Fuel cell anode pressure control system and operation control method thereof

Abstract

The present invention provides a fuel cell anode pressure control system and its operation control method, wherein the fuel cell anode pressure control system includes a hydrogen supply device, at least one fuel cell stack and a system pressure regulating component. The hydrogen supply device is connected to the fuel cell stack, and the fuel cell stack has an air inlet end and a tail exhaust end, wherein the system pressure regulating component includes a pressure regulating valve, a pressure relief device and a tail exhaust valve, wherein the pressure regulating valve and the pressure relief device are arranged at the air inlet end of the fuel cell stack, and the pressure relief device is located between the pressure regulating valve and the air inlet end of the fuel cell stack, and the tail exhaust valve is arranged at the tail exhaust end of the fuel cell stack, wherein hydrogen is buffered in the pressure relief device from the hydrogen supply device through the pressure regulating valve, and then transported to the air inlet end of the fuel cell stack by the pressure relief device.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell anode pressure control system and an operation control method thereof. Background Art

[0002] A fuel cell is a device that can convert fuel and oxidants in the air into electrical energy through a chemical reaction. It is environmentally friendly and is an efficient power generation device. Its working environment is generally not higher than 100°C, and the product of the electrochemical reaction is liquid water.

[0003] As the temperature rises, some of the fuel cell reaction products transform into water vapor, while others transform into liquid water. These two forms of water are discharged to the outside world through the tailpipe valve at the rear of the fuel cell stack. The tailpipe valve also discharges some impurities produced by the fuel cell stack reaction. During tailpipe, at the moment of exhaust discharge, because the control target is pressure control, the hydrogen pressure entering the fuel cell stack reaches a high value. Fluctuations in hydrogen pressure can cause significant deviations in pressure control and lead to instability, easily resulting in pressure differentials outside the allowable range. This can seriously affect the fuel cell stack's service life and operational stability. When the stack experiences transient intake and exhaust, the inlet and outlet ports of the stack may differ significantly from the preset values, even exceeding the acceptable range, leading to unstable stack operation. In particular, when the fuel cell stack experiences sudden loading (current increase mode) and the pressure differential exceeds the set pressure differential range, or when the stack experiences sudden unloading (current reduction mode) and the pressure differential exceeds the set pressure differential range, the fuel cell stack may operate abnormally due to an imbalance in the supply to the anode supply system. Therefore, when the gas demand changes, there will be a large pressure difference between the gas inlet end of the fuel cell stack and the hydrogen pressure required by the system to set the fuel cell stack, which may even affect the normal use of the fuel cell stack.

[0004] The fuel cell system of the prior art, in particular the proton exchange membrane fuel cell, controls the pressure entering the stack and the actual pressure required by the stack to be approximately equal under different operating modes, so that the pressure difference between the required pressure and the actual pressure under different operating conditions can meet the operating conditions to the greatest extent. A proton exchange membrane fuel cell anode pressure control system and its working control method. Summary of the Invention

[0005] A major advantage of the present invention is that it provides a fuel cell anode pressure control system and an operating control method thereof, wherein the fuel cell anode pressure control system controls the pressure entering the stack and the actual pressure required by the stack under different operating modes to reduce the pressure difference between the required pressure and the actual pressure, which is beneficial to improving the operating stability of the fuel cell.

[0006] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and an operation control method thereof, wherein the fuel cell anode pressure control system includes a system pressure regulating component, wherein the system pressure regulating component is arranged on the anode side of the fuel cell, and is used to control the pressure difference between the required pressure and the actual pressure during the operation of the fuel cell.

[0007] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and an operation control method thereof, wherein the system pressure regulating component of the fuel cell anode pressure control system includes a pressure regulating valve, a buffer device and a tail exhaust valve, wherein the pressure regulating valve and the buffer device are arranged at the air inlet end of the fuel cell stack, and the tail exhaust valve is arranged at the tail exhaust end of the anode of the fuel cell stack, wherein the tail exhaust valve discharges in a time pulse, and the pressure regulating valve gives a duty cycle compensation before the tail exhaust valve discharges, and then cancels this duty cycle compensation before the tail exhaust valve finishes working to balance the fuel cell anode pressure difference and improve working stability.

[0008] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and an operation control method thereof, wherein when the pressure difference of the fuel cell stack suddenly loads (increase current mode) exceeds the set pressure difference range, the tail exhaust valve temporarily stops working outside the pressure difference range; or when the pressure difference of the fuel cell stack suddenly reduces load (reduce current mode) exceeds the set pressure difference range, the tail exhaust valve temporarily becomes linearly fully open outside the pressure difference range, which is beneficial to control the gas demand of the fuel cell stack and keep the pressure difference between the fuel cell stack inlet end and the hydrogen pressure required by the system for the fuel cell stack within a very small range within the set range.

[0009] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and its working control method, wherein the pressure regulating valve of the fuel cell anode pressure control system works together with the buffer device in a manner to compensate for the duty cycle in the discharge time relationship of the tail exhaust valve, so that the fluctuation range between the hydrogen pressure required by the stack inlet end and the system stack is reduced, and the pressure is within the set error range or the pressure between the two is closer.

[0010] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and an operating control method thereof, wherein the combined use of the pressure regulating valve, the buffer device and the tail exhaust valve of the fuel cell anode pressure control system ensures that the pressure fluctuation of the fuel cell stack intake pressure is small when the pressure regulating valve and the buffer tank are operating, which is conducive to accurately controlling the pressure or flow of the fuel gas entering the fuel cell stack.

