Vehicle combined brake control method, device, equipment, storage medium and product

Abstract

The application discloses a kind of vehicle combined brake control method, device, equipment, storage medium and product, belong to vehicle brake control technical field, mainly solve the brake performance recession caused by traditional hydraulic brake overheating failure in heavy load long downhill working condition and the problems of multi-brake system energy distribution and thermal load management.Technical scheme points: in response to electric brake handle operation activation drive motor brake, real-time detection power system state;Drive motor overspeed when synchronously step by step promotes hydraulic retarder gear and activates engine cylinder brake;When engine overspeed, hydraulic retarder and engine cylinder brake output brake force according to set proportion and brake in coordination;Non-overrun state continues drive motor brake;In response to foot brake pedal operation activation hydraulic brake.The method of the application can realize safe braking, prevent overheating failure and improve energy recovery efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle brake control. More particularly, the present application relates to a vehicle combined brake control method, device, equipment, storage medium and product. BACKGROUND

[0002] In the operation process of a vehicle, especially a non-highway transport vehicle, heavy load and long downhill working conditions pose a severe challenge to the braking system. Due to the large load, long and continuous slope of such vehicles, the hydraulic braking system needs to work for a long time and under high load. When the hydraulic braking system repeatedly or continuously applies braking force, a large amount of heat is generated between the friction plate and the brake disc / drum due to intense friction. Due to the limitation of heat dissipation conditions, the temperature of the brake rises sharply, and a significant thermal recession phenomenon occurs. Specifically, the thermal stability of the friction material decreases, resulting in a decrease in the friction coefficient, and the hydraulic oil may be blocked due to high temperature, ultimately causing a significant attenuation of the braking torque or even a temporary failure. This not only directly weakens the braking ability of the vehicle, but in extreme cases, it can completely lose the control of deceleration, posing a serious safety hazard.

[0003] To alleviate the thermal load of the hydraulic braking system, some vehicles are equipped with auxiliary braking devices, such as hydraulic retarders or engine cylinder brakes. However, there are the following key difficulties in the prior art: First, various auxiliary braking systems (such as independent retarders, exhaust brakes or motor brakes) often operate independently or only perform simple sequential superposition control, lacking a dynamic coordination mechanism based on the state of the whole vehicle. Second, when facing changing slope conditions, vehicle speed and load, it is difficult to intelligently allocate the braking force proportion and intervention timing among different auxiliary braking systems. For example, when the drive motor speed is close to the limit but has not reached the trigger threshold of the traditional retarder, or in an emergency situation where the engine speed suddenly rises, the system cannot quickly and accurately coordinate multiple auxiliary braking sources for optimal combined intervention. Third, in the application of energy recovery type auxiliary braking (such as motor braking), its output is limited by the state of charge (SOC) of the battery and the current motor speed range. If these states cannot be adjusted in real time and seamlessly connected with other auxiliary braking, energy recovery cannot be maximized or the satisfaction of braking force demand cannot be ensured.

[0004] In addition, at the driver operation level, the existing auxiliary braking method usually requires the driver to frequently manually switch or combine different braking devices (such as handles, switches), which not only increases the operation complexity, but also is more likely to cause operation delay or failure in the long and continuous downhill driving environment.

[0005] Therefore, how to solve the efficient coordination and state adaptive control of multiple braking sources is a key bottleneck to improve the downhill safety of such vehicles. SUMMARY

[0006] The application aims to provide a vehicle combined braking control method, device, equipment, storage medium and product to at least solve the above problems.

[0007] In order to achieve the purpose of the application and other advantages, a vehicle combined braking control method is provided, comprising the following steps: step one: in response to the triggering operation of the driver on the electric brake handle, the vehicle controller activates the drive motor braking; at the same time, the vehicle state parameters monitored by the sensor are obtained, and it is judged whether the vehicle state parameters exceed the threshold value; step two: if the vehicle state parameters do not exceed the threshold value, the drive motor continues to brake; if the vehicle state parameters exceed the threshold value, the auxiliary braking system is synchronously controlled to intervene; step three: in response to the triggering operation of the driver on the foot brake pedal, the hydraulic braking system is activated; wherein the vehicle state parameters include the drive motor speed and / or the engine speed; when it is detected that the drive motor speed exceeds the threshold value, the hydraulic retarder is synchronously controlled to gradually increase the braking gear and the engine cylinder braking is activated; and / or when it is detected that the engine speed exceeds the threshold value, the emergency braking request sent by the engine control unit is synchronously received, and the engine cylinder braking and the hydraulic retarder are triggered to output collaborative braking force in a set proportion.

[0008] Preferably, the vehicle controller sets the upper limit of the target negative torque change rate of the hydraulic retarder and the engine cylinder braking, and monitors the actual output torque and its change rate of the hydraulic retarder and the engine cylinder braking in real time; if the actual torque change rate of any braking source exceeds the upper limit of the target negative torque change rate, the torque request of the other braking source is temporarily frozen or slowed down until the actual torque change rates of both return to the range of the upper limit of the target negative torque change rate.

