High-voltage safety control system and method for electric vehicles

Abstract

This invention relates to a high-voltage safety control system for electric vehicles, comprising a battery box, a collision displacement sensor, battery branches, battery modules, excitation fuses, a distribution box, a main positive contactor, a main negative contactor, an emergency disconnect switch, a BMS controller, a CPDU central power distribution control, high-voltage loads, and instruments. This invention also relates to a high-voltage safety control method for electric vehicles, comprising the steps of: assessing the collision hazard level; assessing the severity of battery pack damage; executing a high-voltage positive and negative output disconnect control process; and executing an internal disconnect control process within the battery box. This invention accurately judges and appropriately responds to collision states in commercial vehicles with unique battery box arrangements such as under-mounted, side-mounted, and rear-mounted configurations; improves safety in abnormal situations; and enables rapid disconnection of the high-voltage circuit in the event of a battery collision or other abnormal conditions, ensuring the safety of occupants and the vehicle.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle control technology, and more specifically to a high-voltage safety control system and method for electric vehicles. Background Technology

[0002] As the energy storage unit of electric vehicles, the power battery system in electric vehicles has poorer high-voltage safety compared to traditional fuel vehicles. Especially during a vehicle collision, if the power battery is squeezed or deformed by impact, there is a risk of fire and explosion. Although the power battery is protected by the battery frame in commercial vehicles, there is still a significant risk, so it is necessary to disconnect the entire high-voltage circuit in time. Currently, the main methods in the industry for disconnecting the high-voltage circuit in a collision are to use the battery management system (BMS) to disconnect the high-voltage relay in the battery system or to use an excitation fuse connected in series in the high-voltage circuit of the battery pack that can be instantly detonated after receiving the airbag deployment signal.

[0003] The shortcomings of existing technology are:

[0004] 1. Due to the current technology's method of cutting off high voltage during airbag deployment, there are situations where vehicles are not equipped with airbags. Furthermore, the different battery placement methods used in commercial vehicles, such as rear-mounted and bottom-mounted configurations, make it impossible to accurately assess the impact of collisions involving different battery locations, posing a risk of false high-voltage collision triggering.

[0005] 2. Existing technologies have the risk of failure due to high-voltage relay sticking and inability to cut off the circuit. There is also a lack of methods for quickly cutting off the high-voltage circuit in situations such as software failure, inability to cut off the high-voltage circuit, or non-collision situations such as battery fire. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a high-voltage safety control system and method for electric vehicles. Its purpose is to accurately judge and reasonably respond to collision states under the unique battery pack arrangements of commercial vehicles, such as those with bottom-mounted, side-mounted, or rear-mounted configurations; improve safety in abnormal situations; and achieve rapid disconnection of the high-voltage circuit in the event of a battery collision or other abnormal conditions, thereby ensuring the safety of occupants and the vehicle.

[0007] To solve the above problems, the technical solution provided by the present invention is as follows:

[0008] A high-voltage safety control system for an electric vehicle includes a battery box, a collision displacement sensor, battery branches, battery modules, excitation fuses, a distribution box, a main positive contactor, a main negative contactor, an emergency stop switch, a BMS controller, a CPDU central power distribution control, a high-voltage load, and instruments; wherein:

[0009] The collision displacement sensor is used to monitor the collision status of the battery box; the collision displacement sensor is mounted on the battery frame arranged around the battery box; the collision displacement sensor is connected to the CPDU central power distribution control.

[0010] The battery branch includes the battery module and the excitation fuse; the battery module connects to the high-voltage contact of the excitation fuse to enable the circuit of the battery branch; the control terminal of the excitation fuse is connected to the BMS controller.

[0011] One of the two control terminals of the main positive contactor is connected to the CPDU central power distribution control, and the other terminal is connected to the emergency disconnect switch.

[0012] The control terminal of the main negative contactor is connected to the central power distribution control of the CPDU.

[0013] Preferably, the battery branch includes a first battery branch and a second battery branch; the excitation fuse includes a first excitation fuse and a second excitation fuse; wherein:

[0014] The battery module in the first battery branch is connected to the high-voltage contact of the first excitation fuse to connect the circuit of the first battery branch; the control terminal of the first excitation fuse is connected to the BMS controller.

[0015] The battery module in the second battery branch is connected to the high-voltage contact of the second excitation fuse to connect the circuit of the second battery branch; the control terminal of the second excitation fuse is connected to the BMS controller.

[0016] The collision displacement sensor includes a first collision displacement sensor and a second collision displacement sensor;

[0017] The emergency cut-off switch is a dual-contact redundant switch and is equipped with a locking mechanism to prevent accidental triggering.

