CN117681728A - Method and device for overcharge protection of power battery, vehicle and storage medium - Google Patents

Abstract

The application provides a method, a device, a vehicle and a storage medium for overcharge protection of a power battery, wherein the method comprises the following steps: obtaining a single voltage value of a vehicle power battery; judging whether the single voltage of the power battery is in an overvoltage state or not; in the event that it is determined that the cell voltage of the power cell is in an overvoltage condition, the fuel cell of the vehicle is disabled from starting. When the single voltage of the power battery is in an overvoltage state, the method can inhibit the starting of the fuel battery, so that the fuel battery does not work and does not output power under the condition that the single voltage of the power battery is in the overvoltage state, the condition that the power battery is overcharged due to the fact that the power battery is charged by the fuel battery is avoided, the frequency of emergency shutdown of the fuel battery under the condition can be reduced due to the fact that the starting of the fuel battery is inhibited, and the service life of the fuel battery is prolonged.

Description

Method and device for overcharge protection of power battery, vehicle and storage medium

Technical Field

The present application relates to the field of vehicles, and more particularly, to a method, apparatus, vehicle, and storage medium for power battery overcharge protection in the field of vehicles.

Background

The power battery is formed by connecting a plurality of battery modules in series, each battery module has different voltages, and the voltage of each battery module can be called as the single voltage of the power battery. When any group of battery modules is in an overvoltage state, the power battery of the vehicle is in a state of single voltage overvoltage.

In the prior art, when the power battery of the vehicle is in a state of overvoltage of single voltage, the voltage protection of the power battery is activated, and the new energy power domain controller (Powertrain Domain Control Unit, PDCU) can limit the generated torque of the front driving motor controller (Front Drive Motor Control Unit, FMCU) and the rear driving motor controller (Rear Drive Motor Control Unit, RMCU) so as to prevent the power battery from being overcharged. However, limiting the motor generated torque alone cannot completely prevent overcharging of the power battery.

Disclosure of Invention

The application provides a method, a device, a vehicle and a storage medium for protecting the overcharge of a power battery, wherein the method can inhibit the starting of the fuel battery and avoid the condition that the power output by the fuel battery is charged back to the power battery to cause the overcharge of the power battery.

In a first aspect, a method for overcharge protection of a power cell is provided, the method comprising: obtaining a single voltage value of a vehicle power battery; judging whether the single voltage of the power battery is in an overvoltage state or not; in the event that it is determined that the cell voltage of the power cell is in an overvoltage condition, the fuel cell of the vehicle is disabled from starting.

In the technical scheme, when the single voltage of the power battery is in an overvoltage state, the starting of the fuel battery is forbidden, so that the fuel battery does not work and does not output power under the condition that the single voltage of the power battery is in the overvoltage state, the condition that the power battery is overcharged due to the fact that the power battery is charged by the fuel battery is avoided, the frequency of emergency shutdown of the fuel battery under the scene can be reduced due to the fact that the starting of the fuel battery is forbidden, and the service life of the fuel battery is prolonged.

With reference to the first aspect, in some possible implementations, disabling the fuel cell of the vehicle includes: acquiring the current state of the fuel cell; controlling the fuel cell to stop and prohibiting the fuel cell from starting under the condition that the current state of the fuel cell is a starting state; and when the fuel cell is not in a starting state, prohibiting the fuel cell from starting.

With reference to the first aspect and the foregoing implementation manner, in some possible implementation manners, when the fuel cell is in a start-up state, controlling the fuel cell to stop and prohibit the fuel cell from starting includes: acquiring the speed of the vehicle under the condition that the fuel cell is in a starting state; when the speed of the vehicle is smaller than the preset speed, the emergency stop of the fuel cell is controlled, and the starting of the fuel cell is forbidden.

In the technical scheme, the vehicle speed is less than the preset vehicle speed without power, the power can be output in the starting state of the fuel cell, the power output by the fuel cell can charge the power cell, so that the power cell is overcharged, the emergency stop of the fuel cell is controlled, the power output by the fuel cell is cut off, the power cell of the vehicle can be protected, the overcharged power cell is prevented, the frequency of the emergency stop of the fuel cell can be reduced when the fuel cell is forbidden to be started, and the fuel cell of the vehicle is protected.

With reference to the first aspect and the foregoing implementation manner, in some possible implementation manners, the method further includes: when the speed of the vehicle is greater than a preset speed, acquiring the output power of the fuel cell and the whole vehicle request power of the vehicle; when the output power is determined to be greater than the request power of the whole vehicle, controlling the emergency stop of the fuel cell and prohibiting the fuel cell from starting; and when the output power is determined to be less than or equal to the request power of the whole vehicle, controlling the fuel cell to stop normally, and prohibiting the fuel cell from starting.

With reference to the first aspect and the foregoing implementation manner, in some possible implementation manners, in a process of controlling a normal shutdown of a fuel cell, detecting whether a real-time output power of the fuel cell is greater than a real-time request power of a whole vehicle of the vehicle; and when the real-time output power is determined to be larger than the real-time request power of the whole vehicle, controlling the emergency stop of the fuel cell and prohibiting the starting of the fuel cell.

In the technical scheme, the real-time output power of the fuel cell and the real-time request power of the whole vehicle of the vehicle are monitored in the normal shutdown process of the fuel cell, and the emergency shutdown of the fuel cell is controlled when the real-time output power is larger than the real-time request power of the whole vehicle, so that the overcharge of the power cell can be more comprehensively prevented, and the power cell of the vehicle is protected.