[0009] Preferably, the set proportion is variable, that is, the vehicle controller obtains the vehicle slope signal, vehicle speed signal and load signal in real time; according to the slope signal, vehicle speed signal and load signal, the target output proportion of the hydraulic retarder and the engine cylinder braking is dynamically calculated and adjusted in combination with the pre-set braking efficiency map; wherein in the working condition of increasing slope or increasing vehicle speed, the target output proportion of the hydraulic retarder is increased; in the working condition of decreasing slope, decreasing vehicle speed or decreasing load, the target output proportion of the engine cylinder braking is increased.

[0010] Preferably, when the vehicle state parameters are all not over the threshold value and the drive motor continues to brake, the energy recovery intensity is dynamically adjusted according to the energy storage unit state and the drive motor speed, the target negative torque value of the drive motor and the actual executed negative torque value are obtained; if the actual executed negative torque value of the drive motor does not reach the target negative torque value, the hydraulic retarder and the engine cylinder braking are activated for braking force compensation.

[0011] Preferably, the method further comprises: if the driving motor actually executes a negative torque value lower than the target negative torque value for a predetermined time threshold, generating a hydraulic braking demand prompt information.

[0012] Preferably, the method further comprises: the driving motor controller determines an optimal energy recovery interval according to the state of charge of the energy storage unit and a driving motor speed threshold; and automatically adjusts the regenerative intensity in the optimal energy recovery interval to achieve the target negative torque value.

[0013] Preferably, the driving motor controller, when determining the optimal energy recovery interval and automatically adjusting the regenerative intensity, further comprises: obtaining a state of charge change rate of the energy storage unit in real time; if the absolute value of the state of charge change rate exceeds a preset threshold, predicting a state of charge trend in a future predetermined time window based on the current state of charge and the change rate thereof; dynamically correcting the optimal energy recovery interval according to the predicted state of charge trend, and adjusting the regenerative intensity based on the corrected interval.

[0014] The application also provides a vehicle combined braking control device, which adopts the vehicle combined braking control method described above, and comprises: an operation and parameter monitoring module, which is configured to activate the driving motor braking in response to the triggering operation of the electric brake handle by the driver; at the same time, obtain the vehicle state parameters monitored by the sensors and determine whether the vehicle state parameters exceed the threshold; an auxiliary braking module, which is configured to intervene in braking when the vehicle state parameters exceed the threshold; a hydraulic braking module, which is configured to activate the hydraulic braking system in response to the triggering operation of the foot brake pedal by the driver; wherein the vehicle state parameters include the driving motor speed and / or the engine speed; when it is detected that the driving motor speed exceeds the threshold, the hydraulic retarder is controlled to gradually increase the braking gear and the engine cylinder braking is activated; and / or when it is detected that the engine speed exceeds the threshold, the engine control unit sends an emergency braking request, which is received synchronously to trigger the engine cylinder braking and the hydraulic retarder to output the cooperative braking force in a set proportion.

[0015] Preferably, the method further comprises: the vehicle control unit sets the upper limit of the target negative torque change rate of the hydraulic retarder and the engine cylinder braking, and monitors the actual output torque and the change rate thereof of the hydraulic retarder and the engine cylinder braking in real time; if the actual torque change rate of any braking source exceeds the upper limit of the target negative torque change rate thereof, the torque request of the other braking source is temporarily frozen or slowed down until the actual torque change rates of both return to the range of the upper limit of the target negative torque change rate.

[0016] Preferably, the set ratio is variable, namely: the vehicle control unit obtains a vehicle slope signal, a vehicle speed signal and a load signal in real time; according to the slope signal, the vehicle speed signal and the load signal, and in combination with a preset brake efficiency map, the target output ratio of the hydraulic retarder and the engine cylinder brake is dynamically calculated and adjusted; wherein, in the working condition of increasing slope or increasing speed, the target output ratio of the hydraulic retarder is increased; in the working condition of decreasing slope, decreasing speed or decreasing load, the target output ratio of the engine cylinder brake is increased.

[0017] Preferably, when none of the vehicle state parameters exceeds the threshold value, the driving motor continues to brake, and the method further comprises: dynamically adjusting the energy recovery intensity according to the energy storage unit state and the driving motor speed, obtaining a driving motor target negative torque value and a feedback actual execution negative torque value; if the driving motor actual execution negative torque value does not reach the target negative torque value, activating the hydraulic retarder and the engine cylinder brake to perform brake force compensation.

[0018] Preferably, the method further comprises: if the driving motor actual execution negative torque value continuously falls below the target negative torque value and reaches a predetermined time threshold value, generating a hydraulic brake demand prompt information.

[0019] Preferably, the dynamically adjusting the energy recovery intensity according to the energy storage unit state and the driving motor speed further comprises: the driving motor controller determines an optimal energy recovery interval according to the state of charge of the energy storage unit and a driving motor speed threshold value; and automatically adjusting the energy feeding intensity in the optimal energy recovery interval to achieve the target negative torque value.

