Cooling liquid shortage detection method and device, vehicle and storage medium

Abstract

The invention provides a cooling liquid shortage detection method and device, a vehicle and a storage medium, the method is applied to the vehicle, and the method comprises the steps that the cooling liquid temperature of a cooling liquid loop, the throttle valve opening degree and the water pump rotating speed are obtained; calculating the reference pressure of the coolant loop according to at least one of the coolant temperature, the throttle valve opening degree and the water pump rotating speed; and detecting the liquid shortage risk of the cooling liquid in the cooling liquid loop according to the reference pressure. According to the method, the situation that the liquid shortage risk is judged directly based on the pressure obtained by the pressure sensor, and consequently the liquid shortage risk judgment accuracy is low can be avoided, and the liquid shortage risk judgment accuracy is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicles, and more particularly, to a coolant liquid deficiency detection method and device, a vehicle and a storage medium. BACKGROUND

[0002] The thermal management module is an important part of the development of fuel cell system control. Too high a temperature can cause our stack to burn, and too low a temperature can affect the efficiency of our system power output.

[0003] The fuel cell thermal management system mainly includes a circulating water pump, a cooling fan, a thermostat valve and some temperature and pressure sensors. When performing thermal management control, it is necessary to first ensure that there is no liquid deficiency or leakage phenomenon, which is also a prerequisite for the control strategy to work. It has great limitations to determine whether there is a liquid deficiency based only on the water pressure signal collected by the sensor. The water pressure signal is affected by many factors. If only the sensor is used for judgment, frequent faults will occur, which not only affects the driving experience, but also causes a lot of unnecessary hydrogen consumption due to frequent system startup and shutdown.

[0004] At present, the pressure sensor signal is mainly used to determine the pressure value in the fuel cell system, and then remind the driver whether there is a liquid deficiency to check. However, due to the influence of various factors, it is often not accurate to determine whether there is a liquid deficiency. SUMMARY

[0005] The present application provides a coolant liquid deficiency detection method, device, vehicle and storage medium. The method can calculate the reference pressure of the coolant liquid according to at least one of the coolant liquid temperature, the throttle valve opening degree and the water pump speed, and further determine the liquid deficiency risk of the coolant liquid in the coolant liquid circuit according to the reference pressure, so as to avoid the low accuracy of the liquid deficiency risk judgment caused by directly judging the liquid deficiency risk based on the pressure obtained by the pressure sensor, and improve the accuracy of the liquid deficiency risk judgment.

[0006] In a first aspect, a coolant liquid deficiency detection method is provided. The method includes: obtaining the coolant liquid temperature, the throttle valve opening degree and the water pump speed of the coolant liquid circuit; calculating the reference pressure of the coolant liquid circuit according to at least one of the coolant liquid temperature, the throttle valve opening degree and the water pump speed; and detecting the liquid deficiency risk of the coolant liquid in the coolant liquid circuit according to the reference pressure.

[0007] Through the above technical solution, the present application can calculate the reference pressure of the coolant liquid according to at least one of the coolant liquid temperature, the throttle valve opening degree and the water pump speed, and further determine the liquid deficiency risk of the coolant liquid in the coolant liquid circuit according to the reference pressure, so as to avoid the low accuracy of the liquid deficiency risk judgment caused by directly judging the liquid deficiency risk based on the pressure obtained by the pressure sensor, and improve the accuracy of the liquid deficiency risk judgment.

[0008] With reference to the first aspect, in some possible implementation manners, the calculating the reference pressure of the cooling liquid circuit according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed comprises: obtaining first to third pressure relationship tables, wherein the first relationship table is a relationship between the cooling liquid temperature and a first pressure of the cooling liquid circuit, the second relationship table is a relationship between the throttle valve opening degree and a second pressure of the cooling liquid circuit, and the third pressure relationship table is a relationship between the water pump rotating speed and a third pressure of the cooling liquid circuit; querying the first pressure relationship table to obtain the first pressure by taking the cooling liquid temperature as an index; querying the second pressure relationship table to obtain the second pressure by taking the throttle valve opening degree as an index; querying the third pressure relationship table to obtain the third pressure by taking the water pump rotating speed as an index; and calculating the reference pressure of the cooling liquid circuit according to the first pressure, the second pressure and the third pressure.

