Battery thermal management method and device in discharge scene and vehicle

Abstract

The invention relates to the technical field of vehicle control, and discloses a battery thermal management method and device in a discharge scenario and a vehicle, and the method comprises the steps: obtaining a driving working condition, a state of charge of a battery and a battery temperature, determining a battery thermal management threshold value of a battery thermal management system based on the driving working condition, and then obtaining a battery thermal management threshold value from a discharge scenario pulse spectrogram; determining the current state bit and the next state of charge of the battery based on the state of charge and the battery temperature, calculating the duration required by the decrease of the state of charge of the battery, and obtaining the target battery temperature corresponding to the next temperature calibration point from the discharge scene pulse spectrogram based on the current working state of the battery thermal management system, and calculating the temperature difference value between the battery temperature and the target battery temperature, and determining the target cooling water pump flow and the battery thermal management target power of the battery thermal management system based on the duration and the temperature difference value so as to control the battery thermal management system to execute operation, thereby realizing targeted adjustment of a thermal management strategy based on the current driving working condition.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a battery thermal management method and device in a discharge scenario and a vehicle. BACKGROUND

[0002] As the energy center of new energy vehicles, the electrochemical characteristics of power batteries directly restrict the power output performance and safety boundary of the whole vehicle. The inherent physicochemical properties of battery materials determine their temperature sensitivity. Whether in charging or discharging conditions, the temperature of the battery cell needs to be accurately controlled within the set optimal working interval. Exceeding this optimal working space will have a certain impact on the operation of the battery.

[0003] In the driving discharge scenario, the core task of the thermal management system is to dynamically adjust the battery temperature control strategy according to the power demand of the whole vehicle, maximize the power performance and available power under the premise of ensuring safe operation. However, the existing scheme relies on a static calibration strategy, which triggers temperature control actions through preset temperature thresholds. However, this method is highly dependent on engineering experience and vehicle calibration results, and has a large deviation, making it difficult to adapt to complex dynamic working conditions. SUMMARY

[0004] The present application provides a battery thermal management method, device and vehicle in a discharge scenario to solve the problem of existing static calibration strategy relying on engineering experience and vehicle calibration results.

[0005] In a first aspect, the present application provides a battery thermal management method in a discharge scenario, the method comprising: obtaining the current driving condition of the vehicle, the current state of charge of the battery and the current battery temperature, and determining the battery thermal management threshold of the battery thermal management system based on the current driving condition; based on the current state of charge and the current battery temperature, querying a preset discharge scenario map to determine the current state bit of the battery, wherein the map is constructed with the state of charge as the first coordinate and the battery temperature as the second coordinate, the direction of the first coordinate is opposite to the numerical change direction of the state of charge, and the direction of the second coordinate is the same as the numerical change direction of the battery temperature; based on the current state bit, obtaining the first state of charge corresponding to the next state of charge calibration point in the first coordinate direction from the discharge scenario map, and calculating the first time length required for the battery to reduce from the current state of charge to the first state of charge; based on the current state bit and the current working state of the battery thermal management system, obtaining the target battery temperature corresponding to the next temperature calibration point from the discharge scenario map, and calculating the temperature difference between the current battery temperature and the target battery temperature; based on the first time length and the temperature difference, determining the target cooling water pump flow of the battery thermal management system and the battery thermal management target power; based on the battery thermal management threshold, the target cooling water pump flow and the battery thermal management target power, controlling the battery thermal management system to perform battery thermal management operations.

[0006] The battery thermal management method in the discharge scenario provided by the application, by acquiring the current driving condition of the vehicle, the current state of charge of the battery and the current battery temperature, and based on the current driving condition, determining the battery thermal management threshold of the battery thermal management system, then from the discharge scenario map, based on the current state of charge and the current battery temperature, determining the current state bit of the battery, and determining the next state of charge, calculating the first duration required for the state of charge of the battery to drop, based on the current state bit and the current working state of the battery thermal management system, obtaining the target battery temperature corresponding to the next temperature calibration point from the discharge scenario map, and calculating the temperature difference between the current battery temperature and the target battery temperature, then based on the first duration and the temperature difference, determining the target cooling water pump flow of the battery thermal management system and the battery thermal management target power, to control the battery thermal management system to perform operation, realize the targeted adjustment of the thermal management strategy based on the current driving condition, and based on the determined temperature rise and the duration required for the state of charge to drop, optimize the operation of the battery thermal management system, improve the battery performance and vehicle energy efficiency, and avoid the problems of frequent heating start-stop, local temperature rise too high and large thermal power consumption caused by simple thermal management strategy, so that the system has higher reliability, reduces the thermal management power consumption, and extremely effectively saves the user's vehicle cost.

[0007] In an optional embodiment, the method further comprises: based on the current driving condition, determining the distribution proportion of energy consumption demand and power demand in the driving process; acquiring a first target cooling water pump flow and a first battery thermal management target power corresponding to the energy consumption demand scenario; acquiring a second target cooling water pump flow and a second battery thermal management target power corresponding to the power demand scenario; based on the distribution proportion of energy consumption demand and power demand, updating the target cooling water pump flow using the first target cooling water pump flow and the second target cooling water pump flow, and updating the battery thermal management target power using the first battery thermal management target power and the second battery thermal management target power.

[0008] The application differentiates the distribution proportion of economy and power for different conditions, and calculates the thermal management control parameters based on the proportion weight, to realize the accurate adaptation of multi-condition demand, so as to maximize the performance target.

[0009] In an alternative embodiment, the target battery temperature is a first battery temperature or a second battery temperature, the first battery temperature is a battery temperature corresponding to a next temperature calibration point in a second coordinate direction from the discharge scenario map, the second battery temperature is a battery temperature corresponding to a next temperature calibration point in a second coordinate reverse direction from the discharge scenario map, the current working state of the battery thermal management system is a cooling state or a heating state, and for the energy consumption demand scenario, the current working state is determined by the following steps: calculating a first thermal management power consumption threshold corresponding to the battery entering a first state bit from a current state bit, the first state bit being determined by a first state of charge and a current battery temperature; calculating a second thermal management power consumption threshold corresponding to the battery entering a second state bit from the current state bit, the second state bit being determined by the first state of charge and the first battery temperature; calculating a third thermal management power consumption threshold corresponding to the battery entering a third state bit from the current state bit, the third state bit being determined by the first state of charge and the second battery temperature; calculating a first difference between the second thermal management power consumption threshold and the first thermal management power consumption threshold; calculating a second difference between the third thermal management power consumption threshold and the first thermal management power consumption threshold; comparing the first difference and the second difference with a preset difference threshold respectively; if the first difference is not greater than the preset difference threshold and the second difference is greater than the preset difference threshold, it is determined that the battery thermal management system is in a heating state, and the preset difference threshold is a product of a preset discharge coefficient and a decay amount of the first state of charge and a current state of charge; if the first difference is greater than the preset difference threshold and the second difference is not greater than the preset difference threshold, it is determined that the battery thermal management system is in a cooling state; and if the first difference and the second difference are not greater than the preset difference threshold, based on a minimum difference between the first difference and the second difference, it is determined that the battery thermal management system is in the heating state or the cooling state.

[0010] The application establishes an energy consumption quantification determination standard for the energy consumption demand scenario, ensures that each heating or cooling operation meets the energy consumption economy requirement, and realizes accurate decision of thermal management action.

[0011] In an alternative embodiment, the method further comprises: if the first difference and the second difference are both greater than the preset difference threshold, controlling the battery thermal management system to be in a standby state to maintain the current temperature.

[0012] The application maintains the standby state of the battery thermal management system when it is determined that the battery thermal management system does not meet the economy requirement in the heating or cooling state, and reduces the invalid energy consumption of the thermal management system.

[0013] In an alternative embodiment, the state bit in the discharge scenario map represents the maximum allowed discharge current, and the current operating state is determined by the following steps: based on the first state bit, a corresponding first allowed discharge current is queried from the discharge scenario map, the first state bit being determined by the first state of charge and the current battery temperature; if the first allowed discharge current is not greater than the preset vehicle demand current, based on the second state bit, a corresponding second allowed discharge current is queried from the discharge scenario map, the second state bit being determined by the first state of charge and the first battery temperature; based on the third state bit, a corresponding third allowed discharge current is queried from the discharge scenario map, the third state bit being determined by the first state of charge and the second battery temperature; if the second allowed discharge current is greater than the preset vehicle demand current and the third allowed discharge current is not greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a heating state; if the second allowed discharge current is not greater than the preset vehicle demand current and the third allowed discharge current is greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a cooling state.

[0014] The application takes whether the allowed discharge current meets the vehicle demand current as the core determination basis, ensures that the thermal management action fully serves the power demand, maximizes the battery discharge capacity, and guarantees the continuous power output of the vehicle.

