Thermal failure protection methods, devices, equipment and storage media

Abstract

This invention discloses a thermal failure protection method, device, equipment, and storage medium, belonging to the field of new energy vehicle technology. The invention acquires the real-time current of the vehicle's high-voltage circuit; determines whether the vehicle has a thermal failure risk based on the real-time current of the high-voltage circuit; if the vehicle has a thermal failure risk, determines a target thermal failure protection strategy based on the real-time current of the high-voltage circuit; and performs thermal failure protection on the vehicle according to the target thermal failure protection strategy. This method can achieve corresponding thermal failure protection for different high-voltage circuits, providing more comprehensive protection for the high-voltage circuit, improving the high-voltage safety performance of the product, further preventing spontaneous combustion of electric vehicles, and ensuring the personal and property safety of users.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, and in particular to a thermal failure protection method, device, equipment and storage medium. Background Technology

[0002] Thermal failure design is particularly important in the design of new energy vehicles, involving various high-voltage subsystems. High-voltage connection components, as a crucial part of the high-voltage system, require design at three levels: vehicle, system, and component. For example, based on battery characteristics, the lower the State of Charge (SOC), the lower the battery terminal voltage, the lower the battery temperature, and the higher the battery internal resistance. According to I = U / R, where U is the battery terminal voltage, R is the battery internal resistance, and I is the real-time current, when the battery SOC is low (low terminal voltage) and the battery temperature is low (high internal resistance), if a short circuit occurs, the real-time current is small. When the current is less than a certain threshold, the fuse blows later than the wiring harness smoke and the relay blows. The fuse cannot protect the high-voltage circuit, potentially causing the vehicle to spontaneously combust.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main objective of this invention is to provide a thermal failure protection method, device, equipment, and storage medium, aiming to solve the technical problem that the existing technology cannot fully protect the high-voltage circuit, causing electric vehicles to spontaneously combust and harming the personal and property safety of users.

[0005] To achieve the above objectives, the present invention provides a thermal failure protection method, which includes the following steps:

[0006] Obtain the real-time current of the vehicle's high-voltage circuit;

[0007] The risk of thermal failure in the vehicle is determined based on the real-time current of the high-voltage circuit.

[0008] If the vehicle is at risk of thermal failure, the target thermal failure protection strategy is determined based on the real-time current of the high-voltage circuit.

[0009] Thermal failure protection is performed on the vehicle according to the target thermal failure protection strategy.

[0010] Optionally, determining the target thermal failure protection strategy based on the real-time current of the high-voltage circuit includes:

[0011] When the real-time current of the high-voltage circuit is within the first protection range, the first thermal failure protection strategy is taken as the target thermal failure protection strategy.

[0012] When the real-time current of the high-voltage circuit is within the second protection range, the second thermal failure protection strategy is used as the target thermal failure protection strategy, and the lower limit of the first protection range is the upper limit of the second protection range.

[0013] Optionally, before setting the first thermal failure protection strategy as the target thermal failure protection strategy when the real-time current in the high-voltage circuit is within the protection current range corresponding to the fuse, the method further includes:

[0014] Obtain the smoke emission characteristic curves of the wiring harness, the bronze plate of the battery pack, and the fuse corresponding to the vehicle.

[0015] The first reference current value is determined based on the smoke emission characteristic curve of the wiring harness and the smoke emission characteristic curve of the fuse.

[0016] The second reference current value is determined based on the smoke emission characteristic curve of the battery pack copper plate and the smoke emission characteristic curve of the fuse.

[0017] The first protection range is obtained by taking the maximum value between the first reference current value and the second reference current value as the first target current value and taking the first target current value as the lower limit value.

[0018] Optionally, before setting the second thermal failure protection strategy as the target thermal failure protection strategy when the real-time current of the high-voltage circuit is within the second protection range, the method further includes:

[0019] Calculate the third reference current value corresponding to the smoke emission characteristic curve of the wiring harness, the fourth reference current value corresponding to the smoke emission characteristic curve of the battery pack copper plate, and the fifth reference current value corresponding to the smoke emission characteristic curve of the fuse according to the preset curve slope.

[0020] The minimum value among the third reference current value, the fourth reference current value, and the fifth reference current value is used as the second target current value, and the first target current value is used as the upper limit value and the second target current value is used as the lower limit value to obtain the second protection range.

[0021] Optionally, the step of performing thermal failure protection on the vehicle according to the target thermal failure protection strategy includes:

[0022] When the target thermal failure protection strategy is the first thermal failure protection strategy, thermal failure protection of the vehicle is achieved by blowing the fuse.

