Electric Steering Control Method, Device, Vehicle and Storage Medium

Abstract

The present invention provides an electric power steering control method, device, vehicle and storage medium, belonging to the technical field of new energy vehicles. The method includes: when the high-voltage electric power steering system loses high voltage, obtaining the real-time drive voltage of the high-voltage electric power steering system, starting the low-voltage emergency steering system, and recording the operation duration of the low-voltage emergency steering system; performing switching control on the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operation duration of the low-voltage emergency steering system, wherein the switching time between the high-voltage electric power steering system and the low-voltage emergency steering system is greater than a preset time threshold. The present invention can ensure that there is no frequent switching between the high-voltage electric power steering system and the low-voltage emergency steering system, and can prevent damage to the high-voltage steering controller due to excessive drive voltage of the high-voltage steering controller.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and particularly to an electric steering control method, device, vehicle and storage medium. Background Art

[0002] With the rapid development of new energy vehicles, the degree of electrification of vehicle component systems is getting higher and higher. In addition to the large drive motor system, many components have been made high-voltage and electrified. For example, high-voltage electric power steering, electric air compressor, high-voltage to low-voltage DC converter, high-voltage electric air conditioner, etc. Among them, electric power steering has become the mainstream solution for the steering system of new energy vehicles.

[0003] To ensure driving safety and meet regulatory requirements, the vehicle steering system adopts a dual-source solution, that is, high-voltage electric power steering plus low-voltage emergency steering assistance. Under normal circumstances, the vehicle uses high-voltage electric power steering to achieve vehicle steering assistance. When the high-voltage electric power steering system fails and shuts down due to a fault, the low-voltage emergency steering assistance is switched in to ensure that the driver can safely pull over during driving. In the control strategy of the existing electric steering system, when the drive voltage of the high-voltage electric power steering system is lower than the high-voltage undervoltage threshold, the high-voltage electric power steering system stops working, and the low-voltage emergency steering system starts to provide emergency steering assistance. When the drive voltage of the high-voltage electric power steering system returns to the high-voltage undervoltage threshold, it switches back to the high-voltage electric power steering system to work. This will cause the steering system to frequently switch back and forth between the high-voltage electric power steering system and the low-voltage emergency steering system, and the vehicle cannot obtain steering assistance from the high-voltage steering and the low-voltage emergency steering, affecting driving safety; if no switching is performed, it will cause the drive voltage of the high-voltage steering controller to be too high, damaging the high-voltage steering controller.

[0004] It can be seen that in the control strategy of the electric steering control system in the prior art, when the vehicle abnormally loses high voltage, there is frequent switching back and forth between the high- and low-voltage control systems, affecting driving safety, or if no switching is performed, it will cause the high-voltage electric power steering system, resulting in too high a drive voltage of the high-voltage steering controller and damaging the high-voltage steering controller. Summary of the Invention

[0005] In view of this, it is necessary to provide an electric steering control method, device, vehicle and storage medium to solve the technical problems in the control strategy of the electric steering control system in the prior art that when the vehicle abnormally loses high voltage, there is frequent switching back and forth between the high- and low-voltage control systems, affecting driving safety, or if no switching is performed, it will cause the high-voltage electric power steering system, resulting in too high a drive voltage of the high-voltage steering controller and damaging the high-voltage steering controller.

[0006] To solve the above technical problems, on the one hand, the present invention provides an electric steering control method, including:

[0007] When the high-voltage power supply of the high-voltage electric power steering system is lost, obtain the real-time driving voltage of the high-voltage electric power steering system, start the low-voltage emergency steering system, and record the operation duration of the low-voltage emergency steering system;

[0008] Based on the magnitude of the real-time driving voltage and the operation duration of the low-voltage emergency steering system, perform switching control on the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system, wherein the switching time between the high-voltage electric power steering system and the low-voltage emergency steering system is greater than a preset time threshold.

[0009] As a possible implementation manner of the present invention, in this implementation manner, the controlling the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operation duration of the low-voltage emergency steering system includes:

[0010] When the operation duration is less than or equal to the first operation duration, judge the magnitude relationship between the real-time driving voltage and the high-voltage undervoltage threshold;

[0011] When the real-time driving voltage is less than the preset high-voltage undervoltage threshold, maintain the continuous operation of the low-voltage emergency steering system and maintain the continuous shutdown of the high-voltage electric power steering system;

[0012] When the real-time driving voltage is greater than or equal to the preset high-voltage undervoltage threshold, control the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage.

