Pneumatic exhaust brake speed control method under domain control architecture

Abstract

The present invention relates to a pneumatic exhaust brake speed regulation method under a domain control architecture, comprising an engine torque control sub-process, a gearbox AMT control sub-process, and an engine exhaust brake speed regulation sub-process; the gearbox AMT control sub-process is used to determine and send ATM request information; the engine torque control sub-process is used to perform torque limiting operations on the engine, including an engine torque limiting mode; the engine exhaust brake speed regulation sub-process is used to perform speed regulation operations and exhaust brake operations on the engine, including a speed regulation preparation stage and a speed regulation stage; the engine torque control sub-process, the gearbox AMT control sub-process, and the engine exhaust brake speed regulation sub-process are in a parallel processing relationship. The present invention fully compensates for the hysteresis of the pneumatic exhaust brake response; realizes that the exhaust brake assists in the engine torque unloading stage; when the gearbox directly exits the torque unloading and enters the torque return, the exhaust brake can be exited in time to avoid the engine stalling; and optimizes the engine speed regulation time.

Description

Technical Field

[0001] The present invention relates to the field of AMT whole vehicle control technology, and in particular to a pneumatic exhaust brake speed regulation method under a domain control architecture. Background Art

[0002] As the intelligent automotive electronic and electrical architecture supports the rapid development of the "four modernizations" of future vehicles and in-vehicle software, domain controllers are increasingly valued as a platform for integrating vehicle-level software functions. Under the domain control architecture, the functions of the gearbox and engine are fully integrated, and the interaction between the gearbox and engine signals is more convenient. Under the domain control architecture, some functions involving multi-controller interaction are also more convenient to implement.

[0003] With the development of vehicle technology, AMT can improve driver comfort and ease of operation, while also having good economy and reliability, and is becoming increasingly popular.

[0004] The existing AMT vehicle has three main stages in the process of upshifting, namely, torque unloading, speed regulation, and torque return. With current technology, during the speed regulation process, the engine speed mainly depends on the inertia of the engine flywheel to reduce the engine speed.

[0005] The defects of the prior art are:

[0006] 1. In the prior art AMT shifting and speed regulation process, if the engine speed is too slow, there will be a large speed difference between the master and slave plates when the gearbox clutch is engaged, which will cause the gearbox gear shifting to be not smooth;

[0007] 2. In the prior art AMT shifting and speed regulation process, if the engine speed regulation is too slow, there will be a large speed difference between the master and slave plates when the gearbox clutch is engaged, which will bring another problem, that is, the large speed difference will bring impact to the clutch, affecting the life of the clutch;

[0008] 3. Since the engine speed regulation time in the prior art is too long, the power interruption time of the whole vehicle is long and the shifting quality is poor. Summary of the invention

[0009] In view of the above problems, the present invention provides a pneumatic exhaust brake speed control method under a domain control architecture, which aims to fully compensate for the lag of the pneumatic exhaust brake response; to achieve exhaust brake-assisted torque unloading in the engine torque unloading stage; when the gearbox directly exits torque unloading and enters torque return, the exhaust brake can be exited in time to avoid engine stalling; and the engine speed control time is optimized.

[0010] To solve the above problems, the technical solution provided by the present invention is:

[0011] A pneumatic exhaust brake speed control method under a domain control architecture includes an engine torque control sub-process, a gearbox AMT control sub-process, and an engine exhaust brake speed control sub-process; wherein:

[0012] The gearbox AMT control sub-process is used to determine and issue ATM request information based on working condition information;

[0013] The engine torque control sub-process is used to perform torque limiting operation on the engine according to the ATM request information, including an engine torque limiting mode;

[0014] The engine exhaust brake speed regulation sub-process is used to perform speed regulation and exhaust brake operations on the engine according to the ATM request information, including a speed regulation preparation phase and a speed regulation phase;

[0015] The engine torque control sub-process, the transmission AMT control sub-process, and the engine exhaust brake speed regulation sub-process are in a parallel processing relationship.

[0016] Preferably, the working condition information includes current vehicle status information, own fault status information, clutch status information, gearbox shift mechanism status information, gearbox input shaft speed information, engine speed control target speed information, gearbox actual gear information, gearbox target gear information;

[0017] The ATM request information includes gear shift torque unloading request information, speed regulation request information, and torque return request information.