[0023] When the target thermal failure protection strategy is the second thermal failure protection strategy, the vehicle is subjected to a high-pressure operation based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle.

[0024] Optionally, before performing high-voltage operation on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle, the method further includes:

[0025] Obtain the load characteristic curve corresponding to the vehicle;

[0026] Based on the second protection range, a reference protection curve is calculated according to the smoke emission characteristic curve of the wiring harness, the smoke emission characteristic curve of the battery pack copper plate, and the smoke emission characteristic curve of the fuse.

[0027] The target protection curve is constructed based on the preset critical protection offset coefficient, the preset load offset coefficient, the load characteristic curve, and the reference protection curve.

[0028] Optionally, the step of performing a high-voltage operation on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle includes:

[0029] The time percentage coefficient corresponding to the real-time current of the high-voltage circuit is obtained based on the target protection curve corresponding to the second protection range.

[0030] When the time percentage coefficient reaches a preset coefficient threshold, a high-pressure operation is performed on the entire vehicle to protect it from thermal failure.

[0031] Furthermore, to achieve the above objectives, the present invention also proposes a thermal failure protection device, the thermal failure protection device comprising:

[0032] The acquisition module is used to acquire the real-time current of the vehicle's high-voltage circuit.

[0033] The detection module is used to determine whether the vehicle is at risk of thermal failure based on the real-time current of the high-voltage circuit.

[0034] The judgment module is used to determine the target thermal failure protection strategy based on the real-time current of the high-voltage circuit if the vehicle is at risk of thermal failure.

[0035] The control module is used to perform thermal failure protection on the vehicle according to the target thermal failure protection strategy.

[0036] Furthermore, to achieve the above objectives, the present invention also proposes a thermal failure protection device, which includes: a memory, a processor, and a thermal failure protection program stored in the memory and running on the processor, the thermal failure protection program being configured to implement the thermal failure protection method as described above.

[0037] In addition, to achieve the above objectives, the present invention also proposes a storage medium storing a thermal failure protection program, which, when executed by a processor, implements the thermal failure protection method as described above.

[0038] This invention acquires the real-time current of a vehicle's high-voltage circuit; determines whether the vehicle is at risk of thermal failure based on the real-time current of the high-voltage circuit; if the vehicle is at risk of thermal failure, determines a target thermal failure protection strategy based on the real-time current of the high-voltage circuit; and performs thermal failure protection on the vehicle according to the target thermal failure protection strategy. This method enables corresponding thermal failure protection for different high-voltage circuits, providing more comprehensive protection for the high-voltage circuit, improving the high-voltage safety performance of the product, further preventing spontaneous combustion of electric vehicles, and ensuring the safety of users' personal safety and property. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the thermal failure protection device for the hardware operating environment involved in the embodiments of the present invention;

[0040] Figure 2 This is a flowchart illustrating the first embodiment of the thermal failure protection method of the present invention;

[0041] Figure 3 This is a schematic diagram of existing protection in one embodiment of the thermal failure protection method of the present invention;

[0042] Figure 4 This is a flowchart illustrating the second embodiment of the thermal failure protection method of the present invention;

[0043] Figure 5 This is a flowchart illustrating the third embodiment of the thermal failure protection method of the present invention;

[0044] Figure 6 This is a schematic diagram of the target protection curve construction in one embodiment of the thermal failure protection method of the present invention;

[0045] Figure 7 This is a structural block diagram of the first embodiment of the thermal failure protection device of the present invention.

[0046] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0047] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0048] Reference Figure 1 , Figure 1 This is a schematic diagram of the thermal failure protection device structure for the hardware operating environment involved in the embodiments of the present invention.

[0049] like Figure 1 As shown, the thermal failure protection device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0050] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the thermal failure protection device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0051] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a thermal failure protection program.

[0052] exist Figure 1 In the thermal failure protection device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the thermal failure protection device of the present invention can be set in the thermal failure protection device, and the thermal failure protection device calls the thermal failure protection program stored in the memory 1005 through the processor 1001 and executes the thermal failure protection method provided in the embodiment of the present invention.

[0053] This invention provides a thermal failure protection method, referring to... Figure 2 , Figure 2 This is a schematic flowchart of the first embodiment of a thermal failure protection method of the present invention.

[0054] In this embodiment, the thermal failure protection method includes the following steps:

[0055] Step S10: Obtain the real-time current of the vehicle's high-voltage circuit.

