism 11D of the air side air chamber, the armature 11f, and the movable mechanism 11H of the hydrogen side air chamber are sequentially fixed on the same moving shaft; and the initial position distance of the air side energizing coil 11e from the armature 11f and the initial position distance of the hydrogen side energizing coil 11g from the armature 11f are equal.

[0069] It should be noted that the air side energizing coil 11e and the hydrogen side energizing coil 11g can not be arranged on the above-mentioned moving shaft, and the movement of the armature can also be ensured. The hydrogen path port of the fuel cell comprises a hydrogen inlet and a hydrogen tail gas outlet, and the air path port comprises an air inlet and an air tail gas outlet.

[0070] In addition to the structure described in Embodiment 2, the above-mentioned movable mechanism (11D, 11H) can also refer to patents CN201920651739.7 and CN202121830082.4.

[0071] The controller is used to monitor the gas pressure difference of the hydrogen path and the air path of the fuel cell, and to identify whether there is a risk of rupture of the proton exchange membrane according to the gas pressure difference. Once there is a risk, the hydrogen / air side energizing coil is powered according to the positive / negative of the gas pressure difference, so that the armature 11f drives the movable mechanisms 11H, 11D of the hydrogen side air chamber and the air side air chamber to move under the action of electromagnetic force until the risk of rupture disappears, and the above-mentioned power supply is stopped.

[0072] When the gas pressure difference of the hydrogen path and the air path of the fuel cell exceeds the preset range (within 50 kPa), and when the gas pressure difference is greater than zero, the air side energizing coil 11g is powered, and the armature 11f moves in the direction of the air side air chamber 11b under the action of electromagnetic force, driving the movable mechanisms 11D, 11H of the air side air chamber and the hydrogen side air chamber to move in the direction of the air side air chamber 11b, thereby reducing the hydrogen pressure of the hydrogen path of the fuel cell; when the gas pressure difference is less than zero, the hydrogen side energizing coil 11g is powered, and the armature 11f moves in the direction of the hydrogen side air chamber 11j under the action of electromagnetic force, driving the movable mechanisms 11D, 11H of the air side air chamber and the hydrogen side air chamber to move in the direction of the hydrogen side air chamber 11j, thereby reducing the air pressure of the air path of the fuel cell.

[0073] Compared with the prior art, the embodiment provides a hydrogen-air pressure difference regulating device arranged outside a fuel cell stack, which can effectively prevent the proton exchange membrane from being damaged due to excessive pressure difference between the hydrogen path and the air path of the fuel cell. The device can bidirectionally and synchronously regulate the pressure difference between the hydrogen side and the air side, and the control mode is simple and efficient. Moreover, the device is arranged outside the fuel cell stack, so that it is convenient to detect and replace, and the implementation mode is simple.

[0074] Embodiment 2

[0075] On the basis of embodiment 1, the inlet 11a of the air side gas chamber is connected with the air inlet of the fuel cell stack 4, and the inlet 11k of the hydrogen side gas chamber is connected with the hydrogen inlet of the fuel cell stack 4; or the inlet 11a of the air side gas chamber is connected with the air tail gas outlet of the fuel cell stack 4, and the inlet 11k of the hydrogen side gas chamber is connected with the hydrogen tail gas outlet of the fuel cell stack 4.

[0076] Preferably, the hydrogen-air pressure difference regulating device further comprises a DCDC converter 12, as shown in the figure. The controller is connected with the power supply end of the air side energizing coil 11e and the hydrogen side energizing coil 11g through the DCDC converter 12. Figure 2

[0077] Preferably, the internal cavities of the air side gas chamber 11b and the hydrogen side gas chamber 11j are of the same shape, and the cavity volumes of each when not being ventilated are the same. Moreover, the distance between the moving mechanism 11D of the air side gas chamber and the armature 11f and the distance between the moving mechanism 11H of the hydrogen side gas chamber and the armature 11f are the same.