[0020] Preferably, when determining the optimal energy recovery interval and automatically adjusting the energy feeding intensity, the driving motor controller further comprises: obtaining a state of charge change rate of the energy storage unit in real time; if the absolute value of the state of charge change rate exceeds a preset threshold value, predicting a state of charge trend in a future predetermined time window based on the current state of charge and the change rate thereof; dynamically correcting the optimal energy recovery interval according to the predicted state of charge trend, and adjusting the energy feeding intensity based on the corrected interval.

[0021] The application further provides an electronic device, comprising: at least one processor, and a memory in communication connection with the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the vehicle joint brake control method.

[0022] The application further provides a storage medium having a computer program stored thereon, and the program is executed by a processor to implement the vehicle joint brake control method.

[0023] The application further provides a computer program product comprising computer programs / instructions which, when executed by a processor, implement the vehicle combined braking control method described above.

[0024] The application at least includes the following beneficial effects:

[0025] First, the layered response mechanism significantly improves the reliability and safety of the braking system. After the electric brake handle is triggered, the drive motor braking is activated preferentially and the vehicle power system state is monitored in real time to ensure the timeliness of the braking intervention. When the drive motor overspeed is detected, the hydraulic retarder gear is gradually raised synchronously and the engine cylinder braking is activated to avoid the failure risk caused by the overload of a single braking source; when the engine overspeed is detected, the braking force is output in a predetermined proportion to realize the hard protection of the power system. The energy recovery intensity is dynamically adjusted under the non-overrun state, and the braking force compensation mechanism is combined to maximize the recovery of kinetic energy while ensuring the braking force demand. The independent response of the foot brake pedal ensures the redundancy of emergency braking. The overall scheme effectively solves the problems of braking overheating and decay in heavy load long downhill conditions and low efficiency of multi-system cooperation, prolongs the service life of the braking components and improves the driving safety.

[0026] Second, the dynamic determination mechanism of the "optimal energy recovery interval" significantly optimizes the energy recovery efficiency and system stability. The drive motor controller determines the high-efficiency recovery interval in real time based on the state of charge of the energy storage unit and the speed threshold to avoid energy waste or battery damage in the boundary state (such as high / low charge) under the traditional fixed strategy. The energy feedback intensity is automatically adjusted within the optimal interval to ensure the accurate achievement of the target negative torque and reduce unnecessary auxiliary braking intervention. This design not only improves the energy recovery rate in downhill conditions, but also reduces the battery large current charging and discharging impact through smooth torque output, prolongs the service life of the energy storage system, reduces the hydraulic braking compensation frequency, and relieves the braking thermal load pressure.

[0027] Third, the prediction mechanism based on the state of charge change rate effectively improves the robustness and adaptability of the energy recovery control. By monitoring the state of charge change rate in real time and predicting its trend, the system can identify the rapid fluctuation risk of the state of charge (such as sudden change caused by strong recovery or driving) in advance and dynamically correct the optimal energy recovery interval. This design solves the problems of recovery intensity lag or frequent braking force compensation caused by the distortion of the instantaneous value of the state of charge in the traditional method, ensuring the continuous and stable output of the target negative torque. Especially in the critical region of the state of charge (such as near full charge or low charge), the system oscillation is significantly reduced to avoid recovery interruption or accidental activation of hydraulic braking, thereby improving the driving smoothness and optimizing the energy recovery efficiency.

[0028] Fourth, by setting the torque change rate upper limit and cross coordination strategy, the problem of smoothness caused by response difference of multiple braking sources is solved. The vehicle controller monitors the actual torque change rate of the hydraulic retarder and engine cylinder braking in real time. When the response rate of any braking source exceeds the threshold, the torque request of the other braking source is dynamically frozen or slowed down, and the response synchronization is forced to be realized. This mechanism effectively suppresses the superposition or deficiency of instantaneous braking force caused by the difference in response time of hydraulic system, engine cycle and electric control, especially in emergency braking conditions to avoid vehicle jerk. At the same time, it ensures the linear growth of torque in the process of cooperative braking, improves the braking comfort, and prevents mechanical impact or component damage caused by sudden torque change.

[0029] Fifth, the variable proportion mechanism greatly improves the working condition adaptability and energy efficiency ratio of the braking system. Based on real-time slope, vehicle speed and load signals, the vehicle controller dynamically adjusts the output proportion of the hydraulic retarder and engine cylinder braking in combination with the braking efficiency map: increase the proportion of hydraulic retarder at high speed / large slope / heavy load to take advantage of its high-speed braking; Increase the proportion of engine cylinder braking at low speed / light load / small slope to reduce hydraulic loss. This design overcomes the defects of low efficiency of hydraulic retarder in low speed working condition or insufficient engine braking force in high speed working condition caused by fixed proportion, and ensures efficient generation of braking force in all working conditions. At the same time, it optimizes the engine fuel economy, reduces noise and wear, and avoids unnecessary friction braking intervention.

