Power steering system control method, control device, storage medium and vehicle

Abstract

The present invention relates to a steering assist system control method, comprising the following steps: obtaining an ignition switch state, an idle start-stop state, and an engine state; switching the steering assist control mode to a start-stop assist mode when the ignition switch state is ON and the idle start-stop state is in start-stop standby, automatic starting, automatic stopping, or automatic operation; and switching the steering assist control mode to a conventional assist mode when the ignition switch state is ON and the idle start-stop state is in automatic start-stop off or automatic start-stop is unavailable. The present invention also provides a control device. The present invention also provides a storage medium. The present invention also provides a vehicle. The present invention has the following features: steering assist can be provided during idle automatic stop; steering assist is not provided under driver-initiated vehicle shutdown conditions; and a start-stop assist control strategy is rationally configured to meet the steering assist requirement during idle automatic stop while reducing reliance on the vehicle's battery charge.

Description

Technical Field

[0001] The present invention relates to a vehicle, and in particular to a steering power system control method, a control device, a storage medium and a vehicle. Background Art

[0002] Some vehicles are equipped with an idle start-stop function, but the steering system assist logic under the idle start-stop conditions is not specifically designed. The same steering system assist logic is used when the idle start-stop function is turned on and off, resulting in the steering system not providing assist during the idle automatic shutdown period, reducing the driver's driving experience during the idle automatic shutdown period.

[0003] To enhance the driver's experience during automatic idle stop, some vehicles have incorporated specialized steering assist logic for idle start-stop operation. The steering assist controller receives an idle start-stop enable or disable signal from the CAN bus. When this signal is received, it activates assist mode and drives the power-assist motor based on vehicle speed and torque angle signals.

[0004] With the above solution, the vehicle's power steering system can provide power steering during the automatic idle shutdown period, but there are still the following three technical problems:

[0005] First, there is no distinction between driver-initiated shutdown conditions and idle automatic shutdown conditions. The steering system power-assistance logic is the same during idle automatic shutdown and driver-initiated shutdown. During driver-initiated shutdown, if the idle start-stop signal is on and the ignition switch is on, the steering system power-assistance controller will drive the power-assistance motor to provide steering assistance, increasing the steering system's consumption of the vehicle's battery power. However, the driver does not need to steer during driver-initiated shutdown.

[0006] Secondly, the steering system's power assist capability during automatic idle stop is the same as that during vehicle operation. Without a design constraint on the steering system's power assist capability during automatic idle stop, the steering system's high battery consumption could easily lead to a battery drain. Frequent engine restarts in this situation would weaken the energy-saving and environmentally friendly benefits of the idle start-stop feature.

[0007] Third, the fault state of the idle start-stop function is not differentiated. When the idle start-stop function is in a faulty state, the steering system may incorrectly provide or cut off power assistance. Summary of the Invention

[0008] An object of the present invention is to provide a steering assist system control method, a control device, a storage medium and a vehicle to alleviate or eliminate at least one of the above-mentioned technical problems.

[0009] A method for controlling a power steering system according to the present invention comprises the following steps:

[0010] Get the ignition switch status, idle start / stop status, and engine status;

[0011] When the ignition switch is in the ON state and the idle start-stop state is in the start-stop standby mode, the automatic start mode, the automatic stop mode, or the automatic operation mode, the steering power assist control mode is switched to the start-stop power assist mode;

[0012] When the ignition switch is in the ON state and the idle start-stop state is the automatic start-stop off state or the automatic start-stop is unavailable, switching the steering power-assistance control mode to the normal power-assistance mode;

[0013] In the start-stop assist mode, when the idle start-stop state is in the start-stop standby state or in the automatic start state, the assist motor is controlled to stop working; when the idle start-stop state is in the automatic stop state or in the automatic operation state, the assist motor is controlled according to the preset start-stop assist control strategy;

[0014] In the conventional power-assist mode, when the engine state is actively shut down, the power-assist motor is controlled to stop working; when the engine state is not actively shut down, the power-assist motor is controlled according to a preset conventional power-assist control strategy.

[0015] Optionally, controlling the power-assist motor according to a preset conventional power-assist control strategy includes the following steps: obtaining the vehicle speed and steering wheel torque angle, determining a first target steering assist according to the vehicle speed, steering wheel torque angle and a preset first mapping relationship, and controlling the power-assist motor to output steering assist according to the first target steering assist.

[0016] Optionally, controlling the power-assist motor according to a preset start-stop power-assist control strategy includes the following steps: when the idle start-stop state is in automatic operation, obtaining the vehicle speed and steering wheel torque angle, determining a second target steering assist according to the vehicle speed, steering wheel torque angle and a preset second mapping relationship, and controlling the power-assist motor to output steering assist according to the second target steering assist.

