A method for switching the working mode of a brake-by-wire booster system

Abstract

The application relates to the technical field of brake boosters, in particular to a working mode switching method of a brake-by-wire booster system. The working modes include a power-on processing mode, a power-on detection mode, a standby mode, a boost working mode, a power-off detection mode, a power-off processing mode, a low-power-consumption mode and a hibernation mode. The switching method includes: switching the power-on processing mode to the power-on detection mode and the standby mode; switching the power-on detection mode to the standby mode; switching the standby mode to the boost working mode, the power-off detection mode or the low-power-consumption mode; switching the boost working mode to the standby mode; switching the power-off detection mode to the power-off processing mode and the standby mode; switching the power-off processing mode to the hibernation mode and the standby mode; switching the low-power-consumption mode to the standby mode and the power-off processing mode; and switching the hibernation mode to the power-on processing mode. The working modes of the existing brake-by-wire booster system cannot adapt to complex driving scenes and user behavior requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of brake boosters, in particular to a working mode switching method of a brake-by-wire booster system. BACKGROUND

[0002] In current vehicle braking systems, the switching logic of the working mode of the traditional brake-by-wire booster system is relatively simple, usually only containing a working mode and a sleep mode. However, with the development of vehicle control technology, vehicle braking control is becoming more and more sophisticated, and the working mode of the traditional brake-by-wire booster system has been unable to adapt to the needs of complex driving scenarios and user behaviors.

[0003] In view of the above situation, the present application provides a working mode switching method of a brake-by-wire booster system. The working mode of the system includes eight working modes: power-on processing mode, power-on detection mode, standby mode, boost working mode, power-off detection mode, power-off processing mode, low-power mode and sleep mode, which are respectively used to cope with different scenarios, and the switching of the working mode is performed through comprehensive judgment of various signal conditions such as EPB state and brake pedal signal. SUMMARY

[0004] To solve the problem that the working mode of the existing brake-by-wire booster system cannot adapt to the needs of complex driving scenarios and user behaviors, the present application provides a working mode switching method of a brake-by-wire booster system.

[0005] In a first aspect, the present application provides a working mode switching method of a brake-by-wire booster system, wherein the working mode of the brake-by-wire booster system includes: power-on processing mode, power-on detection mode, standby mode, boost working mode, power-off detection mode, power-off processing mode, low-power mode and sleep mode.

[0006] The power-on processing mode is used to start the driving module, and when the first switching condition is met, the power-on processing mode is switched to the power-on detection mode or the standby mode.

[0007] The power-on detection mode is used to diagnose power-on faults of the system and complete motor zero position learning when powered on, and when the second switching condition is met, the power-on detection mode is switched to the standby mode.

[0008] The standby mode is used to respond to vehicle braking requirements in real time, and when the third switching condition is met, the standby mode is switched to the boost working mode, or the power-off detection mode, or the low-power mode.

[0009] The boost working mode is used to drive the boost motor to respond to braking requirements, and when the fourth switching condition is met, the boost working mode is switched to the standby mode.

[0010] The power-off detection mode is used for power-off fault diagnosis of the system when powering off, and switches from the power-off detection mode to the power-off processing mode or the standby mode when the fifth switching condition is met;

[0011] The power-off processing mode is used for closing the driving module, and switches from the power-off processing mode to the hibernation mode or the standby mode when the sixth switching condition is met;

[0012] The low-power consumption mode is used for balancing the battery power consumption and the brake request response time, and closing the driving module, and switches from the low-power consumption mode to the standby mode or the power-off processing mode when the seventh switching condition is met;

[0013] The hibernation mode is used for the system entering the hibernation state after the vehicle powers off, and switches from the hibernation mode to the power-on processing mode when the eighth switching condition is met.

[0014] In some embodiments, the first switching condition includes a first condition and a second condition:

[0015] If the first condition is met, the system switches from the power-on processing mode to the standby mode, and the first condition is that the brake pedal is detected to be stepped on and the EPB is in the released state;

[0016] If the second condition is met, the system switches from the power-on processing mode to the power-on detection mode, and the second condition is that the brake pedal is detected to be not stepped on or the EPB is in the enabled state.

