BMS thermal management function test bench and test method

Abstract

The invention relates to an embedded system test method, and discloses a test bench and a test system for a BMS thermal management function, the test bench is used for testing a BMS controller, the test bench can comprise an upper computer and a lower computer, and the lower computer can comprise a communication board card and a digital rheostat. The upper computer is used for operating simulation software, and the simulation software can send a control signal. The lower computer is in communication connection with the upper computer through the communication board card, the communication board card is connected with the digital rheostat, the communication board card and the digital rheostat are respectively connected with the BMS controller, the digital rheostat is used for changing resistance values according to control signals of simulation software, and the resistance values of the digital rheostat are in one-to-one correspondence with temperatures. The test method comprises the following steps: sending a driving signal to a BMS controller through simulation software; assigning the resistance value of the digital rheostat as a target resistance value; sending the target resistance value to a BMS controller; acquiring a thermal management state signal fed back by the BMS controller; and judging whether the BMS thermal management function of the BMS controller is normal or not according to the thermal management state signal.

Description

Technical Field

[0001] The present application relates to an embedded system testing method, and in particular to a BMS thermal management function testing method. Background Art

[0002] At present, power batteries face various complex working conditions in actual use. During the driving process of electric vehicles, the charge and discharge status of the battery will change with factors such as driving behavior (such as sudden acceleration, sudden braking, and long-term constant speed driving), road conditions (such as congested roads in cities, highways), and environmental conditions (such as high temperature weather and low temperature environment). These complex and changeable working conditions will cause complex changes in battery temperature, which is crucial for the management and control of battery temperature. Therefore, a large number of tests are required on the BMS (Battery Management System) controller.

[0003] During the R&D and experimental stages, some extreme conditions are difficult to reproduce, and even if they are reproduced, higher testing costs are required. Since the temperature needs to be simulated to increase and decrease, the temperature change requires more energy transfer to achieve, so a longer testing time is required.

[0004] Therefore, a testing method is needed that can save testing time and facilitate simulation of extreme temperature environments. Summary of the invention

[0005] The technical problem to be solved by this application is that BMS testing of electric vehicles takes a long time and extreme environments are difficult to reproduce.

[0006] In order to solve the above technical problems, the present application provides a test bench and a test method for the thermal management function of a BMS.

[0007] In a first aspect of the present application, a test bench for a BMS thermal management function is provided, the test bench being used to test a BMS controller, the test bench comprising: a host computer, the host computer being used to run simulation software, the simulation software being able to send control signals; a lower computer, the lower computer comprising a communication board and a digital rheostat, the lower computer being communicatively connected to the host computer via the communication board, the communication board being connected to the digital rheostat, the communication board and the digital rheostat being respectively connected to the BMS controller, the digital rheostat being used to change resistance according to the control signal of the simulation software, the resistance value of the digital rheostat corresponding one-to-one to the temperature.

[0008] In one embodiment, the test bench includes a plurality of digital rheostats, and the temperatures corresponding to the digital rheostats include a plurality of battery temperatures, a water inlet temperature, and a water outlet temperature.

[0009] In one embodiment, the test bench further includes a connection platform, which includes a plurality of interfaces, and the interfaces are used to transfer connection lines between a plurality of components of the lower computer and the BMS controller.

[0010] In one embodiment, the communication board is a CAN calibration analyzer, and the control signal is a VCU message.

[0011] According to a second aspect of the present application, a method for testing a BMS thermal management function is provided. The method is applied to the test bench provided in the first aspect of the present application. The method comprises: sending a driving signal to a BMS controller through simulation software, the driving signal being used to indicate a current vehicle operating condition simulated by the simulation software, the current vehicle operating condition being one of several vehicle operating conditions; specifying a resistance value of a digital variable resistor as a target resistance value, the target resistance value corresponding to a target temperature; sending the target resistance value to the BMS controller; obtaining a thermal management status signal fed back by the BMS controller; and determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management status signal.

