Hybrid vehicle control method and hybrid vehicle

Abstract

The present application belongs to the technical field of hybrid vehicles, and discloses a hybrid vehicle control method and a hybrid vehicle, wherein the hybrid vehicle control method comprises: when the pressure difference between the inlet and outlet of the DPF is greater than or equal to the set passive regeneration pressure difference upper limit value, obtaining the battery SOC value, the engine state and the inlet temperature of the DPF in real time; determining the specific mode of auxiliary heating for the DPF according to the battery SOC value, the engine state and the inlet temperature of the DPF and performing auxiliary heating on the DPF. The specific mode of auxiliary heating for the DPF comprises: using an electric heater to perform auxiliary heating on the DPF, and adjusting the engine load to perform auxiliary heating on the DPF. By using the hybrid vehicle control method, the efficiency of auxiliary heating for the DPF can be effectively improved, the energy consumption caused by auxiliary heating for the DPF can be effectively reduced, the precision is high, and the use performance of the hybrid vehicle is good.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid vehicles, and in particular to a hybrid vehicle control method and a hybrid vehicle. Background Art

[0002] Hybrid vehicles are widely researched for their low energy consumption and long driving range. They utilize two power sources: electricity and an electric motor, and fuel and an engine. These power sources allow them to operate in pure electric mode, pure engine mode, or a combination of electric and engine modes.

[0003] Among them, for the exhaust emission treatment of hybrid vehicles, the mainstream exhaust treatment method in the current existing technology is to use an electric heater, a selective catalytic reduction unit (SCR), a diesel oxidation catalyst unit (DOC), a particulate filter unit (DPF), and an ammonia slip catalyst unit (ASC) to form an after-treatment system. The electric heater is then controlled to start and stop according to the SOC value of the hybrid vehicle to achieve the purpose of assisting in regulating the temperature of the DPF and realizing passive regeneration. However, this regulation method has high energy consumption and low accuracy, and the efficiency of passive regeneration of the DPF needs to be improved. Summary of the Invention

[0004] An object of the present invention is to provide a hybrid vehicle control method and a hybrid vehicle to solve the above-mentioned problems existing in the prior art when adjusting the DPF for passive regeneration.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A hybrid vehicle control method, wherein the hybrid vehicle includes an aftertreatment system, the aftertreatment system including an electric heater, a DOC, and a DPF; the electric heater, the DOC, and the DPF are sequentially connected, and the hybrid vehicle control method includes:

[0007] When the pressure difference between the inlet and outlet of the DPF is greater than or equal to the set passive regeneration pressure difference upper limit, the battery SOC value, engine status and the intake temperature of the DPF are obtained in real time; the engine status includes engine not started and engine started;

[0008] If the intake air temperature of the DPF is lower than the set passive regeneration trigger temperature and the battery SOC value is greater than or equal to a first set SOC value, controlling the electric heater to perform auxiliary heating on the DPF;

[0009] If the intake air temperature of the DPF is lower than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to a second set SOC value and lower than the first set SOC value, and the engine is not started, controlling the electric heater to perform auxiliary heating on the DPF;

[0010] If the intake air temperature of the DPF is lower than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to the second set SOC value and lower than the first set SOC value, and the engine is started, the engine load is adjusted to perform auxiliary heating on the DPF.

[0011] As a preferred embodiment of the hybrid vehicle control method, if the intake air temperature of the DPF is lower than the set passive regeneration trigger temperature, the battery SOC value is lower than the second set SOC value, and the engine is not started, the engine is started and the engine load is adjusted to perform auxiliary heating of the DPF;

[0012] If the intake air temperature of the DPF is lower than the set passive regeneration trigger temperature, the battery SOC value is lower than the second set SOC value, and the engine is started, adjusting the engine load to perform auxiliary heating on the DPF;

[0013] If the intake air temperature of the DPF is greater than or equal to the set passive regeneration trigger temperature, auxiliary heating of the DPF is stopped.

[0014] As a preferred embodiment of the hybrid vehicle control method, the after-treatment system further includes a mixer and an SCR, and the electric heater, the DOC, the DPF, the mixer, and the SCR are sequentially connected. The hybrid vehicle control method further includes:

[0015] When the hybrid vehicle is cold-started in the pure engine operation mode, the electric heater is controlled to heat at 100% power;

[0016] When the intake air temperature of the DOC is greater than or equal to the set DOC activation temperature, the electric heater is controlled to heat at A% power and the post injection in the engine cylinder is controlled; wherein 0<A<1;

[0017] When the intake air temperature of the mixer is greater than or equal to the set urea injection start temperature, and the intake air temperature of the SCR is greater than or equal to the set SCR operating temperature, the engine cylinder post-injection is stopped, and the electric heater is controlled to heat according to the engine exhaust flow and the intake air temperature of the SCR.