[0030] Sixth, the brake force deficiency warning mechanism enhances the active safety protection capability of the system. By continuously comparing the target negative torque with the actual execution value, when it is detected that the brake force gap exceeds the threshold time continuously, the hydraulic braking demand prompt is generated. This design provides the driver with a critical reaction window, avoiding the risk of sudden brake failure caused by gradual brake force decay. Especially in long downhill or continuous braking scenarios, early warning can prompt the driver to enable the main hydraulic braking system in time, prevent overloading of the auxiliary braking system, ensure reliable triggering of the braking redundancy mechanism, and significantly reduce the probability of accidents.

[0031] Seventh, the joint braking control method has achieved remarkable technical effect in the test stage. The test data shows that compared with the traditional pure hydraulic braking system, this method can effectively reduce the brake temperature rise and prolong the service life of the brake pad. In terms of energy recovery, the priority strategy of drive motor braking increases the energy recovery rate in downhill working condition, greatly improving the operating economy of the mine truck. In terms of operation, by converting the complex braking logic into a simple interaction of "handle priority + automatic supplement", the driver's operation steps are simplified, effectively reducing the risk of human error. Especially in long downhill scenarios, the system automatically maintains the accuracy of the target vehicle speed to ± 1.5 km / h, completely solving the problem of brake decay caused by frequent brake application in traditional braking methods.

[0032] Additional advantages, objects, and features of the application will be apparent from the following description, taken in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0033] The application will be further described with reference to the following examples, in order that the application might be better understood.

[0034] It should be understood that the terms such as "have", "contain", and "include" used herein do not exclude the presence or addition of one or more other elements.

[0035] It should be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified.

[0036] In a first aspect, the application provides a vehicle combined braking control method.

[0037] According to one embodiment of the application, the vehicle combined braking control method operates according to the following flow:

[0038] Initial triggering stage: the driver pulls the electric brake handle, and the vehicle controller immediately activates the drive motor braking, and real-time acquisition of motor speed, engine speed and battery state of charge;

[0039] Over-speed response stage (heavy load downhill working condition): when it is detected that the drive motor speed exceeds the safety threshold, two operations are performed simultaneously: sending a step-by-step gear lifting instruction to the hydraulic retarder (each step lifting interval ≤ 0.5 seconds), and activating the engine cylinder braking through a hard-wired signal;

[0040] Over-speed emergency braking (critical working condition): if the engine speed breaks through the critical value, the CAN bus request sent by the engine control unit is received, the hydraulic retarder is controlled to output a negative torque to a preset reference value, and the engine cylinder braking is instructed to output the maximum braking force, for example, the retarder outputs 74% negative torque, and the engine cylinder braking outputs 100% braking force;

[0041] Dynamic compensation stage (normal downhill working condition): when neither the motor nor the engine is out of limit, the drive motor controller calculates the optimal energy recovery interval according to the battery state of charge and the speed threshold, and automatically adjusts the energy feeding intensity; if the actual motor braking force is lower than the target negative torque value, the hydraulic retarder and the cylinder braking are simultaneously triggered to fill the braking gap;

[0042] Redundancy guarantee stage: when the driver steps on the foot brake pedal, the hydraulic braking system is immediately activated and is not limited by the foregoing logic.

[0043] In the existing combined braking control, a hierarchical braking strategy is often used: after the driver pulls the electric brake handle, the vehicle controller only activates the drive motor braking; when the motor speed exceeds the threshold, the hydraulic retarder and engine cylinder braking are sequentially started.

[0044] Compared with the existing combined braking control, the present embodiment uses synchronous intervention instead of sequential start, synchronously executes the hydraulic retarder gear shift and cylinder braking activation, eliminates the braking response empty window period, and shortens the key braking build-up time compared with the existing method; uses proportional cooperation instead of fixed superposition, distributes the hydraulic retarder and cylinder braking force proportionally according to the engine overspeed, and avoids insufficient mechanical braking force in high-speed working conditions; uses dynamic compensation instead of passive limitation, instantly compensates for the motor braking force gap through the hydraulic retarder and cylinder braking when the battery is in a high state of charge, and maintains the stability of the target vehicle speed.

[0045] According to another embodiment of the application, the drive motor controller collects battery state of charge and drive motor speed data in real time. The recovery interval boundary is dynamically adjusted according to the state of charge classification result: it is expanded to the motor peak torque zone in low state of charge, and it is contracted to the lower limit of the constant power zone in high state of charge. At the same time, the interval width is optimized in combination with the speed threshold, and the widest efficient recovery band is set in the medium speed zone. Within the dynamically defined optimal interval, the system automatically adjusts the regenerative current intensity: if the actual vehicle speed is lower than the target value, the recovery torque is linearly increased; if the battery temperature abnormally rises, the output power is stepped down. Finally, the actual torque and the target value of the motor braking are continuously compared, and the compensation mechanism is started when the deviation exceeds the limit.

[0046] The existing method often uses a table-based single-parameter control, and the drive motor controller only determines the recovery intensity threshold by looking up the table according to the current state of charge of the battery, and maintains a fixed torque output. This method has obvious defects when the state of charge changes rapidly: when the vehicle enters the initial stage of long downhill, the state of charge of the battery is low, and the system recovers energy at the maximum intensity; but as the state of charge continues to rise to the preset threshold, the recovery intensity is suddenly cut off, the braking force is instantaneously attenuated, and the hydraulic retarder is forced to intervene to compensate. This step change causes the vehicle to be obviously jerky. At the same time, this strategy ignores the influence of speed, and still recovers at high load in the low speed interval of the motor, which not only has low energy conversion efficiency, but also aggravates the mechanical braking wear due to torque fluctuations.

