Shutdown control method for fuel cell system

Abstract

The invention discloses a shutdown control method for a fuel cell system, which comprises the following steps of: firstly, using a limited power fault trigger flag bit as the input of a functional module, forming a basic accumulator by matching with a delay module, a logic gate module, a trigger subsystem module and an addition module, and accumulating and counting the triggering times of the same limited power fault; when the number of times of fault triggering exceeds a threshold value, the system is controlled to perform shutdown operation, and the system is allowed to be restarted only when a fundamental problem which causes frequent triggering of a limited power fault is solved, so that the service life of a galvanic pile can be effectively protected; secondly, in the actual use process, the threshold value of the number of times of fault triggering is set to be a calibration value, the severity degree is judged according to the threshold value, different shutdown processes including normal shutdown, fault shutdown, emergency shutdown and the like of the gas-electricity system are associated, the function module can be better used in different complex application scenes, universality is improved, and the application range of the gas-electricity system is widened. And the gas-electricity system and the electric pile are protected more accurately.

Description

Technical Field

[0001] The present invention belongs to the field of fuel cell systems, and in particular, relates to a shutdown control method for a fuel cell system. Background Art

[0002] Fuel cells are devices that convert the chemical energy of fuel directly into electrical energy. Due to their high efficiency and pollution-free characteristics, they have great development potential and application prospects. There are many types of fuel cells. The most mature and widely used one is the proton exchange membrane fuel cell, which works by converting chemical energy into electrical energy by generating water and electrons through electrochemical reactions between hydrogen and oxygen.

[0003] The fuel cell system mainly includes several modules such as hydrogen subsystem, air subsystem, hydrothermal subsystem, and electrical subsystem. The fuel-electric system requires the cooperation between the subsystems to ensure its normal operation. When the power limit fault of the system is triggered, the system will limit the power output. After the fault is self-healed, the system can be loaded again. If the fundamental problem that triggers the power limit fault is not solved, the system may frequently limit power and frequently increase and decrease load, affecting the life of the fuel cell stack.

[0004] At present, the fault level of power limit faults is generally set low, that is, when a power limit fault occurs, the fuel-fired power system only performs power limit and will not shut down. Moreover, faults of this level can be self-healed, which can meet the needs of the fuel-fired power system to reload power. However, if the same power limit fault frequently triggers self-healing, it will cause the fuel-fired power system to frequently change loads in a short period of time, seriously affecting the service life of the fuel cell stack. Therefore, when the above situation occurs, the system needs to be shut down, and the fuel-fired power system can only be allowed to restart after the developers analyze the data to find the root problem and solve it. Summary of the invention

[0005] In view of the problem that the existing fuel cell system power limiting control strategy usually matches power limiting faults with power limiting triggering conditions one by one, if the same power limiting fault frequently triggers self-healing in a short period of time, the fuel-electric system will frequently change load, causing irreversible damage to the life of the fuel cell stack, the present invention provides a fuel cell system shutdown control method.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0007] A fuel cell system shutdown control method, comprising the steps of:

[0008] S1. Use the power limit fault trigger flag as the input of the functional module, use the delay module and the logic gate module to diagnose the fault trigger state, and use them as the trigger and input signal of the accumulator;

[0009] S2, using the fault trigger state signal processed in step S1 as the trigger and input signal of the accumulator, and using the trigger subsystem module and the addition module to build a basic accumulator;

[0010] S3, using a basic accumulator built in step S2 to obtain a fault triggering number signal, and using a relational operator module and a calibration module to perform a logical judgment on the fault triggering number;

[0011] S4. When the number of fault triggering times is greater than the set calibration threshold, the output flag signal is 1, and the flag signal is associated with the shutdown process.

[0012] Further, in step S1, when the fault trigger flag position is 1 and the fault non-trigger flag position is 0, the Delay module and the AND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle; when the fault trigger flag position is 0 and the fault non-trigger flag position is 1, the Delay module and the NAND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle.

[0013] Further, in step S2, when the fault trigger state signal is 1, the trigger subsystem module starts working; the trigger subsystem uses the fault trigger state signal, the addition module and the Delay module to accumulate the number of fault triggers starting from 1, and outputs the accumulated fault trigger number signal.