[0012] In one embodiment, specifying the resistance value of the digital rheostat as the target resistance value includes: changing the resistance values ​​of several digital rheostats to correspond to changing several target battery temperatures, target water inlet temperatures and target water outlet temperatures; the thermal management status signal includes: the BMS controller obtains the changed target battery pack temperature difference according to the several target battery temperatures, obtains the target inlet and outlet temperature difference according to the target water inlet temperature and the target water outlet temperature, and generates an inlet temperature demand signal and a cooling water pump duty cycle demand signal according to the target battery pack temperature difference and the target inlet and outlet temperature difference; determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management status signal includes: determining whether the difference between the water inlet temperature demand signal and the cooling water pump duty cycle demand signal and their respective standard demand signals is within an error range; if it is determined that the difference is within the error range, then determining that the BMS thermal management function of the BMS controller is normal; otherwise, determining that the BMS thermal management function of the BMS controller is abnormal.

[0013] In one embodiment, the thermal management status signal further includes a signal indicating that the battery pack is operating restricted, and the testing method further includes:

[0014] Enable the BMS controller to obtain the current temperature and thermal management status of the simulated battery pack, the thermal management status is used to indicate that the battery pack is currently in a state of changing or maintaining the water inlet temperature; change the resistance value of the digital rheostat to correspond to the change in the target water inlet temperature, so that the changing trend of the water inlet temperature is opposite to the trend of the current thermal management state changing the water inlet temperature; determine whether a signal indicating that the battery pack is restricted in operation can be parsed from the thermal management status signal; if a signal indicating that the battery pack is restricted in operation can be parsed from the thermal management status signal, then it is determined that the thermal management fault handling function of the BMS controller is normal; if a signal indicating that the battery pack is restricted in operation cannot be parsed from the thermal management status signal, then it is determined that the thermal management fault handling function of the BMS controller is abnormal.

[0015] In one embodiment, the target temperature is the lowest temperature of the battery pack. Under the current vehicle operating condition, the lowest temperature of the battery pack corresponds to a unique target thermal management state. Before determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller, the testing method also includes: determining whether the BMS thermal management function of the BMS controller is valid; if the thermal management state signal fed back by the BMS controller is obtained, reading the current thermal management state from the thermal management state signal; judging whether the current thermal management state is consistent with the target thermal management state; if the current thermal management state is consistent with the target thermal management state, determining that the BMS thermal management function of the BMS controller is valid, and continuing to execute the step of determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller; otherwise, determining that the BMS thermal management function of the BMS controller is invalid; if the thermal management state signal fed back by the BMS controller is not obtained, determining that the BMS thermal management function of the BMS controller is invalid.

[0016] In one embodiment, the vehicle operating condition includes a driving condition and a charging condition; when the current vehicle operating condition is a driving condition, if the lowest temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is a driving heating state; if the lowest temperature of the battery pack is lower than between 0 degrees Celsius and 35 degrees Celsius, the target thermal management state is a driving non-thermal management state; if the lowest temperature of the battery pack is higher than 35 degrees Celsius, the target thermal management state is a driving cooling state; when the current vehicle operating condition is a charging condition, if the lowest temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is a charging heating state; if the lowest temperature of the battery pack is lower than between 0 degrees Celsius and 45 degrees Celsius, the target thermal management state is a charging non-thermal management state; if the lowest temperature of the battery pack is higher than 45 degrees Celsius, the target thermal management state is a charging cooling state.

[0017] In one embodiment, sending a driving signal to the BMS controller through the simulation software includes: generating a VCU message through the simulation software, and sending the VCU message to the BMS controller by a CAN calibration analyzer.

