A purge control system and method for a commercial vehicle hydrogen fuel cell stack

Abstract

The present invention provides a purge control system and method for a commercial vehicle hydrogen fuel cell stack. The method includes: providing a first purge pipe so that the output pipeline of the air compressor is connected to the purge port of the stack through the first purge pipe, and a one-way valve is provided on the first purge pipe; providing a second purge pipe so that the brake air source is connected to the purge port of the stack through the second purge pipe, and a low-pressure purge valve is provided on the second purge pipe to obtain the insulation resistance of the stack; when the insulation resistance of the stack is less than a first set threshold, the vehicle controller controls the low-pressure purge valve to be turned on, so that the brake air source purges the interior of the stack through the second purge pipe until the insulation resistance of the stack reaches a second set threshold. When the insulation resistance of the stack is greater than the second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the stack through the first purge pipe. The present invention can improve user convenience and safety.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel cell stack purge control, and in particular to a purge control system and method for a commercial vehicle hydrogen fuel cell stack. Background Art

[0002] Existing hydrogen fuel cell commercial vehicles use dry air from an air compressor to purge water vapor and other suspended gases from the fuel cell stack. This prevents the gases from forming a conductor and reducing the insulation resistance within the stack. If the insulation resistance is too low, the vehicle controller will determine that the insulation resistance is too low and there is a risk of leakage, and will cut off the high-voltage power supply to the vehicle to ensure safe use. In southern China, if the fuel cell stack has not been used for a long time or has experienced rainy weather, the air inside the stack will also be relatively humid. This humid air reduces the insulation resistance of the stack, making it impossible for the vehicle to use high-voltage power. Because the high-voltage power supply cannot be started, the air compressor cannot purge the interior of the fuel cell stack, causing the vehicle to fail to start and requiring after-sales service. Therefore, how to control the purge of the fuel cell stack to improve user convenience and safety is of great significance. Summary of the Invention

[0003] The present invention provides a purge control system and method for a hydrogen fuel cell stack of a commercial vehicle, which solves the problem that the air compressor of the hydrogen fuel cell stack of an existing commercial vehicle is unable to purge the inside of the stack in a humid environment, thereby preventing the vehicle from starting. The system can improve the convenience and safety of user use.

[0004] To achieve the above objectives, the present invention provides the following technical solutions:

[0005] A purge control system for a hydrogen fuel cell stack of a commercial vehicle, comprising: a vehicle controller, a stack inspection device, an air compressor, a brake air source, a low-pressure purge valve, and a one-way valve;

[0006] The output pipeline of the air compressor is connected to the purge port of the fuel cell stack through a first purge pipe, and the first purge pipe is provided with the one-way valve;

[0007] The brake air source is connected to the purge port of the fuel cell stack through a second purge pipe, and the second purge pipe is provided with the low-pressure purge valve;

[0008] The vehicle controller is respectively connected to the stack inspection device, the air compressor and the low-pressure purge valve signal;

[0009] The stack inspection device is used to detect the insulation resistance of the stack and feed back the insulation resistance status of the stack to the vehicle controller;

[0010] The vehicle controller controls the low-pressure purge valve to be turned on when the insulation resistance of the fuel cell stack is less than a first set threshold value, so that the brake air source purges the interior of the fuel cell stack through the second purge pipe until the insulation resistance of the fuel cell stack reaches the second set threshold value;

[0011] When the insulation resistance of the fuel cell stack rises to a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

[0012] Preferably, it also includes: an ignition switch;

[0013] The ignition switch is respectively connected to the vehicle controller and the stack inspection device by signal. When the ignition switch is in the IG position, the vehicle is started at low voltage to supply power to the vehicle controller and the stack inspection device.

[0014] The vehicle controller controls the high-voltage power supply of the vehicle to be turned on when the ignition switch is in the ON position and the insulation resistance of the battery stack is greater than the second set threshold.

[0015] Preferably, after the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started. If so, it controls the air compressor to start to purge the inside of the fuel cell stack.

[0016] Preferably, it also includes: instruments;

[0017] The instrument is connected to the vehicle controller signal, and the instrument issues a low stack insulation resistance alarm when the stack insulation resistance is less than the first set threshold value to remind the user of the stack status.

