Fault processing method, device and system of engine variable valve speed sensor
By acquiring and analyzing crankshaft and camshaft sensor signals and engine speed signals, the faults in the engine's variable valve timing system can be quickly diagnosed and addressed, resolving the system inaccuracy issues caused by crankshaft and camshaft sensor failures and achieving safe system operation and protection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WUXI WEIFU HIGH TECH CO LTD
- Filing Date
- 2023-10-25
- Publication Date
- 2026-07-14
AI Technical Summary
Existing technologies fail to effectively diagnose and address crankshaft camshaft sensor malfunctions in engine variable valve timing systems, leading to inaccurate system phases, potential component damage, and a lack of corresponding diagnostic and remedial methods.
By acquiring crankshaft sensor signals, camshaft sensor signals, and engine speed signals, fault diagnosis is performed to determine the severity of the fault. Based on the engine controller's instructions, appropriate fault handling methods are selected, including system shutdown or operation restriction, to protect the system from damage.
It enables rapid and accurate fault diagnosis and graded handling, ensuring that the system continues to operate in the event of minor faults and shuts down immediately in the event of serious faults to prevent system damage, and does not require modification of the engine controller, which facilitates market promotion.
Smart Images
Figure CN117345452B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of OBD technology in engine electronic control systems, and particularly to a fault handling method, a fault handling device, and a fault handling system for an engine variable valve speed sensor. Background Technology
[0002] During operation, the valve timing parameters of a traditional engine can only ensure optimal performance of the internal combustion engine under certain operating conditions. It cannot achieve variable valve phase and lift, and therefore cannot meet the current overall requirements for high engine efficiency, low fuel consumption, and low emissions.
[0003] Therefore, variable valve timing technology emerged. Variable valve timing technology can continuously adjust valve opening timing, valve opening duration, and valve lift according to changes in engine operating conditions. However, less attention is paid to the diagnosis and handling of component failures. In the variable valve timing electronic control system of an engine, the crankshaft camshaft sensor is responsible for calculating the system phase and engine speed, and is a core sensor in the system. If the crankshaft camshaft sensor malfunctions, inaccurate system phase will lead to inaccurate variable valve opening phase, posing a risk of component damage. Therefore, corresponding diagnosis and handling are necessary. Currently, most existing technologies focus on the structural design of the variable valve timing mechanism, and there are currently no methods for diagnosing and handling crankshaft camshaft sensor failures in variable valve timing electronic control systems. Summary of the Invention
[0004] This invention provides a fault handling method, a fault handling device, and a fault handling system for an engine variable valve speed sensor. After a crankshaft camshaft sensor malfunctions, the invention quickly diagnoses the relevant fault and selects the appropriate fault handling method based on engine controller instructions and the severity of the fault to prevent system damage.
[0005] As a first aspect of the present invention, a fault handling method for an engine variable valve speed sensor is provided, wherein the engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor, and the fault handling method for the engine variable valve speed sensor includes:
[0006] Step S1: Acquire crankshaft sensor signal, camshaft sensor signal, and engine speed signal;
[0007] Step S2: Diagnose the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor;
[0008] Step S3: Receive the engine stop command, and determine the fault handling mode of the engine variable valve speed sensor based on the engine stop command and the fault diagnosis information of the engine variable valve speed sensor.
[0009] Step S4: Control the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor.
[0010] Furthermore, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor also includes:
[0011] Determine if there is a battery malfunction;
[0012] If a battery fault is present, crankshaft sensor fault diagnosis is not performed; if no battery fault is present, the 5V power supply module corresponding to the crankshaft sensor is checked for faults.
[0013] If the 5V power supply module corresponding to the crankshaft sensor is faulty, no crankshaft sensor fault diagnosis is performed; if the 5V power supply module corresponding to the crankshaft sensor is not faulty, the crankshaft sensor is diagnosed as having missing teeth, extra teeth, or abnormal tooth width based on the acquired crankshaft sensor signal.