[0018] A high-voltage safety control method for electric vehicles utilizing a high-voltage safety control system for electric vehicles includes the following steps:

[0019] S100. The collision hazard level is assessed.

[0020] S200. Assess the severity of battery pack damage;

[0021] S300. Executes the high-voltage positive and negative output cut-off control process;

[0022] S400. Execute the internal disconnection control procedure of the battery box.

[0023] Preferably, S100 specifically includes the following steps:

[0024] S110. The CPDU central power distribution control collects the deformation displacement from the collision displacement sensor;

[0025] S120. Based on the deformation displacement, obtain the collision deformation displacement level;

[0026] S130. Obtain the impact degree of the collision position;

[0027] S140. Substitute the collision deformation displacement level and the collision position influence degree into the collision hazard level table; then look up the table to obtain the collision hazard degree;

[0028] The collision hazard level table is an orthogonal matrix formed by the collision deformation displacement level and the collision position influence degree;

[0029] The collision deformation displacement levels are arranged in ascending order of severity and are divided into L0, L1, L2, and L3 levels; where L0 indicates no impact.

[0030] The impact of the collision location is arranged in ascending order of severity, and is divided into P1, P2, and P3 levels; where P1 level indicates that the collision location is far from the cockpit; P2 level indicates that the collision location is at a medium distance; and P3 level indicates that the collision location is close to the cockpit.

[0031] The collision hazard levels are arranged in ascending order of severity and are divided into S0, S1, S2, and S3 levels.

[0032] Preferably, S120 specifically includes the following steps:

[0033] S121. The deformation displacement is calculated to obtain a deformation correction amount; the deformation correction amount is expressed by the following formula:

[0034] ΔL=η*L t -L i

[0035] Where: ΔL is the deformation correction amount; η is the safety correction coefficient, which is preset manually based on the road conditions under which the vehicle is operating; L t The amount of deformation displacement at the location of the impact displacement sensor is used to generate the deformation caused by the impact; L i The deformation displacement of the collision displacement sensor at the initial position;

[0036] S122. The deformation correction amount is compared with the manually preset collision deformation displacement level threshold range to obtain the corresponding collision deformation displacement level.

[0037] Preferably, S130 specifically includes the following steps:

[0038] S131. The position of the battery pack near the edge of the cockpit is obtained;

[0039] S132. The position of the driver's seat is obtained;

[0040] S133. Measure the straight-line distance between the position of the battery pack near the edge of the cockpit and the position of the driver's seat;

[0041] S134. Compare the straight-line distance between the position of the battery pack near the edge of the cockpit obtained in S133 and the position of the driver's seat with a manually preset collision position influence threshold range to obtain the corresponding collision position influence.

[0042] Preferably, S200 specifically includes the following steps:

[0043] S210. Obtain the collision hazard level obtained in S100;

[0044] S220. Obtain battery temperature and insulation fault status;

[0045] S230. Based on the collision hazard level, the battery temperature, and the insulation fault condition, the initial severity of the battery pack collision is determined comprehensively.

[0046] S240. By collecting information on insulation failure status and battery pack cell temperature rise through the battery's BMS controller, the confidence level of the initial severity assessment of the battery pack collision is corrected to obtain the corrected severity of the battery pack damage.

[0047] The initial severity of the battery pack collision is arranged in ascending order of severity, and is divided into S0, S1, S2 and S3 levels.

[0048] The severity of the battery pack damage is arranged in ascending order of severity, and is divided into M0, M1, M2 and M3 levels;

[0049] The initial severity of the battery pack collision at the same level is the same as that represented by the collision hazard level.

[0050] Preferably, the high-voltage positive and negative output cut-off control process includes M1 high-voltage positive and negative output cut-off control sub-process, M2 high-voltage positive and negative output cut-off control sub-process, and M3 high-voltage positive and negative output cut-off control sub-process.

[0051] The S300 specifically includes the following steps:

[0052] S310. Based on the corrected severity of damage to the battery pack, perform the following operations:

[0053] If the severity of the battery pack damage after correction is level M1, then execute the M1 high voltage positive and negative pole output cut-off control sub-process;

[0054] If the severity of the battery pack damage after correction is M2, then the M2 high voltage positive and negative pole output cut-off control sub-process is executed;

[0055] If the severity of the battery pack damage after correction is M3, then the M3 high voltage positive and negative pole output cut-off control sub-process is executed;

[0056] The M1 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps:

[0057] S310a. The CPDU central power distribution control obtains fault information from the BMS controller; then performs the following operations based on the fault information:

[0058] If the fault information is empty, the instrument panel will send the string "The vehicle's battery box has been hit, affecting safety. Please have it repaired as soon as possible".