[0018] The present invention also provides a purge control method for a commercial vehicle hydrogen fuel cell stack, comprising:

[0019] A first purge pipe is provided so that the output pipeline of the air compressor is connected to the purge port of the fuel cell stack through the first purge pipe, and a one-way valve is provided on the first purge pipe;

[0020] A second purge pipe is provided to connect the brake air source to the purge port of the fuel cell stack through the second purge pipe, and a low-pressure purge valve is provided on the second purge pipe;

[0021] Obtaining a stack insulation resistance value, and when the stack insulation resistance value is less than a first set threshold value, the vehicle controller controls the low-pressure purge valve to be turned on, so that the brake air source purges the interior of the stack through the second purge pipe until the stack insulation resistance value reaches the second set threshold value;

[0022] When the insulation resistance of the fuel cell stack is greater than a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

[0023] Preferably, it also includes:

[0024] When the driver turns the key and puts the ignition switch in the IG position, the vehicle is powered on at low voltage to supply power to the vehicle controller and battery stack inspection device.

[0025] When the ignition switch is in the ON position and the insulation resistance of the battery stack is greater than the second set threshold, the vehicle controller controls the high-voltage power supply of the vehicle to be turned on.

[0026] Preferably, it also includes:

[0027] The operating status of the fuel cell stack is obtained through the fuel cell stack inspection device. After the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started according to the operating status of the fuel cell stack. If so, the air compressor is controlled to start to purge the inside of the fuel cell stack.

[0028] Preferably, it also includes:

[0029] When the stack insulation resistance is less than the first set threshold, the stack status is fed back to the instrument to issue a low stack insulation resistance alarm, and a fault light is turned on to remind the user of the stack status.

[0030] Preferably, it also includes:

[0031] When the stack insulation resistance is greater than the first set threshold, the vehicle controller no longer sends a low stack insulation resistance alarm signal to the instrument to turn off the fault light and control the low-pressure purge valve to close.

[0032] The present invention provides a purge control system and method for a commercial vehicle hydrogen fuel cell stack. By providing a first purge pipe and a second purge pipe, when the stack insulation resistance is less than a first set threshold, a brake air source is controlled to purge the stack through the second purge pipe, thereby increasing the stack insulation resistance. When the stack insulation resistance is greater than the second set threshold, an air compressor is controlled to purge the stack through the first purge pipe, thereby controlling the high-voltage conduction of the entire vehicle. This solves the problem of existing commercial vehicle hydrogen fuel cell stacks being unable to purge the interior of the stack in humid environments, resulting in the vehicle being unable to start, thereby improving user convenience and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments.

[0034] Figure 1This is a schematic diagram of a purge control system for a commercial vehicle hydrogen fuel cell stack provided by the present invention.

[0035] Figure 2 A schematic diagram of a purge control method for a commercial vehicle hydrogen fuel cell stack provided by the present invention. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the solutions of the embodiments of the present invention, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings and implementation methods.

[0037] In response to the problem that the air compressor of the current commercial vehicle hydrogen fuel cell stack is easily unable to purge the inside of the cell stack in a humid environment, and the vehicle cannot be started, the present invention provides a purge control system and method for the commercial vehicle hydrogen fuel cell stack, which solves the problem that the air compressor of the current commercial vehicle hydrogen fuel cell stack is easily unable to purge the inside of the cell stack in a humid environment, and the vehicle cannot be started, and can improve the convenience and safety of users.

[0038] like Figure 1 As shown, a purge control system for a commercial vehicle hydrogen fuel cell stack includes: a vehicle controller (VCU), a stack inspection device (CVM), an air compressor, a brake air source, a low-pressure purge valve, and a one-way valve. The air compressor's output pipeline is connected to the stack's purge port via a first purge pipe, on which the one-way valve is installed. The brake air source is connected to the stack's purge port via a second purge pipe, on which the low-pressure purge valve is installed. The vehicle controller (VCU) is signal-connected to the stack inspection device (CVM), the air compressor, and the low-pressure purge valve. The stack inspection device is used to detect the stack's insulation resistance and provide feedback to the vehicle controller. When the stack's insulation resistance is less than a first set threshold, the vehicle controller controls the low-pressure purge valve to open, allowing the brake air source to purge the interior of the stack through the second purge pipe until the stack's insulation resistance reaches a second set threshold. When the insulation resistance of the fuel cell stack is greater than a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

