Hydrogen flow control system of fuel cell and fuel cell system

Abstract

The utility model provides a hydrogen flow control system of a fuel cell and a fuel cell system, and the hydrogen flow control system of the fuel cell comprises a control module, an execution module used for controlling the hydrogen flow, and a driving module connected between the control module and the execution module, the acquisition module is connected with the control module and the driving module; a half-bridge driving circuit is arranged in the driving module, the half-bridge driving circuit comprises a first driving unit and a second driving unit, the first driving unit is connected between the first control end of the execution module and the control module, and the second driving unit is connected between the second control end of the execution module and the control module; a first acquisition circuit is arranged in the acquisition module, and the first acquisition circuit is connected between the first driving unit and the control module. According to the hydrogen flow control system of the fuel cell and the fuel cell system, the problem that in the prior art, a driving single end is prone to failure can be solved, and the stability of the fuel cell system can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel cells, in particular to a hydrogen flow control system of a fuel cell. Simultaneously, the utility model also relates to a fuel cell system provided with the hydrogen flow control system of the fuel cell. Background Art

[0002] Currently, the control of hydrogen flow control valves in fuel cell systems is primarily based on PID closed-loop control (proportional-integral-derivative control) based on the hydrogen inlet pressure. The drive circuits primarily utilize high-side or low-side drive to drive the flow control valve (including the electrical actuator module and valve) on and off. A few drive circuits also have current recovery control capabilities. However, these high- and low-side drive methods result in less precise control of the flow control valve and poor adaptability to changes in the valve's electrical parameters caused by high and low temperature environments. This translates to poor stability and makes single-ended failure of the high- and low-side drives more likely to occur, leading to serious failure of the hydrogen flow control valve. This failure can lead to serious consequences for the fuel cell system and compromises its safety and stability. Utility Model Content

[0003] In view of this, the present invention aims to provide a hydrogen flow control system for a fuel cell, so as to improve the safety and stability of the fuel cell system.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the utility model is achieved as follows:

[0005] A hydrogen flow control system for a fuel cell, comprising a control module, an execution module for controlling the hydrogen flow, a drive module connected between the control module and the execution module, and a collection module connected to both the control module and the drive module;

[0006] The driving module is provided with a half-bridge driving circuit, and the half-bridge driving circuit includes a first driving unit and a second driving unit, the first driving unit is connected between the first control terminal of the execution module and the control module, and the second driving unit is connected between the second control terminal of the execution module and the control module;

[0007] The acquisition module is provided with a first acquisition circuit for acquiring the current signal of the half-bridge drive circuit. The first acquisition circuit is connected between the first drive unit and the control module, or the first acquisition circuit is connected between the second drive unit and the control module.

[0008] Furthermore, the first driving unit includes a first MOS transistor, a first capacitor, a first resistor, a second resistor, and a third resistor; the drain of the first MOS transistor is connected to the first end of the first resistor, the gate of the first MOS transistor is connected to the second end of the first capacitor, the first end of the second resistor, and the first end of the third resistor, the source of the first MOS transistor is connected to the first control end of the execution module, the second end of the third resistor, and the ground end, the first end of the first capacitor is connected to the second end of the first resistor, and the second end of the second resistor is connected to the control module.

[0009] Furthermore, the first acquisition circuit is connected between the first drive unit and the control module; the first acquisition circuit includes a first isolation circuit, and an acquisition resistor connected to the control module through the first isolation circuit; the first end of the acquisition resistor is connected to the drain of the first MOS tube and the first end of the first resistor, and the second end of the acquisition resistor is connected to the power supply unit.

[0010] Furthermore, a first optocoupler isolation switch is provided in the first isolation circuit; the cathode of the first optocoupler isolation switch is connected to the first end of the collection resistor, the drain of the first MOS tube, and the first end of the first resistor, the anode of the first optocoupler isolation switch is connected to the second end of the collection resistor and the power supply unit, and the collector and emitter of the first optocoupler isolation switch are both connected to the control module.