With reference to the first aspect and the foregoing implementation manner, in some possible implementation manners, when determining that the output power is less than or equal to the request power of the whole vehicle, predicting whether an emergency load shedding working condition exists in the vehicle after a first preset duration; and when the emergency load reduction working condition of the vehicle is determined, controlling the emergency stop of the fuel cell, and prohibiting the fuel cell from starting.

According to the technical scheme, when the output power is smaller than or equal to the request power of the whole vehicle, whether the vehicle has an emergency load reduction working condition after a preset time period is predicted, and the fuel cell is controlled to stop in advance when the vehicle is predicted to have the emergency load reduction working condition, so that the power cell of the vehicle can be further protected, and the power cell is prevented from being overcharged.

With reference to the first aspect and the foregoing implementation manner, in some possible implementation manners, determining whether a cell voltage of the power battery is in an overvoltage state includes: judging whether the duration that the voltage value of the single body is larger than a preset threshold exceeds a second preset duration; and when the duration that the single voltage value is larger than the preset threshold value exceeds the second preset duration, determining that the single voltage of the power battery is in an overvoltage state.

In the technical scheme, the single voltage of the power battery is compared with the preset threshold value, and the single voltage of the power battery is determined to be in an overvoltage state after the single voltage of the power battery is larger than the preset threshold value and the time length of the single voltage larger than the preset threshold value exceeds the second preset time length, so that the situation that the measured voltage value is larger than the preset threshold value at a certain moment but the voltage value is rapidly reduced to be lower than the preset threshold value can be avoided, and the current state of the power battery can be accurately judged.

In summary, when the single voltage of the power battery is in an overvoltage state, the starting of the fuel battery is forbidden, so that the fuel battery does not work and does not output power under the condition that the single voltage of the power battery is in the overvoltage state, the condition that the power battery is overcharged due to the fact that the fuel battery charges the power battery is avoided, the frequency of emergency shutdown of the fuel battery under the scene can be reduced due to the fact that the starting of the fuel battery is forbidden, and the service life of the fuel battery is prolonged. The vehicle speed is smaller than the preset vehicle speed, power is not required, the power is output in the starting state of the fuel cell, the power output by the fuel cell charges the power cell, so that the power cell is overcharged, the emergency stop of the fuel cell is controlled, the power output by the fuel cell is cut off, the power cell of the vehicle can be protected, the overcharged power cell is prevented, the frequency of the emergency stop of the fuel cell can be reduced when the fuel cell is forbidden to start, and the fuel cell of the vehicle is protected. The real-time output power of the fuel cell and the real-time request power of the whole vehicle of the vehicle are monitored in the normal shutdown process of the fuel cell, and the emergency shutdown of the fuel cell is controlled when the real-time output power is larger than the real-time request power of the whole vehicle, so that the overcharge of the power cell can be more comprehensively prevented, and the power cell of the vehicle is protected. When the output power is smaller than or equal to the request power of the whole vehicle, whether the vehicle has an emergency load reduction working condition or not is predicted, and the fuel cell is controlled to stop in advance when the vehicle has the emergency load reduction working condition, so that the power cell of the vehicle can be further protected, and the power cell is prevented from being overcharged. By acquiring the single voltage of the power battery and comparing the single voltage with the preset threshold, and determining that the single voltage of the power battery is in an overvoltage state after the single voltage of the power battery is larger than the preset threshold and the single voltage exceeds the second preset time, the situation that the measured voltage value is larger than the preset threshold at a certain moment but the voltage value is rapidly reduced to be lower than the preset threshold can be avoided, and the current state of the power battery can be accurately judged.

In a second aspect, there is provided an apparatus for overcharge protection of a power cell, the apparatus comprising: the acquisition module is used for acquiring the single voltage value of the vehicle power battery; the judging module is used for judging whether the single voltage of the power battery is in an overvoltage state or not; and the control module is used for prohibiting the starting of the fuel cell of the vehicle under the condition that the single voltage of the power cell is in an overvoltage state.

With reference to the second aspect, in some possible implementations, the control module is specifically configured to: acquiring the current state of the fuel cell; controlling the fuel cell to stop and prohibiting the fuel cell from starting under the condition that the current state of the fuel cell is a starting state; and when the fuel cell is not in a starting state, prohibiting the fuel cell from starting.

With reference to the implementation manner of the second aspect, in some possible implementation manners, the control module is specifically configured to: acquiring the speed of the vehicle under the condition that the fuel cell is in a starting state; when the speed of the vehicle is smaller than the preset speed, the emergency stop of the fuel cell is controlled, and the starting of the fuel cell is forbidden.

With reference to the second aspect and the foregoing implementation manner, in some possible implementation manners, the obtaining module is further configured to obtain, when a vehicle speed of the vehicle is greater than a preset vehicle speed, an output power of the fuel cell and a vehicle whole request power of the vehicle; the control module is also used for controlling the emergency stop of the fuel cell and prohibiting the start of the fuel cell when the output power is determined to be larger than the request power of the whole vehicle; and when the output power is determined to be less than or equal to the request power of the whole vehicle, controlling the fuel cell to stop normally, and prohibiting the fuel cell from starting.

With reference to the second aspect and the foregoing implementation manner, in some possible implementation manners, the apparatus further includes: the detection module is used for detecting whether the real-time output power of the fuel cell is larger than the real-time request power of the whole vehicle of the vehicle in the process of controlling the normal shutdown of the fuel cell; the control module is also used for controlling the emergency stop of the fuel cell and prohibiting the start-up of the fuel cell when the real-time output power is determined to be larger than the real-time request power of the whole vehicle.

