A fuel cell system and method of using the same

Abstract

The present application relates to the technical field of fuel cell, and discloses a fuel cell system and a use method thereof, which comprises an air filter, a flowmeter, an air compressor, a middle cooler, a humidifier, an electric pile and a DC / DC converter, the air filter, the flowmeter, the air compressor and the middle cooler are sequentially connected, the middle cooler is connected with the humidifier, the humidifier is connected with the electric pile, the electric pile is connected with the DC / DC converter, and the system further comprises a three-way valve, a stop valve, two air pressure sensors and an FCU, the three-way valve is arranged on a pipeline between the middle cooler and the humidifier, the stop valve is connected with the humidifier, the two air pressure sensors are arranged at air inlet and outlet of the electric pile respectively, and the air compressor, the three-way valve, the stop valve, the two air pressure sensors and the DC / DC converter are connected with the FCU through a control wire harness.The present application can ensure the supply of oxidant when the current is extracted and ensure the normal start of the system through the air inlet and outlet pile pressure judgment; and the present application can effectively judge the cathode sealing failure state and trigger active maintenance through the shutdown time interval and the potential establishment condition when starting.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fuel cell technology, in particular to a fuel cell system and a method for using the same. BACKGROUND

[0002] With the increasing pressure of environmental protection, hydrogen fuel cell technology with zero emission and high efficiency and no pollution has become a hot spot of current research and commercialization, and the market demand for the service life of fuel cells is also increasingly strict.

[0003] Using cathode sealing to control the frequency of hydrogen-air interface and using start-up potential control technology to control the corrosion of the catalytic layer caused by high potential are important technical solutions for improving the service life of the fuel cell system. Generally, the realization of cathode sealing is achieved by selecting the sealing material of the inlet and outlet valve. During start-up, the control of voltage during the start-up process is realized by controlling the air flow into the stack and the extraction value of the current. However, any sealing is relative, and if the storage time exceeds the design time, the anode and cathode chambers will eventually be filled with air. Furthermore, if the air sealing valve fails, the anode and cathode chambers will be filled with air in a short time. When the initial state of the cathode chamber is air during the start-up process, a voltage will be generated at the moment of hydrogen gas being introduced. According to the general design potential clamping strategy, the voltage will follow the extraction current. At this time, there may be a delay in the supply of oxidizing agent, resulting in a low single voltage or causing an air reverse electrode, which leads to start-up failure. SUMMARY

[0004] In order to solve the problem of start-up failure caused by sealing failure of the prior art fuel cell, the present application provides a fuel cell system and a method for using the same.

[0005] A fuel cell system, comprising an air filter, a flow meter, an air compressor, a intercooler, a humidifier, a stack and a DC / DC converter, the air filter, the flow meter, the air compressor and the intercooler are connected in sequence, the intercooler is connected with the humidifier, the humidifier is connected with the stack, the stack is connected with the DC / DC converter, further comprising a three-way valve, a stop valve, two air pressure sensors and an FCU, the three-way valve is arranged on the pipeline between the intercooler and the humidifier, the stop valve is connected with the humidifier, the two air pressure sensors are arranged at the air inlet and outlet of the stack respectively, and the air compressor, the three-way valve, the stop valve, the two air pressure sensors and the DC / DC converter are connected with the FCU through a control wire harness.

[0006] Further, the three-way valve is arranged on the air inlet pipeline of the humidifier, and the two ends of the three-way valve are connected with the intercooler and the humidifier respectively.

[0007] Further, the stop valve is arranged on the air outlet pipeline of the humidifier.

[0008] Further, the two air pressure sensors are respectively an air pressure sensor for entering the stack and an air pressure sensor for leaving the stack.

[0009] Further, the air pressure sensor for entering the stack is arranged on the air inlet pipeline of the stack, and the air pressure sensor for entering the stack is connected with the humidifier and the air inlet of the stack on both sides; the air pressure sensor for leaving the stack is arranged on the air outlet pipeline of the stack, and the air pressure sensor for leaving the stack is connected with the humidifier and the air outlet of the stack on both sides.

[0010] Further, the FCU is connected with a data acquisition controller, the data acquisition controller is used for collecting data and analyzing, and abnormal data is warned.

[0011] Further, the data acquisition controller is connected with a cloud platform, and the cloud platform is used for providing computing, network and storage capabilities.

