Electric vehicle low-voltage power supply system, fault isolation method and electric vehicle

Abstract

The invention provides an electric vehicle low-voltage power supply system, a fault isolation method and an electric vehicle, and relates to the field of electric vehicle low-voltage systems, and a power distribution network of the system comprises a safe load power supply branch, a non-safe load power supply branch and a redundant safe load power supply branch. The direct current conversion unit is connected with the non-safe load power supply branch, and the non-safe load power supply branch is electrically connected with one end of the safe load power supply branch through the main low-voltage energy storage power supply unit; and the other end of the safety load power supply branch is connected with the redundant safety load power supply branch through the redundant low-voltage energy storage power supply unit. According to the system, through collaborative design of the main low-voltage energy storage power supply unit, the redundant low-voltage energy storage power supply unit and the multi-branch power distribution network, independent power supply and dual-power-supply redundant backup of a safe load and a non-safe load are achieved, and the safety redundancy and fault handling capacity of low-voltage power supply of the electric vehicle are remarkably improved.

Description

Technical Field

[0001] This application relates to the field of low-voltage systems for electric vehicles, and more specifically, to a low-voltage power supply system for electric vehicles, a fault isolation method, and an electric vehicle. Background Technology

[0002] In the low-voltage power supply systems of advanced autonomous driving vehicles, core loads require high functional safety levels, typically relying on a dual-power redundant power supply architecture. This involves using power isolation switches to isolate faulty branches in the event of a circuit failure, ensuring normal power supply to the remaining circuits. In existing technologies, power isolation requires the separate addition of isolation switches and corresponding monitoring chips, which not only occupies valuable vehicle installation space but also significantly increases system costs, resulting in poor economic efficiency. Furthermore, some multi-power output circuits lack effective single-power isolation designs, making fault propagation easy and failing to meet the high safety redundancy requirements of autonomous driving vehicles for low-voltage power supply systems. Summary of the Invention

[0003] The purpose of this application is to provide a low-voltage power supply system for electric vehicles, a fault isolation method, and an electric vehicle, so as to solve the above-mentioned problems existing in the prior art and ensure the safety of load power supply.

[0004] In a first aspect, a low-voltage power supply system for electric vehicles is provided, the system comprising: Main low-voltage energy storage power supply unit, redundant low-voltage energy storage power supply unit, DC-DC conversion unit and power distribution network; The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch; The DC-DC conversion unit is connected to the non-safe load power supply branch, and the non-safe load power supply branch is electrically connected to one end of the safe load power supply branch through the main low-voltage energy storage power supply unit; the other end of the safe load power supply branch is connected to the redundant safe load power supply branch through the redundant low-voltage energy storage power supply unit.

[0005] In one possible implementation, the non-safety load power supply branch includes a first electrical box and at least one second electrical box; The DC-DC conversion unit is connected to the input terminal of the first electrical box, and the first output terminal of the first electrical box is connected to the main low-voltage energy storage power unit. For any second electrical box, the second output terminal of the first electrical box is connected to the input terminal of the second electrical box; the output terminal of the second electrical box is connected to a non-safety load.

[0006] In one possible implementation, the main low-voltage energy storage power unit includes: a first positive terminal, a second positive terminal, a negative terminal, a main battery, a main battery main switch, and a main battery isolation switch; The output terminal of the non-safety load power supply branch is connected to the first terminal of the main battery isolation switch through the first positive terminal; the second terminal of the main battery isolation switch is connected to the first terminal of the main battery main switch, the second terminal of the main battery main switch is connected to the positive terminal of the main battery, and the negative terminal of the main battery is connected to the negative terminal. The second terminal of the main battery isolation switch is also connected to the input terminal of the safety load power supply branch through the second positive terminal.

[0007] In one possible implementation, the redundant low-voltage energy storage power unit includes: a first redundant positive terminal, a second redundant positive terminal, a redundant negative terminal, a redundant battery, a redundant battery main switch, and a redundant battery isolation switch. The output terminal of the safe load power supply branch is connected to the first terminal of the redundant battery isolation switch through the first redundant positive terminal; the second terminal of the redundant battery isolation switch is connected to the first terminal of the redundant battery main switch, the second terminal of the redundant battery main switch is connected to the positive terminal of the redundant battery, and the negative terminal of the redundant battery is connected to the redundant negative terminal. The second terminal of the redundant battery isolation switch is also connected to the input terminal of the redundant safety load power supply branch through the second redundant positive terminal.