[0014] If the crankshaft sensor does not have any missing teeth, extra teeth, or abnormal tooth width faults, then no crankshaft sensor fault diagnosis is performed; if the crankshaft sensor has any missing teeth, extra teeth, or abnormal tooth width faults, then the crankshaft sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the crankshaft sensor exceeds the crankshaft sensor fault de-jittering time.
[0015] If the duration of an occasional fault does not exceed the crankshaft sensor fault de-jitter time, no crankshaft sensor fault determination is performed; if the duration of an occasional fault exceeds the crankshaft sensor fault de-jitter time, a crankshaft sensor fault is diagnosed.
[0016] Furthermore, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor also includes:
[0017] Determine if there is a battery malfunction;
[0018] If a battery fault is present, do not perform cam sensor fault diagnosis; if no battery fault is present, determine whether the 5V power supply module corresponding to the cam sensor is faulty.
[0019] If the 5V power supply module corresponding to the cam sensor is faulty, no fault judgment is made for the cam sensor; if the 5V power supply module corresponding to the cam sensor is not faulty, the cam sensor is judged to have missing teeth, extra teeth, or abnormal tooth width based on the obtained cam sensor signal.
[0020] If the cam sensor does not have any faults such as missing teeth, extra teeth, or abnormal tooth width, then no cam sensor fault judgment is performed; if the cam sensor has any faults such as missing teeth, extra teeth, or abnormal tooth width, then the cam sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the cam sensor exceeds the cam sensor fault debouncing time.
[0021] If the duration of an occasional fault does not exceed the cam sensor's fault debouncing time, no cam sensor fault determination is performed; if the duration of an occasional fault exceeds the cam sensor's fault debouncing time, a cam sensor fault is diagnosed.
[0022] Furthermore, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor also includes:
[0023] Determine if there is a fault in the engine variable valve speed sensor;
[0024] If the engine variable valve speed sensor is faulty, no fault diagnosis of unreasonable engine speed will be performed; if the engine variable valve speed sensor is not faulty, the received first engine speed value will be compared with the second engine speed value.
[0025] If the absolute value of the difference between the first engine speed value and the second engine speed value does not exceed the first difference limit, then no engine speed unreasonable fault diagnosis will be performed; if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the first difference limit, then it is determined that there is a first engine speed unreasonable fault, and it is determined whether the duration of the first engine speed unreasonable fault exceeds the first engine speed unreasonable fault de-vibration time.
[0026] If the duration of the first engine speed unreasonable fault does not exceed the first engine speed unreasonable fault de-shutdown time, then no engine speed unreasonable fault diagnosis is performed; if the duration of the first engine speed unreasonable fault exceeds the first engine speed unreasonable fault de-shutdown time, then the first engine speed unreasonable fault is diagnosed.
[0027] If the absolute value of the difference between the first engine speed value and the second engine speed value does not exceed the second difference limit, then no engine speed unreasonable fault diagnosis is performed; if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the second difference limit, then it is determined that there is a second engine speed unreasonable fault, and it is determined whether the duration of the second engine speed unreasonable fault exceeds the second engine speed unreasonable fault de-vibration time; wherein, the second difference limit is lower than the first difference limit;
[0028] If the duration of the second engine speed malfunction does not exceed the second engine speed malfunction de-shutdown time, then no engine speed malfunction diagnosis will be performed; if the duration of the second engine speed malfunction exceeds the second engine speed malfunction de-shutdown time, then the second engine speed malfunction will be diagnosed.
[0029] Furthermore, the step of receiving an engine shutdown command and determining the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor further includes:
[0030] Receives engine stop command output from engine controller. If engine stop command is 1, a fault alarm is triggered and the system enters stop mode. If engine stop command is 0, it determines whether there is a crankshaft sensor fault.
[0031] If a crankshaft sensor malfunction is detected, a fault alarm will be triggered and the system will enter shutdown mode; if no crankshaft sensor malfunction is detected, the system will determine if a camshaft sensor malfunction is detected.