[0059] The M2 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps:

[0060] S310b. The CPDU central power distribution control performs a rapid unloading operation on high-voltage loads, specifically including the following steps:

[0061] S311b. The CPDU central power distribution control sets the target drive torque of the motor to 0 Nm;

[0062] S312b. The CPDU central power distribution control controls the electric air compressor, electric air conditioner, and DC-DC converter to stop working;

[0063] S313b. Collects high-voltage circuit current;

[0064] S314b. Compare the high-voltage circuit current with a manually preset high-voltage circuit current threshold, and then perform the following operations based on the comparison result:

[0065] If the high-voltage circuit current is not lower than the high-voltage circuit current threshold, then return and execute S313b again;

[0066] If the high-voltage circuit current is lower than the high-voltage circuit current threshold, then the main negative contactor is controlled to disconnect the negative contactor in sequence, and then the main positive contactor is controlled to disconnect the positive contactor.

[0067] S315b. Safety warnings are given to personnel in the driver's cab and outside the vehicle via the aforementioned instruments and buzzer;

[0068] The M3 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps:

[0069] S310c. The torque of the CPDU central power distribution control for controlling high-power, high-voltage loads is 0.

[0070] S311c. Sequentially control the main negative contactor to disconnect the negative contactor, and then control the main positive contactor to disconnect the positive contactor;

[0071] S312c. Safety warnings are given to people in the driver's cab and outside the vehicle via the instruments and buzzer.

[0072] Preferably, S400 specifically includes the following steps:

[0073] S410. Check the execution result of the M2 high-voltage positive and negative output cutoff control sub-process or the M3 high-voltage positive and negative output cutoff control sub-process; then, based on the check result, perform the following operations:

[0074] If the execution result of the M2 high voltage positive and negative pole output cut-off control sub-process or the M3 high voltage positive and negative pole output cut-off control sub-process is normal cut-off, then the current high voltage safety control ends.

[0075] If the execution result of the M2 high voltage positive and negative pole output cut-off control sub-process or the M3 high voltage positive and negative pole output cut-off control sub-process is not normal cut-off, or the contactor is burned out, then execute S420.

[0076] S420. The CPDU central power distribution control requests the BMS controller to activate the control signal of the first excitation fuse in the first battery branch, thereby blowing the internal fuse of the battery box;

[0077] The CPDU central power distribution control requests the BMS controller to activate the control signal of the second excitation fuse in the second battery branch, thereby blowing the internal fuse of the battery box.

[0078] Preferably, it further includes an emergency high-voltage circuit disconnection process; the emergency high-voltage circuit disconnection process specifically includes the following steps:

[0079] S500. Control the emergency disconnect switch to cut off high voltage control; specifically including the following steps:

[0080] S501. The main positive contactor is directly disconnected from the circuit;

[0081] S510. Disconnection Status - Safety Status Protection; specifically includes the following steps:

[0082] S511. When the CPDU central power distribution control detects that the contacts of the emergency disconnect switch are open, the emergency steering is initiated;

[0083] S512. Safety warnings are given to people in the driver's cab and outside the vehicle through the instruments and buzzer.

[0084] Compared with the prior art, the present invention has the following advantages:

[0085] 1. Because the present invention uses different cutting methods based on collision hazard classification, it is particularly effective in accurately judging and reasonably responding to collision conditions under unique battery pack arrangements such as those on the bottom, side, and rear of commercial vehicles.

[0086] 2. Because this invention uses a safe and reliable dual-contact emergency disconnect switch to manually disconnect the high-voltage circuit in abnormal situations, it improves safety in abnormal situations;

[0087] 3. This invention enables the rapid disconnection of the high-voltage circuit in the event of a battery collision or other abnormal conditions, ensuring the safety of occupants and the vehicle. Attached Figure Description

[0088] Figure 1 This is a schematic diagram of the system structure according to a specific embodiment of the present invention.

[0089] Wherein: KM1. Main positive contactor, KM2. Main negative contactor, FU1. First excitation fuse, FU2. Second excitation fuse, crash1. First collision displacement sensor, crash2. Second collision displacement sensor, SW1. Emergency cut-off switch. Detailed Implementation

[0090] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0091] like Figure 1 As shown, a high-voltage safety control system for an electric vehicle includes a battery box, a collision displacement sensor, battery branches, battery modules, excitation fuses, a distribution box, a main positive contactor KM1, a main negative contactor KM2, an emergency disconnect switch SW1, a BMS controller, a CPDU central power distribution control, a high-voltage load, and instruments; wherein:

[0092] The collision displacement sensor is used to monitor the collision status of the battery box; the collision displacement sensor is mounted on the battery frame arranged around the outer surface of the battery box; the collision displacement sensor is connected to the CPDU central power distribution control.