[0011] Furthermore, the first acquisition circuit includes a first impedance matching circuit connected between the first optocoupler isolation switch and the control module, and the first impedance matching circuit includes a first operational amplifier, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor; the first input end of the first operational amplifier is connected to the collector of the first optocoupler isolation switch and the first end of the seventh resistor; the second input end of the first operational amplifier is connected to the emitter of the first optocoupler isolation switch and the second end of the seventh resistor through the eighth resistor, and the second input end of the first operational amplifier is connected to the first end of the ninth resistor; the output end of the first operational amplifier is connected to the control module, the second end of the ninth resistor, and the first end of the tenth resistor; the second end of the tenth resistor is connected to the ground end.

[0012] Furthermore, a diode and a third capacitor connected in series are connected between the source of the first MOS transistor and the first control terminal of the execution module, and a connection point between the diode and the third capacitor is connected to the ground terminal.

[0013] Furthermore, the second driving unit includes a second MOS transistor, a second capacitor, a fourth resistor, a fifth resistor, and a sixth resistor; the drain of the second MOS transistor is connected to the second control end of the execution module and the first end of the fourth resistor, the gate of the second MOS transistor is connected to the second end of the second capacitor, the first end of the fifth resistor, and the first end of the sixth resistor, the source of the second MOS transistor is connected to the second end of the sixth resistor and the ground end, the first end of the second capacitor is connected to the second end of the fourth resistor, and the second end of the fifth resistor is connected to the control module.

[0014] Furthermore, the acquisition module includes a second acquisition circuit for acquiring the voltage signal of the half-bridge drive circuit, the input end of the second acquisition circuit is connected to the first drive unit, the second drive unit, and the execution module in the half-bridge drive circuit, and the output end of the second acquisition circuit is connected to the control module.

[0015] Furthermore, the second acquisition circuit includes a second isolation circuit, in which a second optocoupler isolation switch is provided; the cathode of the second optocoupler isolation switch is connected to the drain of the second MOS tube, the first end of the fourth resistor, and the second control end of the execution module, the anode of the second optocoupler isolation switch is connected to the source of the first MOS tube, the second end of the third resistor, and the first control end of the execution module, the collector and emitter of the second optocoupler isolation switch are both connected to the control module, and / or a second impedance matching circuit is connected between the second optocoupler isolation switch and the control module.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The hydrogen flow control system of the fuel cell described in the present invention replaces the traditional high-side or low-side single-ended drive form with a half-bridge drive circuit, so that the two control ends of the execution module are respectively connected to the first drive unit and the second drive unit, and the current signal of the half-bridge drive circuit is collected by the first acquisition circuit. When the current signal of the half-bridge drive circuit is abnormal, that is, when one of the drive units fails, the other drive unit is used to drive the execution module to stop the hydrogen supply, so as to avoid the failure of the single-sided drive, thereby improving the safety and stability of the fuel cell system.

[0018] In addition, the first drive unit includes a first MOS tube, a first capacitor, a first resistor, a second resistor, and a third resistor. Not only is the structure simple and conducive to cost reduction, but the first drive unit can also have better stability by taking advantage of the characteristics of the MOS tube threshold voltage being relatively stable and not easily affected by temperature and voltage changes. The first acquisition circuit includes a first isolation circuit and an acquisition resistor connected to the control module through the first isolation circuit. Under the premise of facilitating current signal acquisition, electrical isolation transmission in the circuit can be achieved. The first isolation circuit is provided with a first optocoupler isolation switch, which can have a good signal isolation effect and strong anti-interference performance, which is conducive to improving the stability of the circuit operation.

[0019] Secondly, the provision of the first impedance matching circuit can optimize signal transmission quality and help ensure that the collected current signal is transmitted to the control module. A diode and a third capacitor are connected in series between the source of the first MOS tube and the first control terminal of the execution module, and the connection point between the diode and the third capacitor is connected to the ground terminal, which is conducive to achieving the freewheeling effect of the circuit. The second drive unit includes a second MOS tube, a fourth resistor, a fifth resistor, and a sixth resistor. Similarly, under the premise of achieving a simple structure and reducing costs, it can take advantage of the characteristics of the MOS tube threshold voltage being relatively stable and not easily affected by temperature and voltage changes to make the second drive unit have better stability.