[0039] Specifically, when the driver turns the key to the IG gear, the vehicle starts the low-voltage electricity. After the low-voltage electricity is turned on, the vehicle controller VCU and the battery stack inspection device CVM are started. The battery stack inspection device CVM begins to detect the insulation resistance of the battery stack, and then feeds back the status to the vehicle controller VCU. If the insulation resistance of the stack is less than the first set threshold, the low-pressure purge valve is controlled to be turned on so that the brake air source can purge the inside of the battery stack through the second purge pipe until the insulation resistance of the battery stack reaches the second set threshold. If the insulation resistance of the battery stack is greater than the second set threshold, the air compressor is controlled to operate so that the air compressor can purge the inside of the battery stack through the first purge pipe. This system ensures that the inside of the battery stack can still be purged when high-voltage power supply is not available. After the insulation resistance of the battery stack reaches the required value, the high voltage can be started, avoiding the after-sales service situation caused by this.

[0040] The system also includes an ignition switch, which is signal-connected to the vehicle controller and the stack inspection device. When the ignition switch is in the IG position, the vehicle low-voltage power supply is activated to power the vehicle controller and the stack inspection device. When the ignition switch is in the ON position and the stack insulation resistance is greater than the second set threshold, the vehicle controller controls the vehicle high-voltage power supply to be turned on.

[0041] In actual application, if the insulation resistance of the battery stack meets the use requirements, when the key is turned to the IG position, the vehicle controller VCU and the battery stack inspection device CVM are started, and the vehicle is started at low voltage.

[0042] The CVM (Cellular Module) monitors the stack insulation resistance and sends it back to the vehicle controller (VCU). The VCU determines if the insulation resistance is greater than or equal to the design requirement. Upon receiving the driver's "ON" signal, the VCU activates the high-voltage power supply, allowing the vehicle to operate normally. While the stack is operating, the air compressor activates and purges the stack through the pipeline, ensuring proper operation.

[0043] Furthermore, after the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started. If so, it controls the air compressor to start to purge the inside of the fuel cell stack.

[0044] The system also includes: instruments; the instruments are connected to the vehicle controller signal, and the instruments issue a low stack insulation resistance alarm when the stack insulation resistance is less than the first set threshold to remind the user of the stack status.

[0045] In actual use, when the driver turns the key to the IG gear, the vehicle starts the low-voltage electricity. After the vehicle is powered on at low voltage, the vehicle controller VCU and the battery stack inspection device CVM start, and the battery stack inspection device CVM begins to detect the insulation resistance of the battery stack, and then feeds back the status to the vehicle controller VCU. The VCU feeds back the battery stack insulation resistance status to the instrument ICM to remind the user of the battery stack status, and at the same time controls the opening and closing of the low-pressure purge valve to achieve the purpose of whether low-pressure purge is needed. The one-way valve prevents gas escape during low-voltage purge and enhances the purge effect.

[0046] It can be seen that the present invention provides a purge control system for a commercial vehicle hydrogen fuel cell stack. By providing a first purge pipe and a second purge pipe, when the insulation resistance of the cell stack is less than a first set threshold, the brake air source is controlled to purge the cell stack through the second purge pipe, thereby increasing the insulation resistance of the cell stack. When the insulation resistance of the cell stack is greater than the second set threshold, the air compressor is controlled to purge the cell stack through the first purge pipe, thereby controlling the high-voltage conduction of the entire vehicle. This solves the problem that the air compressor of existing commercial vehicle hydrogen fuel cell stacks is easily unable to purge the interior of the cell stack in humid environments, thereby preventing the vehicle from starting, and can improve user convenience and safety.

[0047] Accordingly, if Figure 2 As shown, the present invention also provides a purge control method for a commercial vehicle hydrogen fuel cell stack, comprising:

[0048] S1: Setting a first purge pipe so that the output pipeline of the air compressor is connected to the purge port of the fuel cell stack through the first purge pipe, and a one-way valve is provided on the first purge pipe.

[0049] S2: A second purge pipe is provided to connect the brake air source to the purge port of the fuel cell stack through the second purge pipe, and a low-pressure purge valve is provided on the second purge pipe.