[0093] In this specific embodiment, collision displacement sensors of the battery frame are arranged around the battery box to measure the displacement deformation during the collision process, and the collision situation of the vehicle is confirmed by the deformation.

[0094] In this specific embodiment, the collision displacement sensor is arranged according to the battery installation method (such as bottom placement, side mounting, rear mounting) to locate the exposed points on the periphery of the battery box.

[0095] The battery branch includes a battery module and an excitation fuse; the battery module connects to the high-voltage contacts of the excitation fuse to enable the circuit of the battery branch; the control terminal of the excitation fuse is connected to the BMS controller.

[0096] One of the two control terminals of the main positive contactor KM1 is connected to the CPDU central power distribution control, and the other terminal is connected to the emergency disconnect switch SW1.

[0097] The control terminal of the main negative contactor KM2 is connected to the CPDU central power distribution control.

[0098] It should be noted that the main negative contactor KM2 enables the rapid disconnection of the negative circuit.

[0099] In this specific embodiment, the battery branch includes a first battery branch and a second battery branch; the excitation fuse includes a first excitation fuse FU1 and a second excitation fuse FU2; wherein:

[0100] The battery module in the first battery branch is connected to the high-voltage contact of the first excitation fuse FU1 to connect the circuit of the first battery branch; the control terminal of the first excitation fuse FU1 is connected to the BMS controller.

[0101] It should be noted that the first excitation fuse FU1 achieves excitation-induced fuse breaking.

[0102] The battery module in the second battery branch is connected to the high-voltage contact of the second excitation fuse FU2 to connect the circuit of the second battery branch; the control terminal of the second excitation fuse FU2 is connected to the BMS controller.

[0103] It should be noted that the second excitation fuse FU2 achieves excitation-induced fuse breaking.

[0104] The collision displacement sensor includes a first collision displacement sensor crash1 and a second collision displacement sensor crash2.

[0105] The emergency disconnect switch SW1 is a dual-contact redundant switch with a locking mechanism to prevent accidental triggering.

[0106] A high-voltage safety control method for electric vehicles utilizing a high-voltage safety control system for electric vehicles includes the following steps:

[0107] S100. Assess the collision hazard level.

[0108] In this specific embodiment, the collision hazard level is determined based on the vehicle's collision situation and battery pack information.

[0109] In this specific embodiment, S100 specifically includes the following steps:

[0110] The S110.CPDU central power distribution control collects deformation displacement data from collision displacement sensors.

[0111] In this specific embodiment, the collision displacement sensor includes a first collision displacement sensor crash1 and a second collision displacement sensor crash2; the first collision displacement sensor crash1 and the second collision displacement sensor crash2 are two displacement sensors at the same position on the battery box 1 (single battery box); in the configuration of multiple boxes, the number of collision sensors needs to be arranged according to the actual installation position of the battery box in order to meet the accuracy of detection.

[0112] In this specific embodiment, the CPDU central power distribution control collects the displacement changes of the first collision displacement sensor crash1 and the second collision displacement sensor crash2 to determine the state of a collision.

[0113] S120. Obtain the collision deformation displacement level based on the deformation displacement amount;

[0114] In this specific embodiment, S120 specifically includes the following steps:

[0115] S121. Deformation displacement, calculated to obtain the deformation correction amount; the deformation correction amount is expressed by the following formula:

[0116] ΔL=η*L t -L i

[0117] Where: ΔL is the deformation correction amount; η is the safety correction coefficient, which is preset manually based on the road conditions under which the vehicle is operating; L t To generate the deformation displacement at the location of the impact displacement sensor; L i This represents the deformation displacement of the collision displacement sensor at its initial position.

[0118] S122. Compare the deformation correction amount with the manually preset collision deformation displacement level threshold range to obtain the corresponding collision deformation displacement level.

[0119] In this specific embodiment, the threshold range for collision deformation displacement level is represented by δ, specifically:

[0120] When ΔL > δ, a collision of the corresponding level is determined to have occurred.

[0121] In this specific embodiment, L0 to L3 correspond to δ0mm, 2mm, 5mm, and 10mm, respectively.

[0122] In this specific embodiment, η is calibrated and selected according to the road conditions on which the vehicle is operating, such as η = 1.02 for gravel road surface and η = 1.00 for paved road surface.

[0123] S130. Obtain the impact of the collision position.

[0124] In this specific embodiment, S130 specifically includes the following steps:

[0125] S131. The position of the battery pack near the edge of the cockpit is obtained.

[0126] S132. The position of the driver's seat is obtained.

[0127] S133. Measure the straight-line distance P between the position of the battery pack near the edge of the cockpit and the position H of the driver's seat.