[0009] Through the technical solution, the first pressure, the second pressure and the third pressure can be obtained based on the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed by indexing the corresponding pressure relationship tables, and the reference pressure of the cooling liquid circuit can be calculated based on the first pressure, the second pressure and the third pressure.

[0010] With reference to the first aspect and the implementation manners, in some possible implementation manners, the detecting the liquid deficiency state of the cooling liquid in the cooling liquid circuit according to the reference pressure comprises: obtaining a stack inlet pressure of the fuel cell; calculating a pressure error between the stack inlet pressure and the reference pressure; and determining that there is a liquid deficiency risk of the cooling liquid in the cooling liquid circuit if the pressure error is greater than a preset error.

[0011] Through the technical solution, when the pressure error between the stack inlet pressure of the fuel cell and the reference pressure is greater than a preset error, it is determined that there is a liquid deficiency risk of the cooling liquid in the cooling liquid circuit, because the error is large, which indicates that the stack inlet pressure is monitored incorrectly.

[0012] With reference to the first aspect and the implementation manners, in some possible implementation manners, before the detecting the liquid deficiency risk of the cooling liquid in the cooling liquid circuit according to the reference pressure, the method further comprises: obtaining an ambient atmospheric pressure; and correcting the reference pressure according to the ambient atmospheric pressure.

[0013] Through the technical solution, because the ambient atmospheric pressure has an influence on the pressure of the cooling circuit, the reference pressure can be corrected according to the ambient atmospheric pressure before the detecting the liquid deficiency risk of the cooling liquid in the cooling liquid circuit according to the reference pressure.

[0014] In a possible implementation manner, before the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed of the cooling liquid circuit are acquired, the method further includes: detecting a current state of the thermal management system of the vehicle; if the current state is a running state, acquiring the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed of the cooling liquid circuit; and if the current state is a non-running state, identifying a target fault of the cooling circuit according to the stack inlet pressure and the ambient atmospheric pressure.

[0015] According to the technical solution, if the current state of the thermal management system is a running state, the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed of the cooling liquid circuit are acquired, otherwise, a target fault of the cooling circuit is directly identified according to the stack inlet pressure and the ambient atmospheric pressure.

[0016] In a possible implementation manner, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure, including: calculating a pressure difference value of the stack inlet pressure and the ambient atmospheric pressure; and if, in a continuous first preset number of driving cycles, a number of pressure difference values greater than a preset difference value exceeds a second preset number, identifying that the target fault is an expansion tank or a water overflow pot related fault.

[0017] According to the technical solution, if, in a continuous first preset number of driving cycles, a number of pressure difference values greater than a preset difference value exceeds a second preset number, it is determined that the target fault is an expansion tank or a water overflow pot related fault.

[0018] In a possible implementation manner, before the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure, the method further includes: acquiring a standby duration of the thermal management system; and if the standby duration is greater than a preset duration, identifying the target fault of the cooling circuit according to the stack inlet pressure and the ambient atmospheric pressure.

[0019] According to the technical solution, after the standby duration of the thermal management system is greater than a preset duration, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure, so as to avoid that the temperature is too high when the system is shut down and the fault cannot be directly identified.

[0020] In a second aspect, a cooling liquid shortage detection device is provided, including: an acquisition module, configured to acquire a cooling liquid temperature, a throttle valve opening degree and a water pump rotating speed of a cooling liquid circuit; a calculation module, configured to calculate a reference pressure of the cooling liquid circuit according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed; and a detection module, configured to detect a shortage risk of the cooling liquid in the cooling liquid circuit according to the reference pressure.