[0011] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and an operating control method thereof, wherein the combined use of the pressure regulating valve, the buffer device and the tail exhaust valve of the fuel cell anode pressure control system ensures that the pressure of the fuel gas entering the fuel stack can quickly reach the pressure required by the fuel stack operating conditions under different operating conditions, thereby achieving faster and more efficient utilization of the fuel input to the fuel stack.

[0012] Another advantage of the present invention is that it provides a fuel cell anode pressure control system and its working control method, wherein the buffer device of the fuel cell anode pressure control system does not require any control and plays a storage and buffering role, is low in cost, safe and reliable. Therefore, the system has a simple structure, low cost, strong applicability, safety and reliability.

[0013] According to one aspect of the present invention, a fuel cell anode pressure control system of the present invention that can achieve the aforementioned objects and other objects and advantages includes:

[0014] a hydrogen supply device;

[0015] At least one fuel cell stack, wherein the hydrogen supply device is in communication with the fuel cell stack, and the fuel cell stack has an air inlet end and a tail end; and

[0016] A system pressure regulating component, wherein the system pressure regulating component includes a pressure regulating valve, a pressure relief device and a tail exhaust valve, wherein the pressure regulating valve and the pressure relief device are arranged at the air inlet end of the fuel cell stack, and the pressure relief device is located between the pressure regulating valve and the air inlet end of the fuel cell stack, and the tail exhaust valve is arranged at the tail exhaust end of the fuel cell stack, wherein hydrogen is buffered in the pressure relief device by the hydrogen supply device through the pressure regulating valve, and then transported to the air inlet end of the fuel cell stack by the pressure relief device.

[0017] According to one embodiment of the present invention, it further includes a system controller, wherein the system controller is electrically connected to the system pressure regulating component, and the system controller controls the working status of the pressure regulating valve and the tail exhaust valve, wherein the tail exhaust valve discharges the gas and water generated at the tail exhaust end of the fuel cell stack in a time pulse manner.

[0018] According to one embodiment of the present invention, the hydrogen supply device includes a hydrogen delivery pipeline, at least one control valve arranged on the hydrogen delivery pipeline, and a filtering device, wherein the hydrogen is delivered to the intake end of the fuel cell stack through the hydrogen delivery pipeline, the control valve and the filtering device.

[0019] According to one embodiment of the present invention, the system controller controls the pressure regulating valve and the tail exhaust valve of the system pressure regulating assembly to set a duty cycle compensation before discharge, and cancels the duty cycle compensation before the tail exhaust valve finishes working.

[0020] According to one embodiment of the present invention, when the fuel cell stack is suddenly loaded, the system controller controls the tail valve of the system pressure regulating assembly to temporarily stop working to reduce the pressure difference between the intake end of the fuel cell stack and the required hydrogen pressure set by the system.

[0021] According to one embodiment of the present invention, when the fuel cell stack is suddenly unloaded, the system controller controls the tail exhaust valve of the system pressure regulating assembly to be temporarily fully open.

[0022] According to one embodiment of the present invention, the system controller controls the pressure regulating valve to make a compensation duty cycle in the discharge time relationship of the tail exhaust valve, so that the pressure relief device buffers the hydrogen pressure to reduce the fluctuation range between the intake end of the fuel cell stack and the hydrogen pressure required by the system stack.

[0023] According to one embodiment of the present invention, the hydrogen pressure value required by the fuel cell stack is P-set, the pressure value at the front end of the fuel cell stack intake is Pq, the system allowable pressure difference value is P-safe, the tail exhaust time interval duration value of the tail exhaust valve is Tg and the tail exhaust time duration value is Tp; the duty cycle value of the system compensation of the pressure regulating valve when the tail exhaust valve is working in the tail exhaust is Pb, the system-given compensation duty cycle time value is Tb1, and the system-given cancellation compensation duty cycle time value is Tb2, wherein the system allowable pressure difference range value is P-safe>|P-set-Pq|>0, the system sets the compensation time value of the tail exhaust valve before opening to be Tbq1=Tg-Tb1, and Tb1≤Tg; the cancellation time value of the tail exhaust valve before closing is Tbq2=Tg+Tp-Tb2, and Tb2≤Tp.

[0024] According to one embodiment of the present invention, the compensation time value of the duty cycle value Pb of the pressure regulating valve compensation before the tail exhaust valve is opened is 0.

[0025] According to another aspect of the present invention, the present invention further provides an operation control method of a fuel cell anode pressure control system, wherein the operation control method comprises the following steps:

[0026] (a) buffering hydrogen gas to a pressure relief device, and then directing the pressure-relieved hydrogen gas to an inlet end of a fuel cell stack through the pressure relief device; and

[0027] (b) tail-discharging the exhaust gas and water generated by the fuel cell stack in a time pulse form.

[0028] According to one embodiment of the present invention, a pressure regulating valve is located at the air intake front end of the pressure relief device, and a tail exhaust valve is located at the tail exhaust end of the fuel cell stack. The pressure regulating valve loads a duty cycle compensation before the tail exhaust valve discharges, and cancels the duty cycle compensation before the tail exhaust valve ends.

[0029] According to one embodiment of the present invention, when the fuel cell stack is suddenly loaded (increase current mode), the tail exhaust valve is temporarily stopped; when the fuel cell stack is suddenly unloaded (reduce current mode), the tail exhaust valve is controlled to be fully open to control the gas demand of the stack and keep the pressure difference between the stack inlet end and the hydrogen pressure required by the system for the stack within a very small range within the set range.

