Engine low-air-pressure working condition gear shifting auxiliary speed increasing method and system, vehicle and medium

Abstract

The invention provides a low-pressure working condition gear shifting auxiliary acceleration method and system of an engine, a vehicle and a medium, and belongs to the technical field of engine control. An engine is controlled to be separated from a gearbox, and a main box gear enters a neutral gear state; the gearbox control unit detects that a downshift process is executed and sends a downshift request instruction to the engine control unit; the engine control unit calculates the required fuel injection quantity on the basis of the downshift request instruction in combination with the current operation state information of the engine; based on the needed fuel injection quantity, the needed gas injection quantity and gas injection duration are calculated, high-pressure gas enters a cylinder through an engine gas inlet pipe, and the requirement of the fuel injection quantity is met; and the engine executes the downshift process to drive the gearbox in the no-load state to operate, so that the rotating speed of the gearbox meets the gear shifting requirement. The system can increase the air inflow in the air inlet pipe of the engine in the low-pressure downshift speed regulation process, speed regulation is accelerated, the downshift speed is increased, and the vehicle running requirement is met.

Description

Technical Field

[0001] The present invention belongs to the technical field of engine control, and in particular relates to a method, system, vehicle and medium for assisting speed-up of gear shifting under low-pressure working conditions of an engine. Background Art

[0002] In the existing vehicle up / down gear control process, in low pressure conditions, such as in plateau areas or high altitude environments, the vehicle's up / down gear control will affect the power output. This is because low pressure causes the air to be thin, the engine intake volume is reduced, resulting in a decrease in combustion efficiency, which in turn affects the vehicle's acceleration performance and gear shifting smoothness.

[0003] Currently, when performing gear shifting operations, if the engine torque output is insufficient, it may cause gear shifting delays, increased jerkiness, or even gear shifting failure, seriously affecting the driving experience and vehicle performance.

[0004] For traditional gear shift assist methods, the combustion process is generally optimized by adjusting parameters such as the engine fuel injection amount and the ignition advance angle. However, under low-pressure conditions, the intake volume reduced due to the thin air cannot be replenished, which reduces the engine's combustion efficiency and torque output. The vehicle's fuel injection amount is limited during downshifting, resulting in a delay in the speed increase, affecting the smoothness and response speed of the gear shift. Summary of the invention

[0005] The invention provides a low-pressure working condition gear shift auxiliary speed-up system for an engine. The system can increase the air intake volume inside an engine intake pipe during a low-pressure downshift speed regulation process, accelerate the speed regulation, and increase the downshift speed.

[0006] Methods include:

[0007] S101: determining the downshift execution process according to the road condition, vehicle speed and driving intention;

[0008] S102: Control the engine and the gearbox to separate, so that the main gearbox gear enters the neutral state;

[0009] S103: The transmission control unit detects the execution of the downshift process and sends a downshift request instruction to the engine control unit;

[0010] S104: The engine control unit calculates the required fuel injection amount based on the downshift request instruction and in combination with the current engine operating state information;

[0011] S105: Based on the required fuel injection amount, the required injection amount and injection duration are calculated, so that the high-pressure gas enters the cylinder through the engine intake pipe to meet the fuel injection amount requirement;

[0012] S106: The engine performs a downshift process to drive the transmission in an unloaded state to operate so that the transmission speed reaches the gear shifting requirement.

[0013] It should be further explained that in step S105, based on the intake air volume and the actual intake air volume f(Q TFI4 ,P current ) extra Represents the required jet volume;

[0014] Difference F extra The calculation method is:

[0015]

[0016] f(Q TFI4 ,P current ) is the engine intake flow rate Q TFI4 and the turbine after-intake pressure P current Calculated actual air intake volume;

[0017] f(ΔN,v clutch ) is the speed difference ΔN and clutch engagement speed v calculated based on the actual gear and the target gear clutch The required fuel injection quantity is obtained by looking up the table.

[0018] It should be further explained that the speed difference ΔN is calculated as follows:

[0019] ΔN=N target -N current

[0020] N target is the sleeve speed calculated from the output shaft speed and the auxiliary box speed ratio, N current Gear speed calculated for the countershaft to mainbox speed ratio.

