CN-122009223-A - Method and system for protecting engine fire of plug-in hybrid electric vehicle and vehicle

CN122009223ACN 122009223 ACN122009223 ACN 122009223ACN-122009223-A

Abstract

The application provides a plug-in type hybrid electric vehicle engine fire protection method, which belongs to the technical field of hybrid electric vehicle control, wherein an engine management system is used for rapidly and accurately carrying out fault diagnosis, fault signals are transmitted to a hybrid electric vehicle controller and an instrument control module after faults are diagnosed, so that the hybrid electric vehicle controller executes corresponding fault protection control strategies according to the fault signals, the engine and other hardware of a vehicle are protected from being damaged after the engine is in fire, the instrument control module can also control fault lamp display according to the fault signals, thereby prompting a driver in time, and realizing the fire protection of the hybrid electric vehicle engine rapidly and accurately by utilizing the cooperative interaction among the engine management system, the hybrid electric vehicle controller and the instrument control module in view of combination, and improving the safety and reliability of the hybrid electric vehicle.

Inventors

MA YULIN
FU CHAO
ZHANG ZHUO
MA TAO
WANG LEI

Assignees

奇瑞汽车股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260326

Claims (10)

1. A method for protecting engine misfire of plug-in hybrid electric vehicle, the method comprising: the engine management system performs fault diagnosis in real time and transmits fault signals to the hybrid power vehicle controller and the instrument control module; after receiving the fault signal, the hybrid vehicle controller executes a corresponding fault protection control strategy; And the instrument control module controls the display of the fault lamp according to the fault signal after receiving the fault signal.
2. The method of claim 1, wherein the engine management system performs fault diagnosis in real time and transmits fault signals to the hybrid vehicle controller and the instrument control module comprises: When the engine management system confirms that the engine works in a series mode, judging whether a diagnosis precondition is met or not; when the engine management system judges that the diagnosis pre-condition is met, the engine management system enters a misfire diagnosis mode; when the engine management system enters the misfire diagnosis mode, acquiring motor torque of an integrated start power generation motor, and calculating real-time engine torque according to the motor torque; The engine management system divides the real-time engine torque by a prestored theoretical engine torque to obtain a torque achievement rate; and when the torque achievement rate is smaller than a preset achievement rate and lasts for a first preset time, the engine management system judges that the engine is in fire, and transmits the fault signal to the hybrid vehicle controller and the instrument control module.
3. The plug-in hybrid vehicle engine misfire protection method of claim 1, wherein the engine management system determines that the diagnostic precondition is satisfied when both of the following conditions are satisfied: The engine torque is greater than 20Nm, the number of broken cylinders controlled by the engine management system is less than or equal to 2, the engine speed is within the range of 700-6500rpm, the plug-in hybrid electric vehicle is not in a offline pre-exhaust stage, the delay time after the engine is started meets the preset condition, no air inlet temperature related faults and manifold pressure related faults exist, and the motor torque and driving mode signals are all effective.
4. The plug-in hybrid vehicle engine misfire protection method of claim 1, wherein the engine management system performs a fault diagnosis in real time and transmits a fault signal to a hybrid vehicle controller and an instrument control module further comprising: When the engine management system confirms that the engine works in a series mode, judging whether a diagnosis precondition is met or not; when the engine management system judges that the diagnosis pre-condition is met, the engine management system enters a misfire diagnosis mode; When the engine management system enters the misfire diagnosis mode, judging whether an oxygen heating circuit and an ignition coil share a fuse; detecting a fault condition of the ignition coil when the engine management system determines that the oxygen heating circuit and the ignition coil share a fuse; When the engine management system detects that the number of the ignition coils, of which the fault states indicate faults, of the ignition coils is larger than a preset number and lasts for a second preset time, the engine management system judges that an engine is in fire, and transmits fault signals to the hybrid vehicle controller and the instrument control module.
5. The method of claim 4, wherein the engine management system performs fault diagnosis in real time and transmits fault signals to the hybrid vehicle controller and the meter control module further comprises: Detecting a fault state of the oxygen heating circuit when the engine management system judges that the oxygen heating circuit and the ignition coil do not share a fuse; When the engine management system detects that the fault state of the oxygen heating circuit indicates that both the front oxygen sensor heating circuit and the rear oxygen sensor heating circuit are faulty and the third preset time is continued, the engine management system judges that the engine is in fire and transmits the fault signals to the hybrid vehicle controller and the instrument control module.
6. The plug-in hybrid vehicle engine misfire protection method according to any one of claims 2-5, wherein the hybrid vehicle controller executing a corresponding failsafe control strategy after receiving the failure signal comprises: And after receiving the fault signal, the hybrid vehicle controller controls the engine to stop oil injection and reduce the rotating speed.
7. The utility model provides a plug-in hybrid vehicle engine fire protection system which characterized in that, the system includes engine management system, hybrid vehicle control unit and instrument control module, wherein: The engine management system is configured to perform fault diagnosis in real time and transmit fault signals to the hybrid vehicle controller and the instrument control module; the hybrid power vehicle controller is configured to execute a corresponding fault protection control strategy after receiving the fault signal; the meter control module is configured to control a fault light display according to the fault signal after receiving the fault signal.
8. The plug-in hybrid vehicle engine misfire protection system of claim 7, wherein the engine management system is configured to: Judging whether the diagnosis precondition is satisfied when the engine is confirmed to operate in the series mode; when judging that the diagnosis precondition is satisfied, entering a misfire diagnosis mode; when the fire diagnosis mode is entered, acquiring motor torque of an integrated start power generation motor, and calculating real-time engine torque according to the motor torque; dividing the real-time engine torque by the theoretical engine torque to obtain a torque achievement rate; and when the torque achievement rate is smaller than a preset achievement rate and lasts for a first preset time, judging that the engine is in fire, and transmitting the fault signal to the hybrid vehicle controller.
9. The plug-in hybrid vehicle engine misfire protection system of claim 7, wherein the engine management system determines that the diagnostic precondition is satisfied when both of the following conditions are satisfied: The engine torque is greater than 20Nm, the number of broken cylinders controlled by the engine management system is less than or equal to 2, the engine speed is within the range of 700-6500rpm, the plug-in hybrid electric vehicle is not in a offline pre-exhaust stage, the delay time after the engine is started meets the preset condition, no air inlet temperature related faults and manifold pressure related faults exist, and the motor torque and driving mode signals are all effective.
10. A vehicle comprising a plug-in hybrid vehicle engine misfire protection system according to any of claims 7-9.

