Vehicle control method and controller

Abstract

The embodiment of the application provides a vehicle control method and a controller, the method is applied to a motor controller, the motor controller is arranged in a vehicle, the vehicle further comprises a vehicle controller, a low-voltage storage battery and a vehicle-mounted charging device, and the method comprises the following steps: receiving a first instruction, the first instruction is sent by the vehicle controller to the motor controller when the vehicle controller determines that the low-voltage storage battery is in a power shortage state, the power shortage state is a state in which the electric quantity of the low-voltage storage battery is less than a preset threshold value; limiting the driving speed of the vehicle according to the first instruction; receiving a second instruction, the second instruction is sent by the vehicle controller to the motor controller after the vehicle controller controls the vehicle-mounted charging device to charge the low-voltage storage battery so that the low-voltage storage battery is separated from the power shortage state; and removing the limitation on the driving speed of the vehicle according to the second instruction. By adopting the embodiment of the application, the safety risk caused by the failure of the vehicle-mounted charging device can be effectively avoided, and the safety of the vehicle during driving is significantly improved.

Description

[0001] This application is a divisional application. The original application has the application number 202010240079.0 and the original application date is March 30, 2020. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of new energy vehicle technology, and in particular to a vehicle control method and controller. Background Technology

[0003] Traditional gasoline-powered vehicles rely on an engine to drive an alternator to generate electricity, which then powers auxiliary electrical equipment. Similarly, pure electric vehicles and hybrid vehicles use direct current converters (DCDC) to convert the high-voltage direct current from the battery pack into low-voltage direct current, thereby powering low-voltage electrical equipment (such as lighting systems, instrument systems, wipers, and various controllers) and charging the low-voltage battery. The low-voltage battery can also power low-voltage electrical equipment.

[0004] When a DC-DC converter malfunctions, such as a short circuit, the excessive short-circuit current can cause the output voltage of the low-voltage battery to decrease. This prevents the low-voltage battery from providing the normal operating voltage for low-voltage electrical equipment, which can easily lead to traffic accidents when vehicles are traveling at high speeds. Therefore, how to effectively avoid the safety risks caused by DC-DC converter malfunctions is a problem that those skilled in the art are researching. Summary of the Invention

[0005] This application discloses a vehicle control method and controller, which can effectively avoid safety risks caused by malfunctions in on-board charging equipment and significantly improve vehicle safety during driving.

[0006] In a first aspect, embodiments of this application provide a vehicle control method applied to a motor controller, the motor controller being located within a vehicle, the vehicle further including a vehicle controller, a low-voltage battery, and an on-board charging device; the method includes: receiving a first instruction, the first instruction being sent by the vehicle controller to the motor controller when it determines that the low-voltage battery is in a depleted state, the depleted state being a state where the charge of the low-voltage battery is less than a preset threshold; limiting the vehicle's driving speed according to the first instruction; receiving a second instruction, the second instruction being sent by the vehicle controller to the motor controller after the vehicle controller controls the on-board charging device to charge the low-voltage battery to remove the low-voltage battery from the depleted state; and releasing the speed limit on the vehicle according to the second instruction.

[0007] In the above method, when the low-voltage battery is in a discharged state, the motor controller limits the vehicle's speed; once the low-voltage battery is out of the discharged state, the motor controller releases the speed limit. Therefore, when the low-voltage battery is discharged, a malfunction in the onboard charging equipment will cause the battery to lose power, but because the vehicle's speed is limited, the safety risk is relatively low. Similarly, when the low-voltage battery is out of the discharged state, a malfunction in the onboard charging equipment will not cause the battery to lose power, and therefore releasing the speed limit will not pose a significant safety risk. This significantly improves vehicle safety during driving and ensures that the vehicle travels at the user-required speed, thus prioritizing user experience.

[0008] In one possible implementation, when the charge of the low-voltage battery is less than the preset threshold, the charge of the low-voltage battery is insufficient to blow the fuse between the on-board charging device and the low-voltage battery.

[0009] In some embodiments, the fuse is used to melt the fusible element when the current exceeds a preset current threshold. That is, when the current of the fuse exceeds the preset current threshold, the bus between the on-board charging device and the low-voltage battery will be disconnected.

[0010] In the above method, when the low-voltage battery is in a depleted state, if the on-board charging equipment malfunctions, although the low-voltage battery cannot be separated from the malfunctioning on-board charging equipment in time, resulting in rapid power loss, the vehicle's safety risk is also relatively small because the vehicle's driving speed is limited, thus significantly improving the vehicle's safety during driving.

[0011] In one possible implementation, limiting the vehicle's speed according to the first instruction includes: controlling the vehicle to decelerate according to the first instruction, or controlling the vehicle to stop moving according to the first instruction.

[0012] Secondly, embodiments of this application provide a motor controller, which is located inside a vehicle. The vehicle also includes a vehicle controller, a low-voltage battery, and an on-board charging device. The motor controller is configured to perform the following operations: receiving a first instruction, which is sent by the vehicle controller to the motor controller when it determines that the low-voltage battery is in a depleted state, wherein the depleted state is defined as the low-voltage battery's charge being less than a preset threshold; limiting the vehicle's speed according to the first instruction; receiving a second instruction, which is sent by the vehicle controller to the motor controller after the vehicle controller controls the on-board charging device to charge the low-voltage battery to remove the low-voltage battery from the depleted state; and releasing the speed limit on the vehicle according to the second instruction.

