A battery temperature control method and device, a storage medium and a battery management system

Abstract

The application belongs to the technical field of batteries, and particularly relates to a battery temperature control method and device, a computer readable storage medium and a battery management system. The method comprises the following steps: obtaining a current control temperature of a passenger compartment of a vehicle and a target control temperature of the passenger compartment; calculating a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment; and controlling a battery temperature of the vehicle according to the first temperature difference. According to the application, instead of merely focusing on the battery itself, the temperature control of the battery and the temperature control of the passenger compartment are regarded as an organic whole, so that the adverse effect of the temperature control of the passenger compartment caused by one-sided pursuit of the best battery temperature control effect is avoided, and the use experience of passengers can be effectively improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and particularly relates to a battery temperature control method and device, a computer readable storage medium, and a battery management system. BACKGROUND

[0002] With the increasingly serious energy and environmental problems, the concept of energy saving and environmental protection is deeply rooted in people's minds. Electric vehicles have significant advantages in energy saving and environmental protection, and have attracted worldwide attention. As a power source, the power battery is one of the core components of an electric vehicle. Due to the inherent characteristics of the power battery, temperature has a great influence on the charging and discharging capacity of the power battery, which can directly affect the performance of the vehicle and also affect the service life of the power battery.

[0003] There are relatively mature battery temperature control methods in the prior art, which can effectively control the battery temperature within a suitable range, ensure that the temperature difference of the battery changes little, and prolong the service life of the battery. However, these temperature control methods often only focus on the battery itself, and in order to obtain the best battery temperature control effect, they may even adversely affect other aspects of the vehicle performance, thereby causing poor user experience for passengers. SUMMARY

[0004] Therefore, the embodiments of the present application provide a battery temperature control method, device, computer readable storage medium and battery management system to solve the problem that the existing battery temperature control method often only focuses on the battery itself, and in order to obtain the best battery temperature control effect, it may even adversely affect other aspects of the vehicle performance, thereby causing poor user experience for passengers.

[0005] The first aspect of the embodiments of the present application provides a battery temperature control method, which can include:

[0006] obtaining a current control temperature of a passenger compartment of a vehicle and a target control temperature of the passenger compartment;

[0007] calculating a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment;

[0008] controlling a battery temperature of the vehicle according to the first temperature difference.

[0009] In a specific implementation manner of the first aspect, the controlling of the battery temperature of the vehicle according to the first temperature difference can include:

[0010] determining a temperature difference threshold corresponding to the battery temperature control mode;

[0011] controlling the battery temperature of the vehicle according to the first temperature difference and the temperature difference threshold.

[0012] In a specific implementation manner of the first aspect, the battery temperature control mode is the refrigeration mode; and the controlling the battery temperature of the vehicle according to the first temperature difference and the temperature difference threshold can include:

[0013] controlling the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold; wherein the first flow control component is configured to control the flow of the refrigerant for refrigerating the battery.

[0014] In a specific implementation manner of the first aspect, the controlling the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold can include:

[0015] if the first temperature difference is less than the temperature difference threshold, obtaining the battery water inlet temperature, and determining a refrigeration target water temperature corresponding to the refrigeration mode;

[0016] calculating a second temperature difference between the battery water inlet temperature and the refrigeration target water temperature;

[0017] controlling the opening degree of the first flow control component according to the second temperature difference; wherein the opening degree of the first flow control component is positively correlated with the second temperature difference.

[0018] In a specific implementation manner of the first aspect, the controlling the opening degree of the first flow control component according to the second temperature difference can include:

[0019] using a proportional-integral control algorithm to control the opening degree of the first flow control component with the second temperature difference as an error amount.

[0020] In a specific implementation manner of the first aspect, the controlling the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold can include:

[0021] if the first temperature difference is greater than or equal to the temperature difference threshold, gradually reducing the opening degree of the first flow control component until it is reduced to a minimum opening degree corresponding to the refrigeration mode.

[0022] In a specific implementation manner of the first aspect, the battery temperature control mode is the heating mode; and the controlling the battery temperature of the vehicle according to the first temperature difference and the temperature difference threshold can include:

[0023] controlling the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold; wherein the second flow control component is configured to control the flow of the coolant for heating the battery.

[0024] In a specific implementation manner of the first aspect, the controlling the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold can include:

[0025] If the first temperature difference is less than the temperature difference threshold, the water temperature entering the battery is obtained, and a heating target water temperature corresponding to the heating mode is determined;

[0026] A third temperature difference between the water temperature entering the battery and the heating target water temperature is calculated.

[0027] The opening degree of the second flow control component is controlled according to the third temperature difference, wherein the opening degree of the second flow control component is positively correlated with the third temperature difference.

[0028] In a specific implementation of the first aspect, controlling the opening degree of the second flow control component according to the third temperature difference can include:

[0029] The opening degree of the second flow control component is controlled using a proportional integral control algorithm with the third temperature difference as an error amount.

[0030] In a specific implementation of the first aspect, controlling the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold can include:

[0031] If the first temperature difference is greater than or equal to the temperature difference threshold, the opening degree of the second flow control component is gradually reduced until the second flow control component is closed.

