Hybrid gearbox fault handling gear control method based on mode input

Abstract

The invention relates to gearbox fault processing, in particular to a hybrid gearbox fault processing gear control method based on mode input. The problems that an existing AMT control system cannot achieve gearbox fault handling gear control when a P2-configuration hybrid vehicle is in different modes and all the modes are switched are solved, and faults encountered when the whole vehicle is in the different modes are classified; firstly, the vehicle operation modes comprise the four modes that the whole vehicle is static and is not in the gear shifting process in the pure electric mode, the whole vehicle is not static and is not in the neutral gear in the pure electric mode, the whole vehicle is static and is not in the gear shifting process in the hybrid mode, and the whole vehicle is not static and is not in the neutral gear in the hybrid mode. Faults of forcibly returning to the neutral gear and forbidding gear shifting exist in the hybrid mode, faults of forcibly returning to the neutral gear and forbidding gear shifting also exist in the pure electric mode, and correct gear decisions of the vehicle can be made under the fault conditions of different modes through condition judgment.

Description

Technical Field

[0001] The present invention relates to a gearbox fault processing method, and in particular to a hybrid gearbox fault processing gear control method based on mode input. Background Art

[0002] As a green transportation tool that is both economical and powerful, hybrid vehicles have shown unparalleled advantages and competitiveness in the fierce competition in the commercial vehicle market. However, in order to further improve the operating stability and risk response capabilities of hybrid vehicles, it is necessary to further optimize the hybrid transmission fault handling method and improve the stability of the hybrid AMT transmission and the safety of the entire vehicle.

[0003] At present, the AMT transmission of traditional fuel vehicles uses the engine as the power source when handling faults, while pure electric vehicles use the motor as the power source. Vehicles with different power sources have different control response methods when handling faults. Compared with the structural type of pure fuel vehicles and pure electric vehicles with only a single power source, hybrid vehicles have two sets of power sources. Most existing hybrid vehicles usually follow the way of pure fuel vehicles and pure electric vehicles when solving transmission faults, using a "one-size-fits-all" mode. No matter which mode they are in, they must stop and turn off the power source to handle faults. The biggest difference between hybrid vehicle transmission fault handling and pure fuel AMT transmission and pure electric vehicles is that it has two sets of power units, and the fault handling modes of the two sets of power units are not the same. The most special thing is that it has mode switching, especially for P2 configuration hybrid vehicles with the motor located at the input end of the transmission. How to handle transmission faults in different modes and when switching between modes has become a technical problem.

[0004] The Chinese invention patent with the authorization announcement number CN104950776B discloses a parallel hybrid AMT control system, including a drive layer and an application layer; wherein the drive layer includes a CAN communication module, a basic module and a fault handling module; the CAN communication module is used to complete the communication protocol stack based on CAN2.0B, CCP and UDS protocols; the basic module is used to complete the basic algorithm library, motor control and protection and clutch control and protection; the fault handling module is used to complete the fault analysis and fault handling functions; the application layer is responsible for implementing various functions at the system business logic level, including a signal processing module and an application function module. Compared with the traditional AMT control system, the parallel hybrid AMT control system provided by the above invention introduces HCU, motor, battery and its control system, etc. The TCU will coordinate with the HCU to control the entire power and transmission system to improve the control reliability of the overall system, but the control system still fails to properly solve the problem of gearbox fault handling and gear control of P2-configured hybrid vehicles in different modes and when switching modes. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problem that the existing AMT control system fails to solve the transmission fault handling gear control of a P2 configuration hybrid vehicle in different modes and when switching between modes, and to provide a hybrid transmission fault handling gear control method based on mode input.