[0013] In the aforementioned device, when the low-voltage battery is in a depleted state, the motor controller limits the vehicle's speed; once the low-voltage battery is out of the depleted state, the motor controller releases the speed limit. Therefore, when the low-voltage battery is depleted, a malfunction in the onboard charging equipment will cause the battery to lose power, but because the vehicle's speed is limited, the safety risk is relatively low. Similarly, when the low-voltage battery is out of the depleted state, a malfunction in the onboard charging equipment will not cause the battery to lose power, and therefore releasing the speed limit does not pose a significant safety risk. This significantly improves vehicle safety during driving and ensures that the vehicle travels at the user-required speed, thus prioritizing user experience.

[0014] In one possible implementation, when the charge of the low-voltage battery is less than the preset threshold, the charge of the low-voltage battery is insufficient to blow the fuse between the on-board charging device and the low-voltage battery.

[0015] In some embodiments, the fuse is used to melt the fusible element when the current exceeds a preset current threshold. That is, when the current of the fuse exceeds the preset current threshold, the bus between the on-board charging device and the low-voltage battery will be disconnected.

[0016] In the aforementioned device, when the low-voltage battery is in a depleted state, if the on-board charging equipment malfunctions, although the low-voltage battery cannot be separated from the malfunctioning on-board charging equipment in time, resulting in rapid power loss, the vehicle's safety risk is relatively small due to the limited vehicle speed, thus significantly improving the vehicle's safety during driving.

[0017] In one possible implementation, limiting the vehicle's speed according to the first instruction includes: controlling the vehicle to decelerate according to the first instruction, or controlling the vehicle to stop moving according to the first instruction.

[0018] Fourthly, embodiments of this application provide a vehicle, the vehicle including a vehicle controller, a low-voltage battery, an on-board charging device, and a motor controller, wherein the motor controller is the motor controller described in the second aspect, or any implementation thereof.

[0019] Fifthly, embodiments of this application provide a computer-readable storage medium storing instructions that, when executed on a processor, implement the method described in the first aspect or any implementation thereof.

[0020] Sixthly, embodiments of this application provide a chip system, the chip system including at least one processor, a memory and an interface circuit, the memory, the interface circuit and the at least one processor being interconnected via lines, the memory storing a computer program, and when the computer program is executed by the at least one processor, implementing the method described in the first aspect or any implementation thereof.

[0021] It should be understood that the descriptions of technical features, technical solutions, beneficial effects, or similar language in this application do not imply that all features and advantages can be achieved in any single embodiment. Rather, it is understood that the description of a feature or beneficial effect means that a specific technical feature, technical solution, or beneficial effect is included in at least one embodiment. Therefore, the descriptions of technical features, technical solutions, or beneficial effects in this specification do not necessarily refer to the same embodiment. Furthermore, the technical features, technical solutions, and beneficial effects described in this embodiment can be combined in any suitable manner. Those skilled in the art will understand that embodiments can be implemented without one or more specific technical features, technical solutions, or beneficial effects of a particular embodiment. In other embodiments, additional technical features and beneficial effects may be identified in specific embodiments that do not embody all embodiments. Attached Figure Description

[0022] The accompanying drawings used in the embodiments of this application are described below.

[0023] Figure 1A This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application;

[0024] Figure 1B This is a schematic diagram of a low-voltage power supply system provided in an embodiment of this application;

[0025] Figure 1C This is a schematic diagram of another low-voltage power supply system provided in the embodiments of this application;

[0026] Figure 2 This is a schematic flowchart of a vehicle control method provided in an embodiment of this application;

[0027] Figure 3 This is a schematic flowchart of another vehicle control method provided in the embodiments of this application;

[0028] Figure 4 This is a schematic diagram of the structure of a vehicle controller provided in an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of another vehicle controller provided in the embodiments of this application;

[0030] Figure 6This is a schematic diagram of the structure of a motor controller provided in an embodiment of this application. Detailed Implementation

[0031] The embodiments of this application are described below with reference to the accompanying drawings.

[0032] Please see Figure 1A , Figure 1A This is a schematic diagram of a vehicle structure provided in an embodiment of this application. The vehicle can be a pure electric vehicle or a hybrid vehicle. The vehicle may include a low-voltage power supply system 10 and low-voltage electrical equipment 20. The low-voltage power supply system 10 can supply power to the low-voltage electrical equipment 20 through the vehicle bus to enable the low-voltage electrical equipment 20 to operate normally. The vehicle bus may be, but is not limited to, a local interconnect network (LIN) bus, a controller area network (CAN) bus, etc.; the low-voltage electrical equipment 20 may include, but is not limited to, lighting systems, instrument systems, body accessories (such as horns, windshields, windshield wipers, defrosting devices, air conditioning devices, etc.) and various related controllers.

[0033] Please see Figure 1B and Figure 1C , Figure 1B and Figure 1C This is a schematic diagram of the low-voltage power supply system 10 provided in an embodiment of this application. The low-voltage power supply system 10 may include an on-board charging device 11, a low-voltage battery 12, a vehicle control unit (VCU) 13, and a motor control unit (MCU) 14. The on-board charging device 11 is electrically connected to the low-voltage battery 12 via a bus, and the on-board charging device 11 and the VCU 13 are connected via a vehicle bus. In some embodiments, the VCU 13 can control the MCU 14 to adjust the vehicle's driving speed. For example, the VCU 13 can send commands to the MCU 14 to control gear position, accelerator, or brake, etc., and the MCU 14 can drive the vehicle motor according to the above commands to adjust the vehicle's driving speed.

[0034] The on-board charging device 11 can be a device with a direct current (DCDC) converter function. For example, the on-board charging device 11 can be a DCDC converter or a multi-functional on-board charging device that includes both a DCDC converter and an on-board charger (OBC). The VCU 13 can control the on-board charging device 11 to charge the low-voltage battery 12.