[0008] In one possible implementation, the main battery main switch, the main battery isolation switch, the redundant battery main switch, and the redundant battery isolation switch are all metal-oxide-semiconductor field-effect transistors.

[0009] Secondly, a fault isolation method for a low-voltage power supply system of an electric vehicle is provided, applied to the aforementioned low-voltage power supply system of an electric vehicle. The low-voltage power supply system of the electric vehicle includes a main low-voltage energy storage power unit, a redundant low-voltage energy storage power unit, a DC-DC conversion unit, and a power distribution network; the power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch; both the main low-voltage energy storage power unit and the redundant low-voltage energy storage power unit are equipped with corresponding switching modules; the method may include: When a fault is detected in at least one of the non-safe load power supply branch, the safe load power supply branch, the redundant safe load power supply branch, the main low-voltage energy storage power unit, and the redundant low-voltage energy storage power unit, a corresponding control command is generated according to the location of the fault. According to the control command, the switching module is controlled to electrically isolate the faulty branch from the normal branch, and to maintain power supply to the safe load and / or redundant safe load that are not affected by the fault.

[0010] In one possible implementation, the switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the power supply branch of the unsafe load, the control of the switching module to turn on or off according to the control command includes: The main battery isolation switch is controlled to open, and the redundant battery isolation switch is controlled to open, so as to supply power to the safe load of the safe load power supply branch. The main battery main switch and the redundant battery main switch are controlled to close, so as to supply power to the redundant safe load of the redundant safe load power supply branch.

[0011] In one possible implementation, the switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the power supply branch of the safety load, the control of the switching module to open or close according to the control command includes: The main battery isolation switch and the main battery main switch are both disconnected, and the redundant battery isolation switch is disconnected. The redundant battery main switch is closed so that the non-safe load of the non-safe load power supply branch is powered through the DC-DC conversion unit, and the redundant safe load of the redundant safe load power supply branch is powered through the redundant low-voltage energy storage power supply unit's redundant battery.

[0012] The switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the redundant safety load power supply branch, the control of the switching module to turn on or off according to the control command includes: The redundant battery isolation switch and the redundant battery main switch are both disconnected, and the main battery isolation switch and the main battery main switch are closed; so as to supply power to the non-safe load and charge the main battery of the main low-voltage energy storage power unit through the DC-DC conversion unit, and supply power to the safe load of the safe load power supply branch through the main battery.

[0013] Thirdly, an electric vehicle is provided, comprising a low-voltage power supply system for an electric vehicle as described in any one of the first aspects.

[0014] Fourthly, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a processor, the computer program implements the steps of any of the methods described in the second aspect above.

[0015] This application provides a low-voltage power supply system for electric vehicles, a fault isolation method, and an electric vehicle. The system includes: a main low-voltage energy storage power unit, a redundant low-voltage energy storage power unit, a DC-DC converter, and a power distribution network. The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch. The DC-DC converter is connected to the non-safe load power supply branch, and the non-safe load power supply branch is electrically connected to one end of the safe load power supply branch through the main low-voltage energy storage power unit. The other end of the safe load power supply branch is connected to the redundant safe load power supply branch through the redundant low-voltage energy storage power unit. Through the coordinated design of the main low-voltage energy storage power unit, the redundant low-voltage energy storage power unit, and the multi-branch power distribution network, this system achieves independent power supply for safe and non-safe loads and dual-power redundant backup, significantly improving the safety redundancy and fault handling capability of the low-voltage power supply for electric vehicles. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a low-voltage power supply system for an electric vehicle provided in an embodiment of this application; Figure 2 A flowchart illustrating a fault isolation method for a low-voltage power supply system of an electric vehicle provided in this application embodiment; Reference numerals: 1-Main low-voltage energy storage power unit, 2-Main battery isolation switch, 3-Main battery main switch, 4-First positive terminal, 5-Second positive terminal, 6-Negative terminal, 7-Redundant low-voltage energy storage power unit, 8-Redundant battery main switch, 9-Redundant battery isolation switch, 10-First redundant positive terminal, 11-Second redundant positive terminal, 12-Redundant negative terminal, 13-Main circuit, 14-Redundant circuit, 15-DC conversion unit, 16-First electrical box, 17-Second electrical box, 18-Third electrical box, 19-Fourth electrical box, 20-First group of non-safety loads, 21-Second group of non-safety loads, 22-Safety loads, 23-Redundant safe loads. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0019] In the low-voltage power supply systems of advanced autonomous driving vehicles, core loads require high functional safety levels, typically relying on a dual-power redundant power supply architecture. This involves using power isolation switches to isolate faulty branches in the event of a circuit failure, ensuring normal power supply to the remaining circuits. In existing technologies, power isolation requires the separate addition of isolation switches and corresponding monitoring chips, which not only occupies valuable vehicle installation space but also significantly increases system costs, resulting in poor economic efficiency. Furthermore, some multi-power output circuits lack effective single-power isolation designs, making fault propagation easy and failing to meet the high safety redundancy requirements of autonomous driving vehicles for low-voltage power supply systems.