[0030] According to one embodiment of the present invention, the hydrogen pressure value required by the fuel cell stack is P-set, the pressure value at the front end of the fuel cell stack intake is Pq, the system allowable pressure difference value is P-safe, the tail exhaust time interval duration value of the tail exhaust valve is Tg and the tail exhaust time duration value is Tp; the duty cycle value of the system compensation of the pressure regulating valve when the tail exhaust valve is working in the tail exhaust is Pb, the system-given compensation duty cycle time value is Tb1, and the system-given cancellation compensation duty cycle time value is Tb2, wherein the system allowable pressure difference range value is P-safe>|P-set-Pq|>0, the system sets the compensation time value of the tail exhaust valve before opening to be Tbq1=Tg-Tb1, and Tb1≤Tg; the cancellation time value of the tail exhaust valve before closing is Tbq2=Tg+Tp-Tb2, and Tb2≤Tp.

[0031] According to one embodiment of the present invention, the compensation time value of the duty cycle value Pb of the pressure regulating valve compensation before the tail exhaust valve is opened is 0.

[0032] Further objects and advantages of the present invention will be fully apparent from an understanding of the following description and accompanying drawings.

[0033] These and other objects, features and advantages of the present invention will be more fully understood from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1A 1 is a schematic diagram of the system composition of a fuel cell anode pressure control system according to a first preferred embodiment of the present invention.

[0035] Figure 1B 1 is a structural block diagram of the fuel cell anode pressure control system according to the first preferred embodiment of the present invention.

[0036] Figure 2It is a schematic diagram of pressure fluctuations on the anode side of a fuel cell during the operation of the fuel cell anode pressure control system according to the first preferred embodiment of the present invention and the prior art fuel cell anode pressure control system.

[0037] Figure 3 It is a schematic diagram of pressure fluctuations on the anode side of a fuel cell when the fuel cell anode pressure control system according to the first preferred embodiment of the present invention and the prior art fuel cell anode pressure control system are suddenly loaded / unloaded during operation.

[0038] Figure 4 2 is a schematic diagram of a working pressure control method of the fuel cell anode pressure control system according to the first preferred embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0040] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0041] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the elements may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0042] Referring to the accompanying drawings of the present invention Figures 1A to 4As shown, a fuel cell anode pressure control system and its working pressure control method according to the first preferred embodiment of the present invention are explained in the following description. The fuel cell anode pressure control system of this preferred embodiment of the present invention is suitable for the anode side of a proton membrane exchange fuel cell, wherein the fuel cell anode pressure control system is suitable for controlling the pressure entering the stack and the actual pressure required by the stack to be approximately equal under different working modes, so that the pressure difference between the required pressure and the actual pressure under different working conditions meets the use conditions to the greatest extent. The fuel cell anode pressure control system includes a hydrogen supply device 10, at least one fuel cell stack 20, a system pressure regulating component 30 arranged on the fuel cell stack 20, and a system controller 40, wherein the system pressure regulating component 30 is communicatively connected to the system controller 40, and the system controller 40 controls the working state of the system pressure regulating component to adjust the hydrogen supply strategy of the hydrogen supply device 10 to the fuel cell stack 20, so that the pressure entering the stack and the actual pressure required by the stack are accurately controlled to be approximately equal under different working modes.

[0043] In detail, the fuel cell stack 20 has an air inlet end and a tail exhaust end, wherein the system pressure regulating component 30 is arranged at the air inlet end and the tail exhaust end of the fuel cell stack 20, and the hydrogen supply device 10 is connected to the air inlet end of the fuel cell stack 20 through the system pressure regulating component 30, and the system pressure regulating component 30 controls the hydrogen supply device 10 to flow to the fuel cell stack 20.

[0044] The hydrogen supply device 10 includes a hydrogen delivery pipeline 11, at least one control valve 12 disposed on the hydrogen delivery pipeline 11, and a filter device 13, wherein the hydrogen is delivered to the intake end of the fuel cell stack 20 via the hydrogen delivery pipeline 11, the control valve 12, and the filter device 13. The control valve 12 controls the on / off of hydrogen delivery by the hydrogen delivery pipeline 11, and the filter device 13 filters impurities in the hydrogen delivery pipeline 11. The control valve 12 further includes a manual valve 121, a one-way valve 122, and a pressure reducing valve 123, wherein the manual valve 121 is suitable for manually adjusting the opening size of the hydrogen delivery pipeline 11, the one-way valve 122 prevents hydrogen backflow, and the pressure reducing valve 123 is used to control the pressure of the hydrogen in the hydrogen delivery pipeline 11.

[0045] Preferably, in this preferred embodiment of the present invention, the hydrogen supply device 10 further includes a hydrogen storage device 14, wherein the hydrogen storage device 14 is arranged at the front end of the hydrogen delivery pipeline 11, and hydrogen is stored in the hydrogen storage device 14 and delivered to the fuel cell stack through the hydrogen delivery pipeline 11.

[0046] Under the control of the system controller 40, the system pressure regulating assembly 30 controls the hydrogen supply device 10 to deliver hydrogen to the air inlet of the fuel cell stack 20, and controls the exhaust gas to be discharged from the exhaust end of the fuel cell stack 20. In other words, based on the control strategy set by the system controller 40, the system pressure regulating assembly 30 controls the fuel cell stack 20 to meet gas demand and maintain the pressure difference between the air inlet of the fuel cell stack 20 and the hydrogen pressure required by the system within a reasonable range.