[0035] Optional, such as Figure 1BAs shown, the on-board charging device 11 is a DC-DC converter, which includes a voltage detection circuit 111 and a signal transmission circuit 112. The voltage detection circuit 111 detects the voltage of the low-voltage battery 12, and the signal transmission circuit 112 transmits a signal characterizing the state of the low-voltage battery 12 to the VCU 13. For example, when the DC-DC converter 11 is not charging the low-voltage battery 12, i.e., when the output current of the DC-DC converter 11 to the low-voltage battery 12 is 0, the voltage detection circuit 111 can detect the voltage of the low-voltage battery 12 through the circuit between the DC-DC converter 11 and the low-voltage battery 12, and obtain the state of the low-voltage battery 12 based on the voltage. Then, the signal characterizing the state of the low-voltage battery 12 is sent to the VCU 13 through the signal transmission circuit 112.

[0036] Optional, such as Figure 1C As shown, the on-board charging device 11 is a DC-DC converter. The voltage detection circuit 111 and signal transmission circuit 112 are configured externally to the DC-DC converter 11. Alternatively, the voltage detection circuit 111 and signal transmission circuit 112 can be configured externally to the low-voltage battery 12. For example, the voltage detection circuit 111 can be electrically connected to the low-voltage battery 12 at low voltage, and the signal transmission circuit 112 is connected to the VCU 13 via the vehicle bus. For instance, when the DC-DC converter 11 is not charging the low-voltage battery 12, i.e., when the output current from the DC-DC converter 11 to the low-voltage battery 12 is 0, the voltage detection circuit 111 can detect the voltage of the low-voltage battery 12 through the circuit between the DC-DC converter 11 and the low-voltage battery 12, and determine the state of the low-voltage battery 12 based on this voltage. Then, a signal characterizing the state of the low-voltage battery 12 is sent to the VCU 13 through the signal transmission circuit 112.

[0037] Optionally, VCU13 can also be configured outside of the low-voltage power supply system 10, and VCU13, the low-voltage power supply system 10 and the low-voltage electrical equipment 20 are connected via a vehicle bus.

[0038] In this embodiment, a fuse can be configured on the busbar between the on-board charging device 11 and the low-voltage battery 12. A fuse is an overcurrent protector; its principle is that when the current exceeds a specified threshold for a period of time, the heat generated by the fuse itself melts the fusible element, thereby breaking the circuit. When the on-board charging device 11 malfunctions, the low-voltage battery 12 provides power to melt the fuse, thus separating the malfunctioning on-board charging device 11 from the low-voltage battery 12. This avoids the safety risk of the low-voltage battery 12 losing power due to the malfunction of the on-board charging device 11, preventing the low-voltage electrical equipment 20 from obtaining normal operating voltage. However, when the low-voltage battery 12 has insufficient power to melt the fuse, the aforementioned safety risk cannot be avoided. Specifically, when the on-board charging device 11 malfunctions, the low-voltage battery 12 has insufficient power to melt the fuse, therefore the low-voltage battery 12 cannot be separated from the malfunctioning on-board charging device 11 in time, causing the output voltage of the low-voltage battery to drop rapidly, leading to safety problems for the vehicle. Therefore, in order to effectively avoid the safety risks caused by the malfunction of the on-board charging equipment 11, this application provides a vehicle control method, which can be found in the following details. Figure 2 Explanation.

[0039] Please see Figure 2 , Figure 2 This is a flowchart illustrating a vehicle control method provided in an embodiment of this application. This method can be based on... Figure 1A , Figure 1B and Figure 1C The low-voltage power supply system 10 is implemented in the method, which includes, but is not limited to, the following steps:

[0040] Step S201: The voltage detection circuit detects the voltage of the low-voltage battery.

[0041] For example, when the on-board charging equipment is not charging the low-voltage battery, that is, when the output current of the on-board charging equipment to the low-voltage battery is 0, the voltage detection circuit can detect the voltage across the low-voltage battery through the circuit between the on-board charging equipment and the low-voltage battery.

[0042] Optionally, the voltage detection circuit can obtain the corresponding state of charge (SOC) based on the detected voltage of the low-voltage battery. That is, the voltage detection circuit obtains a signal characterizing the state of the low-voltage battery, and the signal transmission circuit sends the signal to the VCU.

[0043] Optionally, the voltage detection circuit can send the detected low-voltage battery voltage to the calculation and analysis circuit. The calculation and analysis circuit obtains the corresponding SOC based on the low-voltage battery voltage, that is, it obtains a signal characterizing the state of the low-voltage battery. Then, the signal transmission circuit sends this signal to the VCU. Optionally, the calculation and analysis circuit can be electrically connected to the voltage detection circuit and the signal transmission circuit at low voltage.

[0044] In this embodiment, the voltage detection circuit and the signal transmission circuit can be as described above. Figure 1B The circuitry configured in the on-board charging equipment (i.e., DC-DC converter) can also be as described above. Figure 1C The circuitry is designed independently of the on-board charging device (i.e., DC-DC converter); in addition, the calculation and analysis circuitry can be either integrated into the DC-DC converter or designed independently of it.

[0045] Step S202: The VCU receives a signal representing the state of the low-voltage battery sent by the signal transmission circuit.

[0046] Specifically, the VCU analyzes the received signal representing the state of the low-voltage battery. The analysis result can be one of two cases: one is that the VCU analyzes and determines that the low-voltage battery is in a discharged state, as shown in steps S203-S206; the other is that the VCU analyzes and determines that the low-voltage battery is in a non-discharged state, as shown in steps S207-S208.

