Diesel engine range extender DPF parking regeneration control method and system and vehicle

Abstract

The invention relates to a parking regeneration control method and system for a range extender DPF of a diesel engine, and belongs to the technical field of automobile engines. According to the technical scheme, the parking regeneration control method for the diesel engine range extender DPF comprises the steps that S1, whether the parking regeneration condition is met or not is judged; s2, the exhaust temperature of the engine is increased, and the DOC upstream temperature reaches the set temperature value; s3, after-injection is started, the exhaust temperature of the engine is further increased, carbon deposit in the DPF is combusted, and a vehicle power battery is charged in the operation process; and S4, when the carbon loading amount of the DPF is lower than the set carbon loading amount, the engine is shut down after the temperature is reduced. According to the method, the engine utilizes the generator to provide loads, exhaust temperature increase is accelerated, DPF regeneration is promoted, meanwhile, energy generated by engine operation during DPF regeneration is recycled, the aftertreatment temperature is kept to meet the regeneration requirement, parking regeneration time is shortened, noise, loss and oil consumption are reduced, the system energy efficiency is improved, and the negative influence of parking regeneration is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile engines, and in particular to a control method for a diesel engine range extender DPF parking regeneration control system, a diesel engine range extender DPF parking regeneration control system, and a vehicle. Background Art

[0002] The application of diesel engine range extender can achieve an effective balance between the economy and emissions of engine operation, so that the diesel engine always runs in the high-efficiency and economic range, which not only ensures efficient operation, but also avoids the engine running in the low-emission range, greatly reducing the energy consumption and emissions of the whole vehicle during operation.

[0003] Among them, DPF (Diesel Particulate Filter) is used to capture engine particulate matter, thereby reducing the amount of dust emitted into the atmosphere. The particulate matter captured in the DPF can be burned through active regeneration or passive regeneration to ensure the filtering efficiency of the DPF. Active regeneration includes driving regeneration and parking regeneration. Parking regeneration refers to the process of using the energy of the engine exhaust to burn the carbon particles deposited in the DPF when the vehicle is parked. Since the engine operating time is unstable and discontinuous during driving regeneration conditions, driving regeneration cannot completely clean the carbon deposits in the DPF. When the DPF is full of carbon deposits, parking regeneration is required to clean it; parking regeneration is also required for post-processing repair or replacement.

[0004] The diesel engines used in diesel engine range extenders are generally smaller in displacement. Small-displacement diesel engines usually require the fan to work at full load to provide load to increase the exhaust temperature, which generates noise and wastes fuel. Summary of the invention

[0005] Aiming at the problems of noise and fuel waste when a diesel engine range extender performs DPF parking regeneration, the present invention provides a method for controlling DPF parking regeneration of a diesel engine range extender.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is a diesel engine range extender DPF parking regeneration control method, comprising the following steps: S1. ECU receives the parking regeneration command and determines whether the parking regeneration conditions are met and whether the power battery SOC value is lower than the set SOC value; S2. When the parking regeneration conditions are met, reduce the engine throttle valve opening, increase the engine exhaust temperature, preheat the DOC and DPF, and make the DOC upstream temperature reach the set temperature value; S3. Start post-injection to further increase the engine exhaust temperature, burn the carbon deposits in the DPF, and calculate the current remaining DPF carbon load. During operation, the vehicle power battery is charged; S4. When the DPF carbon load is lower than the set carbon load or the regeneration time reaches the set time, the engine idles without load, and the engine stops after the temperature is reduced to complete the parking regeneration.

[0007] In this regeneration method, the engine uses the generator to provide load, that is, the range extender generates electricity by driving the generator through the engine to provide a larger load. At the same time, the engine operates in a high-efficiency range, which accelerates the increase in exhaust temperature and promotes DPF regeneration. At the same time, it recovers the energy generated by the engine operation during DPF regeneration, maintains the post-processing temperature to meet the regeneration requirements, reduces the time, noise, loss and fuel consumption of parking regeneration, improves system energy efficiency, and reduces the negative impact of parking regeneration.

[0008] Preferably, the parking regeneration conditions include the engine coolant temperature, the engine operating status and the vehicle status: determine whether the engine coolant temperature meets the regeneration requirements, if it does, proceed to S2, if not, the engine operates at the bench-calibrated hot engine condition until the engine coolant temperature meets the requirements.

[0009] Preferably, in step S2, the set temperature value of the DOC upstream temperature is 180 degrees; Step S3 includes: S3-1. Open the rear spray to further increase the engine exhaust temperature and preheat the DOC and DPF to make the DOC upstream temperature reach 280 degrees; S3-2. Turn on the second post-injection to further increase the engine exhaust temperature, making the temperature upstream of the DPF reach 600°C; When the temperature upstream of DPF reaches 600℃, the carbon deposits in DPF burn.

