Power control method, device, equipment and storage medium of fuel cell system

Abstract

The present application discloses a power control method, device, equipment and storage medium for a fuel cell system. The power control method for the fuel cell system includes: when the fuel cell system enters an idle condition and the current power demand of the vehicle controller is less than the idle power of the fuel cell system, entering a power regulation mode; adjusting the target current input to the DC converter according to the current power demand; reducing the target speed of the air compressor; adjusting the target opening of the stack entry shutoff valve according to the minimum value of the single-chip voltage of the stack; and exiting the power regulation mode when the current power demand is greater than or equal to the idle power. The technical solution of the present application can adjust the power output of the fuel cell system under idle conditions according to the current power demand of the vehicle controller, meet the various power requirements of the vehicle controller, and improve the applicability of the fuel cell system.

Description

Technical Field

[0001] The present application belongs to the field of fuel cell technology, and in particular, relates to a power control method, device, equipment and storage medium for a fuel cell system. Background Art

[0002] As the global requirements for carbon emissions become increasingly stringent, new energy vehicles have developed rapidly, and many countries have announced the time to ban the sale of fuel vehicles. In China, due to the guidance of national and local policies, new energy vehicles have made great progress. Fuel cell vehicles, as an important part of new energy vehicles, have also developed rapidly in recent years.

[0003] There are many technical difficulties in the promotion of fuel cell vehicles. For example, when the fuel cell system is running under idle conditions, its idle power not only needs to meet the power consumed by the system components itself, but also needs to meet the power output to the outside. However, the power of the fuel cell system under idle conditions is basically fixed and cannot meet the various power requests of the vehicle control unit (VCU). Summary of the invention

[0004] The embodiments of the present application provide a power control method, device, equipment and storage medium for a fuel cell system, which can adjust the power of the fuel cell system under idle conditions to meet various power requests of the vehicle VCU.

[0005] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0006] According to a first aspect of an embodiment of the present application, a power control method of a fuel cell system is provided, wherein the fuel cell system includes a fuel cell stack, a monolithic voltage patroller, a DC converter, an air compressor, and a stack entry shutoff valve, and the power control method of the fuel cell system includes:

[0007] When the fuel cell system enters an idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system, entering a power regulation mode;

[0008] Adjusting the target current output by the stack to the DC converter according to the current required power;

[0009] reducing a target speed of the air compressor;

[0010] adjusting the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack;

[0011] When a shutdown command is received or the current required power is not less than the idle power, the power adjustment mode is exited.

[0012] In some embodiments of the present application, based on the above solution, adjusting the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack includes:

[0013] Comparing the minimum value of the single-chip voltage of the battery stack with a preset single-chip voltage lower limit value and a preset single-chip voltage upper limit value respectively;

[0014] When the minimum value of the single chip voltage is less than the preset single chip voltage lower limit value, setting the target opening of the stack entry cut-off valve to the upper opening limit value of the stack entry cut-off valve;

[0015] When the minimum value of the single chip voltage is greater than the preset upper limit value of the single chip voltage, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

[0016] In some embodiments of the present application, based on the above solution, adjusting the target current output by the stack to the DC converter according to the current required power includes:

[0017] Searching for the current corresponding to the current required power from a preset mapping table, wherein the preset mapping table is used to characterize the corresponding relationship between the required power and the current output from the battery stack to the DC converter;

[0018] The target current is set to the found current.

[0019] In some embodiments of the present application, based on the above solution, reducing the target speed of the air compressor includes:

[0020] The target rotation speed is set to the minimum rotation speed of the air compressor.

[0021] In some embodiments of the present application, based on the above solution, the fuel cell system further includes a back pressure valve and a leakage valve, and the power control method further includes:

[0022] Setting the target opening of the back-pressure valve to the minimum opening of the back-pressure valve;

[0023] The target opening of the relief valve is set to a first preset value.

[0024] In some embodiments of the present application, based on the above solution, the fuel cell system further includes a hydrogen pump and a PID controller for adjusting air pressure and air flow, and the power control method further includes:

[0025] Setting the PID control parameters of the PID controller to zero;

[0026] The rotation speed of the hydrogen pump is controlled to be a second preset value.