With reference to the second aspect and the foregoing implementation manner, in some possible implementation manners, the apparatus further includes: the prediction module is used for predicting whether an emergency load reduction working condition exists after a first preset duration of the vehicle when the output power is determined to be smaller than or equal to the request power of the whole vehicle; the control module is also used for controlling the emergency stop of the fuel cell and prohibiting the fuel cell from starting when the emergency load-reducing working condition of the vehicle is determined.

With reference to the second aspect and the foregoing implementation manner, in some possible implementation manners, the determining module is specifically configured to: judging whether the duration that the voltage value of the single body is larger than a preset threshold exceeds a second preset duration; and when the duration that the single voltage value is larger than the preset threshold value exceeds the second preset duration, determining that the single voltage of the power battery is in an overvoltage state.

In a third aspect, a vehicle is provided that includes a memory and a processor. The memory is for storing executable program code and the processor is for calling and running the executable program code from the memory such that the vehicle performs the method of the first aspect or any of the possible implementations of the first aspect.

In a fourth aspect, there is provided a computer program product comprising: computer program code which, when run on a computer, causes the computer to perform the method of the first aspect or any one of the possible implementations of the first aspect.

In a fifth aspect, a computer readable storage medium is provided, the computer readable storage medium storing computer program code which, when run on a computer, causes the computer to perform the method of the first aspect or any one of the possible implementations of the first aspect.

Drawings

Fig. 1 is a schematic system diagram of an implementation of an embodiment provided in the present application.

FIG. 2 is a schematic flow chart of a method for overcharge protection of a power cell provided in an embodiment of the present application;

Fig. 3 is a schematic structural diagram of an apparatus for overcharge protection of a power battery according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Detailed Description

The technical solutions in the present application will be clearly and thoroughly described below with reference to the accompanying drawings. Wherein, in the description of the embodiments of the present application, "/" means or is meant unless otherwise indicated, for example, a/B may represent a or B: the text "and/or" is merely an association relation describing the associated object, and indicates that three relations may exist, for example, a and/or B may indicate: the three cases where a exists alone, a and B exist together, and B exists alone, and in addition, in the description of the embodiments of the present application, "plural" means two or more than two.

The terms "first," "second," and the like, are used below for descriptive purposes only and are not to be construed as implying or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature.

In the prior art, when a power battery of a vehicle is in a state of single voltage overvoltage, the voltage protection of the power battery is activated, and a PDCU can limit the power generation torque of a front drive motor and a rear drive motor so as to prevent the power battery from being overcharged.

However, limiting the motor generated torque alone cannot completely prevent overcharging of the power battery. For example, when the vehicle has an emergency load-reducing working condition, the vehicle is suddenly switched from a state requiring power to a state not requiring power, the vehicle can only consume a small amount of power generated by the fuel cell, even the vehicle does not need power after the vehicle has the emergency load-reducing working condition, and at the moment, the power output by the fuel cell is charged back to the power cell, so that the power cell is overcharged.

The application provides a method for protecting the overcharge of a power battery, which can inhibit the starting of the fuel battery when the voltage of a single power battery is in an overvoltage state, so as to avoid the condition that the power output by the fuel battery is recharged to cause the overcharge of the power battery when an emergency load-reducing working condition occurs to a vehicle.

Fig. 1 is a schematic system diagram of an implementation of an embodiment provided in the present application.

It should be appreciated that a method of power cell overcharge protection provided herein may be applied to the vehicle 100 of fig. 1.

Illustratively, as shown in FIG. 1, the vehicle 100 includes: a fuel cell 10, a power cell 20, and a motor 30.

The fuel cell 10 is connected to the motor 30 for outputting power to the motor 30. Specifically, when the fuel cell 10 is started, the vehicle may transmit hydrogen and oxygen to the fuel cell 10, cause the fuel cell 10 to chemically react the hydrogen and the oxygen to generate electric energy, and output the generated electric energy to the motor 30.

The power battery 20 is connected to the motor 30 for outputting power to the motor 30. The power battery 20 is a rechargeable battery, and may be a lithium ion battery, for storing energy by charging, and outputting electric energy to the motor 30 during the running of the vehicle.

In some embodiments, it may be that the fuel cell 10 and the power cell 20 together output electrical energy to the motor 30.

The motor 30 is configured to receive electric energy transmitted from the fuel cell 10 and/or the power battery 20, convert the electric energy into kinetic energy, and output torque to drive the vehicle.

In some embodiments, when the vehicle is a four-wheel drive vehicle, the motor 30 may include a front-drive motor for driving the front wheels of the vehicle and a rear-drive motor for driving the rear wheels of the vehicle. The motor 30 can reversely generate electricity under certain conditions to charge the power battery 20.

Optionally, the fuel cell 10 is further connected to a power cell 20, and the power cell 20 supplies power to the fuel cell 10 to start the fuel cell 10, and the fuel cell 10 can also deliver power to the power cell 20 under certain conditions to realize charging of the power cell 20.

Fig. 2 is a schematic flow chart of a method for overcharge protection of a power cell provided in an embodiment of the present application. The method is applied to the vehicle 100 shown in fig. 1.

Illustratively, as shown in FIG. 2, the method 200 includes:

step 201, obtaining a single voltage value of a vehicle power battery;

the power battery of the vehicle can be formed by connecting a plurality of battery modules in series, each battery module corresponds to one voltage, and the voltages corresponding to the battery modules can be the same or different. The corresponding voltage of each battery module is the single voltage of the power battery.