[0012] A method for using a fuel cell system, comprising the fuel cell system described above, by the following steps:

[0013] S1: initializing the fuel cell system, checking the communication and the in-situ value of each monitoring sensor after the fuel cell system is powered on, if normal, executing S2, if abnormal, not allowed to start;

[0014] S2: starting the fuel cell system, introducing air, and replacing the hydrogen cavity of the stack;

[0015] S3: if the stack voltage is not more than 0 before the air enters the stack, executing S4; otherwise, if the stack voltage is more than 0, executing S5;

[0016] S4: introducing air into the stack, adjusting the stack voltage value, until the stack voltage value is not greater than the preset high voltage value, completing the voltage establishment, the fuel cell system reaching the run state, responding to the power demand of the VCU, and achieving the purpose of starting the fuel cell system;

[0017] S5: calling the last shutdown time, calculating the shutdown interval time, and judging whether the shutdown interval time is lower than the designed shutdown interval time, if yes, indicating that there is a problem of tight sealing in the cathode, executing S6;

[0018] S6: the fuel cell system reports to the cloud platform through the FCU and the data acquisition controller, informs the maintenance, after the maintenance is completed, re-executing S1.

[0019] Further, the S4 adjusts the stack voltage value by the following steps:

[0020] S41: adjusting the air path executive component, opening the three-way valve and the stop valve, controlling the air compressor to start rotating to reach the preset rotating speed, and gradually adjusting the opening degree of the three-way valve and the stop valve to make the air enter the stack;

[0021] S42: judging whether the air pressure of the stack is greater than a preset value through the out-stack air pressure sensor, if yes, executing S43; otherwise, adjusting the opening degrees of the three-way valve and the stop valve so that the air continues to enter the stack;

[0022] S43: judging whether the voltage of the stack exceeds a preset high voltage value, if yes, executing S44; otherwise, completing the voltage establishment of the stack, the fuel cell system reaching the run state, responding to the power demand of the VCU, and achieving the purpose of starting the fuel cell system;

[0023] S44: adjusting the extraction current Io value until the voltage of the stack does not exceed the preset high voltage value, entering S43, and achieving the purpose of starting the fuel cell system.

[0024] Further, the S5 further comprises replacing S6 with S7: interacting with the vehicle VCU through the FCU, and prompting the maintenance of the air path seal of the fuel cell through the vehicle instrument panel.

[0025] The beneficial effects of the present application at least include: judging the air in-out stack pressure to ensure the supply of oxidant during the extraction current, avoiding abnormal phenomena such as oxygen deficiency and reverse polarity, ensuring the normal starting of the system, and improving the reliability of the system; combining the shutdown time interval with the potential establishment condition during starting to effectively judge the cathode seal failure state, triggering active maintenance, and effectively prolonging the durability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0026] Fig. 1 It is a schematic diagram of the cathode structure of the fuel cell system of the present application.

[0027] Fig. 2 It is a use flowchart of the fuel cell system of the present application.

[0028] Among them:

[0029] 1-air filter;

[0030] 2-flow meter;

[0031] 3-air compressor;

[0032] 4-intercooler;

[0033] 5-three-way valve;

[0034] 6-humidifier;

[0035] 7-in-stack air pressure sensor;

[0036] 8-stack;

[0037] 9-DC / DC converter;

[0038] 10-out-stack air pressure sensor;

[0039] 11 - stop valve;

[0040] 12 - FCU;

[0041] 13 - data acquisition controller;

[0042] 14 - cloud platform. DETAILED DESCRIPTION

[0043] To make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0044] In combination with Figs. 1-2 As shown in the figure, the present application discloses a kind of fuel cell systems, including air filter 1, flowmeter 2, air compressor 3, intercooler 4, humidifier 6, electric pile 8 and DC / DC converter, the air filter 1, flowmeter 2, air compressor 3 and intercooler 4 are sequentially connected, the intercooler 4 is connected with humidifier 6, the humidifier 6 is connected with electric pile 8, the electric pile 8 is connected with DC / DC converter 9, it further includes three-way valve 5, stop valve 11, two air pressure sensors and FCU 12, the three-way valve 5 is arranged on the pipeline between the intercooler 4 and the humidifier 6, the stop valve 11 is connected with the humidifier 6, two the air pressure sensors are respectively arranged at the air inlet and outlet of electric pile 8, the air compressor 3, three-way valve 5, stop valve 11, two air pressure sensors and DC / DC converter 9 are all connected with FCU 12 by control wire harness.