[0013] As a possible implementation manner of the present invention, in this implementation manner, the controlling the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage includes:

[0014] When the real-time driving voltage is between the high-voltage undervoltage recovery threshold and the high-voltage overvoltage recovery threshold, judge whether the high-voltage electric power steering system has an abnormal loss of high voltage; wherein, the high-voltage undervoltage recovery threshold is greater than the high-voltage undervoltage threshold, and the high-voltage undervoltage recovery threshold is less than the high-voltage overvoltage recovery threshold;

[0015] When the high-voltage electric power steering system has an abnormal loss of high voltage, maintain the continuous operation of the low-voltage emergency steering system and maintain the continuous shutdown of the high-voltage electric power steering system;

[0016] When the high-voltage electric power steering system does not have an abnormal loss of high voltage, start the high-voltage electric power steering system and stop the low-voltage emergency steering system.

[0017] As a possible implementation of the present invention, in this implementation, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage includes:

[0018] When the real-time drive voltage is between the high-voltage overvoltage recovery threshold and the high-voltage overvoltage threshold, determine whether the high-voltage electric power steering system has an abnormal loss of high voltage; wherein, the high-voltage overvoltage threshold is greater than the high-voltage overvoltage recovery threshold;

[0019] When the high-voltage electric power steering system does not have an abnormal loss of high voltage, start the high-voltage electric power steering system and stop the low-voltage emergency steering system;

[0020] When the high-voltage electric power steering system has an abnormal loss of high voltage, maintain the continuous operation of the low-voltage emergency steering system, maintain the continuous shutdown of the high-voltage electric power steering system, and turn on the voltage consumption unit to reduce the real-time drive voltage.

[0021] As a possible implementation of the present invention, in this implementation, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage includes:

[0022] When the real-time drive voltage is greater than the high-voltage overvoltage threshold, maintain the continuous operation of the low-voltage emergency steering system, maintain the continuous shutdown of the high-voltage electric power steering system, and turn on the voltage consumption unit to reduce the real-time drive voltage.

[0023] As a possible implementation of the present invention, in this implementation, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operating duration of the low-voltage emergency steering system includes:

[0024] When the operating duration is greater than the first operating duration, stop the low-voltage emergency steering system and determine the magnitude relationship between the real-time drive voltage and the high-voltage undervoltage recovery threshold;

[0025] When the real-time drive voltage is greater than or equal to the high-voltage undervoltage recovery threshold, start the high-voltage electric power steering system;

[0026] When the real-time drive voltage is less than the high-voltage undervoltage recovery threshold, maintain the continuous shutdown of the high-voltage electric power steering system.

[0027] As a possible implementation of the present invention, before controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operating duration of the low-voltage emergency steering system, it includes:

[0028] When there is no need for power steering assistance, keep the high-voltage electric power steering system in a shutdown state.

[0029] On the other hand, the present invention also provides an electric power steering control device, including:

[0030] An information acquisition module, configured to obtain the real-time driving voltage of the high-voltage electric power steering system when the high voltage of the high-voltage electric power steering system drops, start the low-voltage emergency power steering system, and record the operation duration of the low-voltage emergency power steering system;

[0031] A control module, configured to perform switching control on the operating states of the high-voltage electric power steering system and the low-voltage emergency power steering system based on the magnitude of the real-time driving voltage and the operation duration of the low-voltage emergency power steering system, wherein the switching time between the high-voltage electric power steering system and the low-voltage emergency power steering system is greater than a preset time threshold.

[0032] On the other hand, the present invention also provides a vehicle, including a memory and a processor, wherein,

[0033] The memory is used to store programs;

[0034] The processor is coupled to the memory and is configured to execute the programs stored in the memory to implement the steps in the electric power steering control method in any of the above implementation manners.

[0035] On the other hand, the present invention also provides a computer-readable storage medium, configured to store computer-readable programs or instructions, and when the programs or instructions are executed by a processor, the steps in the electric power steering control method in any of the above implementation manners can be implemented.

[0036] The beneficial effects of the present invention are as follows: The electric power steering control method provided by the present invention, when the vehicle abnormally drops high voltage, obtains the real-time driving voltage of the high-voltage electric power steering system, starts the low-voltage emergency power steering system, and records the operation duration of the low-voltage emergency power steering system; controls the operating states of the high-voltage electric power steering system and the low-voltage emergency power steering system based on the magnitude of the real-time driving voltage and the operation duration of the low-voltage emergency power steering system. Compared with the prior art, instead of switching when the driving voltage of the high-voltage electric power steering system reaches the undervoltage recovery threshold, it considers whether the high-voltage electric power steering system can maintain operation for a long time, or whether the voltage of the high-voltage electric power steering system poses a safety hazard to the high-voltage steering controller. Further, by setting the switching time between the high-voltage electric power steering system and the low-voltage emergency power steering system to be greater than a preset time threshold, it can ensure that there is no frequent switching between the high-voltage electric power steering system and the low-voltage emergency power steering system, and can prevent damage to the high-voltage steering controller due to too high a driving voltage of the high-voltage steering controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0038] Figure 1 Schematic diagram of the high-voltage power distribution topology and dual-source steering connection of a vehicle provided by an embodiment of the present invention;