[0047] Compared with the existing method, the present embodiment uses a state of charge and speed double-parameter dynamic recovery interval, replaces the traditional single-parameter fixed threshold, and fundamentally avoids the braking force mutation in the boundary region; realizes continuous adjustment of the regenerative intensity in the optimal interval, eliminates the step response of the table-based control; and includes the high-efficiency speed range of the motor in the decision model, solving the energy conversion loss problem in the low-speed high-load working condition. These improvements enable the system to adapt to continuous changes in the state of charge and optimize the recovery efficiency throughout the speed range.

[0048] According to another embodiment of the application, the drive motor controller continuously acquires the battery state of charge and calculates its rate of change. When the absolute value of the rate of change exceeds a preset sensitivity threshold, the state of charge trajectory within a certain future time window is predicted based on the current value and the direction of change. If the prediction shows that the upper limit will be reached, the optimal recovery interval is contracted in advance and the regenerative intensity is reduced; if the prediction shows that the lower limit will be reached, the recovery interval is expanded and the intensity is increased. After the optimal interval boundaries are dynamically corrected based on the prediction results, the system smoothly adjusts the actual recovery torque within the interval. The entire process forms a "monitoring, prediction, correction and execution" closed loop until the state of charge rate of change returns to the stable range.

[0049] The existing method often uses real-time feedback control. The drive motor controller detects the current state of charge of the battery every cycle, and if it exceeds the preset threshold, the recovery intensity is immediately reduced. This method can maintain stability when the state of charge changes slowly, but it has serious defects under sudden working conditions: when driving downhill under heavy load, strong recovery causes the state of charge to quickly approach the upper limit, and the system cuts off the recovery when the threshold is reached, at which time the hydraulic retarder needs to urgently make up for the braking force gap, causing the vehicle to jerk; when the state of charge drops sharply due to a sudden drop in driving load, the system needs to re-activate recovery, causing torque steps. More seriously, near the critical point of the state of charge, a small fluctuation triggers repeated switching of the recovery state, accelerating the wear of mechanical braking components.

[0050] Compared with the existing method, the progress of the present embodiment is to replace passive response with trend prediction, capturing the dynamic trend through the rate of change of the state of charge, and adjusting the control strategy in advance before the threshold is reached. This avoids the repeated oscillation of the traditional method in the critical region and eliminates the sudden demand for braking force compensation. At the same time, the prediction mechanism makes the system adapt to the inertial characteristics of the battery response, such as predicting the state of charge rising curve when strong recovery starts, gradually reducing the recovery intensity instead of a threshold-triggered sudden drop, ensuring the continuity of torque output.

[0051] According to another embodiment of the application, the vehicle controller sets an upper limit for the target negative torque rate of change for the hydraulic retarder and the engine cylinder brake. When the system enters the cooperative braking mode, the instantaneous change rates of the actual output torques of the two are monitored in real time. If it is detected that the torque change rate of the hydraulic retarder exceeds its upper limit, the torque increase request of the engine cylinder brake is immediately frozen until the torque change rate of the hydraulic retarder falls within the allowed range; conversely, when the torque change rate of the engine cylinder brake exceeds the threshold, the gear position of the hydraulic retarder is simultaneously suppressed. During the freezing period, the current torque output of the other braking source is maintained, and after the change rates of both sides are stable within the threshold, cooperative increase is restored. This process is executed in a loop until the target braking force is reached.

[0052] The existing method often uses time delay compensation mechanism. The vehicle controller sends brake instructions, and a fixed delay time is preset for the slow hydraulic retarder. The engine cylinder brake is activated immediately. This scheme can run in steady state, but it has fatal defects in dynamic conditions. When the vehicle suddenly enters a steep slope from a flat road, the preset delay time does not match the actual response of the hydraulic retarder, resulting in a dangerous gap when the motor brake has exited and the hydraulic retarder torque has not reached its peak. More seriously, in the alternating braking and acceleration conditions, the fixed delay causes the mechanical brake torque to lag behind the motor brake exit, forming an unexpected drag torque. In actual measurement, this response misalignment makes the longitudinal acceleration of the cab fluctuate beyond the limit.

[0053] Compared with the existing method, the embodiment uses dynamic interlocking instead of static delay. By capturing the torque change rate of each brake source in real time, the output rhythm of other members is actively inhibited when the response is too fast, and synchronous advancement is forced. This not only eliminates the brake force fluctuations caused by fixed parameters in traditional schemes, but more importantly, it adapts to the changes in response characteristics at different temperatures, oil pressures, and speeds. For example, in a low-temperature environment, the viscosity of hydraulic oil increases, and the hydraulic retarder responds more slowly, so the system automatically extends the waiting time for engine cylinder braking. In high-speed conditions, the engine cycle period is shortened, and the change rate threshold is accordingly relaxed. This adaptive coordination fundamentally guarantees the linearity of torque output.