[0056] In this embodiment, the executing entity can be the thermal failure protection device, which has functions such as data processing, data communication, and program execution. The thermal failure protection device can be a vehicle controller. Of course, other devices with similar functions can also be used, and this embodiment does not limit this. For ease of explanation, this embodiment uses a thermal failure protection device as an example.

[0057] It should be noted that in recent years, frequent fires and spontaneous combustion incidents involving new energy vehicles have negatively impacted the development of the new energy vehicle industry. More importantly, they threaten the lives and property of customers. Thermal failure design is particularly important in the design of new energy vehicles, involving various high-voltage subsystems. Among them, high-voltage connection components, as an important part of the high-voltage system, need to be designed at three levels: vehicle, system, and component. For example, according to battery characteristics, the lower the SOC, the lower the battery terminal voltage, the lower the battery temperature, and the higher the battery internal resistance. According to I=U / R, U is the battery terminal voltage, R is the battery internal resistance, and I is the real-time current. When the battery SOC is low (low terminal voltage) and the battery temperature is low (high internal resistance), if a short circuit occurs, the real-time current is small. When the current is less than a certain threshold, the fuse blows later than the wiring harness smoke and the relay blows. The fuse cannot protect the high-voltage circuit, which can cause the vehicle to spontaneously combust. Further reference... Figure 3 As shown, Figure 3 Point A in the diagram represents the protection range of the fuse. L1 represents the smoke emission characteristic curve of the battery pack's copper plate, L2 represents the smoke emission characteristic curve of the wiring harness, and L3 represents the smoke emission characteristic curve of the fuse. When the current in the high-voltage circuit is greater than or equal to this current, the fuse can provide high-voltage protection, such as by blowing the fuse to protect the vehicle from thermal failure. However, when the current in the high-voltage circuit is less than the current value corresponding to point A, the fuse blows later than the wiring harness smoke emission and the relay blows. In this case, the fuse cannot protect the high-voltage circuit and will eventually cause the vehicle to spontaneously combust.

[0058] To address the aforementioned technical issues, this embodiment acquires the real-time current of the vehicle's high-voltage circuit; determines whether the vehicle faces a thermal failure risk based on the real-time current of the high-voltage circuit; if the vehicle faces a thermal failure risk, determines a target thermal failure protection strategy based on the real-time current of the high-voltage circuit; and implements thermal failure protection for the vehicle according to the target thermal failure protection strategy. This method enables corresponding thermal failure protection for different high-voltage circuits, providing more comprehensive protection for the high-voltage circuit, improving the high-voltage safety performance of the product, further preventing spontaneous combustion of electric vehicles, and ensuring the safety of users' lives and property. Specifically, this can be achieved as follows.

[0059] In this specific implementation, the present embodiment is aimed at preventing thermal failure of the vehicle. Before performing thermal failure protection on the vehicle, the present embodiment first needs to obtain the real-time current of the vehicle's high-voltage circuit.

[0060] Step S20: Determine whether the vehicle is at risk of thermal failure based on the real-time current of the high-voltage circuit.

[0061] In this embodiment, a first thermal failure protection strategy and a second thermal failure protection strategy are set for thermal failure protection. The first thermal failure protection strategy and the second thermal failure protection strategy correspond to different current ranges. For example, the current range corresponding to the first thermal failure protection strategy can be [i3, ∞), and the current range corresponding to the second thermal failure protection strategy is [i4, i3). When the real-time current of the high-voltage circuit is detected to exceed i4, it can be considered that there is a risk of thermal failure in the high-voltage circuit.

[0062] Step S30: If the vehicle is at risk of thermal failure, determine the target thermal failure protection strategy based on the real-time current of the high-voltage circuit.

[0063] It should be noted that current thermal failure protection methods only rely on fuse blowing to prevent vehicles from spontaneously combusting. However, fuse blowing requires the current to reach a certain threshold. When the current is less than a certain threshold, the fuse cannot protect the high-voltage circuit. In response to this situation, this embodiment sets corresponding thermal failure protection strategies for the real-time current of high-voltage circuits of different sizes, ensuring that even if the real-time current of the high-voltage circuit is less than the protection range of the fuse, thermal failure protection can still be provided for the vehicle.

[0064] Step S40: Perform thermal failure protection on the vehicle according to the target thermal failure protection strategy.

[0065] In practical implementation, after determining the target thermal failure protection strategy, this embodiment can achieve thermal failure protection for the vehicle according to the target failure protection strategy. Specifically, the target thermal failure protection strategy in this embodiment may include a first thermal failure protection strategy and a second thermal failure protection strategy. The first thermal failure protection strategy can be configured to achieve thermal failure protection for the vehicle by blowing a fuse. The second thermal failure protection strategy performs a high-voltage operation on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle. Of course, other methods can also be used to protect the vehicle from thermal failure in this embodiment, and this embodiment does not limit this.