Each battery module can be formed by connecting a plurality of lithium batteries in series or in parallel.

Specifically, a battery management system (Battery Management System, BMS) is arranged in the vehicle, so that the single voltage value of the power battery of the vehicle can be obtained in real time.

Step 202, judging whether the single voltage of the power battery is in an overvoltage state;

the power battery of the vehicle can be charged for energy storage, the stored electric energy output power is consumed in the running process of the vehicle, and then the electric energy consumed by the power battery is supplemented by charging through the charging pile when the electric quantity of the power battery is too small. The power cell may fail due to poor equalization function or failure of the local monitoring unit (Local Monitoring Unit, LMU) or due to low cell capacity, faster voltage rise during charging, etc., resulting in an overvoltage condition of the cell voltage of the power cell.

Specifically, the BMS system in the vehicle may monitor whether the cell voltage of the power battery of the vehicle is in an overvoltage state based on the cell voltage value of the power battery of the vehicle acquired in real time.

In one possible implementation, determining whether the cell voltage of the power battery is in an overvoltage condition includes: judging whether the duration that the voltage value of the single body is larger than a preset threshold exceeds a second preset duration; and when the duration that the single voltage value is larger than the preset threshold value exceeds the second preset duration, determining that the single voltage of the power battery is in an overvoltage state.

According to the above embodiment, the power battery is formed by connecting a plurality of battery modules in series, and each battery module corresponds to one voltage, so that the power battery corresponds to a plurality of single voltages. The voltage values of all the battery modules forming the power battery can be obtained, and the single voltage value of the power battery is obtained.

It should be understood that the battery is operating normally with a range of voltages corresponding to the maximum voltage that the battery is in full state. Each battery module that power battery includes also has certain voltage range when normally working. The parameters corresponding to the battery modules of the power battery of the same vehicle may be the same, i.e., the power battery modules have the same maximum voltage. The maximum voltage corresponding to each battery module may be used as a preset threshold, assuming that the preset threshold is 4.6V.

And comparing the obtained voltage values corresponding to the battery modules of the power battery with a preset threshold value, and determining that the single voltage of the power battery is in an overvoltage state as long as one of the voltage values is larger than the preset threshold value and the duration time of the voltage value is larger than the preset threshold value exceeds the preset duration time.

The voltage of each battery module may be due to other reasons, such that the voltage value measured by the battery management system (Battery Management System, BMS) at a certain moment is greater than a preset threshold, but the voltage value at the next moment is rapidly reduced below the preset threshold, and at this moment, it cannot be determined that the cell voltage of the power battery is in an overvoltage state. The second preset time period may be set for excluding the measured voltage value of the battery module from being accidental. The second preset duration may be set according to an actual situation, and in this embodiment of the present application, it is assumed that the second preset duration is 3s.

Illustratively, assume that the power cell includes four sets of battery modules: a battery module, B battery module, C battery module and D battery module. Suppose BMS real-time supervision power battery's monomer voltage, the voltage value that each battery module corresponds at a moment of acquisition specifically is: a battery module 3.5V, B battery module 3.6V, C battery module 3.7V and D battery module 3.7V. And judging the obtained voltage value of each battery module and a preset threshold value of 3.6V to obtain the voltage values of the C battery module and the D battery module which are larger than the preset threshold value. Assuming that the voltage value of the battery module C is monitored by the BMS to be 3.7V for 2s, the duration that the voltage value of the battery module C is larger than the preset threshold value is smaller than the second preset duration for 3s, and at the moment, the condition that the voltage value of the battery module C is temporarily too high due to other reasons can be determined, and the single voltage of the power battery cannot be determined to belong to an overvoltage state. Assuming that the voltage value of the battery module D is 3.7V for 4s, the voltage value of the battery module D can be obtained to be longer than the second preset duration 3s when the voltage value of the battery module D is larger than the preset threshold value, and the battery module D can be determined to be in an overvoltage state at the moment, namely the voltage of the battery module D can be determined to be in an overvoltage state.

In the method, the single voltage of the power battery is compared with the preset threshold value, and the single voltage of the power battery is determined to be in an overvoltage state after the single voltage of the power battery is larger than the preset threshold value and the time that the single voltage is larger than the preset threshold value exceeds the second preset time, so that the situation that the measured voltage value is larger than the preset threshold value at a certain moment but the voltage value is rapidly reduced to be lower than the preset threshold value can be avoided, and the current state of the power battery can be accurately judged.

In step 203, in the case where it is determined that the cell voltage of the power cell is in an overvoltage state, the fuel cell of the vehicle is prohibited from being started.

In case the cell voltage of the power battery is in an overvoltage condition, charging of the power battery is avoided. The vehicle shown in fig. 1 further includes a fuel cell that outputs power during traveling of the vehicle and charges the power cell under certain conditions. At the moment, the fuel cell is required to be prohibited from starting under the overvoltage state of the single voltage of the power cell, and the fuel cell is prohibited from working and outputting no power under the condition that the single voltage of the power cell is in the overvoltage state, so that the power cell can be prevented from being charged by the fuel cell, and the power cell is prevented from being overcharged.

In the method, when the single voltage of the power battery is in an overvoltage state, the starting of the fuel battery is forbidden, so that the fuel battery does not work and does not output power under the condition that the single voltage of the power battery is in the overvoltage state, the condition that the power battery is overcharged due to the fact that the power battery is charged by the fuel battery is avoided, the frequency of emergency shutdown of the fuel battery under the scene can be reduced due to the fact that the starting of the fuel battery is forbidden, and the service life of the fuel battery is prolonged.