[0020] Therefore, this application provides a low-voltage power supply system for electric vehicles, a fault isolation method, and an electric vehicle, which solves the above-mentioned problems existing in the prior art and can ensure the safety of load power supply.

[0021] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application. Furthermore, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0022] Figure 1 This is a schematic diagram of a low-voltage power supply system for an electric vehicle provided in an embodiment of this application, as shown below. Figure 1 As shown, the low-voltage power supply system for electric vehicles includes: a main low-voltage energy storage power supply unit 1, a redundant low-voltage energy storage power supply unit 7, a DC-DC conversion unit 15, and a power distribution network. A. The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch; each branch corresponds to the power supply of loads with different safety levels in the vehicle: the safe load power supply branch is used to connect the safe load 22 (such as the steering and braking control system), the non-safe load power supply branch is used to connect the non-safe load (such as the first group of non-safe loads 20 and the second group of non-safe loads 21, including in-vehicle entertainment and window control), and the redundant safe load power supply branch is used to connect the redundant safe load 23 (the spare parts of the safe load 22).

[0023] The DC-DC conversion unit 15 is connected to the non-safety load power supply branch, and the non-safety load power supply branch is electrically connected to one end of the safe load power supply branch through the main low-voltage energy storage power supply unit 1; the other end of the safe load power supply branch is connected to the redundant safe load power supply branch through the redundant low-voltage energy storage power supply unit 7. This method forms a complete power supply link for conversion, energy storage and power distribution.

[0024] The core function of the DC-DC conversion unit 15 is to convert the high-voltage electricity (200V-450V) from the high-voltage bus of the electric vehicle into low-voltage DC electricity of 13.5V-14.5V, and its output terminal is connected to the power supply branch of the non-safe load.

[0025] Furthermore, the non-safety load power supply branch includes a first electrical box 16 and at least one second electrical box 17 (in this embodiment, one second electrical box 17 is provided to accommodate two sets of non-safety loads; if the number of non-safety loads in the vehicle increases, the number of second electrical boxes 17 can be increased). The specific connection relationship is as follows: the DC-DC converter unit 15 (main DC-DC) is connected to the input terminal of the first electrical box 16, and the first output terminal of the first electrical box 16 is connected to the main low-voltage energy storage power unit 1. For any second electrical box 17, the second output terminal of the first electrical box 16 is connected to the input terminal of the second electrical box 17; the output terminal of the second electrical box 17 is connected to a non-safety load.

[0026] It is understood that the first electrical box 16 has multiple second output terminals for connecting to each of the second electrical boxes 17 respectively. In this embodiment, the multiple second output terminal design of the first electrical box 16 can flexibly adapt to the quantity requirements of non-safety loads in different vehicle models. By simply increasing the number of second electrical boxes 17 and correspondingly connecting them to the second output terminals of the first electrical box 16, the power supply channels for non-safety loads can be expanded, demonstrating good versatility.

[0027] B. The main low-voltage energy storage power unit 1 includes: a first positive terminal 4, a second positive terminal 5, a negative terminal 6, a main battery, a main battery main switch 3, and a main battery isolation switch 2. The main battery, serving as the core of the main low-voltage energy storage power unit 1, employs a series / parallel design of lithium-ion battery cells with a rated voltage of 12V. The main battery isolation switch 2 utilizes a metal-oxide-semiconductor field-effect transistor (MOSFET), whose core functions are fault isolation and power distribution. It can achieve electrical isolation between the power supply branches for unsafe loads and those for safe loads based on the circuit status, preventing unsafe load faults (such as short circuits) from affecting the power supply to safe loads. The main battery main switch 3 also uses a MOSFET device and is connected in series between the main battery and the main battery isolation switch 2. The core function is to control the charging and discharging of the main battery. When the main battery itself malfunctions (such as overvoltage or overcurrent) or the safety load branch malfunctions, it can disconnect the main battery from the external circuit to protect the main battery body. The first positive terminal 4, the second positive terminal 5, and the negative terminal 6 are all made of copper conductive pillars with nickel plating to improve conductivity and corrosion resistance. Among them, the first positive terminal 4 is a dedicated input terminal for charging, the second positive terminal 5 is a dedicated output terminal for power supply to the safety load, and the negative terminal 6 is a common ground terminal. The three are connected to the external circuit through independent terminals to avoid mutual interference between current paths of different functions.