[0032] In a specific implementation of the first aspect, the battery temperature control method can further include:

[0033] If the electric drive of the vehicle is in the heat dissipation mode and the battery of the vehicle is in the heating mode, the heat of the electric drive is used to heat the battery.

[0034] A second aspect of the embodiments of the present application provides a battery temperature control device, which can include:

[0035] A passenger compartment information acquisition module is configured to obtain a current control temperature of a passenger compartment of a vehicle and a target control temperature of the passenger compartment.

[0036] A first temperature difference calculation module is configured to calculate a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment.

[0037] A battery temperature control module is configured to control a battery temperature of the vehicle according to the first temperature difference.

[0038] In a specific implementation of the second aspect, the battery temperature control module can include:

[0039] A temperature difference threshold determination sub-module is configured to determine a temperature difference threshold corresponding to a battery temperature control mode.

[0040] A battery temperature control sub-module is configured to control the battery temperature of the vehicle according to the first temperature difference and the temperature difference threshold.

[0041] In a specific implementation manner of the second aspect, the battery temperature control mode is the cooling mode; and the battery temperature control submodule can include:

[0042] The expansion valve control unit is configured to control the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold; and the first flow control component is configured to control the flow of the refrigerant for cooling the battery.

[0043] In a specific implementation manner of the second aspect, the expansion valve control unit can include:

[0044] The cooling target water temperature determination subunit is configured to, if the first temperature difference is less than the temperature difference threshold, obtain the battery inlet water temperature, and determine a cooling target water temperature corresponding to the cooling mode.

[0045] The second temperature difference calculation subunit is configured to calculate a second temperature difference between the battery inlet water temperature and the cooling target water temperature.

[0046] The expansion valve first control subunit is configured to control the opening degree of the first flow control component according to the second temperature difference; and the opening degree of the first flow control component is positively correlated with the second temperature difference.

[0047] In a specific implementation manner of the second aspect, the expansion valve opening degree control subunit can be specifically configured to use a proportional-integral control algorithm to control the opening degree of the first flow control component by taking the second temperature difference as an error amount.

[0048] In a specific implementation manner of the second aspect, the expansion valve control unit can further include:

[0049] The expansion valve second control subunit is configured to, if the first temperature difference is greater than or equal to the temperature difference threshold, gradually reduce the opening degree of the first flow control component until the opening degree is reduced to a minimum opening degree corresponding to the cooling mode.

[0050] In a specific implementation manner of the second aspect, the battery temperature control mode is the heating mode; and the battery temperature control submodule can include:

[0051] The three-way valve control unit is configured to control the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold; and the second flow control component is configured to control the flow of the coolant for heating the battery.

[0052] In a specific implementation manner of the second aspect, the three-way valve control unit can include:

[0053] The heating target water temperature determination subunit is configured to, if the first temperature difference is less than the temperature difference threshold, obtain the battery inlet water temperature, and determine a heating target water temperature corresponding to the heating mode.

[0054] a third temperature difference calculation subunit configured to calculate a third temperature difference between the water temperature entering the battery and the heating target water temperature;

[0055] a three-way valve first control subunit configured to control the opening degree of the second flow control component according to the third temperature difference, wherein the opening degree of the second flow control component is positively correlated with the third temperature difference.

[0056] In an implementation form of the second aspect, the three-way valve opening degree control subunit can be specifically configured to use a proportional integral control algorithm to control the opening degree of the second flow control component with the third temperature difference as an error amount.

[0057] In an implementation form of the second aspect, the three-way valve control unit can further include:

[0058] a three-way valve second control subunit configured to gradually reduce the opening degree of the second flow control component until the second flow control component is closed if the first temperature difference is greater than or equal to the temperature difference threshold.

[0059] In an implementation form of the second aspect, the battery temperature control device can further include:

[0060] an electric drive heating module configured to use heat of an electric drive to heat the battery if the electric drive of the vehicle is in a heat dissipation mode and the battery of the vehicle is in a heating mode.

[0061] A third aspect of the embodiments of the present application provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the steps of any of the battery temperature control methods.

[0062] A fourth aspect of the embodiments of the present application provides a battery management system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor implements the steps of any of the battery temperature control methods when executing the computer program.

[0063] A fifth aspect of the embodiments of the present application provides a computer program product, which, when executed on a battery management system, causes the battery management system to perform the steps of any of the battery temperature control methods.

[0064] The beneficial effects of the embodiments of the present application compared with the prior art are that the embodiments of the present application obtain the current control temperature of the passenger compartment of the vehicle and the target control temperature of the passenger compartment; calculate a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment; and control the battery temperature of the vehicle according to the first temperature difference. Through the embodiments of the present application, instead of only focusing on the battery itself, the temperature control of the battery and the temperature control of the passenger compartment are regarded as an organic whole, avoiding the adverse effect on the passenger compartment temperature control effect caused by one-sided pursuit of the best battery temperature control effect, and effectively improving the use experience of the passengers. BRIEF DESCRIPTION OF DRAWINGS

[0065] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0066] Figure 1 An embodiment schematic diagram of a battery temperature control system in the embodiments of the present application;