[0015] In an alternative embodiment, the method further comprises: if the second allowed discharge current and the third allowed discharge current are both greater than the preset vehicle demand current, performing the step of calculating the first thermal management power consumption threshold of the battery from the current state bit to the first state bit corresponding to the first state bit, and determining that the battery thermal management system is in a heating state or a cooling state.

[0016] The application can select the scheme with the least energy consumption to control the battery thermal management system to operate when both heating and cooling meet the vehicle power demand, accurately matches the core demands of continuous high power output in high-speed working conditions + as low invalid energy consumption as possible, avoids redundant energy consumption for maintaining unnecessary temperature, and indirectly improves the vehicle range.

[0017] In an alternative embodiment, the method further comprises: if the first allowed discharge current is greater than the preset vehicle demand current, controlling the battery thermal management system to be in a standby state to maintain the current temperature.

[0018] If the application determines that the first allowed discharge current meets the vehicle demand current, there is no need to adjust the temperature and other parameters, the battery thermal management system is controlled to be in a standby state to maintain the current temperature, which meets the vehicle power demand and reduces the invalid energy consumption caused by state bit switching.

[0019] In an optional implementation, the determining, based on the first time length and the temperature difference, of the target cooling water pump flow of the battery thermal management system and the battery thermal management target power comprises: calculating a ratio of the temperature difference to the first time length to obtain a target temperature change rate; and based on the target temperature change rate, in combination with a thermal model parameter of the battery, calculating the target cooling water pump flow and the battery thermal management target power so that, when the target cooling water pump flow and the battery thermal management target power are applied, the temperature change rate of the battery is equal to the target temperature change rate.

[0020] The application takes the target temperature change rate as a core control index, and derives the target power and the target cooling water pump flow of the battery thermal management system in combination with a thermal model parameter of the battery, thereby significantly improving the accuracy of temperature control and achieving closed-loop accurate matching of the time length and the temperature difference.

[0021] In an optional implementation, the obtaining of the current driving condition of the vehicle comprises: collecting vehicle driving data streams in a preset time period; dividing the vehicle driving data streams by a fixed time step to obtain a plurality of time windows, wherein each time window contains a time sequence of each parameter in the vehicle driving data streams; performing clustering analysis on the data in the plurality of time windows based on time sequence characteristics to determine a mapping relationship between clustering categories and driving conditions; and matching the time sequence characteristic data corresponding to the current time window with the mapping relationship between the clustering categories and the driving conditions to determine the current driving condition of the vehicle.

[0022] The application obtains driving data streams in a time period, divides the data by a fixed step to obtain a plurality of window data, performs clustering analysis on the plurality of window data to determine a mapping relationship between clustering categories and driving conditions, and then determines the current driving condition based on the time window to which the current time belongs, thereby realizing multi-dimensional data determination of the clustering categories of the driving condition and improving the accuracy and flexibility of condition determination.

[0023] In an optional implementation, the performing, based on time sequence characteristics, of clustering analysis on the data in the plurality of time windows to determine a mapping relationship between clustering categories and driving conditions comprises: based on each clustering category number in a selectable range of preset clustering category numbers, performing clustering analysis on the plurality of time window data based on time sequence characteristics to obtain a clustering result corresponding to each clustering category number; calculating the confidence of the clustering result corresponding to each clustering category number, and screening out a clustering result whose confidence satisfies a preset condition as an initial classification result; performing merging processing on categories with fuzzy category boundaries in the initial classification result; obtaining a condition category set; performing visual display on the condition category set to present the feature distribution and the category boundary of each condition category; based on the visual content, performing merging processing on categories with fuzzy category boundaries to determine the mapping relationship between the clustering categories and the driving conditions.

[0024] The application dynamically adapts the number of clustering categories, ensures that the size of the data set matches the number of clusters, improves the rationality of clustering in different data volume scenarios, then excludes classification results with low confidence through a confidence screening mechanism, improves the efficiency of subsequent boundary optimization, and ensures that the working condition category features are clear based on double boundary optimization, improves the stability and universality of driving working condition determination.

[0025] In a second aspect, the application provides a battery thermal management device in a discharge scenario, the device comprising: a parameter acquisition module for acquiring the current driving working condition of the vehicle, the current state of charge of the battery and the current battery temperature, and determining the battery thermal management threshold of the battery thermal management system based on the current driving working condition; a state bit determination module for querying a preset discharge scenario map based on the current state of charge and the current battery temperature, and determining the current state bit of the battery, wherein the map is constructed with the state of charge as the first coordinate and the battery temperature as the second coordinate, the direction of the first coordinate is opposite to the numerical change direction of the state of charge, and the direction of the second coordinate is the same as the numerical change direction of the battery temperature; a state of charge acquisition module for acquiring the first state of charge corresponding to the next state of charge calibration point in the first coordinate direction from the discharge scenario map based on the current state bit, and calculating the first time length required for the battery to reduce from the current state of charge to the first state of charge; a temperature difference calculation module for acquiring the target battery temperature corresponding to the next temperature calibration point from the discharge scenario map based on the current state bit and the current working state of the battery thermal management system, and calculating the temperature difference between the current battery temperature and the target battery temperature; a running parameter determination module for determining the target cooling water pump flow of the battery thermal management system and the battery thermal management target power based on the first time length and the temperature difference; and a thermal management system running module for controlling the battery thermal management system to perform battery thermal management operation based on the battery thermal management threshold, the target cooling water pump flow and the battery thermal management target power.

[0026] In a third aspect, the application provides a vehicle, comprising a controller, the controller comprising a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the battery thermal management method in a discharge scenario of the first aspect or any of the corresponding embodiments thereof.

[0027] The application has the following technical effects:

[0028] The application provides a battery thermal management method in a discharge scenario, which comprises the following steps: acquiring a current driving condition of a vehicle, a current state of charge of a battery and a current battery temperature; determining a battery thermal management threshold of a battery thermal management system based on the current driving condition; determining a current state bit of the battery based on the current state of charge and the current battery temperature, and determining a next state of charge from a discharge scenario map; calculating a first time length required for the state of charge of the battery to decrease; acquiring a target battery temperature corresponding to a next temperature calibration point from the discharge scenario map based on the current state bit and a current working state of the battery thermal management system, and calculating a temperature difference between the current battery temperature and the target battery temperature; and determining a target cooling water pump flow of the battery thermal management system and a battery thermal management target power based on the first time length and the temperature difference, so as to control the battery thermal management system to perform an operation, realize targeted adjustment of a thermal management strategy based on the current driving condition, optimize control of the operation of the thermal management system based on the determined temperature rise and time length required for the state of charge to decrease, improve battery performance and vehicle energy efficiency, and avoid problems such as frequent start-stop of heating, excessive local temperature rise and large thermal power consumption caused by a simple thermal management strategy, so that the system has higher reliability, thermal management power consumption is reduced, and user vehicle use cost is extremely effectively saved. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0030] Figure 1 FIG. 1 is a first flowchart of a battery thermal management method in a discharge scenario according to an embodiment of the present application; Figure 2 FIG. 2 is an example diagram of a discharge scenario map according to an embodiment of the present application; Figure 3 FIG. 3 is a second flowchart of a battery thermal management method in a discharge scenario according to an embodiment of the present application; Figure 4 FIG. 4 is an example diagram of a driving condition determination according to an embodiment of the present application; Figure 5 FIG. 5 is a specific flowchart example diagram of a battery thermal management method in a discharge scenario according to an embodiment of the present application; Figure 6 FIG. 6 is a structural block diagram of a vehicle according to an embodiment of the present application; Figure 7 FIG. 7 is a structural block diagram of a battery thermal management device in a discharge scenario according to an embodiment of the present application; Figure 8 Figure 1 is a schematic diagram of a hardware structure of a controller according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0032] The terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0033] Current whole vehicle thermal management system battery driving discharge battery thermal management strategy research has no longer been limited to starting heating and cooling at a fixed threshold, but has extended to consider whether heating is needed under specific working conditions and whether it is worth heating. However, there are still the following limitations in actual application: 1. Heating medium temperature control redundancy, increased energy consumption of battery thermal management system: In order to achieve the purpose of rapidly controlling the temperature of the battery, the current system usually heats or cools the heat transfer medium to a set value far exceeding the target temperature of the battery. However, after the battery reaches the target temperature, the battery self-heating effect and the cooling fluid convection heat transfer effect cause continuous heat input, the heating medium temperature control redundancy, the heat transfer medium still maintains a high / low temperature state exceeding the target temperature, the energy consumption of the battery thermal management system increases, which seriously restricts the economy and power of the battery.

[0034] 2. Lack of effective temperature prediction model in thermal management strategy: only according to the current collected temperature and charging and discharging state to calibrate the heating or cooling power, although the strategy is simple and more adaptable, but lack of system predictability, will cause energy consumption increase, local temperature rise too fast, thermal management device frequent start-stop and many other problems.