[0028] The output terminal of the non-safety load power supply branch (i.e. the first output terminal of the first electrical box 16) is connected to the first terminal of the main battery isolation switch through the first positive terminal 4; the second terminal of the main battery isolation switch 2 is connected to the first terminal of the main battery main switch 3, the second terminal of the main battery main switch 3 is connected to the positive terminal of the main battery, and the negative terminal of the main battery is connected to the negative terminal 6. The second terminal of the main battery isolation switch 2 is also connected to the input terminal of the safety load power supply branch through the second positive terminal 5.

[0029] In other words, the other end of the first positive terminal 4 is electrically connected to the first terminal (source) of the main battery isolation switch 2, and the second terminal (drain) of the main battery isolation switch 2 forms two branches: The first branch is electrically connected to the first terminal (source) of the main battery main switch 3. The second terminal (drain) of the main battery main switch 3 is electrically connected to the positive terminal tab of the main battery through a wire. The negative terminal tab of the main battery is electrically connected to the negative terminal 6. The negative terminal 6 is finally connected to the low-voltage grounding circuit of the whole vehicle, forming a closed-loop charging circuit for the main battery. The second branch is electrically connected to one end of the second positive terminal 5 via a wire, and the other end of the second positive terminal 5 is electrically connected to the input terminal of the safety load power supply branch (the input terminal of the third electrical box 18), forming a closed loop circuit for the main battery to supply power to the safety load.

[0030] In summary, when the DC-DC conversion unit 15 is working normally, its output low-voltage electricity is distributed by the first electrical box 16 and input to the main low-voltage energy storage power unit 1 through the first positive terminal 4. At this time, the main battery isolation switch 2 and the main battery main switch 3 are both in the closed state, and electrical energy is injected into the main battery in sequence through the main battery isolation switch 2 and the main battery main switch 3 to complete the charging. At the same time, electrical energy is output to the safety load power supply branch through the second positive terminal through the main battery isolation switch to ensure the continuous operation of the safety load 22. When the first group of non-safe loads 20 is short-circuited, the control module triggers the main battery isolation switch 2 to open, cutting off the path from the first positive terminal 4 to the main battery isolation switch 2; at the same time, the main battery main switch remains closed, and the main battery can still supply power to the safe load through the second positive terminal, ensuring that the safe load is not affected by the fault. When the safety load 22 is short-circuited, the main battery isolation switch 2 and the main battery main switch 3 are triggered to disconnect, which not only cuts off the connection between the main battery and the safety load to prevent the main battery from continuously discharging to the short-circuited safety load, but also cuts off the connection between the non-safety load branch and the safety load branch, achieving double isolation and ensuring the safety of the non-safety load branch and the main battery.

[0031] C. The redundant low-voltage energy storage power unit 7 includes: a first redundant positive terminal 10, a second redundant positive terminal 11, a redundant negative terminal 12, a redundant battery, a redundant battery main switch 8, and a redundant battery isolation switch 9. The redundant battery uses a series / parallel design of lithium-ion cells with a rated voltage of 12V. It forms a dual energy storage backup with the main battery, preventing power loss to the safe load due to the failure of a single energy storage unit. The redundant battery isolating switch 9 uses the same type of metal-oxide-semiconductor field-effect transistor (MOSFET) as the main battery isolating switch 2. Its core functions are main circuit isolation and redundant power supply switching: under normal conditions, it connects the safe load power supply branch to the charging path of the redundant battery; in case of a fault (such as a short circuit in the main circuit 13 or an abnormality in the redundant battery), it disconnects the path, isolating the redundant unit from the fault source. The redundant battery main switch 8 also uses a MOSFET device, connected in series between the redundant battery and the redundant battery isolating switch 9. Its core function is to control the charging and discharging of the redundant battery. When the redundant battery experiences overvoltage, overcurrent, or overtemperature faults, it can quickly disconnect the redundant battery from the external circuit, protecting the battery itself and other system components. The first redundant positive terminal is a dedicated input terminal for charging redundant batteries (receiving power from the main circuit), the second redundant positive terminal is a dedicated output terminal for powering redundant safety loads, and the redundant negative terminal is a common ground terminal. All three are connected to the external circuit through independent terminals to avoid current interference in the charging and power supply paths.