[0018] Preferably, the transmission AMT control sub-process specifically includes the following steps:

[0019] Sa100. Identify the current state information of the gearbox shift mechanism, and then perform the following operations according to the identification result:

[0020] If the current state information of the gearbox shift mechanism indicates that the gearbox is at an upshift point, the gearbox AMT control sub-process is started; and then Sa200 is executed;

[0021] If the current state information of the gearbox shift mechanism is not that the gearbox is at an upshift point, return to and execute Sa100 again;

[0022] Sa200. Determine whether the AMT requests to unload the torque; then perform the following operations based on the determination result:

[0023] If the AMT requests torque unloading, the gear shift torque unloading request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time;

[0024] If the AMT does not request torque shedding, or it is determined according to the current vehicle status information that the current AMT requires to exit torque shedding, or it is determined according to the self-fault status information that the current AMT requires to exit torque shedding, then execute Sa400;

[0025] Sa300. Determine whether the AMT requests speed adjustment; then perform the following operations based on the determination result:

[0026] If the AMT requests speed regulation, the speed regulation request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time;

[0027] If the AMT does not request speed regulation, Sa400 is executed;

[0028] Sa400. Determine whether the AMT requests a twist back; then perform the following operations based on the determination result:

[0029] If the AMT requests a twist back, the twist back request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time;

[0030] If the AMT does not request torque return, the transmission AMT control sub-process ends.

[0031] Preferably, the engine torque control sub-process specifically includes the following steps:

[0032] Sb100. Receive the ATM request information from the gearbox AMT control subprocess, and then parse the ATM request information; then perform the following operations according to the parsing result of the ATM request information:

[0033] If the parsing result of the ATM request information is a gear shift torque unloading request information, execute Sb200;

[0034] If the parsing result of the ATM request information is speed adjustment request information, execute Sb300;

[0035] If the parsing result of the ATM request information is a reversal request information, execute Sb400;

[0036] Sb200 sets the engine to enter the engine torque limiting mode; then determines whether the engine torque unloading is completed; then according to the determination result, perform the following operations:

[0037] If the engine torque is unloaded, execute Sa300;

[0038] If the engine torque unloading is not completed, execute Sa200;

[0039] Sb300. Setting the engine to exit the engine torque limiting mode;

[0040] Sb400 sets the engine to enter the engine torque limit mode; then determines whether the engine torque back is completed; then according to the determination result, performs the following operations:

[0041] If the engine torque back is completed, the engine torque control sub-process ends;

[0042] If the engine torque back is not completed, execute Sa400;

[0043] The engine torque limiting mode is specifically: the engine gradually stops injecting fuel until the engine output torque drops to 0.

[0044] Preferably, the engine exhaust brake speed regulation sub-process specifically includes the following steps:

[0045] Sc100. Receive the ATM request information from the gearbox AMT control subprocess, and then parse the ATM request information; then perform the following operations according to the parsing result of the ATM request information:

[0046] If the parsing result of the ATM request information is a gear shift torque unloading request information, executing Sc200;

[0047] If the parsing result of the ATM request information is speed adjustment request information, execute Sc300;

[0048] If the parsing result of the ATM request information is a reversal request information, execute Sc400;

[0049] Sc200. Set the exhaust brake to enter the speed regulation preparation stage;

[0050] Sc300. Set the exhaust brake to enter the speed regulation stage; then determine whether the engine speed regulation is completed; then perform the following operations based on the determination result:

[0051] If the engine speed regulation is completed, the exhaust brake is set to exit the speed regulation stage, and Sa400 is executed at the same time;

[0052] If the engine speed regulation is not completed, return to and execute the speed regulation phase again.

[0053] Preferably, the speed regulation preparation stage specifically includes the following steps:

[0054] Sd100. Get the exhaust brake valve type; the exhaust brake valve type includes a pneumatic exhaust brake valve and a proportional exhaust brake valve;

[0055] Sd200. Perform the following operations according to the exhaust brake valve type:

[0056] If the exhaust brake valve type is the pneumatic exhaust brake valve, executing the pneumatic exhaust brake valve speed regulation preparation process;

[0057] If the exhaust brake valve type is the proportional exhaust brake valve, a proportional exhaust brake valve speed regulation preparation process is performed.

[0058] Preferably, the pneumatic exhaust brake valve speed regulation preparation process specifically comprises the following steps:

[0059] Sda100. Get the cylinder pressure and transmission slip ratio;

[0060] Sda200. Compare the transmission slip rate with a manually preset transmission slip rate threshold, and then perform the following operations according to the comparison result:

[0061] If the transmission slip ratio is lower than the transmission slip ratio threshold, return to and execute Sda100 again;

[0062] If the transmission slip ratio is not lower than the transmission slip ratio threshold, executing Sda300;

[0063] Sda300 compares the gas cylinder pressure with a manually preset gas cylinder pressure threshold, and then performs the following operations according to the comparison result:

[0064] If the gas cylinder pressure is higher than the gas cylinder pressure threshold, execute Sda400;

[0065] If the gas cylinder pressure is lower than the gas cylinder pressure threshold, executing Sda500;

[0066] Sda400. According to the cylinder pressure table, obtain the exhaust brake valve delayed closing time; then wait for the exhaust brake valve delayed closing time, close the exhaust brake valve;

[0067] Sda500. Obtain the exhaust brake valve advance closing time according to the cylinder pressure table; then advance the exhaust brake valve advance closing time and close the exhaust brake valve.