[0047] The system pressure regulating assembly 30 includes a pressure regulating valve 31, a pressure relief device 32 and a tail exhaust valve 33, wherein the pressure regulating valve 31 and the pressure relief device 32 are arranged on the hydrogen delivery pipeline 11 of the hydrogen supply device 10, and the pressure regulating valve 31 and the pressure relief device 32 are located at the air inlet end of the fuel cell stack 20. The tail exhaust valve 33 is arranged at the tail exhaust end of the fuel cell stack 20. It is worth mentioning that in this preferred embodiment of the present invention, the fuel cell stack further includes a tail exhaust pipe, wherein the tail exhaust pipe is connected to the tail exhaust end of the fuel cell stack 20. The tail exhaust valve 33 is arranged on the tail exhaust pipe to control the fuel cell stack 20 to discharge exhaust gas outward.

[0048] It is worth mentioning that in this preferred embodiment of the present invention, along the direction of hydrogen delivery, the pressure regulating valve 31 is located at the front end of the pressure relief device 32, that is, the hydrogen passes through the pressure regulating valve 31 through the hydrogen delivery pipeline 11 and is buffered in the pressure relief device 32; the hydrogen buffered in the pressure relief device 32 is then passed through the hydrogen delivery pipeline 11 to the fuel cell stack 20. The exhaust gas after the reaction is discharged from the fuel cell stack 20 through the tail exhaust valve 33 from the tail exhaust end.

[0049] The pressure regulating valve 31 and the tail exhaust valve 33 of the system pressure regulating assembly 30 are controllably connected to the system controller 40, and the system controller 40 controls the working states of the pressure regulating valve 31 and the tail exhaust valve 33, thereby controlling the pressure or flow of the fuel gas entering the fuel cell stack. Preferably, in this preferred embodiment of the present invention, the pressure relief device 32 of the system pressure regulating assembly 30 is implemented as a buffer tank, wherein the buffer tank is conductively connected in series between the pressure regulating valve 31 and the fuel cell stack 20. Hydrogen is buffered in the pressure relief device 32 through the pressure regulating valve 31, and the buffered hydrogen is then passed to the inlet end of the fuel cell stack 20 through the pressure relief device 32. It is worth mentioning that the pressure relief device 32 can buffer the pressure changes caused by the hydrogen supply device 10 on the inlet end of the fuel cell stack 20 when the hydrogen supply suddenly increases or suddenly decreases. On the other hand, the pressure relief device 32 can also buffer the pressure change at the intake end of the fuel cell stack 20 when the fuel cell stack 20 is suddenly loaded (increase current mode) or suddenly unloaded (decrease current mode).

[0050] The system controller 40 can be implemented as a control unit independent of the fuel cell system, wherein the system controller 40 coordinates the air inlet end of the fuel cell stack and the system to set the hydrogen pressure required by the fuel cell stack, generates a control signal, and transmits the control signal to the pressure regulating valve 31 and the tail valve 33 of the system pressure regulating assembly 30. It is worth mentioning that the system controller 40 is electrically connected to the fuel cell stack 20, wherein the system controller 40 can set the hydrogen pressure required by the fuel cell stack 20. Preferably, in this preferred embodiment of the present invention, the system controller 40 is a control device of the fuel cell system, that is, the system controller 40 is integrated into the control module of the fuel cell system, wherein the system controller 40 is used to control the operation of the fuel cell.

[0051] In this preferred embodiment of the present invention, hydrogen is stored in the hydrogen storage device 14. The hydrogen passes through the hydrogen storage device 14, the hydrogen delivery pipeline 11, the manual valve 121, the filter device 13, the pressure reducing valve 123, the one-way valve 122, the pressure regulating valve 31, and the buffer device 32 to reach the inlet end of the fuel cell stack 20. The exhaust gas after the reaction of the fuel cell stack 20 is discharged from the tail end of the fuel cell stack 20 through the tail exhaust valve 33. The system controller 40 generates and formulates a corresponding control strategy based on the working requirements of the fuel cell stack 20. The system controller 40 coordinates the required hydrogen pressure set by the fuel cell stack 20 and the pressure formed by the system pressure regulating component 30 at the inlet end and the tail exhaust end of the fuel cell 20, so that under the control strategy set by the system controller 40, the inlet end of the fuel cell stack 20 and the hydrogen pressure value required by the system setting are close, that is, within a set error range, or the pressure difference fluctuation range between them is small.

[0052] It is worth mentioning that in this preferred embodiment of the present invention, the hydrogen is buffered by the pressure relief device 32 and then passed to the air inlet end of the fuel cell stack 20. The pressure relief effect of the pressure relief device 32 alleviates the change of the hydrogen pressure at the air inlet end of the fuel cell stack 20.

[0053] It is worth mentioning that in this preferred embodiment of the present invention, the system controller 40 controls the pressure regulating valve 31 and the tail exhaust valve 33 of the system pressure regulating assembly 30 based on the required hydrogen pressure set by the fuel cell stack 20, so as to achieve small fluctuations in the intake pressure of the fuel cell stack 20 when the pressure regulating valve 31 and the pressure relief device 32 are working at the tail exhaust valve 33, and accurately control the pressure or flow of the hydrogen gas entering the fuel cell stack 20. On the other hand, in this preferred embodiment of the present invention, the system controller 40 controls the pressure regulating valve 31 and the tail exhaust valve 33 of the system pressure regulating assembly 30 based on the required hydrogen pressure set by the fuel cell stack 20, so as to achieve that when the stack is in different working conditions, the pressure of the fuel gas entering the stack can quickly reach the pressure required for the working condition of the stack, thereby achieving faster and more efficient utilization of the fuel input to the stack.