[0018] As a preferred embodiment of the hybrid vehicle control method, the specific steps of controlling the heating of the electric heater according to the engine exhaust flow rate and the intake air temperature of the SCR include:

[0019] The electric heater power is obtained from a first MAP according to the engine exhaust flow rate and the intake air temperature of the SCR; the first MAP is formed by the engine exhaust flow rate, the intake air temperature of the SCR and the electric heater power;

[0020] The electric heater is controlled to heat according to the detected electric heater power.

[0021] As a preferred embodiment of the hybrid vehicle control method, the hybrid vehicle control method further includes:

[0022] When a hybrid vehicle is cold-started in engine-only mode, the battery SOC value is obtained in real time;

[0023] If the battery SOC value is less than a third set SOC value, controlling the electric heater to remain in a stopped state;

[0024] The third set SOC value is smaller than the second set SOC value.

[0025] As a preferred embodiment of the hybrid vehicle control method, the post-processing system further includes a blower, wherein an input end of the blower can be selectively connected to the outside air, and an output end of the blower is connected to an input end of the electric heater; the hybrid vehicle control method further includes:

[0026] When the hybrid vehicle is cold-started in a pure electric working mode, the electric heater is started with a set power when the hybrid vehicle is powered on, and the blower is simultaneously controlled to communicate with the outside air to supply air to the electric heater.

[0027] As a preferred embodiment of the hybrid vehicle control method, the after-treatment system further includes a mixer and an SCR, the electric heater, the DOC, the DPF, the mixer, and the SCR are sequentially connected, and the hybrid vehicle control method further includes:

[0028] When the hybrid vehicle operates in a pure electric working mode, the start and stop of the electric heater, the start and stop of the blower, and the power of the electric heater are controlled according to the intake air temperature of the SCR.

[0029] As a preferred embodiment of the hybrid vehicle control method, the specific steps of controlling the start and stop of the electric heater, the start and stop of the blower, and the power of the electric heater according to the temperature of the SCR include:

[0030] Determining in real time whether the intake air temperature of the SCR is less than a set mode switching critical temperature value;

[0031] If the intake air temperature of the SCR is lower than the set mode switching critical temperature value, the electric heater is activated and the blower is activated; the electric heater power is obtained from the second MAP according to the intake air temperature of the SCR; and the electric heater is controlled to heat according to the obtained electric heater power;

[0032] The second MAP is formed by the intake air temperature of the SCR and the power of the electric heater.

[0033] A hybrid vehicle includes an aftertreatment system, wherein the aftertreatment system includes an electric heater, a DOC, and a DPF, wherein the electric heater, the DOC, and the DPF are sequentially connected and used to implement the above hybrid vehicle control method.

[0034] As a preferred solution of the above hybrid vehicle, the after-treatment system further includes a blower, the input end of the blower can be selectively connected to the outside air, and the output end of the blower is connected to the input end of the electric heater.

[0035] Beneficial effects of the present invention:

[0036] The present invention provides a hybrid vehicle control method and a hybrid vehicle, wherein the hybrid vehicle control method includes: when the inlet and outlet pressure difference of the DPF is greater than or equal to a set passive regeneration pressure difference upper limit value, obtaining a battery SOC value, an engine state and an intake temperature of the DPF in real time; if the intake temperature of the DPF is less than a set passive regeneration trigger temperature and the battery SOC value is greater than or equal to a first set SOC value, controlling an electric heater to perform auxiliary heating on the DPF; if the intake temperature of the DPF is less than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to a second set SOC value and less than the first set SOC value, and the engine is not started, controlling the electric heater to perform auxiliary heating on the DPF; if the intake temperature of the DPF is less than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to the second set SOC value and less than the first set SOC value, and the engine is started, adjusting the engine load to perform auxiliary heating on the DPF.

[0037] By adopting the hybrid vehicle control method, the efficiency of auxiliary heating of the DPF can be effectively improved, and the energy consumption caused by the auxiliary heating of the DPF can be effectively reduced with high precision, so that the performance of the hybrid vehicle is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The principle of the post-processing system of a hybrid vehicle provided by a specific embodiment of the present invention is Figure 1 ;

[0039] Figure 2 The principle of the post-processing system of a hybrid vehicle provided by a specific embodiment of the present invention is Figure 2 ;

[0040] Figure 3 The process of the hybrid vehicle control method provided by the specific embodiment of the present invention is Figure 1 ;

[0041] Figure 4 The process of the hybrid vehicle control method provided by the specific embodiment of the present invention is Figure 2 ;

[0042] Figure 5 The process of the hybrid vehicle control method provided by the specific embodiment of the present invention is Figure 3 .