[0039] Figure 2 Schematic diagram of the high-voltage power distribution topology and dual-source steering connection of a vehicle under the high-voltage state provided by an embodiment of the present invention;

[0040] Figure 3 Schematic diagram of the reverse charging principle of the main drive motor provided by an embodiment of the present invention;

[0041] Figure 4 Schematic flow chart of an electric power steering control method provided by an embodiment of the present invention;

[0042] Figure 5 Schematic flow chart of the first electric power steering control strategy provided by an embodiment of the present invention;

[0043] Figure 6 Schematic flow chart of the second electric power steering control strategy provided by an embodiment of the present invention;

[0044] Figure 7 Schematic flow chart of the third electric power steering control strategy provided by an embodiment of the present invention;

[0045] Figure 8 Schematic flow chart of the fourth electric power steering control strategy provided by an embodiment of the present invention;

[0046] Figure 9 Schematic diagram of the structure of an electric power steering control device provided by an embodiment of the present invention;

[0047] Figure 10 Schematic diagram of the structure of a vehicle provided by an embodiment of the present invention. Detailed implementation manners

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0049] In the embodiments of the present invention, the descriptions such as "first" and "second" are only for descriptive purposes and cannot be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Therefore, the technical features defined with "first" and "second" may explicitly or implicitly include at least one such feature.

[0050] Reference to "embodiment" in this text means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0051] The present invention provides an electric power steering control method, device, vehicle, and storage medium, which will be described separately below.

[0052] First, for ease of explanation, as Figure 1 shown, a high-voltage power distribution topology and a dual-source steering connection schematic diagram of a vehicle are provided. When the vehicle is driving normally, the power battery system 101 controls the high-voltage power on and off of the power battery 102 through its internal negative contactor 103; controls the high-voltage power on and off of the high-voltage main drive motor controller 108 through the main drive circuit positive relay 105 in the high-voltage power distribution box 104, controls the high-voltage power on and off of the high-voltage electric power steering 110, electric air compressor 112, high-voltage to low-voltage DC module 114, and electric air-conditioning system 116 through the auxiliary drive circuit positive relay 106, and controls the high-voltage power on and off of the PTC system 117 through the PTC circuit positive relay 107. After successful high-voltage power on, the main drive motor controller 108 controls the operation of the main drive motor 109, the high-voltage steering controller 110 controls the operation of the high-voltage steering motor 111, the electric air compressor controller 112 controls the operation of the air compressor motor 113, and the DCDC high-voltage to low-voltage module 114 charges the low-voltage battery 115. The high-voltage electric power steering motor 111 and the low-voltage emergency steering motor 118 are coaxial. When the high-voltage steering assist fails, the low-voltage emergency steering controller 119 obtains 24V power from the low-voltage battery and controls the operation of the low-voltage emergency steering motor 118 to provide emergency steering assist.