[0017] In some embodiments, the second switching condition includes a third condition and a fourth condition;

[0018] If the third condition is met, the system switches from the power-on detection mode to the standby mode, and the third condition is that the brake pedal is detected to be stepped on and the EPB is in the released state during the power-on detection process;

[0019] If the fourth condition is met, the system switches from the power-on detection mode to the standby mode, and the fourth condition is that the power-on detection is completed.

[0020] In some embodiments, the third switching condition includes a fifth condition, a sixth condition and a seventh condition;

[0021] If the fifth condition is met, the system switches from the standby mode to the assist working mode, and the fifth condition is that the vehicle has a brake demand;

[0022] If the sixth condition is met, the system switches from the standby mode to the power-off detection mode, and the sixth condition is that the ignition signal is detected to disappear, the vehicle door is detected to be closed, and the time that the main driver seat is detected to be unoccupied exceeds a first time;

[0023] If the seventh condition is met, the system switches from the standby mode to the low-power mode, the seventh condition being that the ignition signal is detected to disappear, the vehicle door is detected to be not closed, and the driver seat is detected to have a person.

[0024] In some embodiments, the fourth switching condition is that the brake pedal is detected to be not stepped on, the vehicle brake request is detected to be zeroed, the assist motor is detected to return to the initial position, and the solenoid valve is detected to return to the default state.

[0025] In some embodiments, the power-off fault diagnosis includes judging whether the drive module, the brake actuator, and the microcontroller have faults, and performing hydraulic system leakage detection.

[0026] In some embodiments, the fifth switching condition includes an eighth condition and a ninth condition.

[0027] If the eighth condition is met, the system switches from the power-off detection mode to the power-off processing mode, the eighth condition being that the power-off detection is completed.

[0028] If the ninth condition is met, the system switches from the power-off detection mode to the standby mode, the ninth condition being that the ignition signal is detected to start during the power-off detection process.

[0029] In some embodiments, the sixth switching condition includes a tenth condition and an eleventh condition.

[0030] If the tenth condition is met, the system switches from the power-off processing mode to the sleep mode, the tenth condition being that the power-off processing is detected to be completed.

[0031] If the eleventh condition is met, the system switches from the power-off processing mode to the standby mode, the eleventh condition being that the ignition signal is detected to start.

[0032] In some embodiments, the seventh switching condition includes a twelfth condition and a thirteenth condition.

[0033] If the twelfth condition is met, the system switches from the low-power mode to the standby mode, the twelfth condition being that the brake pedal is detected to be stepped on.

[0034] If the thirteenth condition is met, the system switches from the low-power mode to the power-off processing mode, the thirteenth condition being that the vehicle door is detected to be closed and no one is detected to be in the driver seat for more than a second time.

[0035] In some embodiments, the eighth switching condition is that any one of the vehicle start signal, the brake pedal stepping signal, the driver door opening signal, and the driver seat person signal is detected.

[0036] To solve the problem that the working mode of the existing brake-by-wire booster system cannot adapt to the needs of complex driving scenarios and user behavior, the present application has the following advantages:

[0037] By designing multiple working modes, the brake-by-wire booster system can be targeted at different driving scenarios and user behavior requirements, unnecessary power consumption is reduced through multi-mode hierarchical management, and cost is saved; through standby mode, it can be switched to booster working mode instantly, shortening the brake response time and improving the brake performance; through the power-off detection mode, the time-consuming hydraulic system leakage detection can be completed, and the brake risk is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 A working mode switching diagram of a brake-by-wire booster system working mode switching method is shown. DETAILED DESCRIPTION

[0039] The present disclosure will now be discussed with reference to several example embodiments. It should be appreciated that these embodiments are discussed only to better illustrate the present disclosure and thus enable its best utilization, and are not intended to limit the scope of the present disclosure in any way.

[0040] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0041] This embodiment discloses a method for switching the operating mode of a brake-by-wire booster system, such as... Figure 1 As shown, the operating modes of the brake-by-wire booster system include: power-on processing mode, power-on detection mode, standby mode, booster operation mode, power-off detection mode, power-off processing mode, low power consumption mode, and sleep mode.