[0027] In some embodiments of the present application, based on the above solution, before entering the power adjustment mode, the power control method further includes:

[0028] Determine a first time that the current required power is less than the idle power;

[0029] When the first time is greater than or equal to the first preset time, executing the step of entering the power adjustment mode;

[0030] Accordingly, before exiting the power regulation mode, the power control method further includes:

[0031] Determine a second time period during which the current required power is greater than or equal to the idle power;

[0032] When the second time is greater than or equal to a second preset time, the step of exiting the power adjustment mode is performed.

[0033] According to a second aspect of an embodiment of the present application, a power control device of a fuel cell system is provided, wherein the fuel cell system comprises a fuel cell stack, a monolithic voltage patroller, a DC converter, an air compressor, and a stack entry shutoff valve, and the power control device of the fuel cell system comprises:

[0034] A power regulation start unit, used to enter a power regulation mode when the fuel cell system enters an idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system;

[0035] a target current determination unit, configured to adjust a target current output by the battery stack to the DC converter according to the current required power;

[0036] a target speed determination unit, configured to reduce a target speed of the air compressor;

[0037] a target opening determination unit, configured to adjust the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack;

[0038] The power regulation shutdown unit is used to exit the power regulation mode when a shutdown command is received or the current required power is not less than the idle power.

[0039] According to a third aspect of an embodiment of the present application, a power control device of a fuel cell system is provided, wherein the power control device of the fuel cell system comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0040] According to a fourth aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0041] In the present application, when the fuel cell system enters the idle condition and the current power demand of the vehicle controller is less than the idle power of the fuel cell system, the power regulation mode is entered; the target current output by the fuel cell stack to the DC converter is adjusted according to the current power demand; the target speed of the air compressor is reduced; the target opening of the stack inlet shut-off valve is adjusted according to the minimum value of the single-chip voltage of the fuel cell stack; and the power regulation mode is exited when a shutdown command is received or the current power demand is not less than the idle power. This achieves the adjustment of the power output of the fuel cell system under the idle condition according to the current power demand of the vehicle controller, meets the various power requirements of the vehicle controller, and improves the applicability of the fuel cell system.

[0042] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0044] Figure 1 A framework diagram of a fuel cell system in one embodiment;

[0045] Figure 2 is a schematic flow chart of a power control method for a fuel cell system in one embodiment;

[0046] Figure 3 A schematic flow chart of a power control method for a fuel cell system in another embodiment;

[0047] Figure 4 for Figure 3 Schematic diagram of the variable calibration;

[0048] Figure 5A rendering of a power control method for a fuel cell system in one embodiment;

[0049] Figure 6 is a structural block diagram of a power control device of a fuel cell system in one embodiment;

[0050] Figure 7 FIG. 1 is a diagram showing the internal structure of a power control device of a fuel cell system in one embodiment. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0052] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0053] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0054] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0055] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the objects used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those shown or described.

[0056] The power control method of the fuel cell system provided in the embodiment of the present application can be applied to Figure 1 In the fuel cell system shown. The fuel cell system may include a controller (Fuel-cell Control Unit, FCU), a stack, a single-chip voltage monitor (Cell Voltage Monitor, CVM), an air flow meter, an intercooler, a humidifier, a humidity control valve, an inlet shut-off valve, an outlet shut-off valve, a back pressure valve, a relief valve, a hydrogen inlet valve, a sensor, a proportional valve, a hydrogen pump, a gas-liquid separator, a heated nitrogen exhaust valve, a heated drain valve, a sensor and a high-voltage component, wherein the high-voltage component may include a DC / DC converter, a current distribution unit (Power Distribution Unit, PDU), a positive temperature coefficient thermistor (Positive Temperature Coefficient, PTC), an air compressor (hereinafter referred to as an air compressor), a water pump, etc., and the sensor may include a pressure sensor (P H2 1. P H2 2. P H2 3) Temperature and pressure sensors (Tair1 / Pair1, Tair2 / Pair2), etc. CVM is set at the anode of the fuel cell stack to detect the single-chip voltage of the fuel cell stack. The PDU is equipped with an air compressor controller connected to the air compressor. The FCU communicates with the VCU to obtain the current power demand of the VCU after the fuel cell system enters the idle condition, and controls the power output of the fuel cell stack according to the current power demand.