In one possible implementation, disabling fuel cell activation of a vehicle includes: acquiring the current state of the fuel cell; controlling the fuel cell to stop and prohibiting the fuel cell from starting under the condition that the current state of the fuel cell is a starting state; and when the fuel cell is not in a starting state, prohibiting the fuel cell from starting.

The current state of the fuel cell of the vehicle may include a start state and an un-start state, and the state of the fuel cell may be user-controlled or may be controlled by a controller of the vehicle according to the current driving situation.

For example, the user may select a driving mode before driving, assuming that the user selects a pure power battery running, at which time the fuel cell of the vehicle is in a shut-off state. Or, the power battery does not meet the driving requirement of the user during the running process of the vehicle, and the controller of the vehicle can control the fuel battery to start, i.e. the fuel battery is in a starting state.

The current state of the fuel cell may be determined based on whether the fuel cell is currently outputting power. When the fuel cell is currently outputting power, it may be determined that the fuel cell is in a started state, and when the fuel cell is not currently outputting power, it may be determined that the fuel cell is in an un-started state.

The fuel cell has an optimum efficiency point, and when the current state of the fuel cell is a start-up state, the fuel cell is generally operated at the optimum efficiency point, and the output power of the fuel cell is 10.15kw when the fuel cell is operated at the optimum efficiency point. At this time, the fuel cell needs to be controlled to stop so that the fuel cell does not output power, and then the fuel cell is prohibited from starting.

The fuel cell of the vehicle may be a hydrogen fuel cell, and a hydrogen system is provided in the vehicle, and hydrogen gas that participates in a chemical reaction may be supplied to the fuel cell when the fuel cell is in a start-up state. The hydrogen and oxygen are subjected to proton exchange, and electrochemical energy stored in oxyhydrogen fuel is converted into electric energy to be output.

The operation of controlling the shutdown of the fuel cell may specifically be: the hydrogen system is controlled to stop delivering hydrogen to the fuel cell for chemical reaction. Fuel cell start-up may be inhibited after controlling the fuel cell to stop.

In some embodiments, fuel cell start-up may be directly inhibited while the fuel cell is in an unopened state.

In one possible implementation, controlling the fuel cell to stop and inhibit the fuel cell from starting when the fuel cell is in a start-up state includes: acquiring the speed of the vehicle under the condition that the fuel cell is in a starting state; when the speed of the vehicle is smaller than the preset speed, the emergency stop of the fuel cell is controlled, and the starting of the fuel cell is forbidden.

As in the previous embodiment, the fuel cell is typically operated at the optimum efficiency point with an output of 10.15kw in the start-up state. At this time, the vehicle speed of the vehicle can be acquired first, and whether the vehicle needs power currently or not is judged according to the acquired vehicle speed.

The preset vehicle speed may be a minimum vehicle speed at which the vehicle needs power to drive the wheels, and when the vehicle speed is less than the preset vehicle speed, it may be determined that the current vehicle is in a stationary or to-be-stopped state, it may be determined that the vehicle does not need power at present, and the fuel cell is in a started state and outputs 10.15kw of power, at which time the fuel cell needs to be controlled to stop in an emergency. Otherwise, the power output by the fuel cell would charge the power cell, resulting in overcharging the power cell.

It should be understood that when the fuel cell is in an operating state, the output of power is achieved by outputting current and Voltage to a High Voltage bus of the vehicle with a High Voltage DC-to-DC converter (HVDCDC) converter inside the fuel cell. The operation of controlling the emergency stop of the fuel cell may specifically be: and controlling the hydrogen system to stop delivering hydrogen to the fuel cell for chemical reaction, and switching off the HVDCDC converter in the fuel cell to stop outputting current and voltage to the high-voltage bus. The fuel cell is controlled to be started up after the emergency stop.

In some embodiments, the vehicle may require a certain duration for response, for example, the longest response duration is 8ms, and the HVDCDC converter may be controlled to be disconnected within 8ms to implement emergency shutdown of the fuel cell.

In the method, the power is not needed when the vehicle speed is smaller than the preset vehicle speed, the power is output in the starting state of the fuel cell, the power output by the fuel cell charges the power cell, so that the power cell is overcharged, the emergency stop of the fuel cell is controlled at the moment, the power output by the fuel cell is cut off, the power cell of the vehicle can be protected, the overcharging of the power cell is prevented, the frequency of the emergency stop of the fuel cell can be reduced when the fuel cell is forbidden to be started, and the fuel cell of the vehicle is protected.

In a possible implementation manner, the method further includes: when the speed of the vehicle is greater than a preset speed, acquiring the output power of the fuel cell and the whole vehicle request power of the vehicle; when the output power is determined to be greater than the request power of the whole vehicle, controlling the emergency stop of the fuel cell and prohibiting the fuel cell from starting; and when the output power is determined to be less than or equal to the request power of the whole vehicle, controlling the fuel cell to stop normally, and prohibiting the fuel cell from starting.

When the speed of the vehicle is greater than the preset speed, the current power required by the vehicle to drive the wheels is indicated, and the output power of the fuel cell and the whole vehicle request power of the vehicle can be obtained at the moment, and the size relation between the output power and the whole vehicle request power can be judged. When the output power of the fuel cell is larger than the whole vehicle request power of the vehicle, part of the power output by the fuel cell is consumed by the vehicle, and the remaining output power at the current moment can charge the power cell, so that the power cell is overcharged, and at the moment, the emergency stop of the fuel cell needs to be controlled, and the power output by the fuel cell is cut off.