[0018] Compared with the prior art, the test bench and test method for the thermal management function of a BMS in the embodiment of the present application have the following beneficial effects:

[0019] In the embodiment of the present application, by replacing the temperature-sensitive resistor with a digital rheostat, the resistance value of the digital rheostat can be directly specified according to the corresponding relationship between the resistance value and the temperature (that is, the relationship curve between the resistance value and the temperature), so as to instantly simulate the extreme temperature environment, save the test time, and do not require the real environment of the whole vehicle except the BMS controller, thus saving the test cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the framework of a test bench for BMS thermal management function exemplarily shown in one embodiment of the present application.

[0021] Figure 2 It is a flowchart of a method for testing a thermal management function of a BMS, exemplarily shown in an embodiment of the present application.

[0022] Figure 3 It is a flowchart of another method for testing the thermal management function of a BMS, exemplarily shown in an embodiment of the present application.

[0023] Figure 4 It is a flowchart of another method for testing the thermal management function of a BMS exemplarily shown in an embodiment of the present application.

[0024] Figure 5 It is a flowchart of another method for testing the thermal management function of a BMS exemplarily shown in an embodiment of the present application.

[0025] In the figure, 10, test bench, 101, host computer, 1011, simulation software, 102, slave computer, 1021, communication board, 1022, digital rheostat, 20, BMS controller. DETAILED DESCRIPTION

[0026] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0027] In the description of this application, it should be understood that the term target value used in this application refers to the expected value of a parameter for simulation software or BMS controller, such as the expected value for a specific parameter (such as the target thermal management state), or the expected parameter value for a component (such as the target resistance value). The meaning of the target value should be understood in conjunction with the execution subject of the current statement. In the actual production plan, the nouns in this application may be presented with other names, which should fall within the scope of protection of this application without hindering the implementation plan.

[0028] BMS (Battery Management System) is used for battery status estimation, battery balancing and battery safety management. When the battery is overcharged, over-discharged, over-heated or in other abnormal conditions, it can take protective measures in time, such as cutting off the circuit, to avoid battery combustion, explosion and other safety accidents.

[0029] The BMS controller is the brain of the battery management system, so testing the BMS controller can ensure that it can accurately monitor the battery status under various complex working conditions. For example, in a high temperature environment, the BMS can effectively prevent the battery from overheating; in a low temperature environment, it can also accurately estimate the battery's SOC. Through rigorous testing, the risk of safety accidents caused by poor battery management, such as battery fires or explosions, can be reduced, which is crucial to the safety of vehicles and the lives of drivers and passengers.

[0030] The inventors found that under existing test conditions, in order to obtain test data at high and low temperatures, the complete battery pack or even the entire vehicle needs to be placed in the laboratory for heating or cooling. The heating and cooling of the environment is relatively slow, and the time spent in the heating and cooling processes is non-value-added time. The energy consumed in heating and cooling also leads to high test costs.

[0031] Based on this, Figure 1 As shown, an embodiment of the present application shows a test bench 10 for a BMS thermal management function. The test bench 10 is used to test a BMS controller 20. The test bench 10 may include: a host computer 101 and a slave computer 102. The slave computer 102 may include a communication board 1021 and a digital rheostat 1022.

[0032] The host computer 101 is used to run the simulation software 1011, and the simulation software 1011 can send control signals. The lower computer 102 is connected to the host computer 101 through the communication board 1021, and the communication board 1021 is connected to the digital rheostat 1022, and the communication board 1021 and the digital rheostat 1022 are respectively connected to the BMS controller 20, and the digital rheostat 1022 is used to change the resistance value according to the control signal of the simulation software 1011, and the resistance value of the digital rheostat 1022 corresponds to the temperature one by one.

[0033] Through the above scheme, a digital rheostat 1022 is installed in the test bench 10, and the resistance value of the digital rheostat 1022 is controlled by the simulation software 1011. Since the digital rheostat 1022 is connected to the BMS controller 20, the digital rheostat 1022 can be sent to the BMS controller 20, so the digital rheostat 1022 can replace the traditional thermistor.

[0034] A real battery pack equipped with a thermistor needs to be placed in a real environment to feedback a specific temperature, while the digital rheostat 1022, under the control of the simulation software 1011, can almost instantly display the specified resistance value, thus saving the time of heating or cooling the real environment, and also saving the energy of heating and cooling, reducing the test cost.