[0021] With reference to the second aspect, in some possible implementation manners, the calculating module is further configured to: obtain the first pressure relationship table, the second pressure relationship table and the third pressure relationship table, where the first relationship table is a relationship between the coolant temperature and the first pressure of the coolant circuit, the second relationship table is a relationship between the throttle valve opening and the second pressure of the coolant circuit, and the third pressure relationship table is a relationship between the water pump rotating speed and the third pressure of the coolant circuit; query the first pressure relationship table to obtain the first pressure by taking the coolant temperature as an index; query the second pressure relationship table to obtain the second pressure by taking the throttle valve opening as an index; query the third pressure relationship table to obtain the third pressure by taking the water pump rotating speed as an index; and calculate the reference pressure of the coolant circuit according to the first pressure, the second pressure and the third pressure.

[0022] With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the detecting module is further configured to: obtain the stack inlet pressure of the fuel cell; calculate a pressure error between the stack inlet pressure and the reference pressure; and determine that the coolant in the coolant circuit is at risk of liquid deficiency when the pressure error is greater than a preset error.

[0023] With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the method further includes: a correcting module configured to correct the reference pressure according to the ambient atmospheric pressure before detecting the liquid deficiency risk of the coolant in the coolant circuit according to the reference pressure.

[0024] With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the method further includes: an identifying module configured to detect a current state of the thermal management system of the vehicle before obtaining the coolant temperature, the throttle valve opening and the water pump rotating speed of the coolant circuit; obtain the coolant temperature, the throttle valve opening and the water pump rotating speed of the coolant circuit when the current state is a running state; and identify a target fault of the coolant circuit according to the stack inlet pressure and the ambient atmospheric pressure when the current state is a non-running state.

[0025] With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the identifying module is further configured to: calculate a pressure difference between the stack inlet pressure and the ambient atmospheric pressure; and identify that the target fault is an expansion tank or a water overflow pot related fault when, in a continuous first preset number of driving cycles, more than a second preset number of pressure difference values are greater than a preset difference value.

[0026] With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the identifying module is further configured to: obtain a standby duration of the thermal management system; and identify the target fault of the coolant circuit according to the stack inlet pressure and the ambient atmospheric pressure when the standby duration is greater than a preset duration.

[0027] In a third aspect, a vehicle is provided, and the vehicle includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the program to implement the method in the first aspect or any possible implementation manner of the first aspect.

[0028] In a fourth aspect, a computer readable storage medium is provided, and the computer readable storage medium stores a computer program, and when the computer program is executed, the method in the first aspect or any possible implementation manner of the first aspect is implemented. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a structural diagram of a heat management system in the related art;

[0030] Figure 2 is a flowchart of a cooling liquid shortage detection method according to an embodiment of the present application;

[0031] Figure 3 is a specific flowchart of a cooling liquid shortage detection method according to an embodiment of the present application;

[0032] Figure 4 is a schematic diagram of a cooling liquid shortage detection device according to an embodiment of the present application;

[0033] Figure 5 is a structural diagram of a vehicle according to an embodiment of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the present application will be described clearly and exhaustively below with reference to the drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " represents the meaning of or, for example, A / B can represent A or B: "and / or" in the text only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases of A alone, A and B together, and B alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0035] Hereinafter, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include one or more features.

[0036] Before explaining the cooling liquid shortage detection method provided by the embodiments of the present application, the working principle of the heat management system of the fuel cell system related to the embodiments of the present application is described, and the structure of the heat management system is as follows Figure 1The heat management system includes a circulating water pump, a heat dissipation fan, a thermostat valve, and some temperature and pressure sensors.

[0037] In the related art, the pressure sensor CPT signal is usually used to determine the pressure value, and then remind the driver whether the liquid is lacking or not to be checked, but due to the influence of various factors, it is often not accurate to reflect whether the liquid is lacking.

