Retarder failure control method and apparatus

Abstract

The application relates to the technical field of vehicles and discloses a retarding device fault control method and device. The method comprises the following steps: when an oil pressure sensor has a working fault, acquiring vehicle state parameters and a braking torque duty cycle table; determining a duty cycle basic value in the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table; determining an optimal duty cycle according to the duty cycle basic value and the vehicle state parameters; and controlling the retarding device to continue working based on the optimal duty cycle. The application can at least solve the problem that, due to the oil pressure sensor fault, the retarding device control of the braking torque is abnormal, is beneficial to optimizing the control process of the retarding device after the oil pressure sensor fault, and guarantees the vehicle safety of the user.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and in particular to a method and apparatus for controlling retarder malfunctions. Background Technology

[0002] Currently, hydraulic retarders that integrate the transmission and retarder regulate oil pressure by directly controlling the oil volume through solenoid valves, thereby achieving precise control of braking torque. Their control stability highly depends on real-time feedback from the oil pressure sensor. In high-intensity braking scenarios such as long downhill slopes and complex road conditions in commercial vehicles, the oil pressure sensor is susceptible to vibration, oil contamination, and circuit faults, leading to signal distortion, open circuits, or short circuits, causing the original oil pressure closed-loop control to collapse.

[0003] When a sensor fails, the solenoid valve loses its oil pressure feedback signal, the closed-loop feedback function fails, which can easily lead to abnormal oil flow and the failure of the original control process, potentially causing safety hazards such as sudden increase in braking torque, tire lock-up, or brake failure. Existing solutions often employ current-pressure mapping, multi-sensor fusion, and dual-valve redundancy, which suffer from complex algorithms and high hardware costs, and may still pose a risk of sudden changes in braking force under extreme conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a retarder fault control method and device to at least solve the problem of abnormal control of braking torque by the retarder caused by the failure of the oil pressure sensor, and to optimize the control process of the retarder after the oil pressure sensor fails, so as to ensure the safety of users' vehicles.

[0005] To address the aforementioned technical problems, in a first aspect, the present invention provides a retarder fault control method, comprising at least:

[0006] S1. When the oil pressure sensor malfunctions, acquire vehicle status parameters and braking torque duty cycle table.

[0007] S2. Determine the basic value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table;

[0008] S3. Determine the optimal duty cycle based on the duty cycle baseline value and the vehicle state parameters;

[0009] S4. Based on the optimal duty cycle, the retarder continues to operate.

[0010] Optionally, the vehicle status parameters include at least the retarder gear position, current vehicle speed, brake pedal status, retarder oil temperature, and coolant temperature.

[0011] Before step S1, the following is also included:

[0012] S11. Obtain the operating status of the oil pressure sensor, so as to determine whether the oil pressure sensor has a malfunction based at least on the operating status.

[0013] Optionally, step S2 specifically includes:

[0014] S21. Obtain the first duty cycle under the current retarder gear based on the braking torque duty cycle table;

[0015] S22. Determine the second duty cycle based on the current vehicle speed and the first duty cycle;

[0016] S23. Determine whether the brake pedal is in a depressed state;

[0017] S24. If the brake pedal is in the depressed state, the second duty cycle is multiplied by the third proportional coefficient to determine the base value of the duty cycle.

[0018] Optionally, after step S23, the method further includes:

[0019] S25. If the brake pedal is in an unpressed state, the retarder is controlled to continue working based on the second duty cycle.

[0020] Optionally, step S22 specifically includes:

[0021] S221. Determine whether the current vehicle speed is less than the first vehicle speed threshold.

[0022] S222. If the current vehicle speed is less than the first vehicle speed threshold, then the first duty cycle is determined as the second duty cycle.

[0023] S223. If the current vehicle speed is not less than the first vehicle speed threshold, then continue to determine whether the current vehicle speed is less than the second vehicle speed threshold.

[0024] S224. If the current vehicle speed is less than the second vehicle speed threshold, the first duty cycle is multiplied by the first proportional coefficient to determine the second duty cycle.