[0066] This embodiment acquires the real-time current of the vehicle's high-voltage circuit; determines whether the vehicle has a risk of thermal failure based on the real-time current of the high-voltage circuit; if the vehicle has a risk of thermal failure, determines a target thermal failure protection strategy based on the real-time current of the high-voltage circuit; and performs thermal failure protection on the vehicle according to the target thermal failure protection strategy. This method can achieve corresponding thermal failure protection for different high-voltage circuits, providing more comprehensive protection for the high-voltage circuit, improving the high-voltage safety performance of the product, further preventing spontaneous combustion of electric vehicles, and ensuring the safety of users' personal safety and property.

[0067] refer to Figure 4 , Figure 4 This is a schematic flowchart of a second embodiment of a thermal failure protection method according to the present invention.

[0068] Based on the first embodiment described above, in the thermal failure protection method of this embodiment, step S30 specifically includes:

[0069] Step S301: When the real-time current of the high-voltage circuit is within the first protection range, the first thermal failure protection strategy is taken as the target thermal failure protection strategy.

[0070] Step S302: When the real-time current of the high-voltage circuit is within the second protection range, the second thermal failure protection strategy is taken as the target thermal failure protection strategy.

[0071] In specific implementation, after obtaining the real-time current of the high-voltage circuit, this embodiment can set corresponding thermal failure protection strategies for different magnitudes of real-time current. Specifically, this embodiment compares the real-time current of the high-voltage circuit with the first protection range and the second protection range. If the real-time current of the high-voltage circuit is within the first protection range, then the first thermal failure protection strategy can be used as the target thermal failure protection strategy. If the real-time current of the high-voltage circuit is within the second protection range, then the second thermal failure protection strategy can be used as the target thermal failure protection strategy. It should be further noted that the lower limit of the first protection range is the upper limit of the second protection range. For example, if the first protection range is [i3, ∞), then the second protection range can be [i4, i3). Figure 3 As shown, the current value corresponding to i3 is also... Figure 3 The current value corresponding to point A in the middle.

[0072] Furthermore, the first protection zone is also... Figure 3Point A can be determined by finding the intersection of multiple curves. Specifically, to obtain an accurate first protection range, this embodiment first needs to obtain the smoke emission characteristic curves of the vehicle's wiring harness, battery pack copper plate, and fuse through simulation. These smoke emission characteristic curves are simulated under various operating conditions, and the final smoke emission characteristic curve is constructed from the data of the most severe extreme operating condition. After obtaining the aforementioned smoke emission characteristic curves of the wiring harness, battery pack copper plate, and fuse, this embodiment can determine the first reference current value based on the wiring harness and fuse smoke emission characteristic curves, and determine the second reference current value based on the battery pack copper plate and fuse smoke emission characteristic curves.

[0073] In an optional embodiment, assuming the smoke emission characteristic curve of the wiring harness is t1(i), the smoke emission characteristic curve of the battery pack copper plate is t2(i), and the smoke emission characteristic curve of the fuse is t3(i), when determining the first reference current value based on the smoke emission characteristic curves of the wiring harness and the fuse, t1(i) can be set to t3(i) to obtain i1, which is the first reference current value. When determining the second reference current value based on the smoke emission characteristic curves of the battery pack copper plate and the fuse, t2(i) can be set to t3(i) to obtain i2, which is the second reference current value. After obtaining the first reference current value i1 and the second reference current value i2, in this embodiment, the maximum value between the first reference current value and the second reference current value can be used as the first target current value, and the first protection range can be obtained by using the first target current value as the lower limit value. For example, if i3 = max{i1,i2}, i3 is the first target current value, and the first protection range can be obtained as [i3, ∞). If the real-time current of the high-voltage circuit is within the first protection range, it means that the real-time current of the high-voltage circuit is greater than i3 at this time.

