Diverter disconnection diagnosis device, vehicle-mounted battery pack and vehicle

Abstract

The invention discloses a shunt disconnection diagnosis device, a vehicle-mounted battery pack and a vehicle, and relates to the technical field of battery management. The device comprises a diverter, a positive sampling line, a negative sampling line, a sampling chip, a parallel resistor, a pull-up resistor and a pull-down resistor, the diverter is connected with a sampling port of the sampling chip through the positive sampling line and the negative sampling line, and the parallel resistor is arranged between the positive sampling line and the negative sampling line in parallel; the pull-up resistor is used for pulling up potentials corresponding to the positive sampling line and the negative sampling line to a target potential; the pull-down resistor is used for pulling down potentials corresponding to the positive sampling line and the negative sampling line to a grounding potential; and the sampling chip is used for determining a disconnection diagnosis result corresponding to the shunt based on the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor and the resistance value of the pull-down resistor. According to the invention, the technical problems of high complexity of a shunt disconnection diagnosis scheme and low accuracy of a disconnection diagnosis result are solved.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and in particular to a shunt disconnection diagnosis device, a vehicle-mounted battery pack and a vehicle. Background Art

[0002] At present, in order to achieve the power balance of the vehicle battery pack, it is usually necessary to rely on a shunt to sample the current of the vehicle battery pack. The shunt is a high-precision, high-stability current measurement device. By measuring the voltage at both ends of the shunt, the current flowing through the shunt is calculated according to Ohm's law, thereby achieving accurate monitoring of the current of the vehicle battery pack. However, the voltage sampled at both ends of the shunt is very weak. If the sampling line of the shunt is broken, a virtual voltage will be generated in the sampling line, which will affect the voltage sampling of the shunt. Therefore, it is necessary to diagnose the situation of the shunt sampling line being broken.

[0003] In the related art, the shunt line break diagnosis usually requires the use of high-precision voltage measurement tools due to the influence of the virtual voltage at both ends of the shunt sampling line when the shunt sampling line is broken, which increases the cost and complexity of the line break diagnosis scheme. In addition, the method of shunt line break diagnosis in the related art is usually unable to accurately identify the line break state of the sampling line. For example, when both ends of the sampling line are broken, it may be misjudged as a single-end sampling line break, which will result in low accuracy of the shunt line break diagnosis.

[0004] As can be seen from the above, how to reduce the complexity of the shunt disconnection diagnosis solution and improve the accuracy of the disconnection diagnosis result has become one of the important technical issues in the relevant technical field. Currently, no effective solution has been proposed for the above problems. Summary of the invention

[0005] The embodiments of the present application provide a shunt disconnection diagnosis device, a vehicle-mounted battery pack and a vehicle, so as to at least solve the technical problems of high complexity of the shunt disconnection diagnosis scheme and low accuracy of the disconnection diagnosis result.

[0006] According to one aspect of an embodiment of the present application, a shunt disconnection diagnosis device is provided, comprising: a shunt, a positive sampling line, a negative sampling line, a sampling chip, a parallel resistor, a pull-up resistor and a pull-down resistor, wherein the shunt is connected to a sampling port of the sampling chip through the positive sampling line and the negative sampling line, respectively, and the parallel resistor is arranged in parallel between the positive sampling line and the negative sampling line; the pull-up resistor is used to pull up the potentials corresponding to the positive sampling line and the negative sampling line to a target potential; the pull-down resistor is used to pull down the potentials corresponding to the positive sampling line and the negative sampling line to a ground potential; the sampling chip is used to determine a disconnection diagnosis result corresponding to the shunt based on a sampling value of the sampling port, a target potential, a resistance value of the parallel resistor, a resistance value of the pull-up resistor and a resistance value of the pull-down resistor, wherein the disconnection diagnosis result is used to characterize that at least one of the positive sampling line and the negative sampling line is disconnected.

[0007] In some embodiments, the pull-up resistor includes a first resistor and a second resistor, the first resistor is connected in parallel between the positive sampling line and an upper constant voltage source corresponding to the target potential, and the second resistor is connected in parallel between the negative sampling line and the upper constant voltage source.

[0008] In some embodiments, the pull-down resistor includes a third resistor and a fourth resistor, the third resistor is connected in parallel between the positive sampling line and a ground terminal corresponding to the ground potential, and the fourth resistor is connected in parallel between the negative sampling line and the ground terminal.

[0009] In some embodiments, a fifth resistor is connected in series to the positive sampling line, and a sixth resistor is connected in series to the negative sampling line. The resistance values ​​of the fifth resistor and the sixth resistor are both smaller than the resistance value of the parallel resistor.

[0010] In some embodiments, the sampling port includes a first analog-to-digital conversion sampling port and a second analog-to-digital conversion sampling port, the first input end of the sampling chip is connected to the shunt through a positive sampling line, the first input end is connected to the first analog-to-digital conversion sampling port, the second input end of the sampling chip is connected to the shunt through a negative sampling line, and the second input end is connected to the second analog-to-digital conversion sampling port.

[0011] In some embodiments, the sampling chip is also used to calculate the current sampling result through the resistance of the shunt and the differential voltage value between the first input terminal and the second input terminal, wherein the current sampling result is used to characterize the real-time current value flowing through the shunt.

