Insulation fault diagnosis system and method of fuel cell system, and fuel cell system

Abstract

The invention relates to an insulation fault diagnosis system and method of a fuel cell system and the fuel cell system. Comprising a troubleshooting assembly with a plurality of troubleshooting nodes, and the troubleshooting assembly is used for adjusting the connection state between the multiple troubleshooting nodes and multiple to-be-troubleshot points according to the current troubleshooting requirement; the control assembly is respectively connected with the plurality of troubleshooting nodes and is used for sending a current troubleshooting demand to the troubleshooting assembly and determining parts in an insulation failure state in the fuel cell system according to a troubleshooting result of each to-be-troubleshot point after the troubleshooting assembly adjusts a connection state between the plurality of troubleshooting nodes and the plurality of to-be-troubleshot points; and the display assembly is connected with the control assembly and is used for displaying the parts in the insulation failure state. Therefore, by means of the insulation fault diagnosis system, the problems that in the prior art, when insulation fault diagnosis is carried out, specific fault parts cannot be automatically positioned, and insulation faults caused by high-voltage loop failure or cooling loop failure cannot be distinguished can be solved.

Description

Technical Field

[0001] This application relates to the technical field of fuel cells, and particularly to an insulation fault diagnosis system and method for a fuel cell system, and a fuel cell system. Background Art

[0002] A fuel cell is an energy conversion device that directly converts the chemical energy in a fuel oxidant into electrical energy through an electrochemical reaction. Taking a hydrogen-oxygen fuel cell as an example, its product is water, and it is hailed as the ultimate energy source for new energy vehicles due to its high energy utilization rate and pollution-free characteristics. Currently, new energy battery vehicles mainly adopt an electric-electric hybrid mode, that is, a mode combining a fuel cell and a power battery for driving. The voltage platform of the power battery is generally 500V (high-voltage platform), so the insulation requirement is relatively high. Among them, the insulation resistance value of the fuel cell system is mainly affected by the conductivity of the fuel cell cooling circuit, the pipeline layout of the cooling circuit, the insulation state of the components in the cooling circuit, and the insulation state of the high-voltage components. Currently, fuel cell insulation faults are generally caused by high conductivity. To avoid the hazards caused by low insulation, real-time insulation detection is performed when the vehicle starts.

[0003] In related technologies, (1) the insulation value of the fuel cell system can be monitored through an insulation detector, and the conductivity of the cooling circuit of the fuel cell system can be monitored through a conductivity meter. Based on these two pieces of data, it can be determined whether there are insulation faults in the internal components of the fuel cell system; (2) an insulation model can be built to theoretically calculate the insulation value, and the fault threshold determination of insulation failure can be made by grounding the outer shell of the components.

[0004] However, when method (1) is used for insulation fault diagnosis, it is impossible to automatically locate the specific faulty component, and further manual testing is required to locate the component with insulation failure; when method (2) is used for insulation fault location, it is prone to misjudgment and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, which needs to be solved urgently. Summary of the Invention

[0005] This application provides an insulation fault diagnosis system and method for a fuel cell system, and a fuel cell system, so as to solve the problems that in the prior art, it is impossible to automatically locate the specific faulty component during insulation fault diagnosis, and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0006] To achieve the above object, the first aspect embodiment of this application proposes an insulation fault diagnosis system for a fuel cell system, including: a fault troubleshooting component, a control component, and a display component, where,

[0007] The fault troubleshooting component includes a plurality of troubleshooting nodes, and the plurality of troubleshooting nodes are respectively connected to a plurality of points to be troubleshot in the fuel cell system one by one, and are used to adjust the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot according to the current troubleshooting requirement;

[0008] The control component is respectively connected to the plurality of troubleshooting nodes, and is used to send the current troubleshooting requirement to the fault troubleshooting component, and after the fault troubleshooting component adjusts the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot based on the current troubleshooting requirement, determine the components in the fuel cell system that are in the insulation failure state according to the troubleshooting results of each point to be troubleshot;

[0009] The display component is connected to the control component, and is used to display the components in the fuel cell system that are in the insulation failure state.

[0010] According to an embodiment of the present application, the fault troubleshooting component includes:

[0011] A switch matrix, one end of the switch matrix is connected to the control component, the other end of the switch matrix is connected to a plurality of points to be troubleshot in the fuel cell system through the plurality of troubleshooting nodes one by one, the switch matrix has multiple switch states, the multiple switch states correspond to multiple troubleshooting requirements, and the switch matrix adjusts the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot according to the current troubleshooting requirement;

[0012] A failure detection unit, one end of the failure detection unit is connected to one end of the switch matrix, the other end of the failure detection unit is connected to a ground node, and the failure detection unit is used to detect the components in the fuel cell system that are in the functional failure state;

[0013] An insulation detection unit, one end of the insulation detection unit is respectively connected to one end of the switch matrix and one end of the failure detection unit, the other end of the insulation detection unit is connected to the ground node, and the insulation detection unit is used to detect the components in the fuel cell system that are in the insulation failure state.

[0014] According to an embodiment of the present application, the switch matrix includes: the first to the Nth switches, where

[0015] One ends of the first to the Nth switches are all connected to one end of the failure detection unit and one end of the insulation detection unit, the other ends of the first to the Nth switches are connected to a plurality of points to be troubleshot in the fuel cell system through the plurality of troubleshooting nodes one by one, and the control ends of the first to the Nth switches are respectively connected to the control component.