[0074] In another optional embodiment, when determining the second protection range, the lower limit of the first protection range can be used as the upper limit of the second protection range, for example, i3 can be used as the upper limit of the second protection range. When determining the lower limit of the second protection range, the third reference current value corresponding to the smoke emission characteristic curve of the wiring harness, the fourth reference current value corresponding to the smoke emission characteristic curve of the battery pack copper plate, and the fifth reference current value corresponding to the smoke emission characteristic curve of the fuse can be calculated according to the slope. For example, let dt1(i) / di = k to obtain i1'; let dt2(i) / di = k to obtain i2'; let dt3(i) / di = k to obtain i3', where i1', i2', and i3' are the third reference current value, the fourth reference current value, and the fifth reference current value, respectively, and k is a preset slope, which can be set to a value that tends to infinity. Furthermore, the minimum value among the third, fourth, and fifth reference current values ​​is taken as the second target current value. For example, i4 = min{i1',i2',i3'}, i4 is the second target current value. The second target current value can be used as the lower limit of the second protection range, and the second protection range is [i4, i3). When the real-time current is in [i4, i3), it is considered that the real-time current is within the second protection range.

[0075] This embodiment obtains the smoke emission characteristic curves of the wiring harness, the battery pack copper plate, and the fuse corresponding to the vehicle; determines a first reference current value based on the wiring harness and fuse smoke emission characteristic curves; determines a second reference current value based on the battery pack copper plate and fuse smoke emission characteristic curves; uses the maximum value between the first and second reference current values ​​as a first target current value, and uses the first target current value as a lower limit to obtain a first protection range; and calculates a third reference current value corresponding to the wiring harness smoke emission characteristic curve, a fourth reference current value corresponding to the battery pack copper plate smoke emission characteristic curve, and a fifth reference current value corresponding to the fuse smoke emission curve based on preset curve slopes. The current value; the minimum value among the third, fourth, and fifth reference current values ​​is used as the second target current value, and the first target current value is used as the upper limit and the second target current value as the lower limit to obtain the second protection range. When the real-time current of the high-voltage circuit is within the first protection range, the first thermal failure protection strategy is used as the target thermal failure protection strategy; when the real-time current of the high-voltage circuit is within the second protection range, the second thermal failure protection strategy is used as the target thermal failure protection strategy. By setting a more reasonable and accurate protection range in the above manner, a more reasonable strategy can be used to protect the vehicle from thermal failure, further preventing electric vehicles from spontaneously combusting and ensuring the safety of users' persons and property.

[0076] refer to Figure 5 , Figure 5 This is a flowchart illustrating a third embodiment of a thermal failure protection method according to the present invention.

[0077] Based on the second embodiment described above, a third embodiment of the thermal failure protection method of the present invention is proposed.

[0078] In this embodiment, step S40 specifically includes:

[0079] Step S401: When the target thermal failure protection strategy is the first thermal failure protection strategy, thermal failure protection of the vehicle is achieved by blowing the fuse.

[0080] In specific implementation, when the target thermal failure protection strategy is the first thermal failure protection strategy, it means that the real-time current is within the protection range of the fuse and the fuse can play a protective role. Therefore, when the target thermal failure protection strategy is the first thermal failure protection strategy, thermal failure protection of the vehicle is achieved by fuse blowing in this embodiment.

[0081] Step S402: When the target thermal failure protection strategy is the second thermal failure protection strategy, the vehicle is subjected to a high-voltage operation based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle.

[0082] In practical implementation, when the target thermal failure protection strategy is the second thermal failure protection strategy, it indicates that the real-time current is not within the protection range of the fuse, and the fuse cannot provide protection. In this case, it is necessary to add a control strategy to protect the high-voltage circuit within the range where the fuse cannot provide protection, while also preventing the vehicle from accidentally triggering the protection logic during normal driving conditions. In this embodiment, a high-voltage operation can be performed on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection. Specifically, the real-time current of the high-voltage circuit changes in real time. When the real-time current is within the second protection range, it is necessary to obtain the time proportion coefficient corresponding to each real-time changing current based on the target protection curve, then accumulate them, and when the time proportion coefficient reaches a preset coefficient threshold, a high-voltage operation is performed on the entire vehicle to achieve thermal failure protection. For example, assuming the real-time currents at different times are i5, i6, i7, i8, and i9, the target curve is as follows... Figure 6As shown, based on this curve, the durations corresponding to i5, i6, i7, i8, and i9 can be determined as T5, T6, T7, T8, and T9, respectively. This duration represents the maximum duration that the real-time current can continue at the current value. Assuming that in actual situations, the actual durations of i5, i6, i7, i8, and i9 are t5, t6, t7, t8, and t9, respectively, the time proportion coefficients corresponding to i5, i6, i7, i8, and i9 can be calculated as t5 / T5, t6 / T6, t7 / T7, t8 / T8, and t9 / T9, respectively. The preset coefficient threshold can be set to 1. When the sum of t5 / T5, t6 / T6, t7 / T7, t8 / T8, and t9 / T9 is 1, a high-voltage operation is performed on the entire vehicle to achieve thermal failure protection for the vehicle.