By way of example, assuming that the current fuel cell is operating at the optimum efficiency point, the output power of the fuel cell is obtained to be 10.15kw. The request power of the whole vehicle of the vehicle can be determined according to the accelerator opening of the vehicle. Assuming that the request power of the whole vehicle is 5kw, and 5kw is smaller than 10.15kw, according to the accelerator opening of the vehicle, the emergency stop of the fuel cell needs to be controlled at this time, and the power output by the fuel cell is cut off. The process of controlling the emergency shutdown of the fuel cell is specifically described in the above-mentioned real-time manner, and will not be described in detail herein.

When the output power of the fuel cell is larger than the whole vehicle request power of the vehicle, all the power output by the fuel cell is consumed by the vehicle, and excessive power does not exist at the current moment to charge the power cell so as to cause the overcharge of the power cell, so that the fuel cell can be controlled to stop normally. The operation of controlling the normal shutdown of the fuel cell may be: the hydrogen system is controlled to stop delivering hydrogen to the fuel cell for chemical reaction.

In a possible implementation manner, the method further includes: in the process of controlling the normal shutdown of the fuel cell, detecting whether the real-time output power of the fuel cell is larger than the real-time request power of the whole vehicle of the vehicle; and when the real-time output power is determined to be larger than the real-time request power of the whole vehicle, controlling the emergency stop of the fuel cell and prohibiting the starting of the fuel cell.

It should be understood that when the fuel cell is controlled to stop normally, unreacted hydrogen still exists in the fuel cell after the hydrogen system stops delivering hydrogen to the fuel cell, and at this time, the fuel cell still performs chemical reaction to output power, and at this time, the output power is smaller and smaller until the hydrogen is reacted. I.e. the fuel cell will still output power for a certain period of time after the fuel cell is normally shut down.

In the normal shutdown process of the fuel cell, the vehicle has the condition that the whole vehicle request power suddenly drops to be smaller than the output power of the fuel cell, for example, after the hydrogen system is controlled to stop delivering hydrogen to the fuel cell, a user wants to control the vehicle to stop and step on the brake of the vehicle to reduce the vehicle speed to be close to zero, and at the moment, the whole vehicle request power of the vehicle is close to zero. The vehicle can monitor the real-time output power of the fuel cell and the real-time request power of the whole vehicle after the hydrogen system is controlled to stop delivering hydrogen to the fuel cell, judge the magnitude relation between the real-time output power and the real-time request power of the whole vehicle, and control the fuel cell to stop in an emergency when the real-time output power is larger than the real-time request power of the whole vehicle. The process of emergency shutdown is as in the above embodiments and will not be described in detail here.

In the method, the real-time output power of the fuel cell and the real-time request power of the whole vehicle of the vehicle are monitored in the normal shutdown process of the fuel cell, and the emergency shutdown of the fuel cell is controlled when the real-time output power is larger than the real-time request power of the whole vehicle, so that the overcharge of the power cell can be more comprehensively prevented, and the power cell of the vehicle is protected.

In a possible implementation manner, the method further includes: when the output power is determined to be smaller than or equal to the request power of the whole vehicle, predicting whether an emergency load reduction working condition exists after a first preset duration of the vehicle; and when the emergency load reduction working condition of the vehicle is determined, controlling the emergency stop of the fuel cell, and prohibiting the fuel cell from starting.

The first preset duration may be any duration that is not equal to zero, which is not limited in the embodiment of the present application. And predicting whether the vehicle has an emergency load-shedding working condition after the preset time, namely predicting whether the vehicle has the emergency load-shedding working condition at any time.

The vehicle is in normal working condition in the normal running process, the user suddenly steps on the brake when driving the vehicle to run normally, or the vehicle can be in emergency load reduction working condition in the scene that the vehicle driven by the user runs from a flat road section to a long downhill slope and the like. At this time, the vehicle request power of the vehicle may be reduced below the output power of the fuel cell, even close to zero. The power output by the fuel cell can be recharged to the power cell, resulting in overcharging of the power cell. Namely, when the vehicle is in an emergency load-reducing working condition, the power battery can be overcharged.

The vehicle can predict whether an emergency load-reducing working condition exists after a preset time in the running process, and when the emergency load-reducing working condition exists after the preset time is predicted, the fuel cell is controlled to stop in advance, so that the power cell is prevented from being overcharged after the emergency load-reducing of the vehicle. Specifically, a sensor for collecting surrounding environment information of the vehicle can be arranged in the vehicle, the surrounding environment information of the vehicle can be collected in real time in the running process of the vehicle, and whether the vehicle has an emergency load reduction working condition can be predicted according to the surrounding environment information of the vehicle collected in real time.

And if the condition that the number of other vehicles on the road in front of the vehicle is more and the running speed is slower is determined according to the collected surrounding environment information, the vehicle is predicted to step on the brake after 5 seconds, and then the vehicle is predicted to have an emergency load reduction working condition after a first preset time period. Or determining that the vehicle cannot pass through the time when the traffic light of the intersection in front of the vehicle driving is red light or the time when the traffic light is left is green light according to the collected surrounding environment information, and predicting that the vehicle can step on the brake after 5s at the moment, so that the vehicle has an emergency load reduction working condition after the first preset time.

In some embodiments, the vehicle further includes a positioning module and a map module, and the vehicle may determine a current position of the vehicle according to the positioning module, and determine whether a long downhill exists on a road ahead of the vehicle according to the current position of the vehicle and the map included in the map module, and predict that an emergency load-shedding condition exists on the vehicle when the long downhill exists on the road ahead of the vehicle.