[0016] According to an embodiment of the present application, the failure detection unit includes:

[0017] A first resistor, one end of the first resistor is connected to the grounding node;

[0018] An (N + 1)-th switch, one end of the (N + 1)-th switch is connected to the other end of the first resistor, the other end of the (N + 1)-th switch is connected to one ends of the first to N-th switches, and the control end of the (N + 1)-th switch is connected to the control component.

[0019] According to an embodiment of the present application, the insulation detection unit includes:

[0020] A second resistor, one end of the second resistor is connected to the grounding node;

[0021] An (N + 2)-th switch, one end of the (N + 2)-th switch is connected to the other end of the second resistor, the other end of the (N + 2)-th switch is connected to one ends of the first to N-th switches, and the control end of the (N + 2)-th switch is connected to the control component.

[0022] According to an embodiment of the present application, the control component includes:

[0023] The first to (M + 2)-th control units, the first to (M + 2)-th control units are respectively connected to one ends of the first to (N + 2)-th switches in one-to-one correspondence.

[0024] According to an embodiment of the present application, the first to (N + 2)-th switches are MOS transistors.

[0025] In the insulation fault diagnosis system of the fuel cell system proposed according to the embodiment of the present application, the fault detection component adjusts the connection state between multiple detection nodes and multiple points to be detected according to the current detection requirement; the control component sends the current detection requirement to the fault detection component, and after the fault detection component adjusts the connection state between multiple detection nodes and multiple points to be detected, determines the components in the fuel cell system in an insulation failure state according to the detection result of each point to be detected; the display component displays the components in an insulation failure state. Thus, through this insulation fault diagnosis system, it can solve the problems in the prior art that when conducting insulation fault diagnosis, it is impossible to automatically locate the specific faulty components, and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0026] To achieve the above object, an embodiment of the second aspect of the present application proposes a fuel cell system, which includes the insulation fault diagnosis system of the fuel cell system as described in the embodiment of the first aspect.

[0027] To achieve the above object, an embodiment of the third aspect of the present application provides a vehicle, which includes a fuel cell system as described in the embodiment of the third aspect.

[0028] To achieve the above object, an embodiment of the fourth aspect of the present application provides a method for diagnosing an insulation fault of a fuel cell system, which uses the insulation fault diagnosis system of the fuel cell system as described in the embodiment of the first aspect. The method includes the following steps:

[0029] Obtain physical parameters of at least one component of the fuel cell system, calculate theoretical insulation values of the fuel cell system at different conductivities based on a preset conductivity formula and the physical parameters, and determine a preset fault insulation value based on the theoretical insulation values at different conductivities;

[0030] Detect the current insulation value of the fuel cell system. When the current insulation value is less than or equal to the preset fault insulation value, perform a fault check on each component in the cooling circuit through the fault troubleshooting component to determine whether the cooling circuit has an insulation failure;

[0031] If the cooling circuit has an insulation failure, determine the component in the insulation failure state corresponding to the insulation failure of the cooling circuit. Otherwise, perform a fault check on each component in the high-voltage circuit through the fault troubleshooting component to determine whether the high-voltage circuit has an insulation failure and determine the component in the insulation failure state corresponding to the insulation failure of the high-voltage circuit.

[0032] According to the method for diagnosing an insulation fault of a fuel cell system provided by the embodiment of the present application, it is possible to solve the problems in the prior art that it is impossible to automatically locate the specific faulty component during insulation fault diagnosis and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0033] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0035] Figure 1 FIG. is a schematic block diagram of an insulation fault diagnosis system of a fuel cell system according to an embodiment of the present application;

[0036] Figure 2 FIG. is a schematic diagram of a fuel cell system architecture according to an embodiment of the present application;

[0037] Figure 3 Schematic diagram of an equivalent circuit of a fuel cell system architecture according to an embodiment of the present application;

[0038] Figure 4 Schematic diagram of the structure of a fault troubleshooting component according to an embodiment of the present application;

[0039] Figure 5 Schematic diagram of an electrical framework of a fuel cell system according to an embodiment of the present application;

[0040] Figure 6 Flowchart of an insulation fault diagnosis method for a fuel cell system provided according to an embodiment of the present application;

[0041] Figure 7 Flowchart of another insulation fault diagnosis method for a fuel cell system provided according to an embodiment of the present application. Detailed implementation manners

[0042] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as a limitation to the present application.

[0043] The insulation fault diagnosis system and method of a fuel cell system and the fuel cell system proposed according to the embodiments of the present application will be described below with reference to the accompanying drawings.

[0044] Figure 1 Block diagram of an insulation fault diagnosis system of a fuel cell system according to an embodiment of the present application.

[0045] Before introducing the insulation fault diagnosis system of the fuel cell system proposed in the embodiments of the present application, the exemplary system architecture of the embodiments of the present application will be introduced first.