[0014] Furthermore, in step S4, the flag signal is associated with the shutdown process, and the severity is determined according to the fault triggering number threshold, so as to control the fuel-electric system to perform different shutdown processes.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The power limit fault trigger flag is used as the input of the functional module, and the delay module, logic gate module, trigger subsystem module and addition module are used to form a basic accumulator to accumulate and count the number of times the same power limit fault is triggered. When the number of fault triggers exceeds the threshold, the control system shuts down. The system is allowed to restart only when the fundamental problem that causes the frequent triggering of the power limit fault is solved, which can effectively protect the service life of the fuel cell stack. Secondly, in actual use, the fault trigger number threshold is set to a calibration value, and the severity is judged according to the threshold value. Different shutdown processes of the fuel-electric system are associated, including normal shutdown, fault shutdown and emergency shutdown, etc., so that the functional module can be better used in different complex application scenarios, improve universality, and more accurately protect the fuel-electric system and fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an overall flow chart of a fuel cell system shutdown control method in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0019] like Figure 1 As shown, this embodiment provides a fuel cell system shutdown control method, comprising the steps of:

[0020] S1. Use the power limit fault trigger flag as the input of the functional module, use the delay module and the logic gate module to diagnose the fault trigger state, and use them as the trigger and input signal of the accumulator;

[0021] S2, using the fault trigger state signal processed in step S1 as the trigger and input signal of the accumulator, and using the trigger subsystem module and the addition module to build a basic accumulator;

[0022] S3, using a basic accumulator built in step S2 to obtain a fault triggering number signal, and using a relational operator module and a calibration module to perform a logical judgment on the fault triggering number;

[0023] S4. When the number of fault triggering times is greater than the set calibration threshold, the output flag signal is 1, and the flag signal is associated with the shutdown process.

[0024] In step S1, when the fault trigger flag is at position 1 and the fault non-trigger flag is at position 0, the Delay module and the AND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle; when the fault trigger flag is at position 0 and the fault non-trigger flag is at position 1, the Delay module and the NAND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle.

[0025] In step S2, when the fault trigger state signal is 1, the trigger subsystem module starts working; the trigger subsystem uses the fault trigger state signal, the addition module and the Delay module to accumulate the number of fault triggers starting from 1, and outputs the accumulated fault trigger number signal.

[0026] In step S4, the flag signal is associated with the shutdown process, and the severity is determined according to the fault triggering number threshold, so as to control the fuel-electric system to perform different shutdown processes.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The power limit fault trigger flag is used as the input of the functional module, and the delay module, logic gate module, trigger subsystem module and addition module are used to form a basic accumulator to accumulate and count the number of times the same power limit fault is triggered. When the number of fault triggers exceeds the threshold, the control system shuts down. The system is allowed to restart only when the fundamental problem that causes the frequent triggering of the power limit fault is solved, which can effectively protect the service life of the fuel cell stack. Secondly, in actual use, the fault trigger number threshold is set to a calibration value, and the severity is judged according to the threshold value. Different shutdown processes of the fuel-electric system are associated, including normal shutdown, fault shutdown and emergency shutdown, etc., so that the functional module can be better used in different complex application scenarios, improve universality, and more accurately protect the fuel-electric system and fuel cell stack.

[0029] The key point and protection point of the present invention is that, according to the actual triggering situation of the fault flag, different logic gate modules are selected, and an accumulator is set in conjunction with the trigger subsystem module, the delay module and the addition module to accumulate the number of fault triggers, and the threshold of the number of fault triggers is set as a calibration quantity, and different shutdown processes of the fuel-electric system are associated according to the severity to better protect the system.

[0030] The above is a detailed introduction to a fuel cell system shutdown control method provided by the present application. The description of the specific embodiment is only used to help understand the method and its core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A fuel cell system shutdown control method, characterized in that: Includes steps: S1. Use the power limit fault trigger flag as the input of the functional module, use the delay module and the logic gate module to diagnose the fault trigger state, and use them as the trigger and input signal of the accumulator; S2, using the fault trigger state signal processed in step S1 as the trigger and input signal of the accumulator, and using the trigger subsystem module and the addition module to build a basic accumulator; S3, using a basic accumulator built in step S2 to obtain a fault triggering number signal, and using a relational operator module and a calibration module to perform a logical judgment on the fault triggering number; S4. When the number of fault triggering times is greater than the set calibration threshold, the output flag signal is 1, and the flag signal is associated with the shutdown process.

2. A fuel cell system shutdown control method according to claim 1, characterized in that: In step S1, when the fault trigger flag is at position 1 and the fault non-trigger flag is at position 0, the Delay module and the AND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle; when the fault trigger flag is at position 0 and the fault non-trigger flag is at position 1, the Delay module and the NAND gate module are used to count the fault trigger status of the previous cycle and the fault trigger status of the current cycle.

3. A fuel cell system shutdown control method according to claim 2, characterized in that: In step S2, when the fault trigger state signal is 1, the trigger subsystem module starts working; the trigger subsystem uses the fault trigger state signal, the addition module and the Delay module to accumulate the number of fault triggers starting from 1, and outputs the accumulated fault trigger number signal.

4. A fuel cell system shutdown control method according to claim 3, characterized in that: In step S4, the flag signal is associated with the shutdown process, and the severity is determined according to the fault triggering number threshold, so as to control the fuel-electric system to perform different shutdown processes.

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