[0053] When the vehicle is driving at high speed and the high-voltage power of the power battery drops abnormally, for example, the negative contactor 103 is disconnected due to the momentary break or accidental touch of the high-voltage emergency stop switch in the cab, or the vehicle control unit HCU resets due to external interference and sends a power-off command to the power battery system 101, but all the positive relays 105, 106, 107 inside the PDU maintain the state at the moment before power-off because the high-voltage loads of the whole vehicle are running and cannot be immediately disconnected for power-off, otherwise, it will cause relay adhesion caused by power-off with load. Figure 1The connection schematic diagram of the high-voltage power distribution topology and dual-source steering of a new energy vehicle will be transformed into Figure 2 , the power battery system 101 is disconnected from the vehicle high-voltage circuit and cannot provide a discharge and charging circuit. Due to the absence of high-voltage input, the terminal voltages of the support capacitors C1, C2, C3, and C4 at the input end of the rear-end high-voltage load controller will quickly drop below the undervoltage threshold of each controller bus, and the load controller reports a bus undervoltage fault and shuts down. For the steering system, the high-voltage electric power steering 110 and 111 fail, and the low-voltage emergency steering 118 and 119 are cut in to work. The main drive motor 109 (usually a permanent magnet synchronous motor) cannot suddenly drop to zero speed due to high-speed driving. The back electromotive force generated by the kinetic energy of the motor during the rotation of the motor forms a rectification circuit through the freewheeling diodes of the three-phase bridge circuit in the main drive motor controller 108 to charge the capacitor C1. C1 will also charge C2 and C3, which are connected in parallel through the closing of the positive relay 105 and 106 of the main drive and auxiliary drive circuits, as Figure 3 shown. When the voltage across C2 is charged to the high-voltage undervoltage recovery threshold and the high-voltage steering self-recovers, it will cause the low-voltage emergency steering to stop working. At the same time, since the back electromotive force ability cannot maintain the continuous operation of the high-voltage steering, the voltage across C2 will soon drop below the undervoltage threshold and the high-voltage undervoltage threshold again, and enter the shutdown mode again. The low-voltage emergency steering monitors that the high-voltage steering has stopped working and will enter again. In this way, the high- and low-voltage steering switches repeatedly until the back electromotive force generated by the speed of the main drive motor is not sufficient to charge the voltage of C2 to the high-voltage undervoltage recovery threshold. At this time, the vehicle completely loses the steering assist, posing a safety hazard. Based on this, the embodiment of the present invention provides an electric power steering control method, as Figure 4 shown, the electric power steering control method includes:

[0054] S401, when the high-voltage electric power steering system loses high voltage, obtain the real-time drive voltage of the high-voltage electric power steering system, start the low-voltage emergency steering system, and record the operation duration of the low-voltage emergency steering system;

[0055] S402, based on the magnitude of the real-time drive voltage and the operation duration of the low-voltage emergency steering system, perform switching control on the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system, wherein the switching time between the high-voltage electric power steering system and the low-voltage emergency steering system is greater than a preset time threshold.

[0056] In an embodiment of the present invention, based on the foregoing implementation scenario, during the operation of the vehicle, the real-time drive voltage of the high-voltage electric power steering system can be monitored through a sampling circuit and the vehicle CAN message, that is, the real-time terminal voltage of the C2 capacitor in the high-voltage steering controller. When the high-voltage electric power steering system loses high voltage, that is, when the real-time terminal voltage of the C2 capacitor is less than the preset high-voltage undervoltage threshold, the low-voltage emergency steering system is started, and at the same time, the operation duration of the low-voltage emergency steering system is recorded. Since the main drive motor cannot suddenly drop to zero speed due to high-speed driving at this time, the kinetic energy of the motor generates a back electromotive force during the rotation of the motor, which forms a rectifying circuit through the freewheeling diode of the three-phase bridge circuit in the main drive motor controller to charge the capacitor C1. C1 will also charge C2, C3, and C4 that are in a parallel relationship formed by the closing of the positive relay in the main drive and auxiliary drive circuits. Then, the real-time terminal voltage of C2 will gradually increase. To prevent frequent switching between the high-voltage electric power steering system and the low-voltage emergency steering system, it is necessary to control the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operating duration of the low-voltage emergency steering system, so as to ensure that the switching time between the high-voltage electric power steering system and the low-voltage emergency steering system is greater than the preset time threshold, and at the same time prevent the high-voltage electric power steering system from being damaged due to too high drive voltage.

[0057] As a possible implementation manner of the present invention, in this implementation manner, as Figure 5 shown, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operating duration of the low-voltage emergency steering system includes:

[0058] S501, when the operation duration is less than or equal to the first operation duration, determine the magnitude relationship between the real-time drive voltage and the high-voltage undervoltage threshold;

[0059] S502, when the real-time drive voltage is less than the preset high-voltage undervoltage threshold, maintain the continuous operation of the low-voltage emergency steering system and maintain the continuous shutdown of the high-voltage electric power steering system;

[0060] S503, when the real-time drive voltage is greater than or equal to the preset high-voltage undervoltage threshold, control the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage.

[0061] In the embodiment of the present invention, the high-voltage undervoltage threshold refers to the minimum driving voltage value at which the high-voltage electric power steering system can operate normally. After the vehicle abnormally loses high voltage, when the continuous operation duration of the low-voltage emergency steering system is less than or equal to the first operation duration (such as 60 seconds), the back electromotive force generated by the main drive motor speed charges the C2 capacitor. It is necessary to judge the magnitude relationship between the real-time terminal voltage of the C2 capacitor and the high-voltage undervoltage threshold. When the real-time terminal voltage of the C2 capacitor is less than the preset high-voltage undervoltage threshold, it means that the real-time terminal voltage of the C2 capacitor cannot start the operation of the high-voltage electric power steering system. At this time, it is necessary to maintain the continuous operation of the low-voltage emergency steering system and keep the high-voltage electric power steering system shut down. When the real-time terminal voltage of the C2 capacitor is greater than or equal to the preset high-voltage undervoltage threshold, it means that the real-time terminal voltage of the C2 capacitor is sufficient to start the high-voltage electric power steering system. However, to prevent the excessive real-time terminal voltage of the C2 capacitor from damaging the controller of the high-voltage electric power steering system, the high-voltage electric power steering system cannot be directly started at this time. It is necessary to judge how to control the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system according to the specific magnitude of the real-time terminal voltage of the C2 capacitor.