[0128] S134. Compare the straight-line distance between the position of the battery pack near the edge of the cockpit obtained in S133 and the position of the driver's seat with the manually preset collision position influence threshold range to obtain the corresponding collision position influence.

[0129] S140. Substitute the collision deformation displacement level and the impact degree of the collision location into the collision hazard level table; then look up the table to obtain the collision hazard degree.

[0130] In this specific embodiment, as shown in Table 1, it is an example of a collision hazard level table, which is an orthogonal matrix formed by the collision deformation displacement level and the impact degree of the collision position. In application, collision hazard assessment is performed for different collision deformations.

[0131] Table 1. Example of Collision Hazard Level Table

[0132]

[0133] The collision deformation displacement levels are arranged in ascending order of severity, and are divided into L0, L1, L2, and L3 levels; when the collision deformation displacement level is L0, it indicates that there is no impact.

[0134] The impact of the collision location is ranked in ascending order of severity, and is divided into P1, P2, and P3 levels. A P1 level collision location impact indicates that the vehicle is far from the cockpit; a P2 level collision location impact indicates that the vehicle is at medium distance; and a P3 level collision location impact indicates that the vehicle is close to the cockpit.

[0135] In this specific embodiment, the example vehicle is a pure electric tractor. When the straight-line distance P > 4m, the impact of the collision position is P1; when the straight-line distance 4 ≥ P > 2.5m, the impact of the collision position is P2; and when the straight-line distance P < 2.5m, the impact of the collision position is P3.

[0136] Collision hazard levels are ranked in ascending order of severity, and are divided into S0, S1, S2, and S3 levels.

[0137] S200. Assess the severity of battery pack damage.

[0138] In this specific embodiment, S200 specifically includes the following steps:

[0139] S210. Obtain the collision hazard level obtained in S100.

[0140] S220. Obtain battery temperature and insulation fault status.

[0141] S230. The initial severity of the battery pack collision is determined by comprehensively considering the collision hazard level, battery temperature, and insulation fault condition.

[0142] S240. By collecting information on insulation failure status and battery pack cell temperature rise through the battery's BMS controller, the confidence level of the initial severity assessment of the battery pack collision is corrected to obtain the corrected severity of battery pack damage.

[0143] As shown in Table 2, in this specific embodiment, the correction method is to downgrade the severity of battery pack damage in the above steps if a collision occurs but there is no potential battery pack damage hazard within a set time.

[0144] Table 2. Sample Table of Confidence Level Correction for Initial Severity Assessment of Battery Pack Collision

[0145]

[0146]

[0147] The initial severity of the battery pack collision is arranged in ascending order of severity, and is divided into S0, S1, S2 and S3 levels.

[0148] Battery pack damage severity is ranked in ascending order of severity, and divided into M0, M1, M2, and M3 levels.

[0149] The initial severity and collision hazard levels of battery packs of the same class represent the same content.

[0150] S300. Executes the high voltage positive and negative output cut-off control process.

[0151] In this specific embodiment, excitation fuses are installed in the battery modules of different battery branches inside the battery box to achieve internal disconnection of the battery box.

[0152] In this specific embodiment, the high voltage positive and negative output cut-off control process includes the M1 high voltage positive and negative output cut-off control sub-process, the M2 high voltage positive and negative output cut-off control sub-process, and the M3 high voltage positive and negative output cut-off control sub-process.

[0153] In this specific embodiment, the main positive and main negative contactors KM2 output by the battery box are controlled contactors, which can achieve rapid disconnection in abnormal situations.

[0154] The S300 specifically includes the following steps:

[0155] S310. Based on the corrected severity of battery pack damage, perform the following actions:

[0156] If the severity of the repaired battery pack damage is M1, then execute the M1 high-voltage positive and negative pole output cutoff control sub-process.

[0157] If the severity of the corrected battery pack damage is M2, then execute the M2 high-voltage positive and negative pole output cut-off control sub-process.

[0158] If the severity of the repaired battery pack damage is M3, then execute the M3 high voltage positive and negative pole output cut-off control sub-process.

[0159] The M1 high-voltage positive and negative output cutoff control sub-process specifically includes the following steps:

[0160] The S310a.CPDU central power distribution control obtains fault information from the BMS controller; then, based on the fault information, it performs the following operations:

[0161] If the fault information is empty, the instrument panel will display the string "The vehicle's battery box has been impacted, affecting safety. Please have it inspected as soon as possible."

[0162] It should be noted that the high voltage cut-off action is not required in the M1 high voltage positive and negative output cut-off control sub-process; it is sufficient to inform the driver.

