A coupling control method for a fuel cell vehicle

Abstract

The application provides a coupling control method of a fuel cell vehicle, comprising the following steps: 1) performing pure electric operation; 2) judging whether a fuel cell rocker switch is ON during operation, if YES, turning to step 9), if NO, turning to step 3); 3) judging whether t>t0 is satisfied, if YES, turning to step 4), if NO, turning to step 2); 4) sending a fuel cell self-check command; 5) completing self-check of the fuel cell; 6) judging whether the self-check is successful, if YES, turning to step 8), if NO, turning to step 7); 7) updating a fuel cell state flag to 0; 8) updating the fuel cell state flag to 1 and returning to step 1); 9) judging whether the fuel cell state flag is 1, if YES, turning to step 10), if NO, turning to step 11); 10) starting in a fast starting mode; and 11) starting in a normal starting mode. The method meets the reliability, safety and dynamic characteristic requirements of the fuel cell vehicle.

Description

Technical Field

[0001] This invention relates to the field of fuel cell vehicle technology, and in particular to a control method for fuel cell vehicles, specifically a coupling control method for fuel cell vehicles. Background Technology

[0002] Fuel cell vehicles are an important component of new energy vehicles. For example... Figure 1 As shown, a typical fuel cell vehicle's power system includes a power battery 5, a fuel cell 1, a DC / DC converter 2, accessories 6, a DC / AC converter 3, and a motor 4. Both the power battery 5 and the fuel cell 1 provide power. The DC / DC converter transforms the fuel cell output voltage into the fuel cell vehicle's power system bus voltage, and the DC / AC converter transforms the power system's DC bus voltage into the motor's AC voltage.

[0003] However, current fuel cell vehicles typically separate the control of the vehicle, power battery, and fuel cell, resulting in low integration and a risk of insufficient power due to fuel cell failure when the power battery's state of charge (SOC) is low during high-speed operation, posing a significant safety hazard. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a coupling control method for fuel cell vehicles, which assesses the risk of fuel cell failure to start in advance, shortens the fuel cell start-up time, and simultaneously meets the reliability, safety and dynamic characteristics of fuel cell vehicles.

[0005] Therefore, the present invention provides the following technical solution:

[0006] A coupling control method for a fuel cell vehicle, characterized by comprising the following steps:

[0007] 1) Fuel cell vehicles operate in pure electric mode using power batteries;

[0008] 2) During pure electric operation, determine whether the rocker switch of the fuel cell is ON. If yes, proceed to step 9); otherwise, proceed to step 3.

[0009] 3) Determine whether t>t0 is satisfied, where t0 refers to the time required for the fuel cell self-test and t is the current time when the fuel cell self-test is allowed. If yes, proceed to step 4); otherwise, proceed to step 2.

[0010] 4) Send a fuel cell self-test command to the fuel cell system;

[0011] 5) The fuel cell system completes a self-test of the fuel cell;

[0012] 6) Determine whether the fuel cell self-test is successful. If yes, proceed to step 8); otherwise, proceed to step 7.

[0013] 7) Update the fuel cell status flag to 0, indicating that the fuel cell status is abnormal;

[0014] 8) Update the fuel cell status flag to 1, indicating that the fuel cell is in normal condition, and return to step 1);

[0015] 9) Determine if the fuel cell status flag is 1. If yes, proceed to step 10); otherwise, proceed to step 11.

[0016] 10) The fuel cell starts in a fast start mode;

[0017] 11) The fuel cell is started in the normal start-up mode, and the fuel cell status flag is updated according to the self-test results during the start-up process.

[0018] Furthermore, in step 3), t = ΔC / P, where ΔC is the remaining energy capacity of the power battery and P is the average operating power of the fuel cell vehicle under the power battery.

[0019] Furthermore, in step 5), the self-test of the fuel cell includes, but is not limited to, the sealing test of the hydrogen path, the detection of cross-leakage in the fuel cell stack, and the detection of the condition of components.

[0020] Furthermore, in step 5), the self-test of the fuel cell refers to the test under the constraint that the output power of the fuel cell is not greater than 0.

[0021] Furthermore, step 7) also includes: feeding back the abnormal state of the fuel cell to the fuel cell vehicle, and updating the control strategy of the fuel cell vehicle according to the SOC of the power battery.

[0022] Furthermore, the control strategy for fuel cell vehicles is updated based on the SOC status of the power battery. Specifically, when the fuel cell is in an abnormal state, the fuel cell vehicle's only power source is the power battery. It is necessary to determine whether to reduce power or notify the driver based on the SOC status of the power battery.

[0023] Furthermore, the fast start mode in step 10) refers to the start mode in which the fuel cell does not require self-testing.