[0062] Further, as Figure 6 shown, controlling the operation states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage includes:

[0063] S601, when the real-time driving voltage is between the high-voltage undervoltage recovery threshold and the high-voltage overvoltage recovery threshold, judge whether the high-voltage electric power steering system has abnormally lost high voltage; wherein, the high-voltage undervoltage recovery threshold is greater than the high-voltage undervoltage threshold, and the high-voltage undervoltage recovery threshold is less than the high-voltage overvoltage recovery threshold;

[0064] S602, when the high-voltage electric power steering system has abnormally lost high voltage, maintain the continuous operation of the low-voltage emergency steering system and keep the high-voltage electric power steering system shut down;

[0065] S603, when the high-voltage electric power steering system has not abnormally lost high voltage, start the high-voltage electric power steering system and shut down the low-voltage emergency steering system.

[0066] In an embodiment of the present invention, the high-voltage undervoltage recovery threshold is the minimum drive voltage value at which the high-voltage electric power steering system recovers from the high-voltage shutdown state to the normal operating state. The high-voltage overvoltage recovery threshold refers to the maximum drive voltage value at which the high-voltage electric power steering system recovers from the high-voltage shutdown state to the normal operating state. When the applied drive voltage is between the high-voltage undervoltage recovery threshold and the high-voltage overvoltage recovery threshold, it indicates that the current drive voltage meets the requirements for the high-voltage electric power steering system to recover to the normal working state. However, before restoring the high-voltage electric power steering system to the startup state, it is necessary to determine whether the high-voltage electric power steering system has an abnormal loss of high voltage. Specifically, it can be determined whether there is an abnormal loss of high voltage based on the terminal voltage of C2 inside the high-voltage steering controller, the main drive motor speed, the state of the power battery negative relay, the state of the main drive circuit positive relay, and the state of the auxiliary drive circuit positive relay. For example, when the main drive motor speed is greater than the rated speed, the power battery negative relay is in the open state, and the main drive circuit positive relay and the auxiliary drive circuit positive relay are in the closed state, it is determined that the power battery has an abnormal power outage. At this time, the high-voltage electric power steering system has an abnormal loss of high voltage, and the high-voltage electric power steering system still cannot be restored. Instead, the low-voltage emergency steering system should be maintained to continue operating, and the high-voltage electric power steering system should continue to be shut down. If it is determined that the high-voltage electric power steering system does not have an abnormal loss of high voltage, the high-voltage electric power steering system can be started, and the low-voltage emergency steering system can be shut down.

[0067] Further, as Figure 7 shown, based on the magnitude of the real-time drive voltage, the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system are controlled, including:

[0068] S701, when the real-time drive voltage is between the high-voltage overvoltage recovery threshold and the high-voltage overvoltage threshold, determine whether the high-voltage electric power steering system has an abnormal loss of high voltage; where the high-voltage overvoltage threshold is greater than the high-voltage overvoltage recovery threshold;

[0069] S702, when the high-voltage electric power steering system does not have an abnormal loss of high voltage, start the high-voltage electric power steering system and shut down the low-voltage emergency steering system;

[0070] S703, when the high-voltage electric power steering system has an abnormal loss of high voltage, maintain the low-voltage emergency steering system to continue operating, maintain the high-voltage electric power steering system to continue shutting down, and turn on the voltage consumption unit to reduce the real-time drive voltage.