[0012] In some embodiments, the sampling chip is also used to determine the first voltage threshold, the second voltage threshold and the third voltage threshold according to a preset diagnostic strategy, a target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor, the resistance value of the pull-down resistor, the resistance value of the fifth resistor and the resistance value of the sixth resistor.

[0013] In some embodiments, the sampling value includes a first numerical value obtained by a first analog-to-digital conversion sampling port and a second numerical value obtained by a second analog-to-digital conversion sampling port; the sampling chip is also used to: in response to the first numerical value, the second numerical value and the differential voltage value being all less than a first voltage threshold, determine that both the positive sampling line and the negative sampling line are not disconnected; in response to the difference between the first numerical value and the second voltage threshold being less than a preset threshold, the second numerical value being less than the first voltage threshold, and the difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determine that the positive sampling line is disconnected; in response to the first numerical value being less than the first voltage threshold, the difference between the second numerical value and the second voltage threshold being less than the preset threshold, and the difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determine that the negative sampling line is disconnected; in response to the difference between the first numerical value and the third voltage threshold being less than the preset threshold, the difference between the second numerical value and the third voltage threshold being less than the preset threshold, and the differential voltage value being less than the preset threshold, determine that both the positive sampling line and the negative sampling line are disconnected.

[0014] According to another aspect of an embodiment of the present application, a vehicle-mounted battery pack is further provided, which is equipped with any of the above-mentioned shunt line break diagnostic devices, and the shunt line break diagnostic device is used to perform current sampling and shunt line break diagnosis on the vehicle-mounted battery pack.

[0015] According to another aspect of an embodiment of the present application, a vehicle is provided, which is equipped with any one of the above-mentioned shunt disconnection diagnostic devices, and the shunt disconnection diagnostic device is used to perform current sampling and shunt disconnection diagnosis on a target battery of the vehicle.

[0016] In an embodiment of the present application, the present invention comprises: a shunt, a positive sampling line, a negative sampling line, a sampling chip, a parallel resistor, a pull-up resistor and a pull-down resistor, wherein the shunt is connected to the sampling port of the sampling chip through the positive sampling line and the negative sampling line respectively, and the parallel resistor is arranged in parallel between the positive sampling line and the negative sampling line; the pull-up resistor is used to pull up the potentials corresponding to the positive sampling line and the negative sampling line to the target potential; the pull-down resistor is used to pull down the potentials corresponding to the positive sampling line and the negative sampling line to the ground potential; the sampling chip is used to determine the line break diagnosis result corresponding to the shunt based on the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor and the resistance value of the pull-down resistor, wherein the line break diagnosis result is used to characterize that at least one of the positive sampling line and the negative sampling line is broken.

[0017] It is easy to notice that the embodiment of the present application can accurately detect whether the positive sampling line and / or negative sampling line of the shunt is broken by introducing a parallel resistor, a pull-up resistor and a pull-down resistor, using the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor and the resistance value of the pull-down resistor. Therefore, the embodiment of the present application achieves the purpose of more accurately determining the shunt break diagnosis result, thereby achieving the technical effect of reducing the complexity of the shunt break diagnosis scheme and improving the accuracy of the break diagnosis result, thereby solving the technical problem of high complexity of the shunt break diagnosis scheme and low accuracy of the break diagnosis result. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and the related descriptions of the embodiments are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 is a structural schematic diagram of a shunt disconnection diagnosis device according to an embodiment of the present application;

[0020] Figure 2 It is a circuit schematic diagram of a shunt disconnection diagnosis device according to an embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments only include a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0022] First, the operating environment of the embodiment of the present application is exemplarily described. Under the above operating environment, the embodiment of the present application provides a shunt disconnection diagnostic device. The device can be used in preset application scenarios that have high requirements for the reliability and safety of the battery management system. The above preset application scenarios may include the following scenarios in the field of household cars: electric vehicle battery management (such as safety monitoring of electric vehicle batteries, charge and discharge control of electric vehicle batteries, etc.), hybrid vehicle energy management (such as energy distribution control between the engine and the battery) scenario. In addition, the above preset application scenarios may also include but are not limited to: energy storage system monitoring scenarios, battery factory testing scenarios, and electronic equipment (such as laptops, tablets, smart phones, smart watches, etc.) battery monitoring scenarios.

[0023] Under the above operating environment, the embodiment of the present application provides the following Figure 1 The schematic diagram of the structure of the shunt disconnection diagnosis device shown in FIG. Figure 1 is a structural schematic diagram of a shunt disconnection diagnosis device according to an embodiment of the present application, such as Figure 1 As shown, the device includes: a shunt, a positive sampling line, a negative sampling line, a sampling chip, a parallel resistor, a pull-up resistor and a pull-down resistor, wherein the shunt is connected to the sampling port of the sampling chip through the positive sampling line and the negative sampling line respectively, and the parallel resistor is arranged in parallel between the positive sampling line and the negative sampling line; the pull-up resistor is used to pull up the potentials corresponding to the positive sampling line and the negative sampling line to the target potential; the pull-down resistor is used to pull down the potentials corresponding to the positive sampling line and the negative sampling line to the ground potential; the sampling chip is used to determine the disconnection diagnosis result corresponding to the shunt based on the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor and the resistance value of the pull-down resistor, wherein the disconnection diagnosis result is used to characterize that at least one of the positive sampling line and the negative sampling line is disconnected.