[0020] Furthermore, a second acquisition circuit for collecting the voltage signal from the half-bridge drive circuit facilitates collaboration with the two drive units and the control module to detect the operating status of the execution module. This second acquisition circuit includes a second isolation circuit, which is equipped with a second optocoupler isolation switch, enhancing the circuit's signal isolation, improving its anti-interference performance, and improving its operational stability.

[0021] Another object of the present invention is to provide a fuel cell system, wherein the fuel cell system is provided with the hydrogen flow control system of the fuel cell as described above.

[0022] The fuel cell system described in the present invention is provided with the above-mentioned fuel cell hydrogen flow control system, which can reduce the risk of single-end drive failure compared to traditional high-side drive or low-side drive forms, and is beneficial to improving the safety and stability of the fuel cell system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0024] Figure 1This is a structural block diagram of the hydrogen flow control system of the fuel cell according to an embodiment of the present utility model;

[0025] Figure 2 This is a circuit schematic diagram of a hydrogen flow control system for a fuel cell according to an embodiment of the present utility model;

[0026] Description of reference numerals:

[0027] 1. Control module; 2. Execution module; 3. Drive module; 4. Acquisition module;

[0028] Q1, first MOS transistor; Q2, second MOS transistor; U1, first optocoupler isolation switch; U2, second optocoupler isolation switch; CF1, first operational amplifier; CF2, second operational amplifier; C1, first capacitor; C2, second capacitor; C3, third capacitor; D1, diode; VBAT, power supply unit; Rsh, acquisition resistor;

[0029] R1, the first resistor; R2, the second resistor; R3, the third resistor; R4, the fourth resistor; R5, the fifth resistor; R6, the sixth resistor; R7, the seventh resistor; R8, the eighth resistor; R9, the ninth resistor; R10, the tenth resistor; R11, the eleventh resistor; R12, the twelfth resistor; R13, the thirteenth resistor; R14, the fourteenth resistor. DETAILED DESCRIPTION

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0031] In the following description, specific details such as specific system structures and techniques are provided for purposes of illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obscuring the description of the present application with unnecessary detail.

[0032] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," and "outer" appear to indicate orientation or positional relationships, these are based on the orientation or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, if terms such as "first" and "second" appear, they are used solely for descriptive purposes and should not be construed as indicating or implying relative importance.

[0033] Furthermore, in the description of this utility model, unless otherwise explicitly defined, the terms "mounted," "connected," "connection," and "connector" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0034] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0035] Example 1

[0036] This embodiment relates to a hydrogen flow control system for a fuel cell, which can solve the problem of single-end failure of the drive that is prone to occur in traditional technologies using high-side drive or low-side drive, and is conducive to improving the stability and reliability of the drive.

[0037] In terms of overall design, Figure 1 and Figure 2 As shown, the hydrogen flow control system of the fuel cell in this embodiment includes a control module 1, an execution module 2 for controlling the hydrogen flow rate, a driving module 3 connected between the control module 1 and the execution module 2, and a collection module 4 connected to both the control module 1 and the driving module 3.

[0038] In addition, a half-bridge driving circuit is provided in the driving module 3, and the half-bridge driving circuit includes a first driving unit and a second driving unit. The first driving unit is connected between the first control end of the execution module 2 and the control module 1, and the second driving unit is connected between the second control end of the execution module 2 and the control module 1.

[0039] At the same time, the acquisition module 4 is provided with a first acquisition circuit for acquiring the current signal of the half-bridge drive circuit. The first acquisition circuit is connected between the first drive unit and the control module 1, or the first acquisition circuit is connected between the second drive unit and the control module 1.