[0046] For example, as Figure 2As shown in the figure, the fuel cell system architecture of the embodiments of the present application may include: insulation 101 from the positive and negative electrodes of the stack module to the grounding point, pipeline 112 from the stack to the thermostat, insulation 103 from the positive and negative electrodes of the thermostat to the water inlet, pipeline 122 from the thermostat to the PTC (Positive Temperature Coefficient Thermistor), insulation 106 from the positive and negative electrodes of the PTC to the grounding point, pipeline 113 from the thermostat to the shunt port 1, pipeline 115 from the shunt port 1 to the intercooler, pipeline 114 from the shunt port 1 to the radiator, high-voltage insulation 109 of the radiator to the ground, pipeline 116 from the intercooler to the confluence port 2, pipeline 117 from the radiator to the confluence port 2, pipeline 119 from the confluence port 2 to the confluence port 3, pipeline 118 from the PTC to the confluence port 3, pipeline 120 from the confluence port 3 to the water pump, insulation 111 from the positive and negative electrodes of the water pump to the grounding point, pipeline 121 from the water pump to the stack, pipeline interface pipeline to-be-investigated point 102 of the stack, thermostat interface pipeline to-be-investigated point 104, PTC interface pipeline to-be-investigated point 105, radiator interface pipeline to-be-investigated point 108, and water pump interface pipeline to-be-investigated point 110.

[0047] According to Figure 2 the actual connection forms of different components and the grounding point positions, etc., an equivalent circuit diagram is drawn. The equivalent circuit diagram is as Figure 3 shown, and it includes: insulation resistance R101 from the positive and negative electrodes of the stack module to the grounding point, equivalent resistance R112 of the pipeline from the stack to the thermostat, insulation resistance R103 from the positive and negative electrodes of the thermostat to the water inlet, equivalent resistance R122 of the pipeline from the thermostat to the PTC, insulation resistance R106 from the positive and negative electrodes of the PTC to the grounding point, equivalent resistance R113 of the pipeline from the thermostat to the shunt port 1, equivalent resistance R115 of the pipeline from the shunt port 1 to the intercooler, equivalent resistance R114 of the pipeline from the shunt port 1 to the radiator, high-voltage insulation resistance R109 of the radiator to the ground, equivalent resistance R116 of the pipeline from the intercooler to the confluence port 2, equivalent resistance R117 of the pipeline from the radiator to the confluence port 2, equivalent resistance R119 of the pipeline from the confluence port 2 to the confluence port 3, equivalent resistance R118 of the pipeline from the PTC to the confluence port 3, equivalent resistance R120 of the pipeline from the confluence port 3 to the water pump, insulation resistance R111 from the positive and negative electrodes of the water pump to the grounding point, equivalent resistance R121 of the pipeline from the water pump to the stack, resistance R102 of the pipeline interface pipeline to-be-investigated point of the stack, resistance R104 of the thermostat interface pipeline to-be-investigated point, resistance R105 of the PTC interface pipeline to-be-investigated point, resistance R108 of the radiator interface pipeline to-be-investigated point, and resistance R110 of the water pump interface pipeline to-be-investigated point.

[0048] Exemplarily, as Figure 1As shown in the figure, the insulation fault diagnosis system 10 of the fuel cell system includes: a fault troubleshooting component 100, a control component 200, and a display component 300. Among them, the fault troubleshooting component 100 includes a plurality of troubleshooting nodes, and the plurality of troubleshooting nodes are respectively connected to a plurality of points to be troubleshot in the fuel cell system one by one, and are used to adjust the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot according to the current troubleshooting requirements; the control component 200 is respectively connected to the plurality of troubleshooting nodes, and is used to send the current troubleshooting requirements to the fault troubleshooting component 100, and after the fault troubleshooting component 100 adjusts the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot based on the current troubleshooting requirements, determine the components in the fuel cell system that are in the insulation failure state according to the troubleshooting results of each point to be troubleshot; the display component 300 is connected to the control component 200, and is used to display the components in the fuel cell system that are in the insulation failure state.

[0049] Specifically, in the embodiment of the present application, the insulation fault conditions of all components in the fuel cell system can be troubleshot one by one through the fault troubleshooting component 100. That is, when there is an insulation failure fault in the fuel cell system, the troubleshooting component 100 can adjust the connection state (such as closing, disconnecting) between the plurality of troubleshooting nodes and the plurality of points to be troubleshot according to the current troubleshooting requirements, so as to troubleshoot the insulation fault conditions of each component in the cooling circuit, thereby confirming whether the cooling circuit is in insulation failure, and locking the components in the cooling circuit that are in the insulation failure state when the cooling circuit is in insulation failure. If the cooling circuit is normal, the troubleshooting component 100 can further adjust the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot according to the current troubleshooting requirements, and troubleshoot the insulation fault conditions of each component in the high-voltage circuit, so as to confirm whether the high-voltage circuit is in insulation failure, and lock the components in the high-voltage circuit that are in the insulation failure state when the high-voltage circuit is in insulation failure; the control component 200 is a controller, which is connected to the plurality of troubleshooting nodes in the fault troubleshooting component 100, and can generate and send the current troubleshooting requirements to the fault troubleshooting component 100 according to a preset troubleshooting strategy (such as troubleshooting one by one). These requirements can include the components to be troubleshot, the backward order of troubleshooting, etc. After the fault troubleshooting component 100 adjusts the connection state of the troubleshooting nodes and the points to be troubleshot based on the current troubleshooting requirements, the control component 200 can collect the troubleshooting results of each component, and through the analysis and processing of these results, the control component 200 can determine which components in the fuel cell system are in the insulation failure state; the display component 300 can display the names, positions, etc. of these components on the interface based on the determined information of the components in the insulation failure state, so that the operator can intuitively understand which parts of the fuel cell system have problems, and thus take corresponding maintenance or replacement measures in time.