[0024] The above-mentioned shunt can be a high-precision current detection element. The shunt can calculate the current flowing through it by measuring the voltage in the sampling lines at both ends of it. The shunt can be used to monitor the current of the battery pack. The above-mentioned positive sampling line can connect the positive pole of the shunt and the sampling port of the sampling chip. The positive sampling line can be used to transmit the voltage signal at the positive end of the shunt to the sampling chip. The above-mentioned negative sampling line can connect the negative pole of the shunt and the sampling port of the sampling chip. The negative sampling line can be used to transmit the voltage signal at the negative end of the shunt to the sampling chip. The above-mentioned pull-up resistor can be used to limit the potential within the input voltage range of the chip. The above-mentioned pull-down resistor can be used to absorb current. The above-mentioned target potential can be used to limit the input voltage value of the sampling chip pin input end.

[0025] By setting a parallel resistor between the positive sampling line and the negative sampling line, it can be ensured that when any sampling line is disconnected, virtual pressure is avoided on the sampling lines at both ends of the shunt, thereby ensuring the accuracy of the disconnection diagnosis result.

[0026] The specific implementation steps of the sampling chip determining the disconnection diagnosis result corresponding to the shunt based on the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor, and the resistance value of the pull-down resistor can be: the sampling chip receives the voltage signal of the positive end of the shunt transmitted by the positive sampling line and the voltage signal of the negative end of the shunt transmitted by the negative sampling line through the sampling port, and then combines the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor, and the resistance value of the pull-down resistor to analyze the voltage signal of the positive end and the voltage signal of the negative end through a pre-set algorithm to determine whether the sampling line of the shunt is disconnected, and determine the disconnection state of the sampling line of the shunt, and determine the disconnection diagnosis result corresponding to the shunt. The above disconnection state can include: the positive sampling line is disconnected, the negative sampling line is disconnected, and the positive sampling line and the negative sampling line are disconnected at the same time.

[0027] The embodiment of the present application can reduce the impact of external interference or internal changes in the circuit on the disconnection diagnosis result by comprehensively analyzing multiple parameters. Compared with relying on a single parameter, the embodiment of the present application can more accurately determine the disconnection status of the shunt sampling line, thereby improving the accuracy and reliability of the shunt disconnection diagnosis result.

[0028] It should be noted that the above-mentioned disconnection diagnosis result can also be used to indicate that both the positive sampling line and the negative sampling line are not disconnected.

[0029] It is easy to understand that, through the above-mentioned shunt line breakage diagnosis device, on the one hand, in the embodiment of the present application, the shunt, positive sampling line, negative sampling line, sampling chip, parallel resistor, pull-up resistor and pull-down resistor are used to reduce the dependence of the shunt line breakage diagnosis scheme on high-precision voltage measurement equipment, reduce the cost and complexity of the shunt line breakage diagnosis scheme, and the scheme is more feasible in actual engineering; on the other hand, in the embodiment of the present application, by comprehensively analyzing multiple parameters, the sampling chip can identify the situation where the positive sampling line, the negative sampling line, or the positive sampling line and the negative sampling line are broken at the same time, and can more accurately judge the broken state of the shunt sampling line. Therefore, the shunt sampling line breakage diagnosis circuit of the embodiment of the present application is simpler, and the determined shunt line breakage diagnosis result is more accurate.

[0030] As an optional implementation, the pull-up resistor includes a first resistor and a second resistor, the first resistor is connected in parallel between the positive sampling line and the upper constant voltage source corresponding to the target potential, and the second resistor is connected in parallel between the negative sampling line and the upper constant voltage source.

[0031] The upper constant voltage source may be a power source that provides a constant voltage to the circuit.

[0032] By connecting a pull-up resistor in parallel between the sampling line of the shunt and a constant target potential, the embodiment of the present application can ensure that the potential of the sampling line of the shunt is maintained at a stable potential value, avoiding the situation where the sampling line of the shunt is in a suspended state, so that the sampling chip can obtain more accurate data during sampling.

[0033] In addition, when the sampling line of the shunt is broken, virtual voltage may appear at both ends of the sampling line. The embodiment of the present application connects a pull-up resistor in parallel between the sampling line of the shunt and a constant target potential. When the sampling line is disconnected, it can still ensure that the sampling line potential will not change significantly due to the influence of the virtual voltage, thereby improving the accuracy of the disconnection diagnosis results.

[0034] In an exemplary application scenario, Figure 2 is a circuit schematic diagram of a shunt disconnection diagnosis device according to an embodiment of the present application, such as Figure 2 As shown, the pull-up resistor includes a first resistor (denoted as R4) and a second resistor (denoted as R5), R4 is connected in parallel between the positive sampling line and the upper constant voltage source corresponding to the target potential (such as 2V), and R5 is connected in parallel between the negative sampling line and the upper constant voltage source.