[0057] The working principle of the above fuel cell system is as follows: after being filtered, the air passes through the air flow meter, air compressor, intercooler, humidifier, humidity control valve, stack inlet shut-off valve, pressure and temperature sensor Tair1 / Pair1, and then enters the cathode of the stack for chemical reaction. After the reaction is completed, it passes through the pressure and temperature sensor Tair2 / Pair2, stack outlet shut-off valve, humidifier, back pressure valve and relief valve and then is discharged; hydrogen passes through the hydrogen inlet valve, pressure sensor P in turn. H2 1. Proportional valve, hydrogen pump, pressure sensor P H2 2 and then enter the anode of the battery stack for chemical reaction. After the reaction is completed, it is detected by the pressure sensor P H2 3. The gas is discharged after the gas-liquid separator, heated nitrogen exhaust valve and heated water drain valve; the power output by the battery stack enters the PDU after DC / DC to provide power for PTC, water pump, air compressor, etc.

[0058] At present, after the fuel cell system enters the idle condition, the power output by the fuel cell system is a fixed value (i.e., the idle power). In this embodiment, when the fuel cell system enters the idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system, the target current output by the stack to the DC converter is controlled, the target speed of the air compressor is reduced, and the target opening of the stack shut-off valve is adjusted. This achieves the adjustment of the power output of the fuel cell system according to the current required power, and can better respond to the power demand of the VCU.

[0059] In one embodiment, Figure 2 As shown, a power control method for a fuel cell system is provided, and the method is applied to Figure 1 Taking the FCU in the example as an example, the method may include the following steps:

[0060] Step 201 , when the fuel cell system enters an idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system, enter a power regulation mode.

[0061] The idle power refers to the preset fixed power of the fuel cell system under idle conditions, and its size can be set differently according to the specific use environment. For example, the idle power can be set to 8KW.

[0062] It should be understood that when the fuel cell system is running under idle conditions, its idle power is fixed. The fuel cell system usually controls the voltage of the stack below 0.85V to prevent the voltage from being at a high potential for a long time, causing carbon corrosion, thereby affecting the life of the stack and the performance of the fuel cell system. At the same time, when the fuel cell system is running under idle conditions, in addition to the power consumption of the energy-consuming components inside the system, it is sometimes necessary to output power to the outside. For the long-term idling requirements of the VCU, the external output power of the fuel cell system is easier to fill the remaining capacity (State-Of-Charge, SOC) of the power battery. When the SOC of the power battery exceeds the SOC upper charge limit, the fuel cell system will shut down. When the SOC of the power battery is lower than the SOC lower charge limit, it will cause the fuel cell system to start idling. The fuel cell system is in two states of idling and shutting down for a long time, which has a great impact on the life of the system. Therefore, it is particularly important to control the power regulation of the fuel cell system under idle conditions.

[0063] When the external output power of the fuel cell system is greater than 0, the power output of the stack is less than the idle power. According to the power consumption information of the whole vehicle, the external output power of the fuel cell system is adjusted for idle speed control (such as the power consumption of the headlights of the whole vehicle is 300w, or the radio and multimedia need to be turned on to consume energy, etc.), and there is no need for the power battery to supplement discharge; when the external output power of the fuel cell system is equal to 0, the power output of the stack is just enough to be consumed by the energy-consuming components of the system, and there is no power output to the outside; when the external output power of the fuel cell system is less than 0, for example, the minimum power that the stack can output is 500w (to ensure that it is not at the minimum power that the high unit of the stack voltage can reach), the power consumption of the energy-consuming components is greater than 500w, and the external output power is less than 0 at this time, and the power battery needs to be discharged to the outside, which also avoids the problem of overcharging the power battery at idle power.

[0064] In the specific implementation, after the fuel cell system responds to the starting demand of the VCU, it is in a normal operating state. In this state, the power output by the fuel cell system is between the idle power and the rated power, and responds according to the power request of the VCU. When the fuel cell system has been successfully started to idle (the state is the normal operating mode, the output power is the idle power, and the corresponding stack current is the variable PwrMng_iStkCurrentTgtIdle_C) or deloaded to idle, and the current required power of the VCU obtained is less than the idle power, it enters the power regulation mode.