[0054] According to another embodiment of the application, the vehicle controller collects slope sensor signals, vehicle speed signals, and load signals converted from air suspension pressure in real time. A pre-stored brake efficiency map is called, which is calibrated through bench tests to obtain peak efficiency curves of the hydraulic retarder and engine cylinder brake under different slope, speed, and load combinations. Based on real-time signals, the current optimal proportion is calculated by interpolation in the three-dimensional map: for example, when the slope is greater than 8% or the vehicle speed is higher than 60 km / h, the proportion of the hydraulic retarder is increased to the peak efficiency zone; when the slope is less than 3% and the load rate is less than 40%, the proportion of engine cylinder braking is increased to more than 80%. The dynamic proportion instruction is sent synchronously to the hydraulic retarder controller and engine control unit through the CAN bus for execution.

[0055] The existing method often uses a preset fixed proportion to cooperate. The hydraulic retarder and engine cylinder brake always output brake force according to a static proportion. This scheme produces double contradictions when the working conditions change: when the vehicle loaded with ore enters a long downhill, the hydraulic retarder quickly reaches the maximum brake torque, but the fixed proportion limits the engine cylinder brake to output only part of the torque, and the total brake force is not enough to maintain the target speed, forcing the hydraulic brake to intervene prematurely. Conversely, when returning to an uphill section in an empty state, the efficiency of the hydraulic retarder decreases sharply in the low-speed zone, and the system still allocates load according to the fixed proportion, causing the engine cylinder brake to work excessively, resulting in a significant increase in fuel consumption and accelerated aging of the exhaust brake valve due to frequent operation.

[0056] Compared with the prior art, in the embodiment, working condition sensing is used to replace mechanical distribution, and the current braking demand characteristics are accurately identified through three-parameter fusion sensing, for example, in the case of heavy load and steep slope, the hydraulic retarder is automatically strengthened to play the advantage of high speed and large torque; in the case of empty load and gentle slope, the engine cylinder brake is switched to be dominant to utilize the low speed and high efficiency characteristics. More importantly, the engine speed protection logic is embedded in the proportional calculation, and when the speed approaches the red line, the distribution proportion is automatically reduced to avoid the risk of overspeed caused by strong engine in the traditional scheme. The adaptive mechanism makes the cooperative braking truly cover all working conditions.

[0057] According to a further embodiment of the application, the vehicle control unit continuously compares the target negative torque with the actual execution value, and when it is detected that the actual value is lower than the target value and the deviation exceeds the preset tolerance band, a timer is started to accumulate the duration. If the duration reaches a predetermined threshold, a graded warning signal is generated: in the first stage, a yellow warning icon and a buzzer prompt are sent to the instrument panel; in the second stage, a brake efficiency degradation code is uploaded to the fleet management system through the vehicle communication module. During the warning period, the system rechecks the brake force deviation state every second, and if the deviation disappears, the timer is reset; if the deviation continues to expand, the hydraulic brake standby mode is directly activated when the second time threshold is reached.

[0058] In the embodiment, the slowly developing failure trend is accurately identified by capturing the time integral effect of the brake force deviation. For example, in the process of increasing the oil temperature of the hydraulic retarder from 90°C to 120°C, the maximum braking torque is linearly reduced from 3000 Nm to 2500 Nm, and the embodiment can give an early warning when the torque is reduced to 2800 Nm and maintained for a set period of time, so as to give the driver key decision-making time. At the same time, the time threshold mechanism effectively filters the interference of road bumps and other disturbances, avoiding the false alarm problem of traditional instantaneous detection.

[0059] Further, the application also includes, in response to the driver's trigger operation on the accelerator pedal, cutting off the driving motor brake and exiting the hydraulic retarder brake within 40-60 ms, and gradually releasing the engine cylinder brake. The quick exit mechanism triggered by the accelerator optimizes the smoothness and responsiveness of power switching. The driving motor brake and the hydraulic retarder are cut off synchronously within 40-60 ms to realize seamless restoration of driving torque; at the same time, the engine cylinder brake is gradually released to avoid vehicle jerk caused by torque mutation. The design accurately matches the driver's acceleration intention, eliminates the power response delay caused by brake exit lag in traditional systems, and improves the control experience. The gradual release strategy takes into account the engine protection needs, prevents mechanical impact caused by sudden stop of the cylinder brake, and ensures the stability of the power system in the braking and driving conversion.

[0060] In a second aspect, the present application also provides a vehicle combined braking control device, which adopts the vehicle combined braking control method described above, comprising: an operation and parameter monitoring module, which is configured to activate the drive motor braking in response to the triggering operation of the electric brake handle by the driver, and to obtain the vehicle state parameters monitored by the sensors and determine whether the vehicle state parameters exceed the threshold value; an auxiliary braking module, which is configured to intervene in braking when the vehicle state parameters exceed the threshold value; a hydraulic braking module, which is configured to activate the hydraulic braking system in response to the triggering operation of the foot brake pedal by the driver; wherein the vehicle state parameters comprise the drive motor speed and / or the engine speed; when it is detected that the drive motor speed exceeds the threshold value, i.e., the drive motor is in an overspeed state, the hydraulic retarder is controlled to gradually increase the braking gear and the engine cylinder braking is activated; and / or when it is detected that the engine speed exceeds the threshold value, i.e., the engine is in an overspeed state, the engine control unit sends an emergency braking request, which is received synchronously to trigger the engine cylinder braking and the hydraulic retarder to output the cooperative braking force in a set proportion.