[0035] 3. Insufficient working condition adaptability: the current driving discharge thermal management system lacks differentiated thermal management strategies based on multiple scene requirements, and the existing scheme only linearly matches the single performance index (such as economy or power) of the battery as the optimization target; at the same time, the strategy decision mechanism has systematic defects, when using the threshold judgment method based on energy balance (such as comparing heating energy consumption and temperature control benefit), the static decision model cannot dynamically respond to the change of working condition demand.

[0036] According to the embodiment of the present application, a battery thermal management method in a discharge scenario is provided. It should be noted that the steps shown in the flowchart can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from here.

[0037] In this embodiment, a battery thermal management method in a discharge scenario is provided, which can be used for a controller in a vehicle, Figure 1 is a flowchart of the battery thermal management method in a discharge scenario according to the embodiment of the present application, as Figure 1 shown, the flow includes the following steps: Step S101, obtaining the current driving condition of the vehicle, the current state of charge of the battery and the current battery temperature, and determining the battery thermal management threshold of the battery thermal management system based on the current driving condition.

[0038] The embodiment of the present application can collect information such as power state, environment and road of vehicle driving (such as through vehicle sensor, vehicle electronic control unit reading and other ways), determine the current driving condition of the vehicle based on the collected information, such as the characteristics of frequent speed zero and high acceleration change in urban driving condition, the characteristics of continuous high speed and low acceleration fluctuation in high speed driving condition, the characteristics of continuous uphill and downhill and low temperature start in low temperature mountain driving condition, just as an example, the current state of charge (State of Charge, SOC) and the current battery temperature T of the battery can be obtained, and then the battery thermal management threshold of the battery thermal management system can be determined based on the pre-set thermal management strategy corresponding to different driving conditions, wherein the battery thermal management threshold includes heating threshold and cooling threshold, in specific embodiments, the designed thermal management strategy can include that in urban driving condition, the heating and cooling threshold is the safety working temperature threshold of the battery; in high speed driving condition, the heating and cooling threshold is the maximum value of discharge map (MAP) calculated by the preset model; in low temperature mountain condition, the heating and cooling threshold is the maximum value of the temperature threshold and the lowest temperature of the battery safety calculated by the high torque request power reverse lookup MAP table, to realize setting the corresponding battery thermal management threshold based on different driving conditions, which can be preloaded with thermal management strategy according to actual design, just as an example.

[0039] Step S102, based on the current state of charge and the current battery temperature, querying the preset discharge scenario map to determine the current state bit of the battery.

[0040] Wherein, the map is constructed with state of charge as the first coordinate and battery temperature as the second coordinate, the direction of the first coordinate is opposite to the numerical value change direction of the state of charge, and the direction of the second coordinate is the same as the numerical value change direction of the battery temperature.

[0041] The embodiment of the present application predefines a discharge scenario MAP diagram, as shown in the accompanying drawings, wherein the first coordinate (for example, the horizontal coordinate x) in the map is the state of charge (%), the second coordinate (for example, the vertical coordinate y) is the battery temperature (℃), the state bit (S) is determined by its position coordinate, in the MAP diagram, the direction of the first coordinate is opposite to the direction of the change of the value of the state of charge, that is, Figure 2 the right movement of SOC (SOC decrease) can be regarded as, the direction of the second coordinate is the same as the direction of the change of the value of the battery temperature, that is, the downward movement of temperature (temperature increase) can be regarded as.

[0042] After the current state of charge and the current battery temperature of the battery are obtained, the discharge scenario MAP diagram can be queried to determine the current state bit of the battery, which can be represented as S.

[0043] In step S103, based on the current state bit, the first state of charge corresponding to the next state of charge calibration point in the discharge scenario map along the direction of the first coordinate is obtained, and the first time length required for the battery to reduce from the current state of charge to the first state of charge is calculated.

[0044] Based on the current state bit (S), the first state of charge corresponding to the next state of charge calibration point in the discharge scenario map along the direction of the first coordinate is obtained, that is, S+1, and then the first time length t required for the battery to reduce from the current state of charge to the first state of charge can be calculated, wherein the way of calculating the first time length is not limited, for example, the difference between the two states of charge is calculated, the amount of electricity to be discharged is determined, and then divided by the average discharge current to obtain the first time length, which is only an example. In step S104, based on the current state bit and the current working state of the battery thermal management system, the target battery temperature corresponding to the next temperature calibration point in the discharge scenario map is obtained, and the temperature difference between the current battery temperature and the target battery temperature is calculated.

[0045]

[0046] ​​​The embodiment of the present application does not limit the way of determining whether the battery thermal management system (TMS) is in a heating state or a cooling state, for example, based on the current state of charge and the driving condition, the corresponding current scene optimal temperature interval is extracted from the preset three-dimensional interval of state of charge-condition-optimal temperature, and the thermal management threshold value under the driving condition is called, and then the current temperature is compared with the heating starting threshold value and the cooling starting threshold value to determine the working state of the battery thermal management system, wherein the working state determination rule can be dynamically corrected according to the actual driving condition, for example, the priority rule (such as safety priority, performance priority and energy saving priority corresponding to the working state determination rule) is used to correct the decision conflict in real time to avoid decision conflict, which is only an example.

[0047] If it is determined that the battery thermal management system is in a heating state, the next temperature calibration point corresponding to the target battery temperature along the second coordinate direction can be obtained from the discharge scene map, that is, Then the temperature difference between the target battery temperature and the current battery temperature is calculated as the temperature rise threshold.

[0048] If it is determined that the battery thermal management system is in a cooling state, the next temperature calibration point corresponding to the target battery temperature along the second coordinate direction can be obtained from the discharge scene map, that is, Then the temperature difference between the target battery temperature and the current battery temperature is calculated.

[0049] In step S105, the target cooling water pump flow of the battery thermal management system, the battery thermal management target power are determined based on the first time length and the temperature difference.

[0050] When it is determined that the battery thermal management system is in a heating state, the target cooling water pump flow of the battery thermal management system and the battery thermal management heating power can be determined based on the first time length and the temperature difference determined in the heating state, wherein the way of determining the target cooling water pump flow and the battery thermal management target power based on the first time length and the temperature difference is not limited, for example, the first time length and the temperature difference are standardized, and then the basic cooling water pump flow and the basic heating power are calculated based on the standardized two parameters through a preset three-dimensional map difference or a two-parameter coupling algorithm, and the target cooling water pump flow and the battery thermal management heating power can be obtained by adjusting the basic parameters through the corresponding correction coefficient combined with the current driving condition, the ambient temperature and the working condition fluctuation.

[0051] When it is determined that the battery thermal management system is in a cooling state, the target cooling water pump flow of the battery thermal management system and the battery thermal management cooling power can be determined based on the first time length and the temperature difference determined in the cooling state.

[0052] In step S106, the battery thermal management system is controlled to perform a battery thermal management operation based on the battery thermal management threshold, the target cooling water pump flow rate, and the battery thermal management target power.

[0053] The embodiment of the present application can control the battery thermal management system to perform a heating operation based on the battery thermal management threshold, the target cooling water pump flow rate, and the battery thermal management heating power, or control the battery thermal management system to perform a cooling operation based on the battery thermal management threshold, the target cooling water pump flow rate, and the battery thermal management cooling power.

[0054] The battery thermal management method in the discharging scenario provided by the present application can obtain the current driving condition of the vehicle, the current state of charge of the battery, and the current battery temperature, determine the battery thermal management threshold of the battery thermal management system based on the current driving condition, then determine the current state bit of the battery based on the current state of charge and the current battery temperature from the discharging scenario map, determine the next state of charge, calculate the first time length required for the state of charge of the battery to drop, obtain the target battery temperature corresponding to the next temperature calibration point from the discharging scenario map based on the current state bit and the current working state of the battery thermal management system, calculate the temperature difference between the current battery temperature and the target battery temperature, then determine the target cooling water pump flow rate of the battery thermal management system and the battery thermal management target power based on the first time length and the temperature difference, so as to control the battery thermal management system to perform an operation, realize the targeted adjustment of the thermal management strategy based on the current driving condition, and optimize the operation of the battery thermal management system based on the determined temperature rise and the time length required for the state of charge to drop, thereby improving the battery performance and the vehicle energy efficiency, avoiding the problems of frequent start-stop of heating, local temperature rise that is too high, and large thermal power consumption caused by simple thermal management strategies, making the system have higher reliability, reducing the thermal management power consumption, and greatly saving the user's vehicle cost.

[0055] In the present embodiment, a battery thermal management method in a discharging scenario is provided, which can be used for a controller in a vehicle, Figure 3 The flowchart of the battery thermal management method in the discharging scenario according to the embodiment of the present application is shown in Figure 3 The flowchart includes the following steps: In step S301, the current driving condition of the vehicle, the current state of charge of the battery, and the current battery temperature are obtained, and the battery thermal management threshold of the battery thermal management system is determined based on the current driving condition.

[0056] Specifically, the above step S301 includes: In step S3011, the vehicle driving data stream in a preset time period is collected.