[0047] Step S203: The VCU determines that the low-voltage battery is in a discharged state.

[0048] Specifically, the VCU determines that the low-voltage battery is in a depleted state based on the signal characterizing the state of the low-voltage battery. Optionally, the depleted state is when the charge of the low-voltage battery is less than a preset threshold. Optionally, when the charge of the low-voltage battery is less than the preset threshold, the charge of the low-voltage battery is insufficient to blow the fuse between the on-board charging equipment and the low-voltage battery.

[0049] In this embodiment, a reference comparison value (such as the aforementioned preset threshold) can be pre-configured in the VCU to measure whether the low-voltage battery is in a discharged state or not. The aforementioned preset threshold is determined based on the performance parameters of the low-voltage battery, such as, but not limited to, open-circuit voltage, battery capacity, battery energy, energy density, and internal resistance. For ease of understanding, examples are provided below.

[0050] Case 1: If the State of Charge (SOC) is less than or equal to a preset first threshold, the low-voltage battery can be determined to be in a discharged state; if the SOC is greater than the first threshold, the low-voltage battery can be determined to be in a non-discharged state. For example, if the voltage capacity of the low-voltage battery is 1 million mAh, and it takes 50,000 mAh of power to blow the fuse between the on-board charger and the low-voltage battery, since 50,000 mAh is 5% of 100 mAh, the first threshold can be set to 5%. Therefore, if the SOC is less than or equal to 5%, the low-voltage battery cannot blow the fuse between the on-board charger and the low-voltage battery; if the SOC is greater than 5%, the low-voltage battery can blow the fuse between the on-board charger and the low-voltage battery.

[0051] Case 2: The VCU can determine the remaining charge of the low-voltage battery based on the State of Charge (SOC). If the remaining charge is less than or equal to a preset second threshold, the low-voltage battery is considered to be in a depleted state; if the remaining charge is greater than the second threshold, the low-voltage battery is considered to be in a non-depleted state. For example, if it takes 50,000 mAh to blow the fuse between the on-board charger and the low-voltage battery, then the second threshold can be set to 50,000 mAh. Therefore, if the remaining charge is less than or equal to 50,000 mAh, the low-voltage battery cannot blow the fuse between the on-board charger and the low-voltage battery; if the remaining charge is greater than 50,000 mAh, the low-voltage battery can blow the fuse between the on-board charger and the low-voltage battery.

[0052] Case 3: If the amount of electricity consumed by the low-voltage battery per unit time is greater than or equal to a preset third threshold, the low-voltage battery can be determined to be in a depleted state. If the amount of electricity consumed by the low-voltage battery per unit time is less than the third threshold, the low-voltage battery can be determined to be in a non-depleted state. For example, if the voltage capacity of the low-voltage battery is 1 million mAh and the remaining capacity is 900,000 mAh, and it takes 100,000 mAh of electricity to blow the fuse between the on-board charger and the low-voltage battery, and the low-voltage battery consumes 100,000 mAh of electricity in 1 second, the power consumption rate is too fast, and the power will be consumed to the point that the fuse between the on-board charger and the low-voltage battery cannot be blown within 8 seconds. In this case, the third threshold can be set to 50,000 mAh, the power consumption rate is slower, and it will take at least 16 seconds to consume the power to the point that the fuse cannot be blown. Therefore, if the low-voltage battery consumes more than or equal to 50,000 mAh per unit time, the low-voltage battery will not be able to blow the fuse between the on-board charging equipment and the low-voltage battery. If the low-voltage battery consumes less than 50,000 mAh per unit time, the low-voltage battery will be able to blow the fuse between the on-board charging equipment and the low-voltage battery.

[0053] Optionally, the battery detection circuit can also use the detected voltage of the low-voltage battery as a signal characterizing the state of the low-voltage battery, and send the signal to the VCU through a signal transmission circuit. The VCU can then determine whether the low-voltage battery is in a discharged state or not based on the signal. This application does not limit the method and parameters used to determine whether the low-voltage battery is in a discharged state or not.

[0054] Optionally, a reference comparison value (such as the aforementioned preset threshold) can be configured in the voltage detection circuit or calculation analysis circuit to measure whether the low-voltage battery is in a discharged state or not, thereby obtaining a signal indicating whether the low-voltage battery is in a discharged state or not, and sending the signal to the VCU through the signal transmission circuit; the VCU can directly confirm whether the low-voltage battery is in a discharged state or not based on the signal. The embodiments of this application do not limit the execution device for determining whether the low-voltage battery is in a discharged state or not.

[0055] Step S204: The VCU configures the motor controller to limit the vehicle's speed.

[0056] Specifically, the VCU can send commands to the motor controller to control gear shifting, throttle, or braking, etc., and the motor controller drives the vehicle motor according to these commands to limit the vehicle's speed. For example, if the vehicle's speed is 80 kilometers per hour, when the VCU determines that the low-voltage battery is depleted, the VCU can send a command to the motor controller to control the speed to 40 kilometers per hour, and the motor controller will drive the vehicle motor according to the command to limit the vehicle's speed to less than or equal to 40 kilometers per hour; or, when the VCU determines that the low-voltage battery is depleted, the VCU can send a braking command to the motor controller, and the motor controller will control the vehicle motor to stop working to stop the vehicle.

[0057] Step S205: The VCU controls the on-board charging equipment to charge the low-voltage battery so that the low-voltage battery is removed from the depleted state.