[0067] Figure 2 An embodiment flow chart of a battery temperature control method in the embodiments of the present application;

[0068] Figure 3 A schematic diagram of the flow direction of the refrigerant circuit and the cooling liquid circuit when the battery is in the refrigeration mode;

[0069] Figure 4 A schematic flow chart of controlling the opening degree of the first flow control component;

[0070] Figure 5 A schematic diagram of the flow direction of the cooling liquid circuit when the battery is in the heating mode and the electric drive does not need to be cooled;

[0071] Figure 6 A schematic flow chart of controlling the opening degree of the second flow control component;

[0072] Figure 7 A schematic diagram of the flow direction of the cooling liquid circuit when the battery is in the heating mode and the electric drive is in the cooling mode;

[0073] Figure 8 An embodiment structure diagram of a battery temperature control device in the embodiments of the present application;

[0074] Figure 9 A schematic block diagram of a battery management system in the embodiments of the present application. DETAILED DESCRIPTION

[0075] In order to make the objectives, characteristics, advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0076] It should be understood that when used in the specification and the appended claims, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0077] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clearly indicated by the context, the singular forms "a", "an" and "the" are intended to include the plural forms as well.

[0078] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0079] As used in the present application specification and the appended claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [a described condition or event] is detected" can be interpreted as meaning "upon determining" or "in response to determining" or "upon detecting [a described condition or event]" or "in response to detecting [a described condition or event]", depending on the context.

[0080] In addition, in the description of the present application, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0081] The embodiments of the present application provide a battery temperature control method, device, computer readable storage medium and battery management system, which are suitable for various scenarios of battery temperature control in actual use of the battery. For example, the specific application scenario of temperature control of the battery of an electric vehicle during driving or charging.

[0082] In order to better understand the embodiments of the present application, the battery temperature control method, device, computer readable storage medium and battery management system provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0083] The execution subject of the battery temperature control method provided by the embodiments of the present application can be a battery management system of an electric vehicle. The battery management system can regard the temperature control of the battery and the temperature control of the passenger compartment as an organic whole, thereby avoiding the adverse effect on the temperature control effect of the passenger compartment due to the one-sided pursuit of the optimal battery temperature control effect, and effectively improving the use experience of passengers.

[0084] For the convenience of description, the battery temperature control system shown in Figure 1 It should be noted that the battery temperature control system is only one possible example, and is not a limitation on the specific application environment of the battery temperature control method provided by the embodiments of the present application. The battery temperature control method provided by the embodiments of the present application can also be applied to other battery temperature control systems.

[0085] As shown in Figure 1 The battery temperature control system can include a refrigerant circuit and a cooling liquid circuit.

[0086] In the refrigerant circuit, the circulation of the refrigerant is powered by a compressor. The refrigerant discharged by the compressor is divided into two paths. One path flows through an evaporator for refrigeration of the passenger compartment, and the other path flows through a battery cooling module for refrigeration of the battery.

[0087] Before flowing through the evaporator, the refrigerant flowing through the evaporator can be controlled by an electronic expansion valve (EXV) connected to the evaporator. In order to distinguish, the EXV is referred to as an evaporator-side EXV. The opening degree of the evaporator-side EXV is positively correlated with the refrigerant flow rate flowing through the evaporator. That is, the greater the opening degree of the evaporator-side EXV, the greater the refrigerant flow rate flowing through the evaporator, and the better the refrigeration effect of the passenger compartment. Conversely, the smaller the opening degree of the evaporator-side EXV, the smaller the refrigerant flow rate flowing through the evaporator, and the worse the refrigeration effect of the passenger compartment.

[0088] Similarly, the refrigerant can be controlled by an EXV connected with the battery cooling module before flowing into the battery cooling module, for the convenience of distinction, the EXV is referred to as a battery-side EXV, the opening degree of the battery-side EXV is positively correlated with the refrigerant flow into the battery cooling module, that is, the greater the opening degree of the battery-side EXV, the greater the refrigerant flow into the battery cooling module, the better the refrigeration effect of the battery, on the contrary, the smaller the opening degree of the battery-side EXV, the smaller the refrigerant flow into the battery cooling module, the worse the refrigeration effect of the battery.

[0089] In the cooling liquid circuit, the circulation of the cooling liquid is powered by water pumps, the specific number and position of the water pumps can be set according to the actual situation, and the embodiments of the present application do not make specific limitations. In Figure 1 three water pumps are shown, for the convenience of distinction, the water pump in the same branch with the electric drive is referred to as water pump 1, the water pump in the same branch with the battery is referred to as water pump 2, and the water pump in the same branch with the heater core is referred to as water pump 3.

[0090] In the heating mode, if the electric drive needs to be cooled, the heat of the electric drive can be used to heat the battery, without starting the heater, thereby saving energy. At this time, water pump 1 and water pump 2 work, and water pump 3 does not work. Under the drive of water pump 1, the cooling liquid flowing through the electric drive is heated by the electric drive, and under the drive of water pump 2, the heated cooling liquid flowing through the battery heats the battery. When the electric drive dissipates more heat, the heated cooling liquid is divided into two paths by the three-way valve (i.e. Figure 1 three-way valve 1 in the heating mode), one path flows through the battery, and the other path flows through the condenser fan and is cooled by the condenser fan.