[0057] Step S3012, the whole vehicle driving data stream is divided according to a fixed time step, and a plurality of time windows are obtained, wherein each time window contains the time sequence of each parameter in the whole vehicle driving data stream.

[0058] Step S3013, the data in the plurality of time windows is clustered based on the time sequence characteristics, and the mapping relationship between the cluster category and the driving condition is determined.

[0059] Step S3014, the current time window corresponding to the time sequence characteristic data is matched based on the mapping relationship between the cluster category and the driving condition, and the current driving condition of the vehicle is determined.

[0060] The application can collect the whole vehicle driving data stream in a preset time period, wherein the driving data stream can include but is not limited to time, speed, acceleration, motor torque, environmental temperature, battery state of charge, battery average temperature, discharge duration and thermal management power, etc. The multi-dimensional data is cooperated to reflect the vehicle driving state and the core system working characteristics, and more comprehensive and accurate input basis is provided for condition determination. Then, a fixed time step can be set to slice the whole vehicle driving data stream to obtain a plurality of time windows. The fixed time step can be set according to actual needs, and the window overlap rate can also be set to avoid missing the condition characteristics. Each time window contains the time sequence of the above-mentioned data stream used by the whole vehicle. Then, the time sequence data in each time window can be extracted to obtain core features such as statistical features (mean, peak, maximum value, etc.), trend features (linear fitting slope (such as speed rising / descending slope), trend duration, etc.) and mutation features (such as parameter mutation number (such as acceleration mutation number), mutation amplitude and frequency, etc.). In order to facilitate analysis, the feature data in the time window can be normalized, such as the speed range of [0, 1]. Part of the special condition data can be labeled, for example, the location of the whole vehicle is in the mountain area, to realize the accuracy of feature extraction and strengthen the distinguishability of the condition characteristics. Then, a clustering algorithm suitable for time sequence data can be selected for clustering, and the clustering result including the category is output. Finally, the mapping relationship between the cluster category and the driving condition is established, the clustering results of the current time window and the adjacent window are counted, and the current driving condition of the vehicle can be determined according to the majority voting principle or the weight weighting method, which is only an example.

[0061] The application obtains the driving data stream in a time period, divides the driving data stream according to a fixed step, obtains a plurality of window data, performs clustering analysis on the plurality of time window data, determines the mapping relationship between the cluster category and the driving condition, and then determines the current driving condition based on the time window to which the current time belongs, so as to realize the cluster category of the driving condition determined by the multi-dimensional data, and improve the accuracy and flexibility of the condition determination.

[0062] Further, based on the time sequence characteristics, the data in the plurality of time windows is subjected to clustering analysis to determine a mapping relationship between the clustering categories and the driving working conditions, including: based on each clustering category number in a selectable range of preset clustering category numbers, the data in the plurality of time windows is subjected to clustering analysis based on the time sequence characteristics to obtain a clustering result corresponding to each clustering category number; the confidence of the clustering result corresponding to each clustering category number is calculated, and a clustering result with a confidence satisfying a preset condition is selected as an initial classification result; a category with a fuzzy category boundary in the initial classification result is subjected to merging processing; a working condition category set is obtained; the working condition category set is subjected to visual display to present the feature distribution and the category boundary of each working condition category; based on the visual content, the category with the fuzzy category boundary is subjected to merging processing to determine the mapping relationship between the clustering categories and the driving working conditions.

[0063] As shown in Figure 4 To prevent the situation that the data set is small and the clustering number is large, in the clustering analysis, a selectable range of clustering category numbers can be set, for example, starting from 2 categories and ending at 10 categories, and then for the data in the plurality of time windows, each selectable clustering category number can be used for clustering analysis in turn to obtain a clustering result corresponding to each category number (i.e., different working condition classification schemes), and then the confidence of the clustering result corresponding to each clustering category number can be calculated, where the way of calculating the confidence is not limited, for example, a silhouette coefficient or other indicators can be used, based on a preset confidence threshold, a clustering result with a confidence satisfying the threshold is selected as an initial classification result to exclude a scheme with poor classification effect, and then the initial classification result can be subjected to boundary analysis to identify a situation that the category boundary is fuzzy, for example, if the feature overlap rate of two working conditions is greater than a certain value, a distance threshold method or a similarity fusion method can be used to merge the categories with the fuzzy boundary to obtain a working condition category set, and then the working condition category set can be subjected to visual processing to display a clearer clustering boundary, and the categories with the fuzzy boundary can be merged again to optimize the clarity of the working condition category set to ensure that each category corresponds to clear working condition features, and finally the working conditions with clear boundaries can be explained, i.e., a mapping relationship between the optimized working condition category set and the driving working conditions is established, for example, the clear working conditions include city driving: frequent speed return to zero and high acceleration change, high-speed driving: continuous high speed and low acceleration fluctuation, and low-temperature mountain area: vehicle speed is kept at a medium or low speed, high torque demand, and the environment temperature is less than 5℃, the time sequence feature data of the current time window is matched with the feature templates of the working condition categories to determine the current driving working condition of the vehicle, which is only an example.

[0064] The application dynamically adapts the number of clustering categories, ensures that the size of the data set matches the number of clusters, improves the rationality of clustering in different data volume scenarios, then excludes classification results with low confidence through a confidence screening mechanism, improves the efficiency of subsequent boundary optimization, and ensures that the working condition category features are clear based on double boundary optimization, thereby improving the stability and universality of driving working condition determination.

[0065] In step S302, the current state bit of the battery is determined by querying the preset discharge scenario map based on the current state of charge and the current battery temperature. For details, please refer to Figure 1 The step S102 of the embodiment shown will not be repeated here.

[0066] The map is constructed with the state of charge as the first coordinate and the battery temperature as the second coordinate, the direction of the first coordinate is opposite to the numerical change direction of the state of charge, and the direction of the second coordinate is the same as the numerical change direction of the battery temperature.

[0067] In step S303, the first state of charge corresponding to the next state of charge calibration point in the first coordinate direction is obtained from the discharge scenario map based on the current state bit, and the first time length required for the battery to reduce from the current state of charge to the first state of charge is calculated. For details, please refer to Figure 1 The step S103 of the embodiment shown will not be repeated here.

[0068] Further, the application preloads different thermal management strategies for different driving conditions, and the thermal management strategy also includes the allocation ratio of power and energy demand, specifically, based on the current driving condition, the allocation ratio of energy demand and power demand in the driving process is determined; the first target cooling water pump flow and the first battery thermal management target power corresponding to the energy demand scene are obtained; the second target cooling water pump flow and the second battery thermal management target power corresponding to the power demand scene are obtained; based on the allocation ratio of energy demand and power demand, the first target cooling water pump flow and the second target cooling water pump flow are used to update the target cooling water pump flow, and the first battery thermal management target power and the second battery thermal management target power are used to update the battery thermal management target power.

[0069] In the embodiments of the present application, the city driving condition, the high-speed driving condition and the low-temperature mountain condition are taken as examples, the economy and the power performance can be respectively set with weights based on the category difference to increase the condition adaptability of the thermal management scheme, for example, the economy of the city driving condition is set to 100%, the power performance of the high-speed driving condition is set to 100%, and the power performance and the economy of the low-temperature mountain condition are set to 1:1, then when the thermal management control is performed, the first target cooling water pump flow and the first battery thermal management target power corresponding to the energy consumption demand scenario can be calculated in the manner of calculating the target cooling water pump flow and the battery thermal management target power based on the above embodiments, the second target cooling water pump flow and the second battery thermal management target power corresponding to the power demand scenario are calculated, then the target cooling water pump flow and the battery thermal management target power are recalculated according to the distribution ratio of the energy consumption demand and the power demand, specifically, for the city driving condition, because the economy ratio is 100%, only the target cooling water pump flow and the battery thermal management target power under the energy consumption demand scenario need to be calculated, and the power demand scenario does not need to be calculated, as the parameter of controlling the battery thermal management system TMS, for the high-speed driving condition, because the power performance ratio is 100%, only the target cooling water pump flow and the battery thermal management target power under the power demand scenario need to be calculated, and the energy consumption demand scenario does not need to be calculated, as the parameter of controlling the battery thermal management system TMS, so that the operation process and the computing power consumption of the vehicle-mounted controller are greatly simplified on the premise of ensuring the control accuracy, and for the low-temperature mountain condition, the parameters corresponding to the energy consumption demand and the power demand scenarios are calculated respectively, then 50% of each is added to obtain the parameter of controlling the battery thermal management system TMS under the low-temperature mountain condition, which is only an example, and the effect of the new thermal management scheme can be verified to optimize the control strategy.

[0070] The present application differentiates the distribution ratio of the economy and the power performance according to different conditions, calculates the thermal management control parameter based on the ratio weight, realizes the accurate adaptation of the multi-condition demand, and maximizes the performance target.

[0071] In step S304, the target battery temperature corresponding to the next temperature calibration point is obtained from the discharge scene pulse diagram based on the current state bit and the current working state of the battery thermal management system, and the temperature difference between the current battery temperature and the target battery temperature is calculated.