[0054] It can be understood that in this preferred embodiment of the present application, the pressure relief device 32 buffers the hydrogen pressure between the fuel cell stack 20, and the pressure relief device 32 stores and buffers the hydrogen that has not entered the fuel cell stack 20 without the need for control, which is low cost, safe and reliable. Therefore, the system has a simple structure, low cost, strong applicability, and safety and reliability.

[0055] According to another aspect of the present invention, the operating control method of the fuel cell prototype pressure control system of this preferred embodiment of the present invention is explained in the following description. Hydrogen is provided by the hydrogen supply device 10 and buffered in the pressure relief device 32 via the pressure regulating valve 31 of the system pressure regulating assembly 30. The buffered hydrogen is then passed through the pressure relief device 32 to the fuel cell stack 20. During the reaction process in the fuel cell stack 20, tail gas and water are generated, which are discharged through the tail valve 33.

[0056] Preferably, in this preferred embodiment of the present invention, the tail exhaust valve 33 discharges tail exhaust gas and water in time pulses. The hydrogen pressure at the inlet end of the fuel cell stack 20 and the hydrogen pressure required by the system for the stack will instantaneously produce a large pressure difference. The system controller 40 controls the working state of the pressure regulating valve 31 and the tail exhaust valve 33 of the system pressure regulating assembly 30, sets a duty cycle compensation before the discharge, and cancels this duty cycle compensation before the tail exhaust valve 33 finishes working, so as to control the fuel cell stack 20 to maintain the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system within a reasonable range within the gas demand and the set range, that is, to reduce the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system.

[0057] When the fuel cell stack 20 is suddenly loaded, that is, the fuel cell system increases the current mode, and the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system exceeds the set pressure difference range, the system controller 40 controls the tail valve 33 of the system pressure regulating component 30 to temporarily stop working to reduce the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system. Conversely, when the fuel cell stack 20 is suddenly unloaded, that is, the fuel cell system reduces the current mode, and the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system exceeds the set pressure difference range, the system controller 40 controls the tail valve 33 of the system pressure regulating component 30 to temporarily be fully open, that is, the tail valve is in a linear fully open state, to control the stack in terms of gas demand and keep the pressure difference between the inlet end of the stack and the required hydrogen pressure set by the system within a very small range within the set range.

[0058] It is worth mentioning that in this preferred embodiment of the present invention, the system controller 40 controls the working states of the pressure regulating valve 31 and the tail exhaust valve 33 based on the set working pressure value, and combines the pressure relief device 32 to coordinate the stack inlet end and the system to set the hydrogen pressure required for the stack, so as to reduce the fluctuation of the stack inlet pressure, thereby accurately controlling the pressure or flow of the gas entering the stack.

[0059] When the system sets the pressure of hydrogen required by the fuel cell stack 20 to P-set, the system controller 40 controls the duty cycle of the pressure regulating valve 31 of the system pressure regulating assembly 30 to reach a certain opening based on the given pressure value P-set, so that the gas pressure at the intake end of the fuel cell stack 20 reaches the set value P-set in a short time. When the tail exhaust valve 33 reaches the pressure P-set, pulse discharge begins. At the moment of discharge of the tail exhaust valve 33, there is a deviation between the intake end of the fuel cell stack 20 and the hydrogen pressure required by the fuel cell stack 20. The system controller 40 compensates for the duty cycle by controlling the pressure regulating valve 31 in the discharge time relationship of the tail exhaust valve 33, and the pressure relief device 32 buffers the hydrogen pressure to reduce the fluctuation range between the intake end of the fuel cell stack 20 and the hydrogen pressure required by the system stack, so that the pressure is closer within the set error range or the pressure between the two is closer.

[0060] When the fuel cell stack 20 is in a sudden loading or sudden unloading mode, the hydrogen required by the fuel cell stack suddenly increases or suddenly decreases. The system controller 40 controls the tail valve 33 to be temporarily closed during sudden loading and to be linearly open during sudden unloading until the pressure returns to the set range.

[0061] The specific control steps of the fuel cell anode pressure control system and its operating pressure control method are as follows: assuming the required hydrogen pressure value of the fuel cell stack 20 is P-set, the pressure value at the intake front end of the fuel cell stack 20 is Pq, the system's allowable pressure differential value is P-safe, the tail drain time interval duration of the tail drain valve 33 is Tg, and the tail drain time duration is Tp; the system compensation duty cycle value of the pressure regulating valve 31 when the tail drain valve 33 is operating is Pb, the system-set compensation duty cycle time value is Tb1, and the system-set cancellation compensation duty cycle time value is Tb2. In this preferred embodiment of the present invention, the system's allowable pressure differential range is: P-safe > |P-set-Pq| > 0, the system sets the compensation time value before the tail drain valve 33 is opened to: Tbq1 = Tg - Tb1, with Tb1 ≤ Tg; and the cancellation time value before the tail drain valve 33 is closed is: Tbq2 = Tg + Tp - Tb2, with Tb2 ≤ Tp.