[0071] In the embodiment of the present invention, the high-voltage overvoltage threshold refers to the maximum safety threshold of the driving voltage of the high-voltage electric power steering system. When the driving voltage is greater than the high-voltage overvoltage threshold, there is a risk of damage to the high-voltage steering controller. When the real-time driving voltage is between the high-voltage overvoltage recovery threshold and the high-voltage overvoltage threshold, it is necessary to control the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system in combination with whether the high-voltage electric power steering system has an abnormal loss of high voltage. Specifically, when the high-voltage electric power steering system does not have an abnormal loss of high voltage, it means that the high-voltage electric power steering system can resume operation and maintain the operating state for a long time. Then, the high-voltage electric power steering system can be directly started, and the low-voltage emergency steering system can be shut down. However, when the high-voltage electric power steering system has an abnormal loss of high voltage, it means that even if the high-voltage electric power steering system is restored to the working state, it will continue to lose high voltage in a short time, and the high-voltage electric power steering system cannot continue to work. At this time, the high-voltage electric power steering system cannot be restored to the working state, and the low-voltage emergency steering system should be maintained to continue operating, and the high-voltage electric power steering system should be maintained to continue shutting down. Moreover, in order to prevent the back electromotive force generated by the rotation speed of the main drive motor from continuously charging the C2 capacitor and causing the terminal voltage of the C2 capacitor to be too high, damaging the high-voltage steering controller, the voltage consumption unit can be turned on to reduce the terminal voltage of the C2 capacitor. Specifically, the voltage consumption unit is Figure 1 the DC-DC unit shown. When the DC-DC unit operates, it can consume the terminal voltage of the capacitor C2, thereby reducing the driving voltage.

[0072] Furthermore, based on the magnitude of the real-time driving voltage, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system includes:

[0073] When the real-time driving voltage is greater than the high-voltage overvoltage threshold, maintain the low-voltage emergency steering system to continue operating, maintain the high-voltage electric power steering system to continue shutting down, and turn on the voltage consumption unit to reduce the real-time driving voltage.

[0074] In the embodiment of the present invention, following the foregoing embodiment, when the real-time driving voltage is greater than the high-voltage overvoltage threshold, it indicates that the terminal voltage of the C2 capacitor is already too high. At this time, regardless of whether the high-voltage electric power steering system has an abnormal loss of high voltage, the high-voltage electric power steering system cannot be directly restored to the working state. It is necessary to first discharge the C2 capacitor. The low-voltage emergency steering system should be maintained to continue operating, the high-voltage electric power steering system should be maintained to continue shutting down, and the voltage consumption unit should be turned on to reduce the real-time driving voltage.

[0075] As a possible implementation manner of the present invention, in this implementation manner, as Figure 8 shown, based on the magnitude of the real-time driving voltage and the operating duration of the low-voltage emergency steering system, controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system includes:

[0076] S801. When the running duration is greater than the first running duration, stop the low-voltage emergency steering system and determine the magnitude relationship between the real-time drive voltage and the high-voltage undervoltage recovery threshold.

[0077] S802. When the real-time drive voltage is greater than or equal to the high-voltage undervoltage recovery threshold, start the high-voltage electric power steering system.

[0078] S803. When the real-time drive voltage is less than the high-voltage undervoltage recovery threshold, maintain the high-voltage electric power steering system in a stopped state.

[0079] In the embodiment of the present invention, if the running duration of the low-voltage emergency steering system has exceeded the preset first running duration (such as 60 seconds), it indicates that the high-voltage electric power steering system has not been running for more than 60 seconds, and the low-voltage emergency steering system has reached the running limit time. The low-voltage emergency steering system needs to be shut down. At this time, only the magnitude relationship between the real-time drive voltage and the high-voltage undervoltage recovery threshold needs to be determined. When the real-time drive voltage is greater than or equal to the high-voltage undervoltage recovery threshold, the high-voltage electric power steering system can be directly started. When the real-time drive voltage is less than the high-voltage undervoltage recovery threshold, the high-voltage electric power steering system is maintained in a stopped state. Based on this, during the running time of the low-voltage emergency steering system, sufficient emergency steering assistance has been provided to the driver to facilitate the driver to pull over.

[0080] Further, before controlling the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the running duration of the low-voltage emergency steering system, it includes:

[0081] When there is no steering assistance requirement, maintain the high-voltage electric power steering system in a stopped state.

[0082] In the embodiment of the present invention, the steering assistance requirement can be an operation of the driver or the autonomous vehicle turning the steering wheel. For some special situations, such as when the vehicle only needs to drive straight, even if the vehicle abnormally loses high voltage and the high-voltage electric power steering system stops working, since the vehicle does not need to turn, the high-voltage electric power steering system can be maintained in a stopped state.