[0045] Further, the three-way valve 5 is arranged on the air inlet pipeline of the humidifier 6, and the three-way valve 5 is connected with the intercooler 4 and the humidifier 6 at two ends respectively.

[0046] Further, the stop valve 11 is arranged on the air outlet pipeline of the humidifier 6.

[0047] Further, the two air pressure sensors are respectively an inlet pile air pressure sensor 7 and an outlet pile air pressure sensor 10.

[0048] Further, the inlet pile air pressure sensor 7 is arranged on the air inlet pipeline of the electric pile 8, and the inlet pile air pressure sensor 7 is connected with the humidifier 6 and the air inlet of the electric pile 8 at two sides respectively, the outlet pile air pressure sensor 10 is arranged on the air outlet pipeline of the electric pile 8, and the outlet pile air pressure sensor 10 is connected with the humidifier 6 and the air outlet of the electric pile 8 at two sides respectively. Further, the three-way valve 5 is arranged on the air inlet pipeline of the humidifier 6, and the three-way valve 5 is connected with the intercooler 4 and the humidifier 6 at two ends respectively.

[0049] Further, the FCU 12 is connected with a data acquisition controller 13, which is used for data acquisition and analysis, and abnormal data warning.

[0050] Further, the data acquisition controller 13 is connected with a cloud platform 14, which is used for providing computing, network and storage capabilities.

[0051] A method for using a fuel cell system, comprising the fuel cell system described above, by the following steps:

[0052] S1: power on, initialize the fuel cell system, and after the fuel cell system is powered on, check the communication and the in-situ value of each monitoring sensor, if normal, execute S2, if abnormal, do not allow power on;

[0053] S2: start the fuel cell system, and input air to replace the hydrogen cavity of the stack;

[0054] S3: if the stack voltage is detected to be not more than 0 before the air is input into the stack, execute S4; otherwise, if the stack voltage is more than 0, execute S5; the stack voltage is detected by a voltage sensor corresponding to a DC / DC converter or a CVM;

[0055] S4: input air into the stack, adjust the stack voltage value, until the stack voltage value is not greater than a preset high voltage value, complete voltage establishment, the fuel cell system reaches a run state, responds to the power demand of the VCU, and reaches the purpose of starting the fuel cell system, and then shut down;

[0056] S5: retrieve the last shutdown time, calculate the shutdown interval time, and determine whether the shutdown interval time is lower than the designed shutdown interval time, if yes, it means that the cathode exists a problem of tight sealing, execute S6;

[0057] S6: the fuel cell system reports to the cloud platform through the FCU and the data acquisition controller, informs the maintenance, after the maintenance is completed, execute S1 again.

[0058] If the stack voltage has exceeded 0 before the air is supplied into the stack, it means that there is oxygen in the corresponding cathode cavity when starting; retrieve the last shutdown time, calculate the shutdown interval time Δt; if the interval time is lower than the designed value Δt0, it means that the cathode exists a problem of tight sealing, at this time, the FCU can report the alarm to the cloud platform through the data acquisition, and inform the maintenance; or the FCU can interact with the VCU of the whole vehicle, and prompt the vehicle instrument panel to repair the air path sealing of the fuel cell.

[0059] Further, the S4 adjusts the stack voltage value by the following steps:

[0060] S41: Adjust the air path execution member, open the three-way valve and the stop valve, control the air compressor to start and reach the preset rotating speed, gradually adjust the three-way valve and the stop valve opening degree to make the air enter the stack; the execution member mainly refers to the air compressor, air inlet and outlet valve and the like;

[0061] S42: Determine whether the stack air pressure is greater than the preset value through the stack air pressure sensor, if yes, execute S43; otherwise, adjust the three-way valve and the stop valve opening degree to make the air continue to enter the stack; determine whether the stack air pressure P_Airout is greater than the preset value P_set, if no, it means that the stack air flow is insufficient, and the state of being able to pull the load has not been reached, so the corresponding valve opening degree needs to be adjusted until the stack air flow meets the demand;

[0062] S43: Determine whether the stack voltage V_stack exceeds the preset high voltage value V_set, if yes, execute S44; otherwise, complete the stack voltage establishment, the fuel cell system reaches the run state, responds to the VCU power demand, and achieves the purpose of starting the fuel cell system;

[0063] S44: Adjust the extraction current Io value until the stack voltage does not exceed the preset high voltage value, enter S43, and achieve the purpose of starting the fuel cell system.