[0040] At this time, as set above, a half-bridge drive circuit can be used to replace the traditional high-side or low-side single-ended drive form, so that the two control ends of the execution module 2 are respectively connected to the first drive unit and the second drive unit, and the current signal of the half-bridge drive circuit is collected by the first acquisition circuit. When the current signal of the half-bridge drive circuit is abnormal, that is, when one of the drive units fails, the other drive unit can be used to drive the execution module 2 to stop the hydrogen supply, so as to avoid the failure of the unilateral drive, thereby improving the safety and stability of the fuel cell system.

[0041] Based on the above overview, in detail, in this embodiment, during implementation, control module 1 can employ a controller familiar to those skilled in the art, such as an MCU. Execution module 2 can be an electric actuator in a control valve, such as a flow control valve or a solenoid valve, as is familiar to those skilled in the art. Furthermore, this embodiment can employ current-based PID control, also known to those skilled in the art, to implement the entire control process from acquisition module 4 to control module 1 to drive module 3 to execution module 2.

[0042] Furthermore, in this embodiment, as a preferred implementation form, Figure 2 As shown, the first driving unit includes a first MOS transistor Q1, a first capacitor C1, a first resistor R1, a second resistor R2, and a third resistor R3. The drain of the first MOS transistor Q1 is connected to the first end of the first resistor R1, the gate of the first MOS transistor Q1 is connected to the second end of the first capacitor C1, the first end of the second resistor R2, and the first end of the third resistor R3, the source of the first MOS transistor Q1 is connected to the first control end of the execution module 2, the second end of the third resistor R3, and the ground end, the first end of the first capacitor C1 is connected to the second end of the first resistor R1, and the second end of the second resistor R2 is connected to the control module 1.

[0043] The main advantage of such a setting is that it not only has a simple structure and is conducive to cost reduction, but also can make use of the characteristics of the MOS tube threshold voltage being relatively stable and not easily affected by temperature and voltage changes to make the first driving unit have better stability.

[0044] Secondly, as a preferred implementation, in this embodiment, a first acquisition circuit is connected between the first drive unit and the control module 1. The first acquisition circuit includes a first isolation circuit and an acquisition resistor Rsh connected to the control module 1 via the first isolation circuit. Specifically, the first end of the acquisition resistor Rsh is connected to the drain of the first MOS transistor Q1 and the first end of the first resistor R1, and the second end of the acquisition resistor Rsh is connected to the power supply unit VBAT. This facilitates current signal acquisition while achieving electrical isolation and transmission within the circuit.

[0045] Considering the stability of the first isolation circuit, in this embodiment, as a preferred implementation form, a first optocoupler isolation switch U1 is provided in the first isolation circuit. Furthermore, the cathode of the first optocoupler isolation switch U1 is connected to the first end of the acquisition resistor Rsh, the drain of the first MOS transistor Q1, and the first end of the first resistor R1. The anode of the first optocoupler isolation switch U1 is connected to the second end of the acquisition resistor Rsh and the power supply unit VBAT. The collector and emitter of the first optocoupler isolation switch U1 are both connected to the control module 1. The main benefit of this arrangement is that, based on the characteristics of the first optocoupler isolation switch U1, the circuit can have a good signal isolation effect and strong anti-interference performance, thereby facilitating the improvement of the circuit's operating stability.

[0046] The power supply unit VBAT here can adopt a 24V power supply commonly used by those skilled in the art to ensure normal operation of the circuit. Of course, the power supply unit VBAT can also adopt other types of power supplies, such as a 12V power supply, according to actual application requirements or application environment.

[0047] Furthermore, in this embodiment, as a preferred implementation form, the first acquisition circuit includes a first impedance matching circuit connected between the first optocoupler isolation switch U1 and the control module 1. In specific settings, the first impedance matching circuit includes a first operational amplifier CF1, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9 and a tenth resistor R10.