[0038] According to the polarization curve of the fuel cell system, the system power output is usually divided into three intervals: activation polarization, ohmic polarization, and concentration polarization. Generally, the fuel cell system is controlled to work in the ohmic polarization interval. In this interval, the main factor affecting the power output of the fuel cell system is the internal resistance of the stack, and the dryness of the membrane is a factor affecting the resistance. The heat management system mainly affects the dryness of the fuel cell system by controlling the temperature, thereby reducing the internal resistance of the stack when working in this interval to improve the efficiency of the fuel cell system.

[0039] Figure 2 is a schematic flowchart of a cooling liquid liquid deficiency detection method provided by the embodiment of the present application.

[0040] As shown in the figure, the cooling liquid liquid deficiency detection method includes the following steps: Figure 2

[0041] In step S101, the cooling liquid temperature, the throttle valve opening degree, and the water pump speed of the cooling liquid circuit are obtained.

[0042] It can be understood that the cooling liquid temperature Te, the throttle valve opening degree Op, and the water pump speed Sp of the cooling liquid circuit can be obtained in order to subsequently detect whether the cooling liquid is lacking.

[0043] It should be noted that the cooling liquid temperature Te: the cooling liquid is different from water, and as the temperature rises, the viscosity of the cooling liquid will gradually decrease, and the viscosity of the cooling liquid and the pressure are negatively correlated;

[0044] Throttle valve opening degree Op: in order to realize the system startup process fast warm-up and reduce unnecessary power consumption, a valve is generally used, which is also called small and large circulation. When the system starts, it generally runs in small circulation, and when it works normally, it generally runs in large circulation. The pressure of small and large circulation is different, and as the valve opening degree increases, the water pressure will also gradually increase.

[0045] Water pump speed Sp: in order to realize the circulation of antifreeze, a water pump is generally added in the heat management circuit, and as the water pump speed increases, the pressure of the circuit will also gradually increase.

[0046] ​In the embodiment of the present application, before the coolant temperature of the coolant circuit, the throttle valve opening degree and the water pump rotating speed are acquired, the current state of the thermal management system of the vehicle is detected; if the current state is a running state, the coolant temperature of the coolant circuit, the throttle valve opening degree and the water pump rotating speed are acquired; if the current state is a non-running state, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure.

[0047] It can be understood that the state of the thermal management system of the vehicle in the embodiment of the present application is divided into a running state run and a non-running state Nrun, when the thermal management system is in the run state, the coolant liquid shortage detection method of the present application is executed, otherwise, when the thermal management system is in the Nrun state, the target fault of the cooling circuit is directly identified according to the stack inlet pressure CPT and the ambient atmospheric pressure Atm, and the specific identification method is as follows.

[0048] It should be noted that the ambient atmospheric pressure: the outlet of the general cooling circuit has an expansion tank, when the pressure of the cooling circuit is too large, the air will be released, and when the pressure is too small, the air will be supplemented, but if the overflow pot or the expansion tank cannot work normally, the pressure of the water circuit will also be affected, so when the system does not work, the atmospheric pressure can be used to judge whether the pressure of the cooling circuit is normal.

[0049] In the embodiment of the present application, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure, comprising: calculating the pressure difference value of the stack inlet pressure and the ambient atmospheric pressure; if in a continuous first preset number of driving cycles, the pressure difference value is greater than a preset difference value for more than a second preset number of times, the target fault is identified as an expansion tank or overflow pot related fault.

[0050] Among them, the first preset number, the second preset number and the preset difference value can be set according to specific conditions, for example, the first preset number is 5 times, the second preset number is 3 times, and the preset difference value is 15kPa.

[0051] It can be understood that the pressure difference value of the stack inlet pressure CPT and the ambient atmospheric pressure Atm can be calculated, if in a continuous first preset number of driving cycles, if the number of times that the pressure difference value is greater than the preset difference value exceeds the second preset number, the fault of the cooling circuit is an expansion tank or overflow pot related fault.

[0052] In the embodiment of the present application, before the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure, the standby time length of the thermal management system is acquired; if the standby time length is greater than a preset time length, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure.

[0053] The preset time length can be set according to specific conditions, and the comparison is not specifically limited, for example, can be 10 min.