[0017] Optionally, controlling the power-assist motor according to a preset start-stop power-assist control strategy includes the following steps: when the idle start-stop state is in automatic shutdown, obtaining the vehicle speed and steering wheel torque angle, and determining a third target steering assist according to the vehicle speed, steering wheel torque angle and a preset third mapping relationship; when the third target steering assist is not greater than the preset maximum steering assist, controlling the power-assist motor to output steering assist according to the third target steering assist; when the third target steering assist is greater than the preset maximum steering assist, controlling the power-assist motor to output steering assist according to the maximum steering assist.

[0018] Optionally, the second mapping relationship is the same as the third mapping relationship.

[0019] Optionally, in the start-stop power-assist mode, when a fault is detected, the steering power-assist control mode is switched to the normal power-assist mode.

[0020] Optionally, when the ignition switch is in OFF state, the power assist motor is controlled to stop working.

[0021] The present invention also provides a control device, comprising:

[0022] Data acquisition module, used to obtain ignition switch status, idle start-stop status and engine status;

[0023] a mode switching module, configured to switch the steering power assist control mode to the start-stop assist mode when the ignition switch is in the ON state and the idle start-stop state is in the start-stop standby state, the automatic start state, the automatic stop state, or the automatic operation state, and to switch the steering power assist control mode to the normal assist mode when the ignition switch is in the ON state and the idle start-stop state is in the automatic start-stop off state or the automatic start-stop is unavailable;

[0024] a conventional power-assistance module, configured to, in the conventional power-assistance mode, stop controlling the power-assistance motor when the engine is in an active shutdown state, and control the power-assistance motor according to a preset conventional power-assistance control strategy when the engine is not in an active shutdown state;

[0025] The start-stop assist module is used to stop controlling the assist motor in the start-stop assist mode when the idle start-stop state is in start-stop standby or automatic start, and to control the assist motor according to a preset start-stop assist control strategy when the idle start-stop state is in automatic stop or automatic operation.

[0026] The present invention further proposes a storage medium, in which a computer program is stored. When the computer program is executed by one or more processors, any of the above-mentioned power steering system control methods is implemented.

[0027] The present invention also provides a vehicle comprising the above-mentioned control device.

[0028] The present invention has the following features: steering assistance can be provided during automatic idle shutdown, thereby improving the driver's driving experience; when the driver actively shuts down the vehicle, no steering assistance is provided, which can reduce the consumption of vehicle battery power; a reasonable setting of the start-stop assistance control strategy can reduce the dependence on vehicle battery power while meeting the steering assistance demand during automatic idle shutdown, which helps to reduce the risk of vehicle battery depletion; when the automatic start-stop function is unavailable, the steering assistance control mode is switched to the normal assistance mode, which can prevent the erroneous provision of steering assistance or the erroneous cutting off of steering assistance, thereby helping to improve the driver's safe driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow chart of the steering assist system control method described in a specific embodiment;

[0030] Figure 2 It is a structural diagram of the control device described in the specific embodiment;

[0031] Figure 3 It is a structural schematic diagram of the power steering system described in the specific implementation manner. DETAILED DESCRIPTION

[0032] The following describes the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the various details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are intended only to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0033] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0034] like Figure 1 A steering power system control method shown includes the following steps:

[0035] S10: Acquire ignition switch status, idle start / stop status, and engine status;

[0036] S20: When the ignition switch is in the ON state and the idle start-stop state is in the start-stop standby mode, the automatic start mode, the automatic stop mode, or the automatic operation mode, switching the steering assist control mode to the start-stop assist mode;

[0037] S30: When the ignition switch is in the ON state and the idle start-stop state is the automatic start-stop off state or the automatic start-stop is unavailable, switching the steering power-assistance control mode to the normal power-assistance mode;

[0038] S40: In the start-stop assist mode, when the idle start-stop state is in the start-stop standby state or in the automatic start state, controlling the assist motor to stop operation; when the idle start-stop state is in the automatic stop state or in the automatic operation state, controlling the assist motor according to a preset start-stop assist control strategy;

[0039] S50: In the conventional power-assist mode, when the engine state is actively shut down, the power-assist motor is controlled to stop working; when the engine state is not actively shut down, the power-assist motor is controlled according to a preset conventional power-assist control strategy.