[0065] Of course, before entering the power regulation mode, the FCU can also determine the first time that the current demand power is less than the idle power; if the first time is greater than or equal to the first preset time, the step of entering the power regulation mode is executed. For example, the first time is set to 5s, and the power regulation mode is entered only when the current demand power is less than the idle power for 5s or more. By setting the delay in this way, frequent switching of the operating state of the fuel cell system can be avoided, and the stability of power regulation can be improved.

[0066] Step 202, adjusting the target current output by the stack to the DC converter according to the current required power.

[0067] It should be understood that the FCU can use a variety of methods to adjust the target current (the corresponding variable is PwrMng_i_MinPower_C) according to the current required power. In one example, the FCU searches for the current corresponding to the current required power from a preset mapping table, where the preset mapping table is used to characterize the correspondence between the required power and the current output from the battery stack to the DC converter; the target current is set to the current found. The target current can be quickly obtained by looking up the table, which improves the power regulation efficiency.

[0068] Step 203, reducing the target speed of the air compressor.

[0069] An air compressor is a device used to compress gas. Most air compressors are reciprocating piston type, rotating blades or rotating screws. In a fuel cell system, an air compressor is used to provide high-pressure air for the cathode reaction of the fuel cell stack. By adjusting the target speed of the air compressor, the amount of air entering the stack can be controlled.

[0070] Specifically, the FCU can reduce its target speed by calibrating the speed of the air compressor. In one example, the FCU can set the target speed to the minimum speed of the air compressor to minimize the amount of air introduced to the cathode.

[0071] Of course, the FCU can also calibrate the target opening of the back pressure valve and the target opening of the relief valve at the same time, for example, setting the target opening of the back pressure valve to the minimum opening of the back pressure valve; setting the target opening of the relief valve to the first preset value. In a specific implementation, the first preset value can be 100 to ensure that the air pressure can be released.

[0072] In addition, when the fuel cell system further includes a PID controller for adjusting air pressure and air flow, the FCU may also set the PID control parameter of the PID controller to zero to cancel the PID adjustment of air pressure and air flow. The FCU may also control the speed of the hydrogen pump to a fixed value, such as a second preset value, instead of the speed of the hydrogen pump changing with the speed of the air compressor, to achieve the purpose of canceling the hydrogen pressure following the air pressure.

[0073] By setting the target speed of the air compressor to the minimum speed, the target opening of the back pressure valve to the minimum opening, the target opening of the relief valve to a fixed value, canceling the PID adjustment of the air pressure and air flow, and canceling the hydrogen pressure following the air pressure, the amount of air can be reduced and the power output of the fuel cell stack can be reduced.

[0074] Step 204, adjusting the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the fuel cell stack.

[0075] It can be understood that the battery stack is composed of multiple battery cells. The single-chip voltage patroller can collect the voltage of each battery cell (i.e., the single-chip voltage) and send the single-chip voltage to the FCU. The FCU filters out the minimum value of the single-chip voltage and adjusts the target opening of the stack shut-off valve according to the minimum value of the single-chip voltage.

[0076] Specifically, the FCU can compare the minimum value of the single-chip voltage of the fuel cell stack with the preset single-chip voltage lower limit value and the preset single-chip voltage upper limit value respectively; when the minimum value of the single-chip voltage is less than the preset single-chip voltage lower limit value, the target opening of the stack entry cut-off valve is set to the upper limit value of the opening of the stack entry cut-off valve; when the minimum value of the single-chip voltage is greater than the preset single-chip voltage upper limit value, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

[0077] It should be noted that when the air compressor is at the minimum speed, the amount of air introduced into the cathode is still large. At this time, the oxygen content can be controlled by the stack-inlet stop valve. The stack-inlet stop valve controls the air flow rate, oxygen starvation on the cathode side, and reduces the stack voltage. At the same time, the size of the stack-inlet stop valve opening is set according to the minimum value of the single-chip voltage, which not only controls the output power of the stack according to the current power demand of the VCU, but also minimizes the output power of the stack, avoiding power waste.

[0078] Step 205 , when a shutdown command is received or the current required power is not less than the idle power, exit the power regulation mode.