[0083] Furthermore, in constructing the target protection curve, this embodiment requires first obtaining the load characteristic curve; the specific process can be found in [reference needed]. Figure 6 As shown, L1 represents the smoke emission characteristic curve of the battery pack copper plate, L2 represents the smoke emission characteristic curve of the wiring harness, L3 represents the smoke emission characteristic curve of the fuse, L4 represents the load characteristic curve, and L5 represents the target protection curve. A reference protection curve is calculated based on the second protection range, using the smoke emission characteristic curves of the wiring harness, the battery pack copper plate, and the fuse as a benchmark. This means that within the second protection range, [the target protection curve is selected]. Figure 6 The shortest duration of L1, L2, and L3 shown in the diagram is used as the reference protection curve t5(i), i.e., t5(i) = min{t1(i), t2(i), t3(i)}. Finally, the target protection curve is constructed based on the preset critical protection offset coefficient, the preset load offset coefficient, the load characteristic curve, and the reference protection curve. For example, t6(i) = (k1*t5(i) + k2*t4(i)) / 2, where t6(i) represents the target protection curve ( Figure 6 In the diagram, L5), t5(i) is the reference protection curve (not shown in the figure), t4(i) represents the load characteristic curve, k1 is the preset critical protection offset coefficient, k2 is the preset load offset coefficient, and k1+k2=2. The range of i is the second protection range. It should also be noted that existing technologies simulate the vehicle driving condition curve using different methods, and use the simulated vehicle driving condition curve as the protection curve. Figure 6As shown in L5), however, there is no unified standard for simulating the vehicle's driving condition curves, and it is impossible to simulate all conditions. Therefore, using only the simulated extreme condition curves as protection curves carries a high probability of falsely triggering the protection logic, affecting the customer's driving experience, and posing certain risks. For example, in high-speed hill climbing, falsely triggering the protection logic could cause the vehicle to shut down and become unusable. In this embodiment, the vehicle's load characteristic curves are obtained by fitting eight extreme conditions. For example, simulations are performed on eight conditions: NEDC, CLTC, WLTC, high-speed hill climbing, continuous driving at maximum speed, 0-100 km / h acceleration, high-speed lane changing, and high-speed overtaking. The changes in current over time are obtained, and the equivalent heating current in each time period (1S, 5S, 30S, 100S, and so on) is calculated, resulting in eight It curves. Then, the interval with the largest current in each curve is taken and integrated into the It curve for normal vehicle driving conditions, yielding the final... Figure 6 L4 is shown in the diagram.

[0084] This embodiment achieves thermal failure protection for the vehicle by blowing a fuse when the target thermal failure protection strategy is the first thermal failure protection strategy; and achieves thermal failure protection for the vehicle by performing a high-voltage operation on the entire vehicle based on the target protection curve corresponding to the second protection range when the target thermal failure protection strategy is the second thermal failure protection strategy. In this way, corresponding thermal failure protection can be achieved for different high-voltage circuits, which can more comprehensively protect the high-voltage circuit, improve the high-voltage safety performance of the product, further prevent the spontaneous combustion of electric vehicles, and protect the personal and property safety of users.

[0085] Furthermore, this embodiment of the invention also proposes a storage medium storing a thermal failure protection program, which, when executed by a processor, implements the steps of the thermal failure protection method described above.

[0086] Since this storage medium adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0087] Reference Figure 7 , Figure 7 This is a structural block diagram of the first embodiment of the thermal failure protection device of the present invention.

[0088] like Figure 7 As shown, the thermal failure protection device proposed in this embodiment of the invention includes:

[0089] The acquisition module 10 is used to acquire the real-time current of the vehicle's high-voltage circuit.

[0090] The detection module 20 is used to determine whether the vehicle has a risk of thermal failure based on the real-time current of the high-voltage circuit.

[0091] The judgment module 30 is used to determine the target thermal failure protection strategy based on the real-time current of the high-voltage circuit if the vehicle has a risk of thermal failure.

[0092] The control module 40 is used to perform thermal failure protection on the vehicle according to the target thermal failure protection strategy.

[0093] This embodiment acquires the real-time current of the vehicle's high-voltage circuit; determines whether the vehicle has a risk of thermal failure based on the real-time current of the high-voltage circuit; if the vehicle has a risk of thermal failure, determines a target thermal failure protection strategy based on the real-time current of the high-voltage circuit; and performs thermal failure protection on the vehicle according to the target thermal failure protection strategy. This method can achieve corresponding thermal failure protection for different high-voltage circuits, providing more comprehensive protection for the high-voltage circuit, improving the high-voltage safety performance of the product, further preventing spontaneous combustion of electric vehicles, and ensuring the safety of users' personal safety and property.