[0021] It should be further explained that the gear speed N calculated by the speed ratio between the countershaft and the main gearbox is current The calculation method is:

[0022] Get the total speed ratio C of the gearbox bsxz ;

[0023] Define the target value N of the output shaft speed after downshifting zmbz ;

[0024] Based on the following calculation method, the engine speed after downshifting is N jdzs ;

[0025] N jdzs =N zmbz ×C bsxz

[0026] Gear speed N calculated by the speed ratio of countershaft to main gearbox current The calculation method is:

[0027] Ncurrent =N fdj ×(C fzsb / C bsxz )

[0028] C fzsb is the speed ratio between the countershaft and the main gearbox;

[0029] N fdj is the engine speed;

[0030] C bsxz is the overall speed ratio of the gearbox.

[0031] It should be further explained that in the method, the required injection volume is calculated by subtracting the required intake volume of the engine from the actual intake volume calculated by the intake pressure and intake flow after the turbine, and the injection duration is obtained by looking up the table based on the gas pressure in the gas tank and the required injection volume.

[0032] It should be further explained that step S101 also includes:

[0033] When the low air pressure is less than the preset air pressure threshold, the air tank is judged to be in the low air pressure available stage;

[0034] The vehicle controller receives the information of the inconsistency between the pre-selected gear and the actual gear from the gearbox control unit, and determines it as the gear shifting stage.

[0035] It should be further explained that, in the method, when the jetting duration is ≥ the preset jetting duration, or the rotation speed difference ΔN is < the preset rotation speed difference threshold, the jetting is stopped.

[0036] The present application also provides a low-pressure working condition gear shifting auxiliary speed-up system for an engine, the system comprising: a vehicle controller, an engine control unit, a transmission control unit, an engine, a solenoid valve, an air compressor and an air storage tank;

[0037] The output end of the air compressor is connected to the air inlet end of the air storage tank, and the jet end of the air storage tank is connected to the air inlet end of the engine through a solenoid valve;

[0038] The engine control unit is connected to the engine to control the engine operation and obtain the engine operation information;

[0039] The gearbox control unit is connected to the gearbox to control the gearbox operation and obtain the gearbox operation information;

[0040] The vehicle controller determines the downshift process based on the road conditions, vehicle speed and driving intention; controls the engine and gearbox to separate, so that the main box gear enters the neutral state;

[0041] The transmission control unit detects the downshift process and sends a downshift request command to the engine control unit;

[0042] The engine control unit calculates the required fuel injection amount based on the downshift request instruction and the current engine operating state information; based on the required fuel injection amount, calculates the required injection amount and injection duration, so that the high-pressure gas enters the cylinder through the engine intake pipe to meet the fuel injection amount requirement;

[0043] The engine executes the downshift process, driving the transmission to operate under no-load condition, so that the transmission speed reaches the shifting requirements.

[0044] According to another embodiment of the present application, a vehicle is provided for implementing the steps of the method for assisting speed-up by shifting gears under low-pressure conditions of the engine.

[0045] According to another embodiment of the present application, a storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for assisting speed-up of the engine under low-pressure working conditions by shifting are implemented.

[0046] It can be seen from the above technical solutions that the present invention has the following advantages:

[0047] The low-pressure working condition gear shifting auxiliary speed-up method of the engine provided in the present application is based on the actual intake volume calculated according to the engine intake flow and the intake pressure after the turbine during the vehicle downshifting process. Therefore, during the vehicle downshifting and speed-up process, the jetting of the high-pressure gas storage tank connected to the engine intake port can be controlled according to the actual intake volume. At the same time, the jetting time is controlled by calculating and controlling the jetting volume. The high-pressure gas enters the cylinder through the engine intake pipe, increasing the intake pressure of the engine and reducing the fuel injection amount limitation caused by the reduction of the intake pressure during the gear shifting process, thereby quickly increasing the speed, reducing the gear shifting speed regulation time, and then increasing the gear shifting speed. This technology greatly improves the transient responsiveness and smoothness of the gear shifting, and optimizes driving comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0049] Figure 1 A flow chart of a method for assisting speed increase by shifting gears under low-pressure conditions of an engine;

[0050] Figure 2 A flow chart of an embodiment of a method for assisting speed increase by shifting gears under low-pressure conditions of an engine;

[0051] Figure 3 A flow chart of another embodiment of a method for assisting speed increase by shifting gears under low-pressure conditions of an engine;

[0052] Figure 4 This is a schematic diagram of the engine's low-pressure working condition gear shifting auxiliary speed-up system. DETAILED DESCRIPTION

[0053] The following will be combined with the attached Figure 1 , the low-pressure working condition gear shifting auxiliary speed-up method of the engine in the embodiment of the present application is described.