[0050] S3: Obtaining the insulation resistance of the battery stack. When the insulation resistance of the battery stack is less than a first set threshold, the vehicle controller controls the low-pressure purge valve to be turned on, so that the brake air source purges the interior of the battery stack through the second purge pipe until the insulation resistance of the battery stack reaches a second set threshold.

[0051] S4: When the insulation resistance of the fuel cell stack increases to a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

[0052] The method further includes:

[0053] When the driver turns the key and puts the ignition switch in the IG position, the vehicle is powered on at low voltage to supply power to the vehicle controller and battery stack inspection device.

[0054] When the ignition switch is in the ON position and the insulation resistance of the battery stack is greater than the second set threshold, the vehicle controller controls the high-voltage power supply of the vehicle to be turned on.

[0055] In actual application, when the insulation resistance of the battery stack does not meet the design requirements: the key is turned to the IG position, the VCU and CVM are started, and the vehicle is started at low voltage. The battery stack inspection device CVM feeds back the insulation resistance of the battery stack to the vehicle controller VCU. When the vehicle controller VCU determines that the insulation resistance is less than the design requirement,

[0056] a) After the vehicle controller VCU receives the driver's ON gear (vehicle start, the same below) signal, the vehicle cannot start the high-voltage power supply and the vehicle cannot be driven.

[0057] b) The vehicle controller VCU sends the stack insulation resistance fault to the instrument, and the fault light reminds the user of the insulation resistance fault.

[0058] c) The vehicle controller VCU controls the low-pressure purge valve to open and uses the high-pressure gas of the vehicle's braking system for purge.

[0059] d) After the stack is purged, the insulation resistance increases, and the latest insulation resistance signal is sent to the stack inspection device CVM.

[0060] e) This cycle stops when the insulation resistance of the battery stack is greater than or equal to the design insulation resistance.

[0061] The method further includes:

[0062] The operating status of the fuel cell stack is obtained through the fuel cell stack inspection device. After the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started according to the operating status of the fuel cell stack. If so, the air compressor is controlled to start to purge the inside of the fuel cell stack.

[0063] The method further includes:

[0064] When the stack insulation resistance is less than the first set threshold, the stack status is fed back to the instrument to issue a low stack insulation resistance alarm, and a fault light is turned on to remind the user of the stack status.

[0065] The method further includes:

[0066] When the stack insulation resistance is greater than the first set threshold, the vehicle controller no longer sends a low stack insulation resistance alarm signal to the instrument to turn off the fault light and control the low-pressure purge valve to close.

[0067] In actual applications, the insulation resistance of the battery stack increases after the braking source blows the battery stack. When the insulation resistance of the battery stack is greater than or equal to the design insulation resistance, at this time:

[0068] a) The VCU no longer sends insulation resistance fault signals to the ICM, and the instrument fault light disappears;

[0069] b) The VCU no longer sends the low-pressure purge valve opening signal, and the low-pressure purge valve closes;

[0070] c) At this time, after the driver turns on the power, the whole vehicle starts high-voltage power supply.

[0071] As can be seen, the present invention provides a purge control method for a commercial vehicle hydrogen fuel cell stack. By providing a first purge pipe and a second purge pipe, when the insulation resistance of the cell stack is less than a first set threshold, the brake air source is controlled to purge the cell stack through the second purge pipe, thereby increasing the insulation resistance of the cell stack. When the insulation resistance of the cell stack is greater than the second set threshold, the air compressor is controlled to purge the cell stack through the first purge pipe, thereby controlling the high-voltage conduction of the entire vehicle. This solves the problem that the air compressor of existing commercial vehicle hydrogen fuel cell stacks is easily unable to purge the interior of the cell stack in humid environments, thereby preventing the vehicle from starting. This can improve user convenience and safety.

[0072] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the scope of implementation of the present invention is not limited to what is shown in the drawings. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which do not exceed the spirit covered by the description and drawings, should be within the scope of protection of the present invention.