[0035] When the battery pack to be tested is large, it may have multiple temperature sensors. To this end, in one embodiment, the test bench may include a plurality of digital rheostats, and the temperatures corresponding to the digital rheostats include a plurality of battery temperatures, water inlet temperatures, and water outlet temperatures.

[0036] It is understandable that the number of digital rheostats can be adjusted according to actual test conditions. For example, if the battery pack contains 300 single cells, 300 digital rheostats can be set to simulate the temperature of the single cells, and 2 digital rheostats can be set to simulate the temperature of the water inlet and the temperature of the water outlet.

[0037] In another embodiment, the digital rheostat can also output multiple simulated resistance values. For example, the exemplary battery pack contains 300 single cells, and 30 digital rheostats are provided, each of which is used to simulate the temperature of 10 single cells.

[0038] In addition, since the requirements for various temperature parameters are not performed simultaneously, under the control of the simulation software, the same digital rheostat can be used to simulate the temperature of different components at different times.

[0039] The above-mentioned arrangements of the various digital resistors can be used in combination to meet various testing requirements of BMS controllers.

[0040] Due to different vehicle models and vehicle configurations, the structure of the battery pack to be tested may be different, and therefore the BMS controller to be tested may also be different.

[0041] In order to improve the adaptability to different BMS controllers, in one embodiment, the test bench also includes a connection platform, which includes several interfaces for connecting the connection lines between several components of the lower computer and the BMS controller. Different BMS controllers are connected through the connection platform to achieve the adaptation of the test bench to different BMS controllers. Different objects to be tested do not need to change the test bench, so as to further reduce the test cost.

[0042] It is understandable that the interface on the connection platform can adopt a detachable structure that is easy to connect and disconnect, so as to increase the speed of test assembly and disassembly and save test time.

[0043] In the present application, the communication board is any one of an Ethernet communication board, an RS-232 communication board, an RS-485 communication board, a CAN communication board or a CAN calibration analyzer.

[0044] In one embodiment, in order to facilitate debugging of the BMS controller after testing, the communication board can be a CAN calibration analyzer, and the control signal is a VCU message, where CAN (Controller Area Network) and VCU (Vehicle Control Unit) are the two symbols.

[0045] The CAN calibration analyzer has a special data calibration function. It can send specific calibration commands to the target device and modify the internal parameters of the device. Therefore, through the above solution, the use of the CAN calibration analyzer can not only achieve the test purpose, but also modify the internal parameters of the BMS controller according to the test results after the test, so as to quickly carry out the next round of verification.

[0046] Correspondingly, such as Figure 2 As shown, the present application also provides a method for testing the thermal management function of a BMS. The testing method is applied to a test bench in any embodiment of the present application. The testing method may include:

[0047] S101, sending a driving signal to a BMS controller through simulation software, where the driving signal is used to indicate a current vehicle operating condition simulated by the simulation software, where the current vehicle operating condition is one of several vehicle operating conditions;

[0048] S102, specifying the resistance value of the digital rheostat to be a target resistance value, where the target resistance value corresponds to a target temperature;

[0049] S103, sending the target resistance value to the BMS controller;

[0050] S104, obtaining a thermal management status signal fed back by a BMS controller;

[0051] S105 . Determine whether the BMS thermal management function of the BMS controller is normal according to the thermal management status signal.

[0052] Through the above scheme, after the simulation software sends the driving signal to the BMS controller, it can trigger the internal processing logic of the BMS controller, so that after sending the target resistance value to the BMS controller, the BMS controller can respond as needed. The response data is also the thermal management status signal. The thermal management status signal is then analyzed by the simulation software. Since the resistance value is the resistance value presented by the digital resistor, the temperature of various conditions can be achieved without setting the real environment.