[0032] If a cam sensor malfunction occurs and the first engine speed is higher than the speed threshold, a fault alarm is triggered and the system enters a shutdown mode. If a cam sensor malfunction occurs and the first engine speed is lower than the speed threshold, a fault alarm is triggered but no fault handling is performed. If there is no cam sensor malfunction, it is determined whether there is an unreasonable first engine speed malfunction.
[0033] If a fault of unreasonable first engine speed exists, a fault alarm will be triggered and the system will enter limp mode; if no fault of unreasonable first engine speed exists, it will be determined whether a fault of unreasonable second engine speed exists.
[0034] If there is an unreasonable second engine speed fault, a fault alarm will be triggered but no fault handling will be performed; if there is no unreasonable second engine speed fault, it means there is no fault and the system will not perform any handling.
[0035] Furthermore, the step of controlling the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor also includes:
[0036] When the system is in shutdown mode, the duty cycle of the IMV valve is obtained based on the duty cycle when the system is shut down, and the opening angle of the valve drive solenoid valve is set to 0°.
[0037] Once the system enters limp mode, the duty cycle of the IMV valve is obtained by referring to the system limp duty cycle curve based on the engine speed value. The opening duration of the valve drive solenoid valve is then set to the minimum value between the normal opening duration and the opening duration obtained by referring to the system limp opening duration curve based on the engine speed value.
[0038] As another aspect of the present invention, a fault handling device for an engine variable valve speed sensor is provided, for implementing the fault handling method for the engine variable valve speed sensor described above. The engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor. The fault handling device for the engine variable valve speed sensor includes:
[0039] The acquisition module is used to acquire crankshaft sensor signals, camshaft sensor signals, and engine speed signals;
[0040] The fault diagnosis module is used to diagnose the faults of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal, so as to obtain the fault diagnosis information of the engine variable valve speed sensor.
[0041] The fault handling module is used to receive the engine shutdown command and determine the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor.
[0042] The control module is used to control the corresponding actuators according to the fault handling mode of the engine variable valve speed sensor.
[0043] As another aspect of the present invention, a fault handling system for an engine variable valve speed sensor is provided, comprising: an engine controller, an engine signal disk, an engine variable valve speed sensor, a variable valve controller, an IMV valve, and a valve drive solenoid valve. The variable valve controller is connected to the engine controller, the engine variable valve speed sensor, and the IMV valve respectively. The engine variable valve speed sensor is also connected to the engine signal disk. The IMV valve is also connected to the valve drive solenoid valve. The engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor. The variable valve controller includes the fault handling device for the engine variable valve speed sensor described above.
[0044] The variable valve controller receives a first engine speed value and an engine stop command from the engine controller. The engine variable valve speed sensor outputs the crankshaft sensor signal and camshaft sensor signal based on the signal collected from the engine signal disk. The variable valve controller calculates a second engine speed value from the received crankshaft sensor signal and camshaft sensor signal. When the engine variable valve speed sensor malfunctions, the engine variable valve speed sensor fault handling device can calculate the fault handling mode of the engine variable valve speed sensor based on the engine stop command, the first engine speed value, the second engine speed value, the crankshaft sensor signal, and the camshaft sensor signal, and control the IMV valve and valve drive solenoid valve to operate to protect the safe operation of the entire engine variable valve electronic control system.
[0045] Furthermore, the variable valve controller also includes a memory for storing fault diagnosis information of the engine variable valve speed sensor.
[0046] The fault handling method for the engine variable valve speed sensor provided by the present invention has the following beneficial effects:
[0047] (1) The present invention is used for crankshaft cam sensor fault diagnosis in engine variable valve electronic control system. When the system has a corresponding fault, the fault diagnosis can be completed quickly and accurately, ensuring that the system responds quickly after the fault occurs.
[0048] (2) In this invention, the crankshaft cam sensor fault is diagnosed in the variable valve electronic control system of the engine. The system is graded according to the engine controller command and the severity of the fault. When the fault is minor, the system can continue to operate after being restricted. When the fault is severe, the system is stopped immediately to protect the system from damage.