[0006] In order to achieve the above-mentioned invention object, the present invention provides the following technical solutions:

[0007] A hybrid transmission fault handling gear control method based on mode input is special in that it includes the following steps:

[0008] S1, determine whether the vehicle is in a stationary state, if so, execute step S2, if not, execute step S8;

[0009] S2, determining whether the vehicle is in the process of shifting gears, if so, returning to step S1, if not, executing step S3;

[0010] S3, determining whether the vehicle is in pure electric mode, if so, executing step S4, if not, executing step S5;

[0011] S4, determining whether the vehicle triggers a pure electric forced return to neutral fault, if so, executing step S6, if not, returning to step S1;

[0012] S5, determining whether the vehicle triggers a hybrid forced return to neutral fault, if so, executing step S6, if not, returning to step S1;

[0013] S6, the gearbox returns to neutral gear, and controls the vehicle to return to neutral gear forcibly;

[0014] S7, confirm whether the vehicle is back to neutral, if so, return to step S1, if not, return to step S6;

[0015] S8, determine whether the vehicle is in neutral, if so, return to step S1, if not, execute step S9;

[0016] S9, determining whether the vehicle is in pure electric mode, if so, executing step S10, if not, executing step 11;

[0017] S10, determining whether the vehicle triggers a pure electric gear shift prohibition fault, if so, executing step S12, if not, returning to step S1;

[0018] S11, determining whether the vehicle triggers a hybrid gear shift prohibition fault, if so, executing step S12, if not, returning to step S1;

[0019] S12: The gearbox prohibits the gear shifting operation, forcing the vehicle to maintain the current gear position;

[0020] S13, confirm whether the vehicle responds to the prohibition of gear shifting, if not, return to execute step S12; if so, stop the vehicle by braking and wait for maintenance; after the processing is completed, put the vehicle into the forward gear, and then return to step S1 to complete a hybrid transmission fault processing gear control based on the mode input.

[0021] Furthermore, step S1 is specifically as follows: the TCU receives the operation status signal through the CAN bus to determine whether the vehicle is in a stationary state. If so, step S2 is executed; if not, step S8 is executed.

[0022] Further, step S2 is specifically as follows: the TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in the gear shifting process, if so, return to step S1, if not, execute step S3;

[0023] Step S8 is specifically as follows: TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in neutral. If so, it returns to step S1; if not, it executes step S9.

[0024] Further, step S3 is specifically: TCU receives the vehicle mode signal through the CAN bus, determines whether the vehicle is in the pure electric mode, if so, executes step S4, if not, executes step S5;

[0025] Step S9 is specifically as follows: TCU receives the vehicle mode signal through the CAN bus to determine whether the vehicle is in pure electric mode. If so, step S10 is executed; if not, step S11 is executed.

[0026] Further, step S4 is specifically as follows: TCU receives a fault signal through the CAN bus, and determines whether the vehicle triggers a pure electric forced return to neutral fault. If so, step S6 is executed; if not, step S1 is returned;

[0027] Step S10 is specifically as follows: TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a pure electric gear shifting prohibition fault. If so, execute step S12; if not, return to step S1.

[0028] Further, step S5 is specifically: TCU receives the fault signal through the CAN bus, and determines whether the vehicle triggers the hybrid forced return to neutral fault. If so, step S6 is executed, if not, the process returns to step S1;

[0029] Step S11 is specifically as follows: TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a hybrid gear shifting prohibition fault. If so, step S12 is executed; if not, the process returns to step S1.

[0030] Further, step S6 is specifically as follows: the TCU sends a command to the gearbox via the CAN bus to force the target gear to be neutral, and the gearbox controls the shift actuator and the clutch actuator to return to neutral, thereby controlling the vehicle to return to neutral;

[0031] Step S12 is specifically as follows: the TCU sends a gear shift prohibition instruction to the gearbox through the CAN bus, and the gearbox prohibits the gear shift operation by controlling the gear shift actuator and the clutch actuator, forcing the entire vehicle to maintain the current gear.

[0032] Further, step S7 is specifically as follows: TCU receives instrument and gear position signal feedback via CAN bus to confirm whether the vehicle is back to neutral gear, if so, returns to step S1, if not, returns to step S6;