[0042] The power-on processing mode is used to start the drive module. When the first switching condition is met, the power-on processing mode is switched to the power-on detection mode or the standby mode.

[0043] The power-on detection mode is used to diagnose power-on faults and complete motor zero-position learning when the system is powered on. When the second switching condition is met, the system switches from the power-on detection mode to the standby mode.

[0044] The standby mode is used to respond to the braking demand of the vehicle in real time, and switches from the standby mode to the assist working mode or the power-off detection mode or the low-power consumption mode when the third switching condition is met.

[0045] The assist working mode is used to drive the assist motor to respond to the braking demand, and switches from the assist working mode to the standby mode when the fourth switching condition is met.

[0046] The power-off detection mode is used to diagnose the power-off fault of the system when the power is off, and switches from the power-off detection mode to the power-off processing mode or the standby mode when the fifth switching condition is met.

[0047] The power-off processing mode is used to close the driving module, and switches from the power-off processing mode to the hibernation mode or the standby mode when the sixth switching condition is met.

[0048] The low-power consumption mode is used to balance the power consumption of the battery and the braking request response time, and closes the driving module, and switches from the low-power consumption mode to the standby mode or the power-off processing mode when the seventh switching condition is met.

[0049] The hibernation mode is used for the system to enter the hibernation state after the vehicle is powered off, and switches from the hibernation mode to the power-on processing mode when the eighth switching condition is met.

[0050] In the embodiment, eight working modes of the electric power brake booster system are proposed, each mode coping with different application scenarios and corresponding to switching to a specified working mode. For example, after the vehicle is started and powered on, the power-on processing mode is entered immediately to start the driving module. After the power-on processing is completed, the system switches to the power-on detection mode. If the vehicle generates a braking demand or detects that the brake pedal is stepped on and the EPB state is the parking state during the power-on processing, the standby mode is entered immediately to respond to the braking demand at any time.

[0051] Specifically, the eight working modes are the power-on processing mode, the power-on detection mode, the standby mode, the assist working mode, the power-off detection mode, the power-off processing mode, the low-power consumption mode and the hibernation mode.

[0052] Specifically, the power-on processing mode is used to start the driving module to prepare for braking, and after the power-on processing is completed, the power-on detection mode is entered, or after the power-on detection is completed, the vehicle generates a braking demand, and then the standby mode is switched to respond to the braking demand at any time.

[0053] Specifically, the power-on detection mode is used to diagnose the power-on fault of the system when the power is on, and when the self-checking is completed or the vehicle has a braking demand during the detection process, the power-on detection mode is exited and the standby mode is switched to respond to the braking demand at any time.

[0054] Specifically, the standby mode is used to respond to the braking demand of the vehicle in real time, and the standby mode is a necessary pre-mode of the power-assisted braking, that is, as long as the vehicle generates a braking demand, the standby mode will be switched to immediately, and then the standby mode is switched to the power-assisted working mode to drive the motor to respond to the braking request. The system switching to the standby mode represents that the system can already respond to the braking demand and perform braking assistance. In the standby mode, the system will be switched to any one of the power-assisted working mode, the power-off detection mode or the low-power consumption mode according to different switching conditions.

[0055] Specifically, the power-assisted working mode is used to drive the power-assisted motor to respond to the braking demand, and the power-assisted working mode can only be switched from the standby mode and will only be switched to the standby mode after meeting certain conditions.

[0056] Specifically, the power-off detection mode is used to diagnose the power-off fault of the system when the system is powered off. Unlike the real-time requirement of the power-on detection mode, the power-off detection mode can perform detection items with longer time consumption to ensure the stability of the system. The power-off detection mode will be switched to one of the power-off processing mode or the standby mode under different conditions.

[0057] Specifically, the power-off processing mode is used to close the driving module and save necessary parameters to the system, and the power-off processing mode will be switched to one of the sleep mode or the standby mode under different conditions.