[0043] In the picture:

[0044] 1. Electric heater; 2. DPF; 3. DOC; 4. Mixer; 5. SCR; 6. Blower; 7. ASC. DETAILED DESCRIPTION

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0046] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0047] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0048] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0049] like Figure 1 and Figure 2 As shown, the present invention provides a hybrid vehicle including an aftertreatment system comprising an electric heater 1, a DOC 3, and a DPF 2, which are sequentially connected. The electric heater 1 is positioned before the DOC 3 to heat the exhaust gas flowing through it, thereby increasing the temperature of the exhaust gas delivered to the DOC 3. The heated exhaust gas assists in heating the DOC 3, thereby increasing the efficiency of heat released by the DOC 3's oxidation reaction. The heated exhaust gas also assists in heating the DPF 2, effectively increasing the efficiency of the DPF 2 in removing particulate matter from the exhaust gas.

[0050] Among them, Figure 1 and Figure 2 As shown, the post-treatment system also includes a mixer 4 and an SCR5. The electric heater 1, DOC 3, DPF 2, mixer 4, and SCR5 are sequentially connected. The heated exhaust gas assists in heating the mixer 4, effectively shortening the urea injection delay during cold start conditions. The heated exhaust gas also assists in heating the SCR5, improving the efficiency of the SCR5's catalytic reduction reaction in converting NOx.

[0051] Specifically, if Figure 1 and Figure 2 As shown, the after-treatment system further includes an ASC7 , and the output end of the SCR5 is connected to the input end of the ASC7 .

[0052] Preferably, if Figure 1 and Figure 2 As shown, there are two SCR5s, which are connected in sequence. It can be understood that the input of the upstream SCR5 is connected to the output of the mixer 4, while the output of the downstream SCR5 is connected to the input of the ASC 7. The installation of two SCR5s can further improve the NOx conversion efficiency and effectively enhance the reliability of the post-treatment system.

[0053] Alternatively, as Figure 2 As shown, the post-processing system further includes a blower 6 , the input end of the blower 6 can be selectively connected to the outside air, and the output end of the blower 6 is connected to the input end of the electric heater 1 .

[0054] For the hybrid vehicle to start in pure electric mode, the electric heater 1 is started synchronously, and the air blower 6 is controlled to communicate with the outside air to send air to the electric heater 1. The air sent to the electric heater 1 is heated by the electric heater 1 and then flows through the DOC 3, the DPF 2, the mixer 4, the SCR 5 and the ASC 7 in turn, so that the heated air can assist in heating the DOC 3, the DPF 2, the mixer 4, the SCR 5 and the ASC 7. Therefore, when the hybrid vehicle switches from pure electric mode to pure engine mode, or from pure electric mode to electric drive-engine drive hybrid mode, the aftertreatment system can quickly enter the optimal working state, thereby effectively improving the robustness of the aftertreatment system. Secondly, when the hybrid vehicle is running in pure electric mode, the start-stop of the electric heater 1 and the start-stop of the air blower 6 are controlled in real time according to the intake temperature of the SCR 5, and the power of the electric heater 1 is controlled. When the hybrid vehicle switches from pure electric mode to pure engine mode, or from pure electric mode to electric drive-engine drive hybrid mode, the aftertreatment system can also quickly enter the optimal working state, thereby further improving the robustness of the aftertreatment system. Wherein, the hybrid vehicle running in pure electric mode refers to the running process after the hybrid vehicle is cold started in pure electric mode.

[0055] Preferably, in the present embodiment, as shown in Figure 2 the integrated structure formed by the air blower 6, the electric heater 1, the DOC 3, the DPF 2, the mixer 4, the two SCRs 5 and the ASC 7 is in U-shaped distribution. The integration of the aftertreatment system can be improved.

[0056] Wherein, the specific structure of the air blower 6, the electric heater 1, the DOC 3, the DPF 2, the mixer 4, the two SCRs 5 and the ASC 7 all belong to the prior art, so they will not be described here.

[0057] Specifically, the input end of the DPF 2 and the output end of the DPF 2 are both provided with pressure sensors. The two pressure sensors are used in cooperation to detect the pressure difference between the inlet and outlet of the DPF 2, so as to judge whether the DPF 2 is seriously carbon deposited. Specifically, the pressure difference between the inlet and outlet of the DPF 2 refers to the difference between the inlet pressure of the DPF 2 and the outlet pressure of the DPF 2.

[0058] Specifically, the input end of the DPF 2 is also provided with a first temperature sensor. The first temperature sensor can detect the inlet temperature of the DPF 2. So as to determine whether the inlet temperature of the DPF 2 reaches the set passive regeneration trigger temperature of the DPF 2, so as to determine whether the DPF 2 is passively regenerated. Wherein, the set passive regeneration trigger temperature is an empirical value obtained from previous experiments.