[0032] The output terminal of the safety load power supply branch is connected to the first terminal of the redundant battery isolation switch 9 through the first redundant positive terminal 10; the second terminal of the redundant battery isolation switch 9 is connected to the first terminal of the redundant battery main switch 8, the second terminal of the redundant battery main switch 8 is connected to the positive terminal of the redundant battery, and the negative terminal of the redundant battery is connected to the redundant negative terminal 12. The second terminal of the redundant battery isolation switch 9 is also connected to the input terminal of the redundant safety load power supply branch through the second redundant positive terminal 11.

[0033] In other words, the output end of the safety load power supply branch (i.e., the output end of the third electrical box 18) is electrically connected to the terminal of the first redundant positive terminal (first redundant positive terminal 10) through a wire; the other end of the first redundant positive terminal is electrically connected to the first terminal (source) of the redundant battery isolation switch 9; the second terminal (drain) of the redundant battery isolation switch 9 is electrically connected to the first terminal (source) of the redundant battery main switch 8; the second terminal (drain) of the redundant battery main switch 8 is electrically connected to the positive terminal tab of the redundant battery; the negative terminal tab of the redundant battery is electrically connected to the redundant negative terminal 12, and the redundant negative terminal 12 is electrically connected to the low-voltage grounding terminal of the vehicle, forming a closed-loop charging circuit for the redundant battery.

[0034] The second terminal (drain) of the redundant battery isolating switch 9 is also electrically connected to one end of the second redundant positive terminal 11 via a wire; the other end of the second redundant positive terminal is electrically connected to the input terminal of the redundant safety load power supply branch (i.e., the input terminal of the fourth electrical box 19); the output terminal of the fourth electrical box 19 is electrically connected to the redundant safety load 23 (such as a backup steering control module or a backup brake monitoring module), forming a closed-loop circuit for the redundant battery to supply power to the redundant safety load.

[0035] Combination Figure 1 As shown, the main circuit 13 is the main power supply link, and its core components include a DC-DC conversion unit 15, a first electrical box 16, a second electrical box 17, a main low-voltage energy storage power supply unit 1, and a third electrical box 18. Its function is to cover the daily power supply for non-safe loads and safe loads, and at the same time charge the main battery. It is the core energy transmission circuit of the vehicle's low-voltage system.

[0036] Redundant circuit 14 is a backup power supply link, and its core components include redundant low-voltage energy storage power unit 7 and fourth electrical box 19. Its function is to take over the power supply to the backup components (redundant safety load 23) of the main circuit safety load when the main circuit fails, forming a dual redundancy architecture with the main circuit to ensure the continuity and safety of power supply.

[0037] In summary, when both the main low-voltage energy storage power supply unit 1 and the safety load power supply branch are normal, the redundant battery isolation switch 9 and the redundant battery main switch 8 are closed. The electrical energy output by the DC-DC conversion unit 15 is used to charge the redundant battery through the first electrical box 16, the main low-voltage energy storage power supply unit 1, the third electrical box 18, and the first redundant positive terminal 10, via the redundant battery isolation switch 9 and the redundant battery main switch 8. At this time, the redundant safety load 23 is indirectly powered by the main circuit, and the redundant battery is in a fully charged standby state, ready for emergency response.

[0038] If the main battery experiences overvoltage or overcurrent, or if the main battery isolation switch 2 fails, and the main circuit cannot supply power to the safety load 22, the redundant battery isolation switch 9 is triggered to remain closed, and the redundant battery main switch 8 remains closed. The redundant battery supplies power to the redundant safety load 23 through the redundant battery main switch 8, the second redundant positive terminal 11, and the fourth electrical box 19. At the same time, the DC-DC conversion unit 15 continues to charge the redundant battery through the third electrical box 18, ensuring the continuous operation of the redundant safety load 23.