According to the method, when the output power is smaller than or equal to the request power of the whole vehicle, whether the vehicle has an emergency load-reducing working condition or not is predicted, and the emergency stop of the fuel cell is controlled in advance when the vehicle is predicted to have the emergency load-reducing working condition, so that the power cell of the vehicle can be further protected, and the power cell is prevented from being overcharged.

In summary, when the single voltage of the power battery is in an overvoltage state, the starting of the fuel battery is forbidden, so that the fuel battery does not work and does not output power under the condition that the single voltage of the power battery is in the overvoltage state, the condition that the power battery is overcharged due to the fact that the fuel battery charges the power battery is avoided, the frequency of emergency shutdown of the fuel battery under the scene can be reduced due to the fact that the starting of the fuel battery is forbidden, and the service life of the fuel battery is prolonged. The vehicle speed is smaller than the preset vehicle speed, power is not required, the power is output in the starting state of the fuel cell, the power output by the fuel cell charges the power cell, so that the power cell is overcharged, the emergency stop of the fuel cell is controlled, the power output by the fuel cell is cut off, the power cell of the vehicle can be protected, the overcharged power cell is prevented, the frequency of the emergency stop of the fuel cell can be reduced when the fuel cell is forbidden to start, and the fuel cell of the vehicle is protected. The real-time output power of the fuel cell and the real-time request power of the whole vehicle of the vehicle are monitored in the normal shutdown process of the fuel cell, and the emergency shutdown of the fuel cell is controlled when the real-time output power is larger than the real-time request power of the whole vehicle, so that the overcharge of the power cell can be more comprehensively prevented, and the power cell of the vehicle is protected. When the output power is smaller than or equal to the request power of the whole vehicle, whether the vehicle has an emergency load reduction working condition or not is predicted, and the fuel cell is controlled to stop in advance when the vehicle has the emergency load reduction working condition, so that the power cell of the vehicle can be further protected, and the power cell is prevented from being overcharged. By acquiring the single voltage of the power battery and comparing the single voltage with the preset threshold, and determining that the single voltage of the power battery is in an overvoltage state after the single voltage of the power battery is larger than the preset threshold and the single voltage exceeds the second preset time, the situation that the measured voltage value is larger than the preset threshold at a certain moment but the voltage value is rapidly reduced to be lower than the preset threshold can be avoided, and the current state of the power battery can be accurately judged.

Fig. 3 is a schematic structural diagram of an apparatus for overcharge protection of a power battery according to an embodiment of the present application.

Illustratively, as shown in FIG. 3, the apparatus 300 includes:

an acquisition module 301, configured to acquire a cell voltage value of a vehicle power battery;

a judging module 302, configured to judge whether a cell voltage of the power battery is in an overvoltage state;

the control module 303 is configured to prohibit the fuel cell of the vehicle from being started when it is determined that the cell voltage of the power cell is in an overvoltage state.

In a possible implementation manner, the control module 303 is specifically configured to: acquiring the current state of the fuel cell; controlling the fuel cell to stop and prohibiting the fuel cell from starting under the condition that the current state of the fuel cell is a starting state; and when the fuel cell is not in a starting state, prohibiting the fuel cell from starting.

In a possible implementation manner, the control module 303 is specifically configured to: acquiring the speed of the vehicle under the condition that the fuel cell is in a starting state; when the speed of the vehicle is smaller than the preset speed, the emergency stop of the fuel cell is controlled, and the starting of the fuel cell is forbidden.

In a possible implementation manner, the obtaining module 301 is further configured to obtain, when a vehicle speed of the vehicle is greater than a preset vehicle speed, an output power of the fuel cell and a vehicle request power of the vehicle; the control module 303 is further configured to control an emergency shutdown of the fuel cell and prohibit the fuel cell from being started when it is determined that the output power is greater than the request power of the whole vehicle; and when the output power is determined to be less than or equal to the request power of the whole vehicle, controlling the fuel cell to stop normally, and prohibiting the fuel cell from starting.

In a possible implementation manner, the apparatus further includes: the detection module is used for detecting whether the real-time output power of the fuel cell is larger than the real-time request power of the whole vehicle of the vehicle in the process of controlling the normal shutdown of the fuel cell; the control module 303 is further configured to control the fuel cell to be stopped in an emergency and inhibit the fuel cell from being started when the real-time output power is determined to be greater than the real-time request power of the whole vehicle.

In a possible implementation manner, the apparatus further includes: the prediction module is used for predicting whether an emergency load reduction working condition exists after a first preset duration of the vehicle when the output power is determined to be smaller than or equal to the request power of the whole vehicle; the control module 303 is further configured to control an emergency shutdown of the fuel cell and inhibit a start-up of the fuel cell when it is determined that an emergency load-shedding condition exists in the vehicle.

In one possible implementation, the determining module 302 is specifically configured to: judging whether the duration that the voltage value of the single body is larger than a preset threshold exceeds a second preset duration; and when the duration that the single voltage value is larger than the preset threshold value exceeds the second preset duration, determining that the single voltage of the power battery is in an overvoltage state.

Fig. 4 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Illustratively, as shown in FIG. 4, the vehicle 400 includes: the power battery overcharge protection system comprises a memory 401 and a processor 402, wherein executable program codes 4011 are stored in the memory 401, and the processor 402 is used for calling and executing the executable program codes 4011 to execute a power battery overcharge protection method.