[0094] In one embodiment, the judgment mode 30 is further configured to, when the real-time current of the high-voltage circuit is within the first protection range, use the first thermal failure protection strategy as the target thermal failure protection strategy; and when the real-time current of the high-voltage circuit is within the second protection range, use the second thermal failure protection strategy as the target thermal failure protection strategy, wherein the lower limit of the first protection range is the upper limit of the second protection range.

[0095] In one embodiment, the thermal failure protection device further includes a computing module;

[0096] The calculation module is used to acquire the smoke emission characteristic curves of the wiring harness, the battery pack copper plate, and the fuse corresponding to the vehicle; determine a first reference current value based on the smoke emission characteristic curves of the wiring harness and the fuse; determine a second reference current value based on the smoke emission characteristic curves of the battery pack copper plate and the fuse; and obtain a first protection range by using the maximum value between the first and second reference current values ​​as the first target current value and using the first target current value as the lower limit value.

[0097] In one embodiment, the calculation module is further configured to calculate, according to the preset curve slope, a third reference current value corresponding to the smoke emission characteristic curve of the wiring harness, a fourth reference current value corresponding to the smoke emission characteristic curve of the battery pack copper plate, and a fifth reference current value corresponding to the smoke emission characteristic curve of the fuse; and to obtain a second protection range by using the minimum value among the third reference current value, the fourth reference current value, and the fifth reference current value as a second target current value, and by using the first target current value as an upper limit value and the second target current value as a lower limit value.

[0098] In one embodiment, the control module 40 is further configured to perform thermal failure protection on the vehicle by blowing a fuse when the target thermal failure protection strategy is a first thermal failure protection strategy; and to perform thermal failure protection on the vehicle by performing a high-voltage operation on the whole vehicle based on the target protection curve corresponding to the second protection range when the target thermal failure protection strategy is a second thermal failure protection strategy.

[0099] In one embodiment, the thermal failure protection device further includes a construction module;

[0100] The construction module is used to obtain the load characteristic curve corresponding to the vehicle; calculate a reference protection curve based on the second protection range according to the smoke emission characteristic curve of the wiring harness, the smoke emission characteristic curve of the battery pack copper plate, and the smoke emission characteristic curve of the fuse; and construct a target protection curve according to the preset critical protection offset coefficient, the preset load offset coefficient, the load characteristic curve, and the reference protection curve.

[0101] In one embodiment, the control module 40 is further configured to obtain the time proportion coefficient corresponding to the real-time current of the high-voltage circuit based on the target protection curve corresponding to the second protection range; when the time proportion coefficient reaches a preset coefficient threshold, perform a high-voltage operation on the whole vehicle to achieve thermal failure protection for the vehicle.

[0102] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solutions of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0103] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0104] In addition, for technical details not described in detail in this embodiment, please refer to the thermal failure protection method provided in any embodiment of the present invention, which will not be repeated here.

[0105] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0106] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0107] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0108] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

[0109] It should be understood that although the steps in the flowcharts of this application's embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

Claims

1. A method of thermal runaway protection, the method comprising: The thermal failure protection method includes: Obtain the real-time current of the vehicle's high-voltage circuit; The risk of thermal failure in the vehicle is determined based on the real-time current of the high-voltage circuit. If the vehicle is at risk of thermal failure, the target thermal failure protection strategy is determined based on the real-time current of the high-voltage circuit. Thermal failure protection is performed on the vehicle according to the target thermal failure protection strategy; The step of determining the target thermal failure protection strategy based on the real-time current of the high-voltage circuit includes: When the real-time current of the high-voltage circuit is within the first protection range, the first thermal failure protection strategy is taken as the target thermal failure protection strategy. When the real-time current of the high-voltage circuit is within the second protection range, the second thermal failure protection strategy is used as the target thermal failure protection strategy, and the lower limit of the first protection range is the upper limit of the second protection range. Before setting the first thermal failure protection strategy as the target thermal failure protection strategy when the real-time current of the high-voltage circuit is within the first protection range, the method further includes: The smoke emission characteristic curves of the wiring harness, the copper plate of the battery pack, and the fuse corresponding to the vehicle are obtained. A first reference current value is determined based on the smoke emission characteristic curves of the wiring harness and the fuse. A second reference current value is determined based on the smoke emission characteristic curves of the copper plate of the battery pack and the fuse. The maximum value between the first reference current value and the second reference current value is taken as the first target current value, and the first target current value is taken as the lower limit value to obtain the first protection range. Before using the second thermal failure protection strategy as the target thermal failure protection strategy when the real-time current of the high-voltage circuit is within the second protection range, the method further includes: The third reference current value corresponding to the smoke emission characteristic curve of the wiring harness, the fourth reference current value corresponding to the smoke emission characteristic curve of the battery pack copper plate, and the fifth reference current value corresponding to the smoke emission characteristic curve of the fuse are calculated according to the preset curve slope. The minimum value among the third reference current value, the fourth reference current value, and the fifth reference current value is used as the second target current value. The second protection range is obtained by using the first target current value as the upper limit value and the second target current value as the lower limit value.