[0091] In the heating mode, if the electric drive does not need to be cooled, water pump 2 and water pump 3 work, and water pump 1 does not work. The cooling liquid flowing through the heater is heated by the heater, wherein the heater can be a positive temperature coefficient (PTC) heater or other types of heaters. The heated cooling liquid flows into the three-way valve (i.e. Figure 1The three-way valve 2) in the battery cooling module 1) is driven by the water pump 2) and divides the cooling liquid into two paths by the three-way valve, one path flows through the battery from an outlet of the three-way valve driven by the water pump 2) for heating the battery, for the sake of distinction, the outlet is recorded as the battery-side three-way valve outlet, the opening degree of the battery-side three-way valve outlet is positively correlated with the flow rate of the cooling liquid flowing through the battery, that is, the greater the opening degree of the battery-side three-way valve outlet, the greater the flow rate of the cooling liquid flowing through the battery, the better the heating effect of the battery, on the contrary, the smaller the opening degree of the battery-side three-way valve outlet, the smaller the flow rate of the cooling liquid flowing through the battery, the worse the heating effect of the battery. The other path flows through the heater core from another outlet of the three-way valve driven by the water pump 3) for heating the passenger compartment, for the sake of distinction, the outlet is recorded as the heater core-side three-way valve outlet, the opening degree of the heater core-side three-way valve outlet is positively correlated with the flow rate of the cooling liquid flowing through the heater core, that is, the greater the opening degree of the heater core-side three-way valve outlet, the greater the flow rate of the cooling liquid flowing through the heater core, the better the heating effect of the passenger compartment, on the contrary, the smaller the opening degree of the heater core-side three-way valve outlet, the smaller the flow rate of the cooling liquid flowing through the heater core, the worse the heating effect of the passenger compartment.

[0092] In the refrigeration mode, only the water pump 2) works, and the water pump 1) and the water pump 3) do not work, under the drive of the water pump 2), the cooling liquid circulates in the loop composed of the battery cooling module and the battery. The cooling liquid is cooled by the battery cooling module when flowing through the battery cooling module, and the cooled cooling liquid takes away the heat of the battery when flowing through the battery, thereby achieving the battery refrigeration effect.

[0093] Please refer to Figure 2 An embodiment of the battery temperature control method in the application can include:

[0094] In step S201, the current control temperature of the passenger compartment of the vehicle and the target control temperature of the passenger compartment are obtained.

[0095] In a specific implementation manner of the embodiment of the application, the battery temperature control mode can be obtained first, that is, it is determined whether the battery is in the refrigeration mode or the heating mode.

[0096] When the battery is in the refrigeration mode, the current temperature of the evaporator can be taken as the current control temperature of the passenger compartment, and the target temperature of the evaporator can be taken as the target control temperature of the passenger compartment. The current temperature of the evaporator can be measured by a temperature sensor pre-set at the evaporator, and the target temperature of the evaporator can be a default value preset by the system or set freely by the user.

[0097] When the battery is in heating mode, the current temperature of the heater core can be used as the current control temperature of the passenger compartment, and the target temperature of the heater core can be used as the target control temperature of the passenger compartment. The current temperature of the heater core can be measured by a temperature sensor pre-set at the heater core, and the target temperature of the heater core can be a system default value or can be set by the user.

[0098] Step S202: Calculate the first temperature difference between the current controlled temperature of the passenger cabin and the target controlled temperature of the passenger cabin.

[0099] In simple terms, when the battery is in cooling mode, the first temperature difference is the difference between the current temperature of the evaporator and the target temperature of the evaporator. When the battery is in heating mode, the first temperature difference is the difference between the current temperature of the heater core and the target temperature of the heater core.

[0100] Step S203: Control the battery temperature of the vehicle based on the first temperature difference.

[0101] In one specific implementation of this application, a temperature difference threshold corresponding to the battery temperature control mode can be determined first, and the battery temperature of the vehicle can be controlled according to the first temperature difference and the temperature difference threshold.

[0102] Specifically, when the battery is in cooling mode, the flow directions of the refrigerant circuit and the coolant circuit are as follows: Figure 3 As shown in the solid line portion, in the refrigerant circuit, the refrigerant discharged from the compressor is divided into two paths: one flows through the evaporator for cooling the passenger compartment, and the other flows through the battery cooling module for cooling the battery. In the coolant circuit, driven by water pump 2, the coolant circulates in the circuit consisting of the battery cooling module and the battery. The coolant is cooled by the battery cooling module as it flows through it, and the cooled coolant carries away heat from the battery as it flows through it. In this case, the opening degree of the first flow control component can be controlled based on the first temperature difference and the temperature difference threshold, thereby achieving the effect of controlling the battery temperature. The first flow control component can be the battery-side EXV. The specific control process for the opening degree of the first flow control component is as follows: Figure 4 As shown:

[0103] Step S401: Determine whether the first temperature difference is less than the temperature difference threshold.

[0104] If the first temperature difference is less than the temperature difference threshold, then proceed to steps S402 to S404; if the first temperature difference is greater than or equal to the temperature difference threshold, then proceed to step S405.