[0058] Specifically, the low-power consumption mode is used to balance the power consumption of the battery and the braking request response time, and to close the driving module. The low-power consumption mode is applied to the scene where the vehicle is turned off but the door is not closed or the driver is still in the vehicle. In actual scenarios, the driver may be tired or have other things to do, such as parking and resting or handling events. At this time, the driver has no braking demand, but the vehicle has not been completely powered off and hibernated. If the system is always in a running state, the battery will be consumed. If the vehicle is completely powered off, the response time will be increased when braking is needed. The low-power consumption mode is between the two states of complete power-off hibernation and normal operation, and is used to balance the power consumption of the battery and the braking request response time. Therefore, the low-power consumption mode will be switched to one of the standby mode or the power-off processing mode under certain conditions.

[0059] Specifically, the sleep mode is used for the system to enter a sleep state after the vehicle is powered off. In the sleep mode, the system is in sleep, and only the power-related chips are still working, which can save the consumption of the battery power. When certain conditions are met, the vehicle will enter the power-on processing mode.

[0060] Specifically, by setting 8 different working modes for the line control brake booster system and setting corresponding switching conditions between different working modes, the line control brake booster system can reduce unnecessary power consumption, save costs, shorten brake response time and improve brake performance according to different driving scenarios and user behavior requirements.

[0061] In some embodiments, the first switching condition includes a first condition and a second condition:

[0062] If the first condition is met, the system switches from the power-on processing mode to the standby mode, and the first condition is that the brake pedal is detected to be stepped on and the EPB is in a released state.

[0063] If the second condition is met, the system switches from the power-on processing mode to the power-on detection mode, and the second condition is that the brake pedal is detected to be not stepped on or the EPB is in an enabled state.

[0064] In the embodiment, the first switching condition for the system to switch from the power-on processing mode to the standby mode or the power-on detection mode includes the first condition and the second condition. The first condition is that the brake pedal is detected to be stepped on and the EPB is in a released state, and the system switches to the standby mode when the first condition is met. The second condition is that the brake pedal is detected to be not stepped on or the EPB is in an enabled state, and the system switches to the power-on detection mode when the second condition is met.

[0065] Specifically, in the power-on processing mode, the hardware needs to be initialized, such as initializing IO, AD, CAN, PWM, ASIC chip, etc. After the hardware enters the normal driving state, the system needs to read the parameters, states and motor zero positions required for system operation from the non-volatile memory NVRAM, and then start the driving module. This is a necessary condition for the system to brake.

[0066] Specifically, in the case of no braking demand, i.e., the brake pedal is detected to be not stepped on or the EPB is in an enabled state, the system enters the power-on detection mode according to the set process and performs power-on detection.

[0067] Specifically, in the case of braking demand, i.e., the brake pedal is detected to be stepped on and the EPB is in a released state, the system skips the set power-on detection mode, uses the read parameters for assisted braking, switches to the standby mode, and quickly responds to the braking demand.

[0068] Specifically, by different switching logic of the power-on processing mode, when pressure needs to be built, the power-on detection mode can be skipped to quickly respond to the braking demand. When there is no braking demand, the system switches to the power-on detection mode to fully complete the power-on processing and detection, and ensures the stability of the system.

[0069] In some embodiments, the second switching condition includes a third condition and a fourth condition;

[0070] If the third condition is met, the system switches from the power-on detection mode to the standby mode, the third condition being that during the power-on detection process, it is detected that the brake pedal is stepped on and the EPB is in the released state.

[0071] If the fourth condition is met, the system switches from the power-on detection mode to the standby mode, the fourth condition being that the power-on detection is completed.

[0072] In the embodiment, the second switching condition for the system to switch from the power-on detection mode to the standby mode includes the third condition and the fourth condition. The third condition is that during the power-on detection process, it is detected that the brake pedal is stepped on and the EPB is in the released state; and the fourth condition is that the power-on detection is completed.

[0073] Specifically, the power-on detection mode will be switched to the standby mode. In the power-on mode, the power-on fault detection is performed on the system, mainly including judging whether there is a fault of the drive, the actuator and the microcontroller at present; and then the motor is reversed to learn the motor zero position.