[0059] Specifically, the DOC 3 is provided with a second temperature sensor capable of detecting the internal temperature of the DOC 3 , so as to determine whether the internal temperature of the DOC 3 has reached the set DOC activation temperature, thereby determining whether the DOC 3 is performing an oxidation catalytic reaction.

[0060] Specifically, the mixer 4 is provided with a third temperature sensor that can detect the internal temperature of the mixer 4 , so as to determine the mixing effect of the exhaust gas and urea in the mixer 4 .

[0061] Specifically, a fourth temperature sensor is provided at the input end of the SCR 5 , and the fourth temperature sensor can detect the intake air temperature of the SCR 5 .

[0062] The hybrid vehicle further includes an engine, a motor, a transmission mechanism, an axle, and a battery. When the hybrid vehicle operates in pure engine mode, the engine and axle are connected via the transmission mechanism. When the hybrid vehicle operates in pure electric mode, the motor and axle are connected via the transmission mechanism. When the hybrid vehicle operates in a hybrid electric-engine mode, both the engine and the motor are connected to the axle via the transmission mechanism. The battery can supply power to electrical components such as the motor, electric heater 1, and blower 6. Both the engine and the motor can recover electrical energy and store it in the battery. The transmission mechanism can be a gear transmission mechanism or a planetary gear transmission mechanism, for example. The specific structures of the engine, motor, transmission mechanism, axle, and battery are all prior art and will not be described in detail here.

[0063] Specifically, the exhaust pipe of the engine can be selectively connected to the input end of the electric heater 1, so that when the hybrid vehicle is running in pure engine mode or electric drive-engine hybrid mode, the exhaust gas of the engine can be smoothly delivered to the after-treatment system.

[0064] The present invention also provides a hybrid vehicle control method, which is used to be implemented in the above hybrid vehicle. Figure 3 As shown, the hybrid vehicle control method includes:

[0065] S110 : During operation of the hybrid vehicle, it is determined in real time whether the pressure difference between the inlet and outlet of the DPF 2 is greater than or equal to a set passive regeneration pressure difference upper limit.

[0066] Specifically, when the pressure differential between the inlet and outlet of DPF 2 is greater than or equal to the set upper limit for passive regeneration, it indicates that the accumulation of particulate matter within DPF 2 has reached the upper limit. Auxiliary heating of DPF 2 is required to improve its efficiency in removing particulate matter from exhaust gas. The upper limit for passive regeneration pressure differential is an empirical value derived from extensive prior testing.

[0067] When the pressure difference between the inlet and outlet of the DPF 2 is greater than or equal to the set passive regeneration pressure difference upper limit, step S120 is executed.

[0068] When the inlet and outlet pressure difference of DPF2 is less than the set passive regeneration pressure difference upper limit, it indicates that DPF2 can operate normally.

[0069] S120 : Obtain the battery SOC value, engine status, and intake air temperature of DPF 2 in real time.

[0070] The engine status includes whether the engine is started or not started.

[0071] If the intake air temperature of the DPF 2 is lower than the set passive regeneration triggering temperature, and the battery SOC value is greater than or equal to the first set SOC value, step S130 is executed.

[0072] It is understood that when the intake air temperature of DPF 2 is greater than or equal to the set passive regeneration trigger temperature, DPF 2 is triggered to perform passive regeneration. The set passive regeneration trigger temperature is an empirical value obtained through extensive prior testing. In this embodiment, the passive regeneration trigger temperature is set at 300°C.

[0073] The first set SOC value is an empirical value obtained from a large number of previous experiments. In this embodiment, the first set SOC value is 80% of the total battery power.

[0074] S130 , controlling the electric heater 1 to perform auxiliary heating on the DPF 2 .

[0075] Specifically, if the battery SOC value is greater than or equal to a first predetermined SOC value, the battery has sufficient charge to both operate the hybrid vehicle in pure electric mode and to assist in heating the DPF 2 via the electric heater 1, thereby triggering passive regeneration of the DPF 2. Furthermore, the hybrid vehicle can now operate in either pure engine mode, pure electric mode, or a hybrid electric-engine mode, enhancing the hybrid vehicle's performance.

[0076] If the intake air temperature of the DPF 2 is lower than the set passive regeneration triggering temperature, the battery SOC value is greater than or equal to the second set SOC value and lower than the first set SOC value, and the engine is not started, step S140 is executed.

[0077] The second set SOC value is an empirical value obtained from a large number of previous experiments. In this embodiment, the first set SOC value is 70% of the total battery power as an example.

[0078] S140 , controlling the electric heater 1 to perform auxiliary heating on the DPF 2 .