[0078] Preferably, the connecting pipeline of the inlet 11a of the air side gas chamber to the air path port of the fuel cell and the connecting pipeline of the inlet 11k of the hydrogen side gas chamber to the hydrogen path port of the fuel cell each comprise a high-temperature-resistant uniform inner diameter pipeline capable of making the gas pressure at each transmission point consistent, and do not comprise an elbow and are not provided with a check valve.

[0079] Preferably, the moving mechanisms 11D and 11H of the air side gas chamber and the hydrogen side gas chamber further comprise push plates 11d and 11h and elastic diaphragms 11c and 11i which are connected in sequence and arranged at equal distances.

[0080] The elastic diaphragms 11c and 11i are respectively arranged at the ends of the air side gas chamber 11b and the hydrogen side gas chamber 11j, and are fixed to a moving shaft at one end through the push plates, for sealing the side gas chamber and moving under the pushing of the push plates to adjust the internal cavity volume of the hydrogen side gas chamber 11j or the air side gas chamber 11b.

[0081] The hydrogen side push plate 11h and the air side push plate 11d are connected to the same moving shaft, and the armature is arranged in the middle and is made of a magnetic material, and can be synchronously moved left and right in the horizontal direction.

[0082] ​Preferably, the controller further comprises a data acquisition unit, a data processing and control unit connected in sequence.

[0083] The data acquisition unit is configured to acquire the hydrogen-air pressure difference at the inlet of the fuel cell stack, or the hydrogen-air pressure difference at the outlet of the fuel cell stack, or the hydrogen-air pressure difference between the gas chambers on the hydrogen side and the air side, as the pressure difference between the hydrogen path and the air path of the fuel cell, and send the hydrogen-air pressure difference to the data processing and control unit.

[0084] The data processing and control unit is configured to compare the received hydrogen-air pressure difference with a preset range to identify whether the proton exchange membrane is at risk of rupture, and once at risk, supply power to the hydrogen / air side power coil according to the positive / negative direction of the hydrogen-air pressure difference, so that the armature 11f drives the elastic diaphragms 11H and 11D of the hydrogen side gas chamber and the air side gas chamber to move under the action of electromagnetic force, so that the volume of the gas cavity of the hydrogen side gas chamber and the air side gas chamber changes, and the identification is repeated until the risk of rupture disappears, and the power supply is stopped.

[0085] Preferably, the data acquisition unit further comprises a plurality of gas pressure sensors.

[0086] Each gas pressure sensor is arranged on the inner cavity wall of the air side gas chamber 11b and the inner cavity wall of the hydrogen side gas chamber 11j, respectively, and is configured to acquire the air pressure P c and the hydrogen pressure P a .

[0087] Preferably, the data processing and control unit executes the following program:

[0088] S1, after starting, acquiring the air pressure P c and the hydrogen pressure P a of the air side gas chamber 11b and the hydrogen side gas chamber 11j at the current time, and obtaining the hydrogen-air pressure difference Pa-Pc;

[0089] S2, comparing the absolute value of the hydrogen-air pressure difference Pa-Pc with a preset threshold range to identify whether the proton exchange membrane is at risk of rupture; if the absolute value of the hydrogen-air pressure difference Pa-Pc is greater than the upper limit of the threshold range, it is determined that the proton exchange membrane is at risk of rupture, and step S3 is executed, otherwise, it is determined that the proton exchange membrane is not at risk of rupture, and the identification at the next time is continued;

[0090] S3, determining whether the hydrogen-air pressure difference Pa-Pc is greater than zero; if yes, step S4 is executed, otherwise, step S5 is executed;

[0091] S4, current is applied to the empty side energizing coil 11e, so that the armature 11f moves to the empty side air chamber 11b under the action of electromagnetic force along the horizontal direction, the empty side elastic diaphragm 11c is driven by the empty side push plate 11d to move to the direction of compressing the gas in the empty side air chamber, so that the air cavity volume of the empty side air chamber 11b decreases and the air pressure increases, at the same time, the hydrogen side elastic diaphragm 11i is driven by the hydrogen side push plate 11h to move to the direction of expanding the gas in the hydrogen side air chamber, so that the air cavity volume of the hydrogen side air chamber 11j increases and the air pressure decreases, then step S6 is executed;