[0033] Step S13 is specifically as follows: TCU receives instrument and gear signal feedback through the CAN bus to confirm whether the vehicle responds to the gear shifting prohibition. If not, it returns to execute step S12; if so, the vehicle is stopped by braking and waits for maintenance. After the processing is completed, the vehicle is shifted into the forward gear and returns to step S1 to complete a hybrid transmission fault processing gear control based on the mode input.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The present invention provides a hybrid transmission fault processing gear control method based on mode input, which classifies the faults encountered by the whole vehicle in different modes. First, the vehicle operation mode includes four modes: the whole vehicle is stationary and not in the gear shifting process in the pure electric mode, the whole vehicle is not stationary and not in neutral in the pure electric mode, the whole vehicle is stationary and not in the gear shifting process in the hybrid mode, and the whole vehicle is not stationary and not in neutral in the hybrid mode. In addition, there are faults that trigger forced return to neutral and prohibit gear shifting in the hybrid mode, and there are faults that trigger forced return to neutral and prohibit gear shifting in the pure electric mode. Through conditional judgment, the fault conditions of the vehicle in different modes are determined. The correct gear decision can be made under certain conditions. If the hybrid vehicle is in pure electric mode, since the power source comes from the motor at this time, when a related engine failure occurs, it can still shift gears and drive normally; if it is in hybrid mode at this time, it must enter a specific gear restriction mode according to the fault to ensure driving safety. This method provides certain theoretical guidance and technical support for how hybrid vehicles with P2 configuration can complete gear restriction according to the vehicle status and faults in different modes, especially when dealing with faults in the process of mode switching, such as pure electric-hybrid or hybrid-pure electric. It has good reference and guiding significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a flow chart of an embodiment of a hybrid transmission fault handling gear control method based on mode input according to the present invention;

[0037] Figure 2 This is an architecture diagram of a gearbox fault processing gear control system designed to implement the hybrid gearbox fault processing gear control method based on mode input in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with the accompanying drawings and exemplary embodiments.

[0039] Reference Figure 2 It can be seen from the architecture diagram of the gear control system for gear fault handling that in this system, the main input signals include vehicle mode signals (including pure electric mode and hybrid mode), operating status signals, fault signals (including speed fault, air pressure fault, engine fault, clutch fault, partial message loss and bus signal fault, etc.), gear signals, clutch status signals, engine ECU (electronic control unit) signals, handle signals and instrument signals, etc. HCU (hybrid control unit) and TCU (transmission control unit) interact with these signals through the CAN bus. TCU can control the target gear control in different modes and different vehicle operating states in combination with the fault handling program, change the gear by controlling the gear actuator and clutch actuator of the gearbox, realize the function of prohibiting gear shifting or forcing back to neutral in the fault state, and feedback to the vehicle and instrument through the CAN bus.

[0040] The biggest difference between hybrid vehicle transmission fault handling and pure fuel AMT transmission and pure electric vehicle lies in the gear selection control. The present invention mainly optimizes this part. If the TCU receives a fault signal during the use of the vehicle, the hybrid transmission fault handling gear control method based on mode input provided by the present invention is used to handle the fault, and the vehicle is controlled to complete the correct gear selection, clutch control and other transmission functions under the fault state.

[0041] The present invention provides a hybrid transmission fault handling gear control method based on mode input, and its flow chart is as follows: Figure 1 As shown, the following steps are included:

[0042] S1, TCU receives the running status signal through the CAN bus to determine whether the vehicle is in a stationary state. If so, execute step S2, if not, execute step S8;

[0043] S2, TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in the gear shifting process, if so, return to step S1, if not, execute step S3;

[0044] S3, TCU receives the vehicle mode signal through the CAN bus, and determines whether the vehicle is in pure electric mode. If so, execute step S4, if not, execute step S5;

[0045] S4, TCU receives the fault signal through the CAN bus, and determines whether the vehicle triggers the pure electric forced return to neutral fault. If so, execute step S6, if not, return to step S1;

[0046] S5, TCU receives the fault signal through the CAN bus, and determines whether the vehicle triggers the hybrid forced return to neutral fault. If so, execute step S6, if not, return to step S1;

[0047] S6, TCU sends a command to the gearbox through the CAN bus to force the target gear to be neutral. The gearbox controls the shift actuator and the clutch actuator to return to neutral, and controls the vehicle to return to neutral.