[0048] The first input end of the first operational amplifier CF1 is connected to the collector of the first optocoupler isolation switch U1 and the first end of the seventh resistor R7. The second input end of the first operational amplifier CF1 is connected to the emitter of the first optocoupler isolation switch U1 and the second end of the seventh resistor R7 via the eighth resistor R8. The second input end of the first operational amplifier CF1 is connected to the first end of the ninth resistor R9. The output end of the first operational amplifier CF1 is connected to the control module 1, the second end of the ninth resistor R9, and the first end of the tenth resistor R10. The second end of the tenth resistor R10 is connected to ground.

[0049] It can be understood that, based on the setting of the first impedance matching circuit, the signal transmission quality can be optimized, which helps to ensure that the collected current signal is transmitted to the control module 1.

[0050] In addition, in this embodiment, as a preferred embodiment, continue to refer to Figure 2 As shown in FIG, a diode D1 and a third capacitor C3 are connected in series between the source of the first MOS transistor Q1 and the first control terminal of the execution module 2, and the connection point between the diode D1 and the third capacitor C3 is connected to the ground terminal. This facilitates the freewheeling function of the circuit.

[0051] In addition, in this embodiment, as a preferred implementation form, refer again to Figure 2 As shown, the second driving unit includes a second MOS transistor Q2, a second capacitor C2, a fourth resistor R4, a fifth resistor R5 and a sixth resistor R6.

[0052] The drain of the second MOS transistor Q2 is connected to the second control terminal of the execution module 2 and the first end of the fourth resistor R4; the gate of the second MOS transistor Q2 is connected to the second end of the second capacitor C2, the first end of the fifth resistor R5, and the first end of the sixth resistor R6; the source of the second MOS transistor Q2 is connected to the second end of the sixth resistor R6 and the ground terminal; the first end of the second capacitor C2 is connected to the second end of the fourth resistor R4; and the second end of the fifth resistor R5 is connected to the control module 1.

[0053] It can be understood that the second driving unit includes a second MOS transistor Q2, a second capacitor C2, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6. Similar to the first driving unit, the second driving unit can also have better stability while achieving a simple structure and reducing costs by utilizing the characteristics that the threshold voltage of the MOS transistor is relatively stable and not easily affected by temperature and voltage changes.

[0054] In a specific implementation, the diode D1 of this embodiment can be a Zener diode, and the cathode of the Zener diode is respectively connected to the source of the first MOS transistor Q1, the second end of the third resistor R3, the first control end of the execution module 2, the drain of the second MOS transistor Q2, and the second end of the third capacitor C3, and the anode of the Zener diode is connected to the first end of the third capacitor C3 and the ground line to achieve the purpose of freewheeling in the circuit.

[0055] In addition, in this embodiment, as a preferred implementation, the acquisition module includes a second acquisition circuit for acquiring the voltage signal of the half-bridge drive circuit. The input of the second acquisition circuit is connected to the first and second drive units in the half-bridge drive circuit, as well as the execution module 2, and the output of the second acquisition circuit is connected to the control module 1. This configuration facilitates the cooperation between the second acquisition circuit, the two drive units, and the control module 1 to detect the operating status of the execution module 2.

[0056] It is worth mentioning that in conventional technologies using high-side or low-side drive, valve failure can only be detected by disassembly and inspection, which affects the use and maintenance of the fuel cell system. The purpose of providing a second acquisition circuit is to solve the problem of conventional technology that cannot diagnose the valve (specifically, the execution module 2 in this embodiment, that is, the electric actuator connected to the valve) and avoid valve failure causing fuel cell system failure.

[0057] Specifically, in this embodiment, as a preferred implementation form, the second acquisition circuit includes a second isolation circuit, in which a second optocoupler isolation switch U2 is provided. The cathode of the second optocoupler isolation switch U2 is connected to the drain of the second MOS transistor Q2, the first end of the fourth resistor R4, and the second control terminal of the execution module 2. The anode of the second optocoupler isolation switch U2 is connected to the source of the first MOS transistor Q1, the second end of the third resistor R3, and the first control terminal of the execution module 2. The collector and emitter of the second optocoupler isolation switch U2 are both connected to the control module 1. The main benefit of this arrangement is that it can enhance the signal isolation effect of the circuit, making the circuit have better anti-interference performance and facilitating improved circuit operating stability.