[0054] In order to facilitate understanding of the method provided in the embodiment of the present application, the following points are first explained: First, in the embodiment of the present application, "for implementation" may include for direct implementation and for indirect implementation. In the embodiment of the present application, "at least one" refers to one or more, and "multiple" refers to two or more. "And / or" describes the association relationship of the associated objects, indicating that there may be three relationships, for example, A and / or B, which may represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B may be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following (individuals)" or similar expressions thereof refers to any combination of these items, including any combination of single items (individuals) or plural items (individuals). For example, at least one of a, b and c (individuals) may represent: a, or b, or c, or a and b, or a and c, or b and c, or a, b and c, where a, b, c may be single or multiple.

[0055] In the embodiments of the present application, descriptions such as "when...", "in the case of...", "if" and "if" all mean that the vehicle will make corresponding upshifts or downshifts under certain objective circumstances. It does not limit the time, nor does it require the vehicle to make a judgment when implementing it, nor does it mean that there are other limitations.

[0056] The technical solution of the embodiment of the present application can be applied to various vehicles, specifically commercial vehicles. The vehicle can meet the control of the engine based on up and down gears of the National VI emission standard, or meet the control of the engine based on up and down gears of the National V emission standard, etc. During the up and down gear execution, the intake pressure of the engine can be increased, and the fuel injection amount restriction caused by the reduction of the intake pressure of the National VI engine during the gear shifting process can be reduced, thereby quickly increasing the speed, reducing the gear shifting speed regulation time, and then increasing the gear shifting speed.

[0057] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] See also Figure 1 The figure is a flow chart of a method for assisting speed increase by shifting gears under low-pressure conditions of an engine in a specific embodiment, the method comprising:

[0059] S101: Determine the downshift execution process based on the road condition, vehicle speed and driving intention.

[0060] In some embodiments, radar, cameras, or other sensors installed on the vehicle can be used to collect road condition information in real time, including road slope, road wetness, traffic conditions ahead, etc., which can be used as data basis for shifting gears.

[0061] This embodiment also obtains the current vehicle speed through a vehicle speed sensor and compares it with a preset shift speed threshold, and the comparison result can be used as a data basis for the shift.

[0062] This embodiment analyzes the driver's intention to accelerate or decelerate based on the operation of the accelerator pedal and the brake pedal, combined with the driver's driving habits and the vehicle's dynamic response, and then makes a corresponding judgment on whether to shift gears.

[0063] Optionally, the operation of the accelerator pedal and the brake pedal is monitored, including the degree of opening of the pedals, the rate of change, etc. The driver's intention to accelerate or decelerate is analyzed by an algorithm in combination with the driver's driving habits and the vehicle's dynamic response. If it is recognized that the driver wants to accelerate or needs a stronger power output, a downshift operation is prepared.

[0064] It can be seen that this embodiment improves the accuracy and timeliness of gear shifting, ensures that the gear shifting operation meets the current driving needs, enhances the driving smoothness and safety, and reduces power interruption or vehicle loss of control caused by improper gear shifting.

[0065] S102: Control the engine and the gearbox to separate, so that the main box gear enters the neutral state.

[0066] In some embodiments, the driver can operate the clutch and control the disengagement of the clutch through the clutch actuator to disconnect the power transmission between the engine and the transmission.

[0067] After receiving the clutch release signal, the transmission control unit of this embodiment controls the shift mechanism inside the transmission to put the main box gear into a neutral state.

[0068] In this way, stable initial conditions can be provided for subsequent downshift operations, ensuring a smooth shifting process.

[0069] S103: The transmission control unit detects that a downshift process is being executed, and sends a downshift request instruction to the engine control unit.

[0070] In some embodiments, the transmission control unit confirms the start of the downshift process through an internal sensor or receives a signal from other control units. According to the downshift requirement, a downshift request instruction is sent to the engine control unit through the CAN bus or other communication protocols. The coordinated control between the transmission and the engine is realized to ensure the synchronization of the shifting process. The response speed and accuracy of the system are improved, and the shifting delay and error are reduced.

[0071] S104: The engine control unit calculates the required fuel injection amount based on the downshift request instruction and in combination with the current engine operating state information.

[0072] In some embodiments, the engine control unit monitors the operating status of the engine in real time through various sensors installed on the engine, such as a crankshaft position sensor and a throttle position sensor.