[0163] The M2 high-voltage positive and negative output cutoff control sub-process specifically includes the following steps:

[0164] The S310b.CPDU central power distribution control performs a rapid unloading operation on high-voltage loads, specifically including the following steps:

[0165] The S311b.CPDU central power distribution control sets the target drive torque of the motor to 0 Nm.

[0166] The S312b.CPDU central power distribution control system stops the electric air compressor, electric air conditioner, and DC-DC converter.

[0167] S313b. Collects high-voltage circuit current.

[0168] S314b. Compare the high-voltage circuit current with a manually preset high-voltage circuit current threshold, and then perform the following operations based on the comparison result:

[0169] If the high-voltage circuit current is not lower than the high-voltage circuit current threshold, return and execute S313b again.

[0170] If the high-voltage circuit current is lower than the high-voltage circuit current threshold, then the main negative contactor KM2 is controlled to disconnect the negative contactor in sequence, and then the main positive contactor KM1 is controlled to disconnect the positive contactor.

[0171] It should be noted that the function of S313b to S314b is to prevent the high-voltage contactor from sticking during the disconnection process. Before disconnecting the contactor, it is necessary to determine that the high-voltage circuit current is less than the high-voltage circuit current threshold I.

[0172] In this specific embodiment, I = 5A.

[0173] S315b. Safety warnings are given to people in the cab and outside the vehicle via instruments and buzzers.

[0174] The M3 high-voltage positive and negative output cutoff control sub-process specifically includes the following steps:

[0175] The torque of the S310c.CPDU central power distribution control for high-power, high-voltage loads is 0.

[0176] In this specific embodiment, the high-power, high-voltage load is a drive motor.

[0177] S311c. Sequentially control the main negative contactor KM2 to disconnect the negative contactor, and then control the main positive contactor KM1 to disconnect the positive contactor.

[0178] S312c. Safety warnings are given to people in the driver's cab and outside the vehicle via instruments and buzzers.

[0179] S400. Execute the internal disconnection control procedure of the battery box.

[0180] In this specific embodiment, S400 specifically includes the following steps:

[0181] S410. Check the execution result of the M2 high-voltage positive and negative output cutoff control sub-process or the M3 high-voltage positive and negative output cutoff control sub-process; then, based on the check result, perform the following operations:

[0182] If the execution result of the M2 high-voltage positive and negative pole output cut-off control sub-process or the M3 high-voltage positive and negative pole output cut-off control sub-process is a normal cut-off, then the current high-voltage safety control ends.

[0183] If the execution result of the M2 high voltage positive and negative output cut-off control sub-process or the M3 high voltage positive and negative output cut-off control sub-process is not a normal cut-off, or the contactor is burned out, then execute S420.

[0184] S420.CPDU central power distribution control requests the BMS controller to excite the control signal of the first excitation fuse FU1 in the first battery branch, and blow the internal fuse of the battery box.

[0185] The CPDU central power distribution control requests the BMS controller to excite the control signal of the second excitation fuse FU2 in the second battery branch, thus blowing the internal fuse of the battery box.

[0186] This specific embodiment also includes an emergency high-voltage circuit disconnection process.

[0187] In this specific embodiment, a double-contact high-voltage emergency cut-off switch SW1 is installed at the top of the cab to achieve rapid cut-off in abnormal situations.

[0188] The emergency high-voltage circuit disconnection procedure specifically includes the following steps:

[0189] S500. Controls the emergency disconnect switch SW1 to disconnect the high-voltage control; specifically includes the following steps:

[0190] S501. The main positive contactor KM1 is directly disconnected from the circuit.

[0191] It should be noted that the principle of S500 to S501 is as follows: the emergency disconnect switch SW1 is a normally closed switch with two contacts connected in parallel. When the emergency disconnect switch SW1 is triggered, since the emergency disconnect switch SW1 directly controls the power supply of the control terminal of the main positive contactor KM1, the main positive contactor KM1 is directly disconnected in the circuit, thereby realizing the disconnection of the high voltage positive output.

[0192] S510. Disconnection Status - Safety Status Protection; specifically includes the following steps:

[0193] S511. When the CPDU central power distribution control detects that the contacts of the emergency disconnect switch SW1 are open, the emergency diversion is initiated.

[0194] It should be noted that the function of S511 is to ensure the safe parking of vehicles.

[0195] S512. Safety warnings are given to people in the driver's cab and outside the vehicle via instruments and buzzers.

[0196] In the above detailed description, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features of the single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, wherein each claim stands alone as a preferred embodiment of the invention.