[0074] Specifically, when the power-on detection is completed, that is, the fourth condition is met, the system completes the power-on processing and the power-on detection, and automatically switches to the standby mode to respond to the braking at any time.

[0075] Specifically, when the power-on detection process is in progress, if it is detected that there is a braking demand, that is, the third condition is met, the standby mode is immediately entered to respond to the braking demand. At the same time, the fault state and the motor zero position are determined by the values read from the non-volatile memory NVRAM in the power-on processing mode.

[0076] Specifically, in the normal self-checking process, the power-on detection mode can perform fault detection and motor zero position learning to ensure the stability of the system. When emergency braking is needed, the corresponding data is read from the non-volatile memory NVRAM to reduce the response time.

[0077] In some embodiments, the third switching condition includes a fifth condition, a sixth condition and a seventh condition.

[0078] If the fifth condition is met, the system switches from the standby mode to the power-assisted working mode, the fifth condition being that the vehicle has a braking demand.

[0079] If the sixth condition is met, the system switches from the standby mode to the power-off detection mode, the sixth condition being that it is detected that the ignition signal disappears, the vehicle door is closed and no one is in the main driver seat for more than a first time.

[0080] If the seventh condition is met, the system switches from the standby mode to the low-power consumption mode, the seventh condition being that it is detected that the ignition signal disappears, the vehicle door is not closed and there is someone in the main driver seat.

[0081] In the embodiment, the third switching condition for the system to switch from the standby mode to the power-on mode, the power-off detection mode or the low-power mode includes a fifth condition, a sixth condition and a seventh condition. The fifth condition is that the vehicle has a braking demand, i.e., the brake pedal is stepped on or an external braking request of the vehicle is detected, and the system switches to the power-on mode. The sixth condition is that the ignition signal is detected to disappear, the vehicle door is detected to be closed and the main driver seat is detected to be unoccupied for more than a first time, and the system switches to the power-off detection mode. The seventh condition is that the ignition signal is detected to disappear, the vehicle door is detected to be not closed and the main driver seat is detected to be occupied, and the system switches to the low-power mode.

[0082] Specifically, in the standby mode, the system is ready for power-on braking and detects the braking demand of the driver and the automatic driving system in real time, and enters the power-on mode when there is a braking demand.

[0083] Specifically, in the standby mode, multi-condition judgment is also performed according to the ignition signal, the vehicle door signal and the main driver seat signal, and when the sixth condition is met, i.e., the ignition signal is detected to disappear, the vehicle door is detected to be closed and the main driver seat is detected to be unoccupied for more than a first time, the system switches to the power-off detection mode to perform preparation operation for hibernation. In actual scenarios, the corresponding scenario can be that the vehicle has been parked, but the driver does not issue a certain hibernation instruction. More specifically, the first time can be selected as 3-6 minutes, and preferably 5 minutes.

[0084] Specifically, when the seventh condition is met, i.e., the ignition signal is detected to disappear, the vehicle door is detected to be not closed and the main driver seat is detected to be occupied, the corresponding scenario is that only the ignition signal is detected to be turned off, but it is not determined whether hibernation can be performed, and in order to balance the power consumption of the battery and the response time of the braking request, the system switches to the low-power mode.

[0085] Specifically, the standby mode is a pre-work mode of the power-on mode of the system, i.e., before the system performs power-on braking, the system will first enter the standby mode to respond to braking at any time, so as to reduce the braking response time.

[0086] In some embodiments, the fourth switching condition is that the brake pedal is detected to be not stepped on, the vehicle braking request is detected to be zero, the power-on motor is detected to return to the initial position, and the electromagnetic valve is detected to return to the default state.

[0087] In the embodiment, the fourth switching condition for the system to switch from the power-on mode to the standby mode is that the brake pedal is detected to be not stepped on, the vehicle braking request is detected to be zero, the power-on motor is detected to return to the initial position, and the electromagnetic valve is detected to return to the default state.

[0088] Specifically, in the power-on mode, the start output torque is clicked and the required braking pressure is established. When the conditions in the fourth switching condition are met at the same time, the corresponding scenario is that the power-on braking work has been completed, and the system switches to the standby mode to respond to the next braking at any time.