[0058] Optionally, if the on-board charging equipment is a DC-DC converter, then the VCU controls the on-board charging equipment to charge the low-voltage battery.

[0059] Optionally, if the on-board charging device is a multi-functional on-board charging device, then the VCU controls the DC-DC converter in the on-board charging device to charge the low-voltage battery.

[0060] Below are two optional charging methods for removing low-voltage batteries from a discharged state:

[0061] Option 1: The VCU controls the on-board charging equipment to continuously charge the low-voltage battery. Simultaneously, it monitors the battery's charge level at a preset frequency. When the battery's charge is sufficient to blow the fuse connecting the on-board charging equipment and the low-voltage battery, the VCU considers the low-voltage battery to be out of a depleted state. For example, monitoring at a frequency of once per minute, if the remaining charge of the low-voltage battery exceeds the aforementioned preset second threshold, it is considered that the battery's charge is sufficient to blow the fuse connecting the on-board charging equipment and the low-voltage battery, meaning the low-voltage battery is out of a depleted state.

[0062] Option 2 involves the VCU controlling the on-board charging equipment to charge the low-voltage battery for a target duration to remove it from a depleted state. The target duration can be determined based on one or more of the following: the low-voltage battery's power consumption per unit time, the on-board equipment's charging amount per unit time, and a preset target battery level. For example, the VCU first determines the current battery level, the on-board charging speed, and the target battery level. When the battery level reaches the target level, it provides sufficient power to fuse the circuit breaker between the battery and the on-board charging equipment. Then, the VCU calculates the difference between the target and current battery levels and divides this difference by the charging speed to obtain the target duration. When the charging time reaches the target duration, the battery level is sufficient to fuse the circuit breaker, thus removing the battery from a depleted state.

[0063] Optionally, the target duration can also be a pre-set time length based on the charging patterns of a large number of vehicles, such as 5 minutes.

[0064] Optionally, the charging speed of the on-board charging equipment can be a parameter configured in the VCU during vehicle production, or it can be the current charging speed of the on-board charging equipment detected in real time.

[0065] In this embodiment of the application, by charging the low-voltage battery, the low-voltage battery can be activated, thereby reducing the voltage corresponding to the internal resistance of the low-voltage battery and increasing the output voltage of the low-voltage battery. When the output voltage of the low-voltage battery increases to a certain extent, the fuse between the on-board charging equipment and the low-voltage battery can be blown, that is, the low-voltage battery is out of the depleted state.

[0066] Step S206: The VCU configures the motor controller to remove the speed limit on the vehicle.

[0067] Specifically, when the low-voltage battery is no longer in a discharged state, the VCU can send commands to the motor controller to control gear position, throttle, or brakes. The motor controller then drives the vehicle motor according to these commands to remove the speed limit on the vehicle, allowing it to drive normally. For example, if the vehicle stops driving after the VCU configures the motor controller in step S204, when the low-voltage battery is no longer in a discharged state, the VCU can send a start command to the motor controller. The motor controller then drives the vehicle motor according to these commands to start driving the vehicle.

[0068] Optionally, the voltage at which the on-board charging device charges the low-voltage battery when the vehicle is in normal driving condition (i.e., without speed restrictions) is greater than the voltage at which the on-board charging device charges the low-voltage battery when the vehicle's speed is restricted. For example, after step S206, the voltage at which the on-board charging device charges the low-voltage battery is greater than the voltage at which the on-board charging device charges the low-voltage battery in step S205. This avoids situations where the low-voltage battery is severely depleted, and the excessive charging current leads to low-voltage battery failure or a shortened lifespan.

[0069] In this embodiment, after the low-voltage battery is out of the depleted state, the VCU releases the speed limit on the vehicle. If the VCU detects a fault in the on-board charging equipment at this time, it can send a command to the low-voltage battery to blow the fuse between the on-board charging equipment and the low-voltage battery. In response to the command, the low-voltage battery provides power to blow the fuse, thereby disconnecting the faulty on-board charging equipment from the low-voltage power supply system and avoiding the safety risk of power loss for the low-voltage battery and low-voltage electrical equipment.

[0070] Optionally, after the low-voltage battery is out of the depleted state, the VCU releases the speed limit on the vehicle. If the low-voltage battery detects a fault in the on-board charging equipment at this time, it provides power to blow the aforementioned fuse, thereby disconnecting the faulty on-board charging equipment from the low-voltage power supply system and avoiding the safety risk of power loss for the low-voltage battery and low-voltage electrical equipment.

[0071] Step S207: The VCU determines that the low-voltage battery is not in a discharged state.

[0072] Specifically, the VCU determines that the low-voltage battery is in a non-discharged state based on the signals that characterize the state of the low-voltage battery; the non-discharged state is the state in which the charge of the low-voltage battery is greater than or equal to the preset threshold.

[0073] Step S208: The VCU controls the on-board charging equipment to charge the low-voltage battery.

[0074] Specifically, when the low-voltage battery is not in a discharged state, the VCU can also control the on-board charging equipment to charge the low-voltage battery, allowing the vehicle to run normally.

[0075] Optionally, the voltage at which the on-board charging device charges the low-voltage battery when the vehicle is in normal driving condition (i.e., without speed restrictions) is greater than the voltage at which the on-board charging device charges the low-voltage battery when the vehicle's speed is restricted; for example, the voltage at which the on-board charging device charges the low-voltage battery in step S208 is greater than the voltage at which the on-board charging device charges the low-voltage battery in step S205. This avoids situations where the low-voltage battery is in a severely depleted state, and the excessive charging current leads to low-voltage battery failure or a shortened lifespan.