[0050] For the convenience of understanding, the fault troubleshooting component 100 will be elaborated in detail below.

[0051] Optionally, in some embodiments, the troubleshooting component 100 includes: a switch matrix 1001, a failure detection unit 1002, and an insulation monitoring unit 1003. One end of the switch matrix 1001 is connected to the control component 200, and the other end of the switch matrix 1001 is connected to multiple points to be troubleshot in the fuel cell system through multiple troubleshooting nodes in one-to-one correspondence. The switch matrix 1001 has multiple switch states, and the multiple switch states correspond to multiple troubleshooting requirements. The switch matrix 1001 adjusts the connection state between the multiple troubleshooting nodes and the multiple points to be troubleshot according to the current troubleshooting requirement; One end of the failure detection unit 1002 is connected to one end of the switch matrix 1001, and the other end of the failure detection unit 1002 is connected to the grounding node. The failure detection unit 1002 is used to detect the components in the fuel cell system that are in a functionally failed state; One end of the insulation detection unit 1003 is respectively connected to one end of the switch matrix 1001 and one end of the failure detection unit 1002, and the other end of the insulation detection unit 1003 is connected to the grounding node. The insulation detection unit 1003 is used to detect the components in the fuel cell system that are in an insulation failure state.

[0052] That is to say, the switch matrix 1001 has multiple switch states, and these states correspond to different troubleshooting requirements. According to the current troubleshooting requirement, the switch matrix 1001 can adjust the connection state between the multiple troubleshooting nodes and the multiple points to be troubleshot, so as to implement various troubleshooting strategies; By measuring the electrical parameters (such as resistance, etc.) between the failure detection unit 1002 and the grounding node, it can be judged which components have failed functionally; By real-time monitoring parameters such as the insulation resistance between the insulation monitoring unit 1003 and the grounding node, it can be further determined whether the components with functional failure are in insulation failure.

[0053] Among them, in some embodiments, the switch matrix 1001 includes: the first to the Nth switches. One ends of the first to the Nth switches are all connected to one end of the failure detection unit 1002 and one end of the insulation detection unit 1003, and the other ends of the first to the Nth switches are connected to multiple points to be troubleshot in the fuel cell system through multiple troubleshooting nodes in one-to-one correspondence. The control ends of the first to the Nth switches are respectively connected to the control component 200.

[0054] For example, such as Figure 4As shown, the switch matrix 1001 may include a first switch K1, a second switch K2, a third switch K3, a fourth switch K4, and a fifth switch K5. One ends of the first to fifth switches K1-K5 are all connected to one end of the failure detection unit 1002 and one end of the insulation detection unit 1003. The other ends of the first to fifth switches K1-K5 are respectively connected to multiple points to be checked of the fuel cell system through multiple troubleshooting nodes. That is, the first switch K1 is connected to the resistance R110 of the point to be checked of the water pump interface pipeline through the troubleshooting node, the second switch K2 is connected to the resistance R105 of the point to be checked of the PTC interface pipeline through the troubleshooting node, the third switch K3 is connected to the resistance R102 of the point to be checked of the stack interface pipeline through the troubleshooting node, the fourth switch K4 is connected to the resistance R108 of the point to be checked of the radiator interface pipeline through the troubleshooting node, and the fifth switch K5 is connected to the resistance R104 of the point to be checked of the thermostat interface pipeline through the troubleshooting node. The control ends of the first to fifth switches K1-K5 are respectively connected to the control component 200, and the control component 200 is used to perform gating control on the first to fifth switches K1-K5.

[0055] Optionally, in some embodiments, the failure detection unit 1002 includes: a first resistor R1 and an (N + 1)-th switch. One end of the first resistor R1 is connected to the grounding node; one end of the (N + 1)-th switch is connected to the other end of the first resistor R1, the other end of the (N + 1)-th switch is connected to one ends of the first to N-th switches, and the control end of the (N + 1)-th switch is connected to the control component 200.

[0056] For example, as Figure 4 shown, the failure detection unit 1002 may include a first resistor R1 and a sixth switch K6. The first resistor R1 is a low-resistance resistor. One end of the first resistor R1 is connected to the grounding node and is used to detect whether there are components in a functional failure state in the cooling circuit of the fuel cell system. One end of the sixth switch K6 is connected to the other end of the first resistor R1, the other end of the sixth switch K6 is connected to one ends of the first to fifth switches K1-K5, and the control end of the sixth switch K6 is connected to the control component 200. The control component 200 is used to perform on-off control on the sixth switch K6.

[0057] It can be understood that the first resistor R1 (low-resistance resistor) is mainly used to initially troubleshoot the functional failure of the components in the cooling circuit. When the resistance value of the first resistor R1 is detected to be abnormal, it can be initially determined that the component stack in the cooling circuit has a functional failure.

[0058] Optionally, in some embodiments, the insulation detection unit 1003 includes: a second resistor R2 and an (N + 2)-th switch. One end of the second resistor R2 is connected to the grounding node; one end of the (N + 2)-th switch is connected to the other end of the second resistor R2, the other end of the (N + 2)-th switch is connected to one ends of the first to N-th switches, and the control end of the (N + 2)-th switch is connected to the control component 200.