[0061] The vehicle combined braking control device adopts the same inventive concept as the vehicle combined braking control method described above, and thus will not be described here.

[0062] In a third aspect, the present application also provides an electronic device, which comprises at least one processor and a memory connected to the at least one processor in communication, wherein the memory stores a vehicle combined braking control program executable by the at least one processor, and the vehicle combined braking control program is executed by the at least one processor to enable the at least one processor to perform the vehicle combined braking control method described above.

[0063] The electronic device can further comprise a communication interface and a bus. The processor, the memory and the communication interface can communicate with each other through the bus. The communication interface can be used for information transmission. The processor can call the vehicle combined braking control program in the memory to perform the vehicle combined braking control method described above. The control instructions in the memory can be implemented in the form of a software functional unit and sold or used as an independent product, and can be stored in a computer readable storage medium.

[0064] In a fourth aspect, the present application also provides a storage medium, which stores a computer program, i.e., the vehicle combined braking control program described above, and the program is executed by the processor to implement the vehicle combined braking control method described above.

[0065] In the fifth aspect, the present application further provides a computer program product comprising computer programs / instructions, which, when executed by a processor, implement the vehicle combined braking control method described above. The computer program product is stored in a storage medium, and comprises one or more instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the vehicle combined braking control method of the present application. The aforementioned storage medium can be a non-transitory storage medium, including a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc., which can store program codes, or can be a transitory storage medium.

[0066] The number of devices and the scale of processing described herein are used to simplify the description of the present application. The application, modification and variation of the vehicle combined braking control method, the vehicle, the electronic device, the storage medium and the computer program product of the present application are obvious to those skilled in the art.

[0067] Although the embodiments of the present application have been disclosed as above, they are not limited to the application and implementation listed in the specification and the embodiments, and can be fully applied to various fields suitable for the present application, and additional modifications can be easily realized by those skilled in the art, and therefore the present application is not limited to specific details, but falls within the general concept defined by the claims and the equivalent scope.

Claims

1. A vehicle combined brake control method characterized by, The method comprises the following steps: Step 1: In response to the driver's trigger operation on the electric brake handle, the vehicle controller activates the drive motor brake; at the same time, the vehicle state parameters monitored by the sensor are obtained, and it is judged whether the vehicle state parameters exceed the threshold value; Step 2: If the vehicle state parameters do not exceed the threshold value, the drive motor continues to brake; if the vehicle state parameters exceed the threshold value, the auxiliary braking system is synchronously controlled to intervene; Step 3: In response to the driver's trigger operation on the foot brake pedal, the hydraulic brake system is activated; wherein, The vehicle state parameters include: drive motor speed and / or engine speed; When it is detected that the drive motor speed exceeds the threshold value, the hydraulic retarder is synchronously controlled to gradually increase the brake gear and activate the engine cylinder brake; and / or when it is detected that the engine speed exceeds the threshold value, the engine control unit sends an emergency braking request, which triggers the engine cylinder brake and the hydraulic retarder to output collaborative braking force in a set proportion.

2. The vehicle integrated brake control method according to claim 1, characterized by, Further comprising: The vehicle controller sets the target negative torque rate upper limit of the hydraulic retarder and the engine cylinder brake, and monitors the actual output torque and its rate of the hydraulic retarder and the engine cylinder brake in real time; If the actual torque rate of any braking source exceeds the target negative torque rate upper limit, the torque request of the other braking source is temporarily frozen or slowed down until the actual torque rates of both return to the target negative torque rate upper limit range.

3. The vehicle integrated brake control method according to claim 1, characterized by, The set proportion is variable, that is: The vehicle controller obtains the vehicle slope signal, vehicle speed signal and load signal in real time; According to the slope signal, vehicle speed signal and load signal, the target output proportion of the hydraulic retarder and the engine cylinder brake is dynamically calculated and adjusted in combination with the pre-set braking efficiency map; Wherein, in the working condition of increasing slope or speed, the target output proportion of the hydraulic retarder is increased; in the working condition of decreasing slope, speed or load, the target output proportion of the engine cylinder brake is increased.

4. The vehicle integrated brake control method according to claim 1, characterized by, When the vehicle state parameters are not all above the threshold value and the drive motor continues to brake, it further comprises: dynamically adjusting the energy recovery intensity according to the energy storage unit state and the drive motor speed, obtaining the drive motor target negative torque value and the feedback actual execution negative torque value; if the drive motor actual execution negative torque value does not reach the target negative torque value, the hydraulic retarder and the engine cylinder brake are activated for braking force compensation.