[0040] In specific implementation, the above-mentioned steering power system control method can be applied to the steering power system of a vehicle. Figure 3 As shown, the power steering system includes an engine electronic control unit (ECU) 2, a vehicle speed sensor 3, a steering wheel torque sensor 4, an ignition switch 5, a power steering controller 1, a power assist motor 7, and a power supply 6. The ECU 2 generates two signals, one indicating engine status and the other indicating idle start / stop status. The vehicle speed sensor 3 generates a vehicle speed signal, and the steering wheel torque sensor 4 generates a steering wheel torque angle signal. These signals are received by the power steering controller 1 via the CAN bus. The ignition switch 5 generates an ignition switch voltage signal, which the power steering controller 1 receives to determine the ignition switch status. The power steering controller 1 outputs a current to drive the power assist motor 7 to provide steering assistance. The power steering controller 1 controls the output current to control the amount of steering assistance provided by the power assist motor 7. The power supply 6, which can be a battery or a generator, provides the required power to the power steering controller 1. The power steering controller 1 includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, implements the aforementioned power steering system control method.

[0041] By adopting the above-mentioned steering power-assist system control method, steering power can be provided during the idle automatic shutdown period, thereby improving the driver's driving experience; when the driver actively stops the vehicle, no steering power is provided, which can reduce the consumption of vehicle battery power; when the automatic start-stop function is unavailable, the steering power-assist control mode is switched to the normal power-assist mode, which can prevent the incorrect provision of steering power or the incorrect cutting off of steering power, thereby helping to improve the driver's safe driving experience; when the idle start-stop state is in start-stop standby or automatic start, the power-assist motor is controlled to stop working, which can reduce the consumption of vehicle battery power during start-stop standby and ensure that the engine can start smoothly during automatic start.

[0042] In some embodiments, controlling the power-assist motor according to a preset conventional power-assist control strategy includes the following steps: obtaining vehicle speed and steering wheel torque angle, determining a first target steering assist according to the vehicle speed, steering wheel torque angle, and a preset first mapping relationship, and controlling the power-assist motor to output steering assist according to the first target steering assist. In a specific implementation, the vehicle speed sensor sends a vehicle speed signal and the steering wheel torque sensor sends a steering wheel torque angle signal, which are received by the power-assist steering controller via the CAN bus. The memory of the power-assist steering controller stores a first mapping relationship between the vehicle speed, steering wheel torque angle, and the first target steering assist, thereby determining the first target steering assist. The power-assist steering controller controls the magnitude of the output current according to the first target steering assist, and then controls the power-assist motor to output steering assist corresponding to the first target steering assist. The first mapping relationship can be set according to the design requirements of the vehicle.

[0043] In some embodiments, controlling the power assist motor according to a preset start-stop assist control strategy includes the following steps: when the idle start-stop state is in automatic operation, obtaining the vehicle speed and steering wheel torque angle, determining a second target steering assist according to the vehicle speed, steering wheel torque angle, and a preset second mapping relationship, and controlling the power assist motor to output steering assist according to the second target steering assist. In a specific implementation, the vehicle speed signal emitted by the vehicle speed sensor and the steering wheel torque angle signal emitted by the steering wheel torque sensor are received by the power assist steering controller via the CAN bus. The memory of the power assist steering controller stores a second mapping relationship between the vehicle speed, steering wheel torque angle, and the second target steering assist, thereby determining the second target steering assist. The power assist steering controller controls the magnitude of the output current according to the second target steering assist, thereby controlling the power assist motor to output steering assist corresponding to the second target steering assist.

[0044] In some embodiments, controlling the power assist motor according to a preset start-stop assist control strategy includes the following steps: when the idle start-stop state is in automatic shutdown, obtaining the vehicle speed and steering wheel torque angle, and determining a third target steering assist force based on the vehicle speed, steering wheel torque angle, and a preset third mapping relationship; when the third target steering assist force is not greater than a preset maximum steering assist force, controlling the power assist motor to output steering assist force based on the third target steering assist force; and when the third target steering assist force is greater than a preset maximum steering assist force, controlling the power assist motor to output steering assist force based on the maximum steering assist force. In a specific implementation, a vehicle speed signal from a vehicle speed sensor and a steering wheel torque angle signal from a steering wheel torque sensor are received by a power assist steering controller via a CAN bus. A third mapping relationship between the vehicle speed, steering wheel torque angle, and the third target steering assist force is stored in a memory of the power assist steering controller, thereby determining the third target steering assist force. The power assist steering controller compares the third target steering assist force with the maximum steering assist force, and when the third target steering assist force is greater than the maximum steering assist force, controls the power assist motor to output steering assist force based on the maximum steering assist force. In specific implementation, the maximum steering assist is a calibrable value. During the vehicle development process, it can be calibrated as needed based on actual vehicle evaluation and the battery charge level. Using the above technical solution, the maximum steering assist can be calibrated to match actual needs. On the one hand, it can meet the steering assist needs during the automatic idle shutdown period, and on the other hand, it can reduce the dependence on the vehicle battery charge level, helping to reduce the risk of vehicle battery depletion. The automatic start-stop system can also monitor the battery voltage status. If it falls below the design limit, the engine electronic control unit automatically starts the engine and sends a status signal that automatic start-stop is unavailable. The steering assist controller switches the steering assist control mode to conventional assist mode. This can strike a balance between the maximum steering assist value and the battery capacity selection, achieving the maximum driving experience at a lower cost.