[0079] Since the power demand of VCU is constantly changing, when FCU receives the shutdown command sent by VCU, or the current power demand of VCU received is not less than the idle power, it exits the power adjustment mode. Before exiting the power adjustment mode, FCU needs to enter the idle mode first, switch the state to the normal operation mode, and then shut down or respond to the current power demand of VCU.

[0080] In a specific implementation, before exiting the power regulation mode, the FCU may also determine the second time that the current required power is greater than or equal to the idle power; if the second time is greater than or equal to the second preset time, the step of exiting the power regulation mode is executed. For example, the second time is set to 5s, and the power regulation mode is exited only when the current required power is not less than the idle power for 5s or more. By setting the delay in this way, frequent switching of the operating state of the fuel cell system can be avoided, and the stability of power regulation can be improved.

[0081] This embodiment enters the power regulation mode when the fuel cell system enters the idle condition and the current power demand of the vehicle controller is less than the idle power of the fuel cell system; adjusts the target current of the stack output to the DC converter according to the current power demand; reduces the target speed of the air compressor; adjusts the target opening of the stack inlet shut-off valve according to the minimum value of the single-chip voltage of the stack; and exits the power regulation mode when a shutdown command is received or the current power demand is not less than the idle power. This achieves the adjustment of the power output of the fuel cell system under the idle condition according to the current power demand of the vehicle controller, meets various power requirements of the vehicle controller, and improves the applicability of the fuel cell system.

[0082] Figure 3 FIG. 1 is a flow chart of a power control method for a fuel cell system in another embodiment. Figure 3 As shown, the power control method of the fuel cell system may include the following steps:

[0083] Step 301, when the fuel cell system enters an idle condition and the current power demand of the vehicle controller is less than the idle power of the fuel cell system and continues for a first time, enter a power regulation mode.

[0084] Step 302, setting the target current output by the stack to the DC converter according to the current required power.

[0085] Step 303, canceling the PID adjustment of the air pressure and the air flow, and canceling the hydrogen pressure following the air pressure.

[0086] Step 304, setting the target speed to the minimum speed of the air compressor, setting the target opening of the back pressure valve to the minimum opening of the back pressure valve, and setting the target opening of the relief valve to a first preset value.

[0087] Step 305 , comparing the minimum value of the single-chip voltage of the fuel cell stack with a preset single-chip voltage lower limit value and a preset single-chip voltage upper limit value respectively.

[0088] Step 306 , when the minimum value of the single chip voltage is less than the preset single chip voltage lower limit value, the target opening of the stack entry cut-off valve is set to the upper opening limit value of the stack entry cut-off valve.

[0089] Step 307 , when the minimum value of the single chip voltage is greater than the preset upper limit value of the single chip voltage, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

[0090] Step 308: exit the power regulation mode when a shutdown command is received or the current required power is not less than the idle power and lasts for a second time.

[0091] Figure 4 for Figure 3 Schematic diagram of variable calibration, the variables that need to be calibrated in this embodiment are: the first time and the second time FCSM_ti_MinPowerDb_C, the target current PwrMng_i_MinPower_C, the target opening of the back pressure valve Air_rBpvCrlMin_C, the target speed of the air compressor Air_rCmpMin_C, the target opening of the relief valve Air_r_BypassMinPower_C, the preset single-chip voltage lower limit CVMvE_u_CellVMinPowerMin, the opening upper limit SOV_r_MinPowerMax of the stack cut-off valve, the preset single-chip voltage upper limit CVMvE_u_CellVMinPowerMax, and the opening lower limit SOV_r_MinPowerMin of the stack cut-off valve.

[0092] In an example, the first and second times FCSM_ti_MinPowerDb_C can both be set to 500, the target current PwrMng_i_MinPower_C can be set to 10, the target opening of the relief valve Air_r_BypassMinPower_C can be set to 100, the preset single-chip voltage upper limit CVMvE_u_CellVMinPowerMax can be set to 1450, the preset single-chip voltage lower limit CVMvE_u_CellVMinPowerMin can be set to 1300, the opening upper limit SOV_r_MinPowerMax of the stack entry shut-off valve can be set to 8, and the opening lower limit SOV_r_MinPowerMin of the stack entry shut-off valve can be set to 5.