5. The vehicle integrated brake control method according to claim 4, characterized by Further comprising: If the drive motor actual execution negative torque value continuously falls below the target negative torque value and reaches a predetermined time threshold, a hydraulic brake demand prompt information is generated.

6. The vehicle integrated brake control method according to claim 4, characterized by The dynamic adjustment of the energy recovery intensity according to the energy storage unit state and the drive motor speed further comprises: the drive motor controller determines the optimal energy recovery interval according to the state of charge of the energy storage unit and the drive motor speed threshold; the regenerative intensity is automatically adjusted in the optimal energy recovery interval to achieve the target negative torque value.

7. The vehicle integrated brake control method according to claim 6, characterized by, The driving motor controller further comprises: acquiring the state of charge variation rate of the energy storage unit in real time; if the absolute value of the state of charge variation rate exceeds a preset threshold, predicting the state of charge trend in a future predetermined time window based on the current state of charge and its variation rate; dynamically correcting the optimal energy recovery interval according to the predicted state of charge trend, and adjusting the energy feedback intensity based on the corrected interval.

8. A vehicle integrated brake control device characterized by comprising: It adopts the vehicle combined brake control method of claims 1-7, comprising: An operation and parameter monitoring module is configured to activate the driving motor brake in response to the driver triggering the electric brake handle; at the same time, acquire the vehicle state parameters monitored by the sensor, and determine whether the vehicle state parameters exceed the threshold value; An auxiliary brake module is configured to intervene in braking when the vehicle state parameters exceed the threshold value; A hydraulic brake module is configured to activate the hydraulic brake system in response to the driver triggering the foot brake pedal; wherein The vehicle state parameters include: driving motor speed and / or engine speed; When the driving motor speed is detected to exceed the threshold value, the hydraulic retarder is synchronously controlled to gradually increase the brake gear, and the engine cylinder brake is activated; and / or when the engine speed is detected to exceed the threshold value, the engine control unit sends an emergency brake request, triggering the engine cylinder brake and the hydraulic retarder to output collaborative braking force in a set proportion.

9. The vehicle integrated brake control device according to claim 8, characterized by Further comprising: The vehicle control unit sets the target negative torque variation rate upper limit of the hydraulic retarder and the engine cylinder brake, and monitors the actual output torque and its variation rate of the hydraulic retarder and the engine cylinder brake in real time; If the actual torque variation rate of any brake source exceeds the target negative torque variation rate upper limit, temporarily freeze or slow down the torque request of the other brake source until the actual torque variation rates of both return to the target negative torque variation rate upper limit range.

10. The vehicle integrated brake control device according to claim 8, characterized by The set proportion is variable, i.e.: The vehicle control unit acquires the vehicle slope signal, vehicle speed signal and load signal in real time; According to the slope signal, vehicle speed signal and load signal, dynamically calculate and adjust the target output proportion of the hydraulic retarder and the engine cylinder brake in combination with the preset brake efficiency map; Wherein, in the working condition of increasing slope or speed, the target output proportion of the hydraulic retarder is increased; in the working condition of decreasing slope, speed or load, the target output proportion of the engine cylinder brake is increased.

11. The vehicle integrated brake control device according to claim 8, characterized by When the vehicle state parameters are not all exceeding the threshold value, and the driving motor continues to brake, further comprising: dynamically adjusting the energy recovery intensity according to the energy storage unit state and the driving motor speed, acquiring the driving motor target negative torque value and the actual executed negative torque value; if the actual executed negative torque value of the driving motor does not reach the target negative torque value, activating the hydraulic retarder and the engine cylinder brake to compensate the braking force.

12. The vehicle integrated brake control device according to claim 11, characterized by Further comprising: If the actual executed negative torque value of the driving motor continuously falls below the target negative torque value and reaches a predetermined time threshold, a hydraulic brake demand prompt information is generated.

13. The vehicle integrated brake control device according to claim 11, characterized by The method further comprises: determining, by the drive motor controller, an optimal energy recovery interval according to the state of charge of the energy storage unit and a drive motor speed threshold; and automatically adjusting the regenerative intensity within the optimal energy recovery interval to achieve a target negative torque value.

14. The vehicle integrated brake control device according to claim 13, wherein The method further comprises: obtaining, by the drive motor controller, a rate of change of the state of charge of the energy storage unit in real time; if an absolute value of the rate of change of the state of charge exceeds a preset threshold, predicting a state of charge trend in a future predetermined time window based on a current state of charge and the rate of change thereof; dynamically correcting the optimal energy recovery interval according to the predicted state of charge trend, and adjusting the regenerative intensity based on the corrected interval.

15. An electronic device, characterized by The method comprises: at least one processor, and a memory connected to the at least one processor in communication, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to cause the at least one processor to perform the vehicle combined braking control method of any one of claims 1-7.

16. A storage medium having stored thereon a computer program, characterized in that The program is executed by the processor to implement the vehicle combined braking control method of any one of claims 1-7.

17. Computer program product comprising computer programs / instructions, characterized in that, The computer program / instructions are executed by the processor to implement the vehicle combined braking control method of any one of claims 1-7.