[0073] The engine control unit calculates the required fuel injection amount using a preset algorithm based on the downshift request and the current engine speed, load, and temperature information. This ensures that the engine can provide sufficient power output during downshifting to meet the vehicle's acceleration needs, improve fuel economy, and reduce unnecessary fuel consumption and emissions.

[0074] S105: Based on the required fuel injection amount, the required injection amount and injection duration are calculated, so that the high-pressure gas enters the cylinder through the engine intake pipe to meet the fuel injection amount requirement.

[0075] In some embodiments, the required amount of high-pressure gas is calculated based on the amount of fuel injection and the engine intake efficiency, and the injection duration is precisely controlled by controlling the opening time of the solenoid valve for high-pressure gas injection, so that the high-pressure gas enters the engine intake pipe in an appropriate amount.

[0076] This allows the embodiment to provide additional intake pressure, increase the engine intake volume, and thus improve power output, optimize the combustion process, and improve combustion efficiency and power performance.

[0077] S106: The engine performs a downshift process to drive the transmission in an unloaded state to operate so that the transmission speed reaches the gear shifting requirement.

[0078] In some embodiments, the engine adjusts parameters such as the amount of fuel injection and the timing of ignition according to the instructions of the engine control unit to output sufficient power. Driven by the engine power, the gears inside the gearbox begin to rotate and gradually reach a speed that matches the target gear.

[0079] For the shifting operation process, when the transmission speed meets the shifting requirements, the transmission control unit controls the shifting mechanism to complete the shifting operation, ensuring the smoothness and rapidity of the shifting process, reducing power interruption, and improving the vehicle's acceleration performance and driving stability.

[0080] It can be seen that in the present embodiment, during the process of downshifting and speed increase of the vehicle, the vehicle controller controls the jetting of the high-pressure gas tank externally connected to the engine air intake, and at the same time controls the jetting time by calculating and controlling the jetting amount, and the high-pressure gas enters the cylinder through the engine intake pipe, thereby increasing the intake pressure of the engine and reducing the fuel injection amount restriction caused by the reduction of intake pressure during the gear shifting process, thereby assisting the speed increase of the engine during the low-pressure gear shifting condition, and then through precise control strategies and coordinated system work, efficient gear shifting and power increase under low-pressure conditions are achieved, the gear shifting speed regulation time is reduced, and the transient response and smoothness of the gear shifting are improved.

[0081] In an embodiment of the present invention, based on step S105, a possible embodiment is given below to illustrate its specific implementation scheme in a non-limiting manner.

[0082] During the vehicle downshift process, the clutch is first disengaged and the main box gear enters the neutral state, waiting for the differential gear and range gear to complete. When the engine fuel injection is required to increase the speed of the input shaft and the main box gear, the gearbox sends a request command. At this time, the clutch is engaged and the increase in engine fuel injection drives the speed of the gearbox countershaft and main box gear in the no-load state to increase until the speed reaches the shifting requirements.

[0083] The intake air volume of this embodiment and the actual intake air volume f(Q TFI4 ,P current ) extra Generally speaking, the calculation method is:

[0084]

[0085] f(Q TFI4 ,P current ) is the engine intake flow rate Q TFI4 and the turbine after-intake pressure P current Calculated actual air intake volume.

[0086] f(ΔN,v clutch ) is the speed difference ΔN and clutch engagement speed v calculated based on the actual gear and the target gear clutch The required injection amount obtained by looking up the table, f(ΔN,v clutch ) and the ratio of the combustion efficiency η can, to a certain extent, indicate the amount of intake air required for downshifting and speed adjustment.

[0087] Here ΔN is the sliding sleeve speed N calculated by the output shaft speed and the auxiliary box speed ratio target Gear speed N calculated with the countershaft to main gear ratio current difference.

[0088] The speed difference ΔN is calculated as:

[0089] ΔN=N target -N current

[0090] N target is the sleeve speed calculated from the output shaft speed and the auxiliary box speed ratio, N current Gear speed calculated for the countershaft to mainbox speed ratio.

[0091] In some specific embodiments, the output shaft speed is the speed of the final output of the gearbox or transmission system. The auxiliary box speed ratio can provide additional speed ratio changes. Specifically, it is the speed ratio between the two gear sets in the auxiliary box.

[0092] In a gearbox, the sliding sleeve can be used to change the meshing state of the gears, thereby changing the speed ratio. In this embodiment, the movement of the sliding sleeve directly affects the transmission ratio, that is, the position of the sliding sleeve is directly related to the speed ratio.