[0093] In the specific implementation, taking the idle power of 8KW, the first time and the second time are 500 minutes and seconds, the corresponding value of the state machine in the normal operating mode is 17, and the corresponding value of the state machine in the power adjustment mode is 20 as an example, after the fuel cell system is powered on, if the output power is 8KW, the corresponding value of the state machine is 17, the current required power of the VCU is less than 8KW and lasts for 500 minutes and seconds or more, the fuel cell system enters the power adjustment mode, and the corresponding value of its state machine is 20.

[0094] The FCU searches the preset mapping table according to the current required power, sets the target current output by the stack to the DC converter to the current 10 obtained by the search, sets the target opening of the discharge valve Air_r_BypassMinPower_C to 100, sets the target speed of the air compressor Air_rCmpMin_C to the minimum speed, sets the target opening of the back pressure valve Air_rBpvCrlMin_C to the minimum opening, sets the preset upper limit of the single chip voltage CVMvE_u_CellVMinPowerMax to 1450, sets the preset lower limit of the single chip voltage CVMvE_u_CellVMinPowerMin to 1300, sets the upper limit of the opening of the stack entry cut-off valve SOV_r_MinPowerMax to 8, and sets the lower limit of the opening of the stack entry cut-off valve SOV_r_MinPowerMin to 5. If the minimum value of the single chip voltage is less than 1300, the target opening of the stack entry cut-off valve is set to 8; if the minimum value of the single chip voltage is greater than 1450, the target opening of the stack entry cut-off valve is set to 5.

[0095] If the current power demand of the VCU is not less than 8KW and lasts for 500 minutes or more, or the VCU sends a shutdown command and lasts for 500 minutes or more, the corresponding value of the state machine is switched to 17, and the fuel cell system exits the power regulation mode.

[0096] Figure 5FIG. 1 is a diagram showing the effect of a power control method for a fuel cell system in an embodiment. Figure 5 As shown, when the value corresponding to the state machine of the fuel cell system jumps from 17 to 20, that is, after entering the power regulation mode, the minimum value of the single-chip voltage CVMvE_u_CellVoltMin is 1.514, which is greater than the preset single-chip voltage upper limit of 1.450. After setting the target opening SOV_TargetPosition of the stack shut-off valve to 5, the power output of the stack is adjusted from 8KW to about 1.9KW.

[0097] In this embodiment, the above scheme is used to adjust the minimum power of the fuel cell system under idle conditions according to the required power of the VCU, thereby improving the life of the fuel cell system and enhancing the applicability of the fuel cell system.

[0098] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0099] Based on the same inventive concept, the present application also provides a power control device for a fuel cell system, such as Figure 6 As shown, the fuel cell system includes a fuel cell stack, a single-chip voltage patroller, a DC converter, an air compressor and a stack entry shut-off valve. The power control device of the fuel cell system includes: a power regulation start unit 601, which is used to enter the power regulation mode when the fuel cell system enters the idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system; a target current determination unit 602, which is used to adjust the target current output by the fuel cell stack to the DC converter according to the current required power; a target speed determination unit 603, which is used to reduce the target speed of the air compressor; a target opening determination unit 604, which is used to adjust the target opening of the stack entry shut-off valve according to the minimum value of the single-chip voltage of the fuel cell stack; a power regulation closing unit 605, which is used to exit the power regulation mode when a shutdown command is received or the current required power is not less than the idle power.

[0100] In one embodiment, the target opening determination unit 604 is also used to compare the minimum value of the single-chip voltage of the fuel cell stack with the preset single-chip voltage lower limit value and the preset single-chip voltage upper limit value respectively; when the minimum value of the single-chip voltage is less than the preset single-chip voltage lower limit value, the target opening of the stack entry shut-off valve is set to the upper limit value of the opening of the stack entry shut-off valve; when the minimum value of the single-chip voltage is greater than the preset single-chip voltage upper limit value, the target opening of the stack entry shut-off valve is set to the lower limit value of the opening of the stack entry shut-off valve.

[0101] In one embodiment, the target current determination unit 602 is also used to search for the current corresponding to the current required power from a preset mapping table, wherein the preset mapping table is used to characterize the correspondence between the required power and the current output by the battery stack to the DC converter; and the target current is set to the found current.