[0092] S5, current is applied to the hydrogen side energizing coil 11g, so that the armature 11f moves to the hydrogen side air chamber 11j under the action of electromagnetic force along the horizontal direction, the hydrogen side elastic diaphragm 11i is driven by the hydrogen side push plate 11h to move to the direction of compressing the gas in the hydrogen side air chamber, so that the air cavity volume of the hydrogen side air chamber 11j decreases and the air pressure increases, at the same time, the empty side elastic diaphragm 11c is driven by the empty side push plate 11d to move to the direction of expanding the gas in the empty side air chamber, so that the air cavity volume of the empty side air chamber increases and the air pressure decreases, then step S6 is executed;

[0093] S6, the hydrogen-air pressure difference Pa-Pc is monitored in real time during the above movement, until the absolute value of Pa-Pc in the preset time falls within the preset threshold range, it is determined that the rupture risk disappears, and the above power supply is stopped.

[0094] Preferably, the data processing and control unit further executes the following program:

[0095] S401, the air pressure P of the current time into the stack is obtained c1 , the air pressure P of the hydrogen into the stack is obtained a1 , the air pressure difference P c1 -P c , P a1 -P a ;

[0096] S402, according to the above air pressure difference P c1 -P c , P a1 -P a , combined with the hydrogen-air pressure difference Pa-Pc, the amplitude I of the current is determined by the following formula

[0097] I=f(P c1 -P c , P a1 -P a , Pa-Pc, L1, N1, L2, N2)

[0098] In the formula, L1 is the distance between the air-side energizing coil and the armature, N1 is the number of turns of the air-side energizing coil, L2 is the distance between the hydrogen-side energizing coil 11g and the armature, N2 is the number of turns of the hydrogen-side energizing coil, and f is the fitting function of the shortest state of the hydrogen-air pressure difference adjustment time calibrated in the laboratory.

[0099] Preferably, the data processing and control unit has a display module.

[0100] The display screen of the display module displays the air pressure P c1 of the air-side air chamber 11b at the current time a1 , the air pressure P c1 of the hydrogen-side air chamber 11j, and the result that the proton exchange membrane is at risk of rupture if P a1 -P c1 falls outside the preset range or the result that the proton exchange membrane is not at risk of rupture if P a1 -P a1 falls within the preset range.

[0101] Preferably, the hydrogen-side energizing coil (11g) and the air-side energizing coil 11e are both fixed to the moving shaft, and the winding direction of each coil is perpendicular to the axis direction of the moving shaft. The distance between the air-side energizing coil 11e and the armature 11f is equal to the distance between the hydrogen-side energizing coil (11g) and the armature 11f.

[0102] In implementation, the following connection mode can be used: the inlet 11a of the air-side air chamber is connected to the air tail gas outlet of the fuel cell stack 4, and the inlet 11k of the hydrogen-side air chamber is connected to the hydrogen tail gas outlet of the fuel cell stack 4. The gas-liquid mixture flowing out of the air outlet manifold 4b enters the air-side air chamber 11b from the inlet 11a of the air-side air chamber, and the entire flow cannot contain a flow-blocking elbow, etc., and the flow is smooth, ensuring that the pressure in the air chamber is close to the pressure of the stack. The air chamber is connected only to the air path of the fuel cell stack, and the air-side elastic diaphragm 11c is arranged at the end. The structure has a certain elasticity and can be deformed under pressure, and can be stretched and contracted. At the same time, it is fixedly connected with the structure of the air chamber and has a sealing effect. Similarly, the hydrogen side has the same arrangement as described above.

[0103] Compared with Example 1, the device described in this embodiment has the following beneficial effects:

[0104] 1. The gas on both sides of the proton exchange membrane can be automatically regulated synchronously, and the regulation effect is good.

[0105] 2. The structure is simple, and the control mode is simple and flexible.

[0106] 3. The elastic diaphragm is arranged to be connected and fixed with the air chamber structure, so as to ensure the sealing effect of the air chamber, and the sealing structure is simple to implement. In addition, the elastic diaphragm structure has a certain elasticity and can be deformed under extrusion, and can be stretched and contracted.