[0058] Similarly, as a preferred implementation form, a second impedance matching circuit is connected between the second optocoupler isolation switch U2 and the control module 1 in this embodiment to optimize the signal transmission quality and ensure that the collected current signal is transmitted to the control module 1.

[0059] In a specific configuration, the second impedance matching circuit includes a second operational amplifier CF2, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, and a fourteenth resistor R14. The first input end of the second operational amplifier CF2 is respectively connected to the collector of the second optocoupler isolation switch U2 and the first end of the eleventh resistor R11. The second input end of the second operational amplifier CF2 is respectively connected to the emitter of the second optocoupler isolation switch U2 and the second end of the eleventh resistor R11 through the twelfth resistor R12, and the second input end of the second operational amplifier CF2 is connected to the first end of the thirteenth resistor R13. The output end of the second operational amplifier CF2 is respectively connected to the control module 1, the second end of the thirteenth resistor R13, and the first end of the fourteenth resistor R14. The second end of the fourteenth resistor R14 is grounded.

[0060] It is worth noting that the first MOS transistor Q1 and the second MOS transistor Q2 in this embodiment can both be MOS transistors well known to those skilled in the art. Specifically, the full name of a MOS transistor is MOSFET (Metal Oxide Semiconductor Field Effect Transistor). Furthermore, the first operational amplifier CF1 and the second operational amplifier CF2 in this embodiment can preferably be virtual operational amplifiers, and the first optocoupler isolation switch U1 and the second optocoupler isolation switch U2 can also be electronic components well known to those skilled in the art, and will not be further described here.

[0061] In this embodiment, combined with Figure 1 and Figure 2As shown, one control logic of the hydrogen flow control system of the fuel cell is as follows:

[0062] The control module (e.g., MCU) outputs control commands to Q1 and Q2 of the half-bridge drive circuit based on the operating logic of the fuel cell system. Q1 and Q2 are turned on and off according to the output frequency and duty cycle of the MCU to drive the execution module 2 (the execution module 2 can be, for example, an electric actuator in a flow control valve, represented by FIV in the circuit diagram). Subsequently, when the FIV is open, the half-bridge drive current is collected through the acquisition resistor Rsh (which is a high-precision sampling resistor). This drive current is the current I flowing through the flow control valve. Rsh ; The current of the collection resistor Rsh generates a voltage drop after passing through the collection resistor Rsh. The magnitude of the voltage drop is U Rsh =Rsh*I Rsh ;U Rsh After passing through the first optocoupler isolation analog switch U1, it is input to the input end of the first impedance matching circuit.

[0063] The voltage input to the impedance matching circuit is proportionally calculated by the first operational amplifier CF1, generating a voltage within the voltage range received by control module 1. Control module 1 then collects this voltage and divides it by the proportional op amp factor and Rsh to obtain the actual current of the half-bridge drive circuit. Finally, the MCU performs PID control on the collected current and the target current, outputting control commands to the half-bridge drive circuit to implement closed-loop current control of the FIV (e.g., the electric actuator in a flow control valve). This current-based control phase primarily aims to ensure that if either the first or second drive unit in the half-bridge drive circuit fails, the other normally functioning drive unit can drive the valve to close. For example, by driving actuator module 2 (e.g., the electric actuator in the flow control valve), the specific valve structure (e.g., the valve connected to the electric actuator in the flow control valve) is closed.