[0076] exist Figure 2 In the described method, when the low-voltage battery is in a discharged state, the VCU limits the vehicle's speed and controls the on-board charging equipment to charge the low-voltage battery, thereby relieving it from the discharged state. Once the low-voltage battery is out of the discharged state, the VCU then releases the speed limit. On the one hand, if the on-board charging equipment malfunctions before the low-voltage battery is out of the discharged state, causing the battery to lose power, the vehicle will not experience serious safety issues because the speed has already been limited. On the other hand, if the on-board charging equipment malfunctions after the low-voltage battery is out of the discharged state, it will not cause the battery to lose power, thus preventing any safety problems. In summary, the embodiments of this application can significantly improve vehicle safety during driving.

[0077] Please see Figure 3 , Figure 3 This is a schematic flowchart of another vehicle control method provided in an embodiment of this application. This method can be applied to... Figure 1A , Figure 1B and Figure 1C The method includes, but is not limited to, the following steps: MCU14.

[0078] S501: The MCU receives the first instruction.

[0079] Specifically, when the VCU determines that the low-voltage battery is in a depleted state, it can send a first instruction to the MCU. Optionally, this depleted state means that the low-voltage battery's charge level is less than a preset threshold. Optionally, when the low-voltage battery's charge level is less than the aforementioned preset threshold, the low-voltage battery's charge level is insufficient to trip the fuse connecting the on-board charging equipment and the low-voltage battery. For an explanation of how the VCU determines that the low-voltage battery is in a depleted state, please refer to [link to documentation]. Figure 2 The explanation of S203. The first instruction is, for example, an instruction used to control the gear, accelerator, or brake.

[0080] S502: The MCU limits the vehicle's speed according to the first instruction.

[0081] In some embodiments, the MCU can drive the vehicle motor according to a first instruction to limit the vehicle's speed.

[0082] In some embodiments, the MCU can control the vehicle to decelerate according to a first instruction. For example, if the vehicle is traveling at 80 km / h, when the VCU determines that the low-voltage battery is in a depleted state, the VCU can send a first instruction to the MCU to control the driving speed to 40 km / h. The MCU drives the vehicle motor according to the first instruction to limit the vehicle's driving speed to less than or equal to 40 km / h.

[0083] In other embodiments, the MCU can control the vehicle to stop driving according to a first instruction. For example, when the VCU determines that the low-voltage battery is in a depleted state, the VCU can send a first braking instruction to the MCU, and the MCU can control the vehicle motor to stop working according to the first instruction to stop the vehicle from driving.

[0084] S503: MCU receives the second instruction.

[0085] Specifically, when the VCU determines that the low-voltage battery is in a discharged state, the VCU can control the on-board charging equipment to charge the low-voltage battery, thereby removing it from the discharged state. Then, the VCU can send a second instruction to the MCU. For an explanation of how the VCU controls the on-board charging equipment to charge the low-voltage battery to remove it from the discharged state, please refer to [link to relevant documentation]. Figure 2 The explanation of S205. The second instruction is, for example, an instruction used to control the gear, accelerator, or brake.

[0086] S504: The MCU releases the speed limit on the vehicle according to the second instruction.

[0087] In some embodiments, the MCU can drive the vehicle motor according to the second instruction to remove the speed limit of the vehicle in S502, and the vehicle can drive normally.

[0088] For example, the MCU controls the vehicle motor to stop working according to the first instruction, so that the vehicle stops moving. Then, when the low-voltage battery is discharged from the depleted state, the VCU sends a second instruction to the MCU to start, and the MCU drives the vehicle motor to start moving according to the second instruction.

[0089] The methods of the embodiments of this application have been described in detail above, and the apparatus of the embodiments of this application is provided below.

[0090] Please see Figure 4 , Figure 4This is a schematic diagram of a VCU (Vehicle Control Unit) provided in an embodiment of this application. The VCU is located inside a vehicle, which also includes a low-voltage battery, a motor controller, and an on-board charging device. The VCU 300 may include a determining unit 301, a first configuration unit 302, a charging unit 303, and a second configuration unit 304. Detailed descriptions of each unit are as follows:

[0091] Determining unit 301 is used to determine that the low-voltage battery is in a discharged state;

[0092] The first configuration unit 302 is used to configure the motor controller to limit the vehicle's speed.

[0093] Charging unit 303 is used to control the on-board charging equipment to charge the low-voltage battery so that the low-voltage battery is removed from the depleted state.

[0094] The second configuration unit 304 is used to configure the motor controller to remove the speed limit on the vehicle.

[0095] As can be seen, when the low-voltage battery is in a discharged state, the vehicle controller limits the vehicle's speed; once the low-voltage battery is out of the discharged state, the vehicle controller releases the speed limit. Therefore, when the low-voltage battery is in a discharged state, if the on-board charging equipment malfunctions, the low-voltage battery will lose power. Because the vehicle's speed is limited, the safety risk is relatively small. Conversely, when the low-voltage battery is out of the discharged state, if the on-board charging equipment malfunctions, the low-voltage battery will not lose power, thus significantly improving vehicle safety during driving.

[0096] In one alternative approach, the depleted state is defined as the state in which the charge of the low-voltage battery is less than a preset threshold.

[0097] It can be seen that measuring whether a low-voltage battery is in a depleted state by the relative magnitude of its charge level to a preset threshold is a simple and efficient method.

[0098] In another alternative, when the charge of the low-voltage battery is less than a preset threshold, the charge of the low-voltage battery is insufficient to blow the fuse between the on-board charging device and the low-voltage battery.