[0035] It is easy to understand that, through the above-mentioned shunt disconnection diagnosis device, in the embodiment of the present application, the use of pull-up resistors can improve the accuracy of the disconnection diagnosis result and the robustness of the diagnosis device.

[0036] As an optional implementation, the pull-down resistor includes a third resistor and a fourth resistor, the third resistor is connected in parallel between the positive sampling line and a ground terminal corresponding to the ground potential, and the fourth resistor is connected in parallel between the negative sampling line and the ground terminal.

[0037] By connecting a pull-down resistor in parallel between the sampling line and the ground terminal corresponding to the ground potential, the embodiment of the present application can ensure that when no current flows through the shunt, the potential of the sampling line can be stabilized at a predictable low level, providing a clear low voltage reference point to ensure that the sampling chip avoids the influence of noise caused by interference from environmental factors when sampling.

[0038] In addition, when the sampling line of the shunt is broken, if only a pull-up resistor is set in the circuit, the potential of the sampling line may drift due to the uncertainty of the circuit, resulting in a virtual voltage. The embodiment of the present application can lower the potential of the sampling line by connecting a pull-down resistor in parallel between the sampling line and the ground end corresponding to the ground potential, thereby avoiding errors in the broken line diagnosis results due to the influence of the virtual voltage and improving the accuracy of the broken line diagnosis results.

[0039] In an exemplary application scenario, Figure 2As shown, the pull-down resistor includes a third resistor (denoted as R6) and a fourth resistor (denoted as R7), R6 is connected in parallel between the positive sampling line and the ground terminal corresponding to the ground potential, and R7 is connected in parallel between the negative sampling line and the ground terminal.

[0040] It is easy to understand that, through the above-mentioned shunt disconnection diagnosis device, in the embodiment of the present application, the use of a pull-down resistor can improve the accuracy of the disconnection diagnosis result and the robustness of the diagnosis device.

[0041] As an optional implementation, a fifth resistor is provided in series on the positive sampling line, and a sixth resistor is provided in series on the negative sampling line, and the resistance values ​​of the fifth resistor and the sixth resistor are both smaller than the resistance value of the parallel resistor.

[0042] When the sampling line of the shunt is disconnected, since a parallel resistor is provided between the positive sampling line and the negative sampling line, the current shunted when the shunt sampling line is not disconnected will flow through the parallel resistor, generating a relatively high voltage. By utilizing the fifth resistor connected in series to the positive sampling line and the sixth resistor connected in series to the negative sampling line, a low impedance path can be formed when the shunt sampling line is disconnected, so that part of the current passes through, thereby generating a predictable voltage change on the sampling line that is easier to be collected and distinguished by the sampling chip, thereby improving the accuracy of the sampling chip in collecting the sampling signal.

[0043] It should be noted that, since the resistance of the fifth resistor and the sixth resistor is small, when the shunt sampling line is not disconnected, the impact on the voltage at both ends of the shunt sampling line can be ignored, so it will not interfere with the sampling of the voltage at both ends of the sampling line.

[0044] Still like Figure 2 As shown, a fifth resistor (denoted as R1) having a resistance value smaller than R8 is arranged in series on the positive sampling line, and a sixth resistor (denoted as R2) having a resistance value smaller than R8 is arranged in series on the negative sampling line.

[0045] It is easy to understand that, through the above-mentioned shunt breakage diagnosis device, in the embodiment of the present application, by connecting resistors in series on the positive and negative sampling lines, the sampling signal can be controlled more accurately, thereby improving the accuracy of the sampling signal.

[0046] As an optional implementation, the sampling port includes a first analog-to-digital conversion sampling port and a second analog-to-digital conversion sampling port, the first input end of the sampling chip is connected to the shunt through a positive sampling line, the first input end is connected to the first analog-to-digital conversion sampling port, the second input end of the sampling chip is connected to the shunt through a negative sampling line, and the second input end is connected to the second analog-to-digital conversion sampling port.

[0047] Generally speaking, it is difficult to sample the current of the shunt while diagnosing the shunt sampling line disconnection using the shunt sampling line disconnection diagnosis circuit in the related art. Figure 2 As shown, in the embodiment of the present application, the first input terminal (denoted as A input terminal) is connected to the first analog-to-digital conversion sampling port (denoted as ADC1), that is, the positive sampling line of the shunt is simultaneously connected to the first input terminal and the first analog-to-digital conversion sampling port, and the second input terminal (denoted as B input terminal) is connected to the second analog-to-digital conversion sampling port (denoted as ADC2), that is, the negative sampling line of the shunt is simultaneously connected to the second input terminal and the second analog-to-digital conversion sampling port. The sampling chip can perform current sampling on the shunt by using the electrical signals of the first input terminal and the second input terminal while diagnosing the line break of the sampling lines at both ends of the shunt.

[0048] It is easy to understand that through the above-mentioned shunt line break diagnosis device, in the embodiment of the present application, the analog-to-digital conversion sampling port of the sampling chip is used to convert the analog electrical signal collected at the input end into a digital signal, which is more conducive to data processing and analysis, and improves the accuracy of the sampled data. In addition, it is also possible to decouple shunt sampling and shunt line break diagnosis, and perform line break diagnosis on the shunt while using the shunt for sampling.