[0059] For example, as Figure 4 shown, the insulation detection unit 1003 may include a second resistor R2 and a seventh switch K7. Among them, the second resistor R2 is a high-resistance resistor. One end of the second resistor R2 is connected to the grounding node and is used to detect whether there are components in an insulation failure state in the cooling circuit of the fuel cell system. One end of the seventh switch K7 is connected to the other end of the second resistor R2, the other end of the seventh switch K7 is connected to one ends of the first to fifth switches K1 to K5, and the control end of the seventh switch K7 is connected to the control component 200. The on / off control of the seventh switch K7 is performed by the control component 200.

[0060] It can be understood that after initially determining that there are components with functional failures in the cooling circuit through the first resistor R1, the second resistor R2 (high-resistance resistor) can be used to further check whether the components with functional failures are in an insulation failure state. When it is detected that the resistance value of the second resistor R2 is abnormal, then it can be determined that the insulation fault is the insulation failure of the cooling circuit.

[0061] Among them, both the first resistor R1 and the second resistor R2 are grounding resistors. A metal groundable inspection node is provided at the port of the cooling circuit component for connecting the first resistor R1 and the second resistor R2 to judge the insulation failure condition of the cooling circuit component.

[0062] Next, how to perform insulation failure fault diagnosis according to the fault detection component 100 will be described in detail.

[0063] Specifically, Figure 5An exemplary electrical framework schematic diagram of the fuel cell system according to an embodiment of the present application is presented, including: a fuel cell system and a power battery. Among them, the fuel cell system includes a stack, a fuel cell system power distribution unit, a PTC heater, a water pump, and a heat dissipation system. When the current insulation value of the fuel cell system detected by the insulation detector is less than or equal to a preset fault insulation value, it indicates that there is an insulation fault in the fuel cell system. After the fault is triggered, first confirm whether there is an insulation failure fault in the cooling circuit. First, select a component (such as the stack) in the cooling circuit, and then control the sixth switch K6 to close through the control component 200 and detect its insulation value. When the insulation value of the first resistor R1 is abnormal (such as the insulation value of the first resistor R1 is close to or the same as the current insulation value of the fuel cell system detected above (that is, the deviation does not exceed 10%)), it can be preliminarily determined that the component (such as the stack) in the cooling circuit is in a functional failure state. Further, control the seventh switch K7 to close through the control component 200 and detect its insulation value. When the insulation value of the second resistor R2 is abnormal (such as the insulation value of the second resistor R2 is close to or the same as the current insulation value of the fuel cell system detected above (that is, the deviation does not exceed 10%)), then it can be determined that the insulation fault of the fuel cell system is the insulation failure of this cooling circuit, and the specific component with insulation failure is the stack. Similarly, the next component can be selected and the insulation fault detection can be carried out in turn until all components in the cooling circuit are confirmed to be completed.

[0064] If it is determined that there is no insulation failure fault in the cooling circuit after all components in the cooling circuit are confirmed, then further confirm whether there is an insulation failure fault in the high-voltage circuit.

[0065] Further, the fault diagnosis component can be used to troubleshoot each component in the high-voltage circuit in sequence. For example, first disconnect the high-voltage connector of the water pump, control the first switch K1 to disconnect through the control component 200, and detect the insulation value of the resistance R110 at the point to be troubleshot on the water pump interface pipeline. If the insulation value of the resistance R110 at the point to be troubleshot on the water pump interface pipeline is close to or the same as the current insulation value of the fuel cell system detected above (i.e., the deviation does not exceed 10%), it is determined that the water pump has an insulation failure fault; otherwise, restore the high-voltage connector of the water pump, disconnect the high-voltage connector of the PTC, control the second switch K2 to disconnect through the control component 200, and detect the insulation value of the resistance R105 at the point to be troubleshot on the PTC interface pipeline. If the insulation value of the resistance R105 at the point to be troubleshot on the PTC interface pipeline is close to or the same as the current insulation value of the fuel cell system detected above, it is determined that the PTC has an insulation failure fault; otherwise, restore the high-voltage connector of the PTC, disconnect the high-voltage connector of the radiator, control the fourth switch K4 to disconnect through the control component 200, and detect the insulation value of the resistance R108 at the point to be troubleshot on the radiator interface pipeline. If the insulation value of the resistance R108 at the point to be troubleshot on the radiator interface pipeline is close to or the same as the current insulation value of the fuel cell system detected above, it is determined that the radiator has an insulation fault; otherwise, restore the radiator connector, disconnect the high-voltage connector of the thermostat, control the fifth switch K5 to disconnect through the control component 200, and detect the insulation value of the resistance R104 at the point to be troubleshot on the thermostat interface pipeline. If the insulation value of the resistance R104 at the point to be troubleshot on the thermostat interface pipeline is close to or the same as the current insulation value of the fuel cell system detected above, it is determined that the thermostat has an insulation fault; otherwise, it is directly determined that there is an insulation failure fault inside the fuel cell system DCDC (Direct Current - Direct Current, converter).

[0066] Thus, when there is an insulation failure fault in the fuel cell system, it can be accurately identified whether the insulation failure fault of the fuel cell system is caused by the insulation failure of the cooling circuit or the insulation failure of the high-voltage circuit, and after the insulation failure, it can also be accurately identified whether it is the insulation failure inside the power distribution unit of the fuel cell system or the insulation failure of the fuel cell stack.