[0054] Since the temperature of the water is high and the pressure is too large after the heat management system is just powered off, it is impossible to make a judgment, therefore, the standby time length of the heat management system can be acquired, and after the standby time length is greater than the preset time length, the target fault of the cooling loop is identified according to the stack inlet pressure and the ambient pressure.

[0055] In step S102, the reference pressure of the cooling liquid loop is calculated according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed.

[0056] It can be understood that the reference pressure of the cooling liquid loop can be calculated according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed, so as to make a liquid deficiency risk judgment based on the reference pressure subsequently, and the specific calculation process is as follows.

[0057] In the embodiment of the application, the reference pressure of the cooling liquid loop is calculated according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed, including: acquiring first to third pressure relationship tables, wherein the first relationship table is the relationship between the cooling liquid temperature and the first pressure of the cooling liquid loop, the second relationship table is the relationship between the throttle valve opening degree and the second pressure of the cooling liquid loop, and the third pressure relationship table is the relationship between the water pump rotating speed opening degree and the third pressure of the cooling liquid loop; the first pressure is obtained by querying the first pressure relationship table with the cooling liquid temperature as the index; the second pressure is obtained by querying the second pressure relationship table with the throttle valve opening degree as the index; the third pressure is obtained by querying the third pressure relationship table with the water pump rotating speed as the index; and the reference pressure of the cooling liquid loop is calculated according to the first pressure, the second pressure and the third pressure.

[0058] It can be understood that the first pressure is obtained by querying the first pressure relationship table with the cooling liquid temperature as the index, the second pressure is obtained by querying the second pressure table with the throttle valve opening degree as the index, the third pressure is obtained by querying the third pressure relationship table with the water pump rotating speed as the index, and the reference pressure Pr of the cooling loop is further calculated according to the first pressure, the second pressure and the third pressure, wherein the calculation formula of the reference pressure is:

[0059]

[0060] Pr (run) is the reference pressure in the running state, C (Te:Sp) is the first pressure, C (Op:Sp) is the second pressure, C (Op:Te) is the third pressure, K Atm is the correction coefficient.

[0061] In step S103, the risk of liquid deficiency of the coolant in the coolant circuit is detected according to the reference pressure.

[0062] It can be understood that the embodiments of the present application can detect the risk of liquid deficiency of the coolant in the coolant circuit according to the reference pressure, so as to avoid the low accuracy of the risk of liquid deficiency caused by directly judging the risk of liquid deficiency according to the pressure obtained by the pressure sensor, and improve the accuracy of the liquid deficiency diagnosis.

[0063] In the embodiments of the present application, the liquid deficiency state of the coolant in the coolant circuit is detected according to the reference pressure, including: obtaining the stack inlet pressure of the fuel cell; calculating the pressure error of the stack inlet pressure and the reference pressure; and if the pressure error is greater than a preset error, it is determined that the coolant in the coolant circuit has a risk of liquid deficiency.

[0064] The preset error can be set according to specific conditions, for example, it can be set to 5%.

[0065] It can be understood that the embodiments of the present application can calculate the pressure error of the stack inlet pressure of the fuel cell and the reference pressure, and if the pressure error is greater than a preset error, it is determined that the coolant in the coolant circuit has a risk of liquid deficiency.

[0066] In the embodiments of the present application, before detecting the risk of liquid deficiency of the coolant in the coolant circuit according to the reference pressure, it also includes: obtaining the ambient atmospheric pressure; and correcting the reference pressure according to the ambient atmospheric pressure.

[0067] Since the ambient atmospheric pressure Atm also has an impact on the reference pressure Pr, the embodiments of the present application correct the reference pressure according to the ambient atmospheric pressure, so as to improve the calculation accuracy of the reference pressure, and further improve the accuracy of the liquid deficiency detection. For example, in the running state of the thermal management system, the influence of Atm on Pr is the smallest, so Atm is taken as the correction coefficient of the finally calculated Pr.