[0053] It is understandable that in order to reproduce the actual use of the vehicle, the specified current vehicle operating condition is associated with the target temperature. Since the resistance value is related to the temperature, the specified current vehicle operating condition can be associated with the resistance value of the specified digital resistor. The correspondence between the vehicle operating condition and the temperature or the correspondence between the temperature and the resistance value can be stored in the host computer or specified or input by the tester at the beginning of the test. This application does not impose any specific restrictions on this.

[0054] If the correspondence between the vehicle operating condition and the temperature or the correspondence between the temperature and the resistance value is specified or input by the tester when starting the test, the test bench in the present application may also include input devices such as a keyboard, a mouse, a touch screen, a digital tablet, a scanner, and a microphone.

[0055] In one embodiment, the test bench may include a plurality of digital rheostats, and thus the target temperature may include a plurality of target battery temperatures, target water inlet temperatures, and target water outlet temperatures.

[0056] Based on this, Figure 3 As shown, S102, specifying the resistance of the digital rheostat as the target resistance may include: S1021, changing the resistance of several digital rheostats to correspondingly change several target battery temperatures, target water inlet temperatures, and target water outlet temperatures.

[0057] The thermal management status signal obtained in S104 may include: the BMS controller obtains a changed target battery pack temperature difference based on several target battery temperatures, obtains a target water inlet and outlet temperature difference based on the target water inlet temperature and the target water outlet temperature, and generates a water inlet temperature demand signal and a cooling water pump duty cycle demand signal based on the target battery pack temperature difference and the target water inlet and outlet temperature difference.

[0058] S105. Determining whether the BMS thermal management function of the BMS controller is normal based on the thermal management status signal may include: S1051. Determining whether the difference between the water inlet temperature demand signal and the cooling water pump duty cycle demand signal and their respective standard demand signals is within an error range; S1052. If it is determined that the difference is within the error range, determining that the BMS thermal management function of the BMS controller is normal; S1053. Otherwise, determining that the BMS thermal management function of the BMS controller is abnormal.

[0059] By obtaining the target battery pack temperature difference, target water inlet temperature, and target water outlet temperature difference obtained by the BMS controller based on several target battery temperatures, the thermal state of the battery system can be more comprehensively reflected. Compared with single parameter testing, this comprehensive consideration can reduce misjudgments caused by abnormal fluctuations in individual parameters and improve the accuracy of judging whether the BMS thermal management function is normal.

[0060] It can be understood that the "target inlet and outlet temperature difference" is also the temperature difference between the "target inlet temperature" and the "target outlet temperature". If the target inlet temperature is 10 degrees Celsius and the target outlet temperature is 35 degrees Celsius, the target inlet and outlet temperature difference is calculated by the BMS controller to be -25 degrees Celsius. The target inlet and outlet temperature difference can be directly represented by positive and negative values, or by a positive number, and marked as a positive or negative value by an additional parameter. If the target inlet and outlet temperature difference is directly represented by positive and negative values, a positive value can be used to indicate that the target inlet temperature is higher than the target outlet temperature, and a negative value can be used to indicate that the target inlet temperature is lower than the target outlet temperature. A positive value can also be used to indicate that the target inlet temperature is lower than the target outlet temperature, and a negative value can be used to indicate that the target inlet temperature is higher than the target outlet temperature, depending on the actual situation.

[0061] It is understood that in any embodiment of the present application, the temperature may be any one of Celsius (°C), Fahrenheit (°F) or Kelvin (K). The temperature value or temperature range specified in the embodiment can be converted according to the conversion relationship of different temperature measurement units. Therefore, no matter which temperature measurement unit is used, when the converted temperature value or temperature range meets the requirements of any embodiment of the scheme of the present application, the corresponding scheme also falls within the protection scope of the present application, and the temperature measurement unit is not used to limit the scheme of the present application.