[0068] Preferably, the proportional exhaust brake valve speed regulation preparation process specifically comprises the following steps:

[0069] Sdb100. Obtain the cylinder pressure, transmission slip ratio, engine torque, and exhaust manifold pressure; the target exhaust manifold pressure and actual exhaust manifold pressure are included; the target exhaust manifold pressure is obtained by subtracting the actual transmission gear information from the transmission target gear information, and then combined with the engine speed to find the difference obtained by manually pre-set two-dimensional mapping table.

[0070] Sdb200. According to the transmission slip rate and the engine torque, a first open-loop term is obtained by looking up a table;

[0071] Sdb300. Calculate the first closed-loop term based on the difference between the target exhaust manifold pressure and the actual exhaust manifold pressure;

[0072] Sdb400. Add the first open-loop term and the first closed-loop term to obtain a first proportional exhaust brake valve PWM.

[0073] Preferably, the speed regulation stage specifically comprises the following steps:

[0074] Se100. Get the exhaust brake valve type;

[0075] Se200. Perform the following operations according to the exhaust brake valve type:

[0076] If the exhaust brake valve type is the pneumatic exhaust brake valve, executing the pneumatic exhaust brake valve speed regulation process;

[0077] If the exhaust brake valve type is the proportional exhaust brake valve, executing the proportional exhaust brake valve speed regulation process;

[0078] The pneumatic exhaust brake valve speed regulation process specifically includes the following steps:

[0079] Sea100. Get engine speed and target speed;

[0080] Sea200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated;

[0081] Sea300. According to the engine speed, the engine speed reduction rate is calculated;

[0082] Sea400. According to the difference between the engine speed and the target speed control speed and the engine speed reduction rate, determine whether the exhaust brake valve is exited; then perform the following operations according to the determination result:

[0083] If the determination result is that the exhaust brake valve is withdrawn, the switch of the exhaust brake valve is closed;

[0084] If the exhaust brake valve is not released, return to and execute Sea100 again.

[0085] Preferably, the proportional exhaust brake valve speed regulation process specifically comprises the following steps:

[0086] Seb100. Obtain exhaust brake pressure, target speed control speed and engine speed;

[0087] Seb200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated;

[0088] Seb300. According to the engine speed, the engine speed reduction rate is calculated;

[0089] Seb400. According to the exhaust brake pressure and the engine speed reduction rate, a second open-loop item is obtained by looking up a table;

[0090] Seb500. The difference between the engine speed and the target speed is used to calculate the exhaust brake valve PID item;

[0091] Seb600. Add the second open-loop term to the exhaust brake valve PID term to obtain a second proportional exhaust brake valve PWM.

[0092] Compared with the prior art, the present invention has the following advantages: 1. Since the present invention takes advantage of the domain control architecture and fully integrates the gearbox and engine control, the exhaust brake is involved in the gearbox upshift and torque unloading stage, and the signal transmission time is short, so that the hysteresis of the pneumatic exhaust brake response can be fully compensated;

[0093] 2. Since the present invention is compatible with pneumatic switch type and proportional exhaust brake valve, exhaust brake assists in unloading torque during the engine torque unloading stage;

[0094] 3. Since the present invention can accommodate the influence of the vehicle status and the gearbox failure on the gear shift, when the gearbox directly exits the torque unloading and enters the torque return, the exhaust brake can be exited in time to avoid the engine stalling;

[0095] 4. Since the present invention realizes rapid and stable regulation of the engine speed through exhaust brake closed-loop control, the engine speed regulation time can be optimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0096] Figure 1 It is a schematic diagram of the control framework structure of a specific embodiment of the present invention;

[0097] Figure 2 A schematic diagram of an engine upshift and downshift according to a specific embodiment of the present invention;

[0098] Figure 3 A schematic diagram of a method flow chart of a specific embodiment of the present invention;

[0099] Figure 4 It is a schematic diagram of the control principle of the proportional exhaust brake valve in the speed regulation preparation stage according to a specific embodiment of the present invention;

[0100] Figure 5It is a schematic diagram of the control principle of the proportional exhaust brake valve in the speed regulation stage according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0101] The present invention is further explained below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0102] It should be noted in advance that if Figure 1 As shown, it is a control framework of the pneumatic exhaust brake speed control method under the domain control architecture involved in the present invention; under this control framework, it includes three parts: engine torque control, transmission AMT control and engine exhaust brake speed control, all of which are integrated inside the domain controller; exhaust brake participates in regulation during the engine torque unloading stage; this control framework solves the problem of exhaust brake participation in speed regulation responsiveness through the full integration of the above three parts, controls the engine speed to quickly drop to the target speed required for AMT speed regulation and maintains it within a smaller speed fluctuation range, thereby optimizing the upshift speed regulation time.