[0048] S7, TCU receives instrument and gear position signal feedback via CAN bus to confirm whether the vehicle is back to neutral gear, if yes, return to step S1, if no, return to step S6;

[0049] S8, TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in neutral, if so, return to step S1, if not, execute step S9;

[0050] S9, TCU receives the vehicle mode signal through the CAN bus, and determines whether the vehicle is in the pure electric mode. If so, execute step S10, if not, execute step 11;

[0051] S10, TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a pure electric gear shift prohibition fault. If so, execute step S12; if not, return to step S1;

[0052] S11, TCU receives a fault signal through the CAN bus, and determines whether the vehicle triggers a hybrid gear shift prohibition fault. If so, execute step S12, if not, return to step S1;

[0053] S12, TCU sends a shift prohibition command to the gearbox through the CAN bus, and the gearbox prohibits the shift operation by controlling the shift actuator and the clutch actuator, forcing the vehicle to maintain the current gear position;

[0054] S13, TCU receives instrument and gear signal feedback through CAN bus to confirm whether the vehicle responds to the gear shifting prohibition. If not, it returns to execute step S12; if so, the vehicle is stopped by braking and waits for maintenance. After the processing is completed, the vehicle is put into the forward gear and returns to step S1 to complete a hybrid transmission fault processing gear control based on mode input.

[0055] In specific applications, when the input is pure electric mode and the vehicle is not stationary and the gear is not neutral, if the TCU receives any fault signal from the speed fault, low air pressure fault, clutch open fault, CAN bus signal loss fault and K30 low voltage fault, the program in the TCU will determine that the vehicle has entered a specific fault mode and meets the gear shift prohibition condition. In this state, the TCU will force the vehicle to maintain the current gear, and the entire process will not shift up or down until the vehicle stops, then exit this state and engage the starting gear. The vehicle power comes from the motor throughout the process. If none of the above faults are triggered during this process, the gear shift prohibition fault state will be exited in time, and the vehicle will respond to the normal pure electric gear shifting position.

[0056] Also in pure electric mode, when the vehicle is stationary (has been stationary or is currently stationary) and is not in the process of shifting gears, if the TCU receives any of the following faults: clutch opening fault, CAN bus signal loss fault, K30 low voltage fault, and TC1 message (handle message) loss fault, the program in the TCU determines that the vehicle has entered a specific fault mode and meets the conditions for forced return to neutral. In this state, the TCU forces the current gear to remain in neutral, and will not respond to other normal process gear inputs. Only when the above faults are not triggered will it determine to exit the forced return to neutral fault mode, and respond to the normal gear shifting process gear.

[0057] When the input is hybrid mode, the TCU determines whether the vehicle has entered a specific fault mode by receiving vehicle status signals and fault signals, just like the pure electric mode mentioned above. However, the hybrid mode mainly comes from the engine, and compared to the pure electric mode, it has additional modules such as the engine and clutch, so the hybrid mode triggers more fault conditions when entering the above two specific fault modes.

[0058] Shifting prohibited fault mode in hybrid mode: Compared with the pure electric state, several new fault signals are added, including engine start-stop fault, clutch displacement sensor fault, engine actual speed fault, clutch closing fault and EEC1 message (engine message) loss fault. These faults plus several faults in pure electric mode will trigger the specific shifting prohibited fault mode in hybrid mode when triggered at will. Its functional utility and exit conditions are the same as those in pure electric mode.

[0059] Forced return to neutral gear fault mode in hybrid mode: Similarly, several new fault signals are added compared to the pure electric state, which are similar to the prohibited shifting conditions, including engine start-stop fault, engine actual speed fault, clutch closing fault and EEC1 message loss fault. The triggering method, functional utility and exit conditions are also the same as those in the pure electric mode.