[0105] Step S402: Obtain the water temperature of the battery and determine the target cooling water temperature corresponding to the cooling mode.

[0106] The battery water inlet temperature is the temperature of the cooling liquid flowing into the battery, which can be measured by a temperature sensor prearranged at the battery. The refrigeration target water temperature corresponding to the refrigeration mode can be a default value preset by the system or freely set by the user.

[0107] In step S403, a second temperature difference between the battery water inlet temperature and the refrigeration target water temperature is calculated.

[0108] The second temperature difference is the difference between the battery water inlet temperature and the refrigeration target water temperature.

[0109] In step S404, the opening degree of the first flow control component is controlled according to the second temperature difference.

[0110] The opening degree of the first flow control component is positively correlated with the second temperature difference, that is, the greater the second temperature difference, the greater the opening degree of the first flow control component, and vice versa.

[0111] In a specific implementation manner of the embodiments of the present application, the second temperature difference can be used as an error amount, and a proportional integral (PI) control algorithm can be used to control the opening degree of the first flow control component. The specific control manner is shown in the following formula: the opening degree of the first flow control component = estimated opening degree + second temperature difference x proportional coefficient + second temperature difference x integral coefficient + cumulative integral.

[0112] The specific values of the proportional coefficient and the integral coefficient can be set according to actual conditions, which are not limited in the embodiments of the present application. Preferably, the proportional coefficient can be positively correlated with the second temperature difference, that is, the greater the second temperature difference, the greater the proportional coefficient, and vice versa. Similarly, the integral coefficient can be positively correlated with the second temperature difference, that is, the greater the second temperature difference, the greater the integral coefficient, and vice versa.

[0113] For example, when the second temperature difference between the battery water inlet temperature and the refrigeration target water temperature is 20℃, the integral coefficient is selected as 10, the proportional coefficient is selected as 4, the estimated opening degree is 0, and the cumulative integral is 0, the opening degree of the first flow control component can be calculated as 280 steps. When the second temperature difference is reduced to 10℃, the integral coefficient is selected as 5, the proportional coefficient is selected as 2, the EXV estimated opening degree is 0, and the cumulative integral is 0, the opening degree of the first flow control component can be calculated as 70 steps.

[0114] In step S405, the opening degree of the first flow control component is gradually reduced until it is reduced to the minimum opening degree corresponding to the refrigeration mode.

[0115] In a specific implementation manner of the embodiment of the present application, the opening degree of the first flow control component can be gradually reduced at a preset control speed, and the specific value of the control speed can be set according to actual conditions, for example, the control speed can be set as 1 step / s or other values, and the embodiment of the present application does not make a specific limitation thereto. When the opening degree of the first flow control component is reduced to the minimum opening degree corresponding to the refrigeration mode, the minimum opening degree is maintained.

[0116] In a specific implementation manner of the embodiment of the present application, the refrigeration mode can also be subdivided into a plurality of different levels. The specific number of levels can be set according to actual conditions, and the embodiment of the present application does not make a specific limitation thereto.

[0117] For the convenience of description, the refrigeration mode is subdivided into a first-level refrigeration mode, a second-level refrigeration mode and a third-level refrigeration mode as an example for description. The first-level refrigeration mode, the second-level refrigeration mode and the third-level refrigeration mode have increasing requirements for the battery refrigeration degree in turn, that is, the first-level refrigeration mode has the lowest requirement for the battery refrigeration degree, and the third-level refrigeration mode has the highest requirement for the battery refrigeration degree.

[0118] When the battery is in the first-level refrigeration mode, the opening degree of the first flow control component can be controlled according to the process as shown in Figure 4 . It should be noted that the temperature difference threshold value at this time should be the temperature difference threshold value corresponding to the first-level refrigeration mode, the refrigeration target water temperature at this time should be the refrigeration target water temperature corresponding to the first-level refrigeration mode, and the minimum opening degree at this time should be the minimum opening degree corresponding to the first-level refrigeration mode.

[0119] When the battery is in the second-level refrigeration mode, the opening degree of the first flow control component can be controlled according to the process as shown in Figure 4 . It should be noted that the temperature difference threshold value at this time should be the temperature difference threshold value corresponding to the second-level refrigeration mode, the refrigeration target water temperature at this time should be the refrigeration target water temperature corresponding to the second-level refrigeration mode, and the minimum opening degree at this time should be the minimum opening degree corresponding to the second-level refrigeration mode. The temperature difference threshold value corresponding to the first-level refrigeration mode is greater than the temperature difference threshold value corresponding to the second-level refrigeration mode, the refrigeration target water temperature corresponding to the first-level refrigeration mode is greater than the refrigeration target water temperature corresponding to the second-level refrigeration mode, and the minimum opening degree corresponding to the first-level refrigeration mode is less than the minimum opening degree corresponding to the second-level refrigeration mode.

[0120] When the battery is in the third-level cooling mode, the cooling requirements are the highest, and all efforts must be made to cool the battery, without considering the passenger compartment. In this situation, the opening of the first flow control component can be controlled based on the superheat level on the battery side. Specifically, when the superheat level is greater than a preset superheat threshold, the opening of the first flow control component can be gradually increased at a preset control rate; conversely, when the superheat level is less than or equal to the preset superheat threshold, the opening of the first flow control component can be gradually decreased at a preset control rate.