[0089] In some embodiments, the power-off fault diagnosis comprises judging whether the drive module, brake actuator, microcontroller has a fault, and performing hydraulic system leakage detection.

[0090] In the present embodiment, the difference between the power-off fault diagnosis and the power-on fault diagnosis is that the hydraulic system leakage detection can be performed.

[0091] Specifically, the hydraulic system is a key component of the brake-by-wire booster, and leakage of the hydraulic system will cause unstable pressure and unstable motor speed, thereby affecting the output (thrust or torque) of the actuator (such as a hydraulic cylinder or a hydraulic motor), changing the flow into the actuator, causing uneven motor movement speed (or speed), and failing to meet the requirements of precise control, directly affecting the stability and reliability of the equipment, and subsequently reducing system efficiency and causing vicious cycles. Therefore, it is necessary to detect the leakage of the hydraulic system. The hydraulic system leakage detection requires a relatively long execution time, so the power-on detection mode cannot be completed if there is a requirement for the inspection time, and the power-off detection mode is a system operation before the vehicle enters hibernation, which has sufficient time to complete the detection and can avoid a series of adverse effects caused by hydraulic leakage.

[0092] In some embodiments, the fifth switching condition comprises an eighth condition and a ninth condition.

[0093] If the eighth condition is met, the system switches from the power-off detection mode to the power-off processing mode, and the eighth condition is that the power-off detection is completed.

[0094] If the ninth condition is met, the system switches from the power-off detection mode to the standby mode, and the ninth condition is that the ignition signal is detected to start during the power-off detection process.

[0095] In the present embodiment, the fifth switching condition for the system to switch from the power-off detection mode to one of the power-off processing mode or the standby processing mode comprises the eighth condition and the ninth condition. The eighth condition is that the power-off detection is completed, and the system switches to the power-off processing mode. The ninth condition is that the ignition signal is detected to start during the power-off detection process, and the system switches to the standby mode.

[0096] Specifically, the power-off detection mode mainly performs power-off fault diagnosis, and both the power-off detection mode and the power-off processing mode are system operations before hibernation.

[0097] Specifically, if the ignition signal is detected to start during the power-off detection process, the corresponding scenario may be that the vehicle is restarted and a brake demand may occur at any time, so the standby mode is entered to respond to the brake at any time.

[0098] Specifically, the power-off processing mode is a necessary working mode before hibernation, and the system detects the power-off processing mode to ensure that the vehicle does not have faults and hydraulic leaks after restarting, so as to ensure the stability of the power-assisted braking.

[0099] In some embodiments, the sixth switching condition includes a tenth condition and an eleventh condition.

[0100] If the tenth condition is met, the system switches from the power-off processing mode to the hibernation mode, and the tenth condition is that the power-off processing is detected to be completed.

[0101] If the eleventh condition is met, the system switches from the power-off processing mode to the standby mode, and the eleventh condition is that the ignition signal is detected to be started.

[0102] In this embodiment, the sixth switching condition for the system to switch from the power-off processing mode to the hibernation mode or the standby mode includes the tenth condition and the eleventh condition. The tenth condition is that the power-off processing is detected to be completed, and the system switches to the hibernation mode. The eleventh condition is that the ignition signal is detected to be started, and the system switches to the standby mode.

[0103] Specifically, the power-off processing mode is a necessary working mode before hibernation, and the system will write the data required for the next power-on, such as parameters, states, motor zero positions, etc., into the NVRAM in the power-off processing mode, and will also turn off the drive module. More specifically, in order to control the number of times of writing to the NVRAM, only when the data changes, the writing is performed.

[0104] Specifically, when the system completes the power-off processing, it indicates that the system has completed the operation before hibernation, and the system will request the power chip to turn off the power supply to the microcontroller, and the microcontroller stops working and switches to the hibernation mode.

[0105] Specifically, when the power-off processing mode is running, the ignition signal is detected again, the vehicle may have a braking demand at any time, and the system switches to the standby mode to respond to the braking demand at any time.

[0106] In some embodiments, the seventh switching condition includes a twelfth condition and a thirteenth condition.