[0093] In this embodiment, the speed ratio between the countershaft and the main gearbox determines the speed of the gears in different gears. When calculating the speed of a gear on the countershaft, it can be based on the speed ratio associated with the gear and the speed input to the gearbox, that is, the speed of the engine.

[0094] The gears on the layshaft mesh with the gears in the mainbox, which in turn are connected to the output shaft. In this case, the speed ratio from the layshaft gear to the output shaft can be considered as the product of multiple speed ratios.

[0095] In an exemplary embodiment, the engine speed is defined, which is the input speed of the gearbox. The speed ratio is determined based on the gear on the countershaft meshing with the gear in the main section and finding the speed ratio between the two gears. The speed ratio is defined as the ratio of the speeds of the two gears, i.e. the ratio of the speed of the main section gear to the speed of the countershaft gear.

[0096] In a specific embodiment, the gear speed N calculated by the speed ratio of the countershaft to the main gearbox is current The calculation method is:

[0097] Get the total speed ratio C of the gearbox bsxz ;

[0098] Define the target value N of the output shaft speed after downshifting zmbz ;

[0099] Based on the following calculation method, the engine speed after downshifting is N jdzs ;

[0100] N jdzs =N zmbz ×C bsxz

[0101] Gear speed N calculated by the speed ratio of countershaft to main gearbox current The calculation method is:

[0102] N current =N fdj ×(C fzsb / C bsxz )

[0103] C fzsb is the speed ratio between the countershaft and the main gearbox;

[0104] N fdj is the engine speed;

[0105] C bsxz is the overall speed ratio of the gearbox.

[0106] During the vehicle downshift process, based on the actual intake volume calculated according to the engine intake flow and the intake pressure after the turbine, the jet of the high-pressure gas tank connected to the engine intake port can be controlled according to the actual intake volume. At the same time, the jet time is controlled by calculating the jet volume. The high-pressure gas enters the cylinder through the engine intake pipe, increasing the engine's intake pressure and reducing the fuel injection amount limitation caused by the reduction of intake pressure during the gear shifting process, thereby quickly increasing the speed, reducing the gear shifting speed regulation time, and then increasing the gear shifting speed. This technology greatly improves the transient responsiveness and smoothness of gear shifting, and optimizes driving comfort.

[0107] On the basis of the above embodiments, in order to further improve the reliability and smoothness of the low pressure working condition gear shifting auxiliary speed-up method provided by the above embodiments, as Figure 2 As shown, the following is an implementable method. In the following embodiments, when the air pressure is low, it is determined to be the low air pressure function available stage; when the pre-selected gear position sent by the gearbox control unit received by the vehicle controller is inconsistent with the actual gear position, it is determined to be the shifting stage. The low air pressure here can be defined as low air pressure P≤60kpa.

[0108] If the engine fuel injection speed increase signal requested by the transmission control unit is received during the gear shifting phase, it is judged as the downshifting and speed-up phase.

[0109] At this time, the vehicle controller obtains the speed difference between the target gear and the actual gear through the speed ratio and the countershaft speed, and calculates the intake volume required for gear shifting and speed regulation through the pre-calibrated speed difference, clutch engagement speed and the relevant curve of the injection volume required for the transmission speed regulation.

[0110] The required air intake amount in this embodiment is calculated by subtracting the actual air intake amount calculated by the air intake pressure and air flow after the turbine to calculate the required injection amount, so as to obtain the solenoid valve opening time by looking up the table according to the gas pressure in the air storage tank and the required injection amount at this time.

[0111] In some specific embodiments, under the condition of low air pressure P≤60kpa, when the vehicle controller performs a gear shift operation, calculation and control steps are required to ensure the smoothness and power of the gear shift. Figure 3 As shown, the following is the specific implementation method:

[0112] S301: Determine the air pressure status information.

[0113] In this embodiment, the vehicle controller first detects the current air pressure value in real time through the air pressure sensor. When the air pressure value is detected to be less than or equal to 60kpa, it is determined to be in the low air pressure function available stage, and the vehicle controller will prepare to execute the corresponding low air pressure response strategy.

[0114] S302: Determine the gear shifting state.

[0115] In this embodiment, the vehicle controller receives the pre-selected gear and the actual gear information sent by the gearbox control unit. When the pre-selected gear and the actual gear are inconsistent, it is determined to be a gear shifting stage and is ready to perform a gear shifting operation.