[0062] After the system sets P-set, the system controller 40 controls the working status of the pressure regulating valve 31 and the tail exhaust valve 33. When the front end pressure Pq of the fuel cell stack 20 quickly reaches the value of P-set and is balanced and adjusted, the fuel cell stack 20 consumes hydrogen at this time, and the tail exhaust valve 33 starts pulse adjustment at the time of Tg and Tp. Since the deviation between P-set and the inlet pressure Pq of the fuel cell stack 33 caused by the tail exhaust is greater than the allowable pressure difference range value set by the system, the system compensates the pressure regulating valve 31 with a duty cycle value Pb during the tail exhaust. This Pb value is given according to the working time of the tail exhaust valve 33.

[0063] Preferably, in this preferred embodiment of the present invention, the duty cycle value Pb of the pressure regulating valve 31 is compensated when the compensation time value before the tail exhaust valve 33 is opened is 0, that is, the duty cycle compensation Pb value starts to be given at the moment the tail exhaust valve 33 is opened. The time Tb2 for canceling the compensation Pb is set according to the time of the tail exhaust valve 33.

[0064] When the pressure at the front end of the fuel cell stack 20 fluctuates around the system set pressure P-set and is within the system allowable pressure differential P-safe, the fuel cell stack 20 is suddenly loaded, and the hydrogen demand of the fuel cell stack 20 increases, causing the pressure Pq to increase. After the system controller 40 sets P-set, it controls the system pressure regulating assembly 30 to quickly bring the pressure Pq at the front end of the fuel cell stack 20 close to the value of P-set and achieve balanced regulation. Since the system allowable pressure differential range is: P-safe < |P-set-Pq|, and the pressure Pq at the front end of the fuel cell stack 20 does not reach the system set pressure P-set at the moment of sudden loading, the tail drain valve 33 remains closed during the regulation process, ensuring that the pressure Pq at the front end of the fuel cell stack 20 quickly approaches the system set pressure P-set. When the pressure reaches the system allowable pressure differential range, the tail drain valve 33 pulses normally, and the system begins automatic regulation within the system allowable pressure differential P-safe. The compensation value and compensation time are as described above.

[0065] When the fuel cell stack 20 is suddenly unloaded, the hydrogen demand by the fuel cell stack 20 decreases, and the pressure Pq decreases. After the system sets a value P-set, the system controller 40 controls the system pressure regulating assembly 30, rapidly reducing the pressure Pq at the front end of the fuel cell stack 20 to near the value of P-set and balancing the pressure. Since the system allows a pressure differential range of P-safe < |P-set-Pq|, and the pressure Pq at the front end of the fuel cell stack 20 does not drop below the system set pressure value P-set during a sudden load reduction, the tailpipe valve 33 opens linearly during the regulation process, ensuring that the pressure Pq at the front end of the fuel cell stack 20 quickly approaches the system set pressure value P-set. Once the pressure differential reaches the system's allowable range, the tailpipe valve 33 pulses normally, and the system begins automatic regulation within the system's allowable pressure differential value P-safe. The compensation value and compensation time are as described above.

[0066] The following example further illustrates the beneficial effects of this preferred embodiment of the present invention. Under actual operating conditions, the pressure of the hydrogen storage device 14 is 1.5 MPa, which is reduced to 8 bar via a primary pressure reducing valve. The pressure regulating valve 31, with adjustable opening, is then controlled by the system controller 40 to fill the pressure relief device 32 and reach the fuel cell stack 20. Assuming the system's allowable pressure differential value, P-safe, is 0.02 bar, the adjustable pressure regulating valve is selected to have an opening of 5 bar or higher. The tail valve 33 is a solenoid valve capable of draining gas at a pressure of 8 bar or higher. Based on the actual operating conditions, a buffer tank of 1.6 L or higher is selected as the experimental pressure relief device 32.

[0067] like Figure 2As shown, first set the hydrogen pressure P-set required by the fuel cell stack 20 in experimental group 1 to 0.5 bar, the tail valve 33 working time interval Tg to 2000 ms, and the tail valve 33 working time duration Tp to 200 ms; set the hydrogen pressure P-set required by the fuel cell stack 20 in experimental group 2 to 0.8 bar, the tail valve 33 working time interval Tg to 10000 ms, and the tail valve 33 working time duration Tp to 400 ms; after the experimental group test process, we obtained a set of data: (1) When P-set = 0.5 bar, the system gives the compensation duty cycle time value Tb1 = 0, the system gives the cancellation compensation duty cycle time value Tb2 = 10, and the system compensation duty cycle value Pb = 40 (system duty cycle 0-1000); (2) When P-set = 0.8 bar When the system sets the compensation duty cycle time value Tb1 = 0, the system sets the cancellation compensation duty cycle time value Tb2 = 10, and the system compensation duty cycle value Pb = 70 (system duty cycle 0-1000). The experimental data shows that under different pressures and at different times, when the tail valve 33 operates, the pressure relief device 32 significantly reduces the pressure fluctuation range.

[0068] like Figure 3 As shown, based on the required hydrogen pressure P-set = 0.5 bar for the test stack, two sets of sudden load-on / load-off tests were conducted: the first set at P-set = 1.2 bar, and the second set at P-set = 1.6 bar. At these times, the tail drain valve 33 was set to operate for a time interval Tg = 2000 ms, a duration Tp = 200 ms, and a system-allowed pressure differential P-safe = 0.02 bar. During the sudden load event, P-set = 1.2 bar, and because P-safe = 0.02 bar < |P-set - Pq|, the stack front-end pressure Pq is far below P-set, so the tail drain valve 33 remains closed. After the system pressure is adjusted to P-safe = 0.02 bar > |P-set - Pq|, the tail drain valve 33 begins normal pulse discharge.