[0010] Preferably, in step S3, the generator is controlled to provide load according to the engine speed and required torque, and parking charging is performed through the parking charging module to ensure that the generator provides sufficient load for the engine and charges the power battery at the same time.

[0011] Preferably, in step S4, when the carbon loading drops below 0.2 g / L or reaches a predetermined regeneration time, the regeneration process is automatically terminated.

[0012] On the other hand, the present invention also provides a diesel engine range extender DPF parking regeneration control system, which adopts the above-mentioned diesel engine range extender DPF parking regeneration control method, and the system includes: The engine controller ECU determines whether the driver's parking regeneration intention and parking regeneration conditions are met; DPF regeneration control module controls the exhaust temperature; The engine thermal management module controls the engine operation according to the temperature conditions during the regeneration process, monitors the temperature of each system, and controls the operation of the engine thermal management accessories to the lowest energy consumption state; The parking charging module charges the power battery until the regeneration process is completed.

[0013] Preferably, the thermal management module operates the engine according to the optimal thermal engine conditions of the bench test to reach the required engine coolant temperature; during the regeneration process, the thermal management module controls the electronic thermostat, the electronically controlled silicone oil water pump, and the electronically controlled silicone oil fan in sequence according to priority while ensuring the safety of the engine coolant temperature, so that the cooling system always runs at the lowest power consumption, reducing fuel consumption and noise.

[0014] Preferably, the DPF parking regeneration control module includes an intake throttle valve control module, which is used to control the opening of the intake throttle valve located on the intake pipe of the engine; the throttle valve is not fully opened in the initial stage of parking regeneration. The throttle valve is properly closed in the initial stage of parking regeneration to increase the engine back pressure and the exhaust temperature, thereby effectively improving the DPF regeneration efficiency.

[0015] Preferably, a safety monitoring and fault diagnosis module is also included to continuously monitor the operating status of the engine, DPF and battery during the entire regeneration process.

[0016] In a third aspect, the present invention further provides a parking regeneration control method for the diesel engine range extender DPF of the vehicle.

[0017] It can be seen from the above technical scheme that the advantages of the present invention are: this scheme provides a load for the engine through a generator to increase the engine exhaust temperature, accelerates the exhaust temperature increase to promote DPF regeneration, and can recover the energy generated by the engine operation during DPF regeneration, thereby reducing fan noise; using a generator to provide a load to increase the exhaust temperature can reduce the post-injection volume, reduce fuel consumption, and reduce the risk of oil dilution; furthermore, the system and vehicle provided by the present invention have high DPF regeneration efficiency and high fuel utilization; it has complete process monitoring, realizes closed-loop control, and improves the service life and safety of vehicle components. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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.

[0019] Figure 1 This is a flow chart of a method according to Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in this specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent.

[0021] Embodiment 1 like Figure 1 As shown, a diesel engine range extender DPF parking regeneration control method comprises the following steps: S1. ECU receives a parking regeneration command. For example, a parking regeneration switch is provided on the vehicle. When the driver presses the parking regeneration switch, the parking regeneration command is sent to ECU. Then, it is determined whether the parking regeneration conditions are met, which include the vehicle status (whether it is stationary, whether the handbrake is pulled up), the engine coolant temperature and the engine running status, and whether the power battery SOC value (battery charging state) is lower than the set SOC value (obtained by calibration). If the conditions are not met, the reasons for not meeting the conditions are prompted. If the engine coolant temperature is insufficient, the engine is operated at the bench calibrated hot engine condition until the engine coolant temperature meets the requirements; S2. When the parking regeneration conditions are met, the parking regeneration process is started. The vehicle's engine thermal management module operates the engine to reach the required engine coolant temperature according to the best thermal engine working conditions tested on the bench. During the entire regeneration process, the engine thermal management module controls the electronic thermostat, the electronically controlled silicone oil water pump, and the electronically controlled silicone oil fan in order of priority while ensuring the safety of the engine coolant temperature, so that the cooling system always runs at the lowest power consumption. It can ensure that the engine coolant temperature, oil temperature, and intake air temperature meet the requirements during engine regeneration, and reduce noise and fuel consumption.