[0060] The embodiments described above are merely descriptions of specific implementation methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A hybrid transmission fault handling gear control method based on mode input, characterized in that: The following steps are involved: S1, determine whether the vehicle is in a stationary state, if so, execute step S2, if not, execute step S8; S2, determining whether the vehicle is in the process of shifting gears, if so, returning to step S1, if not, executing step S3; S3, determining whether the vehicle is in pure electric mode, if so, executing step S4, if not, executing step S5; S4, determining whether the vehicle triggers a pure electric forced return to neutral fault, if so, executing step S6, if not, returning to step S1; S5, determining whether the vehicle triggers a hybrid forced return to neutral fault, if so, executing step S6, if not, returning to step S1; S6, the gearbox returns to neutral gear, and controls the vehicle to return to neutral gear forcibly; S7, confirm whether the vehicle is back to neutral, if so, return to step S1, if not, return to step S6; S8, determine whether the vehicle is in neutral, if so, return to step S1, if not, execute step S9; S9, determining whether the vehicle is in pure electric mode, if so, executing step S10, if not, executing step 11; S10, determining whether the vehicle triggers a pure electric gear shift prohibition fault, if so, executing step S12, if not, returning to step S1; S11, determining whether the vehicle triggers a hybrid gear shift prohibition fault, if so, executing step S12, if not, returning to step S1; S12: The gearbox prohibits the gear shifting operation, forcing the vehicle to maintain the current gear position; S13, confirm whether the vehicle responds to the prohibition of shifting, if not, return to step S12; If so, the vehicle is stopped by braking and waits for maintenance. After the maintenance is completed, the vehicle is put into the forward gear and returns to step S1 to complete a hybrid transmission fault handling gear control based on the mode input.

2. The hybrid transmission fault handling gear control method based on mode input according to claim 1, characterized in that: Step S1 is specifically as follows: TCU receives the running status signal through the CAN bus to determine whether the vehicle is in a stationary state. If so, step S2 is executed; if not, step S8 is executed.

3. The hybrid transmission fault handling gear control method based on mode input according to claim 2 is characterized in that: Step S2 specifically includes: the TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in the gear shifting process, if so, returning to step S1, if not, executing step S3; Step S8 is specifically as follows: TCU receives the gear position signal through the CAN bus to determine whether the vehicle is in neutral. If so, it returns to step S1; if not, it executes step S9.

4. The hybrid transmission fault handling gear control method based on mode input according to claim 3 is characterized in that: Step S3 is specifically: TCU receives the vehicle mode signal through the CAN bus, and determines whether the vehicle is in the pure electric mode. If so, step S4 is executed; if not, step S5 is executed; Step S9 is specifically as follows: TCU receives the vehicle mode signal through the CAN bus to determine whether the vehicle is in pure electric mode. If so, step S10 is executed; if not, step S11 is executed.

5. The hybrid transmission fault handling gear control method based on mode input according to claim 4, characterized in that: Step S4 is specifically as follows: the TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a pure electric forced return to neutral fault. If so, step S6 is executed; if not, the process returns to step S1; Step S10 is specifically as follows: TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a pure electric gear shifting prohibition fault. If so, execute step S12; if not, return to step S1.

6. The hybrid transmission fault handling gear control method based on mode input according to claim 5, characterized in that: Step S5 is specifically: TCU receives the fault signal through the CAN bus, and determines whether the vehicle triggers the hybrid forced return to neutral fault. If so, execute step S6, if not, return to step S1; Step S11 is specifically as follows: TCU receives a fault signal through the CAN bus and determines whether the vehicle triggers a hybrid gear shifting prohibition fault. If so, step S12 is executed; if not, the process returns to step S1.

7. The hybrid transmission fault handling gear control method based on mode input according to claim 6, characterized in that: Step S6 is specifically as follows: the TCU sends a command to the gearbox via the CAN bus to force the target gear to be in neutral, and the gearbox controls the shift actuator and the clutch actuator to return to neutral, thereby controlling the vehicle to return to neutral; Step S12 is specifically as follows: the TCU sends a gear shift prohibition instruction to the gearbox through the CAN bus, and the gearbox prohibits the gear shift operation by controlling the gear shift actuator and the clutch actuator, forcing the entire vehicle to maintain the current gear.

8. The hybrid transmission fault handling gear control method based on mode input according to claim 7, characterized in that: Step S7 specifically includes: TCU receives instrument and gear position signal feedback via CAN bus to confirm whether the vehicle is back to neutral gear, if yes, returns to step S1, if no, returns to step S6; Step S13 specifically includes: the TCU receives the instrument and gear position signal feedback via the CAN bus to confirm whether the vehicle responds to the gear shift prohibition, if not, returning to step S12; If so, the vehicle is stopped by braking and waits for maintenance. After the maintenance is completed, the vehicle is put into the forward gear and returns to step S1 to complete a hybrid transmission fault handling gear control based on the mode input.

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