[0067] Optionally, in some embodiments, the control component 200 includes: the first to the M + 2 control units, and the first to the M + 2 control units are respectively connected to one end of the first to the N + 2 switches in one-to-one correspondence.

[0068] For example, such as Figure 4As shown in the figure, the control component 200 may include a plurality of control units (such as the first to seventh control units C1 to C7). Each control unit is respectively and correspondingly connected to one end of the first to fifth switches K1 to K5 in the switch matrix 1001, the sixth switch K6 in the failure detection unit 1002, and the seventh switch K7 in the insulation detection unit, so as to control the connection state of the switches.

[0069] Optionally, in some embodiments, the first to N+2 switches are MOS transistors.

[0070] It can be understood that a MOS transistor is an electronic switch that controls current through voltage. It includes three electrodes: a source, a gate, and a drain. When an appropriate voltage is applied to the gate, it can form a conductive channel between the source and the drain, allowing current to pass through. Combining low-resistance and high-resistance testing methods, MOS transistors can be used to detect and isolate faulty components. For example, by controlling the switching state of specific MOS transistors, the resistance and insulation performance of related components can be tested.

[0071] According to the insulation fault diagnosis system of the fuel cell system proposed in the embodiments of the present application, the fault troubleshooting component adjusts the connection state between a plurality of troubleshooting nodes and a plurality of points to be troubleshot according to the current troubleshooting requirements; the control component sends the current troubleshooting requirements to the fault troubleshooting component, and after the fault troubleshooting component adjusts the connection state between the plurality of troubleshooting nodes and the plurality of points to be troubleshot, determines the components in the fuel cell system in an insulation failure state according to the troubleshooting results of each point to be troubleshot; the display component displays the components in the insulation failure state. Thus, through this insulation fault diagnosis system, the problems in the prior art that it is impossible to automatically locate specific faulty components during insulation fault diagnosis and to distinguish whether the insulation fault is caused by a high-voltage circuit failure or a cooling circuit failure can be solved, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0072] Secondly, the embodiments of the present application provide a fuel cell system, and the fuel cell system includes the insulation fault diagnosis system of the fuel cell system described above.

[0073] According to the fuel cell system proposed in the embodiments of the present application, through the insulation fault diagnosis system of the fuel cell system described above, the problems in the prior art that it is impossible to automatically locate specific faulty components during insulation fault diagnosis and to distinguish whether the insulation fault is caused by a high-voltage circuit failure or a cooling circuit failure can be solved, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0074] The embodiments of the present application also provide a vehicle, and the vehicle includes the fuel cell system described above.

[0075] According to the vehicle provided by the embodiments of the present application, through the above fuel cell system, it is possible to solve the problems in the prior art that when performing insulation fault diagnosis, it is impossible to automatically locate the specific faulty component, and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0076] The following describes an insulation fault diagnosis method for a fuel cell system according to an embodiment of the present application with reference to the accompanying drawings.

[0077] Figure 6 It is a flowchart of an insulation fault diagnosis method for a fuel cell system according to an embodiment of the present application.

[0078] As Figure 6 shown, the insulation fault diagnosis method of the fuel cell system adopts the insulation fault diagnosis system of the fuel cell system as in Figure 1 the embodiment, wherein the method includes the following steps:

[0079] In step S601, obtain the physical parameters of at least one component of the fuel cell system, calculate the theoretical insulation value of the fuel cell system at different conductivities based on a preset conductivity formula and the physical parameters, and determine a preset fault insulation value based on the theoretical insulation values at different conductivities.

[0080] Specifically, based on the physical parameters of at least one component of the fuel cell system and the preset conductivity formula, the theoretical insulation value of the fuel cell system at different conductivities can be calculated, and at the same time, the theoretical insulation value when the conductivity is 5 is set as the preset fault insulation value a for fault alarm prompt.

[0081] Among them, the preset conductivity formula is:

[0082]

[0083] Among them, R is the pipeline resistance, L is the pipeline length, S is the internal cross-sectional area of the pipeline, σ is the conductivity of the fuel cell system, and can be obtained by a conductivity meter on the fuel cell system.

[0084] In step S602, detect the current insulation value of the fuel cell system, and when the current insulation value is less than or equal to the preset fault insulation value, perform a fault check on each component in the cooling circuit through a fault troubleshooting component to determine whether the cooling circuit has an insulation failure.

[0085] Specifically, using a vehicle insulation detector can detect the current insulation value of the fuel cell system, and conduct a preliminary assessment of the insulation performance of the fuel cell system. The higher the insulation value, the better the insulation performance. By comparing the current insulation value with a preset fault insulation value, it is confirmed whether there is an insulation fault in the fuel cell system. When the current insulation value of the fuel cell system is less than or equal to the preset fault insulation value, it indicates that there is an insulation fault in the fuel cell system, and it is necessary to further conduct an insulation fault investigation on each component of the cooling circuit in sequence through a fault investigation component to determine whether the cooling circuit has insulation failure. That is, first select a component of the cooling circuit (such as the fuel cell stack), then select a first resistor (low-resistance resistor) inside the fault investigation component and detect the insulation value of the first resistor, and compare the insulation value of the first resistor with the current insulation value of the fuel cell system detected above to further determine whether the insulation performance of the grounding resistor is consistent with the insulation performance of the fuel cell system, so as to determine whether there is an insulation failure fault in the cooling circuit.