[0083] The electric steering control method provided by the present invention, when the vehicle abnormally loses high voltage, obtains the real-time drive voltage of the high-voltage electric steering system, starts the low-voltage emergency steering system, and records the operation duration of the low-voltage emergency steering system; controls the operation states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operation duration of the low-voltage emergency steering system. Compared with the prior art, instead of switching as soon as the drive voltage of the high-voltage electric steering system reaches the undervoltage recovery threshold, it considers whether the high-voltage electric steering system can maintain operation for a long time or whether the voltage of the high-voltage electric steering system poses a safety hazard to the high-voltage steering controller. Further, by setting the switching time between the high-voltage electric steering system and the low-voltage emergency steering system to be greater than the preset time threshold, it can ensure that there is no frequent switching between the high-voltage electric steering system and the low-voltage emergency steering system, and can prevent damage to the high-voltage steering controller due to too high a drive voltage of the high-voltage steering controller.

[0084] To better implement the electric steering control method in the embodiments of the present invention, correspondingly, based on the electric steering control method, as Figure 9 shown, the embodiments of the present invention further provide an electric steering control device. The electric steering control device 900 includes:

[0085] An information acquisition module 901, configured to obtain the real-time drive voltage of the high-voltage electric steering system, start the low-voltage emergency steering system, and record the operation duration of the low-voltage emergency steering system when the high-voltage electric steering system loses high voltage;

[0086] A control module 902, configured to perform switching control on the operation states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time drive voltage and the operation duration of the low-voltage emergency steering system, wherein the switching time between the high-voltage electric steering system and the low-voltage emergency steering system is greater than the preset time threshold.

[0087] The above-mentioned electric steering control device 900 provided by the above embodiment can implement the technical solutions described in the above embodiment of the electric steering control method. The specific implementation principles of the above-mentioned modules or units can be referred to the corresponding content in the above embodiment of the electric steering control method, which will not be elaborated here.

[0088] As Figure 10 shown, the present invention also correspondingly provides a vehicle 1000. The vehicle 1000 includes a processor 1001, a memory 1002, and a display 1003. Figure 10 Only some components of the vehicle 1000 are shown, but it should be understood that it is not required to implement all the shown components, and more or fewer components can be alternatively implemented.

[0089] In some embodiments, the processor 1001 may be a central processing unit (CPU), a microprocessor, or other data processing chips, which are used to run the program code stored in the memory 1002 or process data, such as the electric power steering control method in the present invention.

[0090] In some embodiments, the processor 1001 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processor 1001 may be local or remote. In some embodiments, the processor 1001 may be implemented on a cloud platform. In one embodiment, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-cloud, etc., or any combination thereof.

[0091] In some embodiments, the memory 1002 may be an internal storage unit of the vehicle 1000, such as the hard disk or memory of the vehicle 1000. In some other embodiments, the memory 1002 may also be an external storage device of the vehicle 1000, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. equipped on the vehicle 1000.

[0092] Furthermore, the memory 1002 may also include both the internal storage unit of the vehicle 1000 and the external storage device. The memory 1002 is used to store the application software installed in the vehicle 1000 and various types of data.

[0093] In some embodiments, the display 1003 may be an LED display, a liquid crystal display, a touch liquid crystal display, and an OLED (Organic Light-Emitting Diode) toucher, etc. The display 1003 is used to display the information of the vehicle 1000 and to display a visual user interface. The components 1001-1003 of the vehicle 1000 communicate with each other through a system bus.

[0094] In one embodiment, when the processor 1001 executes the electric power steering control program in the memory 1002, the following steps may be implemented:

[0095] When the high-voltage electric power steering system loses high voltage, obtain the real-time drive voltage of the high-voltage electric power steering system, start the low-voltage emergency steering system, and record the operation duration of the low-voltage emergency steering system;

[0096] Based on the magnitude of the real-time driving voltage, the operating duration of the low-voltage emergency steering system controls the operating states of the high-voltage electric power steering system and the low-voltage emergency steering system, wherein the switching time between the high-voltage electric power steering system and the low-voltage emergency steering system is greater than a preset time threshold.

[0097] It should be understood that when the processor 1001 executes the electric power steering control program in the memory 1002, in addition to the above functions, other functions can also be realized. For specific details, reference can be made to the descriptions of the corresponding method embodiments above.

[0098] Correspondingly, an embodiment of the present invention further provides a computer-readable storage medium. The computer-readable storage medium is used to store computer-readable programs or instructions. When the programs or instructions are executed by a processor, the steps or functions in the electric power steering control method provided by the above-mentioned method embodiments can be realized.

[0099] Those skilled in the art can understand that all or part of the processes for implementing the methods in the above embodiments can be completed by instructing relevant hardware (such as a processor, a controller, etc.) through a computer program. The computer program can be stored in a computer-readable storage medium. Among them, the computer-readable storage medium is a magnetic disk, an optical disk, a read-only memory, or a random access memory, etc.