[0064] The hydrogen flow control system of the fuel cell can also diagnose the flow control valve. The control logic is as follows:

[0065] The second acquisition circuit can collect the voltage between the upper and lower bridges (the first drive unit and the second drive unit) of the half-bridge drive circuit, that is, the voltage across the execution module 2 (for example, the electric actuator in the flow control valve) can be collected. The collected voltage is input to the input end of the second impedance matching circuit after passing through the second optically coupled isolation analog switch U2. Subsequently, the voltage input to the impedance matching circuit is proportionally calculated by the second operational amplifier CF2 to generate a voltage suitable for the voltage range received by the control module 1. This voltage is the voltage across the electric actuator in the flow control valve, for example, divided by I RshThe impedance of the execution module 2 can be obtained. This impedance is composed of the inductive reactance and the resistance of the execution module 2. By comparing the collected impedance with the design impedance of the execution module 2, it can be determined whether the electrical parameters of the execution module exceed the design value. If they exceed the design value, it can be determined that the execution module 2 is aged or damaged and needs to be replaced.

[0066] The hydrogen flow control system of the fuel cell of this embodiment replaces the traditional high-side or low-side single-ended drive form with a half-bridge drive circuit, so that the two control ends of the execution module 2 are respectively connected to the first drive unit and the second drive unit, and the current signal of the half-bridge drive circuit is collected by the first acquisition circuit. When the current signal of the half-bridge drive circuit is abnormal, that is, when one of the drive units fails, the other drive unit can be used to drive the execution module 2 to stop the hydrogen supply, so as to avoid the failure of the single-sided drive, thereby improving the safety and stability of the fuel cell system.

[0067] At the same time, the hydrogen flow control system of the fuel cell can realize the online diagnosis function of the execution module 2 on the basis of solving the problem that the high and low side drive forms in the existing technology are prone to unilateral failure, which is more conducive to improving the quality of the fuel cell system.

[0068] Example 2

[0069] This embodiment relates to a fuel cell system, in which the hydrogen flow control system of the fuel cell in the first embodiment is provided.

[0070] The fuel cell system of this embodiment, by configuring the hydrogen flow control system of the fuel cell in Example 1, can replace the high-side drive or low-side drive form in traditional technology, and has higher drive reliability, which is conducive to solving the problem of single-end drive failure, thereby helping to improve the safety and stability of the fuel cell system.

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A hydrogen flow control system for a fuel cell, characterized in that: It comprises a control module (1), an execution module (2) for controlling the flow rate of hydrogen, a drive module (3) connected between the control module (1) and the execution module (2), and a collection module (4) connected to both the control module (1) and the drive module (3); The driving module (3) is provided with a half-bridge driving circuit, the half-bridge driving circuit comprising a first driving unit and a second driving unit, the first driving unit being connected between the first control end of the execution module (2) and the control module (1), and the second driving unit being connected between the second control end of the execution module (2) and the control module (1); The acquisition module (4) is provided with a first acquisition circuit for acquiring the current signal of the half-bridge drive circuit, the first acquisition circuit being connected between the first drive unit and the control module (1), or the first acquisition circuit being connected between the second drive unit and the control module (1).

2. The hydrogen flow control system for a fuel cell according to claim 1, characterized in that: The first driving unit comprises a first MOS tube (Q1), a first capacitor (C1), a first resistor (R1), a second resistor (R2) and a third resistor (R3); The drain of the first MOS tube (Q1) is connected to the first end of the first resistor (R1), the gate of the first MOS tube (Q1) is connected to the second end of the first capacitor (C1), the first end of the second resistor (R2), and the first end of the third resistor (R3), the source of the first MOS tube (Q1) is connected to the first control end of the execution module (2), the second end of the third resistor (R3), and the ground end, the first end of the first capacitor (C1) is connected to the second end of the first resistor (R1), and the second end of the second resistor (R2) is connected to the control module (1).

3. The hydrogen flow control system for a fuel cell according to claim 2, characterized in that: The first acquisition circuit is connected between the first drive unit and the control module (1); The first acquisition circuit comprises a first isolation circuit and an acquisition resistor connected to the control module (1) via the first isolation circuit; A first end of the acquisition resistor (Rsh) is connected to the drain of the first MOS tube (Q1) and a first end of the first resistor (R1), and a second end of the acquisition resistor (Rsh) is connected to a power supply unit (VBAT).