[0062] In one embodiment, if Figure 4 As shown, the thermal management status signal may also include a signal that the battery pack is restricted from working. Accordingly, the test method may also include:

[0063] S201, enabling the BMS controller to obtain the current temperature and thermal management state of the simulated battery pack, where the thermal management state is used to indicate that the battery pack is currently in a state of changing or maintaining the water inlet temperature;

[0064] S202, changing the resistance value of the digital rheostat to change the target water inlet temperature accordingly, so that the changing trend of the water inlet temperature is opposite to the trend of the water inlet temperature changing in the current thermal management state;

[0065] S203, determining whether a signal of battery pack operation restriction can be parsed from the thermal management status signal;

[0066] S204: If a signal that the battery pack is restricted in operation is parsed from the thermal management status signal, it is determined that the thermal management fault processing function of the BMS controller is normal;

[0067] S205: If a signal indicating that the battery pack is operating in a restricted manner cannot be parsed from the thermal management status signal, it is determined that the thermal management fault handling function of the BMS controller is abnormal.

[0068] Through the above solution, the signal of battery pack working restriction is included in the category of thermal management status signal, which broadens the test scope. The test not only focuses on conventional temperature-related parameters and thermal management adjustment conditions, but also includes the possible working restriction of the battery pack under special working conditions, making the test of the thermal management function of the BMS controller more comprehensive and able to more deeply detect the performance of the BMS controller in dealing with complex and abnormal situations.

[0069] In S202, the target water inlet temperature is changed by changing the resistance of the digital rheostat, and the change trend of the water inlet temperature is opposite to the trend of the current thermal management state changing the water inlet temperature, which cleverly uses the reverse verification method. By deliberately creating a situation that is contrary to normal thermal management regulation, the BMS controller's ability to cope with interference and abnormal changes and whether the fault handling mechanism can be triggered in time can be tested, thereby more accurately detecting the thermal management fault handling function.

[0070] When it is determined that the thermal management fault handling function is abnormal, based on the operation of relevant parameters such as the water inlet temperature in the test steps and the observation of the signal analysis, it can be further analyzed whether the problem occurs in the simulation interference link, the signal transmission link or the fault handling logic link inside the BMS controller, which helps to accurately locate the root cause of the fault, provide a strong basis for subsequent optimization and improvement, and facilitate R&D personnel to improve and optimize the thermal management fault handling mechanism of the BMS controller in a targeted manner.

[0071] As an example, when the battery pack is in a thermal management controlled heating / cooling state, the current battery pack temperature is obtained; the inlet and outlet temperatures are controlled not to meet thermal management requirements; if in a heating state, the inlet and outlet temperatures are controlled to be lower than the battery pack temperature; if in a cooling state, the inlet and outlet temperatures are controlled to be higher than the battery pack temperature.

[0072] On this basis, in one embodiment, thermal runaway under extremely high temperature conditions can also be simulated; the current battery pack operating status and battery pack thermal management status are obtained; if the battery pack operating status is not restricted or the thermal management status is not sent as required, it is determined that the BMS thermal management fault handling function is abnormal; if the battery pack operating status is restricted and the thermal management status is sent as required, it is determined that the BMS thermal management fault handling function is normal.

[0073] In one embodiment, the target temperature is the lowest temperature of the battery pack. Under the current vehicle operating condition, the lowest temperature of the battery pack corresponds to a unique target thermal management state. Before S105, determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller, the test method further includes:

[0074] S301, determining whether a thermal management status signal fed back by a BMS controller can be obtained;

[0075] S302. If a thermal management state signal fed back by the BMS controller is obtained, the current thermal management state is read from the thermal management state signal. S3021. It is further determined whether the current thermal management state is consistent with the target thermal management state. S3022. If the current thermal management state is consistent with the target thermal management state, it is determined that the BMS thermal management function of the BMS controller is valid, and the step of determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller is continued. S3023. Otherwise, it is determined that the BMS thermal management function of the BMS controller is invalid.

[0076] S303: If the thermal management status signal fed back by the BMS controller is not obtained, it is determined that the BMS thermal management function of the BMS controller is invalid.