Description

Method and system for protecting engine fire of plug-in hybrid electric vehicle and vehicle Technical Field The application relates to the technical field of hybrid electric vehicle control, in particular to a plug-in type hybrid electric vehicle engine misfire protection method, system and vehicle. Background With the popularity of hybrid vehicles, the power system complexity of PHEVs (plug-in hybrid vehicles) has increased significantly. In the series mode, the engine generates power through an ISG motor (INTEGRATED STARTER Generator, integrated start Generator) to charge a battery or directly drive the motor, and the stability of the working state of the engine directly influences the performance and safety of the whole vehicle. The engine fire is a common fault type, namely that the combustible mixture in an engine cylinder cannot be normally ignited or is insufficiently combusted, and the traditional fuel-air vehicle mainly carries out fire diagnosis through crankshaft rotation speed fluctuation. However, in PHEV vehicles, there are significant limitations to conventional misfire diagnostic methods due to the intervention of ISG motors. Disclosure of Invention In view of the above, the application provides a plug-in type hybrid electric vehicle engine misfire protection method, which can realize the engine misfire protection more rapidly and accurately. In one aspect, the application provides a method for protecting engine misfire of plug-in hybrid electric vehicle, comprising the following steps: The engine management system performs fault diagnosis in real time and transmits fault signals to the hybrid power vehicle controller and the instrument control module. And after receiving the fault signal, the hybrid vehicle controller executes a corresponding fault protection control strategy. And after receiving the fault signal, the instrument control module controls the fault lamp to display according to the fault signal. Optionally, the engine management system performs fault diagnosis in real time, and transmitting the fault signal to the hybrid vehicle controller and the instrument control module includes: when the engine management system confirms that the engine is operating in the series mode, it is determined whether the diagnostic preconditions are satisfied. When the engine management system determines that the diagnosis precondition is satisfied, the engine management system enters a misfire diagnosis mode. When the engine management system enters a misfire diagnosis mode, motor torque of the integrated start power generation motor is obtained, and real-time engine torque is calculated according to the motor torque. The engine management system divides the real-time engine torque by the prestored theoretical engine torque to obtain a torque achievement rate. When the torque achievement rate is smaller than the preset achievement rate and lasts for a first preset time, the engine management system judges that the engine is in fire, and transmits fault signals to the hybrid vehicle controller and the instrument control module. Alternatively, the engine management system determines that the diagnostic preconditions are satisfied when both of the following conditions are satisfied: The engine torque is greater than 20Nm, the number of broken cylinders controlled by an engine management system is less than or equal to 2, the engine speed is within the range of 700-6500rpm, the plug-in hybrid electric vehicle is not in a offline pre-exhaust stage, the delay time after the engine is started meets the preset condition, no air inlet temperature related faults and manifold pressure related faults exist, and the motor torque and driving mode signals are all effective. Optionally, the engine management system performs fault diagnosis in real time, and transmitting fault signals to the hybrid vehicle controller and the instrument control module further includes: when the engine management system confirms that the engine is operating in the series mode, it is determined whether the diagnostic preconditions are satisfied. When the engine management system determines that the diagnosis precondition is satisfied, the engine management system enters a misfire diagnosis mode. When the engine management system enters a misfire diagnostic mode, it is determined whether the oxygen heating circuit and the ignition coil share a fuse. When the engine management system judges that the oxygen heating circuit and the ignition coil share the fuse, the fault state of the ignition coil is detected. When the engine management system detects that the number of the ignition coils, of which the fault states indicate faults, of the ignition coils is larger than the preset number and lasts for a second preset time, the engine management system judges that the engine is in fire, and transmits fault signals to the hybrid vehicle controller and the instrument control module. Optionally, the engine management system performs fault dia