[0049] (3) The diagnosis and handling of the corresponding faults are all completed by the variable valve controller, and the engine controller does not need to be modified, which facilitates market promotion and application. Attached Figure Description
[0050] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:
[0051] Figure 1 A flowchart of a fault handling method for an engine variable valve speed sensor provided by the present invention.
[0052] Figure 2 A flowchart for crankshaft sensor fault diagnosis provided by the present invention.
[0053] Figure 3 A flowchart for cam sensor fault diagnosis provided by the present invention.
[0054] Figure 4 The flowchart for diagnosing engine speed inappropriateness provided by the present invention is shown.
[0055] Figure 5 A flowchart for crankshaft cam sensor fault handling provided by the present invention.
[0056] Figure 6 This is a structural diagram of the fault handling device for the engine variable valve speed sensor provided by the present invention.
[0057] Figure 7 This is a structural diagram of the fault handling system for the engine variable valve speed sensor provided by the present invention. Detailed Implementation
[0058] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0059] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.
[0060] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0061] This embodiment provides a fault handling method for an engine variable valve speed sensor, which includes a crankshaft sensor and a camshaft sensor, such as... Figure 1 As shown, the fault handling method for the engine variable valve speed sensor includes:
[0062] Step S1: Acquire crankshaft sensor signal, camshaft sensor signal, and engine speed signal;
[0063] Step S2: Diagnose the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor;
[0064] Step S3: Receive the engine stop command, and determine the fault handling mode of the engine variable valve speed sensor based on the engine stop command and the fault diagnosis information of the engine variable valve speed sensor.
[0065] Step S4: Control the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor.
[0066] Preferably, such as Figure 2 As shown, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor further includes:
[0067] Determine if there is a battery malfunction;
[0068] If a battery fault is present, crankshaft sensor fault diagnosis is not performed; if no battery fault is present, the 5V power supply module corresponding to the crankshaft sensor is checked for faults.
[0069] If the 5V power supply module corresponding to the crankshaft sensor is faulty, no crankshaft sensor fault diagnosis is performed; if the 5V power supply module corresponding to the crankshaft sensor is not faulty, the crankshaft sensor is diagnosed as having missing teeth, extra teeth, or abnormal tooth width based on the acquired crankshaft sensor signal.
[0070] If the crankshaft sensor does not have any missing teeth, extra teeth, or abnormal tooth width faults, then no crankshaft sensor fault diagnosis is performed; if the crankshaft sensor has any missing teeth, extra teeth, or abnormal tooth width faults, then the crankshaft sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the crankshaft sensor exceeds the crankshaft sensor fault de-jittering time.
[0071] If the duration of an occasional fault does not exceed the crankshaft sensor fault de-jitter time, no crankshaft sensor fault determination is performed; if the duration of an occasional fault exceeds the crankshaft sensor fault de-jitter time, a crankshaft sensor fault is diagnosed.
[0072] Preferably, such as Figure 3As shown, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor further includes:
[0073] Determine if there is a battery malfunction;
[0074] If a battery fault is present, do not perform cam sensor fault diagnosis; if no battery fault is present, determine whether the 5V power supply module corresponding to the cam sensor is faulty.
[0075] If the 5V power supply module corresponding to the cam sensor is faulty, no fault judgment is made for the cam sensor; if the 5V power supply module corresponding to the cam sensor is not faulty, the cam sensor is judged to have missing teeth, extra teeth, or abnormal tooth width based on the obtained cam sensor signal.
[0076] If the cam sensor does not have any faults such as missing teeth, extra teeth, or abnormal tooth width, then no cam sensor fault judgment is performed; if the cam sensor has any faults such as missing teeth, extra teeth, or abnormal tooth width, then the cam sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the cam sensor exceeds the cam sensor fault debouncing time.
[0077] If the duration of an occasional fault does not exceed the cam sensor's fault debouncing time, no cam sensor fault determination is performed; if the duration of an occasional fault exceeds the cam sensor's fault debouncing time, a cam sensor fault is diagnosed.