[0068] Specifically, the specific process of the coolant liquid deficiency detection method of the embodiments of the present application is as shown in Figure 3 , including:

[0069] 1. According to the vehicle end, the following signals are obtained: coolant circuit temperature Te, water pump speed Sp, ambient pressure Atm, and valve opening degree Op. The relatively accurate pressure signal Pr is simulated by the above signals, and then it is judged whether the coolant circuit is short of liquid.

[0070] 2. It is judged whether Te, Sp, Atm and Op are normal. If they are normal, the following steps are executed, otherwise the related signal faults are reported.

[0071] 3, The thermal management system is divided into run state and non-run state (Nrun), in the system run state, the influence of Atm on Pr is minimal, so Atm is taken as the final calculation of Pr correction coefficient, for Te, Sp, Op three factors, through the test way to get the normal work under the system parameter look-up table Control Map (hereinafter referred to as C, wherein C (Te:sp) represent the look-up table based on temperature and speed,

[0072]

[0073] Control map instance:

[0074] Keep Op unchanged, observe the influence of Te and Sp on the system pressure to get C (Te:Sp) Pressure signal, unit kPa, table 1 is based on temperature Te and water pump speed Sp to determine the pressure table.

[0075] Table 1

[0076]

[0077] 4, In Nrun state, there will be the following situations:

[0078] (1) After the thermal management system standby for a long time (the system actuators are all in the initial state and the coolant temperature is normal), when the difference between CPT and Atm is greater than 15 kPa, record once every driving cycle, if the difference is greater than 15 kPa for more than three times in five consecutive driving cycles, it may be related to the expansion tank or overflow jug, remind to check, and take the pressure difference between the two as the pressure in the subsequent run state;

[0079] (2) After the thermal management system is just turned off, the water temperature is still relatively high at this time, CPT12 is very large at this time, which cannot be judged.

[0080] 5, Compare the calculated Pr (run) with the actual CPT sensor signal at the entrance of the electric pile (i.e. the actual pressure), if the error is greater than 5%, it is considered that the system has a great risk of liquid deficiency, then the system alarms to remind the driver to check the coolant.

[0081] For example, table 2 is based on the coolant circuit temperature Te, water pump speed Sp, ambient pressure Atm, valve opening Op signal, reference pressure Pr, pressure sensor CPT signal for simple simulation, the pressure correction value range obtained by different combination of signals can be calculated by big data, table 2 is the deviation table under different signals.

[0082] Table 2

[0083]

[0084] According to the cooling liquid shortage detection method provided in the embodiments of the present application, the reference pressure of the cooling liquid can be calculated according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed, and the shortage risk of the cooling liquid in the cooling liquid circuit is further determined according to the reference pressure, so as to avoid the low accuracy of the shortage risk judgment caused by directly judging the shortage risk based on the pressure obtained by the pressure sensor, and improve the accuracy of the shortage risk judgment.

[0085] Figure 4 FIG. 1 is a structural schematic diagram of a cooling liquid shortage detection device provided in the embodiments of the present application.

[0086] For example, as shown in FIG. 1, the cooling liquid shortage detection device 10 can include an acquisition module 100, a calculation module 200 and a detection module 300, wherein, Figure 4 The acquisition module 100 is configured to acquire the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed of the cooling liquid circuit.

[0087] The calculation module 200 is configured to calculate the reference pressure of the cooling liquid circuit according to at least one of the cooling liquid temperature, the throttle valve opening degree and the water pump rotating speed.

[0088] The detection module 300 is configured to detect the shortage risk of the cooling liquid in the cooling liquid circuit according to the reference pressure.

[0089] In the embodiments of the present application, the calculation module 200 is further configured to acquire first to third pressure relationship tables, wherein the first relationship table is the relationship between the cooling liquid temperature and the first pressure of the cooling liquid circuit, the second relationship table is the relationship between the throttle valve opening degree and the second pressure of the cooling liquid circuit, and the third pressure relationship table is the relationship between the water pump rotating speed and the third pressure of the cooling liquid circuit; the first pressure is obtained by querying the first pressure relationship table with the cooling liquid temperature as an index; the second pressure is obtained by querying the second pressure relationship table with the throttle valve opening degree as an index; the third pressure is obtained by querying the third pressure relationship table with the water pump rotating speed as an index; and the reference pressure of the cooling liquid circuit is calculated according to the first pressure, the second pressure and the third pressure.