[0039] If the redundant battery experiences overvoltage, it triggers the closing of the redundant battery isolation switch 9 and the opening of the redundant battery main switch 8, cutting off the connection between the redundant battery and the main circuit and the redundant safety load 23, thus preventing the overvoltage fault from spreading to the main circuit. At this time, the redundant safety load 23 is indirectly powered by the main DC-DC converter unit 15 through the main circuit, ensuring that the core safety function is not interrupted.

[0040] In some embodiments, the main battery main switch, the main battery isolation switch, the redundant battery main switch, and the redundant battery isolation switch all include a discharge MOS and a charging MOS. Each discharge MOS is dedicated to controlling the on / off state of the power supply path from the corresponding battery to the load (such as a safety load or a redundant safety load), while each charging MOS is dedicated to controlling the on / off state of the charging path from external power (such as the output of a DC-DC converter) to the corresponding battery. Both can execute on / off commands independently.

[0041] This application achieves three core technical effects through a dual-power redundancy architecture and integrated switch design: First, the safety redundancy is significantly improved. The main low-voltage energy storage power unit and the redundant low-voltage energy storage power unit form a dual backup. Combined with integrated switches such as the main battery isolation switch and the redundant battery isolation switch (including independent charging and discharging MOS), typical faults (such as battery overvoltage, circuit short circuit, switch sticking, etc.) can be accurately isolated. This ensures that after the faulty branch is disconnected, the remaining circuits (such as safe loads and non-safe loads) can still be powered normally, fully meeting the safety requirements of high-level intelligent assisted driving vehicles for zero interruption of low-voltage systems.

[0042] Secondly, it has significant advantages in terms of space and cost. The main switch and disconnector of the main / redundant battery are integrated into the energy storage unit, replacing the disconnector and monitoring components that are set separately in the traditional solution. This saves vehicle installation space, reduces hardware costs, and combines compactness and economy.

[0043] Third, it has strong functional scalability and compatibility. The multi-electrical box design of the non-safety load power supply branch can flexibly adapt to the load quantity requirements of different vehicle models. The symmetrical redundancy architecture of the dual power supply can also be compatible with the future expansion of intelligent driving functions (such as adding safety loads). While ensuring existing functions, it reserves sufficient redundancy for system upgrades.

[0044] This application provides a low-voltage power supply system for electric vehicles. The system includes: a main low-voltage energy storage power unit, a redundant low-voltage energy storage power unit, a DC-DC converter, and a power distribution network. The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch. The DC-DC converter is connected to the non-safe load power supply branch, and the non-safe load power supply branch is electrically connected to one end of the safe load power supply branch through the main low-voltage energy storage power unit. The other end of the safe load power supply branch is connected to the redundant safe load power supply branch through the redundant low-voltage energy storage power unit. Through the coordinated design of the main low-voltage energy storage power unit, the redundant low-voltage energy storage power unit, and the multi-branch power distribution network, this system achieves independent power supply for safe and non-safe loads and dual-power redundant backup, significantly improving the safety redundancy and fault handling capability of the low-voltage power supply for electric vehicles.

[0045] This application also provides an electric vehicle, specifically an electric vehicle with advanced intelligent assisted driving functions, which includes the aforementioned low-voltage power supply system for electric vehicles. This system is integrated into the overall low-voltage power distribution architecture of the electric vehicle. A DC-DC converter is connected to the vehicle's high-voltage bus to obtain high-voltage power. Each branch of the power distribution network is electrically connected to the vehicle's safety loads (such as steering control modules and brake monitoring modules), non-safety loads (such as in-vehicle entertainment systems and window controllers), and redundant safety loads. Through a dual-redundancy design of the main low-voltage energy storage power unit and redundant low-voltage energy storage power units, combined with an integrated switching architecture with independent control of charging and discharging MOS, the system ensures the continuity of power supply and fault isolation for the core loads of intelligent driving, significantly improving the power supply safety level and functional redundancy capability of the electric vehicle under complex operating conditions, and meeting the stringent requirements of advanced intelligent assisted driving for zero-interruption and high reliability of the low-voltage power supply system.