[0197] The disclosed embodiments have been described above to enable any person skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the spirit and scope of this disclosure. Therefore, this disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0198] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

[0199] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-voltage safety control method for electric vehicles, characterized in that: A high-voltage safety control system for an electric vehicle is utilized; the high-voltage safety control system for the electric vehicle includes a battery box, a collision displacement sensor, battery branches, battery modules, excitation fuses, a distribution box, a main positive contactor (KM1), a main negative contactor (KM2), an emergency disconnect switch (SW1), a BMS controller, a CPDU central power distribution control, a high-voltage load, and instruments; wherein: The collision displacement sensor is used to monitor the collision status of the battery box; the collision displacement sensor is mounted on the battery frame arranged around the battery box; the collision displacement sensor is connected to the CPDU central power distribution control. The battery branch includes the battery module and the excitation fuse; the battery module connects to the high-voltage contact of the excitation fuse to enable the circuit of the battery branch; the control terminal of the excitation fuse is connected to the BMS controller. One of the two control terminals of the main positive contactor (KM1) is connected to the CPDU central power distribution control, and the other terminal is connected to the emergency disconnect switch (SW1). The control terminal of the main negative contactor (KM2) is connected to the central power distribution control of the CPDU; The battery branch includes a first battery branch and a second battery branch; the excitation fuse includes a first excitation fuse (FU1) and a second excitation fuse (FU2); wherein: The battery module in the first battery branch is connected to the high-voltage contact of the first excitation fuse (FU1) to connect the circuit of the first battery branch; the control terminal of the first excitation fuse (FU1) is connected to the BMS controller. The battery module in the second battery branch is connected to the high-voltage contact of the second excitation fuse (FU2) to connect the circuit of the second battery branch; the control terminal of the second excitation fuse (FU2) is connected to the BMS controller. The collision displacement sensor includes a first collision displacement sensor (crash1) and a second collision displacement sensor (crash2). The emergency cut-off switch (SW1) is a dual-contact redundant switch and is equipped with a lock-up mechanism to prevent accidental triggering. The high-voltage safety control method for electric vehicles includes the following steps: S100. Assess the collision hazard level; S200. Assess the severity of battery pack damage; S300. Executes the high-voltage positive and negative output cut-off control process; S400. Execute the internal disconnection control procedure of the battery box; Specifically, S100 includes the following steps: S110. The CPDU central power distribution control collects the deformation displacement from the collision displacement sensor; S120. Based on the deformation displacement, obtain the collision deformation displacement level; S130. Obtain the impact degree of the collision position; S140. Substitute the collision deformation displacement level and the collision position influence degree into the collision hazard level table; then look up the table to obtain the collision hazard degree; The collision hazard level table is an orthogonal matrix formed by the collision deformation displacement level and the collision position influence degree; The collision deformation displacement levels are arranged in ascending order of severity and are divided into L0, L1, L2, and L3 levels; where L0 indicates no impact. The impact of the collision location is arranged in ascending order of severity, and is divided into P1, P2, and P3 levels; where P1 level indicates that the collision location is far from the cockpit; P2 level indicates that the collision location is at a medium distance; and P3 level indicates that the collision location is close to the cockpit. The collision hazard levels are arranged in ascending order of severity and are divided into S0, S1, S2, and S3 levels.

2. The high-voltage safety control method for electric vehicles according to claim 1, characterized in that: SS120 specifically includes the following steps: S121. The deformation displacement is used to calculate the deformation correction amount; the deformation correction amount is expressed by the following formula: in: This is the deformation correction amount; The safety correction factor is preset manually based on the road conditions in which the vehicle is operating; The amount of deformation displacement at the location of the collision displacement sensor, which generates the deformation due to the impact; The deformation displacement of the collision displacement sensor at the initial position; S122. The deformation correction amount is compared with the manually preset collision deformation displacement level threshold range to obtain the corresponding collision deformation displacement level.

3. The high-voltage safety control method for electric vehicles according to claim 2, characterized in that: S130 specifically includes the following steps: S131. The position of the battery pack near the edge of the cockpit is obtained; S132. The position of the driver's seat is obtained; S133. Measure the straight-line distance between the position of the battery pack near the edge of the cockpit and the position of the driver's seat; S134. The straight-line distance between the position of the battery pack near the edge of the cockpit and the position of the driver's seat obtained in S133 is compared with the manually preset collision position influence threshold range to obtain the corresponding collision position influence.