[0078] Preferably, such as Figure 4 As shown, the step of diagnosing the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor further includes:
[0079] Determine if there is a fault in the engine variable valve speed sensor;
[0080] If the engine variable valve speed sensor is faulty, no fault diagnosis of unreasonable engine speed will be performed; if the engine variable valve speed sensor is not faulty, the received first engine speed value will be compared with the second engine speed value.
[0081] If the absolute value of the difference between the first engine speed value and the second engine speed value does not exceed the first difference limit, then no engine speed unreasonable fault diagnosis will be performed; if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the first difference limit, then it is determined that there is a first engine speed unreasonable fault, and it is determined whether the duration of the first engine speed unreasonable fault exceeds the first engine speed unreasonable fault de-vibration time.
[0082] If the duration of the first engine speed unreasonable fault does not exceed the first engine speed unreasonable fault de-shutdown time, then no engine speed unreasonable fault diagnosis is performed; if the duration of the first engine speed unreasonable fault exceeds the first engine speed unreasonable fault de-shutdown time, then the first engine speed unreasonable fault is diagnosed.
[0083] If the absolute value of the difference between the first engine speed value and the second engine speed value does not exceed the second difference limit, then no engine speed unreasonable fault diagnosis is performed; if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the second difference limit, then it is determined that there is a second engine speed unreasonable fault, and it is determined whether the duration of the second engine speed unreasonable fault exceeds the second engine speed unreasonable fault de-vibration time; wherein, the second difference limit is lower than the first difference limit;
[0084] If the duration of the second engine speed malfunction does not exceed the second engine speed malfunction de-shutdown time, then no engine speed malfunction diagnosis will be performed; if the duration of the second engine speed malfunction exceeds the second engine speed malfunction de-shutdown time, then the second engine speed malfunction will be diagnosed.
[0085] Preferably, such as Figure 5 As shown, the step of receiving an engine shutdown command and determining the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor further includes:
[0086] Receives engine stop command output from engine controller. If engine stop command is 1, a fault alarm is triggered and the system enters stop mode. If engine stop command is 0, it determines whether there is a crankshaft sensor fault.
[0087] If a crankshaft sensor malfunction is detected, a fault alarm will be triggered and the system will enter shutdown mode; if no crankshaft sensor malfunction is detected, the system will determine if a camshaft sensor malfunction is detected.
[0088] If a cam sensor malfunction occurs and the first engine speed is higher than the speed threshold, a fault alarm is triggered and the system enters a shutdown mode. If a cam sensor malfunction occurs and the first engine speed is lower than the speed threshold, a fault alarm is triggered but no fault handling is performed. If there is no cam sensor malfunction, it is determined whether there is an unreasonable first engine speed malfunction.
[0089] If a fault of unreasonable first engine speed exists, a fault alarm will be triggered and the system will enter limp mode; if no fault of unreasonable first engine speed exists, it will be determined whether a fault of unreasonable second engine speed exists.
[0090] If there is an unreasonable second engine speed fault, a fault alarm will be triggered but no fault handling will be performed; if there is no unreasonable second engine speed fault, it means there is no fault and the system will not perform any handling.
[0091] Preferably, the step of controlling the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor further includes:
[0092] When the system is in shutdown mode, the duty cycle of the IMV valve is obtained based on the duty cycle when the system is shut down, and the opening angle of the valve drive solenoid valve is set to 0°.
[0093] Once the system enters limp mode, the duty cycle of the IMV valve is obtained by referring to the system limp duty cycle curve based on the engine speed value. The opening duration of the valve drive solenoid valve is then set to the minimum value between the normal opening duration and the opening duration obtained by referring to the system limp opening duration curve based on the engine speed value.