[0102] In one embodiment, the target speed determination unit 603 is further configured to set the target speed as the minimum speed of the air compressor.

[0103] In one embodiment, the target opening determination unit 604 is further configured to set the target opening of the back pressure valve to the minimum opening of the back pressure valve; and set the target opening of the relief valve to a first preset value.

[0104] In one embodiment, the power control device of the fuel cell system further includes a gas control unit (not shown) for setting the PID control parameter of the PID controller to zero; and controlling the rotation speed of the hydrogen pump to a second preset value.

[0105] In one embodiment, the power control device of the fuel cell system also includes a delay unit (not shown), which is used to determine the first time that the current required power continues to be less than the idle power; when the first time is greater than or equal to the first preset time, execute the step of entering the power regulation mode; and determine the second time that the current required power continues to be greater than or equal to the idle power; when the second time is greater than or equal to the second preset time, execute the step of exiting the power regulation mode.

[0106] Each module in the power control device of the fuel cell system can be implemented in whole or in part by software, hardware or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0107] Based on the same inventive concept, an embodiment of the present application also provides a power control device for a fuel cell system. Figure 7 FIG. 1 is an internal structure diagram of a power control device of a fuel cell system in one embodiment. Figure 7As shown, the power control device of the fuel cell system includes one or more memories 704, one or more processors 702, and at least one computer program (program code) stored in the memory 704 and executable on the processor 702. When the processor 702 executes the computer program, the power control method of the fuel cell system as described above is implemented.

[0108] Among them, Figure 7 In the embodiment of the present invention, a bus architecture (represented by bus 700) is shown, which may include any number of interconnected buses and bridges, and bus 700 links various circuits including one or more processors represented by processor 702 and memory represented by memory 704. Bus 700 may also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. Bus interface 705 provides an interface between bus 700 and receiver 701 and transmitter 703. Receiver 701 and transmitter 703 may be the same element, namely a transceiver, providing a unit for communicating with various other devices over a transmission medium. Processor 702 is responsible for managing bus 700 and general processing, while memory 704 may be used to store data used by processor 702 when performing operations.

[0109] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the scheme of the present application, and does not constitute a limitation on the power control device of the fuel cell system to which the scheme of the present application is applied. The power control device of a specific fuel cell system may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0110] Based on the same inventive concept, the embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0111] When the fuel cell system enters the idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system, the power regulation mode is entered;

[0112] Adjust the target current output by the stack to the DC converter according to the current power demand;

[0113] Reduce the target speed of the air compressor;

[0114] The target opening of the stack entry cut-off valve is adjusted according to the minimum value of the single-chip voltage of the stack;

[0115] When a shutdown command is received or the current required power is not less than the idle power, the power adjustment mode is exited.

[0116] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: the minimum value of the single-chip voltage of the fuel cell stack is compared with the preset single-chip voltage lower limit value and the preset single-chip voltage upper limit value respectively; when the minimum value of the single-chip voltage is less than the preset single-chip voltage lower limit value, the target opening of the stack entry cut-off valve is set to the upper limit value of the opening of the stack entry cut-off valve; when the minimum value of the single-chip voltage is greater than the preset single-chip voltage upper limit value, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

[0117] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: searching for the current corresponding to the current required power from a preset mapping table, wherein the preset mapping table is used to characterize the correspondence between the required power and the current output by the battery stack to the DC converter; setting the target current to the found current.

[0118] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented: setting the target rotation speed as the minimum rotation speed of the air compressor.

[0119] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: setting the target opening of the back pressure valve to the minimum opening of the back pressure valve; setting the target opening of the relief valve to a first preset value.

[0120] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: setting the PID control parameter of the PID controller to zero; and controlling the rotation speed of the hydrogen pump to a second preset value.

[0121] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: determining the first time that the current required power is less than the idle power; and executing the step of entering the power regulation mode when the first time is greater than or equal to the first preset time.

[0122] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: determining that the current required power is greater than or equal to the second time that the idle power lasts; and when the second time is greater than or equal to the second preset time, executing the step of exiting the power regulation mode.

[0123] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of the present application and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. In addition, each functional unit may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit.