[0107] Embodiment 3

[0108] The application also provides a fuel cell system, comprising a hydrogen-air pressure difference regulating device 11, and a fuel cell stack 4, an air inlet control device, a hydrogen inlet control device, an air tail gas control device, and a hydrogen tail gas control device.

[0109] The air inlet control device is arranged at the air inlet of the fuel cell stack 4 and further comprises an air compressor 1, an intercooler 2, an air control valve 3, and an air inlet manifold 4a connected in sequence.

[0110] The hydrogen inlet control device is arranged at the hydrogen inlet of the fuel cell stack 4 and further comprises a hydrogen cylinder 6, an ejector 7, a hydrogen injection device 8, and a hydrogen inlet manifold 4c connected in sequence.

[0111] The air tail gas control device is arranged at the air tail gas outlet of the fuel cell stack 4 and further comprises an air outlet manifold 4b and a tail gas exhaust valve 5 connected in sequence.

[0112] The hydrogen tail gas control device is arranged at the hydrogen tail gas outlet of the fuel cell stack 4 and further comprises a hydrogen outlet manifold 4d, a water separator 9, and a tail gas exhaust valve 10; the exhaust port of the water separator 9 is connected with the flow inlet of the ejector 7, and the water outlet thereof is connected with the tail gas exhaust valve 10.

[0113] The inlet 11a of the air side air chamber of the pressure difference regulating device 11 is connected with the air inlet of the fuel cell stack 4, and the inlet 11k of the hydrogen side air chamber is connected with the hydrogen inlet of the fuel cell stack 4; or the inlet 11a of the air side air chamber of the pressure difference regulating device 11 is connected with the air tail gas outlet of the fuel cell stack 4, and the inlet 11k of the hydrogen side air chamber is connected with the hydrogen tail gas outlet of the fuel cell stack 4.

[0114] The above has described the embodiments of the present disclosure, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles, practical applications, or improvements of the prior art of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A hydrogen-air differential pressure control device for fuel cells, characterized in that, The hydrogen-air pressure differential control device (11) is applied to a fuel cell system. The hydrogen-air pressure differential control device for fuel cells includes a controller and an air-side chamber (11b), an air-side energizing coil (11e), an armature (11f), a hydrogen-side energizing coil (11g), and a hydrogen-side chamber (11j) arranged sequentially in the same direction. The inlet (11a) of the air-side gas chamber and the inlet (11k) of the hydrogen-side gas chamber are connected to the air passage port and the hydrogen passage port of the fuel cell, respectively; the air-side gas chamber (11b) and the hydrogen-side gas chamber (11j) are each provided with a movable mechanism for sealing the gas chamber and adjusting the size of the internal gas cavity; the movable mechanism (11D) of the air-side gas chamber, the armature (11f), and the movable mechanism (11H) of the hydrogen-side gas chamber are fixed on the same moving shaft in sequence; and the initial positions of the air-side energizing coil (11e) and the armature (11f) are equal. The controller is used to monitor the pressure difference between the hydrogen and air paths of the fuel cell; and to identify whether there is a risk of rupture of the proton exchange membrane based on the pressure difference. If there is, the controller supplies power to the corresponding hydrogen / air side energizing coil according to the positive or negative direction of the pressure difference, so that the armature (11f) drives the moving mechanism (11H, 11D) of the hydrogen side chamber and the air side chamber to move under the action of electromagnetic force until the risk of rupture disappears and the power supply is stopped. The moving mechanisms (11D, 11H) of the air-side gas chamber and the hydrogen-side gas chamber further include push plates (11d, 11h) and elastic diaphragms (11c, 11i) that are connected in sequence and equidistant from each other: Elastic diaphragms (11c, 11i) are respectively located at the ends of the air-side gas chamber (11b) and the hydrogen-side gas chamber (11j). One end is fixed to the moving shaft via a push plate. These diaphragms are used to seal the gas chamber and move under the push of the push plate to adjust the internal gas volume of the hydrogen-side gas chamber (11j) or the air-side gas chamber (11b). The controller further includes, in sequence, the following: The data acquisition unit is used to acquire the hydrogen-air pressure difference at the inlet of the fuel cell stack, or the hydrogen-air pressure difference at the outlet, or the hydrogen-air pressure difference between the gas inside the air-side chamber and the hydrogen-side chamber in real time, as the gas pressure difference between the hydrogen path and the air path of the fuel cell, and send it to the data processing and control unit. The data processing and control unit is used to identify whether there is a risk of rupture of the proton exchange membrane by comparing the received hydrogen-air pressure difference with a preset range. If there is a risk, the unit supplies power to the hydrogen / air side energizing coils corresponding to the positive / negative hydrogen-air pressure difference, so that the armature (11f) moves the elastic membranes (11c, 11i) of the hydrogen-side gas chamber and the air-side gas chamber under the action of electromagnetic force, thereby changing the gas chamber volume of the hydrogen-side gas chamber and the air-side gas chamber. The unit then identifies the risk of rupture again until the risk of rupture disappears, at which point the power supply is stopped.