[0086] In step S603, if the cooling circuit has insulation failure, determine the component in the insulation failure state corresponding to the time when the cooling circuit has insulation failure; otherwise, conduct a fault investigation on each component in the high-voltage circuit through a fault investigation component to determine whether the high-voltage circuit has insulation failure and determine the component in the insulation failure state corresponding to the time when the high-voltage circuit has insulation failure.

[0087] Specifically, if the insulation value of the first resistor deviates by 10% compared with the current insulation value of the fuel cell system detected above, it indicates that the currently selected component is normal; on the contrary, if the insulation value of the first resistor is close to or the same as the current insulation value of the fuel cell system detected above (that is, the deviation does not exceed 10%), it indicates that the currently selected component is in a functional failure state, then further select a second resistor (high-resistance resistor) and detect the insulation value of the second resistor, and compare the insulation value of the second resistor with the current insulation value of the fuel cell system detected above. If the insulation value of the second resistor is close to or the same as the current insulation value of the fuel cell system detected above (that is, the deviation does not exceed 10%), it indicates that the currently selected component is in an insulation failure state, and so on. After detecting the currently selected component, select the next component of the cooling circuit and repeat the above process until all components of the cooling circuit are confirmed to be completed, thereby determining the components in the insulation failure state in the cooling circuit.

[0088] After all components in the cooling circuit are confirmed to be completed, if it is determined that the cooling circuit has not failed in insulation, the troubleshooting component will sequentially troubleshoot each component in the high-voltage circuit to determine whether the high-voltage circuit has failed in insulation. That is, first disconnect the high-voltage connector of a certain component (such as the high-voltage connector of the water pump) and detect the insulation value at the disconnected position. If the insulation value at the disconnected position deviates by 10% compared to the current insulation value of the fuel cell system detected above, it indicates that the component at the disconnected position is in a state of insulation failure. On the contrary, if the insulation value at the disconnected position is close to or the same as the current insulation value of the fuel cell system detected above (that is, the deviation does not exceed 10%), it indicates that the component at the disconnected position is normal, and its high-voltage connection is restored. And so on, disconnect the high-voltage connector of the next component and repeat the above process until all components in the high-voltage circuit are confirmed to be completed, thereby determining the components in the high-voltage circuit that are in a state of insulation failure.

[0089] It should be noted that after all components in the high-voltage circuit are confirmed to be completed, if it is determined that the high-voltage circuit has not failed in insulation either, it can be directly determined that there is an insulation failure fault inside the DCDC of the fuel cell system.

[0090] To facilitate those skilled in the art to further understand the insulation fault diagnosis method of the fuel cell system proposed in the embodiments of the present application, the following will be further elaborated in combination with Figure 7 for further elaboration.

[0091] As Figure 7 shown, the insulation fault diagnosis method of the fuel cell system may include the following steps:

[0092] Step 701, detecting the current insulation value of the fuel cell system.

[0093] Step 702, determining whether the current insulation value is less than or equal to the preset fault insulation value a. If so, execute Step 703; otherwise, execute Step 701.

[0094] Step 703, selecting and enabling the component stack in the troubleshooting component.

[0095] Step 704, selecting and enabling the low-resistance resistor in the troubleshooting component and detecting its insulation value.

[0096] Step 705, determining whether the insulation value of the low-resistance resistor deviates from the current insulation value of the fuel cell system by 10%. If so, execute Step 706; otherwise, prompt the fault location.

[0097] Step 706, selecting and enabling the high-resistance resistor in the troubleshooting component and recording its insulation value.

[0098] Step 707: Determine whether the insulation value of the high-resistance resistor deviates from the current insulation value of the fuel cell system by 10%. If so, execute Step 708; otherwise, prompt the location of the fault.

[0099] Step 708: Select the next component in the fault troubleshooting component.

[0100] Step 709: Determine that the cooling circuit is not insulation-failed, and further confirm whether it is the high-voltage circuit that is insulation-failed.

[0101] Step 710: Disconnect the high-voltage connector of the water pump and detect the insulation value.

[0102] Step 711: Determine whether this insulation value deviates from the current insulation value of the fuel cell system by 10%. If so, prompt the location of the fault; otherwise, execute Step 712.

[0103] Step 712: Restore the high-voltage connector of the water pump, disconnect the high-voltage connector of the PTC, and detect the insulation value.

[0104] Step 713: Determine whether this insulation value deviates from the current insulation value of the fuel cell system by 10%. If so, prompt the location of the fault; otherwise, execute Step 714.

[0105] Step 714: Restore the high-voltage connector of the PTC, disconnect the high-voltage connector of the heat dissipation system, and detect the insulation value.

[0106] Step 715: Determine whether this insulation value deviates from the current insulation value of the fuel cell system by 10%. If so, prompt the location of the fault; otherwise, execute Step 716.

[0107] Step 716: Determine that there is an insulation fault inside the DCDC.