Claims

1. A purge control system for a commercial vehicle hydrogen fuel cell stack, characterized in that: include: Vehicle controller, battery stack inspection device, air compressor, brake air source, low-pressure purge valve and one-way valve; The output pipeline of the air compressor is connected to the purge port of the fuel cell stack through a first purge pipe, and the first purge pipe is provided with the one-way valve; The brake air source is connected to the purge port of the fuel cell stack through a second purge pipe, and the second purge pipe is provided with the low-pressure purge valve; The vehicle controller is respectively connected to the stack inspection device, the air compressor and the low-pressure purge valve signal; The stack inspection device is used to detect the insulation resistance of the stack and feed back the insulation resistance status of the stack to the vehicle controller; The vehicle controller controls the low-pressure purge valve to be turned on when the insulation resistance of the fuel cell stack is less than a first set threshold value, so that the brake air source purges the interior of the fuel cell stack through the second purge pipe until the insulation resistance of the fuel cell stack reaches the second set threshold value; When the insulation resistance of the fuel cell stack is greater than a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

2. The purge control system for a commercial vehicle hydrogen fuel cell stack according to claim 1, characterized in that: Also includes: ignition switch; The ignition switch is respectively connected to the vehicle controller and the stack inspection device by signal. When the ignition switch is in the IG position, the vehicle is started at low voltage to supply power to the vehicle controller and the stack inspection device. The vehicle controller controls the high-voltage power supply of the vehicle to be turned on when the ignition switch is in the ON position and the insulation resistance of the battery stack is greater than the second set threshold.

3. The purge control system for a commercial vehicle hydrogen fuel cell stack according to claim 2, characterized in that: After the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started. If so, it controls the air compressor to start to purge the inside of the fuel cell stack.

4. The purge control system for a commercial vehicle hydrogen fuel cell stack according to claim 3, characterized in that: Also includes: Instruments; The instrument is connected to the vehicle controller signal, and the instrument issues a low stack insulation resistance alarm when the stack insulation resistance is less than the first set threshold value to remind the user of the stack status.

5. A purge control method for a commercial vehicle hydrogen fuel cell stack, characterized in that: include: A first purge pipe is provided so that the output pipeline of the air compressor is connected to the purge port of the fuel cell stack through the first purge pipe, and a one-way valve is provided on the first purge pipe; A second purge pipe is provided to connect the brake air source to the purge port of the fuel cell stack through the second purge pipe, and a low-pressure purge valve is provided on the second purge pipe; Obtaining a stack insulation resistance value, and when the stack insulation resistance value is less than a first set threshold value, the vehicle controller controls the low-pressure purge valve to be turned on, so that the brake air source purges the interior of the stack through the second purge pipe until the stack insulation resistance value reaches the second set threshold value; When the insulation resistance of the fuel cell stack is greater than a second set threshold, the vehicle controller controls the operation of the air compressor so that the air compressor purges the interior of the fuel cell stack through the first purge pipe, wherein the second set threshold is greater than the first set threshold.

6. The purge control method for a commercial vehicle hydrogen fuel cell stack according to claim 5, characterized in that: Also includes: When the driver turns the key and puts the ignition switch in the IG position, the vehicle is powered on at low voltage to supply power to the vehicle controller and battery stack inspection device. When the ignition switch is in the ON position and the insulation resistance of the battery stack is greater than the second set threshold, the vehicle controller controls the high-voltage power supply of the vehicle to be turned on.

7. The purge control method for a commercial vehicle hydrogen fuel cell stack according to claim 6, characterized in that: Also includes: The operating status of the fuel cell stack is obtained through the fuel cell stack inspection device. After the high-voltage power supply of the vehicle is turned on, the vehicle controller determines whether the fuel cell stack is started according to the operating status of the fuel cell stack. If so, the air compressor is controlled to start to purge the inside of the fuel cell stack.

8. The purge control method for a commercial vehicle hydrogen fuel cell stack according to claim 7, characterized in that: Also includes: When the stack insulation resistance is less than the first set threshold, the stack status is fed back to the instrument to issue a low stack insulation resistance alarm, and a fault light is turned on to remind the user of the stack status.

9. The purge control method for a commercial vehicle hydrogen fuel cell stack according to claim 8, characterized in that: Also includes: When the stack insulation resistance is greater than the first set threshold, the vehicle controller no longer sends a low stack insulation resistance alarm signal to the instrument to turn off the fault light and control the low-pressure purge valve to close.

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