[0079] It is understandable that since the engine is not started at this time, the hybrid vehicle is operating in pure electric mode. Compared to the energy consumption caused by starting the engine, using electric heater 1 to assist in heating DPF 2 can effectively reduce energy consumption; and compared to the energy consumption caused by starting the engine, using electric heater 1 to assist in heating DPF 2 can effectively improve the efficiency of triggering DPF 2 for passive regeneration.

[0080] If the intake air temperature of the DPF 2 is lower than the set passive regeneration triggering temperature, the battery SOC value is greater than or equal to the second set SOC value and lower than the first set SOC value, and the engine has been started, step S150 is executed.

[0081] S150: Adjust the engine load to assist in heating DPF 2. During this process, the battery is charged simultaneously.

[0082] Specifically, the engine load is increased by adjusting the engine speed and / or adjusting the engine torque and / or adjusting the engine output power, etc. Specifically, the specific method of increasing the engine load belongs to the prior art and will not be described in detail here.

[0083] It is understood that since the engine is already started at this point, the hybrid vehicle is operating in either a pure engine mode or an electric-drive-engine mode. By adjusting the engine load to assist in heating DPF2, compared to using electric heater 1 to assist in heating DPF2, the efficiency of assisting in heating DPF2 can be improved while reducing energy consumption, thereby enabling the purpose of triggering passive regeneration of DPF2 to be achieved quickly and efficiently.

[0084] Secondly, since the engine has been started and the battery SOC value is relatively low at this time, adjusting the engine load can not only quickly and efficiently achieve the purpose of triggering DPF2 for passive regeneration, but also simultaneously charge the battery to ensure the reliability of the hybrid vehicle when it switches from pure engine operation mode or electric drive-engine drive operation mode to pure electric operation mode.

[0085] If the intake air temperature of the DPF 2 is lower than the set passive regeneration triggering temperature, the battery SOC value is lower than the second set SOC value, and the engine is not started, step S160 is executed.

[0086] S160: Start the engine and adjust the engine load to assist in heating DPF 2. During this process, the battery is simultaneously charged.

[0087] It is understood that since the hybrid vehicle is currently operating in pure electric mode and the battery charge is low, to ensure the efficiency of auxiliary heating of DPF2 and the reliability of the hybrid vehicle operating in pure electric mode, it is preferable to start the engine and adjust the engine load to assist in heating DPF2, so as to both quickly and efficiently trigger passive regeneration of DPF2 and charge the battery. Specifically, the engine load is increased by adjusting the engine speed and / or the engine torque and / or the engine output power.

[0088] If the intake air temperature of the DPF 2 is lower than the set passive regeneration triggering temperature, the battery SOC value is lower than the second set SOC value, and the engine has been started, step S170 is executed.

[0089] S170: Adjust the engine load to assist in heating DPF 2. During this process, the battery is charged simultaneously.

[0090] Specifically, since the engine has been started at this time, compared with using the electric heater 1 to assist in heating the DPF 2 , adjusting the engine load to assist in heating the DPF 2 is more efficient, consumes less energy, and can charge the battery.

[0091] Specifically, the engine load is increased by adjusting the engine speed and / or adjusting the engine torque and / or adjusting the engine output power.

[0092] If the intake air temperature of the DPF 2 is greater than or equal to the set passive regeneration triggering temperature, step S180 is executed.

[0093] S180: Stop auxiliary heating of DPF2.

[0094] It is understood that steps S130, S140, S150, S160, S170, and S180 are parallel steps. When executing the above steps, a specific method for auxiliary heating of the DPF 2 or stopping of auxiliary heating of the DPF 2 is selected from steps S130, S140, S150, S160, S170, and S180 based on the real-time battery SOC value, engine status, and the adaptability of the intake air temperature of the DPF 2.

[0095] Furthermore, if the electric heater 1 is used to auxiliary heat the DPF 2 so that the intake temperature of the DPF 2 is greater than or equal to the set passive regeneration trigger temperature, the specific steps of stopping the auxiliary heating of the DPF 2 are: stopping the electric heater 1 from auxiliary heating the DPF 2 .

[0096] Furthermore, if the engine load is adjusted to perform auxiliary heating on the DPF2 so that the intake temperature of the DPF2 is greater than or equal to the set passive regeneration trigger temperature, the specific steps of stopping the auxiliary heating of the DPF2 are: stopping adjusting the engine load to perform auxiliary heating on the DPF2.

[0097] Therefore, the hybrid vehicle control method can effectively improve the efficiency of auxiliary heating of DPF2 and effectively reduce the energy consumption caused by auxiliary heating of DPF2 with high accuracy, thereby improving the performance of the hybrid vehicle.

[0098] In this embodiment, the electric heater 1, DOC3, DPF2, mixer 4, SCR5 and ASC7 are connected in sequence as an example. For the hybrid vehicle frequently cold-starting and running after starting in pure engine working mode, as shown in FIG. Figure 4 As shown, the hybrid vehicle control method further includes:

[0099] When the hybrid vehicle is cold started in the engine-only operating mode, step S210 is executed.