[0099] As can be seen, when the low-voltage battery is out of the depleted state, if the on-board charging equipment malfunctions, the low-voltage battery can provide power to fuse the fuse between the on-board charging equipment and the low-voltage battery, thus disconnecting the faulty on-board charging equipment from the low-voltage battery in time. Therefore, the low-voltage battery will not lose power, effectively improving the vehicle's safety performance.

[0100] In another alternative, the charging unit 303 is specifically used to control the on-board charging device to charge the low-voltage battery for a target duration so that the low-voltage battery is removed from the depleted state. The target duration is a preset time length, or a duration determined based on one or more of the following: the power consumption of the low-voltage battery per unit time, the charging amount of the on-board charging device per unit time, and the preset target power.

[0101] As can be seen, the specific charging time is the target duration for the low-voltage battery. The low-voltage battery is considered to have left the depleted state after the preset charging time, rather than continuously detecting whether the vehicle is in a depleted state in real time. This avoids the large computational overhead caused by multiple detections and also avoids the shortened lifespan of related circuits caused by multiple detections.

[0102] In another alternative embodiment, the vehicle includes a voltage detection circuit and a signal transmission circuit; the VCU300 further includes:

[0103] The receiving unit is configured to receive a signal sent by the signal transmission circuit indicating that the low-voltage battery is in the state of being ...

[0104] In another alternative embodiment, the on-board charging device is a DC-DC converter, and the voltage detection circuit and the signal transmission circuit are configured in the DC-DC converter.

[0105] It can be seen that the voltage detection circuit and signal transmission circuit can be configured in the DC-DC converter. On the one hand, some lines in the DC-DC converter can be reused, avoiding excessive circuit complexity; on the other hand, because it is designed in the DC-DC converter, it does not need to occupy space outside the DC-DC converter, thus improving the space utilization of the device.

[0106] In another alternative embodiment, when the vehicle's speed is limited, the voltage at which the on-board charging device charges the low-voltage battery is lower than the voltage at which the on-board charging device charges the low-voltage battery when the vehicle's speed is not limited. This avoids situations where excessive charging current could damage the battery or reduce its lifespan when the low-voltage battery is severely depleted.

[0107] It should be noted that the implementation of each operation can also be referenced accordingly. Figure 2 and Figure 3 The corresponding description of the method embodiments shown.

[0108] Please see Figure 5 , Figure 5This is a schematic diagram of another VCU structure provided in this application embodiment. The VCU is located inside a vehicle, which also includes a low-voltage battery, a motor controller, and an on-board charging device. The VCU 400 may include a processor 401, a memory 402, and a communication interface 403, which are interconnected via a bus.

[0109] The memory 402 includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or compact disc read-only memory (CD-ROM). The memory 402 is used to store related computer programs and data. The communication interface 403 is used to receive and send data.

[0110] Processor 401 can be one or more central processing units (CPUs). If processor 401 is a CPU, the CPU can be a single-core CPU or a multi-core CPU.

[0111] The processor 401 in VCU400 can be used to read the computer program code stored in memory 402 and perform the following operations:

[0112] It is determined that the low-voltage battery is in a discharged state;

[0113] The motor controller is configured to limit the vehicle's speed;

[0114] Control the on-board charging equipment to charge the low-voltage battery so that the low-voltage battery is removed from the depleted state;

[0115] The motor controller is configured to remove the speed limit on the vehicle.

[0116] In one alternative approach, the depleted state is defined as the state in which the charge of the low-voltage battery is less than a preset threshold.

[0117] In another alternative, when the charge of the low-voltage battery is less than a preset threshold, the charge of the low-voltage battery is insufficient to blow the fuse between the on-board charging device and the low-voltage battery.

[0118] In another alternative embodiment, when the processor 401 controls the on-board charging device to charge the low-voltage battery so that the low-voltage battery is removed from the depleted state, the following specific actions are performed:

[0119] The on-board charging device is controlled to charge the low-voltage battery for a target duration so that the low-voltage battery is removed from the depleted state. The target duration is a preset time length, or a duration determined based on one or more of the following: the power consumption of the low-voltage battery per unit time, the charging amount of the on-board charging device per unit time, and the preset target power.

[0120] In another alternative embodiment, the vehicle includes a voltage detection circuit and a signal transmission circuit; before determining that the low-voltage battery is in a depleted state, the processor 401 is further configured to perform:

[0121] The signal transmission circuit receives a signal indicating that the low-voltage battery is in the discharged state, wherein the signal indicating that the low-voltage battery is in the discharged state is acquired by the voltage detection circuit.

[0122] In another alternative embodiment, the on-board charging device is a DC-DC converter, and the voltage detection circuit and the signal transmission circuit are configured in the DC-DC converter.

[0123] In another alternative, the voltage at which the on-board charging device charges the low-voltage battery when the vehicle's speed is limited is lower than the voltage at which the on-board charging device charges the low-voltage battery when the vehicle's speed is not limited.

[0124] It should be noted that the implementation of each operation can also be referenced accordingly. Figure 2 and Figure 3 The corresponding description of the method embodiments shown.

[0125] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of an MCU provided in an embodiment of this application. The MCU is located inside a vehicle, which also includes a VCU, a low-voltage battery, and on-board charging equipment. The MCU 600 is used to perform the following operations:

[0126] Receive the first instruction, wherein the first instruction is sent to the MCU600 by the VCU when it determines that the low-voltage battery is in a state of low power, and the state of low power is the state where the power of the low-voltage battery is less than a preset threshold.