[0022] The DPF regeneration control module operates the engine according to the highest efficiency point obtained by bench testing (testing on the bench is required during the development of the range extender to determine the optimal efficiency range of the engine regeneration condition), while reducing the engine throttle valve opening, increasing the engine exhaust temperature, and preheating the DOC and DPF to make the DOC upstream temperature reach 180 degrees; S3. On the basis of S2, the first post injection is started to further increase the engine exhaust temperature, further preheat the DOC and DPF, and make the DOC upstream temperature reach 280 degrees; Then, the second post-injection is turned on to further increase the engine exhaust temperature, so that the temperature upstream of the DPF reaches about 600°C, so that the carbon deposits in the DPF are burned, and the current remaining DPF carbon load is calculated while the combustion is in progress; In the above process, the DPF regeneration control module operates the engine at the optimal efficiency point of the regeneration condition obtained by the bench test to ensure that the carbon deposits in the DPF can be fully burned under the most economical conditions, and at the same time charge the power battery with the highest energy efficiency. The DPF parking regeneration control module includes an intake throttle valve control module, which is used to control the opening of the intake throttle valve located on the intake pipe of the engine; the throttle valve is properly closed in the initial stage of parking regeneration to increase the engine back pressure and increase the exhaust temperature, thereby effectively improving the DPF regeneration efficiency. The post-injection strategy uses the injector to spray after the far top dead center. This part of the unburned diesel enters the DOC with the exhaust gas to oxidize and release heat, further increasing the exhaust temperature, causing the internal temperature of the DPF to reach about 600℃, ensuring the complete combustion of carbon deposits. The generator provides load to cooperate with the intake throttle valve to worsen the combustion, and then adds post-injection, precise control, and comprehensive use, which can make the exhaust temperature quickly meet the regeneration requirements and ensure the stability of the exhaust temperature, thereby realizing efficient regeneration of the post-treatment system.

[0023] Furthermore, the DPF regeneration control module includes an exhaust temperature control module, which controls the exhaust temperature according to the exhaust temperature demand value transmitted by the engine ECU control module. The exhaust temperature is obtained by temperature sensors arranged on the engine's post-processing, which are the DOC upstream temperature sensor, the DPF upstream temperature sensor, and the SCR upstream temperature sensor. The exhaust temperature control module compares the real-time exhaust temperature with the exhaust temperature demand value, and continuously controls the real-time exhaust temperature according to the comparison result. The exhaust temperature is controlled by a closed-loop control mode, which can effectively ensure that during the DPF regeneration process, the exhaust temperature continues to meet the regeneration conditions until the regeneration process ends.

[0024] S4. The regeneration completion is judged based on the real-time monitoring data of the DPF carbon load. When the carbon load drops below 0.2g / L or reaches the preset regeneration time, the regeneration process is automatically terminated to ensure the recovery of DPF performance while avoiding waste of resources or even damage to post-processing components caused by excessive regeneration. It is judged whether the DPF carbon load is less than 0.2g / L or the regeneration time reaches the set time. If so, the DPF carbon deposit cleaning completion conditions are met. At this time, the engine is allowed to idle without load, and the post-processing temperature, oil temperature, and engine coolant temperature are reduced. When the temperature is lower than the set value, the engine is shut down to complete the parking regeneration.

[0025] In the above process, when the engine needs load, the generator provides the load. When the generator provides load, the power battery can be charged through the parking charging module. During the regeneration process, the parking charging module controls the generator to perform parking charging according to the engine speed and required torque. The charging strategy is dynamically adjusted during the regeneration process to ensure that the generator provides sufficient load for the engine while charging the power battery. The safety monitoring and fault diagnosis module continuously monitors the operating status of key components such as the engine, DPF, and battery during the entire regeneration process. Once an abnormal situation is found, such as excessive temperature, abnormal battery voltage, or system failure, immediate measures are taken to interrupt regeneration to ensure system safety and prevent equipment damage.

[0026] Embodiment 2 Based on the method provided in the first embodiment, and the vehicle control module involved therein, this embodiment further provides a diesel engine range extender DPF parking regeneration control system, using the method provided in the first embodiment, the system includes: The engine controller ECU determines whether the driver's parking regeneration intention and parking regeneration conditions are met; DPF regeneration control module controls the exhaust temperature; The engine thermal management module controls the engine operation according to the temperature conditions during the regeneration process, monitors the temperature of each system, and controls the operation of the engine thermal management accessories at the lowest energy consumption state. The engine thermal management module includes an electronically controlled silicone oil fan, an electronically controlled silicone oil water pump, an electronic thermostat, and an engine coolant temperature sensor. The thermal management module operates the engine according to the optimal thermal engine conditions of the bench test to achieve the required engine coolant temperature. During the regeneration process, the thermal management module controls the electronic thermostat, the electronically controlled silicone oil water pump, and the electronically controlled silicone oil fan in sequence according to priority while ensuring the safety of the engine coolant temperature, so that the cooling system always operates at the lowest power consumption, thereby reducing fuel consumption and noise.

[0027] The generator controller GCU and the parking charging module charge the power battery until the regeneration process is completed.

[0028] The DPF parking regeneration control module includes an intake throttle valve control module, which is used to control the opening of the intake throttle valve located on the intake pipe of the engine; the throttle valve is not fully opened in the initial stage of parking regeneration, that is, the throttle valve is properly closed in the initial stage of parking regeneration to increase the engine back pressure and improve the exhaust temperature, thereby effectively improving the DPF regeneration efficiency.