[0116] S303: Execute downshift to increase speed.

[0117] In this embodiment, during the gear shifting process, if the engine injection speed increase signal requested by the TCU is received, it is determined to be a downshift speed increase stage. The vehicle controller is ready to increase the speed by adjusting the engine injection amount to meet the power demand after downshifting.

[0118] S304: Determine the speed difference calculation and the fuel injection amount.

[0119] In this embodiment, the speed difference between the target gear and the actual gear is obtained by the speed ratio and the countershaft speed, and the intake air volume required for the gear shifting speed regulation is calculated by using the correlation curve between the pre-calibrated speed difference, the clutch engagement speed and the injection volume required for the gearbox speed regulation.

[0120] S305: Control the operation of the solenoid valve based on the injection amount.

[0121] In this embodiment, the actual current intake volume is calculated by the intake pressure after the turbine and the intake flow sensor, and the required intake volume is subtracted from the actual intake volume to obtain the required injection volume.

[0122] Here, the opening time of the solenoid valve can be obtained by looking up the table according to the gas pressure in the gas tank and the required injection volume. The opening time of the solenoid valve is controlled so that the high-pressure gas is injected into the intake pipe according to the required amount to supplement the insufficient intake air.

[0123] S306: Execute the gear shifting process.

[0124] In this embodiment, the engine speed is increased by the combined effect of the increase in the amount of fuel injection and the supplement of the amount of jet injection. At the same time, the clutch actuator starts to work, controlling the separation and engagement process of the clutch, so that the power transmission between the engine and the gearbox gradually transitions. After the gear shift is completed, when the engine speed and the gearbox speed are synchronized, the TCU controls the gear shift mechanism to complete the gear shift operation, and the vehicle smoothly enters the new gear.

[0125] In this embodiment, after the gear shift is completed, the vehicle controller fine-tunes the power output of the engine according to the new gear position and vehicle speed information to ensure the smoothness and power of the vehicle. If an abnormality or failure occurs during the gear shift, the vehicle controller will record the relevant fault information and feedback it to the driver through the instrument panel or the vehicle information system.

[0126] In an exemplary embodiment, the gas is sprayed from the gas tank to the engine. If the gas pressure in the gas tank is sufficient to meet the needs of multiple braking, the vehicle controller controls the operation of the solenoid valve, and the high-pressure gas in the gas tank enters the engine through the intake pipe to increase the intake pressure.

[0127] Due to the increase in intake pressure, the engine's fuel injection control system is no longer restricted. The engine control unit can increase the fuel injection amount as needed to match the higher intake volume, ensure the sufficiency and efficiency of the combustion process, improve the engine's combustion efficiency and power output, and quickly increase the main box gear speed, thereby achieving the purpose of assisting in increasing the shifting speed.

[0128] In this embodiment, the method for stopping the jetting is to stop the jetting when the jetting duration is greater than or equal to the preset jetting duration, or when the rotation speed difference ΔN is less than the preset rotation speed difference threshold.

[0129] In the low-pressure working condition gear shifting auxiliary speed-up method provided by this embodiment, the required fuel injection amount can be calculated using a preset algorithm according to the downshift request instruction and the current engine speed, load, and temperature information. It ensures that the engine can provide sufficient power output during the downshift process to meet the vehicle acceleration requirements, improve fuel economy, and reduce unnecessary fuel consumption and emissions.

[0130] The method of this embodiment can provide additional intake pressure, increase the engine intake volume, and thus improve power output. Driven by the engine power, the gears inside the gearbox start to rotate and gradually reach a speed that matches the target gear. When the gearbox speed meets the gear shifting requirements, the gearbox control unit controls the shifting mechanism to complete the gear shifting operation. Ensure the smoothness and rapidity of the gear shifting process, reduce power interruption, and improve the acceleration performance and driving stability of the vehicle.

[0131] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0132] The following is an embodiment of the low-pressure working condition gear shifting assistance and acceleration system of the engine provided by the embodiment of the present disclosure. The system and the low-pressure working condition gear shifting assistance and acceleration method of the engine in the above-mentioned embodiments belong to the same inventive concept. For details not fully described in the embodiment of the low-pressure working condition gear shifting assistance and acceleration system of the engine, reference can be made to the embodiment of the low-pressure working condition gear shifting assistance and acceleration method of the above-mentioned engine.