[0100] S210: Control electric heater 1 to heat at 100% power. At this point, the engine's tailpipe is connected to the input of electric heater 1. Electric heater 1 operates at 100% power to quickly and efficiently heat the engine's exhaust. The heated exhaust quickly and efficiently assists in heating DOC 3, DPF 2, mixer 4, SCR 5, and ASC 7.

[0101] S220 : Determine in real time whether the intake air temperature of DOC3 is greater than or equal to the set DOC activation temperature.

[0102] If the intake air temperature of the DOC 3 is lower than the set DOC activation temperature, the process returns to step S210 .

[0103] If the intake air temperature of the DOC 3 is greater than or equal to the set DOC activation temperature, step S230 is executed.

[0104] Specifically, the DOC activation temperature is the minimum temperature at which the DOC 3 effectively performs the catalytic oxidation reaction. The DOC activation temperature is an empirical value obtained through extensive prior testing. In this embodiment, a DOC activation temperature of 270°C is used as an example.

[0105] S230 , control the electric heater 1 to heat at A% power, and control the post injection in the engine cylinder; 0<A<1.

[0106] Specifically, when the intake temperature of DOC3 is greater than or equal to the set DOC activation temperature, the power of the electric heater 1 can be reduced to reduce the power consumption, so as to ensure the normal operation of the hybrid vehicle when it switches to the pure electric working mode or the electric drive-engine drive working mode; secondly, since the hybrid vehicle is in the pure engine working mode at this time, the use of in-cylinder post-injection can cooperate with the electric heater 1 to effectively increase the temperature of the entire after-treatment system and the engine temperature, so as to improve the after-treatment efficiency.

[0107] Post-injection into the engine cylinder refers to the injection of a small amount of additional fuel after the main injection during the engine's power stroke or exhaust stroke. This fuel is partially incompletely burned in the high-temperature exhaust, resulting in high concentrations of hydrocarbons that enter the engine exhaust pipe. These hydrocarbons eventually enter the DOC3 through the exhaust pipe for oxidation catalytic reaction, releasing heat.

[0108] Wherein, A is an empirical value determined by a large number of previous experiments. In this embodiment, A is 0.5 as an example.

[0109] S240 , determining in real time whether the intake air temperature of the mixer 4 is greater than or equal to the set urea injection start temperature; and determining in real time whether the intake air temperature of the SCR 5 is greater than or equal to the set SCR operating temperature.

[0110] The urea injection start temperature is the minimum temperature required to prevent urea crystallization. The urea injection start temperature is an empirical value obtained from extensive prior testing. In this embodiment, the urea injection start temperature is set to 190°C.

[0111] The SCR operating temperature setting refers to the lowest temperature at which the SCR 5 can effectively perform a chemical reaction. The SCR operating temperature setting is an empirical value obtained from a large number of previous tests. In this embodiment, the SCR operating temperature is set to 230°C as an example.

[0112] If the intake air temperature of the mixer 4 is lower than the set urea injection start temperature, and / or the intake air temperature of the SCR 5 is lower than the set SCR operating temperature, the process returns to step S230 .

[0113] If the intake air temperature of the mixer 4 is greater than or equal to the set urea injection start temperature, and the intake air temperature of the SCR 5 is greater than or equal to the set SCR operating temperature, step S250 is executed.

[0114] S250: Control to stop post-injection in the engine cylinder, and control heating of electric heater 1 based on the engine exhaust flow rate and the intake air temperature of SCR5. Stop post-injection in the cylinder to avoid excessive energy consumption.

[0115] Specifically, the steps for controlling heating of the electric heater 1 based on the engine exhaust flow rate and the intake air temperature of the SCR 5 include: obtaining the electric heater power from a first map based on the engine exhaust flow rate and the intake air temperature of the SCR 5; and controlling heating of the electric heater 1 based on the obtained electric heater power. The first map is formed by the engine exhaust flow rate, the intake air temperature of the SCR 5, and the electric heater power. The first map is an empirical MAP obtained through extensive prior testing.

[0116] By controlling the heating of the electric heater 1 by checking the first MAP, the heating accuracy of the electric heater 1 can be improved while ensuring the auxiliary heating effect, and excessive energy consumption can be further avoided.

[0117] Therefore, for hybrid vehicles that frequently cold start in pure engine operation mode, the above method can effectively reduce the difficulty of frequent cold starts, effectively reduce the energy consumption caused by frequent cold starts, and effectively improve post-processing efficiency.

[0118] The hybrid vehicle control method further includes:

[0119] When a hybrid vehicle is cold started in pure engine operation mode, the battery SOC value is obtained in real time.