[0072] The target battery temperature determined by the embodiment of the application is the first battery temperature or the second battery temperature, the current working state of the battery thermal management system is the cooling state or the heating state, and the current working state of the battery thermal management system is determined through the following steps according to the energy consumption demand scenario: the first thermal management power consumption threshold corresponding to the battery entering the first state point from the current state point is calculated, the first state point is determined by the first state of charge and the current battery temperature; the second thermal management power consumption threshold corresponding to the battery entering the second state point from the current state point is calculated, the second state point is determined by the first state of charge and the first battery temperature, and the first battery temperature is the battery temperature corresponding to the next temperature calibration point in the second coordinate direction obtained from the discharge scenario map; the third thermal management power consumption threshold corresponding to the battery entering the third state point from the current state point is calculated, the third state point is determined by the first state of charge and the second battery temperature, and the second battery temperature is the battery temperature corresponding to the next temperature calibration point in the reverse direction of the second coordinate obtained from the discharge scenario map; the first difference between the second thermal management power consumption threshold and the first thermal management power consumption threshold is calculated; the second difference between the third thermal management power consumption threshold and the first thermal management power consumption threshold is calculated; the first difference and the second difference are compared with the preset difference threshold respectively; if the first difference is not greater than the preset difference threshold and the second difference is greater than the preset difference threshold, it is determined that the battery thermal management system is in the heating state, and the preset difference threshold is the product of the preset discharge coefficient and the attenuation of the first state of charge and the current state of charge; if the first difference is greater than the preset difference threshold and the second difference is not greater than the preset difference threshold, it is determined that the battery thermal management system is in the cooling state; if the first difference and the second difference are not greater than the preset difference threshold, the battery thermal management system is determined to be in the heating state or the cooling state based on the minimum difference between the first difference and the second difference.

[0073] As Figure 5 shown, for the energy consumption demand scenario, that is, when the current driving condition of the whole vehicle is determined to be the urban driving condition after clustering analysis, TMS=3 is used to represent, the current state point (x0, y0) and the first state point (x1, y0), the second state point (x1, y1) and the third state point (x-1, y1) are obtained, and the specific process is as follows. Figure 2 ​​​As shown, assuming that the current state bit is (90%, -5℃), the first state bit is (80%, -5℃), the second state bit is (80%, 0℃), and the third state bit is (80%, -10℃), only as an example, then the first heat management power consumption threshold H0 corresponding to the battery entering the first state bit from the current state bit is calculated, the second heat management power consumption threshold H1 corresponding to the battery entering the second state bit from the current state bit is calculated, and the third heat management power consumption threshold H2 corresponding to the battery entering the third state bit from the current state bit is calculated, wherein the manner of calculating the heat management power consumption threshold is not limited, for example, the battery SOC is discharged from the current state of charge to the next state of charge (90% to 80%), the required time t (also expressed as the window time t) is calculated by the charging rate, and then the power required for the heat management to change (rise or fall) the cell temperature within the t time can be derived from the temperature estimation model, and the heat management power consumption threshold is calculated, only as an example.

[0074] Then, as shown in Figure 5 The embodiment of the present application can calculate the first difference value of the second heat management power consumption threshold and the first heat management power consumption threshold, that is, H1-H0, calculate the second difference value of the third heat management power consumption threshold and the first heat management power consumption threshold, that is, H2-H0, and then compare the two difference values with the preset difference threshold, respectively, wherein the preset difference threshold is the product of the preset discharge coefficient and the attenuation of the first state of charge and the current state of charge, that is, 10τ, as shown in Figure 2As shown, it can be known that the attenuation amount of the state of charge is 10%, the discharge coefficient τ can be set according to actual requirements, the unit is kWh / %, and only as an example; if the first difference is not greater than the preset difference, but the second difference is greater than the preset difference threshold, it can be determined that the energy consumption consumed by the battery temperature rising from the current battery temperature to the first battery temperature meets the energy consumption requirement, then the battery thermal management system can be controlled in a heating state, and then based on the temperature difference and the first time length, based on the battery thermal management system, the first time length is taken as the prediction time, the difference between the current battery temperature and the first battery temperature is taken as the temperature rise threshold, the target cooling water pump flow Q and the battery thermal management heating power P are calculated; if the first difference is greater than the preset difference, but the second difference is not greater than the preset difference threshold, it can be determined that the energy consumption consumed by the battery temperature decreasing from the current battery temperature to the second battery temperature meets the energy consumption requirement, then the battery thermal management system can be controlled in a cooling state, and then based on the temperature difference and the first time length, based on the battery thermal management system, the first time length is taken as the prediction time, the difference between the current battery temperature and the second battery temperature is taken as the temperature rise threshold, the target cooling water pump flow Q and the battery thermal management cooling power P are calculated to control the battery thermal management system to perform the cooling operation based on the calculated parameters; if the first difference and the second difference are both not greater than the preset difference threshold, it indicates that both schemes meet the energy consumption requirement, then it can be determined which one of the first difference and the second difference is smaller, and the state corresponding to the smaller difference is selected as the working state of the battery thermal management system, for example, the first difference is smaller than the second difference, then the battery thermal management system is controlled in a heating state to further reduce the invalid energy consumption of the battery thermal management system and prolong the vehicle cruising range, and the above scheme can be repeatedly judged in a period, the interval is To ensure that the currently determined working condition is the actual driving working condition, after the work is completed, the state function TMS=5 can be marked to the standby state, and when the vehicle is powered off, the state function TMS=0 can be marked to the powered-off state.

[0075] The present application establishes an energy consumption quantization judgment standard for energy consumption demand scenarios, ensures that each heating or cooling operation meets the energy consumption economic requirement, and realizes accurate decision of thermal management action.

[0076] In an optional embodiment, if the first difference and the second difference are both greater than the preset difference threshold, the battery thermal management system is controlled in a standby state to maintain the current temperature.

[0077] If the first difference and the second difference are both greater than the preset difference threshold 10τ in the embodiment of the present application, in order to reduce energy consumption and ensure economy, the battery thermal management system is controlled in a standby state to maintain the current temperature.

[0078] If the battery thermal management system does not meet the economic requirement in the heating or cooling state, the standby state of the battery thermal management system is maintained to reduce the invalid energy consumption of the thermal management system.

[0079] Specifically, the embodiment of the present invention designs a method for determining the target cooling water pump flow rate and the target power of the battery thermal management system based on a first duration and a temperature difference, including: calculating the ratio of the temperature difference to the first duration to obtain the target temperature change rate; and calculating the target cooling water pump flow rate and the target power of the battery thermal management system based on the target temperature change rate and the battery thermal model parameters, so that when the target cooling water pump flow rate and the target power of the battery thermal management system are applied, the battery temperature change rate is equal to the target temperature change rate.

[0080] like Figure 5 As shown, embodiments of the present invention can calculate the ratio of the temperature difference to the first time duration to obtain the target temperature change rate, i.e. Then, based on the target temperature change rate and combined with the battery's thermal model parameters, the target cooling water pump flow rate and the target battery thermal management power are calculated to ensure that, when the target cooling water pump flow rate and the target battery thermal management power are applied, the battery's temperature change rate equals the target temperature change rate. The specific calculation output is as follows: Make Where P1 represents the target power of battery thermal management calculated under any operating condition, and Q1 represents the target coolant pump flow rate calculated under any driving condition.

[0081] This invention uses the target temperature change rate as the core control indicator, and combines battery thermal model parameters to derive the target power and target cooling water pump flow rate of the thermal management system, significantly improving the accuracy of temperature control and achieving closed-loop precise matching of duration and temperature difference.

[0082] In one optional implementation, the state bit in the discharge scenario pulse spectrum diagram designed in this embodiment of the invention represents the maximum allowable discharge current. For power demand scenarios, the current operating state of the battery thermal management system can be determined through the following steps: Based on the first state bit, the corresponding first allowable discharge current is queried from the discharge scenario pulse spectrum diagram. The first state bit is determined by the first state of charge and the current battery temperature. If the first allowable discharge current is not greater than the preset vehicle demand current, based on the second state bit, the corresponding second allowable discharge current is queried from the discharge scenario pulse spectrum diagram. The second state bit is determined by the first state of charge and the first battery temperature. Based on the third state bit, the corresponding third allowable discharge current is queried from the discharge scenario pulse spectrum diagram. The third state bit is determined by the first state of charge and the second battery temperature. If the second allowable discharge current is greater than the preset vehicle demand current and the third allowable discharge current is not greater than the preset vehicle demand current, the battery thermal management system is determined to be in a heating state. If the second allowable discharge current is not greater than the preset vehicle demand current and the third allowable discharge current is greater than the preset vehicle demand current, the battery thermal management system is determined to be in a cooling state.