[0133] like Figure 4 As shown, the system includes: a vehicle controller, an engine control unit, a transmission control unit, an engine, a solenoid valve, an air compressor and an air tank.

[0134] The output end of the air compressor is connected to the air inlet end of the air storage tank, and the jet end of the air storage tank is connected to the air inlet end of the engine through a solenoid valve.

[0135] The engine control unit is connected to the engine to control the engine operation and obtain the engine operation information.

[0136] The transmission control unit is connected to the transmission to control the transmission operation and obtain the transmission operation information.

[0137] The vehicle controller, engine control unit, and transmission control unit of this embodiment cooperate to control the solution, and exchange information through CAN communication to improve communication efficiency and accuracy.

[0138] Specifically, the vehicle controller determines the execution of the downshift process based on the road conditions, vehicle speed and driving intention; controls the engine and gearbox to separate and put the main box gear into neutral state.

[0139] The transmission control unit detects the downshift process and sends a downshift request command to the engine control unit.

[0140] The engine control unit calculates the required fuel injection amount based on the downshift request instruction and the current operating status information of the engine; based on the required fuel injection amount, the required injection amount and injection duration are calculated to allow the high-pressure gas to enter the cylinder through the engine intake pipe to meet the fuel injection amount requirement.

[0141] The engine executes the downshift process, driving the transmission to operate under no-load condition, so that the transmission speed reaches the shifting requirements.

[0142] In some specific embodiments, before shifting, the engine and the gearbox can be controlled to separate so that the main gearbox gear enters a neutral state, thereby avoiding damage to the transmission system caused by the power shock generated during the shifting process.

[0143] The communication and cooperation between the transmission control unit and the engine control unit ensure the synchronization and accuracy of the gear shifting process. By quickly responding to downshift request instructions, gear shift delays are reduced and system response speed is improved.

[0144] According to the downshift demand and the current state of the engine, the fuel injection amount is accurately calculated to ensure that the engine can provide sufficient power output during the downshift process. This avoids fuel waste caused by excessive or insufficient fuel injection and improves fuel economy.

[0145] By injecting high-pressure gas, the engine intake volume is increased and the combustion efficiency is improved. In addition, in a low-pressure environment, the influence of insufficient ambient air pressure on engine performance is compensated by increasing the intake volume.

[0146] As an example, the intake air volume and the actual intake air volume f(Q TFI4 ,P current ) extra Generally speaking, the calculation method is:

[0147]

[0148] f(Q TFI4 ,P current ) is the engine intake flow rate Q TFI4 and the turbine after-intake pressure P current Calculated actual air intake volume.

[0149] The gear shifting operation is performed when the engine power output and the transmission speed are synchronized to ensure the smoothness and speed of the gear shifting process. The vehicle driving stability is maintained and driving safety is improved through precise gear shifting control.

[0150] This embodiment also provides a vehicle, which can be used to implement the steps of the low-pressure working condition gear shifting auxiliary speed-up method of the engine.

[0151] Those skilled in the art will appreciate that the units and algorithm steps of each example described in the embodiment disclosed in the vehicle involved in this embodiment can be implemented by electronic hardware, computer software or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0152] In addition, the described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present invention. However, those skilled in the art will appreciate that the technical solution of the present invention can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring various aspects of the present invention.

[0153] In combination with the above-mentioned method for assisting speed-up in gear shifting under low-pressure conditions of an engine, the method for assisting speed-up in gear shifting under low-pressure conditions of an engine may be stored in a storage medium.

[0154] The storage medium stores a program product capable of implementing the above method of this specification. In some possible implementations, various aspects of the present disclosure may also be implemented in the form of a program product, which includes a program code, and when the program product is run on a terminal device, the program code is used to enable the terminal device to perform the steps according to various exemplary implementations of the present disclosure described in the above "Exemplary Method" section of this specification.

[0155] The storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0156] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for assisting speed increase by shifting gears under low pressure conditions of an engine, characterized in that: Methods include: S101: determining the downshift execution process according to the road condition, vehicle speed and driving intention; S102: Control the engine and the gearbox to separate, so that the main gearbox gear enters the neutral state; S103: The transmission control unit detects the execution of the downshift process and sends a downshift request instruction to the engine control unit; S104: The engine control unit calculates the required fuel injection amount based on the downshift request instruction and in combination with the current engine operating state information; S105: Based on the required fuel injection amount, the required injection amount and injection duration are calculated, so that the high-pressure gas enters the cylinder through the engine intake pipe to meet the fuel injection amount requirement; S106: The engine performs a downshift process to drive the transmission in an unloaded state to operate so that the transmission speed reaches the gear shifting requirement.