[0077] Before determining whether the BMS thermal management function of the BMS controller is normal, it is crucial to first determine whether the thermal management status signal fed back by the BMS controller can be obtained through step S301. This step is equivalent to the pre-check of the entire test process, avoiding misjudgment or invalid analysis operations in the subsequent complex status judgment link due to the failure to receive feedback signals at all, and ensuring the existence of the data basis on which the test relies from the source, making the subsequent judgment steps meaningful and operable.

[0078] Exemplarily, in one embodiment, the vehicle operating condition includes a driving condition and a charging condition; when the current vehicle operating condition is a driving condition, if the minimum temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is a driving heating state; if the minimum temperature of the battery pack is lower than between 0 degrees Celsius and 35 degrees Celsius, the target thermal management state is a driving non-thermal management state; if the minimum temperature of the battery pack is higher than 35 degrees Celsius, the target thermal management state is a driving cooling state; when the current vehicle operating condition is a charging condition, if the minimum temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is a charging heating state; if the minimum temperature of the battery pack is lower than between 0 degrees Celsius and 45 degrees Celsius, the target thermal management state is a charging non-thermal management state; if the minimum temperature of the battery pack is higher than 45 degrees Celsius, the target thermal management state is a charging cooling state.

[0079] In one embodiment, sending a driving signal to the BMS controller through the simulation software may include: generating a VCU message through the simulation software, and sending the VCU message to the BMS controller by a CAN calibration analyzer.

[0080] The relevant embodiment schemes of the test bench in the present application can also be applied to the test method in the present application. The test method in the present application also has the beneficial effects of the relevant embodiment schemes of the test bench in the present application, which will not be described one by one.

[0081] In summary, the embodiments of the present application provide a test bench and test method for the thermal management function of a BMS. After the simulation software sends a driving signal to the BMS controller, the internal processing logic of the BMS controller can be triggered, so that after sending the target resistance value to the BMS controller, the BMS controller can respond as needed. The response data is also a thermal management status signal. The thermal management status signal is then analyzed by the simulation software. Since the resistance value is the resistance value presented by the digital resistor, the temperature of various conditions can be achieved without setting a real environment.

[0082] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. A test bench for BMS thermal management function, characterized in that: The test bench is used to test the BMS controller, and the test bench comprises: A host computer, the host computer is used to run simulation software, and the simulation software can send control signals; The lower computer includes a communication board and a digital rheostat. The lower computer is connected to the upper computer through the communication board. The communication board is connected to the digital rheostat. The communication board and the digital rheostat are connected to the BMS controller respectively. The digital rheostat is used to change the resistance value according to the control signal of the simulation software. The resistance value of the digital rheostat corresponds to the temperature one by one.

2. The test bench according to claim 1, characterized in that: The test bench includes a plurality of digital resistors, and the temperatures corresponding to the digital resistors include a plurality of battery temperatures, a water inlet temperature, and a water outlet temperature.

3. The test bench according to claim 1, characterized in that: The test bench also includes a connection platform, which includes a plurality of interfaces, and the interfaces are used to transfer connection lines between a plurality of components of the lower computer and the BMS controller.

4. The test bench according to claim 1, characterized in that: The communication board is a CAN calibration analyzer, and the control signal is a VCU message.

5. A method for testing the thermal management function of a BMS, characterized in that: The test method is applied to the test bench according to any one of claims 1 to 4, and the test method comprises: Sending a driving signal to the BMS controller through the simulation software, wherein the driving signal is used to indicate the current vehicle operating condition simulated by the simulation software, and the current vehicle operating condition is one of the several vehicle operating conditions; Specifying a resistance value of the digital resistor as a target resistance value, wherein the target resistance value corresponds to a target temperature; Sending the target resistance value to the BMS controller; Obtaining a thermal management status signal fed back by the BMS controller; Whether a BMS thermal management function of the BMS controller is normal is determined according to the thermal management status signal.