[0083] The embodiment of the present application is aimed at a power demand scene, that is, when it is determined that the current driving condition of the whole vehicle is a high-speed driving condition after clustering analysis, TMS=4 is used to represent, the current state bit (x0, y0) and the first state bit (x0+1, y0), the second state bit (x0+1, y0+1) and the third state bit (x0+1, y0-1) are obtained, and specifically, as shown in Figure 2 , it is assumed that the current state bit is (90%, -5℃), the first state bit is (80%, -5℃), the second state bit is (80%, 0℃) and the third state bit is (80%, -10℃), which are only examples, then the first allowed discharge current I0 corresponding to the first state bit, the second allowed discharge current I1 corresponding to the second state bit and the third allowed discharge current I2 corresponding to the third state bit are correspondingly queried from the discharge scene map, and then the allowed discharge currents corresponding to the state bits are compared with the whole vehicle demand current , wherein the whole vehicle demand current can be determined by the driving power, specifically, the driving power=UI, the driving power is obtained by the sum of the driving resistance, the rolling resistance, the acceleration resistance and the wind resistance multiplied by the vehicle speed, U is the total voltage of the battery, and I is the whole vehicle demand current, which is only an example.

[0084] The embodiment of the present application first determines whether the first allowed discharge current I0 meets the whole vehicle demand current, that is, I0 is greater than , if the first allowed discharge current meets the whole vehicle demand current, there is no need to adjust the temperature and other parameters, the battery thermal management system is controlled to be in a standby state to maintain the current temperature, which meets the whole vehicle power demand and reduces the invalid energy consumption caused by the state bit switching, if I0 does not meet the whole vehicle demand current, the sizes of the second allowed discharge current and the third allowed discharge current and the whole vehicle demand current can be determined, if the second allowed discharge current is greater than the preset whole vehicle demand current and the third allowed discharge current is not greater than the preset whole vehicle demand current, it is indicated that only the temperature rise can meet the whole vehicle power demand, and then the battery thermal management system can be controlled to be in a heating state, if the second allowed discharge current is not greater than the preset whole vehicle demand current and the third allowed discharge current is greater than the preset whole vehicle demand current, it is indicated that only the temperature drop can meet the whole vehicle power demand, and then the battery thermal management system can be controlled to be in a cooling state, then the temperature difference value can be calculated based on the working state of the battery thermal management system, the target cooling water pump flow of the battery thermal management system, the battery thermal management target power are determined based on the first time length and the temperature difference value corresponding to the state, and finally the battery thermal management system can be controlled to perform the heating or cooling operation.

[0085] The present application takes whether the allowed discharge current meets the whole vehicle demand current as the core determination basis, ensures that the thermal management action completely serves the power demand, maximizes the battery discharge capacity and guarantees the continuous power output of the whole vehicle.

[0086] In an optional embodiment, if the second allowable discharge current and the third allowable discharge current are both greater than the preset whole vehicle demand current, the step of calculating the first thermal management power consumption threshold corresponding to the first state bit from the current state bit is performed, and it is determined that the battery thermal management system is in a heating state or a cooling state.

[0087] If it is determined that the whole vehicle power demand is met regardless of heating or cooling, the heating and cooling corresponding thermal management power consumption parameters are calculated in sequence based on the above energy consumption demand scenarios, and the scheme with less thermal management power consumption is selected as the working state of the final battery thermal management system.

[0088] Then the ratio of the selected temperature difference and the first time length is calculated to obtain the target temperature change rate, that is, Then, based on the target temperature change rate, the target cooling water pump flow and the battery thermal management target power are calculated in combination with the thermal model parameters of the battery, so that when the target cooling water pump flow and the battery thermal management target power are applied, the temperature change rate of the battery is equal to the target temperature change rate. The specific calculation output is So that Wherein P1 represents the calculated battery thermal management target power under any working condition, Q1 represents the calculated target cooling water pump flow under any driving condition, and finally the calculated target cooling water pump flow and battery thermal management target power are used to control the operation of the battery thermal management system.

[0089] The present application can select the scheme with the least energy consumption to control the battery thermal management system to run when it is determined that heating or cooling meets the whole vehicle power demand, accurately matches the core demand of high power output under high speed working condition + reduces invalid energy consumption as much as possible, avoids redundant energy consumption for maintaining unnecessary temperature, and indirectly improves the cruising range of the whole vehicle.

[0090] Step S305, based on the first time length and the temperature difference, determining the target cooling water pump flow of the battery thermal management system and the battery thermal management target power. For details, please refer to Figure 1 The step S105 of the embodiment shown in the figure will not be repeated here.

[0091] Step S306, based on the battery thermal management threshold, the target cooling water pump flow and the battery thermal management target power, controlling the battery thermal management system to perform battery thermal management operation. For details, please refer to Figure 1 The step S106 of the embodiment shown in the figure will not be repeated here.

[0092] In one of the embodiments, the problem of frequent start-stop during driving caused by inaccurate control and battery power decline is avoided.

[0093] In one of the embodiments, the problem of significant reduction in cruising range caused by high-power heating when the drivable range is low is avoided.

[0094] The battery thermal management method in the discharge scenario designed by the application also has the following beneficial effects: 1. The application establishes an active thermal management technology based on power battery temperature prediction. By inputting the minimum temperature, maximum temperature, average temperature and environmental temperature of the battery, the TMS actively predicts the real-time change value of the battery temperature and the heating time to reach the specified temperature threshold, so as to maximize the discharge performance and minimize the thermal management energy consumption, dynamically adjust the heating power, cooling power and cooling water pump flow. By coupling the thermoelectric characteristics during discharge, the battery discharge characteristic map is linked to achieve optimal battery thermal management control; 2. The application clusters different discharge scenarios and working conditions of the power battery, and develops a thermal management strategy with economic and dynamic weight adaptation. In specific embodiments, the active adaptability of the thermal management strategy is realized. This method avoids the problems of heating redundancy, frequent start-stop and increased thermal management power consumption caused by simple thermal management strategies, so that the system has higher reliability, reduces thermal management power consumption, and effectively saves the user's vehicle cost.

[0095] In the embodiment, a vehicle is also provided, as shown in the figure, the vehicle comprises a controller 61 for executing the battery thermal management method in the discharge scenario described above. For details, please refer to the above embodiments, which will not be repeated here. Figure 6 In the embodiment, a vehicle is also provided, as shown in the figure, the vehicle comprises a controller 61 for executing the battery thermal management method in the discharge scenario described above. For details, please refer to the above embodiments, which will not be repeated here.

[0096] In the embodiment, a battery thermal management device in the discharge scenario is also provided, which is used to realize the above embodiments and preferred embodiments, and will not be repeated here. As used below, the term "module" can be a combination of software and / or hardware that realizes a predetermined function. Although the device described in the following embodiments is preferably realized in software, hardware or a combination of software and hardware is also possible and is conceived.

[0097] The embodiment provides a battery thermal management device in the discharge scenario, as shown in the figure, the device comprises a controller 61 for executing the battery thermal management method in the discharge scenario described above. Figure 7As shown, the method comprises: a parameter acquisition module 701, configured to acquire a current driving condition of a vehicle, a current state of charge of a battery and a current battery temperature, and determine a battery thermal management threshold of a battery thermal management system based on the current driving condition; a state bit determination module 702, configured to query a preset discharge scenario map based on the current state of charge and the current battery temperature, and determine a current state bit of the battery, wherein the map is constructed with the state of charge as a first coordinate and the battery temperature as a second coordinate, the direction of the first coordinate is opposite to the numerical change direction of the state of charge, and the direction of the second coordinate is the same as the numerical change direction of the battery temperature; a state of charge acquisition module 703, configured to acquire a first state of charge corresponding to a next state of charge calibration point in the direction of the first coordinate from the discharge scenario map based on the current state bit, and calculate a first time length required for the battery to reduce from the current state of charge to the first state of charge; a temperature difference calculation module 704, configured to acquire a target battery temperature corresponding to a next temperature calibration point from the discharge scenario map based on the current state bit and a current working state of the battery thermal management system, and calculate a temperature difference between the current battery temperature and the target battery temperature; a running parameter determination module 705, configured to determine a target cooling water pump flow of the battery thermal management system and a battery thermal management target power based on the first time length and the temperature difference; and a thermal management system running module 706, configured to control the battery thermal management system to perform a battery thermal management operation based on the battery thermal management threshold, the target cooling water pump flow and the battery thermal management target power.

[0098] In some optional embodiments, the battery thermal management device under the discharge scenario further comprises: a distribution ratio determination module, configured to determine a distribution ratio of energy consumption demand and power demand in the driving process based on the current driving condition; an energy consumption scenario parameter acquisition module, configured to acquire a first target cooling water pump flow and a first battery thermal management target power corresponding to the energy consumption demand scenario; a power demand scenario parameter acquisition module, configured to acquire a second target cooling water pump flow and a second battery thermal management target power corresponding to the power demand scenario; and a parameter determination module, configured to update the target cooling water pump flow by using the first target cooling water pump flow and the second target cooling water pump flow based on the distribution ratio of the energy consumption demand and the power demand, and update the battery thermal management target power by using the first battery thermal management target power and the second battery thermal management target power.