[0127] The vehicle's speed is restricted according to the first instruction;

[0128] Receive the second instruction, which is sent by the VCU to the MCU600 after the VCU controls the on-board charging equipment to charge the low-voltage battery so that the low-voltage battery is out of the depleted state.

[0129] The speed limit on the vehicle is lifted according to the second instruction.

[0130] As can be seen, when the low-voltage battery is in a discharged state, the motor controller limits the vehicle's speed; once the low-voltage battery is out of the discharged state, the motor controller releases the speed limit. Therefore, when the low-voltage battery is discharged, a malfunction in the onboard charging equipment will cause the battery to lose power, but because the vehicle's speed is limited, the safety risk is relatively low. Conversely, when the low-voltage battery is out of the discharged state, a malfunction in the onboard charging equipment will not cause the battery to lose power, and therefore releasing the speed limit does not pose a significant safety risk. This significantly improves vehicle safety during driving and ensures that the vehicle travels at the user's desired speed, thus prioritizing user experience.

[0131] In one possible implementation, when the low-voltage battery's charge is less than a preset threshold, the low-voltage battery's charge is insufficient to blow the fuse between the on-board charging equipment and the low-voltage battery.

[0132] In some embodiments, the fuse is used to melt the fusible element when the current exceeds a preset current threshold. That is, when the current of the fuse exceeds the preset current threshold, the bus between the on-board charging equipment and the low-voltage battery will be disconnected.

[0133] It can be seen that when the low-voltage battery is in a discharged state, if the on-board charging equipment malfunctions, although the low-voltage battery cannot be separated from the malfunctioning on-board charging equipment in time, resulting in rapid power loss, the vehicle's safety risk is also small because the vehicle's driving speed is limited, thus significantly improving the vehicle's safety during driving.

[0134] In one possible implementation, limiting the vehicle's speed according to the first instruction includes: controlling the vehicle to decelerate according to the first instruction, or controlling the vehicle to stop moving according to the first instruction.

[0135] It should be noted that the implementation of each operation can also be referenced accordingly. Figure 2 and Figure 3 The corresponding description of the method embodiments shown.

[0136] This application embodiment also provides a chip system, which includes at least one processor, a memory, and an interface circuit. The memory, the interface circuit, and the at least one processor are interconnected via lines. The memory stores a computer program, and when the computer program is executed by the at least one processor, it implements... Figure 2 and Figure 3 The operations performed in the illustrated embodiment.

[0137] This application also provides a computer-readable storage medium storing a computer program that, when run on a processor, implements... Figure 2 and Figure 3 The operations performed in the illustrated embodiment.

[0138] This application also provides a computer program product that, when run on a processor, implements... Figure 2 and Figure 3 The operations performed in the illustrated embodiment.

[0139] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program using computer program-related hardware. The computer program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The aforementioned storage medium includes various media capable of storing computer program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A vehicle control method characterized by, The method is applied to a motor controller, the motor controller is arranged in a vehicle, the vehicle further comprises a vehicle controller, a low-voltage storage battery and a vehicle-mounted charging device, and the method comprises the following steps: receiving a first instruction, the first instruction being sent by the vehicle controller to the motor controller when the vehicle controller determines that the low-voltage storage battery is in a power shortage state, the power shortage state being a state in which the power of the low-voltage storage battery is less than a preset threshold value, and the power of the low-voltage storage battery being unable to melt a fuse between the vehicle-mounted charging device and the low-voltage storage battery when the power of the low-voltage storage battery is less than the preset threshold value; limiting the driving speed of the vehicle according to the first instruction; receiving a second instruction, the second instruction being sent by the vehicle controller to the motor controller after the vehicle controller controls the vehicle-mounted charging device to charge the low-voltage storage battery so as to make the low-voltage storage battery get rid of the power shortage state; removing the limitation on the driving speed of the vehicle according to the second instruction.

2. The method of claim 1, wherein, The step of limiting the driving speed of the vehicle according to the first instruction comprises the following steps: controlling the vehicle to decelerate according to the first instruction, or controlling the vehicle to stop driving according to the first instruction.

3. An electric machine controller characterized by The motor controller is arranged in a vehicle, the vehicle further comprises a vehicle controller, a low-voltage storage battery and a vehicle-mounted charging device, and the motor controller is used to perform the following operations: receiving a first instruction, the first instruction being sent by the vehicle controller to the motor controller when the vehicle controller determines that the low-voltage storage battery is in a power shortage state, the power shortage state being a state in which the power of the low-voltage storage battery is less than a preset threshold value, and the power of the low-voltage storage battery being unable to melt a fuse between the vehicle-mounted charging device and the low-voltage storage battery when the power of the low-voltage storage battery is less than the preset threshold value; limiting the driving speed of the vehicle according to the first instruction; receiving a second instruction, the second instruction being sent by the vehicle controller to the motor controller after the vehicle controller controls the vehicle-mounted charging device to charge the low-voltage storage battery so as to make the low-voltage storage battery get rid of the power shortage state; removing the limitation on the driving speed of the vehicle according to the second instruction.

4. The motor controller of claim 3, wherein, The step of limiting the driving speed of the vehicle according to the first instruction comprises the following steps:

5. A vehicle characterized by comprising: controlling the vehicle to decelerate according to the first instruction, or controlling the vehicle to stop driving according to the first instruction.

6. A computer storage medium, characterized in that The vehicle comprises a vehicle controller, a low-voltage storage battery, a vehicle-mounted charging device and a motor controller, and the motor controller is the motor controller of claim 3 or 4. The computer storage medium stores a computer program, and the computer program is executed by a processor to implement the method of claim 1 or 2.

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