[0121] When the battery does not require cooling, the first flow control component can be turned off, at which point the refrigerant will no longer flow through the battery cooling module. However, water pump 2 can continue to operate to ensure that the battery's highest and lowest temperatures do not differ too much (e.g., not equal to 5°C), thus achieving a uniform battery temperature.

[0122] When the battery is in heating mode, if the electric drive does not require heat dissipation, the flow direction of the coolant circuit is as follows: Figure 5 As shown in the solid line, the coolant is heated by the heater as it flows through it. The heated coolant then flows into the three-way valve 2, which divides it into two paths. One path, driven by the water pump 2, flows through the battery-side three-way valve outlet to the battery for heating. The other path, driven by the water pump 3, flows through the heater core-side three-way valve outlet to the heater core for heating the passenger compartment. In this configuration, the opening of the second flow control component can be controlled based on the first temperature difference and a temperature difference threshold, thereby controlling the battery temperature. The second flow control component can be the battery-side three-way valve outlet. The specific control process for the opening of the second flow control component is as follows: Figure 6 As shown:

[0123] Step S601: Determine whether the first temperature difference is less than the temperature difference threshold.

[0124] If the first temperature difference is less than the temperature difference threshold, then proceed to steps S602 to S604; if the first temperature difference is greater than or equal to the temperature difference threshold, then proceed to step S605.

[0125] Step S602: Obtain the water temperature of the battery and determine the target water temperature corresponding to the heating mode.

[0126] The battery immersion water temperature is the temperature of the coolant flowing into the battery, which can be measured by a temperature sensor pre-set at the battery. The target heating water temperature corresponding to the heating mode can be a system default value or can be set freely by the user.

[0127] Step S603: Calculate the third temperature difference between the water temperature when the battery is immersed and the target water temperature.

[0128] The third temperature difference is a difference between the water temperature entering the battery and the target water temperature.

[0129] In step S604, the opening of the second flow control component is controlled according to the third temperature difference.

[0130] The opening of the second flow control component is positively correlated with the third temperature difference, that is, the greater the third temperature difference, the greater the opening of the second flow control component, and vice versa, the smaller the third temperature difference, the smaller the opening of the second flow control component.

[0131] In a specific implementation of the embodiment, the third temperature difference can be used as an error amount, and a PI control algorithm can be used to control the opening of the second flow control component. The specific control method is as follows: the opening of the second flow control component = estimated opening + third temperature difference × proportional coefficient + third temperature difference × integral coefficient + cumulative integral.

[0132] The specific values of the proportional coefficient and the integral coefficient can be set according to actual conditions, and the embodiment is not limited in this regard. Preferably, the proportional coefficient can be positively correlated with the third temperature difference, that is, the greater the third temperature difference, the greater the proportional coefficient, and vice versa, the smaller the third temperature difference, the smaller the proportional coefficient. Similarly, the integral coefficient can be positively correlated with the third temperature difference, that is, the greater the third temperature difference, the greater the integral coefficient, and vice versa, the smaller the third temperature difference, the smaller the integral coefficient.

[0133] In step S605, the opening of the second flow control component is gradually reduced until the second flow control component is closed.

[0134] In a specific implementation of the embodiment, the opening of the second flow control component can be gradually reduced at a preset control speed until the second flow control component is closed. The specific value of the control speed can be set according to actual conditions, for example, it can be set to 1 step / s or other values, and the embodiment is not limited in this regard.

[0135] When the battery is in the heating mode, if the electric drive is in the cooling mode, the heat of the electric drive can be used to heat the battery, at this time, the flow direction of the cooling liquid circuit is as shown by the solid line in FIG. 6, under the drive of the water pump 1, the cooling liquid is heated by the electric drive when flowing through the electric drive, and under the drive of the water pump 2, the heated cooling liquid heats the battery when flowing through the battery. In this case, the heater does not need to be started, and the effect of saving energy can be achieved. Figure 7

[0136] ​To sum up, the embodiment of the application obtains the current control temperature of the passenger compartment of the vehicle and the target control temperature of the passenger compartment, calculates a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment, and controls the battery temperature of the vehicle according to the first temperature difference. Through the embodiment of the application, instead of focusing on the battery itself, the temperature control of the battery and the temperature control of the passenger compartment are regarded as an organic whole, thereby avoiding the adverse effect on the temperature control effect of the passenger compartment caused by one-sided pursuit of the optimal battery temperature control effect, and effectively improving the use experience of the passengers.

[0137] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiment of the application.

[0138] A battery temperature control method corresponding to the above embodiment, Figure 8 An embodiment structure diagram of a battery temperature control device provided by the embodiment of the application is shown.

[0139] In the embodiment, a battery temperature control device can include:

[0140] The passenger compartment information acquisition module 801 is configured to obtain the current control temperature of the passenger compartment of the vehicle and the target control temperature of the passenger compartment.

[0141] The first temperature difference calculation module 802 is configured to calculate a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment.