[0025] S225. If the current vehicle speed is not less than the second vehicle speed threshold, then the first duty cycle is multiplied by the second proportional coefficient to determine the second duty cycle;

[0026] Wherein, the second vehicle speed threshold is greater than the first vehicle speed threshold.

[0027] Optionally, step S3 specifically includes:

[0028] S31. Determine the third duty cycle based on the retarder oil temperature and the aforementioned duty cycle baseline value;

[0029] S32. Determine whether the temperature of the coolant is greater than a preset temperature threshold.

[0030] S33. If the coolant temperature is greater than the preset temperature threshold, the third duty cycle is multiplied by the third proportional coefficient to determine the optimal duty cycle.

[0031] Optionally, after step S32, the method further includes:

[0032] S34. If the coolant temperature is not greater than the preset temperature threshold, the retarder is controlled to continue working based on the third duty cycle.

[0033] Optionally, step S31 specifically includes:

[0034] S311. Determine whether the retarder oil temperature is lower than the first preset oil temperature;

[0035] S312. If the retarder oil temperature is lower than the first preset oil temperature, the duty cycle base value is lowered by the first preset range to obtain a third duty cycle.

[0036] S313. If the retarder oil temperature is not lower than the first preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the second preset oil temperature.

[0037] S314. If the retarder oil temperature is lower than the second preset oil temperature, then the duty cycle base value is determined as the third duty cycle.

[0038] S315. If the retarder oil temperature is not lower than the second preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the third preset oil temperature.

[0039] S316. If the retarder oil temperature is lower than the third preset oil temperature, the duty cycle base value is adjusted down by a second preset range to obtain the third duty cycle.

[0040] S317. If the retarder oil temperature is not less than the third preset oil temperature, then the preset ratio of the duty cycle base value is determined as the third duty cycle.

[0041] The third preset oil temperature is greater than the second preset oil temperature, which is greater than the first preset oil temperature.

[0042] Optionally, after step S4, the method further includes:

[0043] S5. Determine the percentage of vehicle braking torque based on the optimal duty cycle;

[0044] S6. The on-board display unit is used to display the working fault and the percentage of the vehicle's braking torque in real time.

[0045] Secondly, the present invention also provides a retarder fault control device, comprising at least:

[0046] The acquisition module is used to acquire vehicle status parameters and braking torque duty cycle table when the oil pressure sensor malfunctions.

[0047] The first determining module is used to determine the basic value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table;

[0048] The second determining module is used to determine the optimal duty cycle based on the duty cycle base value and the vehicle state parameters;

[0049] The operation control module is used to control the retarder to continue working based on the optimal duty cycle.

[0050] The technical solution provided by this invention firstly acquires vehicle status parameters and a braking torque duty cycle table when the oil pressure sensor malfunctions; secondly, it determines the basic duty cycle value under the current vehicle status based on the vehicle status parameters and the braking torque duty cycle table; then, it determines the optimal duty cycle based on the basic duty cycle value and the vehicle status parameters; finally, it controls the retarder to continue working based on the optimal duty cycle.

[0051] Therefore, this invention, on the one hand, determines the optimal duty cycle for the current vehicle state based on vehicle state parameters and a braking torque duty cycle table. It can determine the initial optimal duty cycle according to different vehicle states, and then control vehicle braking based on the optimal duty cycle, effectively avoiding braking failure or sudden torque changes, thus significantly improving driving safety. On the other hand, the control logic proposed in this invention requires no complex modeling operations, has strong anti-interference capabilities, wide adaptability, and can be implemented without adding new physical hardware, making it easy to mass-produce and deploy. Attached Figure Description

[0052] Figure 1 This is a flowchart of a retarder fault control method provided by the present invention;

[0053] Figure 2 This is a flowchart of another retarder fault control method provided by the present invention;

[0054] Figure 3 This is a schematic diagram of the structure of a retarder fault control device provided by the present invention. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0056] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0057] It should be understood that although the terms first, second, third, etc., may be used in the embodiments of the present invention, these descriptions should not be limited to these terms. These terms are only used to distinguish the descriptions. For example, first may also be referred to as second without departing from the scope of the embodiments of the present invention, and similarly, second may also be referred to as first.