[0045] In some embodiments, the second mapping relationship is the same as the third mapping relationship. Further, the first mapping relationship and the second mapping relationship are the same. Using the same mapping relationship is conducive to ensuring the same steering feel and the driving experience of the driver.

[0046] In some embodiments, in the start-stop power-assist mode, when the power-steering controller detects a fault, the power-steering control mode is switched to the normal power-assist mode. The above technical solution helps ensure the reliability of the power-steering system.

[0047] In some embodiments, when the ignition switch is in the OFF state, the power assist motor is controlled to stop working. The above technical solution can reduce the consumption of the vehicle battery.

[0048] In this application, the engine status includes three states: stopped, running, and starting. Combining the operating instructions input by the driver with the engine status, it can be determined whether the engine status is actively stopped. The idle start-stop status includes six states: automatic start-stop off, start-stop standby, automatic stop, automatic start, automatic operation, and automatic start-stop unavailable. Among them, automatic start-stop off means that the idle start-stop function is not turned on and is in the off state, start-stop standby means that the engine has not started and the idle start-stop condition is met to turn on the idle start-stop function, automatic stop means that the idle start-stop function is turned on and the engine is in the stopped state, automatic starting means that the idle start-stop function is turned on and the engine is in the process of starting from stop, automatic operation means that the idle start-stop function is turned on and the engine is in the running state, and automatic start-stop unavailable means that the idle start-stop function activation condition has not been met and the idle start-stop function is unavailable. The well-known ignition switch includes four states: LOCK, ACC, ON, and START. In this application, the ignition switch voltage signal is divided into two states, ON and OFF, after being determined by the power steering controller. The well-known ignition switch LOCK, ACC, and START are all determined to be OFF states.

[0049] The present invention also proposes a control device 100, such as Figure 2 As shown, the control device 100 includes: a data acquisition module 200 for acquiring the ignition switch state, the idle start-stop state and the engine state; a mode switching module 400 for switching the steering power assist control mode to the start-stop assist mode when the ignition switch state is ON and the idle start-stop state is in the start-stop standby mode, the automatic start mode, the automatic stop mode or the automatic operation mode; and switching the steering power assist control mode to the normal assist mode when the ignition switch state is ON and the idle start-stop state is in the automatic start-stop off mode or the automatic start-stop is unavailable mode. The regular assist module 300 is used to stop controlling the assist motor in the regular assist mode when the engine state is actively shut down, and to control the assist motor according to a preset regular assist control strategy when the engine state is not actively shut down; the start-stop assist module 500 is used to stop controlling the assist motor in the start-stop assist mode when the idle start-stop state is in start-stop standby or automatic starting, and to control the assist motor according to a preset start-stop assist control strategy when the idle start-stop state is in automatic shutdown or automatic operation.

[0050] The present invention further proposes a storage medium, in which a computer program is stored. When the computer program is executed by one or more processors, any of the above-mentioned power steering system control methods is implemented.

[0051] The present invention also provides a vehicle comprising the above-mentioned control device.

[0052] The above embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the scope of protection of the present invention. In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. mean that the specific features, structures, materials or characteristics of the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