[0049] As an optional implementation, the sampling chip is also used to calculate through the resistance of the shunt and the differential voltage value between the first input terminal and the second input terminal to obtain a current sampling result, wherein the current sampling result is used to characterize the real-time current value flowing through the shunt.

[0050] The differential voltage value may be an absolute value of a difference between a voltage value at the first input terminal and a voltage value at the second input terminal.

[0051] By analyzing the differential voltage across the shunt, the sampling chip can quickly and accurately calculate the real-time current value flowing through the shunt, and can obtain the shunt current sampling result in a timely and accurate manner, thereby ensuring that the battery management system can grasp the status of the battery pack in real time and can process the battery pack more promptly and accurately (such as battery pack power management, battery pack fault warning, battery pack safety protection, etc.).

[0052] In addition, the computational logic unit inside the sampling chip has higher robustness. Using the computational logic unit inside the sampling chip to perform current calculations avoids the impact of external environmental factors (such as temperature changes, electromagnetic interference, hardware fluctuations, etc.) on the accuracy of current sampling, thereby improving the stability and accuracy of the current sampling results and enhancing the overall stability and anti-interference ability of the battery management system.

[0053] It is easy to understand that, through the above-mentioned shunt line breakage diagnostic device, in the embodiment of the present application, the differential voltage value is used to reduce the influence of common mode noise, improve the anti-interference ability of the shunt line breakage diagnostic device, and improve the accuracy of the shunt current sampling result.

[0054] As an optional implementation, the sampling chip is also used to determine the first voltage threshold, the second voltage threshold and the third voltage threshold according to a preset diagnostic strategy, a target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor, the resistance value of the pull-down resistor, the resistance value of the fifth resistor and the resistance value of the sixth resistor.

[0055] The above-mentioned preset diagnostic strategy can be obtained by combining circuit characteristics with historical shunt disconnection diagnosis schemes. The preset diagnostic strategy may include multiple test conditions (such as multiple conditions corresponding to disconnection of the shunt positive end sampling line, multiple conditions corresponding to disconnection of the shunt negative end sampling line, multiple conditions corresponding to disconnection of the sampling lines at both ends of the shunt, etc.) and corresponding voltage threshold algorithms. The preset diagnostic strategy may also include a threshold correction strategy (such as a correction strategy set based on experience, a threshold correction strategy obtained through a deep learning algorithm, etc.).

[0056] It should be noted that, in the process of determining the preset diagnosis strategy, the influence of environmental interference factors on the voltage value is also considered, such as temperature change, circuit noise, power supply fluctuation, etc.

[0057] The first voltage threshold can be used to indicate the maximum voltage when the sampling lines at both ends of the shunt are in an unbroken state. The second voltage threshold can be used to indicate the maximum voltage when the sampling line at the positive or negative end of the shunt is in a broken state. The third voltage threshold can be used to indicate the maximum voltage when the sampling lines at both ends of the shunt are in a broken state.

[0058] In an exemplary application scenario, Figure 2 As shown, R4, R5, R6, and R7 are set to resistors with the same resistance value, and R1 and R2 are set to resistors with the same resistance value, then the first voltage threshold can be determined by the following steps: using the resistance value of R1, the resistance value of R2, the resistance value of R4, the resistance value of R5, the resistance value of R6, the resistance value of R7, the resistance value of R8, and the target potential, the circuit is analyzed according to Ohm's law, and the voltage value at both ends of the shunt is calculated when the sampling lines at both ends of the shunt are in a state where the line is not broken and the current can flow normally through the shunt, and the first voltage threshold is determined in combination with the preset diagnostic strategy.

[0059] Still like Figure 2As shown, the second voltage threshold can be determined by the following steps: first, using the resistance value of R1, the resistance value of R4, the resistance value of R6, the resistance value of R8, and the target potential, the sampling line circuit at the positive end of the shunt is analyzed according to Ohm's law, and the voltage value at both ends of the shunt is calculated when the sampling line at only the positive end of the shunt is in a state of disconnected current; secondly, using the resistance value of R2, the resistance value of R5, the resistance value of R7, the resistance value of R8, and the target potential, the sampling line circuit at the positive end of the shunt is analyzed according to Ohm's law, and the voltage value at both ends of the shunt is calculated when the sampling line at only the negative end of the shunt is in a state of disconnected current; finally, the second voltage threshold is determined by combining the voltage values ​​of the sampling lines at both ends when the sampling line at only the positive end of the shunt is disconnected, the voltage values ​​of the sampling lines at both ends when the sampling line at only the negative end of the shunt is disconnected, and the preset diagnostic strategy.

[0060] Still like Figure 2 As shown, the third voltage threshold can be determined by the following steps: using the resistance value of R1, the resistance value of R2, the resistance value of R4, the resistance value of R5, the resistance value of R6, the resistance value of R7, the resistance value of R8, and the target potential, analyzing the circuit according to Ohm's law, calculating the voltage value at both ends of the shunt when the sampling lines at both ends of the shunt are in a state where the broken current can flow normally through the shunt, and combining with the preset diagnostic strategy to determine the third voltage threshold.