[0120] If the battery SOC value is less than the third set SOC value, the electric heater 1 is controlled to remain in the stopped state.

[0121] The third set SOC value is smaller than the second set SOC value.

[0122] It is understood that when the battery SOC value is less than the third set SOC value, it indicates that the battery SOC value is very low. Therefore, in order to ensure normal operation of the hybrid vehicle when switching to the pure electric mode or the electric drive-engine drive mode, the electric heater 1 is controlled to remain in the deactivated state.

[0123] The third set SOC value is an empirical value obtained from a large number of previous experiments. In this embodiment, the third set SOC value is 50% of the total battery power.

[0124] In this embodiment, the blower 6, electric heater 1, DOC3, DPF2, mixer 4, SCR5 and ASC7 are connected in sequence. Figure 5 As shown, the hybrid vehicle control method further includes:

[0125] S310 , when the hybrid vehicle is cold-started in the pure electric working mode, the electric heater 1 is started with the set power when the hybrid vehicle is powered on, and the blower 6 is controlled to communicate with the outside air to supply air to the electric heater 1 .

[0126] The set power is an empirical value obtained from a large number of previous tests. In this embodiment, the electric heater 1 is exemplarily set to start heating at 100% power.

[0127] When the hybrid vehicle is cold-started in pure electric working mode, the electric heater 1 is started synchronously, and the blower 6 is synchronously controlled to connect with the outside air to supply air to the electric heater 1. The air supplied to the electric heater 1 flows through the DOC3, DPF2, mixer 4 and SCR5 in sequence after being heated by the electric heater 1, so that the heated air can assist in heating the DOC3, DPF2, mixer 4 and SCR5. Therefore, when the hybrid vehicle switches from pure electric working mode to pure engine working mode, or from pure electric working mode to electric drive-engine drive hybrid working mode, the after-treatment system can quickly enter the optimal working state, thereby effectively improving the robustness of the after-treatment system.

[0128] S320 : When the hybrid vehicle operates in the pure electric mode, the start and stop of the electric heater 1 , the start and stop of the blower 6 , and the power of the electric heater 1 are controlled according to the intake air temperature of the SCR 5 .

[0129] Specifically, step S320 includes:

[0130] S321 , determining in real time whether the intake air temperature of the SCR 5 is lower than a set mode switching critical temperature value.

[0131] If the intake air temperature of the SCR 5 is lower than the set mode switching critical temperature value, step S322 is executed.

[0132] S322 , start the electric heater 1 and the blower 6 ; obtain the electric heater power from the second MAP according to the intake air temperature of the SCR 5 ; and control the electric heater 1 to heat according to the obtained electric heater power.

[0133] The second MAP is formed by the intake air temperature of the SCR 5 and the electric heater power.

[0134] When the hybrid vehicle operates in pure electric mode, the start and stop of electric heater 1, the start and stop of blower 6, and the power of electric heater 1 are controlled in real time based on the intake air temperature of SCR 5. This allows the aftertreatment system to quickly enter an optimal operating state when the hybrid vehicle switches from pure electric mode to pure engine mode, or from pure electric mode to electric-engine hybrid mode, thereby further improving the robustness of the aftertreatment system. Specifically, the operation of a hybrid vehicle in pure electric mode refers to the operation process of the hybrid vehicle after completing a cold start in pure electric mode.

[0135] Specifically, the mode transition critical temperature value is set to an empirical value obtained from a large number of previous tests. In this embodiment, the mode transition critical temperature value is set to be equal to the set SCR operating temperature. The second MAP is an empirical MAP obtained from a large number of previous tests.

[0136] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A hybrid vehicle control method, wherein the hybrid vehicle includes a post-processing system, wherein the post-processing system includes an electric heater (1), a DOC (3) and a DPF (2); characterized in that: The electric heater (1), the DOC (3) and the DPF (2) are connected in sequence, and the hybrid vehicle control method includes: When the pressure difference between the inlet and outlet of the DPF (2) is greater than or equal to a set passive regeneration pressure difference upper limit, a battery SOC value, an engine state, and an intake air temperature of the DPF (2) are acquired in real time; the engine state includes an engine not started and an engine started; If the intake air temperature of the DPF (2) is lower than the set passive regeneration trigger temperature, and the battery SOC value is greater than or equal to a first set SOC value, controlling the electric heater (1) to perform auxiliary heating on the DPF (2); If the intake air temperature of the DPF (2) is lower than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to a second set SOC value and lower than the first set SOC value, and the engine is not started, then controlling the electric heater (1) to perform auxiliary heating on the DPF (2); If the intake air temperature of the DPF (2) is lower than the set passive regeneration trigger temperature, the battery SOC value is greater than or equal to the second set SOC value and lower than the first set SOC value, and the engine has been started, the engine load is adjusted to perform auxiliary heating on the DPF (2).