[0142] The battery temperature control module 803 is configured to control the battery temperature of the vehicle according to the first temperature difference.

[0143] In a specific implementation manner of the embodiment of the application, the battery temperature control module can include:

[0144] The temperature difference threshold determination sub-module is configured to determine a temperature difference threshold corresponding to the battery temperature control mode.

[0145] The battery temperature control sub-module is configured to control the battery temperature of the vehicle according to the first temperature difference and the temperature difference threshold.

[0146] In a specific implementation manner of the embodiment of the application, the battery temperature control mode is a refrigeration mode; and the battery temperature control sub-module can include:

[0147] The expansion valve control unit is configured to control the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold; and the first flow control component is configured to control the flow of the refrigerant for refrigerating the battery.

[0148] In a specific implementation manner of the embodiment of the present application, the expansion valve control unit can comprise:

[0149] The refrigeration target water temperature determination subunit is configured to: if the first temperature difference is less than the temperature difference threshold, acquire the battery inlet water temperature, and determine a refrigeration target water temperature corresponding to the refrigeration mode.

[0150] The second temperature difference calculation subunit is configured to calculate a second temperature difference between the battery inlet water temperature and the refrigeration target water temperature.

[0151] The expansion valve first control subunit is configured to control the opening degree of the first flow control component according to the second temperature difference, wherein the opening degree of the first flow control component is positively correlated with the second temperature difference.

[0152] In a specific implementation manner of the embodiment of the present application, the expansion valve opening degree control subunit can be specifically configured to: use a proportional integral control algorithm to control the opening degree of the first flow control component by taking the second temperature difference as an error amount.

[0153] In a specific implementation manner of the embodiment of the present application, the expansion valve control unit can further comprise:

[0154] The expansion valve second control subunit is configured to: if the first temperature difference is greater than or equal to the temperature difference threshold, gradually reduce the opening degree of the first flow control component until the opening degree is reduced to a minimum opening degree corresponding to the refrigeration mode.

[0155] In a specific implementation manner of the embodiment of the present application, the battery temperature control mode is a heating mode; and the battery temperature control sub-module can comprise:

[0156] The three-way valve control unit is configured to control the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold, wherein the second flow control component is configured to control the flow of the cooling liquid for heating the battery.

[0157] In a specific implementation manner of the embodiment of the present application, the three-way valve control unit can comprise:

[0158] The heating target water temperature determination subunit is configured to: if the first temperature difference is less than the temperature difference threshold, acquire the battery inlet water temperature, and determine a heating target water temperature corresponding to the heating mode.

[0159] The third temperature difference calculation subunit is configured to calculate a third temperature difference between the battery inlet water temperature and the heating target water temperature.

[0160] The three-way valve first control subunit is configured to control the opening degree of the second flow control component according to the third temperature difference, wherein the opening degree of the second flow control component is positively correlated with the third temperature difference.

[0161] In a specific implementation manner of the embodiment of the present application, the three-way valve opening degree control subunit can be specifically configured to use a proportional integral control algorithm to control the opening degree of the second flow control component with the third temperature difference as an error amount.

[0162] In a specific implementation manner of the embodiment of the present application, the three-way valve control unit can further include:

[0163] The three-way valve second control subunit is configured to gradually reduce the opening degree of the second flow control component until the second flow control component is closed if the first temperature difference is greater than or equal to the temperature difference threshold.

[0164] In a specific implementation manner of the embodiment of the present application, the battery temperature control apparatus can further include:

[0165] The electric drive heating module is configured to use heat of the electric drive to heat the battery if the electric drive of the vehicle is in a heat dissipation mode and the battery of the vehicle is in a heating mode.

[0166] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the apparatuses, modules and units described above can refer to the corresponding processes in the foregoing method embodiments, which will not be described herein.

[0167] In the foregoing embodiments, the description of each embodiment has its own focus, and the parts not described or recorded in detail in a certain embodiment can refer to the relevant description of other embodiments.

[0168] Figure 9 A schematic block diagram of a battery management system provided by an embodiment of the present application is shown, and only parts related to the embodiments of the present application are shown for the convenience of description.

[0169] As shown in Figure 9 The battery management system 9 of this embodiment includes a processor 90, a memory 91, and a computer program 92 stored in the memory 91 and executable on the processor 90. The processor 90 implements the steps in each of the battery temperature control method embodiments described above when executing the computer program 92, such as Figure 2 Steps S201 to S203 shown. Alternatively, the processor 90 implements the functions of each module / unit in the foregoing apparatus embodiments when executing the computer program 92, such as Figure 8 The functions of the modules 801 to 803 shown.

[0170] For example, the computer program 92 can be divided into one or more modules / units, one or more modules / units are stored in the memory 91 and executed by the processor 90 to complete the present application. One or more modules / units can be a series of computer program instruction segments capable of completing a specific function, which are used to describe the execution process of the computer program 92 in the battery management system 9.

[0171] Those skilled in the art can understand that, Figure 9 The battery management system 9 is only an example and does not constitute a limitation on the battery management system 9, and can include more or fewer components than illustrated, or combine certain components, or different components, for example, the battery management system 9 can also include input / output devices, network access devices, buses, etc.