[0094] The fault handling method for the variable valve speed sensor of the engine provided in this embodiment of the invention (1) is used for fault diagnosis of the crankshaft cam sensor of the variable valve electronic control system of the engine. When the corresponding fault occurs in the system, the fault diagnosis can be completed quickly and accurately, ensuring that the system responds quickly after the fault occurs; (2) when the crankshaft cam sensor fault is diagnosed in the variable valve electronic control system of the engine, the system is graded according to the engine controller instructions and the severity level of the fault. When the fault is minor, the fault can continue to run after being restricted. When the fault is severe, the engine is stopped immediately to protect the system from damage; (3) the corresponding fault diagnosis and handling are completed by the variable valve controller. The engine controller does not need to be modified, which is convenient for market promotion and application.
[0095] As another embodiment of the present invention, a fault handling device for an engine variable valve speed sensor is provided, used to implement the fault handling method for the engine variable valve speed sensor described above. The engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor, such as... Figure 6As shown, the fault handling device for the engine variable valve speed sensor includes:
[0096] The acquisition module is used to acquire crankshaft sensor signals, camshaft sensor signals, and engine speed signals;
[0097] The fault diagnosis module is used to diagnose the faults of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal, so as to obtain the fault diagnosis information of the engine variable valve speed sensor.
[0098] The fault handling module is used to receive the engine shutdown command and determine the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor.
[0099] The control module is used to control the corresponding actuators according to the fault handling mode of the engine variable valve speed sensor.
[0100] Specifically, the fault diagnosis module includes a crankshaft sensor fault diagnosis module, a camshaft sensor fault diagnosis module, and an engine speed unreasonable fault diagnosis module. The crankshaft sensor fault diagnosis module is used to diagnose crankshaft sensor faults, the camshaft sensor fault diagnosis module is used to diagnose camshaft sensor faults, and the engine speed unreasonable fault diagnosis module is used to diagnose engine speed unreasonable faults.
[0101] The working principle of the fault handling device for the engine variable valve speed sensor provided by the present invention can be referred to the description of the fault handling method for the engine variable valve speed sensor above, and will not be repeated here.
[0102] As another embodiment of the present invention, a fault handling system for an engine variable valve speed sensor is provided, such as... Figure 7 As shown, it includes: an engine controller 1, an engine signal disk 2, an engine variable valve speed sensor 3, a variable valve controller 4, an IMV valve 5, and a valve drive solenoid valve 6. The variable valve controller 4 is connected to the engine controller 1, the engine variable valve speed sensor 3, and the IMV valve 5 respectively. The engine variable valve speed sensor 3 is also connected to the engine signal disk 2. The IMV valve 5 is also connected to the valve drive solenoid valve 6. The engine variable valve speed sensor 3 includes a crankshaft sensor and a camshaft sensor. The variable valve controller 4 includes the fault handling device for the engine variable valve speed sensor described above.
[0103] The variable valve controller 4 receives a first engine speed value and an engine stop command from the engine controller 1. The engine variable valve speed sensor 3 outputs the crankshaft sensor signal and camshaft sensor signal based on the signal collected from the engine signal disk 2. The variable valve controller 4 calculates a second engine speed value from the received crankshaft sensor signal and camshaft sensor signal. When the engine variable valve speed sensor 3 malfunctions, the engine variable valve speed sensor fault handling device can calculate the fault handling mode of the engine variable valve speed sensor based on the engine stop command, the first engine speed value, the second engine speed value, the crankshaft sensor signal, and the camshaft sensor signal, and control the IMV valve 5 and the valve drive solenoid valve 6 to operate to protect the safe operation of the entire engine variable valve electronic control system.
[0104] It should be noted that the first engine speed value is the communication speed value of the engine controller 1, and the second engine speed value is the speed value calculated by the variable valve controller 4.
[0105] Preferably, the variable valve controller 4 further includes an EEPROM memory, which is used to store fault diagnosis information of the engine variable valve speed sensor to facilitate subsequent fault troubleshooting.
[0106] The working principle of the fault handling system for the engine variable valve speed sensor provided in this embodiment of the invention can be referred to the description of the fault handling method for the engine variable valve speed sensor above, and will not be repeated here.