[0058] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0059] Figure 1 This is a flowchart of a retarder fault control method provided by the present invention. The present invention is at least applicable to retarder control scenarios after oil pressure sensor failure. This retarder fault control method can be, but is not limited to, executed by the retarder fault control device of the present invention as the execution subject, which can be implemented in software and / or hardware. Figure 1 As shown, the retarder fault control method includes at least the following steps:

[0060] S1. When the oil pressure sensor malfunctions, acquire vehicle status parameters and braking torque duty cycle table.

[0061] The braking torque duty cycle table can be a basic PWM table of output braking torque based on gear and vehicle speed stored in the vehicle controller. It is used to obtain the rated Pulse Width Modulation (PWM) duty cycle (i.e., the first duty cycle) for the current retarder gear. The braking torque duty cycle table can be obtained through pre-experimentation. It is understood that PWM controls the average voltage or energy of the output signal by changing the proportion of the high-level time of the pulse to the entire cycle (duty cycle), thereby achieving equivalent control of the analog signal. It is also understood that when the oil pressure sensor malfunctions, the retarder's original oil pressure closed-loop control will be discontinued.

[0062] In one specific implementation, optionally, the vehicle status parameters include at least the retarder gear position, current vehicle speed, brake pedal status, retarder oil temperature, and coolant temperature. The brake pedal status includes both depressed and undepressed states. The retarder gear position indicates the retarder braking gear.

[0063] S2. Determine the base value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table.

[0064] The duty cycle base value is used to ensure smooth braking of the vehicle.

[0065] S3. Determine the optimal duty cycle based on the duty cycle baseline value and vehicle status parameters.

[0066] The optimal duty cycle is used to indirectly stabilize the braking torque based on thermal equilibrium.

[0067] S4. The retarder continues to operate based on the optimal duty cycle control.

[0068] The retarder can be an integrated hydraulic retarder. Continued operation can be achieved by outputting braking torque according to the optimal duty cycle.

[0069] The technical solution provided by this invention firstly acquires vehicle status parameters and a braking torque duty cycle table when the oil pressure sensor malfunctions; secondly, it determines the basic duty cycle value under the current vehicle status based on the vehicle status parameters and the braking torque duty cycle table; then, it determines the optimal duty cycle based on the basic duty cycle value and the vehicle status parameters; finally, it controls the retarder to continue working based on the optimal duty cycle.

[0070] Therefore, this invention, on the one hand, determines the optimal duty cycle for the current vehicle state based on vehicle state parameters and a braking torque duty cycle table. It can determine the initial optimal duty cycle according to different vehicle states, and then control vehicle braking based on the optimal duty cycle, effectively avoiding braking failure or sudden torque changes, thus significantly improving driving safety. On the other hand, the control logic proposed in this invention requires no complex modeling operations, has strong anti-interference capabilities, wide adaptability, and can be implemented without adding new physical hardware, making it easy to mass-produce and deploy.

[0071] Based on the above embodiments or implementation methods Figure 2 This is a flowchart of another retarder fault control method provided by the present invention, which is based on the above embodiments and includes additions and refinements. Figure 2 As shown, the retarder fault control method includes at least the following steps:

[0072] S11. Obtain the operating status of the oil pressure sensor to determine whether the oil pressure sensor has a malfunction, at least based on the operating status.

[0073] The operating status can include the signal output status, power supply status, and communication status of the oil pressure sensor. Operating faults can include open circuits, short circuits, or value jumps in the oil pressure sensor. It is understood that if no operating fault exists, the control logic will maintain the normal operation of the retarder.

[0074] S1. When the oil pressure sensor malfunctions, acquire vehicle status parameters and braking torque duty cycle table.

[0075] S21. Obtain the first duty cycle under the current retarder gear based on the braking torque duty cycle table.

[0076] Different retarder gears correspond to different first duty cycles. It can be understood that this invention can calibrate 5 retarder braking gears, with different retarder gears corresponding to different braking torques. Each gear does not perform pressure closed-loop control, but the calibration control valve has a fixed safety PWM duty cycle (i.e., the first duty cycle) for each retarder gear, and the calibration data is stored inside the retarder control unit.