[0172] The processor 90 can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0173] The memory 91 can be an internal storage unit of the battery management system 9, such as a hard disk or a memory of the battery management system 9. The memory 91 can also be an external storage device of the battery management system 9, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 91 can include both the internal storage unit and the external storage device of the battery management system 9. The memory 91 is used to store computer programs and other programs and data required by the battery management system 9. The memory 91 can also be used to temporarily store data that has been output or will be output.

[0174] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be realized in the form of hardware or software function unit. In addition, the specific name of each functional unit and module is only for the convenience of mutual distinction, and does not limit the protection scope of the present application. The specific working process of the unit and module in the above system can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

[0175] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0176] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0177] In the embodiments provided in the present application, it should be understood that the disclosed device / battery management system and method can be implemented in other ways. For example, the device / battery management system embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0178] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or they can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0179] In addition, each of the function units in each of the embodiments of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software function unit.

[0180] If the integrated module / unit is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. When the processor executes the computer program, the steps of each method embodiment described above can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer readable storage medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer readable storage medium does not include electrical carrier signals and telecommunication signals.

[0181] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A battery temperature control method characterized by, The method comprises the following steps: obtaining a current control temperature of a passenger compartment of a vehicle and a target control temperature of the passenger compartment; calculating a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment; determining a temperature difference threshold corresponding to a battery temperature control mode; if the first temperature difference is less than the temperature difference threshold, obtaining a battery inlet water temperature; when the battery is in a refrigeration mode, determining a refrigeration target water temperature corresponding to the refrigeration mode; calculating a second temperature difference between the battery inlet water temperature and the refrigeration target water temperature; controlling an opening degree of a first flow control component according to the second temperature difference, wherein the first flow control component is used to control the flow of refrigerant for battery refrigeration, and the opening degree of the first flow control component is positively correlated with the second temperature difference; when the battery is in a heating mode, determining a heating target water temperature corresponding to the heating mode; calculating a third temperature difference between the battery inlet water temperature and the heating target water temperature; and controlling an opening degree of a second flow control component according to the third temperature difference, wherein the second flow control component is used to control the flow of coolant for battery heating, and the opening degree of the second flow control component is positively correlated with the third temperature difference.

2. The battery temperature control method according to claim 1, characterized by, The control of the opening degree of the first flow control component according to the second temperature difference comprises: using a proportional-integral control algorithm to control the opening degree of the first flow control component with the second temperature difference as an error amount.

3. The battery temperature control method according to claim 1, characterized by, The control of the opening degree of the first flow control component according to the first temperature difference and the temperature difference threshold comprises: if the first temperature difference is greater than or equal to the temperature difference threshold, gradually reducing the opening degree of the first flow control component until it is reduced to a minimum opening degree corresponding to the refrigeration mode.

4. The battery temperature control method according to claim 1, characterized by, The control of the opening degree of the second flow control component according to the third temperature difference comprises: using a proportional-integral control algorithm to control the opening degree of the second flow control component with the third temperature difference as an error amount.

5. The battery temperature control method according to claim 1, characterized by, The control of the opening degree of the second flow control component according to the first temperature difference and the temperature difference threshold comprises: if the first temperature difference is greater than or equal to the temperature difference threshold, gradually reducing the opening degree of the second flow control component until the second flow control component is closed.

6. The battery temperature control method according to claim 1, wherein The method further comprises: if the electric drive of the vehicle is in a heat dissipation mode and the battery of the vehicle is in a heating mode, using the heat of the electric drive to heat the battery.

7. A battery temperature control device characterized by comprising: The method comprises the following steps: a passenger compartment information acquisition module is configured to obtain a current control temperature of a passenger compartment of a vehicle and a target control temperature of the passenger compartment; a first temperature difference calculation module is configured to calculate a first temperature difference between the current control temperature of the passenger compartment and the target control temperature of the passenger compartment; a battery temperature control module is configured to determine a temperature difference threshold corresponding to a battery temperature control mode; and if the first temperature difference is less than the temperature difference threshold, obtain a battery inlet water temperature; when the battery is in a refrigeration mode, determine a refrigeration target water temperature corresponding to the refrigeration mode; calculate a second temperature difference between the battery inlet water temperature and the refrigeration target water temperature; According to the second temperature difference, the opening of a first flow control component is controlled, wherein the first flow control component is used for controlling the flow of refrigerant for battery refrigeration, and the opening of the first flow control component is positively correlated with the second temperature difference; when the battery is in a heating mode, a heating target water temperature corresponding to the heating mode is determined; a third temperature difference between the battery inlet water temperature and the heating target water temperature is calculated; and according to the third temperature difference, the opening of a second flow control component is controlled, wherein the second flow control component is used for controlling the flow of cooling liquid for battery heating, and the opening of the second flow control component is positively correlated with the third temperature difference.

8. A computer-readable storage medium storing a computer program, the computer-readable storage medium comprising: The computer program, when executed by a processor, implements the steps of the battery temperature control method according to any one of claims 1 to 6.

9. A battery management system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor, when executing the computer program, implements the steps of the battery temperature control method according to any one of claims 1 to 6.

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