[0061] It is easy to understand that through the above-mentioned shunt disconnection diagnosis device, in the embodiment of the present application, by utilizing the preset diagnostic strategy, target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor, the resistance value of the pull-down resistor, the resistance value of the fifth resistor and the resistance value of the sixth resistor, the threshold value corresponding to the sampling line of the shunt in different states can be more accurately determined, which can improve the accuracy of disconnection diagnosis.

[0062] As an optional implementation, the sampling value includes a first value obtained by a first analog-to-digital conversion sampling port and a second value obtained by a second analog-to-digital conversion sampling port; the sampling chip is also used to: in response to the first value, the second value and the differential voltage value being all less than a first voltage threshold, determine that both the positive sampling line and the negative sampling line are not disconnected; in response to the difference between the first value and the second voltage threshold being less than a preset threshold, the second value being less than the first voltage threshold, and the difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determine that the positive sampling line is disconnected; in response to the first value being less than the first voltage threshold, the difference between the second value and the second voltage threshold being less than the preset threshold, and the difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determine that the negative sampling line is disconnected; in response to the difference between the first value and the third voltage threshold being less than the preset threshold, the difference between the second value and the third voltage threshold being less than the preset threshold, and the differential voltage value being less than the preset threshold, determine that both the positive sampling line and the negative sampling line are disconnected.

[0063] The above-mentioned preset threshold may be preset based on historical experience, and the preset threshold may be an extremely small value.

[0064] It should be noted that the first voltage threshold, the second voltage threshold, and the third voltage threshold are all greater than the preset threshold.

[0065] In response to the first value, the second value and the differential voltage value being all less than the first voltage threshold, determining that the positive sampling line and the negative sampling line are both not disconnected may be specifically implemented by: the sampling chip acquires the voltage value of the positive sampling line of the shunt through the first analog-to-digital conversion sampling port, and the sampling chip acquires the voltage value of the negative sampling line of the shunt through the second analog-to-digital conversion sampling port.

[0066] In an exemplary application scenario, Figure 2 As shown, the first voltage threshold is recorded as Q1, the second voltage threshold is recorded as Q2, the third voltage threshold is recorded as Q3, and the preset threshold is recorded as Q4. The shunt disconnection diagnosis scheme can be shown in the following Table 1:

[0067] Table 1

[0068] Shunt disconnection diagnosis results First value Second value Differential Voltage Both ends are not disconnected <Q1 <Q1 <Q1 Only the positive sampling line is broken ≈Q2 <Q1 ≈Q2 Only the negative sampling line is broken <Q1 ≈Q2 ≈Q2 Both ends are disconnected ≈Q3 ≈Q3 <Q4

[0069] As shown in Table 1, in the process of performing disconnection diagnosis on the sampling lines at both ends of the shunt, if the following three conditions (condition one, condition two, and condition three) are met, it is determined that the disconnection diagnosis result of the shunt is that the sampling lines at both ends of the shunt are in a state of not being disconnected:

[0070] Condition 1: The first value obtained by the first analog-to-digital conversion sampling port is less than the first voltage threshold Q1;

[0071] Condition 2: the second value obtained by the second analog-to-digital conversion sampling port is less than the first voltage threshold Q1;

[0072] Condition three: the differential voltage is less than the first voltage threshold Q1.

[0073] Still as shown in Table 1, in the process of performing disconnection diagnosis on the sampling lines at both ends of the shunt, if the following three conditions (conditions 4, 5 and 6) are met, it is determined that the disconnection diagnosis result of the shunt is that only the sampling lines at the positive end of the shunt are in a disconnected state:

[0074] Condition 4: The first value obtained by the first analog-to-digital conversion sampling port is approximately equal to the second voltage threshold Q2;

[0075] Condition 5: The second value obtained by the second analog-to-digital conversion sampling port is less than the first voltage threshold Q1;

[0076] Condition six: the differential voltage is approximately equal to the second voltage threshold Q2.

[0077] As shown in Table 1, in the process of performing disconnection diagnosis on the sampling lines at both ends of the shunt, if the following three conditions (conditions seven, eight and nine) are met, it is determined that the disconnection diagnosis result of the shunt is that only the sampling lines at the positive end of the shunt are in a disconnected state:

[0078] Condition 7: The first value obtained by the first analog-to-digital conversion sampling port is less than the first voltage threshold Q1;

[0079] Condition 8: The second value obtained by the second analog-to-digital conversion sampling port is approximately equal to the second voltage threshold Q2;

[0080] Condition nine: the differential voltage is approximately equal to the second voltage threshold Q2.

[0081] As shown in Table 1, in the process of performing disconnection diagnosis on the sampling lines at both ends of the shunt, if the following three conditions (condition 10, condition 11 and condition 12) are met, it is determined that the disconnection diagnosis result of the shunt is that only the sampling lines at the positive end of the shunt are in a disconnected state:

[0082] Condition 10: The first value obtained by the first analog-to-digital conversion sampling port is approximately equal to the third voltage threshold Q3;

[0083] Condition 11: The second value obtained by the second analog-to-digital conversion sampling port is approximately equal to the third voltage threshold Q3;

[0084] Condition 12: The differential voltage is less than the preset threshold Q4.