[0090] In the embodiments of the present application, the detection module 300 is further configured to acquire the stack inlet pressure of the fuel cell; calculate the pressure error between the stack inlet pressure and the reference pressure; and if the pressure error is greater than a preset error, it is determined that the cooling liquid in the cooling liquid circuit has a shortage risk.

[0091] In the embodiments of the present application, the device 10 provided in the embodiments of the present application further includes a correction module.

[0092]

[0093] ​The correction module is configured to correct the reference pressure according to the ambient atmospheric pressure before detecting the risk of liquid deficiency of the coolant in the coolant circuit according to the reference pressure.

[0094] In the embodiments of the present application, the device 10 further comprises an identification module.

[0095] The identification module is configured to detect a current state of the thermal management system of the vehicle before obtaining the coolant temperature, the throttle valve opening degree and the water pump rotating speed of the coolant circuit; if the current state is a running state, the coolant temperature, the throttle valve opening degree and the water pump rotating speed of the coolant circuit are obtained; and if the current state is a non-running state, the target fault of the cooling circuit is identified according to the stack inlet pressure and the ambient atmospheric pressure.

[0096] In the embodiments of the present application, the identification module is further configured to: calculate a pressure difference value of the stack inlet pressure and the ambient atmospheric pressure; and if the pressure difference value is greater than a preset difference value for more than a second preset number of times in a continuous first preset number of driving cycles, identify the target fault as an expansion tank or overflow jug related fault.

[0097] In the embodiments of the present application, the identification module is further configured to: calculate a pressure difference value of the stack inlet pressure and the ambient atmospheric pressure; and if the pressure difference value is greater than a preset difference value for more than a second preset number of times in a continuous first preset number of driving cycles, identify the target fault as an expansion tank or overflow jug related fault.

[0098] In the embodiments of the present application, the identification module is further configured to: obtain a standby duration of the thermal management system; and if the standby duration is greater than a preset duration, identify the target fault of the cooling circuit according to the stack inlet pressure and the ambient atmospheric pressure.

[0099] The coolant liquid deficiency detection device provided in the embodiments of the present application can calculate the reference pressure of the coolant according to at least one of the coolant temperature, the throttle valve opening degree and the water pump rotating speed, and further determine the risk of liquid deficiency of the coolant in the coolant circuit according to the reference pressure, so as to avoid the low accuracy of the risk of liquid deficiency caused by directly judging the risk of liquid deficiency based on the pressure obtained by the pressure sensor, and improve the accuracy of the risk of liquid deficiency.

[0100] Figure 5 A structural schematic diagram of a vehicle is provided in the embodiments of the present application. The vehicle can include:

[0101] The memory 501, the processor 502 and the computer program stored in the memory 501 and executable on the processor 502.

[0102] The processor 502 executes the program to implement the coolant liquid deficiency detection method provided in the above embodiments.

[0103] Further, the vehicle further comprises:

[0104] A communication interface 503 for communication between the memory 501 and the processor 502.

[0105] The memory 501 is configured to store a computer program executable by the processor 502.

[0106] The memory 501 can include a high-speed RAM (Random Access Memory) memory, and can further include a nonvolatile memory such as at least one disk memory.

[0107] If the memory 501, the processor 502 and the communication interface 505 are implemented independently, the communication interface 503, the memory 501 and the processor 502 can be connected to each other through a bus and complete communication between each other. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, Figure 5 In the figure, only one thick line is used to represent, but it does not mean that there is only one bus or one type of bus.

[0108] Optionally, in a specific implementation, if the memory 501, the processor 502 and the communication interface 503 are integrated on a chip, the memory 501, the processor 502 and the communication interface 503 can complete communication between each other through an internal interface.