[0029] The safety monitoring and fault diagnosis module continuously monitors the operating status of the engine, DPF and battery during the entire regeneration process.

[0030] Embodiment 3 This embodiment provides a vehicle, which adopts the diesel engine range extender DPF parking regeneration control method provided in the first embodiment.

[0031] It can be seen from the above embodiments that the beneficial effect of the present invention lies in that the present scheme provides a load for the engine through the generator to increase the engine exhaust temperature, accelerates the exhaust temperature increase and promotes DPF regeneration, and can recover the energy generated by the engine operation during DPF regeneration, thereby reducing fan noise; using the generator to provide a load to increase the exhaust temperature can reduce the post-injection volume, reduce fuel consumption, and reduce the risk of oil dilution; furthermore, the system and vehicle provided by the present invention have high DPF regeneration efficiency and high fuel utilization; have complete process monitoring, realize closed-loop control, and improve the service life and safety of vehicle components.

[0032] 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 diesel engine range extender DPF parking regeneration control method, characterized in that: The following steps are involved: S1. ECU receives the parking regeneration command and determines whether the parking regeneration conditions are met and whether the power battery SOC value is lower than the set SOC value; S2. When the parking regeneration conditions are met and the SOC is lower than the set SOC value, the engine throttle opening is reduced, the engine exhaust temperature is increased, the DOC and DPF are preheated, and the DOC upstream temperature reaches the set temperature value; S3. Start post-injection to further increase the engine exhaust temperature, burn the carbon deposits in the DPF, and calculate the current remaining DPF carbon load. During operation, the vehicle power battery is charged; S4. When the DPF carbon load is lower than the set carbon load or the regeneration time reaches the set time, the engine idles without load, and the engine stops after the temperature is reduced to complete the parking regeneration.

2. The diesel engine range extender DPF parking regeneration control method according to claim 1, characterized in that: The parking regeneration conditions include the engine coolant temperature, the engine operating status and the vehicle status: determine whether the engine coolant temperature meets the regeneration requirements. If it does, proceed to S2. If not, the engine is operated at the bench-calibrated hot engine condition until the engine coolant temperature meets the requirements.

3. The diesel engine range extender DPF parking regeneration control method according to claim 1, characterized in that: In step S2, the set temperature value of the DOC upstream temperature is 180 degrees; Step S3 includes: S3-1. Open the rear spray to further increase the engine exhaust temperature and preheat the DOC and DPF to make the DOC upstream temperature reach 280 degrees; S3-2. Open the second post-injection to further increase the engine exhaust temperature, making the temperature upstream of the DPF reach 600°C; When the temperature upstream of DPF reaches 600℃, the carbon deposits in DPF burn.

4. The diesel engine range extender DPF parking regeneration control method according to claim 1, characterized in that: In step S3, the generator is controlled to provide load according to the engine speed and required torque, and parking charging is performed through the parking charging module to ensure that the generator provides sufficient load for the engine and charges the power battery at the same time.

5. The diesel engine range extender DPF parking regeneration control method according to claim 1, characterized in that: In step S4, when the carbon loading drops below 0.2 g / L or reaches a predetermined regeneration time, the regeneration process is automatically terminated.

6. A diesel engine range extender DPF parking regeneration control system, characterized in that: include: The engine controller ECU determines whether the driver's parking regeneration intention and parking regeneration conditions are met; DPF regeneration control module controls the exhaust temperature; The engine thermal management module controls the engine operation according to the temperature conditions during the regeneration process, monitors the temperature of each system, and controls the operation of the engine thermal management accessories to the lowest energy consumption state; The parking charging module charges the power battery until the regeneration process is completed.

7. The diesel engine range extender DPF parking regeneration control system according to claim 6, characterized in that: The thermal management module operates the engine according to the optimal thermal engine conditions of the bench test to achieve the required engine coolant temperature; during the regeneration process, the thermal management module controls the electronic thermostat, electronically controlled silicone oil water pump, and electronically controlled silicone oil fan in sequence according to priority while ensuring the safety of the engine coolant temperature, so that the cooling system always runs at the lowest power consumption, reducing fuel consumption and noise.

8. The diesel engine range extender DPF parking regeneration control system according to claim 6, characterized in that: The DPF parking regeneration control module includes an intake throttle valve control module, which is used to control the opening of an intake throttle valve located on the intake pipe of the engine; the throttle valve is not fully opened in the initial stage of parking regeneration.

9. The diesel engine range extender DPF parking regeneration control system according to claim 6, characterized in that: It also includes a safety monitoring and fault diagnosis module, which continuously monitors the operating status of the engine, DPF and battery during the entire regeneration process.

10. A vehicle, characterized in that: A diesel engine range extender DPF parking regeneration control method as described in any one of claims 1 to 5 is adopted.

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