[0108] According to the insulation fault diagnosis method of the fuel cell system proposed in the embodiments of the present application, it can solve the problems that in the prior art, when performing insulation fault diagnosis, it is impossible to automatically locate the specific faulty component, and it is impossible to distinguish whether the insulation fault is caused by the failure of the high-voltage circuit or the cooling circuit, accurately locate the source of the insulation problem, reduce the problem location time, and improve the service efficiency.

[0109] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0110] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0111] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. An insulation fault diagnosis system for a fuel cell system, characterized in that: include: A troubleshooting component (100), a control component (200) and a display component (300), wherein: The fault troubleshooting component (100) comprises a plurality of troubleshooting nodes, each of which is connected to a plurality of points to be troubleshooted of the fuel cell system in a one-to-one correspondence, and is used to adjust the connection status between the plurality of troubleshooting nodes and the plurality of points to be troubleshooted according to current troubleshooting requirements; The control component (200) is respectively connected to the multiple troubleshooting nodes, and is used to send the current troubleshooting requirement to the fault troubleshooting component (100), and after the fault troubleshooting component (100) adjusts the connection state between the multiple troubleshooting nodes and the multiple points to be checked based on the current troubleshooting requirement, determine the component in the fuel cell system that is in an insulation failure state according to the troubleshooting result of each point to be checked; The display component (300) is connected to the control component (200) and is used to display components in the fuel cell system that are in an insulation failure state.

2. The insulation fault diagnosis system of the fuel cell system according to claim 1, characterized in that: The fault troubleshooting component (100) comprises: A switch matrix (1001), one end of the switch matrix (1001) is connected to the control component (200), the other end of the switch matrix (1001) is connected to the multiple points to be checked of the fuel cell system through the multiple check nodes in a one-to-one correspondence, the switch matrix (1001) has multiple switch states, the multiple switch states correspond to multiple check requirements, and the switch matrix (1001) adjusts the connection state between the multiple check nodes and the multiple points to be checked according to the current check requirements; a failure detection unit (1002), one end of the failure detection unit (1002) being connected to one end of the switch matrix (1001), and the other end of the failure detection unit (1002) being connected to a ground node, and the failure detection unit (1002) being used to detect components in a functional failure state in the fuel cell system; An insulation detection unit (1003), one end of the insulation detection unit (1003) is respectively connected to one end of the switch matrix (1001) and one end of the failure detection unit (1002), and the other end of the insulation detection unit (1003) is connected to the ground node. The insulation detection unit (1003) is used to detect components in the fuel cell system that are in the insulation failure state.

3. The insulation fault diagnosis system of the fuel cell system according to claim 2, characterized in that: The switch matrix (1001) comprises: first to Nth switches, wherein: One end of each of the first to Nth switches is connected to one end of the failure detection unit (1002) and one end of the insulation detection unit (1003); the other end of each of the first to Nth switches is connected one-to-one with a plurality of points to be checked in the fuel cell system through the plurality of check nodes; and the control ends of the first to Nth switches are respectively connected to the control component (200).

4. The insulation fault diagnosis system of the fuel cell system according to claim 3, characterized in that: The failure detection unit (1002) comprises: a first resistor (R1), one end of the first resistor (R1) being connected to the ground node; An N+1th switch, one end of the N+1th switch is connected to the other end of the first resistor (R1), the other end of the N+1th switch is connected to one end of the first to Nth switches, and the control end of the N+1th switch is connected to the control component (200).

5. The insulation fault diagnosis system of the fuel cell system according to claim 4, characterized in that: The insulation detection unit (1003) comprises: a second resistor (R2), one end of the second resistor (R2) being connected to the ground node; An N+2th switch, one end of the N+2th switch is connected to the other end of the second resistor (R2), the other end of the N+2th switch is connected to one end of the first to Nth switches, and the control end of the N+2th switch is connected to the control component (200).

6. The insulation fault diagnosis system of the fuel cell system according to claim 5, characterized in that: The control component (200) comprises: The first to M+2th control units are respectively connected to one end of the first to N+2th switches in a one-to-one correspondence.

7. The insulation fault diagnosis system of the fuel cell system according to claim 5, characterized in that: The first to N+2 th switches are MOS tubes.

8. A fuel cell system, characterized in that: include: An insulation fault diagnosis system for a fuel cell system as claimed in any one of claims 1 to 7.

9. A vehicle, characterized in that: include: The fuel cell system as claimed in claim 8.

10. A method for diagnosing insulation faults in a fuel cell system, characterized in that: The insulation fault diagnosis system of the fuel cell system according to any one of claims 1 to 7 is adopted, wherein the method comprises the following steps: Acquiring physical parameters of at least one component of the fuel cell system, calculating theoretical insulation values ​​of the fuel cell system at different conductivities based on a preset conductivity formula and the physical parameters, and determining preset fault insulation values ​​based on the theoretical insulation values ​​at different conductivities; Detecting a current insulation value of the fuel cell system, and when the current insulation value is less than or equal to the preset fault insulation value, performing fault detection on each component in the cooling circuit through the fault detection component to determine whether the insulation of the cooling circuit fails; If the insulation of the cooling circuit fails, the corresponding components in the insulation failure state when the insulation of the cooling circuit fails are determined; otherwise, each component in the high-voltage circuit is troubleshooted through the fault detection component to determine whether the insulation of the high-voltage circuit fails and to determine the corresponding components in the insulation failure state when the insulation of the high-voltage circuit fails.

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