4. The hydrogen flow control system for a fuel cell according to claim 3, characterized in that: A first optocoupler isolation switch (U1) is provided in the first isolation circuit; The cathode of the first optocoupler isolation switch (U1) is connected to the first end of the acquisition resistor (Rsh), the drain of the first MOS tube (Q1), and the first end of the first resistor (R1); the anode of the first optocoupler isolation switch (U1) is connected to the second end of the acquisition resistor (Rsh) and the power supply unit (VBAT); and the collector and emitter of the first optocoupler isolation switch (U1) are both connected to the control module (1).

5. The hydrogen flow control system for a fuel cell according to claim 4, characterized in that: The first acquisition circuit comprises a first impedance matching circuit connected between the first optical coupler isolation switch (U1) and the control module (1), the first impedance matching circuit comprising a first operational amplifier (CF1), a seventh resistor (R7), an eighth resistor (R8), a ninth resistor (R9) and a tenth resistor (R10); The first input terminal of the first operational amplifier (CF1) is connected to the collector of the first optical coupling isolation switch (U1) and the first end of the seventh resistor (R7); The second input end of the first operational amplifier (CF1) is connected to the emitter of the first optical coupling isolation switch (U1) and the second end of the seventh resistor (R7) through the eighth resistor (R8), and the second input end of the first operational amplifier (CF1) is connected to the first end of the ninth resistor (R9); The output end of the first operational amplifier (CF1) is connected to the control module (1), the second end of the ninth resistor (R9), and the first end of the tenth resistor (R10); The second end of the tenth resistor (R10) is connected to the ground end.

6. The hydrogen flow control system for a fuel cell according to claim 2, characterized in that: A diode (D1) and a third capacitor (C3) connected in series are connected between the source of the first MOS tube (Q1) and the first control end of the execution module (2), and the connection point between the diode (D1) and the third capacitor (C3) is connected to the ground end.

7. The hydrogen flow control system for a fuel cell according to any one of claims 2 to 6, characterized in that: The second driving unit comprises a second MOS tube (Q2), a second capacitor (C2), a fourth resistor (R4), a fifth resistor (R5) and a sixth resistor (R6); The drain of the second MOS tube (Q2) is connected to the second control end of the execution module (2) and the first end of the fourth resistor (R4); the gate of the second MOS tube (Q2) is connected to the second end of the second capacitor (C2), the first end of the fifth resistor (R5), and the first end of the sixth resistor (R6); the source of the second MOS tube (Q2) is connected to the second end of the sixth resistor (R6) and the ground end; the first end of the second capacitor (C2) is connected to the second end of the fourth resistor (R4); and the second end of the fifth resistor (R5) is connected to the control module (1).

8. The hydrogen flow control system for a fuel cell according to claim 7, characterized in that: The acquisition module (4) comprises a second acquisition circuit for acquiring the voltage signal of the half-bridge drive circuit, the input end of the second acquisition circuit being connected to the first drive unit, the second drive unit, and the execution module (2) in the half-bridge drive circuit, and the output end of the second acquisition circuit being connected to the control module (1).

9. The hydrogen flow control system for a fuel cell according to claim 8, characterized in that: The second acquisition circuit includes a second isolation circuit, in which a second optocoupler isolation switch (U2) is provided; The cathode of the second optocoupler isolation switch (U2) is connected to the drain of the second MOS tube (Q2), the first end of the fourth resistor (R4), and the second control end of the execution module (2); the anode of the second optocoupler isolation switch (U2) is connected to the source of the first MOS tube (Q1), the second end of the third resistor (R3), and the first control end of the execution module (2); the collector and emitter of the second optocoupler isolation switch (U2) are both connected to the control module (1); and / or a second impedance matching circuit is connected between the second optocoupler isolation switch (U2) and the control module (1).

10. A fuel cell system, characterized in that: The fuel cell system is provided with a hydrogen flow control system for the fuel cell according to any one of claims 1 to 9.

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