Claims

1. A method for controlling a power steering system, characterized in that: The following steps are involved: Get the ignition switch status, idle start-stop status and engine status; the idle start-stop status includes six states: automatic start-stop off, start-stop standby, automatic stop, automatic start, automatic operation, and automatic start-stop unavailable. Among them, automatic start-stop off means that the idle start-stop function is not turned on and is in the off state; start-stop standby means that the engine has not started and the idle start-stop condition is met to turn on the idle start-stop function; automatic stop means that the idle start-stop function is turned on and the engine is in the stop state; automatic start means that the idle start-stop function is turned on and the engine is in the process of starting from stop; automatic operation means that the idle start-stop function is turned on and the engine is in the running state; automatic start-stop unavailable means that the idle start-stop function activation condition is not met and the idle start-stop function is unavailable; When the ignition switch is in the ON state and the idle start-stop state is in the start-stop standby mode, the automatic start mode, the automatic stop mode, or the automatic operation mode, the steering power assist control mode is switched to the start-stop power assist mode; When the ignition switch is in the ON state and the idle start-stop state is the automatic start-stop off state or the automatic start-stop is unavailable, switching the steering power-assistance control mode to the normal power-assistance mode; In the start-stop assist mode, when the idle start-stop state is in the start-stop standby state or in the automatic start state, the assist motor is controlled to stop working; when the idle start-stop state is in the automatic stop state or in the automatic operation state, the assist motor is controlled according to the preset start-stop assist control strategy; In the conventional power-assist mode, when the engine state is actively shut down, the power-assist motor is controlled to stop working; when the engine state is not actively shut down, the power-assist motor is controlled according to a preset conventional power-assist control strategy.

2. The steering assist system control method according to claim 1, characterized in that: The controlling of the power-assist motor according to the preset conventional power-assist control strategy includes the following steps: obtaining the vehicle speed and the steering wheel torque angle, determining a first target steering assist according to the vehicle speed, the steering wheel torque angle and a preset first mapping relationship, and controlling the power-assist motor to output steering assist according to the first target steering assist.

3. The steering assist system control method according to claim 1, characterized in that: The controlling of the power-assist motor according to the preset start-stop power-assist control strategy includes the following steps: when the idle start-stop state is in automatic operation, obtaining the vehicle speed and steering wheel torque angle, determining a second target steering assist according to the vehicle speed, steering wheel torque angle and a preset second mapping relationship, and controlling the power-assist motor to output steering assist according to the second target steering assist.

4. The steering assist system control method according to claim 3, characterized in that: The controlling of the power-assist motor according to the preset start-stop power-assist control strategy includes the following steps: when the idle start-stop state is in automatic shutdown, obtaining the vehicle speed and steering wheel torque angle, and determining a third target steering assist according to the vehicle speed, steering wheel torque angle and a preset third mapping relationship; when the third target steering assist is not greater than the preset maximum steering assist, controlling the power-assist motor to output steering assist according to the third target steering assist; when the third target steering assist is greater than the preset maximum steering assist, controlling the power-assist motor to output steering assist according to the maximum steering assist.

5. The steering assist system control method according to claim 4, characterized in that: The second mapping relationship is the same as the third mapping relationship.

6. The steering assist system control method according to claim 1, characterized in that: In the start-stop power-assist mode, when a fault is detected, the steering power-assist control mode is switched to the normal power-assist mode.

7. The steering assist system control method according to claim 1, characterized in that: When the ignition switch is in the OFF state, the power assist motor is controlled to stop working.

8. A control device, characterized in that: include: A data acquisition module is used to obtain the ignition switch status, idle start-stop status and engine status; the idle start-stop status includes six states: automatic start-stop off, start-stop standby, automatic stop, automatic start, automatic operation, and automatic start-stop unavailable. Among them, automatic start-stop off means that the idle start-stop function is not turned on and is in the off state; start-stop standby means that the engine has not started and the idle start-stop condition is met to turn on the idle start-stop function; automatic stop means that the idle start-stop function is turned on and the engine is in the stop state; automatic starting means that the idle start-stop function is turned on and the engine is in the process of starting from stop; automatic operation means that the idle start-stop function is turned on and the engine is in the running state; automatic start-stop unavailable means that the idle start-stop function activation condition is not met and the idle start-stop function is unavailable; a mode switching module, configured to switch the steering power assist control mode to the start-stop assist mode when the ignition switch is in the ON state and the idle start-stop state is in the start-stop standby state, the automatic start state, the automatic stop state, or the automatic operation state, and to switch the steering power assist control mode to the normal assist mode when the ignition switch is in the ON state and the idle start-stop state is in the automatic start-stop off state or the automatic start-stop is unavailable; a conventional power-assistance module, configured to, in the conventional power-assistance mode, stop controlling the power-assistance motor when the engine is in an active shutdown state, and control the power-assistance motor according to a preset conventional power-assistance control strategy when the engine is not in an active shutdown state; The start-stop assist module is used to stop controlling the assist motor in the start-stop assist mode when the idle start-stop state is in start-stop standby or automatic start, and to control the assist motor according to a preset start-stop assist control strategy when the idle start-stop state is in automatic stop or automatic operation.

9. A storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by one or more processors, the steering assist system control method according to any one of claims 1 to 7 is implemented.

10. A vehicle, characterized in that: The invention comprises the control device described in claim 8.

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