[0103] It is necessary to further explain that if Figure 2 As shown in the figure, for the whole vehicle, due to the needs of braking, parking, seats, etc., the whole vehicle will be equipped with an air tank, and the whole vehicle will have sufficient air supply. Based on cost considerations, the engine exhaust brake mostly chooses pneumatic configuration, which can control the opening of the exhaust brake valve by adjusting the air pressure supplied by the vehicle air tank.

[0104] But if Figure 2 As shown in the figure, for the pneumatic exhaust brake valve, since the exhaust brake valve response depends on the compressed air drive, it takes a certain amount of time for the compressed air to be transmitted in the pipeline and to build up the air pressure. During the gear shifting process, if the intervention starts at the speed regulation stage, the speed regulation stage will end when the exhaust brake valve just starts to respond. The exhaust brake valve cannot optimize the speed regulation, but will affect the next torque return stage.

[0105] This is one of the core invention purposes of the present invention, that is, to develop a pneumatic exhaust brake speed control method under a domain control architecture, using the exhaust brake principle to quickly reduce the engine speed.

[0106] like Figure 3 As shown, a pneumatic exhaust brake speed control method under a domain control architecture includes an engine torque control sub-process, a gearbox AMT control sub-process, and an engine exhaust brake speed control sub-process; wherein:

[0107] The transmission AMT control sub-process is used to determine and issue ATM request information based on operating condition information.

[0108] In this specific embodiment, the operating condition information includes the current vehicle status information, its own fault status information, clutch status information, transmission shift mechanism status information, transmission input shaft speed information, engine speed control target speed information, transmission actual gear information, and transmission target gear information.

[0109] ATM request information includes gear shift torque unloading request information, speed regulation request information, and torque return request information.

[0110] The engine torque control sub-process is used to perform torque limiting operation on the engine according to the ATM request information, including the engine torque limiting mode.

[0111] The engine exhaust brake speed control sub-process is used to perform speed control and exhaust brake operations on the engine according to the ATM request information, including the speed control preparation stage and the speed control stage.

[0112] The engine torque control sub-process, the transmission AMT control sub-process, and the engine exhaust brake speed regulation sub-process are in a parallel processing relationship.

[0113] In this specific embodiment, the gearbox AMT control sub-process specifically includes the following steps:

[0114] Sa100. Identify the current status information of the gearbox selector and shift mechanism through the domain controller, and then perform the following operations according to the identification structure:

[0115] If the current transmission shift mechanism status information indicates that the transmission is at the upshift point, the transmission AMT control sub-process is started; and then Sa200 is executed.

[0116] If the current transmission shift mechanism status information does not indicate that the transmission is at an upshift point, the process returns to and executes Sa100 again.

[0117] Sa200. Determine whether the AMT requests to unload the torque; then perform the following operations based on the determination result:

[0118] If the AMT requests torque unloading, the gear shift torque unloading request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time.

[0119] If the AMT does not request torque shedding, or determines that the current AMT requires exiting torque shedding based on the current vehicle status information, or determines that the current AMT requires exiting torque shedding based on its own fault status information, execute Sa400.

[0120] Sa300. Determine whether the AMT requests speed adjustment; then perform the following operations based on the determination result:

[0121] If the AMT requests speed regulation, speed regulation request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time.

[0122] If the AMT does not request speed adjustment, Sa400 is executed.

[0123] Sa400. Determine whether the AMT requests a twist back; then perform the following operations based on the determination result:

[0124] If the AMT requests a torque return, the torque return request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time.

[0125] If the AMT does not request torque return, the transmission AMT control sub-process ends.

[0126] In this specific embodiment, the engine torque control sub-process specifically includes the following steps:

[0127] Sb100 receives the ATM request information from the gearbox AMT control subprocess, and then parses the ATM request information; then, according to the parsing result of the ATM request information, performs the following operations:

[0128] If the parsing result of the ATM request information is the gear shift torque unloading request information, Sb200 is executed.