[0124] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0125] The units described as separate components may or may not be physically separated, and the components of the control device may or may not be physical units, that is, they may be located in one place or distributed in multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0126] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0127] The above description is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the claims of the present application.

Claims

1. A power control method for a fuel cell system, characterized in that: The fuel cell system includes a fuel cell stack, a single-chip voltage patroller, a DC converter, an air compressor, and a stack entry shutoff valve. The power control method of the fuel cell system includes: When the fuel cell system enters an idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system, entering a power regulation mode; Adjusting the target current output by the stack to the DC converter according to the current required power; reducing a target speed of the air compressor; adjusting the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack; When a shutdown command is received or the current required power is not less than the idle power, exiting the power adjustment mode; Wherein, adjusting the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack includes: Comparing the minimum value of the single-chip voltage of the battery stack with a preset single-chip voltage lower limit value and a preset single-chip voltage upper limit value respectively; When the minimum value of the single chip voltage is less than the preset single chip voltage lower limit value, setting the target opening of the stack entry cut-off valve to the upper opening limit value of the stack entry cut-off valve; When the minimum value of the single chip voltage is greater than the preset upper limit value of the single chip voltage, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

2. The power control method of the fuel cell system according to claim 1, characterized in that: The step of adjusting the target current output by the stack to the DC converter according to the current required power includes: Searching for the current corresponding to the current required power from a preset mapping table, wherein the preset mapping table is used to characterize the corresponding relationship between the required power and the current output from the battery stack to the DC converter; The target current is set to the found current.

3. The power control method of the fuel cell system according to claim 1, characterized in that: The step of reducing the target rotation speed of the air compressor comprises: The target rotation speed is set to the minimum rotation speed of the air compressor.

4. The power control method of the fuel cell system according to claim 3, characterized in that: The fuel cell system further includes a back pressure valve and a leakage valve, and the power control method further includes: Setting the target opening of the back-pressure valve to the minimum opening of the back-pressure valve; The target opening of the relief valve is set to a first preset value.

5. The power control method of the fuel cell system according to claim 1, characterized in that: The fuel cell system further includes a hydrogen pump and a PID controller for adjusting air pressure and air flow, and the power control method further includes: Setting the PID control parameters of the PID controller to zero; The rotation speed of the hydrogen pump is controlled to be a second preset value.

6. The power control method of a fuel cell system according to any one of claims 1 to 5, characterized in that: Before entering the power regulation mode, the power control method further includes: Determine a first time that the current required power is less than the idle power; When the first time is greater than or equal to the first preset time, executing the step of entering the power adjustment mode; Accordingly, before exiting the power regulation mode, the power control method further includes: Determine a second time period during which the current required power is greater than or equal to the idle power; When the second time is greater than or equal to a second preset time, the step of exiting the power adjustment mode is performed.

7. A power control device for a fuel cell system, characterized in that: The fuel cell system includes a fuel cell stack, a single-chip voltage patroller, a DC converter, an air compressor and a stack entry shutoff valve. The power control device of the fuel cell system includes: A power regulation start unit, used to enter a power regulation mode when the fuel cell system enters an idle condition and the current required power of the vehicle controller is less than the idle power of the fuel cell system; a target current determination unit, configured to adjust a target current output by the battery stack to the DC converter according to the current required power; a target speed determination unit, configured to reduce a target speed of the air compressor; a target opening determination unit, configured to adjust the target opening of the stack entry cut-off valve according to the minimum value of the single-chip voltage of the stack; A power regulation shutdown unit, configured to exit the power regulation mode when a shutdown command is received or the current required power is not less than the idle power; Wherein, the target opening determination unit is further used to compare the minimum value of the single-chip voltage of the stack with a preset single-chip voltage lower limit value and a preset single-chip voltage upper limit value respectively; When the minimum value of the single chip voltage is less than the preset single chip voltage lower limit value, setting the target opening of the stack entry cut-off valve to the upper opening limit value of the stack entry cut-off valve; When the minimum value of the single chip voltage is greater than the preset upper limit value of the single chip voltage, the target opening of the stack entry cut-off valve is set to the lower limit value of the opening of the stack entry cut-off valve.

8. A power control device for a fuel cell system, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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