[0046] Figure 2 This is a flowchart illustrating a fault isolation method for a low-voltage power supply system of an electric vehicle, provided as an embodiment of this application. Figure 2As shown, the electric vehicle low-voltage power supply system described above includes a main low-voltage energy storage power unit, a redundant low-voltage energy storage power unit, a DC-DC conversion unit, and a power distribution network. The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch. Both the main low-voltage energy storage power unit and the redundant low-voltage energy storage power unit are equipped with corresponding switching modules. The method includes: Step S210: When at least one of the following is detected to be faulty: non-safe load power supply branch, safe load power supply branch, redundant safe load power supply branch, main low-voltage energy storage power unit and redundant low-voltage energy storage power unit, generate corresponding control commands according to the location of the fault. Step S220: According to the control command, control the switching module to electrically isolate the faulty branch from the normal branch, and maintain power supply to the safe load and / or redundant safe load that are not affected by the fault.

[0047] Furthermore, the switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. A. When a fault is detected in the power supply branch of a non-safe load, the control switch module is switched on and off according to the control command, including: The main battery isolation switch is opened, and the redundant battery isolation switch is opened to supply power to the safe load of the safe load power supply branch. The main battery main switch and the redundant battery main switch are closed to supply power to the redundant safe load of the redundant safe load power supply branch.

[0048] B. When a fault is detected in the power supply branch of the safe load, the control switch module is switched on and off according to the control command, including: The main battery isolation switch and the main battery main switch are both opened, and the redundant battery isolation switch is opened and the redundant battery main switch is closed, so as to supply power to the non-safe load power supply branch through the DC-DC conversion unit, and to supply power to the redundant safe load power supply branch through the redundant low-voltage energy storage power supply unit's redundant battery.

[0049] C. When a fault is detected in the redundant safety load power supply branch, the control switch module is switched on and off according to the control command, including: The redundant battery isolation switch and the redundant battery main switch are both opened, and the main battery isolation switch and the main battery main switch are closed; so as to supply power to the non-safe load through the DC-DC conversion unit and charge the main battery of the main low-voltage energy storage power unit, and supply power to the safe load of the safe load power supply branch through the main battery.

[0050] The aforementioned fault locations A, B, and C (such as non-safety load short circuit, safe load short circuit, and redundant safe load short circuit) are merely illustrative examples of the fault isolation method in this application and are not intended to limit the fault scenarios. In some embodiments, in conjunction with Tables 1 and 2, the fault isolation method of this application can also cover various fault conditions recorded in Table 1. Table 1 summarizes 25 typical fault scenarios, covering battery faults (such as redundant battery overvoltage, main battery undervoltage, and redundant battery overtemperature), circuit faults, and switch circuit faults. Under all the aforementioned fault scenarios, the fault branch isolation and the normal power supply of the remaining circuit can be achieved by controlling the on / off state of the charging and discharging MOS of the main battery main switch, main battery isolation switch, redundant battery main switch, and redundant battery isolation switch, thereby ensuring the safety redundancy of the vehicle's low-voltage system.

[0051] Table 1

[0052] Table 2

[0053] In another embodiment provided in this application, a computer-readable storage medium is also provided, which stores instructions that, when executed on a computer, cause the computer to perform a fault isolation method for a low-voltage power supply system of an electric vehicle as described in any of the above embodiments.

[0054] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute a fault isolation method for a low-voltage power supply system of an electric vehicle as described in any of the above embodiments.

[0055] Those skilled in the art will understand that the embodiments in this application can be provided as methods, systems, or computer program products. Therefore, the embodiments in this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the embodiments in this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0056] This application describes embodiments of methods, apparatus (systems), and computer program products according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0057] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0058] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0059] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected," "coupled," or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0060] Although preferred embodiments have been described in this application, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the embodiments in this application are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments in this application.

[0061] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the embodiments of this application and their equivalents, then these modifications and variations are also intended to be included in the embodiments of this application.

Claims

1. A low-voltage power supply system for electric vehicles, characterized in that, The system includes: a main low-voltage energy storage power supply unit, a redundant low-voltage energy storage power supply unit, a DC-DC conversion unit, and a power distribution network; The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch; The DC-DC conversion unit is connected to the non-safe load power supply branch, and the non-safe load power supply branch is electrically connected to one end of the safe load power supply branch through the main low-voltage energy storage power supply unit; the other end of the safe load power supply branch is connected to the redundant safe load power supply branch through the redundant low-voltage energy storage power supply unit.

2. The system as described in claim 1, characterized in that, The non-safety load power supply branch includes a first electrical box and at least one second electrical box; The DC-DC conversion unit is connected to the input terminal of the first electrical box, and the first output terminal of the first electrical box is connected to the main low-voltage energy storage power unit. For any second electrical box, the second output terminal of the first electrical box is connected to the input terminal of the second electrical box; the output terminal of the second electrical box is connected to a non-safety load.