2. The hydrogen-air differential pressure control device for fuel cells according to claim 1, characterized in that, The inlet (11a) of the air-side gas chamber is connected to the air inlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen-side gas chamber is connected to the hydrogen inlet of the fuel cell stack (4); or, the inlet (11a) of the air-side gas chamber is connected to the air exhaust outlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen-side gas chamber is connected to the hydrogen exhaust outlet of the fuel cell stack (4).

3. The hydrogen-air differential pressure control device for fuel cells according to claim 2, characterized in that, The air-side gas chamber (11b) and the hydrogen-side gas chamber (11j) have the same internal gas cavity shape, and their respective gas cavity volumes are the same when no gas is supplied; furthermore... The distance between the moving mechanism (11D) of the air-side gas chamber and the armature (11f) of the moving mechanism (11H) of the hydrogen-side gas chamber is the same; The connecting pipe from the inlet (11a) of the air-side gas chamber to the air port of the fuel cell, and the connecting pipe from the inlet (11k) of the hydrogen-side gas chamber to the hydrogen port of the fuel cell, both include high-temperature resistant pipes with uniform inner diameters that allow the gas pressure to be consistent at each transmission point, and do not include elbows or shut-off valves.

4. The hydrogen-air differential pressure control device for fuel cells according to any one of claims 1-3, characterized in that, The data acquisition unit further includes: Pressure sensors are respectively installed on the inner wall of the air-side gas chamber (11b) and the inner wall of the hydrogen-side gas chamber (11j) to obtain the gas pressure P of the air-side gas chamber. c The gas pressure P in the hydrogen-side gas chamber a .

5. The hydrogen-air differential pressure control device for fuel cells according to claim 4, characterized in that, The data processing and control unit executes the following program; S1. After startup, obtain the air pressure P of the air-side chamber (11b) at the current time. c The gas pressure P in the hydrogen-side gas chamber (11j) a The hydrogen-air pressure difference Pa-Pc was obtained; S2. Compare the absolute value of the hydrogen-air pressure difference Pa-Pc with a preset threshold range to identify whether there is a risk of rupture in the proton exchange membrane. If the absolute value of the hydrogen-air pressure difference Pa-Pc is greater than the upper limit of the threshold range, it is determined that there is a risk of rupture in the proton exchange membrane, and step S3 is executed. Otherwise, it is determined that there is no risk of rupture in the proton exchange membrane, and the identification at the next moment continues. S3. Determine if the hydrogen-air pressure difference Pa-Pc is greater than zero; if yes, proceed to step S4; otherwise, proceed to step S5. S4. Apply current to the air-side energized coil (11e) so that the armature (11f) moves horizontally towards the air-side gas chamber (11b) under the action of electromagnetic force. The air-side pusher plate (11d) drives the air-side elastic diaphragm (11c) to move in the direction of compressing the gas in the air-side gas chamber, so that the gas chamber volume of the air-side gas chamber (11b) decreases and the gas pressure increases. At the same time, the hydrogen-side pusher plate (11h) drives the hydrogen-side elastic diaphragm (11i) to move in the direction of expanding the gas in the air-side gas chamber, so that the gas chamber volume of the hydrogen-side gas chamber (11j) increases and the gas pressure decreases. Then, execute step S6. S5. Apply current to the hydrogen-side energized coil (11g) so that the armature (11f) moves horizontally towards the hydrogen-side gas chamber (11j) under the action of electromagnetic force. The hydrogen-side pusher plate (11h) drives the hydrogen-side elastic diaphragm (11i) to move in the direction of compressing the gas in the hydrogen-side gas chamber, so that the gas chamber volume of the hydrogen-side gas chamber (11j) decreases and the gas pressure increases. At the same time, the air-side pusher plate (11d) drives the air-side elastic diaphragm (11c) to move in the direction of expanding the gas in the air-side gas chamber, so that the gas chamber volume of the air-side gas chamber increases and the gas pressure decreases. Then, execute step S6. S6. During the above-mentioned movement process, monitor the hydrogen-air pressure difference Pa-Pc in real time until the absolute value of Pa-Pc within a preset time period falls within the preset threshold range, determine that the risk of rupture has disappeared, and stop the above-mentioned power supply.