[0129] If the parsing result of the ATM request information is speed adjustment request information, Sb300 is executed.

[0130] If the parsing result of the ATM request information is the reversal request information, Sb400 is executed.

[0131] Sb200. Set the engine to enter the engine torque limit mode; then determine whether the engine torque unloading is completed; then perform the following operations based on the determination result:

[0132] If the engine torque unloading is complete, execute Sa300.

[0133] If engine torque unloading is not complete, execute Sa200.

[0134] Sb300. Set the engine to exit the engine torque limiting mode.

[0135] Sb400. Set the engine to enter the engine torque limit mode; then determine whether the engine torque return is completed; then perform the following operations based on the determination result:

[0136] If the engine torque back is completed, the engine torque control sub-routine ends.

[0137] If engine twist back is not complete, execute Sa400.

[0138] The engine torque limiting mode is specifically as follows: the engine gradually stops injecting fuel until the engine output torque drops to 0.

[0139] In this specific embodiment, the engine exhaust brake speed regulation sub-process specifically includes the following steps:

[0140] Sc100. Receive the ATM request information from the gearbox AMT control subprocess, and then parse the ATM request information; then perform the following operations according to the parsing result of the ATM request information:

[0141] If the parsing result of the ATM request information is a gear shift torque unloading request information, execute Sc200.

[0142] It should be noted that when the engine exhaust brake speed regulation sub-process finds that the parsed result of the received ATM request information is a gear shift torque unloading request information, the exhaust brake regulation side is immediately arranged to start building air pressure to improve the responsiveness of the speed regulation stage.

[0143] If the parsing result of the ATM request information is speed adjustment request information, execute Sc300.

[0144] It should be noted that when the engine exhaust brake speed control sub-process finds that the parsed result of the received ATM request information is a speed control request information, due to the previous preparation stage, the exhaust brake can be quickly intervened at this time, so as to quickly reduce the engine speed.

[0145] If the parsing result of the ATM request information is the reversal request information, execute Sc400.

[0146] It should be noted that when the engine exhaust brake speed control sub-process finds that the parsed result of the received ATM request information is a torque return request information, the engine exhaust brake speed control sub-process needs to ensure that the exhaust brake is exited normally. Therefore, the engine torque control sub-process enters the torque limiting mode again, and injects oil through the injector to slowly restore the engine torque to the level before the gear shift.

[0147] Sc200. Set the exhaust brake to enter the speed regulation preparation stage.

[0148] It should be noted that the speed regulation preparation stage mainly takes into account the time delay of the exhaust brake valve response, which is compensated in the transmission torque unloading stage to ensure that the exhaust brake can respond quickly in the transmission speed regulation stage.

[0149] On the other hand, considering that the gearbox will exit the gear shifting process due to comprehensive consideration of the vehicle status and its own fault status during the torque process, the exhaust brake valve cannot be directly closed during the torque unloading stage. This will cause the exhaust brake valve to close too much during the gear shifting exit, causing the engine to stall.

[0150] In this specific embodiment, the speed regulation preparation stage specifically includes the following steps:

[0151] Sd100. Get the exhaust brake valve type; the exhaust brake valve types include pneumatic exhaust brake valve and proportional exhaust brake valve.

[0152] Sd200. Perform the following operations according to the exhaust brake valve type:

[0153] If the exhaust brake valve type is a pneumatic exhaust brake valve, perform the pneumatic exhaust brake valve speed adjustment preparation procedure.

[0154] It should be noted that the main purpose of this stage is to establish the compressed air circuit pressure for exhaust brake valve regulation. Since the pneumatic exhaust brake valve can only realize full open and full closed functions, and it takes a certain amount of time to go from fully open to fully closed, the timing of the intervention of the pneumatic exhaust brake valve needs to be determined based on the cylinder pressure and the transmission slip rate.

[0155] It needs to be further explained that it is emphasized again that the main purpose of this stage is to establish the compressed air circuit pressure for exhaust brake valve regulation; however, unlike the pneumatic exhaust brake valve, the proportional exhaust brake valve can also assist in torque unloading due to its adjustable proportion. Therefore, if the vehicle is equipped with a proportional exhaust brake valve, a different process needs to be adopted.

[0156] In this specific embodiment, the pneumatic exhaust brake valve speed regulation preparation process specifically includes the following steps:

[0157] Sda100. Get the cylinder pressure and transmission slip ratio.

[0158] Sda200 compares the transmission slip rate with the manually preset transmission slip rate threshold, and then performs the following operations based on the comparison result:

[0159] If the transmission slip ratio is lower than the transmission slip ratio threshold, then return to and execute Sda100 again.