[0109] The processor 502 can be a CPU (Central Processing Unit), or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present application.

[0110] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the above cooling liquid detection method.

[0111] In addition, the terms "first", "second", etc. are used only to describe purposes and can not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly and specifically limited.

[0112] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like 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 the present application. In the present application, the illustrative description of the above terms is not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0113] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and can not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A method for detecting coolant shortage, characterized in that, The method includes: Obtain the coolant temperature, throttle valve opening, and water pump speed in the coolant circuit; The reference pressure of the coolant circuit is calculated based on at least one of the coolant temperature, the throttle valve opening, and the water pump speed. The risk of coolant shortage in the coolant circuit is detected based on the reference pressure.

2. The method according to claim 1, characterized in that, The step of calculating the reference pressure of the coolant circuit based on at least one of the coolant temperature, the throttle valve opening, and the water pump speed includes: Obtain the first to third pressure relationship tables, wherein the first relationship table is the relationship between the coolant temperature and the first pressure of the coolant circuit, the second relationship table is the relationship between the throttle valve opening and the second pressure of the coolant circuit, and the third pressure relationship table is the relationship between the water pump speed opening and the third pressure of the coolant circuit; Using the coolant temperature as an index, the first pressure is obtained by querying the first pressure relationship table; Using the opening degree of the throttle valve as an index, the second pressure is obtained by querying the second pressure relationship table; Using the pump speed as an index, the third pressure is obtained by querying the third pressure relationship table; The reference pressure of the coolant circuit is calculated based on the first pressure, the second pressure, and the third pressure.

3. The method according to claim 1, characterized in that, The step of detecting the coolant shortage status of the coolant circuit based on the reference pressure includes: Obtain the inlet pressure of the fuel cell stack; Calculate the pressure error between the fuel cell stack inlet pressure and the reference pressure; If the pressure error is greater than the preset error, it is determined that there is a risk of coolant shortage in the coolant circuit.

4. The method according to any one of claims 1-3, characterized in that, Before detecting the risk of coolant shortage in the coolant circuit based on the reference pressure, the method further includes: Obtain ambient atmospheric pressure; The reference pressure is corrected based on the ambient atmospheric pressure.

5. The method according to claim 1, characterized in that, Before obtaining the coolant temperature, throttle valve opening, and water pump speed of the coolant circuit, the following steps are also included: Check the current status of the vehicle's thermal management system; If the current state is the running state, then obtain the coolant temperature, throttle valve opening and water pump speed of the coolant circuit; If the current state is a non-operational state, the target fault of the cooling circuit is identified based on the fuel cell inlet pressure and ambient atmospheric pressure.

6. The method according to claim 5, characterized in that, The method of identifying target faults in the cooling circuit based on the fuel cell inlet pressure and ambient atmospheric pressure includes: Calculate the pressure difference between the fuel cell stack inlet pressure and the ambient atmospheric pressure; If, in a first preset number of consecutive driving cycles, the pressure difference exceeds a preset value for more than a second preset number of cycles, then the target fault is identified as a fault related to the expansion tank or overflow tank.

7. The method according to claim 5 or 6, characterized in that, Before identifying the target fault in the cooling circuit based on the stack inlet pressure and ambient atmospheric pressure, the following steps are also included: Obtain the standby time of the thermal management system; If the standby time exceeds the preset time, the target fault of the cooling circuit is identified based on the fuel cell inlet pressure and ambient atmospheric pressure.

8. A coolant shortage detection device, characterized in that, The device includes: The acquisition module is used to acquire the coolant temperature, throttle valve opening, and water pump speed of the coolant circuit; The calculation module is used to calculate the reference pressure of the coolant circuit based on at least one of the coolant temperature, the throttle valve opening, and the water pump speed; The detection module is used to detect the risk of coolant shortage in the coolant circuit based on the reference pressure.

9. A vehicle, characterized in that, The vehicle includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the coolant shortage detection method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the coolant shortage detection method as described in any one of claims 1-7.

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