[0077] S22. Determine the second duty cycle based on the current vehicle speed and the first duty cycle.

[0078] In another specific implementation, step S22 may optionally include:

[0079] S221. Determine whether the current vehicle speed is less than the first vehicle speed threshold.

[0080] The first vehicle speed threshold can be 30 km / h.

[0081] S222. If the current vehicle speed is less than the first vehicle speed threshold, then the first duty cycle is determined as the second duty cycle.

[0082] S223. If the current vehicle speed is not less than the first vehicle speed threshold, then continue to determine whether the current vehicle speed is less than the second vehicle speed threshold.

[0083] The second speed threshold is greater than the first speed threshold. The second speed threshold can be 60 km / h.

[0084] S224. If the current vehicle speed is less than the second vehicle speed threshold, the first duty cycle is multiplied by the first proportional coefficient to determine the second duty cycle.

[0085] The first proportionality coefficient can be 0.8.

[0086] S225. If the current vehicle speed is not less than the second vehicle speed threshold, the first duty cycle is multiplied by the second proportional coefficient to determine the second duty cycle.

[0087] The first proportionality coefficient can be 0.6.

[0088] S23. Determine whether the brake pedal is in the depressed state.

[0089] In another specific implementation, after step S23, the method further includes:

[0090] S25. If the brake pedal is not depressed, the retarder continues to operate based on the second duty cycle.

[0091] S24. If the brake pedal is in the depressed state, multiply the second duty cycle by the third proportional coefficient to determine the base value of the duty cycle.

[0092] The third proportionality coefficient can be 0.5.

[0093] S31. Determine the third duty cycle based on the retarder oil temperature and the basic duty cycle value.

[0094] In another specific implementation, step S31 specifically includes:

[0095] S311. Determine whether the retarder oil temperature is lower than the first preset oil temperature.

[0096] The first preset oil temperature can be 60°C.

[0097] S312. If the retarder oil temperature is lower than the first preset oil temperature, the duty cycle base value is adjusted down by the first preset range to obtain the third duty cycle.

[0098] The first preset range can be 10% to 15%. It is understood that the purpose of lowering the first preset range is to prevent the retarder from over-braking.

[0099] S313. If the retarder oil temperature is not lower than the first preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the second preset oil temperature.

[0100] The second preset oil temperature is higher than the first preset oil temperature. The second preset oil temperature can be 100°C.

[0101] S314. If the retarder oil temperature is lower than the second preset oil temperature, the duty cycle base value shall be determined as the third duty cycle.

[0102] S315. If the retarder oil temperature is not lower than the second preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the third preset oil temperature.

[0103] The third preset oil temperature is higher than the second preset oil temperature. The third preset oil temperature can be 140°C.

[0104] S316. If the retarder oil temperature is lower than the third preset oil temperature, the duty cycle base value will be adjusted down to the second preset range to obtain the third duty cycle.

[0105] The second preset range can be 20% to 40%. It is understood that the purpose of lowering the second preset range is to prevent the retarder from over-braking.

[0106] S317. If the retarder oil temperature is not less than the third preset oil temperature, then the basic value of the duty cycle of the preset ratio shall be determined as the third duty cycle.

[0107] The preset ratio can be 15%.

[0108] S32. Determine whether the coolant temperature is greater than the preset temperature threshold.

[0109] The preset temperature threshold can be obtained through calibration. It is understandable that when the coolant temperature exceeds the preset temperature threshold, the retarder is in an overheated state. In this case, the retarder's operation needs to be limited to prevent damage to the hardware due to high temperatures.

[0110] In another specific implementation, after step S32, the method further includes:

[0111] S34. If the coolant temperature is not greater than the preset temperature threshold, the retarder will continue to work based on the third duty cycle control.

[0112] S33. If the coolant temperature is greater than the preset temperature threshold, the third duty cycle is multiplied by the third proportional coefficient to determine the optimal duty cycle.

[0113] S4. The retarder continues to operate based on the optimal duty cycle control.

[0114] One way to control the retarder to continue working is to output the optimal duty cycle to the solenoid valve to control the retarder's operation.