[0160] If the transmission slip ratio is not less than the transmission slip ratio threshold, Sda300 is executed.

[0161] Sda300 compares the cylinder pressure with the manually preset cylinder pressure threshold, and then performs the following operations based on the comparison result:

[0162] If the cylinder pressure is higher than the cylinder pressure threshold, Sda400 is executed.

[0163] If the tank pressure is below the tank pressure threshold, Sda500 is executed.

[0164] Sda400. Obtain the delayed closing time of the exhaust brake valve according to the cylinder pressure table; then close the exhaust brake valve after waiting for the delayed closing time of the exhaust brake valve.

[0165] Sda500. Obtain the exhaust brake valve advance closing time according to the cylinder pressure table; then advance the exhaust brake valve advance closing time and close the exhaust brake valve.

[0166] If the exhaust brake valve type is a proportional exhaust brake valve, perform the proportional exhaust brake valve speed control preparation procedure.

[0167] like Figure 4 As shown, in this specific embodiment, the proportional exhaust brake valve speed regulation preparation process specifically includes the following steps:

[0168] Sdb100. Obtains the cylinder pressure, transmission slip ratio, engine torque, and exhaust manifold pressure; including the target exhaust manifold pressure and the actual exhaust manifold pressure; the target exhaust manifold pressure is obtained by subtracting the actual transmission gear information from the transmission target gear information, and then finding the difference in a manually preset two-dimensional mapping table in combination with the engine speed.

[0169] Sdb200. According to the transmission slip ratio and engine torque, the first open-loop item is obtained by looking up the table.

[0170] Sdb300. The first closed-loop term is obtained by calculating the difference between the target exhaust manifold pressure and the actual exhaust manifold pressure.

[0171] Sdb400. Add the first open-loop term to the first closed-loop term to obtain the first proportional exhaust brake valve PWM.

[0172] It should be noted that when calculating the first proportional exhaust brake valve PWM, one cannot only look at the theoretical value, but also needs to take into account the exhaust manifold temperature and the boost temperature not exceeding the limit.

[0173] Sc300. Set the exhaust brake to enter the speed regulation stage; then determine whether the engine speed regulation is completed; then perform the following operations based on the determination result:

[0174] If the engine speed regulation is completed, the exhaust brake is set to exit the speed regulation stage and Sa400 is executed at the same time.

[0175] If the engine speed regulation is not completed, go back and execute the speed regulation phase again.

[0176] In this specific embodiment, the speed regulation stage specifically includes the following steps:

[0177] It should be noted that the main task of the speed regulation stage is to quickly reduce the engine speed and control the engine speed to fluctuate within a small range around the target speed.

[0178] On the other hand, since the exhaust brake has already built up the air pressure during the speed regulation preparation stage, the exhaust brake can respond quickly at this time.

[0179] It should be noted that since the pneumatic exhaust brake valve can only realize full opening and full closing functions; and at this stage, the main control is the withdrawal of the exhaust brake valve; therefore, the timing of the push-out of the pneumatic exhaust brake valve needs to be determined based on the difference between the engine speed and the target speed control speed, and the engine speed reduction rate.

[0180] It should be further explained that, since the proportional exhaust brake valve can achieve proportional regulation, if the vehicle is equipped with a proportional exhaust brake valve, closed-loop control can be achieved in the speed regulation stage.

[0181] Se100. Get the exhaust brake valve type;

[0182] Se200. Perform the following operations according to the exhaust brake valve type:

[0183] If the exhaust brake valve type is a pneumatic exhaust brake valve, perform the pneumatic exhaust brake valve speed adjustment procedure.

[0184] In this specific embodiment, the pneumatic exhaust brake valve speed regulation process specifically includes the following steps:

[0185] Sea100. Get the engine speed and target speed.

[0186] Sea200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated.

[0187] Sea300. Calculate the engine speed drop rate based on the engine speed.

[0188] Sea400. determines whether the exhaust brake valve is exited based on the difference between the engine speed and the target speed control speed and the engine speed drop rate; then performs the following operations based on the determination result:

[0189] If the exhaust brake valve is determined to be out of service, the exhaust brake valve switch is closed.

[0190] If the exhaust brake valve is not released, return to and execute Sea100 again.

[0191] If the exhaust brake valve type is a proportional exhaust brake valve, execute the proportional exhaust brake valve speed control process.

[0192] like Figure 5 As shown, in this specific embodiment, the proportional exhaust brake valve speed regulation process specifically includes the following steps:

[0193] Seb100. Obtain exhaust brake pressure, target speed control speed and engine speed.

[0194] Seb200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated.