6. The testing method according to claim 5, characterized in that: The designating the resistance value of the digital rheostat as the target resistance value comprises: changing the resistance values ​​of a plurality of the digital rheostats to correspondingly change a plurality of target battery temperatures, target water inlet temperatures, and target water outlet temperatures; The thermal management state signal includes: the BMS controller obtains a modified target battery pack temperature difference according to the target battery temperatures, obtains a target water inlet and outlet temperature difference according to the target water inlet temperature and the target water outlet temperature, and generates a water inlet temperature demand signal and a cooling water pump duty cycle demand signal according to the target battery pack temperature difference and the target water inlet and outlet temperature difference; Determining whether the BMS thermal management function of the BMS controller is normal based on the thermal management status signal includes: determining whether the difference between the water inlet temperature demand signal and the cooling water pump duty cycle demand signal and their respective standard demand signals is within an error range; if it is determined that the difference is within the error range, determining that the BMS thermal management function of the BMS controller is normal; otherwise, determining that the BMS thermal management function of the BMS controller is abnormal.

7. The testing method according to claim 6, characterized in that: The thermal management status signal also includes a signal that the battery pack is restricted from operating. The testing method also includes: Enable the BMS controller to obtain the simulated current temperature and thermal management state of the battery pack, where the thermal management state is used for the battery pack currently being in a state of changing or maintaining a water inlet temperature; Changing the resistance value of the digital rheostat to correspondingly change the target water inlet temperature, so that the changing trend of the water inlet temperature is opposite to the trend of the water inlet temperature changing by the current thermal management state; Determining whether a signal that the battery pack is restricted in operation can be parsed from the thermal management status signal; If a signal indicating that the battery pack is operating restricted is parsed from the thermal management status signal, it is determined that the thermal management fault handling function of the BMS controller is normal; If the signal indicating that the battery pack operation is restricted cannot be parsed from the thermal management status signal, it is determined that the thermal management fault handling function of the BMS controller is abnormal.

8. The testing method according to claim 5, characterized in that: The target temperature is the lowest temperature of the battery pack. Under the current vehicle operating condition, the lowest temperature of the battery pack corresponds to a unique target thermal management state. Before determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller, the testing method further includes: Determining whether a BMS thermal management function of the BMS controller is effective; If the thermal management state signal fed back by the BMS controller is obtained, the current thermal management state is read from the thermal management state signal; whether the current thermal management state is consistent with the target thermal management state is determined; if the current thermal management state is consistent with the target thermal management state, the BMS thermal management function of the BMS controller is determined to be valid, and the step of determining whether the BMS thermal management function of the BMS controller is normal according to the thermal management state signal fed back by the BMS controller is continued; otherwise, the BMS thermal management function of the BMS controller is determined to be invalid; If the thermal management status signal fed back by the BMS controller is not obtained, it is determined that the BMS thermal management function of the BMS controller is invalid.

9. The testing method according to claim 8, characterized in that: The vehicle operating conditions include driving conditions and charging conditions; When the current vehicle operating condition is the driving condition, if the lowest temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is the driving heating state; if the lowest temperature of the battery pack is lower than 0 degrees Celsius and between 35 degrees Celsius, the target thermal management state is the driving no thermal management state; if the lowest temperature of the battery pack is higher than 35 degrees Celsius, the target thermal management state is the driving cooling state; When the current vehicle operating condition is a charging condition, if the minimum temperature of the battery pack is lower than 0 degrees Celsius, the target thermal management state is a charging heating state; if the minimum temperature of the battery pack is lower than between 0 degrees Celsius and 45 degrees Celsius, the target thermal management state is a charging no thermal management state; if the minimum temperature of the battery pack is higher than 45 degrees Celsius, the target thermal management state is a charging cooling state.

10. The testing method according to claim 5, characterized in that: The sending of the driving signal to the BMS controller through the simulation software includes: The VCU message is generated by the simulation software, and the VCU message is sent to the BMS controller by the CAN calibration analyzer.

Images