3. The system as described in claim 1, characterized in that, The main low-voltage energy storage power unit includes: a first positive terminal, a second positive terminal, a negative terminal, a main battery, a main battery main switch, and a main battery isolation switch; The output terminal of the non-safety load power supply branch is connected to the first terminal of the main battery isolation switch through the first positive terminal; the second terminal of the main battery isolation switch is connected to the first terminal of the main battery main switch, the second terminal of the main battery main switch is connected to the positive terminal of the main battery, and the negative terminal of the main battery is connected to the negative terminal. The second terminal of the main battery isolation switch is also connected to the input terminal of the safety load power supply branch through the second positive terminal.

4. The system as described in claim 3, characterized in that, The redundant low-voltage energy storage power unit includes: a first redundant positive terminal, a second redundant positive terminal, a redundant negative terminal, a redundant battery, a redundant battery main switch, and a redundant battery isolation switch; The output terminal of the safe load power supply branch is connected to the first terminal of the redundant battery isolation switch through the first redundant positive terminal; the second terminal of the redundant battery isolation switch is connected to the first terminal of the redundant battery main switch, the second terminal of the redundant battery main switch is connected to the positive terminal of the redundant battery, and the negative terminal of the redundant battery is connected to the redundant negative terminal. The second terminal of the redundant battery isolation switch is also connected to the input terminal of the redundant safety load power supply branch through the second redundant positive terminal.

5. The system as described in claim 3 or 4, characterized in that, The main battery main switch, the main battery isolation switch, the redundant battery main switch, and the redundant battery isolation switch are all metal-oxide-semiconductor field-effect transistors.

6. A fault isolation method for a low-voltage power supply system of an electric vehicle, characterized in that, The method is applied to the low-voltage power supply system for electric vehicles according to any one of claims 1-5. The low-voltage power supply system for electric vehicles includes a main low-voltage energy storage power unit, a redundant low-voltage energy storage power unit, a DC-DC conversion unit, and a power distribution network. The power distribution network includes: a safe load power supply branch, a non-safe load power supply branch, and a redundant safe load power supply branch. Both the main low-voltage energy storage power unit and the redundant low-voltage energy storage power unit are equipped with corresponding switching modules. When a fault is detected in at least one of the non-safe load power supply branch, the safe load power supply branch, the redundant safe load power supply branch, the main low-voltage energy storage power unit, and the redundant low-voltage energy storage power unit, a corresponding control command is generated according to the location of the fault. According to the control command, the switching module is controlled to electrically isolate the faulty branch from the normal branch, and to maintain power supply to the safe load and / or redundant safe load that are not affected by the fault.

7. The method as described in claim 6, characterized in that, The switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the power supply branch of the unsafe load, the control of the switching module to turn on or off according to the control command includes: The main battery isolation switch is controlled to open, and the redundant battery isolation switch is controlled to open, so as to supply power to the safe load of the safe load power supply branch. The main battery main switch and the redundant battery main switch are controlled to close, so as to supply power to the redundant safe load of the redundant safe load power supply branch.

8. The method as described in claim 6, characterized in that, The switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the power supply branch of the safety load, the control of the switching module to open or close according to the control command includes: The main battery isolation switch and the main battery main switch are both disconnected, and the redundant battery isolation switch is disconnected. The redundant battery main switch is closed so that the non-safe load of the non-safe load power supply branch is powered through the DC-DC conversion unit, and the redundant safe load of the redundant safe load power supply branch is powered through the redundant low-voltage energy storage power supply unit's redundant battery.

9. The method as described in claim 6, characterized in that, The switching module of the main low-voltage energy storage power unit includes: a main battery main switch and a main battery isolation switch; the switching module of the redundant low-voltage energy storage power unit includes: a redundant battery main switch and a redundant battery isolation switch. When a fault is detected in the redundant safety load power supply branch, the control of the switching module to turn on or off according to the control command includes: The redundant battery isolation switch and the redundant battery main switch are both disconnected, and the main battery isolation switch and the main battery main switch are closed; so as to supply power to the non-safe load and charge the main battery of the main low-voltage energy storage power unit through the DC-DC conversion unit, and supply power to the safe load of the safe load power supply branch through the main battery.

10. An electric vehicle, characterized in that, It includes a low-voltage power supply system for electric vehicles as described in any one of claims 1 to 5.

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