4. The high-voltage safety control method for electric vehicles according to claim 3, characterized in that: S200 specifically includes the following steps: S210. Obtain the collision hazard level obtained in S100; S220. Obtain battery temperature and insulation fault status; S230. Based on the collision hazard level, the battery temperature, and the insulation fault condition, the initial severity of the battery pack collision is determined. S240. By collecting information on insulation failure status and battery pack cell temperature rise through the battery's BMS controller, the confidence level of the initial severity assessment of the battery pack collision is corrected to obtain the corrected severity of the battery pack damage. The initial severity of the battery pack collision is arranged in ascending order of severity and is divided into S0, S1, S2 and S3 levels. The severity of the battery pack damage is arranged in ascending order of severity and is divided into M0, M1, M2 and M3 levels; The initial severity of the battery pack collision at the same level is the same as that represented by the collision hazard level.

5. The high-voltage safety control method for electric vehicles according to claim 4, characterized in that: The high-voltage positive and negative output cut-off control process includes M1 high-voltage positive and negative output cut-off control sub-process, M2 high-voltage positive and negative output cut-off control sub-process, and M3 high-voltage positive and negative output cut-off control sub-process. The S300 specifically includes the following steps: S310. Based on the corrected severity of the battery pack damage, perform the following operations: If the severity of the battery pack damage after correction is level M1, then execute the M1 high voltage positive and negative pole output cut-off control sub-process; If the severity of the battery pack damage after correction is M2, then the M2 high voltage positive and negative pole output cut-off control sub-process is executed; If the severity of the battery pack damage after correction is M3, then the M3 high voltage positive and negative pole output cut-off control sub-process is executed; The M1 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps: S310a. The CPDU central power distribution control obtains fault information from the BMS controller; then performs the following operations based on the fault information: If the fault information is empty, the instrument panel will output the string "The vehicle's battery box has been hit, affecting safety. Please have it repaired as soon as possible." The M2 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps: S310b. The CPDU central power distribution control performs a rapid unloading operation on high-voltage loads, specifically including the following steps: S311b. The CPDU central power distribution control sets the target drive torque of the motor to 0 Nm; S312b. The CPDU central power distribution control controls the electric air compressor, electric air conditioner, and DC-DC converter to stop working; S313b. Collects high-voltage circuit current; S314b. Compare the high-voltage circuit current with a manually preset high-voltage circuit current threshold, and then perform the following operations based on the comparison result: If the high-voltage circuit current is not lower than the high-voltage circuit current threshold, then return and execute S313b again; If the high-voltage circuit current is lower than the high-voltage circuit current threshold, then the main negative contactor (KM2) is controlled to disconnect the negative contactor in sequence, and then the main positive contactor (KM1) is controlled to disconnect the positive contactor. S315b. To provide safety warnings to personnel in the driver's cab and outside the vehicle via the aforementioned instruments and buzzer; The M3 high-voltage positive and negative pole output cutoff control sub-process specifically includes the following steps: S310c. The torque of the CPDU central power distribution control for controlling high-power, high-voltage loads is 0. S311c. Sequentially control the main negative contactor (KM2) to disconnect the negative contactor, and then control the main positive contactor (KM1) to disconnect the positive contactor; S312c. Safety warnings are given to personnel in the driver's cab and outside the vehicle via the instruments and buzzer.

6. The high-voltage safety control method for electric vehicles according to claim 5, characterized in that: The S400 specifically includes the following steps: S410. Check the execution result of the M2 high-voltage positive and negative pole output cutoff control sub-process or the M3 high-voltage positive and negative pole output cutoff control sub-process; then, based on the check result, perform the following operations: If the execution result of the M2 high voltage positive and negative pole output cut-off control sub-process or the M3 high voltage positive and negative pole output cut-off control sub-process is normal cut-off, then the current high voltage safety control ends. If the execution result of the M2 high voltage positive and negative pole output cut-off control sub-process or the M3 high voltage positive and negative pole output cut-off control sub-process is not normal cut-off, or the contactor is burned out, then execute S420. S420. The CPDU central power distribution control requests the BMS controller to activate the control signal of the first excitation fuse (FU1) in the first battery branch, thereby blowing the internal fuse of the battery box; The CPDU central power distribution control requests the control signal of the BMS controller to activate the second excitation fuse (FU2) in the second battery branch, thereby blowing the internal fuse of the battery box.

7. The high-voltage safety control method for electric vehicles according to claim 6, characterized in that: It also includes an emergency high-voltage circuit disconnection procedure; the emergency high-voltage circuit disconnection procedure specifically includes the following steps: S500. Control the emergency disconnect switch (SW1) to disconnect the high-voltage control; specifically including the following steps: S501. The main positive contactor (KM1) is directly disconnected from the circuit; S510. Disconnection Status - Safety Status Protection; specifically includes the following steps: S511. When the CPDU central power distribution control detects that the contacts of the emergency disconnect switch (SW1) are open, the emergency diversion is initiated; S512. Safety warnings are given to people in the driver's cab and outside the vehicle through the instruments and buzzer.

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