[0100] The above has introduced in detail the electric power steering control method, device, vehicle, and storage medium provided by the present invention. Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present invention; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. An electric power steering control method, characterized in that: include: When the high-voltage electric steering system loses high voltage, obtaining the real-time driving voltage of the high-voltage electric steering system, starting the low-voltage emergency steering system, and recording the operation time of the low-voltage emergency steering system; Switching and controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operating time of the low-voltage emergency steering system, wherein the switching time between the high-voltage electric steering system and the low-voltage emergency steering system is greater than a preset time threshold; The controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operating duration of the low-voltage emergency steering system includes: When the operation duration is less than or equal to the first operation duration, determining the magnitude relationship between the real-time driving voltage and the high-voltage undervoltage threshold; When the real-time driving voltage is less than the preset high-voltage undervoltage threshold, the low-voltage emergency steering system is maintained to continue to operate, and the high-voltage electric steering system is maintained to continue to shut down; When the real-time driving voltage is greater than or equal to the preset high-voltage undervoltage threshold, the operating states of the high-voltage electric steering system and the low-voltage emergency steering system are controlled based on the magnitude of the real-time driving voltage; The controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage includes: When the real-time driving voltage is between the high-voltage undervoltage recovery threshold and the high-voltage overvoltage recovery threshold, it is judged whether the high-voltage electric steering system is abnormally losing high voltage; wherein the high-voltage undervoltage recovery threshold is greater than the high-voltage undervoltage threshold, and the high-voltage undervoltage recovery threshold is less than the high-voltage overvoltage recovery threshold; When the high-voltage electric steering system is abnormally high-voltage, the low-voltage emergency steering system is maintained to continue to operate, and the high-voltage electric steering system is maintained to continue to be shut down; When the high-voltage electric steering system is not abnormally high-voltage, the high-voltage electric steering system is started and the low-voltage emergency steering system is shut down.

2. The electric power steering control method according to claim 1, characterized in that: The controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage includes: When the real-time driving voltage is between the high-voltage overvoltage recovery threshold and the high-voltage overvoltage threshold, it is determined whether the high-voltage electric steering system is abnormally dropping high voltage; wherein the high-voltage overvoltage threshold is greater than the high-voltage overvoltage recovery threshold; When the high-voltage electric steering system is not abnormally high-voltage, starting the high-voltage electric steering system and stopping the low-voltage emergency steering system; When the high-voltage electric steering system abnormally drops high voltage, the low-voltage emergency steering system is maintained to continue to operate, the high-voltage electric steering system is maintained to continue to be shut down, and the voltage consumption unit is turned on to reduce the real-time driving voltage.

3. The electric power steering control method according to claim 1, characterized in that: The controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage includes: When the real-time driving voltage is greater than the high-voltage overvoltage threshold, the low-voltage emergency steering system is maintained to continue running, the high-voltage electric steering system is maintained to continue shutting down, and the voltage consumption unit is turned on to reduce the real-time driving voltage.

4. The electric power steering control method according to claim 1, characterized in that: The controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operating duration of the low-voltage emergency steering system includes: When the running time is greater than the first running time, the low-voltage emergency steering system is shut down, and the magnitude relationship between the real-time driving voltage and the high-voltage undervoltage recovery threshold is determined; When the real-time driving voltage is greater than or equal to the high-voltage undervoltage recovery threshold, starting the high-voltage electric steering system; When the real-time driving voltage is less than the high-voltage undervoltage recovery threshold, the high-voltage electric steering system is kept shut down.

5. The electric power steering control method according to claim 1, characterized in that: Before controlling the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operating duration of the low-voltage emergency steering system, the method includes: When there is no steering assist requirement, the high-voltage electric steering system is kept shut down.

6. An electric steering control device, applicable to the electric steering control method according to any one of claims 1 to 5, characterized in that: include: An information acquisition module, used for acquiring the real-time driving voltage of the high-voltage electric steering system, starting the low-voltage emergency steering system, and recording the operation time of the low-voltage emergency steering system when the high-voltage electric steering system loses high voltage; A control module is used to switch and control the operating states of the high-voltage electric steering system and the low-voltage emergency steering system based on the magnitude of the real-time driving voltage and the operating time of the low-voltage emergency steering system, wherein the switching time between the high-voltage electric steering system and the low-voltage emergency steering system is greater than a preset time threshold.

7. A vehicle, characterized in that: comprising a memory and a processor, wherein: The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the electric steering control method described in any one of claims 1 to 5 above.

8. A computer-readable storage medium, characterized in that: Used to store computer-readable programs or instructions, which, when executed by a processor, can implement the steps of the electric steering control method described in any one of claims 1 to 5.

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