2. The hybrid vehicle control method according to claim 1, characterized in that: If the intake air temperature of the DPF (2) is lower than the set passive regeneration trigger temperature, the battery SOC value is lower than the second set SOC value, and the engine is not started, the engine is started and the engine load is adjusted to perform auxiliary heating on the DPF (2); If the intake air temperature of the DPF (2) is lower than the set passive regeneration trigger temperature, the battery SOC value is lower than the second set SOC value, and the engine has been started, the engine load is adjusted to perform auxiliary heating on the DPF (2); If the intake air temperature of the DPF (2) is greater than or equal to the set passive regeneration trigger temperature, auxiliary heating of the DPF (2) is stopped.

3. The hybrid vehicle control method according to claim 1, characterized in that: The post-treatment system further comprises a mixer (4) and an SCR (5), and the electric heater (1), the DOC (3), the DPF (2), the mixer (4) and the SCR (5) are sequentially connected; the hybrid vehicle control method further comprises: When the hybrid vehicle is cold started in a pure engine operation mode, the electric heater (1) is controlled to heat at 100% power; When the intake air temperature of the DOC (3) is greater than or equal to the set DOC activation temperature, the electric heater (1) is controlled to heat at A% power and the post injection in the engine cylinder is controlled; wherein 0<A<1; When the intake air temperature of the mixer (4) is greater than or equal to the set urea injection start temperature, and the intake air temperature of the SCR (5) is greater than or equal to the set SCR operating temperature, the engine cylinder post-injection is stopped, and the electric heater (1) is controlled to heat according to the engine exhaust flow rate and the intake air temperature of the SCR (5).

4. The hybrid vehicle control method according to claim 3, characterized in that: The specific steps of controlling the heating of the electric heater (1) according to the engine exhaust flow rate and the intake air temperature of the SCR (5) include: The electric heater power is obtained from a first MAP according to the engine exhaust flow rate and the intake air temperature of the SCR (5); the first MAP is formed by the engine exhaust flow rate, the intake air temperature of the SCR (5) and the electric heater power; The electric heater (1) is controlled to heat according to the detected electric heater power.

5. The hybrid vehicle control method according to claim 3, characterized in that: The hybrid vehicle control method further includes: When a hybrid vehicle is cold-started in engine-only mode, the battery SOC value is obtained in real time; If the battery SOC value is less than a third set SOC value, controlling the electric heater (1) to remain in a stopped state; The third set SOC value is smaller than the second set SOC value.

6. The hybrid vehicle control method according to claim 1, characterized in that: The post-processing system further comprises a blower (6), the input end of the blower (6) being selectively connectable to the outside air, and the output end of the blower (6) being connectable to the input end of the electric heater (1); the hybrid vehicle control method further comprises: When the hybrid vehicle is cold-started in a pure electric working mode, the electric heater (1) is started synchronously with the set power when the hybrid vehicle is powered on, and the blower (6) is synchronously controlled to communicate with the outside air to supply air to the electric heater (1).

7. The hybrid vehicle control method according to claim 6, characterized in that: The post-treatment system further comprises a mixer (4) and an SCR (5), the electric heater (1), the DOC (3), the DPF (2), the mixer (4) and the SCR (5) are sequentially connected, and the hybrid vehicle control method further comprises: When the hybrid vehicle operates in a pure electric working mode, the start and stop of the electric heater (1), the start and stop of the blower (6) and the power of the electric heater (1) are controlled according to the intake air temperature of the SCR (5).

8. The hybrid vehicle control method according to claim 7, characterized in that: The specific steps of controlling the start and stop of the electric heater (1), the start and stop of the blower (6), and the power of the electric heater (1) according to the temperature of the SCR (5) include: determining in real time whether the intake air temperature of the SCR (5) is less than a set mode switching critical temperature value; If the intake air temperature of the SCR (5) is lower than the set mode conversion critical temperature value, the electric heater (1) is started and the blower (6) is started; the electric heater power is obtained from the second MAP according to the intake air temperature of the SCR (5); and the electric heater (1) is controlled to heat according to the obtained electric heater power; The second MAP is formed by the intake air temperature of the SCR (5) and the electric heater power.

9. A hybrid vehicle comprising an aftertreatment system, wherein the aftertreatment system comprises an electric heater (1), a DOC (3) and a DPF (2), characterized in that: The electric heater (1), the DOC (3) and the DPF (2) are connected in sequence and are used to implement the hybrid vehicle control method according to any one of claims 1 to 8.

10. The hybrid vehicle according to claim 9, characterized in that: The post-processing system further comprises a blower (6), the input end of the blower (6) can be selectively connected to the outside air, and the output end of the blower (6) is connected to the input end of the electric heater (1).

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