[0064] Further, the S5 further includes replacing S6 with S7: interact with the vehicle VCU through the FCU, and prompt the maintenance of the fuel cell air path through the vehicle instrument panel.

[0065] Through the air in and out of the stack pressure judgment, the oxidant supply when extracting the current is ensured, the oxygen deficiency reverse pole and other abnormal phenomena are avoided, the system normal starting is ensured, and the system reliability is improved; through the shutdown time interval combined with the potential establishment condition when starting, the cathode sealing failure state is effectively judged, the active maintenance is triggered, and the system durability is effectively prolonged.

[0066] The above only describes the embodiments of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent flow conversion obtained by using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection range of the present application.

Claims

1. A fuel cell system comprising an air filter, a flow meter, an air compressor, an intercooler, a humidifier, a stack and a DC / DC converter, the air filter, the flow meter, the air compressor and the intercooler being connected in sequence, the intercooler being connected to the humidifier, the humidifier being connected to the stack, the stack being connected to the DC / DC converter, characterized in that: Also include three-way valve, stop valve, two air pressure sensors and FCU, the three-way valve is arranged on the pipeline between the intercooler and the humidifier, the stop valve is connected with the humidifier, two air pressure sensors are arranged at the air inlet and outlet of the stack respectively, the air compressor, three-way valve, stop valve, two air pressure sensors and DC / DC converter are connected with FCU through control wire harness; Among them, two air pressure sensors are respectively into the stack air pressure sensor and out of the stack air pressure sensor; The into the stack air pressure sensor is arranged on the stack air inlet pipeline, and the into the stack air pressure sensor is connected with the humidifier and the stack air inlet on both sides, the out of the stack air pressure sensor is arranged on the stack air outlet pipeline, and the out of the stack air pressure sensor is connected with the humidifier and the stack air outlet on both sides; The FCU is connected with a data acquisition controller, the data acquisition controller is used for collecting data and analyzing, and the abnormal data is prewarned; The data acquisition controller is connected with a cloud platform, and the cloud platform is used for providing calculation, network and storage capacity.

2. A fuel cell system according to claim 1, characterised in that: The three-way valve is arranged on the humidifier air inlet pipeline, and the three-way valve is connected with the intercooler and the humidifier on both ends.

3. A fuel cell system according to claim 1, wherein: The stop valve is arranged on the humidifier air outlet pipeline.

4. A method of using a fuel cell system comprising the fuel cell system of any of claims 1-3, wherein: Through the following steps: S1: initialize the fuel cell system, make the fuel cell system power on and check the communication and the in-situ value of each monitoring sensor, if normal, execute S2, if abnormal, do not allow to start; S2: start the fuel cell system, pass in air, and replace the hydrogen cavity of the stack; S3: if the stack voltage is not more than 0 before air enters the stack, execute S4, otherwise, if the stack voltage is more than 0, execute S5; S4: make air into the stack, adjust the stack voltage value, until the stack voltage value is not greater than the preset high voltage value, complete voltage establishment, the fuel cell system reaches run state, responds to VCU power demand, and achieves the purpose of starting the fuel cell system; S5: call the last shutdown time, calculate the shutdown interval time, and judge whether the shutdown interval time is lower than the designed shutdown interval time, if yes, it indicates that the cathode exists the problem of tight sealing, execute S6; S6: the fuel cell system reports to the cloud platform through FCU and data acquisition controller, informs maintenance, after maintenance, execute S1 again; Among them, S4 adjusts the stack voltage value through the following steps: S41: adjust the air path executive part, open the three-way valve and the stop valve, control the air compressor to start and reach the preset speed, gradually adjust the opening degree of the three-way valve and the stop valve to make air enter the stack; S42: judge whether the stack air pressure is greater than the preset value through the out of the stack air pressure sensor, if yes, execute S43; Otherwise, adjust the opening degree of the three-way valve and the stop valve to make air continue to enter the stack; S43: judge whether the stack voltage is more than the preset high voltage value, if yes, execute S44; Otherwise, complete the stack voltage establishment, the fuel cell system reaches run state, responds to VCU power demand, and achieves the purpose of starting the fuel cell system; S44: adjust the extraction current Io value until the stack voltage does not exceed the preset high voltage value, enter S43, and achieve the purpose of starting the fuel cell system; Wherein the S5 further comprises replacing the S6 with S7: interacting with the vehicle VCU through the FCU, and prompting the maintenance of the fuel cell air road seal through the vehicle instrument panel.

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