[0024] Furthermore, the conventional start-up mode in step 11) refers to the start-up mode of the fuel cell that includes a self-test process.

[0025] Compared with the prior art, the beneficial effects of the coupling control method for fuel cell vehicles of the present invention are as follows: A coupling control method for fuel cell vehicles is proposed. In the pure electric operation mode of the fuel cell, it is determined whether the fuel cell self-test function can be activated based on its operating status. Based on the result of the self-test function, the operating status of the fuel cell vehicle and the start-up mode of the fuel cell are adjusted. This method assesses the risk of the fuel cell failing to start in advance, shortens the start-up time of the fuel cell, and simultaneously satisfies the reliability, safety and dynamic characteristics of the fuel cell vehicle. Attached Figure Description

[0026] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same parts.

[0027] Figure 1 A schematic diagram of the power system of a fuel cell vehicle is shown.

[0028] Figure 2 A flowchart of the coupling control method for fuel cell vehicles according to the present invention is shown. Detailed Implementation

[0029] Embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0030] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0031] Figure 2 A flowchart of the coupling control method for a fuel cell vehicle according to the present invention is shown. Figure 2 As shown, the coupling control method for fuel cell vehicles of the present invention includes the following steps:

[0032] S01: Begin.

[0033] As with any method, the first step of the coupling control method for fuel cell vehicles of the present invention is also the beginning.

[0034] S02: Fuel cell vehicles operate in pure electric mode using a power battery.

[0035] After starting, the fuel cell vehicle operates purely on electric power provided by the power battery 5.

[0036] S03: Determine whether the rocker switch of the fuel cell is ON.

[0037] Because the fuel cell can only start when the rocker switch of the fuel cell is ON, if you want to start the fuel cell during pure electric operation of the fuel cell vehicle, you first need to determine whether the rocker switch of the fuel cell is ON. If yes, proceed to step S11; otherwise, proceed to step S04.

[0038] S04: Determine whether t>t0 is satisfied.

[0039] When the rocker switch of the fuel cell is not ON, it is necessary to determine whether the conditions for starting the fuel cell exist. In this invention, the conditions for starting the fuel cell are determined by whether t > t0.

[0040] Where t0 refers to the time required for the fuel cell to self-test, and t is the current time when the fuel cell self-test is deemed permissible. t = ΔC / P, where ΔC is the remaining energy capacity of the power battery, and P is the average operating power of the fuel cell vehicle under power battery conditions.

[0041] If t > t0, it means the conditions for starting the fuel cell are met, and the process proceeds to step S05 for the next step; otherwise, it means the conditions for starting the fuel cell are not met, and the process returns to step S03 without proceeding to the next step.

[0042] S05. Send a fuel cell self-test command to the fuel cell system.

[0043] Once the conditions for starting the fuel cell are met, a fuel cell self-test command is first sent to the fuel cell system so that the fuel cell can be started only after the fuel cell has completed its self-test, thus ensuring safety.

[0044] S06. The fuel cell system completes the self-test of the fuel cell.

[0045] After receiving the self-test command, the fuel cell system begins to perform a self-test on the fuel cell.

[0046] In this invention, the self-testing of the fuel cell includes, but is not limited to, testing the sealing of the hydrogen path, detecting chain leakage in the fuel cell stack, and checking the condition of components. It should be noted that the self-testing here typically refers to testing under the constraint that the fuel cell output power is not greater than 0. The purpose of the self-testing is to prevent the fuel cell system from malfunctioning due to component problems.

[0047] S07. Determine whether the fuel cell self-test was successful.

[0048] After the self-test, it is necessary to determine whether the fuel cell self-test was successful. If the self-test is successful, proceed to step S09; if the self-test is unsuccessful, proceed to step S08.

[0049] S08. Update the fuel cell status flag to 0.

[0050] If the self-test fails, update the fuel cell status flag to 0, indicating an abnormal fuel cell status. Then, proceed to step S10 for further processing.

[0051] S09. Update the fuel cell status flag to 1.

[0052] If the self-test is successful, update the fuel cell status flag to 1, indicating that the fuel cell is in normal condition. Then, return to step S02 and turn the fuel cell rocker switch ON for further processing.

[0053] S10. Feedback the abnormal status of the fuel cell to the fuel cell vehicle, and update the control strategy of the fuel cell vehicle according to the SOC status of the power battery.

[0054] Since the fuel cell self-test failed and the fuel cell could not start, the fuel cell vehicle was powered only by battery 5. Therefore, the control strategy of the fuel cell vehicle needed to be updated based on the state of charge (SOC) of battery 5. For example, when the fuel cell was in an abnormal state, the fuel cell vehicle was powered only by the battery, and it was necessary to determine whether to reduce power or notify the driver based on the SOC of the battery.