[0115] S5. Determine the percentage of vehicle braking torque based on the optimal duty cycle.

[0116] It is understandable that the percentage of vehicle braking torque can be determined based on the mapping relationship between the vehicle's built-in duty cycle and the percentage of vehicle braking torque.

[0117] S6. The vehicle-mounted display unit displays working faults and the percentage of vehicle braking torque in real time.

[0118] The in-vehicle display unit can be the vehicle's central control instrument panel.

[0119] The technical solution provided by this invention is as follows: First, the operating status of the oil pressure sensor is acquired to determine whether the oil pressure sensor is malfunctioning. Further, when the oil pressure sensor is malfunctioning, vehicle status parameters and a braking torque duty cycle table are acquired. Further, a first duty cycle for the current retarder gear is acquired based on the braking torque duty cycle table. Further, a second duty cycle is determined based on the current vehicle speed and the first duty cycle. Further, it is determined whether the brake pedal is depressed. Further, if the brake pedal is not depressed, the retarder continues to operate based on the second duty cycle. Further, if the brake pedal is depressed, the second duty cycle is multiplied by a third proportional coefficient to determine a base duty cycle value. Further, a third duty cycle is determined based on the retarder oil temperature and the base duty cycle value. Further, it is determined whether the coolant temperature is greater than a preset temperature threshold. Further, if the coolant temperature is not greater than the preset temperature threshold, the retarder continues to operate based on the third duty cycle. Furthermore, if the coolant temperature exceeds a preset temperature threshold, the third duty cycle is multiplied by a third proportional coefficient to determine the optimal duty cycle. Further, the retarder continues to operate based on the optimal duty cycle. Further, the vehicle's braking torque percentage is determined based on the optimal duty cycle. Finally, the onboard display unit displays the malfunction and the vehicle's braking torque percentage in real time.

[0120] Therefore, this invention, on the one hand, determines the optimal duty cycle for the current vehicle state based on vehicle state parameters and a braking torque duty cycle table. It can determine the initial optimal duty cycle according to different vehicle states, and then control vehicle braking based on the optimal duty cycle, effectively avoiding braking failure or sudden torque changes, thus significantly improving driving safety. On the other hand, the control logic proposed in this invention requires no complex modeling operations, has strong anti-interference capabilities, wide adaptability, and can be implemented without adding new physical hardware, making it easy to mass-produce and deploy.

[0121] Figure 3This is a schematic diagram of a retarder fault control device provided by the present invention. The present invention is at least applicable to control scenarios involving retarders after oil pressure sensor failure. This retarder fault control device can be implemented using software and / or hardware. Figure 3 As shown, the retarder fault control device includes at least:

[0122] The acquisition module 110 is used to acquire vehicle status parameters and braking torque duty cycle table when the oil pressure sensor malfunctions.

[0123] The first determining module 120 is used to determine the basic value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table.

[0124] The second determining module 130 is used to determine the optimal duty cycle based on the duty cycle base value and vehicle state parameters.

[0125] The operation control module 140 is used to control the retarder to continue working based on the optimal duty cycle.

[0126] Optionally, the vehicle status parameters include at least the retarder gear, current vehicle speed, brake pedal status, retarder oil temperature, and coolant temperature;

[0127] Also includes:

[0128] The fault diagnosis module 150 is used to obtain the working status of the oil pressure sensor, so as to determine whether the oil pressure sensor has a working fault based at least on the working status.

[0129] Optionally, the first determining module 120 is specifically used for:

[0130] The first duty cycle is obtained based on the braking torque duty cycle table under the current retarder gear; and the second duty cycle is determined based on the current vehicle speed and the first duty cycle; and the brake pedal state is determined to be in the depressed state; and when the brake pedal state is depressed, the second duty cycle is multiplied by a third proportional coefficient to determine the base value of the duty cycle.

[0131] Optionally, the operation control module 140 is also specifically used for:

[0132] When the brake pedal is not depressed, the retarder continues to operate based on the second duty cycle control.