[0107] If the twelfth condition is met, the system switches from the low-power mode to the standby mode, and the twelfth condition is that the brake pedal is detected to be stepped on.

[0108] If the thirteenth condition is met, the system switches from the low-power mode to the power-off processing mode, and the thirteenth condition is that the vehicle door is detected to be closed and no one is in the main driver seat for more than a second time.

[0109] In the embodiment, the seventh switching condition for the system to switch from the low-power mode to the standby mode or the power-off processing mode includes a twelfth condition and a thirteenth condition. The twelfth condition is that the brake pedal is detected to be stepped on, and the system switches to the standby mode. The thirteenth condition is that the vehicle door is detected to be closed, and the main driver seat is detected to be unoccupied for more than a second time, and the system switches to the power-off processing mode.

[0110] Specifically, in the low-power mode, the system turns off the driving module, and the microcontroller works in a low-frequency mode. At this time, the power consumption of the system is low, and the program is in a running state, so that the braking demand can be monitored. Therefore, this mode can balance the low power consumption of the battery and the timeliness of the braking request response.

[0111] Specifically, when the vehicle door is detected to be closed, and the main driver seat is detected to be unoccupied for more than a second time (the thirteenth condition), the corresponding scenario can be that the vehicle has stopped, and the system can be hibernated, so as to enter the necessary working mode before hibernation, that is, the power-off processing mode. More specifically, the second time can be selected to be 3-6 minutes, and preferably 5 minutes.

[0112] Specifically, when the brake pedal is detected to be stepped on, the vehicle has braking demand again, and the standby mode is performed to respond to the braking demand at any time.

[0113] Specifically, through the low-power mode, the power consumption of the battery and the timeliness of the braking demand response can be effectively balanced.

[0114] In some embodiments, the eighth switching condition is any one of a vehicle start signal, a brake pedal stepping signal, a main driver door opening signal, and a main driver seat occupancy signal.

[0115] In the embodiment, after the whole vehicle is powered off, the brake-by-wire booster system judges that the system can enter hibernation. In this mode, only the chips related to the power supply work in the system circuit, and the current of the whole circuit is minimum, so as to reduce the consumption of the battery power. When any one of a vehicle start signal, a brake pedal stepping signal, a main driver door opening signal, and a main driver seat occupancy signal is detected, the power-on processing mode is re-entered.

[0116] In summary, the present application designs multiple working modes, so that the brake-by-wire booster system can be adapted to different driving scenarios and user behavior demands, and through multi-mode hierarchical management, unnecessary power consumption is reduced, and cost is saved. Through the standby mode, the booster working mode can be switched instantly, the braking response time is shortened, and the braking performance is improved. Through the power-off detection mode, the hydraulic system leakage detection with a long time consumption can be completed, and the braking risk is avoided.

[0117] It will be obvious to a person skilled in the art that the application is not limited to the details of the above-described exemplary embodiments, but that the application can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments should, therefore, be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[0118] Furthermore, it should be understood that, although the present specification describes exemplary embodiments, not every embodiment contains only one independent technical solution, and the present specification is described in this way only for the sake of clarity, and a person skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that a person skilled in the art can understand.