[0099] In some optional embodiments, the target battery temperature is a first battery temperature or a second battery temperature, the first battery temperature is a battery temperature corresponding to a next temperature calibration point in a second coordinate direction from the discharge scenario map, the second battery temperature is a battery temperature corresponding to a next temperature calibration point in a second coordinate reverse direction from the discharge scenario map, the current working state of the battery thermal management system is a cooling state or a heating state, and the current working state is determined according to the energy consumption demand scenario by the following steps: calculating a first thermal management power consumption threshold corresponding to a first state bit of the battery from a current state bit, the first state bit being determined by the first state of charge and the current battery temperature; calculating a second thermal management power consumption threshold corresponding to a second state bit of the battery from the current state bit, the second state bit being determined by the first state of charge and the first battery temperature; calculating a third thermal management power consumption threshold corresponding to a third state bit of the battery from the current state bit, the third state bit being determined by the first state of charge and the second battery temperature; calculating a first difference between the second thermal management power consumption threshold and the first thermal management power consumption threshold; calculating a second difference between the third thermal management power consumption threshold and the first thermal management power consumption threshold; comparing the first difference and the second difference with a preset difference threshold respectively; if the first difference is not greater than the preset difference threshold and the second difference is greater than the preset difference threshold, determining that the battery thermal management system is in the heating state, the preset difference threshold being a product of a preset discharge coefficient and a decay amount of the first state of charge and the current state of charge; if the first difference is greater than the preset difference threshold and the second difference is not greater than the preset difference threshold, determining that the battery thermal management system is in the cooling state; and if the first difference and the second difference are not greater than the preset difference threshold, determining that the battery thermal management system is in the heating state or the cooling state based on a minimum difference between the first difference and the second difference.

[0100] In some optional embodiments, the battery thermal management device under the discharge scenario further comprises a standby maintaining module configured to control the battery thermal management system to be in a standby state to maintain the current temperature if the first difference and the second difference are both greater than the preset difference threshold.

[0101] In some optional embodiments, the state bit in the discharge scenario map represents a maximum allowed discharge current, and the current working state is determined for a power demand scenario by the following steps: based on a first state bit, a corresponding first allowed discharge current is queried from the discharge scenario map, the first state bit being determined by a first state of charge and a current battery temperature; if the first allowed discharge current is not greater than a preset vehicle demand current, based on a second state bit, a corresponding second allowed discharge current is queried from the discharge scenario map, the second state bit being determined by the first state of charge and the first battery temperature; based on a third state bit, a corresponding third allowed discharge current is queried from the discharge scenario map, the third state bit being determined by the first state of charge and a second battery temperature; if the second allowed discharge current is greater than the preset vehicle demand current and the third allowed discharge current is not greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a heating state; if the second allowed discharge current is not greater than the preset vehicle demand current and the third allowed discharge current is greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a cooling state.

[0102] In some optional embodiments, the battery thermal management device under the discharge scenario further includes an energy consumption comparison module configured to, if the second allowed discharge current and the third allowed discharge current are both greater than the preset vehicle demand current, perform a step of calculating a first thermal management energy consumption threshold of the battery from a current state bit to a first state bit corresponding to the first allowed discharge current, and determine that the battery thermal management system is in the heating state or the cooling state.

[0103] In some optional embodiments, the battery thermal management device under the discharge scenario further includes a standby keeping module configured to, if the first allowed discharge current is greater than the preset vehicle demand current, control the battery thermal management system to be in a standby state to maintain the current temperature.

[0104] In some optional embodiments, the running parameter determination module 705 includes a rate of change calculation unit configured to calculate a ratio of the temperature difference value to the first time length to obtain a target temperature change rate; and a parameter calculation unit configured to calculate, based on the target temperature change rate and in combination with a thermal model parameter of the battery, a target cooling water pump flow rate and a battery thermal management target power, so that when the target cooling water pump flow rate and the battery thermal management target power are applied, the temperature change rate of the battery is equal to the target temperature change rate.

[0105] In some optional embodiments, the parameter acquisition module 701 comprises: a data collection unit configured to collect a vehicle driving data stream in a preset time period; a window division unit configured to divide the vehicle driving data stream according to a fixed time step to obtain a plurality of time windows, wherein each time window contains a time sequence of each parameter in the vehicle driving data stream; a data clustering unit configured to perform clustering analysis on data in the plurality of time windows based on time sequence characteristics to determine a mapping relationship between clustering categories and driving conditions; and a condition determination unit configured to determine a current driving condition of the vehicle based on matching of time sequence characteristic data corresponding to a current time window and the mapping relationship between clustering categories and driving conditions.

[0106] In some optional embodiments, the data clustering unit comprises: a clustering category division subunit configured to perform clustering analysis on the plurality of time window data based on time sequence characteristics according to each clustering category number in a selectable range of preset clustering category numbers to obtain a clustering result corresponding to each clustering category number; a confidence degree calculation subunit configured to calculate a confidence degree of the clustering result corresponding to each clustering category number and to select a clustering result with a confidence degree satisfying a preset condition as an initial classification result; a category merging subunit configured to perform merging processing on categories with fuzzy category boundaries in the initial classification result to obtain a condition category set; the category merging subunit is configured to visually display the condition category set to present characteristic distribution and category boundaries of each condition category; and a mapping relationship determination subunit configured to perform merging processing on categories with fuzzy category boundaries based on the visual content to determine the mapping relationship between the clustering categories and the driving conditions.

[0107] The battery thermal management device in the discharge scenario provided by the embodiments of the present application can execute the battery thermal management method in the discharge scenario provided by any of the embodiments of the present application, and has the corresponding function modules and beneficial effects of the execution method. The further function description of each module and unit is the same as that of the corresponding embodiments described above, and will not be repeated here.

[0108] Figure 8 A structural schematic diagram of a controller provided by the embodiments of the present application.

[0109] The following will be specifically described with reference to Figure 8Fig. 8 shows a block diagram of a controller suitable for use in implementing the controller in embodiments of the present application. The controller can include a processor (e.g., a central processing unit, a graphics processing unit, etc.) 801 that can perform various appropriate actions and processes according to programs stored in a read-only memory (ROM) 802 or loaded from a memory 808 into a random access memory (RAM) 803. Various programs and data required for the controller operation are also stored in the RAM 803. The processor 801, the ROM 802, and the RAM 803 are connected to each other through a bus 804. An input / output (I / O) interface 805 is also connected to the bus 804.

[0110] Generally, the following devices can be connected to the I / O interface 805: input devices 806 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; output devices 807 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage 808 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 809. The communication device 809 can allow the controller to communicate wirelessly or wired with other devices to exchange data. Although Figure 8 The controller is shown with various devices, but it should be understood that all of the shown devices are not required, and more or less devices can alternatively be implemented.

[0111] In particular, the processes described above with reference to the flowcharts can be implemented as a computer software program according to embodiments of the present application. For example, embodiments of the present application include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods illustrated by the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network through the communication device 809, or installed from the storage 808, or installed from the ROM 802. When the computer program is executed by the processor 801, the above-described functions defined in the battery thermal management method in the discharge scenario of embodiments of the present application are performed.

[0112] Figure 8 The controller shown is merely an example and should not impose any limitations on the functions and the scope of use of embodiments of the present application.

[0113] The embodiments of the present application further provide a computer readable storage medium, and the method according to the embodiments of the present application can be implemented in hardware, firmware, or recorded in a storage medium, or stored in a remote storage medium or a non-transitory machine readable storage medium and downloaded to a local storage medium through network, so that the method described herein can be processed by such software on a storage medium using a general purpose computer, a special purpose processor, or programmable or special hardware. The storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid state disk, etc. Further, the storage medium can also include a combination of the above-mentioned memories. It can be understood that the computer, the processor, the microprocessor controller, or the programmable hardware includes a storage component that can store or receive software or computer code, when the software or computer code is accessed and executed by the computer, the processor, or the hardware, the battery thermal management method in the discharge scenario shown in the above embodiments is implemented.

[0114] Part of the present application can be applied as a computer program product, for example, computer program instructions, when executed by a computer, through the operation of the computer, the method and / or technical solutions according to the present application can be called or provided. Those skilled in the art should understand that the form of computer program instructions in a computer readable medium includes but is not limited to source files, executable files, installation package files, etc. Correspondingly, the way of executing computer program instructions by computer includes but is not limited to: the computer directly executes the instructions, or the computer compiles the instructions and then executes the corresponding compiled program, or the computer reads and executes the instructions, or the computer reads and installs the instructions and then executes the corresponding installed program. Here, the computer readable medium can be any available computer readable storage medium or communication medium accessible to the computer.