[0107] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.
Claims
1. A fault handling method for an engine variable valve speed sensor, characterized in that, The engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor. The fault handling method for the engine variable valve speed sensor includes: Step S1: Acquire crankshaft sensor signal, camshaft sensor signal, and engine speed signal; Step S2: Diagnose the fault of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor; Step S3: Receive the engine stop command, and determine the fault handling mode of the engine variable valve speed sensor based on the engine stop command and the fault diagnosis information of the engine variable valve speed sensor. Step S4: Control the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor; The step of receiving an engine shutdown command and determining the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor further includes: Receives engine stop command output from engine controller. If engine stop command is 1, a fault alarm is triggered and the system enters stop mode. If engine stop command is 0, it determines whether there is a crankshaft sensor fault. If a crankshaft sensor malfunction is detected, a fault alarm will be triggered and the system will enter shutdown mode; if no crankshaft sensor malfunction is detected, the system will determine if a camshaft sensor malfunction is detected. If a cam sensor malfunction occurs and the first engine speed is higher than the speed threshold, a fault alarm is triggered and the system enters a shutdown mode. If a cam sensor malfunction occurs and the first engine speed is lower than the speed threshold, a fault alarm is triggered but no fault handling is performed. If there is no cam sensor malfunction, it is determined whether there is an unreasonable first engine speed malfunction. If a fault of unreasonable first engine speed exists, a fault alarm will be triggered and the system will enter limp mode; if no fault of unreasonable first engine speed exists, it will be determined whether a fault of unreasonable second engine speed exists. If there is an unreasonable second engine speed fault, a fault alarm will be triggered but no fault handling will be performed; if there is no unreasonable second engine speed fault, it means there is no fault and the system will not perform any handling. Among them, the variable valve controller receives a first engine speed value from the engine controller, and calculates a second engine speed value from the received crankshaft sensor signal and cam sensor signal; Specifically, if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the first difference limit, it is determined that there is a fault of unreasonable first engine speed; if the absolute value of the difference between the first engine speed value and the second engine speed value exceeds the second difference limit, it is determined that there is a fault of unreasonable second engine speed; wherein, the second difference limit is lower than the first difference limit.
2. The fault handling method for the engine variable valve speed sensor according to claim 1, characterized in that, The method of diagnosing the faults of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor further includes: Determine if there is a battery malfunction; If a battery fault is present, crankshaft sensor fault diagnosis is not performed; if no battery fault is present, the 5V power supply module corresponding to the crankshaft sensor is checked for faults. If the 5V power supply module corresponding to the crankshaft sensor is faulty, no crankshaft sensor fault diagnosis is performed; if the 5V power supply module corresponding to the crankshaft sensor is not faulty, the crankshaft sensor is diagnosed as having missing teeth, extra teeth, or abnormal tooth width based on the acquired crankshaft sensor signal. If the crankshaft sensor does not have any missing teeth, extra teeth, or abnormal tooth width faults, then no crankshaft sensor fault diagnosis is performed; if the crankshaft sensor has any missing teeth, extra teeth, or abnormal tooth width faults, then the crankshaft sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the crankshaft sensor exceeds the crankshaft sensor fault de-jittering time. If the duration of an occasional fault does not exceed the crankshaft sensor fault de-jitter time, no crankshaft sensor fault determination is performed; if the duration of an occasional fault exceeds the crankshaft sensor fault de-jitter time, a crankshaft sensor fault is diagnosed.