Claims

1. A method of switching the operation mode of a brake-by-wire booster system, characterized by, The working modes of the brake-by-wire booster system include: a power-on processing mode, a power-on detection mode, a standby mode, a boost working mode, a power-off detection mode, a power-off processing mode, a low-power consumption mode and a hibernation mode; The power-on processing mode is used to start the driving module, and when the first switching condition is met, the power-on processing mode is switched to the power-on detection mode or the standby mode; The power-on detection mode is used to diagnose power-on faults of the system when powered on, and complete motor zero position learning, and when the second switching condition is met, the power-on detection mode is switched to the standby mode; The standby mode is used to respond to vehicle braking requirements in real time, and when the third switching condition is met, the standby mode is switched to the boost working mode, or the power-off detection mode, or the low-power consumption mode; The boost working mode is used to drive the boost motor to respond to braking requirements, and when the fourth switching condition is met, the boost working mode is switched to the standby mode; The power-off detection mode is used to diagnose power-off faults of the system when powered off, and when the fifth switching condition is met, the power-off detection mode is switched to the power-off processing mode or the standby mode; The power-off processing mode is used to close the driving module, and when the sixth switching condition is met, the power-off processing mode is switched to the hibernation mode or the standby mode; The low-power consumption mode is used to balance the power consumption of the battery and the braking request response time, and to close the driving module, and when the seventh switching condition is met, the low-power consumption mode is switched to the standby mode or the power-off processing mode; The hibernation mode is used for the system to enter a hibernation state after the vehicle is powered off, and when the eighth switching condition is met, the hibernation mode is switched to the power-on processing mode; The third switching condition includes the fifth condition, the sixth condition and the seventh condition; If the fifth condition is met, the system switches from the standby mode to the boost working mode, and the fifth condition is that the vehicle has a braking requirement; If the sixth condition is met, the system switches from the standby mode to the power-off detection mode, and the sixth condition is that the ignition signal is detected to disappear, the vehicle door is detected to be closed, and the main driver seat is detected to be unoccupied for more than a first time; If the seventh condition is met, the system switches from the standby mode to the low-power consumption mode, and the seventh condition is that the ignition signal is detected to disappear, the vehicle door is detected to be not closed, and the main driver seat is detected to be occupied.

2. The method of claim 1, wherein The first switching condition includes a first condition and a second condition: If the first condition is met, the system switches from the power-on processing mode to the standby mode, and the first condition is that the brake pedal is detected to be depressed and the EPB is in a released state; If the second condition is met, the system switches from the power-on processing mode to the power-on detection mode, and the second condition is that the brake pedal is detected to be not depressed or the EPB is in an enabled state.

3. The method of claim 1, wherein The second switching condition includes a third condition and a fourth condition; If the third condition is met, the system switches from the power-on detection mode to the standby mode, and the third condition is that during the power-on detection process, the brake pedal is detected to be depressed and the EPB is in a released state; If the fourth condition is met, the system switches from the power-on detection mode to the standby mode, and the fourth condition is that the power-on detection is completed.

4. The method of claim 1, wherein The fourth switching condition is that the brake pedal is detected to be not depressed, the vehicle braking request is reset to zero, the boost motor returns to the initial position, and the electromagnetic valve returns to the default state.

5. The method of switching the operation mode of a brake-by-wire booster system according to claim 1, characterized in that, The power-off fault diagnosis includes judging whether the driving module, brake actuator, and microcontroller have faults, and detecting a hydraulic system leakage.

6. The method of switching the operation mode of a brake-by-wire booster system according to claim 5, characterized in that, The fifth switching condition includes an eighth condition and a ninth condition. If the eighth condition is met, the system switches from the power-off detection mode to the power-off processing mode, and the eighth condition is that the power-off detection is completed. If the ninth condition is met, the system switches from the power-off detection mode to the standby mode, and the ninth condition is that the ignition signal is detected to start during the power-off detection.

7. The method of switching the operation mode of a brake-by-wire booster system according to claim 1, characterized in that, The sixth switching condition includes a tenth condition and an eleventh condition. If the tenth condition is met, the system switches from the power-off processing mode to the sleep mode, and the tenth condition is that the power-off processing is detected to be completed. If the eleventh condition is met, the system switches from the power-off processing mode to the standby mode, and the eleventh condition is that the ignition signal is detected to start.

8. The method of operating mode switching of a brake-by-wire booster system according to claim 1, characterized by, The seventh switching condition includes a twelfth condition and a thirteenth condition. If the twelfth condition is met, the system switches from the low-power-consumption mode to the standby mode, and the twelfth condition is that the brake pedal is detected to be stepped on. If the thirteenth condition is met, the system switches from the low-power-consumption mode to the power-off processing mode, and the thirteenth condition is that the vehicle door is detected to be closed and no one is detected to be in the driver seat for more than a second time.

9. The method of operating mode switching of a brake-by-wire booster system according to claim 1, characterized by, The eighth switching condition is that any one of the vehicle start signal, the brake pedal stepping-on signal, the driver door opening signal, and the driver seat occupancy signal is detected.

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