[0055] S11. Determine if the fuel cell status flag is 1.

[0056] When the rocker switch of the fuel cell is ON, it is necessary to determine whether the fuel cell status flag is 1, that is, to determine whether the fuel cell has successfully completed its self-test, and to adopt different start-up modes according to whether the fuel cell status flag is 1.

[0057] If the fuel cell status flag is determined to be 1, proceed to step S12; if the fuel cell status flag is determined to be not 1, proceed to step S13.

[0058] S12, The fuel cell is started in a fast start mode.

[0059] The fast start mode refers to a start mode in which the fuel cell does not require self-testing.

[0060] If the fuel cell status flag is 1, it means that the fuel cell has successfully completed its self-test. Therefore, it is not necessary to perform a self-test on the fuel cell again during the startup process. At this time, the fuel cell starts in fast start mode.

[0061] S13. The fuel cell is started in a normal start-up mode, and the fuel cell status flag is updated according to the self-test results during the start-up process.

[0062] The conventional start-up mode refers to the start-up mode of the fuel cell that includes a self-test process.

[0063] If the fuel cell status flag is not 1, it indicates that the fuel cell self-test was unsuccessful or not completed. Therefore, a self-test of the fuel cell is required during startup to ensure safety. In this case, the fuel cell is started in the normal startup mode.

[0064] Simultaneously, the fuel cell status flag is updated based on the self-test results during startup. That is, if the self-test is successful, the fuel cell status flag is updated to 1; if the self-test fails, the fuel cell status flag is updated to 0, and the fuel cell cannot be started.

[0065] The coupling control method for fuel cell vehicles of the present invention determines whether the fuel cell self-test function can be activated based on its operating status in pure electric operation mode. Based on the result of the self-test function, the operating status of the fuel cell vehicle and the start-up mode of the fuel cell are adjusted. This method assesses the risk of the fuel cell failing to start in advance, shortens the start-up time of the fuel cell, and simultaneously meets the reliability, safety, and dynamic characteristics requirements of the fuel cell vehicle.

[0066] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to the prior art of the embodiments, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A coupling control method for a fuel cell vehicle, characterized in that, Includes the following steps: 1) Fuel cell vehicles operate in pure electric mode using power batteries; 2) During pure electric operation, determine whether the rocker switch of the fuel cell is ON. If yes, proceed to step 9); otherwise, proceed to step 3. 3) Determine whether t>t0 is satisfied, where t0 refers to the time required for the fuel cell self-test and t is the current time when the fuel cell self-test is allowed. If yes, proceed to step 4); otherwise, proceed to step 2. 4) Send a fuel cell self-test command to the fuel cell system; 5) The fuel cell system completes a self-test of the fuel cell; 6) Determine whether the fuel cell self-test is successful. If yes, proceed to step 8); otherwise, proceed to step 7. 7) Update the fuel cell status flag to 0, indicating that the fuel cell status is abnormal; 8) Update the fuel cell status flag to 1, indicating that the fuel cell is in normal condition, and return to step 1), while setting the fuel cell rocker switch to ON. 9) Determine if the fuel cell status flag is 1. If yes, proceed to step 10); otherwise, proceed to step 11. 10) The fuel cell starts in a fast start mode; 11) The fuel cell is started in the normal start-up mode, and the fuel cell status flag is updated according to the self-test results during the start-up process. In step 3), t = ΔC / P, where ΔC is the remaining energy capacity of the power battery and P is the average operating power of the fuel cell vehicle under the power battery. Step 7) further includes: feeding back the abnormal state of the fuel cell to the fuel cell vehicle, and updating the control strategy of the fuel cell vehicle according to the SOC of the power battery. The fast start mode in step 10) refers to the start mode in which the fuel cell does not require self-testing. The conventional start-up mode in step 11) refers to the start-up mode of the fuel cell that includes a self-test process.

2. The coupling control method for fuel cell vehicles according to claim 1, characterized in that, In step 5), the self-test of the fuel cell includes, but is not limited to, the sealing test of the hydrogen path, the detection of cross-leakage in the fuel cell stack, and the detection of the condition of components.

3. The coupling control method for fuel cell vehicles according to claim 2, characterized in that, In step 5), the self-test of the fuel cell refers to the test under the constraint that the output power of the fuel cell is not greater than 0.

4. The coupling control method for a fuel cell vehicle according to claim 1, characterized in that, The control strategy for fuel cell vehicles is updated based on the SOC status of the power battery. Specifically, when the fuel cell is in an abnormal state, the fuel cell vehicle's only power source is the power battery. It is necessary to determine whether to reduce power or notify the driver based on the SOC status of the power battery.

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