[0069] During a sudden load reduction, since P-safe = 0.02 bar < |P-set-Pq|, the stack front-end pressure Pq is significantly greater than P-set. Therefore, the tailpipe valve 33 opens linearly. When the system pressure is adjusted to P-safe = 0.02 bar > |P-set-Pq|, the tailpipe valve 33 begins normal pulse discharge. During a sudden load increase or decrease, P-set = 1.6 bar. Following the aforementioned operation for P-set = 1.2 bar, closed-loop testing shows that at pressures between 1.2 and 1.6 bar, the pressure control strategy adjusts the pressure back to a normal fluctuation range within 15-20 seconds, with pressure fluctuations within ±1 kPa, occasionally reaching ±1.5 kPa. Thus, the present invention improves upon existing technology by combining the pressure regulating valve 31, the pressure relief device 32, and the tailpipe valve 33 under the control of the system controller to reduce stack inlet pressure fluctuations during tailpipe valve 33 operation.

[0070] According to another aspect of the present invention, the present invention further provides a fuel cell anode pressure control method, wherein the fuel cell anode pressure control method comprises the following steps:

[0071] (a) buffering hydrogen gas to a pressure relief device 32, and then directing the pressure-relieved hydrogen gas to an inlet end of a fuel cell stack 20 through the pressure relief device 32; and

[0072] (b) exhausting the exhaust gas and water generated by the fuel cell stack 20 in a time pulse form.

[0073] According to the fuel cell anode pressure control system of the above-mentioned preferred embodiment of the present invention, in the steps of the working pressure control method of the present invention, a pressure regulating valve 31 is located at the air intake front end of the pressure relief device 32, and a tail exhaust valve 33 is located at the tail exhaust end of the fuel cell stack 20. The pressure regulating valve 31 loads a duty cycle compensation before the tail exhaust valve 33 is discharged, and cancels the duty cycle compensation before the tail exhaust valve 33 ends.

[0074] According to the fuel cell anode pressure control system of the above-mentioned preferred embodiment of the present invention, when the fuel cell stack 20 is suddenly loaded (increase current mode), the tail exhaust valve 33 is temporarily stopped from working; when the fuel cell stack 20 is suddenly unloaded (reduce current mode), the tail exhaust valve 33 is controlled to be fully open to control the gas demand of the stack and keep the pressure difference between the stack inlet end and the hydrogen pressure required by the system setting the stack within a very small range within the set range.

[0075] According to the fuel cell anode pressure control system of the preferred embodiment of the present invention, the operation control method of the preferred embodiment of the present invention further comprises the steps of:

[0076] The required hydrogen pressure P-set of the fuel cell stack 20 is set, and the duty cycle of the pressure regulating valve 31 is controlled to reach a certain opening by the set value P-set, so that the intake end of the fuel cell stack 20 reaches the set value, and when the tail exhaust end of the fuel cell stack 20 reaches the set value P-set, the tail exhaust valve 33 is controlled to pulse discharge.

[0077] At the moment of discharge, there is a deviation between the hydrogen pressure required by the fuel cell stack 20 and the intake end of the fuel cell stack 20. In the working control method of this preferred embodiment of the present invention, duty cycle compensation is made by controlling the discharge time relationship between the pressure regulating valve 31 and the tail exhaust valve 33, and the pressure relief device 32 buffers the hydrogen that does not enter the fuel cell stack 20, so that the fluctuation range between the intake end of the fuel cell stack 20 and the pressure required by the fuel cell stack 20 is reduced.

[0078] According to the fuel cell anode pressure control system of the preferred embodiment of the present invention, the required hydrogen pressure of the fuel cell stack 20 is P-set, the pressure at the intake front end of the fuel cell stack 20 is Pq, the system's allowable pressure differential is P-safe, the tail drain time interval of the tail drain valve 33 is Tg, and the tail drain time duration is Tp. The system's compensation duty cycle of the pressure regulating valve 31 when the tail drain valve 33 is operating is Pb, the system's set compensation duty cycle time is Tb1, and the system's set cancellation duty cycle time is Tb2. In this preferred embodiment of the present invention, the system's allowable pressure differential range is: P-safe > |P-set-Pq| > 0. The system sets the compensation time before opening the tail drain valve 33 to: Tbq1 = Tg - Tb1, with Tb1 ≤ Tg; and the cancellation time before closing the tail drain valve 33 is: Tbq2 = Tg + Tp - Tb2, with Tb2 ≤ Tp.

[0079] Preferably, in this preferred embodiment of the present invention, the duty cycle value Pb compensated by the pressure regulating valve 31 is 0 when the compensation time value before the tail exhaust valve 33 is opened, that is, the duty cycle compensation Pb value starts to be given at the moment the tail exhaust valve 33 is opened, and the effect is most obvious. The time Tb2 for canceling the compensation Pb is set according to the time of the tail exhaust valve 33.

[0080] Those skilled in the art will appreciate that the embodiments of the present invention described above and shown in the accompanying drawings are intended to be illustrative only and are not intended to limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and illustrated in the embodiments. Any variations or modifications may be made to the embodiments of the present invention without departing from the principles described.