3. The fault handling method for the engine variable valve speed sensor according to claim 1, characterized in that, The method of diagnosing the faults of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal, and engine speed signal to obtain fault diagnosis information of the engine variable valve speed sensor further includes: Determine if there is a battery malfunction; If a battery fault is present, do not perform cam sensor fault diagnosis; if no battery fault is present, determine whether the 5V power supply module corresponding to the cam sensor is faulty. If the 5V power supply module corresponding to the cam sensor is faulty, no fault judgment is made for the cam sensor; if the 5V power supply module corresponding to the cam sensor is not faulty, the cam sensor is judged to have missing teeth, extra teeth, or abnormal tooth width based on the obtained cam sensor signal. If the cam sensor does not have any faults such as missing teeth, extra teeth, or abnormal tooth width, then no fault judgment is made for the cam sensor; if the cam sensor has any faults such as missing teeth, extra teeth, or abnormal tooth width, then the cam sensor has an occasional fault, and it is determined whether the duration of the occasional fault of the cam sensor exceeds the cam sensor fault debouncing time. If the duration of an occasional fault does not exceed the cam sensor's fault debouncing time, no cam sensor fault determination is performed; if the duration of an occasional fault exceeds the cam sensor's fault debouncing time, a cam sensor fault is diagnosed.
4. The fault handling method for the engine variable valve speed sensor according to claim 1, characterized in that, The step of controlling the corresponding actuator according to the fault handling mode of the engine variable valve speed sensor also includes: When the system is in shutdown mode, the duty cycle of the IMV valve is obtained based on the duty cycle when the system is shut down, and the opening angle of the valve drive solenoid valve is set to 0°. Once the system enters limp mode, the duty cycle of the IMV valve is obtained by referring to the system limp duty cycle curve based on the engine speed value. The opening duration of the valve drive solenoid valve is then set to the minimum value between the normal opening duration and the opening duration obtained by referring to the system limp opening duration curve based on the engine speed value.
5. A fault handling device for an engine variable valve speed sensor, used to implement the fault handling method for an engine variable valve speed sensor according to any one of claims 1 to 4, wherein the engine variable valve speed sensor includes a crankshaft sensor and a camshaft sensor, and the fault handling device for the engine variable valve speed sensor includes: The acquisition module is used to acquire crankshaft sensor signals, camshaft sensor signals, and engine speed signals; The fault diagnosis module is used to diagnose the faults of the engine variable valve speed sensor based on the crankshaft sensor signal, camshaft sensor signal and engine speed signal, so as to obtain the fault diagnosis information of the engine variable valve speed sensor. The fault handling module is used to receive the engine shutdown command and determine the fault handling mode of the engine variable valve speed sensor based on the engine shutdown command and the fault diagnosis information of the engine variable valve speed sensor. The control module is used to control the corresponding actuators according to the fault handling mode of the engine variable valve speed sensor.
6. A fault handling system for an engine variable valve speed sensor, characterized in that, include: The engine controller (1), engine signal disk (2), engine variable valve speed sensor (3), variable valve controller (4), IMV valve (5) and valve drive solenoid valve (6) are respectively connected to the engine controller (1), engine variable valve speed sensor (3) and IMV valve (5). The engine variable valve speed sensor (3) is also connected to the engine signal disk (2). The IMV valve (5) is also connected to the valve drive solenoid valve (6). The engine variable valve speed sensor (3) includes a crankshaft sensor and a camshaft sensor. The variable valve controller (4) includes the fault handling device for the engine variable valve speed sensor as described in claim 5. The variable valve controller (4) receives the first engine speed value and engine stop command from the engine controller (1). The engine variable valve speed sensor (3) outputs the crankshaft sensor signal and cam sensor signal based on the signal collected from the engine signal disk (2). The variable valve controller (4) calculates the second engine speed value based on the received crankshaft sensor signal and cam sensor signal. When the engine variable valve speed sensor (3) malfunctions, the engine variable valve speed sensor fault handling device can calculate the fault handling mode of the engine variable valve speed sensor based on the engine stop command, the first engine speed value, the second engine speed value, the crankshaft sensor signal and the cam sensor signal, and control the IMV valve (5) and the valve drive solenoid valve (6) to operate to protect the safe operation of the entire engine variable valve electronic control system.
7. The fault handling system for the engine variable valve speed sensor according to claim 6, characterized in that, The variable valve controller (4) also includes a memory for storing fault diagnosis information of the engine variable valve speed sensor.