In this embodiment, the vehicle may be divided into functional modules according to the above method example, for example, each functional module may be corresponding to a specific functional module, or two or more functions may be integrated into one processing module, where the integrated modules may be implemented in a hardware form. It should be noted that, in this embodiment, the division of the modules is schematic, only one logic function is divided, and another division manner may be implemented in actual implementation.

In the case of dividing each function module with corresponding each function, the vehicle may include: an acquisition module, a judgment module, a control module and the like. It should be noted that, all relevant contents of each step related to the above method embodiment may be cited to the functional description of the corresponding functional module, which is not described herein.

The vehicle provided in the present embodiment is used for executing the method for protecting the overcharge of the power battery, so that the same effect as the implementation method can be achieved.

In case an integrated unit is employed, the vehicle may comprise a processing module, a memory module. The processing module can be used for controlling and managing the actions of the vehicle. The memory module may be used to support the vehicle in executing, inter alia, program code and data.

Wherein the processing module may be a processor or controller that may implement or execute the various illustrative logical blocks, modules, and circuits described in connection with the present disclosure. A processor may also be a combination of computing functions, e.g., including one or more microprocessors, digital signal processing (digital signal processing, DSP) and microprocessor combinations, etc., and a memory module may be a memory.

The present embodiment also provides a computer readable storage medium having stored therein computer program code which, when run on a computer, causes the computer to perform the above-described related method steps to implement a method for power battery overcharge protection in the above-described embodiments.

The present embodiment also provides a computer program product which, when run on a computer, causes the computer to perform the above-described related steps to implement a method for overcharge protection of a power cell in the above-described embodiments.

In addition, the vehicle provided by the embodiment of the application can be a chip, a component or a module, and the vehicle can comprise a processor and a memory which are connected; the memory is used for storing instructions, and the processor can call and execute the instructions when the vehicle runs, so that the chip executes the method for protecting the overcharge of the power battery in the embodiment.

The vehicle, the computer readable storage medium, the computer program product or the chip provided in this embodiment are used to execute the corresponding method provided above, so that the benefits achieved by the method can refer to the benefits in the corresponding method provided above, and are not repeated herein.

It will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of modules or units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (10)

1. A method of overcharge protection of a power cell, the method comprising:

obtaining a single voltage value of a vehicle power battery;

judging whether the single voltage of the power battery is in an overvoltage state or not;

and prohibiting the fuel cell of the vehicle from starting under the condition that the single voltage of the power battery is determined to be in an overvoltage state.

2. The method of claim 1, wherein the disabling the fuel cell start-up of the vehicle comprises:

acquiring the current state of the fuel cell;

controlling the fuel cell to stop and prohibiting the fuel cell from starting under the condition that the current state of the fuel cell is a starting state;

and prohibiting the fuel cell from starting when the fuel cell is not in a starting state.

3. The method of claim 2, wherein controlling the fuel cell to stop and inhibit the fuel cell from starting while the fuel cell is in a start-up state comprises:

acquiring a vehicle speed of the vehicle when the fuel cell is in a start-up state;

and when the speed of the vehicle is smaller than a preset speed, controlling the fuel cell to stop in an emergency, and prohibiting the fuel cell from starting.

4. A method according to claim 3, characterized in that the method further comprises:

when the speed of the vehicle is greater than a preset speed, acquiring the output power of the fuel cell and the whole vehicle request power of the vehicle;

when the output power is determined to be larger than the request power of the whole vehicle, controlling the fuel cell to stop in an emergency mode, and prohibiting the fuel cell from starting;

and when the output power is determined to be smaller than or equal to the request power of the whole vehicle, controlling the fuel cell to stop normally, and prohibiting the fuel cell from starting.

5. The method according to claim 4, wherein the method further comprises:

detecting whether the real-time output power of the fuel cell is larger than the real-time request power of the whole vehicle of the vehicle in the process of controlling the normal shutdown of the fuel cell;

And when the real-time output power is determined to be larger than the real-time request power of the whole vehicle, controlling the fuel cell to stop in an emergency mode, and prohibiting the fuel cell from starting.

6. The method according to claim 4, wherein the method further comprises:

when the output power is determined to be smaller than or equal to the whole vehicle request power, predicting whether an emergency load reduction working condition exists after a first preset duration of the vehicle;

and when the emergency load reduction working condition of the vehicle is determined, controlling the fuel cell to stop in an emergency mode, and prohibiting the fuel cell from starting.

7. The method according to any one of claims 1 to 6, wherein the determining whether the cell voltage of the power battery is in an overvoltage state includes:

judging whether the duration that the single voltage value is larger than a preset threshold exceeds a second preset duration;

and when the duration that the single voltage value is larger than the preset threshold value exceeds the second preset duration, determining that the single voltage of the power battery is in an overvoltage state.

8. An apparatus for overcharge protection of a power cell, said apparatus comprising:

the acquisition module is used for acquiring the single voltage value of the vehicle power battery;

The judging module is used for judging whether the single voltage of the power battery is in an overvoltage state or not;

and the control module is used for prohibiting the starting of the fuel cell of the vehicle under the condition that the single voltage of the power cell is in an overvoltage state.

9. A vehicle, characterized in that the vehicle comprises:

a memory for storing executable program code;

a processor for calling and running the executable program code from the memory, causing the vehicle to perform the method of any one of claims 1 to 7.

10. A computer readable storage medium, characterized in that the computer readable storage medium stores a computer program which, when executed, implements the method according to any of claims 1 to 7.