[0085] It should be noted that when the absolute value of the difference between the first numerical value obtained by the first analog-to-digital conversion sampling port and the second voltage threshold Q2 is less than the preset threshold value Q4, it can be considered that the first numerical value obtained by the first analog-to-digital conversion sampling port is approximately equal to the second voltage threshold value Q2; when the absolute value of the difference between the first numerical value obtained by the first analog-to-digital conversion sampling port and the third voltage threshold value Q3 is less than the preset threshold value Q4, it can be considered that the first numerical value obtained by the first analog-to-digital conversion sampling port is approximately equal to the third voltage threshold value Q3; when the absolute value of the difference between the second numerical value obtained by the second analog-to-digital conversion sampling port and the second voltage threshold value Q2 is less than the preset threshold value Q4, it can be considered that the second numerical value obtained by the second analog-to-digital conversion sampling port is approximately equal to the second voltage threshold value Q2; when the absolute value of the difference between the second numerical value obtained by the second analog-to-digital conversion sampling port and the third voltage threshold value Q3 is less than the preset threshold value Q4, it can be considered that the second numerical value obtained by the second analog-to-digital conversion sampling port is approximately equal to the third voltage threshold value Q3.

[0086] It is easy to understand that through the above-mentioned shunt breakage diagnosis device, in the embodiment of the present application, by utilizing multiple thresholds, the sampling chip automatically identifies the status of the sampling lines at both ends of the shunt and performs a breakage diagnosis on the shunt, and can accurately judge the status of the sampling lines at both ends of the shunt, thereby avoiding the misdiagnosis of a breakage at both ends of the shunt sampling line as a single-end breakage, thereby improving the reliability and safety of the shunt breakage diagnosis scheme.

[0087] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0088] According to an embodiment of the present invention, there is also provided an implementation of a vehicle-mounted battery pack, which is equipped with the above-mentioned shunt line breakage diagnostic device, and the shunt line breakage diagnostic device is used to perform current sampling and shunt line breakage diagnosis on the vehicle-mounted battery pack.

[0089] According to an embodiment of the present invention, there is also provided an embodiment of a vehicle, which is equipped with the above-mentioned shunt disconnection diagnostic device, and the shunt disconnection diagnostic device is used to perform current sampling and shunt disconnection diagnosis on a target battery of the vehicle.

[0090] According to an embodiment of the present invention, a method for managing a vehicle battery pack is also provided, the method comprising: initializing and configuring a sampling chip; sampling the voltage at both ends of a shunt sampling line using the sampling chip to obtain a sampled voltage value; calculating a sampled current value of the shunt based on the sampled voltage value and Ohm's law; performing a line break diagnosis on the sampling lines at both ends of the shunt by the sampling chip according to the sampled voltage value, a first voltage threshold, a second voltage threshold, a third voltage threshold and a preset diagnostic strategy to obtain a line break diagnosis result; in response to the line break diagnosis result being that the sampling line at the positive end and / or the negative end of the shunt is in a line break state, the sampling chip sends an alarm signal to the battery management system and records the line break diagnosis result and the line break diagnosis time.

[0091] Optionally, using a sampling chip to sample the voltage at both ends of a shunt sampling line may also include: using a first sampling port of the sampling chip to sample the voltage at the positive end of the shunt sampling line to obtain a first voltage sampling value, and using a second sampling port of the sampling chip to sample the voltage at the negative end of the shunt sampling line to obtain a second voltage sampling value.

[0092] Optionally, based on the sampled voltage value, the first voltage threshold, the second voltage threshold, the third voltage threshold and the preset diagnostic strategy, the sampling chip performs a broken wire diagnosis on the sampling lines at both ends of the shunt, and obtaining the broken wire diagnosis result may also include: obtaining a first voltage sampling value of the first sampling port of the sampling chip and a second voltage sampling value of the second sampling port of the sampling chip, and calculating the absolute value of the differential voltage value between the first voltage sampling value and the second voltage sampling value based on the first voltage sampling value and the second voltage sampling value.

[0093] Optionally, in response to the disconnection diagnosis result that the positive and / or negative sampling lines of the shunt are in a disconnected state, the sampling chip sends an alarm signal to the battery management system, and recording the disconnection diagnosis result and the disconnection diagnosis time may also include: in response to the disconnection diagnosis result that only the positive sampling line of the shunt is in a disconnected state, the sampling chip sends a first alarm signal to the battery management system; in response to the disconnection diagnosis result that only the negative sampling line of the shunt is in a disconnected state, the sampling chip sends a second alarm signal to the battery management system; in response to the disconnection diagnosis result that both the positive and negative ends of the shunt are in a disconnected state, the sampling chip sends a third alarm signal to the battery management system.

[0094] In the above-mentioned multiple embodiments of the present application, the description of each embodiment has different emphases. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0095] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of multiple modules can be a logical function division, and there can be any other possible division methods when actually implemented in the application scenario; for another example, multiple modules (or units or components in the modules) can be combined with each other and can be integrated into another system. For example, some features of the method embodiments described above can be ignored or skipped.