[0115] Although the embodiments of the present application are described in conjunction with the accompanying drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A battery thermal management method under a discharge scenario, characterized in that, The method includes: The vehicle's current driving conditions, the battery's current state of charge, and the current battery temperature are obtained, and based on the current driving conditions, the battery thermal management threshold of the battery thermal management system is determined. Based on the current state of charge and the current battery temperature, a preset discharge scenario pulse spectrum is queried to determine the current state of the battery. The pulse spectrum is constructed with the state of charge as the first coordinate and the battery temperature as the second coordinate. The direction of the first coordinate is opposite to the direction of the numerical change of the state of charge, and the direction of the second coordinate is the same as the direction of the numerical change of the battery temperature. Based on the current state position, the first state of charge corresponding to the next state of charge calibration point along the first coordinate direction is obtained from the discharge scenario pulse spectrum diagram, and the first time required for the battery to reduce from the current state of charge to the first state of charge is calculated. Based on the current state bit and the current working state of the battery thermal management system, the target battery temperature corresponding to the next temperature calibration point is obtained from the discharge scenario pulse spectrum, and the temperature difference between the current battery temperature and the target battery temperature is calculated. Based on the first duration and the temperature difference, the target cooling water pump flow rate and the target power of the battery thermal management system are determined. Based on the battery thermal management threshold, the target cooling water pump flow rate, and the battery thermal management target power, the battery thermal management system is controlled to perform battery thermal management operations.

2. The method according to claim 1, characterized in that, The method further includes: Based on the current driving conditions, determine the proportion of energy consumption and power demand during the driving process; Obtain the first target cooling water pump flow rate and the first target battery thermal management power corresponding to the energy consumption demand scenario; Obtain the second target cooling water pump flow rate and the second target power for battery thermal management corresponding to the power demand scenario; Based on the allocation ratio of energy consumption demand and power demand, the target cooling water pump flow rate is updated using the first target cooling water pump flow rate and the second target cooling water pump flow rate, and the battery thermal management target power is updated using the first battery thermal management target power and the second battery thermal management target power.

3. The method according to claim 2, characterized in that, The target battery temperature is either a first battery temperature or a second battery temperature. The first battery temperature is the battery temperature corresponding to the next temperature calibration point along the second coordinate direction obtained from the discharge scenario pulse spectrum. The second battery temperature is the battery temperature corresponding to the next temperature calibration point along the opposite direction of the second coordinate obtained from the discharge scenario pulse spectrum. The current operating state of the battery thermal management system is either a cooling state or a heating state. For energy consumption demand scenarios, the current operating state is determined through the following steps: Calculate the first thermal management power consumption threshold corresponding to the battery transitioning from the current state to the first state, where the first state is determined by the first state of charge and the current battery temperature; Calculate the second thermal management power consumption threshold corresponding to the battery transitioning from the current state to the second state, where the second state is determined by the first state of charge and the first battery temperature; Calculate the third thermal management power consumption threshold corresponding to the battery transitioning from the current state to the third state, wherein the third state is determined by the first state of charge and the second battery temperature; Calculate the first difference between the second thermal management power consumption threshold and the first thermal management power consumption threshold; Calculate the second difference between the third thermal management power consumption threshold and the first thermal management power consumption threshold; The first difference and the second difference are compared with preset difference thresholds respectively; If the first difference is not greater than the preset difference threshold, and the second difference is greater than the preset difference threshold, it is determined that the battery thermal management system is in a heating state. The preset difference threshold is the product of the preset discharge coefficient and the attenuation amount of the first state of charge and the current state of charge. If the first difference is greater than the preset difference threshold and the second difference is not greater than the preset difference threshold, it is determined that the battery thermal management system is in a cooling state. If neither the first difference nor the second difference is greater than the preset difference threshold, the battery thermal management system is determined to be in a heating or cooling state based on the minimum difference between the first difference and the second difference.

4. The method according to claim 3, characterized in that, The method further includes: If both the first difference and the second difference are greater than the preset difference threshold, the battery thermal management system is controlled to be in standby mode to maintain the current temperature.

5. The method according to claim 3, characterized in that, The state bit in the discharge scenario pulse spectrum diagram represents the maximum allowable discharge current. For power demand scenarios, the current operating state is determined through the following steps: Based on the first state bit, the corresponding first allowable discharge current is queried from the discharge scenario pulse spectrum diagram. The first state bit is determined by the first state of charge and the current battery temperature. If the first allowable discharge current is not greater than the preset vehicle demand current, the corresponding second allowable discharge current is queried from the discharge scenario pulse spectrum based on the second state bit. The second state bit is determined by the first state of charge and the first battery temperature. Based on the third state bit, the corresponding third allowable discharge current is queried from the discharge scenario pulse spectrum diagram. The third state bit is determined by the first state of charge and the second battery temperature. If the second allowable discharge current is greater than the preset vehicle demand current and the third allowable discharge current is not greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a heating state. If the second allowable discharge current is not greater than the preset vehicle demand current, and the third allowable discharge current is greater than the preset vehicle demand current, it is determined that the battery thermal management system is in a cooling state.

6. The method according to claim 5, characterized in that, The method further includes: If both the second allowable discharge current and the third allowable discharge current are greater than the preset vehicle demand current, the step of calculating the first thermal management power consumption threshold corresponding to the battery entering the first state from the current state is executed to determine whether the battery thermal management system is in a heating state or a cooling state.

7. The method according to claim 5, characterized in that, The method further includes: If the first allowable discharge current is greater than the preset vehicle demand current, the battery thermal management system is controlled to be in standby mode to maintain the current temperature.

8. The method according to claim 1, characterized in that, The step of determining the target cooling water pump flow rate and target battery thermal management power of the battery thermal management system based on the first duration and the temperature difference includes: The ratio of the temperature difference to the first duration is calculated to obtain the target temperature change rate; Based on the target temperature change rate and combined with the battery's thermal model parameters, the target cooling water pump flow rate and the target battery thermal management power are calculated so that when the target cooling water pump flow rate and the target battery thermal management power are applied, the battery's temperature change rate is equal to the target temperature change rate.

9. The method according to claim 1, characterized in that, The acquisition of the vehicle's current driving conditions includes: Collect vehicle driving data streams within a preset time period; The vehicle driving data stream is divided into multiple time windows according to a fixed time step, wherein each time window contains the time sequence of each parameter in the vehicle driving data stream; For the data within the multiple time windows, cluster analysis is performed based on time series characteristics to determine the mapping relationship between cluster categories and driving conditions; The current driving condition of the vehicle is determined by matching the time-series feature data corresponding to the current time window with the mapping relationship between the cluster category and the driving condition.

10. The method according to claim 9, characterized in that, The step of performing cluster analysis on the data within the multiple time windows based on time series features to determine the mapping relationship between cluster categories and driving conditions includes: Based on the number of each cluster category within a preset range of selectable cluster categories, cluster analysis is performed on multiple time window data based on time series features to obtain clustering results corresponding to each number of cluster categories; Calculate the confidence score of the clustering results corresponding to the number of clusters in each cluster, and select the clustering results whose confidence scores meet the preset conditions as the initial classification results; The categories with ambiguous boundaries in the initial classification results are merged to obtain a set of working condition categories; The set of working condition categories is visualized to present the feature distribution and category boundaries of each working condition category; Based on the visualized content, categories with blurred boundaries are merged to determine the mapping relationship between cluster categories and driving conditions.

11. A battery thermal management device for a discharge scenario, characterized in that, The device includes: The parameter acquisition module is used to acquire the vehicle's current driving conditions, the battery's current state of charge, and the current battery temperature, and to determine the battery thermal management threshold of the battery thermal management system based on the current driving conditions. The state position determination module is used to query a preset discharge scenario pulse spectrum based on the current state of charge and the current battery temperature to determine the current state position of the battery. The pulse spectrum is constructed with the state of charge as the first coordinate and the battery temperature as the second coordinate. The direction of the first coordinate is opposite to the direction of the numerical change of the state of charge, and the direction of the second coordinate is the same as the direction of the numerical change of the battery temperature. The state of charge acquisition module is used to obtain the first state of charge corresponding to the next state of charge calibration point along the first coordinate direction from the discharge scenario pulse spectrum based on the current state position, and calculate the first time required for the battery to reduce to the first state of charge based on the current state of charge. The temperature difference calculation module is used to obtain the target battery temperature corresponding to the next temperature calibration point from the discharge scenario pulse spectrum based on the current state bit and the current working state of the battery thermal management system, and to calculate the temperature difference between the current battery temperature and the target battery temperature. The operating parameter determination module is used to determine the target cooling water pump flow rate and the target power of the battery thermal management system based on the first duration and the temperature difference. The thermal management system operation module is used to control the battery thermal management system to perform battery thermal management operations based on the battery thermal management threshold, the target cooling water pump flow rate, and the battery thermal management target power.

12. A vehicle, characterized in that, The vehicle includes a controller, which includes a memory and a processor. The memory and the processor are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to perform the battery thermal management method under the discharge scenario according to any one of claims 1 to 10.

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