6. The hydrogen-air differential pressure control device for fuel cells according to claim 5, characterized in that, The data processing and control unit also executes the following program: S401, Obtain the current pressure P of the incoming air. c1 The pressure P of the hydrogen gas fed into the pile a1 Determine the pressure difference P c1 -P c P a1 -P a ; S402, based on the above pressure difference P c1 -P c P a1 -P a Combining the hydrogen-air pressure difference Pa-Pc, the current amplitude I is determined using the following formula. I=f(P c1 -P c ,P a1 -P a ,Pa-Pc,L1,N1,L2,N2) In the formula, L1 is the distance between the empty-side energized coil and the armature, N1 is the number of coils in the empty-side energized coil, L2 is the distance between the hydrogen-side energized coil (11g) and the armature, N2 is the number of coils in the hydrogen-side energized coil, and f is the fitting function.

7. The hydrogen-air differential pressure control device for fuel cells according to any one of claims 1, 2, 3, 5, and 6, characterized in that, The hydrogen-side energized coil (11g) and the air-side energized coil (11e) are both fixed on the moving shaft, and the winding direction of each coil is perpendicular to the axial direction of the moving shaft. The distances between the air-side energized coil (11e) and the armature (11f), and between the hydrogen-side energized coil (11g) and the armature (11f) are equal.

8. A fuel cell system, characterized in that, Includes the hydrogen-air pressure differential control device (11) as described in any one of claims 1-7, and a fuel cell stack (4), an air intake control device, a hydrogen intake control device, an air exhaust control device, and a hydrogen exhaust control device; wherein, The air intake control device is located at the air inlet of the fuel cell stack (4) and further includes an air compressor (1), an intercooler (2), an air control valve (3), and an air inlet manifold (4a) connected in sequence. The hydrogen inlet control device is located at the hydrogen inlet of the fuel cell stack (4) and further includes a hydrogen cylinder (6), an ejector (7), a hydrogen injection device (8), and a hydrogen inlet manifold (4c) connected in sequence. The air exhaust control device is located at the air exhaust outlet of the fuel cell stack (4) and further includes an air outlet manifold (4b) and an exhaust throttle valve (5) connected in sequence. The hydrogen tail gas control device is located at the hydrogen tail gas outlet of the fuel cell stack (4), and further includes a hydrogen outlet manifold (4d), a water distributor (9), and a tail gas valve (10); the exhaust port of the water distributor (9) is connected to the inlet of the ejector (7), and its drain port is connected to the tail gas valve (10). The inlet (11a) of the air-side gas chamber of the differential pressure control device (11) is connected to the air inlet of the fuel cell stack (4), and the inlet (11k) of the hydrogen-side gas chamber is connected to the hydrogen inlet of the fuel cell stack (4); or, The air-side gas chamber inlet (11a) of the differential pressure control device (11) is connected to the air exhaust outlet of the fuel cell stack (4), and the hydrogen-side gas chamber inlet (11k) is connected to the hydrogen exhaust outlet of the fuel cell stack (4).

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