[0096] It should be noted that in the above-mentioned embodiments, the modules, components or units described as separate parts can be physically separated or physically integrated. The parts displayed as modules or units can be physical modules or physical units, or virtual modules or virtual units, that is, multiple modules or multiple units can be in the same position, or distributed in multiple positions or multiple spaces. In the application scenario, according to the actual needs of the scenario, some or all of the multiple modules or multiple units can be selected to implement the technical solutions of the embodiments of the present application, thereby achieving the corresponding technical objectives.

[0097] In particular, for an integrated functional module or functional unit, if it is implemented in the form of a software functional unit and sold or used as an independent product, the module or functional unit can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can essentially or in other words, the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application.

[0098] 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 modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A shunt disconnection diagnosis device, characterized in that: include: A shunt, a positive sampling line, a negative sampling line, a sampling chip, a parallel resistor, a pull-up resistor and a pull-down resistor, wherein the shunt is connected to the sampling port of the sampling chip through the positive sampling line and the negative sampling line respectively, and the parallel resistor is arranged in parallel between the positive sampling line and the negative sampling line; The pull-up resistor is used to pull up the potentials corresponding to the positive sampling line and the negative sampling line to a target potential; The pull-down resistor is used to pull down the potential corresponding to the positive sampling line and the negative sampling line to the ground potential; The sampling chip is used to determine a line break diagnosis result corresponding to the shunt based on the sampling value of the sampling port, the target potential, the resistance value of the parallel resistor, the resistance value of the pull-up resistor and the resistance value of the pull-down resistor, wherein the line break diagnosis result is used to characterize that at least one of the positive sampling line and the negative sampling line is broken.

2. The shunt disconnection diagnosis device according to claim 1, characterized in that: The pull-up resistor includes a first resistor and a second resistor, the first resistor is connected in parallel between the positive sampling line and an upper constant voltage source corresponding to the target potential, and the second resistor is connected in parallel between the negative sampling line and the upper constant voltage source.

3. The shunt disconnection diagnosis device according to claim 1, characterized in that: The pull-down resistor includes a third resistor and a fourth resistor. The third resistor is connected in parallel between the positive sampling line and a ground terminal corresponding to the ground potential. The fourth resistor is connected in parallel between the negative sampling line and the ground terminal.

4. The shunt disconnection diagnosis device according to claim 1, characterized in that: A fifth resistor is arranged in series on the positive sampling line, and a sixth resistor is arranged in series on the negative sampling line. The resistance value of the fifth resistor and the resistance value of the sixth resistor are both smaller than the resistance value of the parallel resistor.

5. The shunt disconnection diagnosis device according to claim 4, characterized in that: The sampling port includes a first analog-to-digital conversion sampling port and a second analog-to-digital conversion sampling port. The first input end of the sampling chip is connected to the shunt through the positive sampling line, the first input end is connected to the first analog-to-digital conversion sampling port, the second input end of the sampling chip is connected to the shunt through the negative sampling line, and the second input end is connected to the second analog-to-digital conversion sampling port.

6. The shunt disconnection diagnosis device according to claim 5, characterized in that: The sampling chip is also used to calculate through the resistance value of the shunt and the differential voltage value between the first input terminal and the second input terminal to obtain a current sampling result, wherein the current sampling result is used to characterize a real-time current value flowing through the shunt.

7. The shunt disconnection diagnosis device according to claim 6, characterized in that: The sampling chip is also used for: A first voltage threshold, a second voltage threshold and a third voltage threshold are determined according to a preset diagnostic strategy, the target potential, the resistance of the parallel resistor, the resistance of the pull-up resistor, the resistance of the pull-down resistor, the resistance of the fifth resistor and the resistance of the sixth resistor.

8. The shunt disconnection diagnosis device according to claim 7, characterized in that: The sampling value includes a first value obtained by the first analog-to-digital conversion sampling port and a second value obtained by the second analog-to-digital conversion sampling port; the sampling chip is also used for: In response to the first value, the second value, and the differential voltage value being all smaller than the first voltage threshold, determining that the positive sampling line and the negative sampling line are both not disconnected; In response to a difference between the first value and the second voltage threshold being less than a preset threshold, the second value being less than the first voltage threshold, and a difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determining that the positive sampling line is disconnected; In response to the first value being less than the first voltage threshold, the difference between the second value and the second voltage threshold being less than the preset threshold, and the difference between the differential voltage value and the second voltage threshold being less than the preset threshold, determining that the negative sampling line is disconnected; In response to the difference between the first value and the third voltage threshold being less than the preset threshold, the difference between the second value and the third voltage threshold being less than the preset threshold, and the differential voltage value being less than the preset threshold, it is determined that both the positive sampling line and the negative sampling line are disconnected.

9. A vehicle-mounted battery pack, characterized in that: The shunt disconnection diagnostic device according to any one of claims 1 to 8 is configured, and the shunt disconnection diagnostic device is used to perform current sampling and shunt disconnection diagnosis on the vehicle-mounted battery pack.

10. A vehicle, characterized in that: The shunt disconnection diagnostic device according to any one of claims 1 to 8 is configured to perform current sampling and shunt disconnection diagnosis on a target battery of the vehicle.

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