[0133] Optionally, the first determining module 120 is further specifically used for:

[0134] The system determines whether the current vehicle speed is less than a first vehicle speed threshold; and, if the current vehicle speed is less than the first vehicle speed threshold, determines the first duty cycle as the second duty cycle; and, if the current vehicle speed is not less than the first vehicle speed threshold, continues to determine whether the current vehicle speed is less than the second vehicle speed threshold; and, if the current vehicle speed is less than the second vehicle speed threshold, multiplies the first duty cycle by a first proportional coefficient to determine the second duty cycle; and, if the current vehicle speed is not less than the second vehicle speed threshold, multiplies the first duty cycle by a second proportional coefficient to determine the second duty cycle.

[0135] The second vehicle speed threshold is greater than the first vehicle speed threshold.

[0136] Optionally, the second determining module 130 is specifically used for:

[0137] The third duty cycle is determined based on the retarder oil temperature and the base duty cycle value; and it is determined whether the coolant temperature is greater than the preset temperature threshold; and when the coolant temperature is greater than the preset temperature threshold, the third duty cycle is multiplied by the third proportional coefficient to determine the optimal duty cycle.

[0138] Optionally, the operation control module 140 is also specifically used for:

[0139] When the coolant temperature is not greater than the preset temperature threshold, the retarder continues to work based on the third duty cycle control.

[0140] Optionally, the second determining module 130 is further specifically used for:

[0141] The system determines whether the retarder oil temperature is lower than a first preset oil temperature; and, if the retarder oil temperature is lower than the first preset oil temperature, it lowers the duty cycle base value by a first preset range to obtain a third duty cycle; and, if the retarder oil temperature is not lower than the first preset oil temperature, it continues to determine whether the retarder oil temperature is lower than a second preset oil temperature; and, if the retarder oil temperature is lower than the second preset oil temperature, it determines the duty cycle base value as a third duty cycle; and, if the retarder oil temperature is not lower than the second preset oil temperature, it continues to determine whether the retarder oil temperature is lower than a third preset oil temperature; and, if the retarder oil temperature is lower than the third preset oil temperature, it lowers the duty cycle base value by a second preset range to obtain a third duty cycle; and, if the retarder oil temperature is not lower than the third preset oil temperature, it determines the duty cycle base value of a preset percentage as the third duty cycle.

[0142] Among them, the third preset oil temperature is greater than the second preset oil temperature, which is greater than the first preset oil temperature.

[0143] Optionally, it also includes:

[0144] The vehicle display module 160 is used to determine the percentage of vehicle braking torque based on the optimal duty cycle; and to display the working fault and the percentage of vehicle braking torque in real time using the vehicle display unit.

[0145] The technical solution provided by this invention firstly acquires vehicle status parameters and a braking torque duty cycle table through an acquisition module when the oil pressure sensor malfunctions; secondly, a first determining module determines the basic value of the duty cycle under the current vehicle status based on the vehicle status parameters and the braking torque duty cycle table; then, a second determining module determines the optimal duty cycle based on the basic value of the duty cycle and the vehicle status parameters; finally, a working control module controls the retarder to continue working based on the optimal duty cycle.

[0146] Therefore, this invention, on the one hand, determines the optimal duty cycle for the current vehicle state based on vehicle state parameters and a braking torque duty cycle table. It can determine the initial optimal duty cycle according to different vehicle states, and then control vehicle braking based on the optimal duty cycle, effectively avoiding braking failure or sudden torque changes, thus significantly improving driving safety. On the other hand, the control logic proposed in this invention requires no complex modeling operations, has strong anti-interference capabilities, wide adaptability, and can be implemented without adding new physical hardware, making it easy to mass-produce and deploy.

[0147] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A retarder fault control method, characterized in that, At least including: S1. When the oil pressure sensor malfunctions, acquire vehicle status parameters and braking torque duty cycle table. S2. Determine the basic value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table; S3. Determine the optimal duty cycle based on the duty cycle baseline value and the vehicle state parameters; S4. Based on the optimal duty cycle, the retarder continues to operate.

2. The retarder fault control method according to claim 1, characterized in that, The vehicle status parameters include at least the retarder gear, current vehicle speed, brake pedal status, retarder oil temperature, and coolant temperature. Before step S1, the following is also included: S11. Obtain the operating status of the oil pressure sensor, so as to determine whether the oil pressure sensor has a malfunction based at least on the operating status.