[0195] Seb300. Calculate the engine speed reduction rate based on the engine speed.

[0196] Seb400. According to the exhaust brake pressure and the engine speed reduction rate, the second open-loop item is obtained by looking up the table.

[0197] Seb500. The difference between the engine speed and the target speed control speed is used to calculate the exhaust brake valve PID item.

[0198] Seb600. Add the second open-loop term to the exhaust brake valve PID term to obtain the second proportional exhaust brake valve PWM.

[0199] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0200] The disclosed embodiments are described above to enable any person skilled in the art to implement or use the present invention. Various modifications of these embodiments are obvious to those skilled in the art, and the general principles defined herein may also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0201] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

[0202] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pneumatic exhaust brake speed control method under a domain control architecture, characterized in that: It includes engine torque control sub-process, gearbox AMT control sub-process, engine exhaust brake speed regulation sub-process; among which: The gearbox AMT control sub-process is used to determine and issue ATM request information based on working condition information; The engine torque control sub-process is used to perform torque limiting operation on the engine according to the ATM request information, including an engine torque limiting mode; The engine exhaust brake speed regulation sub-process is used to perform speed regulation and exhaust brake operations on the engine according to the ATM request information, including a speed regulation preparation phase and a speed regulation phase; The engine torque control sub-process, the gearbox AMT control sub-process, and the engine exhaust brake speed regulation sub-process are in a parallel processing relationship; The ATM request information includes gear shift torque unloading request information, speed regulation request information, and torque return request information; The transmission AMT control sub-process specifically includes the following steps: Sa100. Identify the current state information of the gearbox shift mechanism, and then perform the following operations according to the identification result: If the current state information of the gearbox shift mechanism indicates that the gearbox is at an upshift point, the gearbox AMT control sub-process is started; and then Sa200 is executed; If the current state information of the gearbox shift mechanism is not that the gearbox is at an upshift point, return to and execute Sa100 again; Sa200. Determine whether the AMT requests to unload the torque; then perform the following operations based on the determination result: If the AMT requests torque unloading, the gear shift torque unloading request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time; If the AMT does not request torque shedding, or it is determined according to the current vehicle status information that the current AMT requires to exit torque shedding, or it is determined according to the self-fault status information that the current AMT requires to exit torque shedding, then execute Sa400; Sa300. Determine whether the AMT requests speed adjustment; then perform the following operations based on the determination result: If the AMT requests speed regulation, the speed regulation request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time; If the AMT does not request speed regulation, Sa400 is executed; Sa400. Determine whether the AMT requests a twist back; then perform the following operations based on the determination result: If the AMT requests a twist back, the twist back request information is sent to the engine torque control sub-process and the engine exhaust brake speed regulation sub-process at the same time; If the AMT does not request torque return, the transmission AMT control sub-process ends.

2. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 1 is characterized in that: The working condition information includes current vehicle status information, own fault status information, clutch status information, transmission shift mechanism status information, transmission input shaft speed information, engine speed control target speed information, transmission actual gear information, and transmission target gear information.

3. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 2 is characterized in that: The engine torque control sub-process specifically includes the following steps: Sb100. Receive the ATM request information from the gearbox AMT control subprocess, and then parse the ATM request information; then perform the following operations according to the parsing result of the ATM request information: If the parsing result of the ATM request information is a gear shift torque unloading request information, execute Sb200; If the parsing result of the ATM request information is speed adjustment request information, execute Sb300; If the parsing result of the ATM request information is a reversal request information, execute Sb400; Sb200 sets the engine to enter the engine torque limiting mode; then determines whether the engine torque unloading is completed; then according to the determination result, perform the following operations: If the engine torque is unloaded, execute Sa300; If the engine torque unloading is not completed, execute Sa200; Sb300. Setting the engine to exit the engine torque limiting mode; Sb400 sets the engine to enter the engine torque limit mode; then determines whether the engine torque back is completed; then according to the determination result, performs the following operations: If the engine torque back is completed, the engine torque control sub-process ends; If the engine torque back is not completed, execute Sa400; The engine torque limiting mode is specifically: the engine gradually stops injecting fuel until the engine output torque drops to 0.

4. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 3 is characterized in that: The engine exhaust brake speed regulation sub-process specifically includes the following steps: Sc100. Receive the ATM request information from the gearbox AMT control subprocess, and then parse the ATM request information; then perform the following operations according to the parsing result of the ATM request information: If the parsing result of the ATM request information is a gear shift torque unloading request information, executing Sc200; If the parsing result of the ATM request information is speed adjustment request information, execute Sc300; If the parsing result of the ATM request information is a reversal request information, execute Sc400; Sc200. Set the exhaust brake to enter the speed regulation preparation stage; Sc300. Set the exhaust brake to enter the speed regulation stage; then determine whether the engine speed regulation is completed; then perform the following operations based on the determination result: If the engine speed regulation is completed, the exhaust brake is set to exit the speed regulation stage, and Sa400 is executed at the same time; If the engine speed regulation is not completed, return to and execute the speed regulation phase again.

5. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 4 is characterized in that: The speed regulation preparation stage specifically includes the following steps: Sd100. Get the exhaust brake valve type; the exhaust brake valve type includes a switch exhaust brake valve and a proportional exhaust brake valve; Sd200. Perform the following operations according to the exhaust brake valve type: If the exhaust brake valve type is the switch type exhaust brake valve, executing the switch type exhaust brake valve speed regulation preparation process; If the exhaust brake valve type is the proportional exhaust brake valve, a proportional exhaust brake valve speed regulation preparation process is performed.

6. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 5 is characterized in that: The on-off exhaust brake valve speed regulation preparation process specifically includes the following steps: Sda100. Get the cylinder pressure and transmission slip ratio; Sda200. Compare the transmission slip rate with a manually preset transmission slip rate threshold, and then perform the following operations according to the comparison result: If the transmission slip ratio is lower than the transmission slip ratio threshold, return to and execute Sda100 again; If the transmission slip ratio is not lower than the transmission slip ratio threshold, executing Sda300; Sda300 compares the gas cylinder pressure with a manually preset gas cylinder pressure threshold, and then performs the following operations according to the comparison result: If the gas cylinder pressure is higher than the gas cylinder pressure threshold, execute Sda400; If the gas cylinder pressure is lower than the gas cylinder pressure threshold, executing Sda500; Sda400. According to the cylinder pressure table, obtain the exhaust brake valve delayed closing time; then wait for the exhaust brake valve delayed closing time, close the exhaust brake valve; Sda500. Obtain the exhaust brake valve advance closing time according to the cylinder pressure table; then advance the exhaust brake valve advance closing time and close the exhaust brake valve.

7. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 6 is characterized in that: The proportional exhaust brake valve speed regulation preparation process specifically includes the following steps: Sdb100. Obtaining cylinder pressure, transmission slip ratio, engine torque, exhaust manifold pressure; including target exhaust manifold pressure and actual exhaust manifold pressure; the target exhaust manifold pressure is obtained by subtracting the difference between the actual transmission gear information and the target gear information of the transmission, and then finding the manually preset two-dimensional mapping table in combination with the engine speed; Sdb200. According to the transmission slip rate and the engine torque, a first open-loop term is obtained by looking up a table; Sdb300. Calculate the first closed-loop term based on the difference between the target exhaust manifold pressure and the actual exhaust manifold pressure; Sdb400. Add the first open-loop term and the first closed-loop term to obtain a first proportional exhaust brake valve PWM.

8. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 7 is characterized in that: The speed regulation stage specifically comprises the following steps: Se100. Get the exhaust brake valve type; Se200. Perform the following operations according to the exhaust brake valve type: If the exhaust brake valve type is the switch type exhaust brake valve, executing the switch type exhaust brake valve speed regulation process; If the exhaust brake valve type is the proportional exhaust brake valve, executing the proportional exhaust brake valve speed regulation process; The on-off exhaust brake valve speed regulation process specifically comprises the following steps: Sea100. Get engine speed and target speed; Sea200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated; Sea300. According to the engine speed, the engine speed reduction rate is calculated; Sea400. According to the difference between the engine speed and the target speed control speed and the engine speed reduction rate, determine whether the exhaust brake valve is exited; then perform the following operations according to the determination result: If the determination result is that the exhaust brake valve is withdrawn, the switch of the exhaust brake valve is closed; If the exhaust brake valve is not released, return to and execute Sea100 again.

9. The pneumatic exhaust brake speed control method under the domain control architecture according to claim 8 is characterized in that: The proportional exhaust brake valve speed regulation process specifically comprises the following steps: Seb100. Obtain exhaust brake pressure, target speed control speed and engine speed; Seb200. According to the engine speed and the target speed regulating speed, the difference between the engine speed and the target speed regulating speed is calculated; Seb300. According to the engine speed, the engine speed reduction rate is calculated; Seb400. According to the exhaust brake pressure and the engine speed reduction rate, a second open-loop item is obtained by looking up a table; Seb500. The difference between the engine speed and the target speed is used to calculate the exhaust brake valve PID item; Seb600. Add the second open-loop term to the exhaust brake valve PID term to obtain a second proportional exhaust brake valve PWM.

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