2. The low-pressure working condition gear shifting auxiliary speed-up method of the engine according to claim 1, characterized in that: In step S105, based on the intake air amount and the actual intake air amount f(Q TFI4 ,P current ) extra Represents the required jet volume; Difference F extra The calculation method is: f(Q TFI4 ,P current ) is the engine intake flow rate Q TFI4 and the turbine after-intake pressure P current Calculated actual air intake volume; f(ΔN,v clutch ) is the speed difference ΔN and clutch engagement speed v calculated based on the actual gear and the target gear clutch The required fuel injection quantity is obtained by looking up the table.

3. The low-pressure working condition gear shifting auxiliary speed-up method of the engine according to claim 2, characterized in that: The speed difference ΔN is calculated as: ΔN=N target -N current N target is the sleeve speed calculated from the output shaft speed and the auxiliary box speed ratio, N current Gear speed calculated for the countershaft to mainbox speed ratio.

4. The low-pressure working condition gear shifting auxiliary speed-up method of the engine according to claim 3, characterized in that: Gear speed N calculated by the speed ratio of countershaft to main gearbox current The calculation method is: Get the total speed ratio C of the gearbox bsxz ; Define the target value N of the output shaft speed after downshifting zmbz ; Based on the following calculation method, the engine speed after downshifting is N jdzs ; N jdzs =N zmbz ×C bsxz Gear speed N calculated by the speed ratio of countershaft to main gearbox current The calculation method is: N current =N fdj ×(C fzsb / C bsxz ) C fzsb is the speed ratio between the countershaft and the main gearbox; N fdj is the engine speed; C bsxz is the overall speed ratio of the gearbox.

5. The low-pressure working condition gear shifting auxiliary speed-up method of an engine according to claim 1 or 2, characterized in that: In the method, the required injection amount is calculated by subtracting the required intake amount of the engine from the actual intake amount calculated by the intake pressure and intake flow rate after the turbine, and the injection duration is obtained by looking up a table based on the gas pressure in the gas tank and the required injection amount.

6. The low-pressure working condition gear shifting auxiliary speed-up method of an engine according to claim 1 or 2, characterized in that: Step S101 also includes: When the low air pressure is less than the preset air pressure threshold, the air tank is judged to be in the low air pressure available stage; The vehicle controller receives the information of the inconsistency between the pre-selected gear and the actual gear from the gearbox control unit, and determines it as the gear shifting stage.

7. The low-pressure working condition gear shifting auxiliary speed-up method of the engine according to claim 3, characterized in that: In the method, when the jetting time is greater than or equal to a preset jetting time, or the rotation speed difference ΔN is less than a preset rotation speed difference threshold, the jetting is stopped.

8. A low-pressure gear shifting auxiliary speed-up system for an engine, characterized in that: The system is used to implement the low-pressure working condition gear shifting auxiliary speed-up method of the engine as claimed in any one of claims 1 to 7; The system includes: vehicle controller, engine control unit, transmission control unit, engine, solenoid valve, air compressor and air tank; The output end of the air compressor is connected to the air inlet end of the air storage tank, and the jet end of the air storage tank is connected to the air inlet end of the engine through a solenoid valve; The engine control unit is connected to the engine to control the engine operation and obtain the engine operation information; The gearbox control unit is connected to the gearbox to control the gearbox operation and obtain the gearbox operation information; The vehicle controller determines the downshift process based on the road conditions, vehicle speed and driving intention; controls the engine and gearbox to separate, so that the main box gear enters the neutral state; The transmission control unit detects the execution of the downshift process and sends a downshift request command to the engine control unit; The engine control unit calculates the required fuel injection amount based on the downshift request instruction and the current engine operating state information; based on the required fuel injection amount, calculates the required injection amount and injection duration, so that the high-pressure gas enters the cylinder through the engine intake pipe to meet the fuel injection amount requirement; The engine executes the downshift process, driving the transmission to operate under no-load condition, so that the transmission speed reaches the shifting requirements.

9. A vehicle, characterized in that: Steps for implementing the low-pressure working condition gear shifting auxiliary speed-up method of the engine as described in any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the low-pressure working condition gear shifting auxiliary speed-up method of the engine as claimed in any one of claims 1 to 7 are implemented.

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