3. The retarder fault control method according to claim 2, characterized in that, Step S2 specifically includes: S21. Obtain the first duty cycle under the current retarder gear based on the braking torque duty cycle table; S22. Determine the second duty cycle based on the current vehicle speed and the first duty cycle; S23. Determine whether the brake pedal is in a depressed state; S24. If the brake pedal is in the depressed state, the second duty cycle is multiplied by the third proportional coefficient to determine the base value of the duty cycle.

4. The retarder fault control method according to claim 3, characterized in that, Following step S23, the following is also included: S25. If the brake pedal is in an unpressed state, the retarder is controlled to continue working based on the second duty cycle.

5. The retarder fault control method according to claim 3, characterized in that, Step S22 specifically includes: S221. Determine whether the current vehicle speed is less than the first vehicle speed threshold. S222. If the current vehicle speed is less than the first vehicle speed threshold, then the first duty cycle is determined as the second duty cycle. S223. If the current vehicle speed is not less than the first vehicle speed threshold, then continue to determine whether the current vehicle speed is less than the second vehicle speed threshold. S224. If the current vehicle speed is less than the second vehicle speed threshold, the first duty cycle is multiplied by the first proportional coefficient to determine the second duty cycle. S225. If the current vehicle speed is not less than the second vehicle speed threshold, then the first duty cycle is multiplied by the second proportional coefficient to determine the second duty cycle; Wherein, the second vehicle speed threshold is greater than the first vehicle speed threshold.

6. The retarder fault control method according to claim 2, characterized in that, Step S3 specifically includes: S31. Determine the third duty cycle based on the retarder oil temperature and the aforementioned duty cycle baseline value; S32. Determine whether the temperature of the coolant is greater than a preset temperature threshold. S33. If the coolant temperature is greater than the preset temperature threshold, the third duty cycle is multiplied by the third proportional coefficient to determine the optimal duty cycle.

7. The retarder fault control method according to claim 6, characterized in that, Following step S32, the following is also included: S34. If the coolant temperature is not greater than the preset temperature threshold, the retarder is controlled to continue working based on the third duty cycle.

8. The retarder fault control method according to claim 5, characterized in that, Step S31 specifically includes: S311. Determine whether the retarder oil temperature is lower than the first preset oil temperature; S312. If the retarder oil temperature is lower than the first preset oil temperature, the duty cycle base value is lowered by the first preset range to obtain a third duty cycle. S313. If the retarder oil temperature is not lower than the first preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the second preset oil temperature. S314. If the retarder oil temperature is lower than the second preset oil temperature, then the duty cycle base value is determined as the third duty cycle. S315. If the retarder oil temperature is not lower than the second preset oil temperature, then continue to determine whether the retarder oil temperature is lower than the third preset oil temperature. S316. If the retarder oil temperature is lower than the third preset oil temperature, the duty cycle base value is adjusted down by a second preset range to obtain the third duty cycle. S317. If the retarder oil temperature is not less than the third preset oil temperature, then the preset ratio of the duty cycle base value is determined as the third duty cycle. The third preset oil temperature is greater than the second preset oil temperature, which is greater than the first preset oil temperature.

9. The retarder fault control method according to claim 1, characterized in that, Following step S4, the following is also included: S5. Determine the percentage of vehicle braking torque based on the optimal duty cycle; S6. The on-board display unit is used to display the working fault and the percentage of the vehicle's braking torque in real time.

10. A retarder fault control device, characterized in that, The device is used to perform the retarder fault control method as described in any one of claims 1-9; The device includes at least: The acquisition module is used to acquire vehicle status parameters and braking torque duty cycle table when the oil pressure sensor malfunctions. The first determining module is used to determine the basic value of the duty cycle under the current vehicle state based on the vehicle state parameters and the braking torque duty cycle table; The second determining module is used to determine the optimal duty cycle based on the duty cycle base value and the vehicle state parameters; The operation control module is used to control the retarder to continue working based on the optimal duty cycle.

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