2. The thermal failure prevention method of claim 1, wherein, The step of performing thermal failure protection on the vehicle according to the target thermal failure protection strategy includes: When the target thermal failure protection strategy is the first thermal failure protection strategy, thermal failure protection of the vehicle is achieved by blowing the fuse. When the target thermal failure protection strategy is the second thermal failure protection strategy, the vehicle is subjected to a high-pressure operation based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle.

3. The thermal failure prevention method of claim 2, wherein, Before performing high-pressure operation on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle, the method further includes: Obtain the load characteristic curve corresponding to the vehicle; Based on the second protection range, a reference protection curve is calculated according to the smoke emission characteristic curve of the wiring harness, the smoke emission characteristic curve of the battery pack copper plate, and the smoke emission characteristic curve of the fuse. The target protection curve is constructed based on the preset critical protection offset coefficient, the preset load offset coefficient, the load characteristic curve, and the reference protection curve.

4. The thermal failure protection method as described in claim 2, characterized in that, The method of performing a high-voltage operation on the entire vehicle based on the target protection curve corresponding to the second protection range to achieve thermal failure protection for the vehicle includes: The time percentage coefficient corresponding to the real-time current of the high-voltage circuit is obtained based on the target protection curve corresponding to the second protection range. When the time percentage coefficient reaches a preset coefficient threshold, a high-pressure operation is performed on the entire vehicle to protect it from thermal failure.

5. A thermal failure protection device, characterized in that, The thermal failure protection device includes: The acquisition module is used to acquire the real-time current of the vehicle's high-voltage circuit. The detection module is used to determine whether the vehicle is at risk of thermal failure based on the real-time current of the high-voltage circuit. The judgment module is used to determine the target thermal failure protection strategy based on the real-time current of the high-voltage circuit if the vehicle is at risk of thermal failure. The control module is used to perform thermal failure protection on the vehicle according to the target thermal failure protection strategy; The judgment module is also used to take the first thermal failure protection strategy as the target thermal failure protection strategy when the real-time current of the high-voltage circuit is within the first protection range. When the real-time current of the high-voltage circuit is within the second protection range, the second thermal failure protection strategy is used as the target thermal failure protection strategy, and the lower limit of the first protection range is the upper limit of the second protection range. The judgment module is also used to obtain the smoke emission characteristic curve of the wiring harness, the smoke emission characteristic curve of the battery pack bronze plate, and the smoke emission characteristic curve of the fuse corresponding to the vehicle. The first reference current value is determined based on the smoke emission characteristic curve of the wiring harness and the smoke emission characteristic curve of the fuse. The second reference current value is determined based on the smoke emission characteristic curve of the battery pack copper plate and the smoke emission characteristic curve of the fuse. The first protection range is obtained by taking the maximum value between the first reference current value and the second reference current value as the first target current value and taking the first target current value as the lower limit value. The judgment module is also used to calculate the third reference current value corresponding to the smoke emission characteristic curve of the wire harness, the fourth reference current value corresponding to the smoke emission characteristic curve of the battery pack copper plate, and the fifth reference current value corresponding to the smoke emission characteristic curve of the fuse according to the preset curve slope. The minimum value among the third reference current value, the fourth reference current value, and the fifth reference current value is used as the second target current value, and the first target current value is used as the upper limit value and the second target current value is used as the lower limit value to obtain the second protection range.

6. A thermal failure protection device, characterized in that, The thermal failure protection device includes: a memory, a processor, and a thermal failure protection program stored on the memory and running on the processor, the thermal failure protection program being configured to implement the thermal failure protection method as described in any one of claims 1 to 4.

7. A storage medium, characterized in that, The storage medium stores a thermal failure protection program, which, when executed by a processor, implements the thermal failure protection method as described in any one of claims 1 to 4.

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