Claims

1. A fuel cell anode pressure control system, characterized in that: include: a hydrogen supply device; At least one fuel cell stack, wherein the hydrogen supply device is in communication with the fuel cell stack, and the fuel cell stack has an air inlet end and a tail end; A system pressure regulating assembly, wherein the system pressure regulating assembly includes a pressure regulating valve, a pressure relief device, and a tail exhaust valve, wherein the pressure regulating valve and the pressure relief device are arranged at the air inlet end of the fuel cell stack, and the pressure relief device is located between the pressure regulating valve and the air inlet end of the fuel cell stack, and the tail exhaust valve is arranged at the tail exhaust end of the fuel cell stack, wherein hydrogen is supplied from the hydrogen supply device through the pressure regulating valve and buffered in the pressure relief device, and then transported by the pressure relief device to the air inlet end of the fuel cell stack; and a system controller, wherein the system controller is electrically connected to the system pressure regulating assembly, and the system controller controls the working states of the pressure regulating valve and the tail exhaust valve; The system controller controls the pressure regulating valve to compensate for the duty cycle in the discharge time relationship of the tail exhaust valve, and the pressure relief device buffers the hydrogen pressure to reduce the fluctuation range between the intake end of the fuel cell stack and the hydrogen pressure required by the system stack, wherein the hydrogen pressure required by the fuel cell stack is P-set, the pressure value at the intake front end of the fuel cell stack is Pq, the allowable pressure difference of the system is P-safe, the tail exhaust time interval duration of the tail exhaust valve is Tg, and the tail exhaust time duration is Tp; The duty cycle value of the system compensation of the pressure regulating valve when the tail exhaust valve is working in the tail exhaust is: Pb, the system-given compensation duty cycle time value is: Tb1, and the system-given cancellation compensation duty cycle time value is: Tb2, wherein the system allows the pressure difference range value: P-safe>|P-set-Pq|>0, and the system sets the compensation time value of the tail exhaust valve before opening to: Tbq1=Tg-Tb1, and Tb1≤Tg; the cancellation time value of the tail exhaust valve before closing is: Tbq2=Tg+Tp-Tb2, and Tb2≤Tp. 2 . The fuel cell anode pressure control system according to claim 1 , wherein the tail exhaust valve discharges the gas and water generated at the tail exhaust end of the fuel cell stack in a time pulse manner.

3. The fuel cell anode pressure control system according to claim 2, wherein the hydrogen supply device includes a hydrogen delivery pipeline, at least one control valve arranged on the hydrogen delivery pipeline, and a filtering device, wherein the hydrogen is delivered to the intake end of the fuel cell stack through the hydrogen delivery pipeline, the control valve and the filtering device.

4. The fuel cell anode pressure control system according to claim 2, wherein the system controller controls the pressure regulating valve and the tail exhaust valve of the system pressure regulating assembly to set a duty cycle compensation before discharge, and cancels the duty cycle compensation before the tail exhaust valve finishes working.

5. The fuel cell anode pressure control system according to claim 2, wherein when the fuel cell stack is suddenly loaded, the system controller controls the tail exhaust valve of the system pressure regulating assembly to temporarily stop working to reduce the pressure difference between the inlet end of the fuel cell stack and the required hydrogen pressure set by the system. 6 . The fuel cell anode pressure control system according to claim 2 , wherein when the fuel cell stack is suddenly unloaded, the system controller controls the tail exhaust valve of the system pressure regulating assembly to be temporarily fully open. 7 . The fuel cell anode pressure control system according to claim 1 , wherein the duty cycle value Pb of the pressure regulating valve compensation is 0 during the compensation time before the tail exhaust valve is opened.

8. A method for controlling an anode pressure control system of a fuel cell, characterized in that: The work control method comprises the following steps: a. buffering hydrogen gas to a pressure relief device, and then directing the pressure-relieved hydrogen gas to an air inlet of a fuel cell stack through the pressure relief device; and b. tail-discharging the exhaust gas and water generated by the fuel cell stack in the form of time pulses; One of the pressure regulating valves is located at the air inlet front end of the pressure relief device, and one of the tail exhaust valves is located at the tail exhaust end of the fuel cell stack. The pressure regulating valve loads a duty cycle compensation before the tail exhaust valve is discharged, and cancels the duty cycle compensation before the tail exhaust valve ends. The hydrogen pressure value required by the fuel cell stack is P-set, the pressure value at the air inlet front end of the fuel cell stack is: Pq, the system allowable pressure difference value is: P-safe, the tail exhaust time interval duration value of the tail exhaust valve is Tg, and the tail exhaust time duration value is Tp; the regulating valve The duty cycle value of the system compensation of the pressure valve when the tail exhaust valve is working in the tail exhaust is: Pb, the system-given compensation duty cycle time value is: Tb1, and the system-given cancellation compensation duty cycle time value is: Tb2, wherein the system allows the pressure difference range value: P-safe>|P-set-Pq|>0, and the system sets the compensation time value of the tail exhaust valve before opening to: Tbq1=Tg-Tb1, and Tb1≤Tg; the cancellation time value of the tail exhaust valve before closing is: Tbq2=Tg+Tp-Tb2, and Tb2≤Tp.

9. The working control method according to claim 8, wherein when the fuel cell stack is suddenly loaded, the tail exhaust valve is temporarily stopped to increase the current mode; when the fuel cell stack is suddenly unloaded, the tail exhaust valve is controlled to be fully open to reduce the current mode, so as to control the gas demand of the stack and keep the pressure difference between the stack inlet end and the hydrogen pressure required by the system setting the stack within a very small range within the set range. 10 . The working control method according to claim 8 , wherein the duty cycle value Pb of the pressure regulating valve compensation is 0 during the compensation time before the tail exhaust valve is opened.

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