Hybrid vehicle control method and hybrid vehicle

Abstract

The invention belongs to the technical field of hybrid vehicles, and discloses a hybrid vehicle control method and a hybrid vehicle. The hybrid vehicle control method comprises the steps that when the inlet and outlet pressure difference of a DPF is larger than or equal to the set passive regeneration pressure difference upper limit value, the SOC value of a battery, the state of an engine and the air inlet temperature of the DPF are obtained in real time; and according to the SOC value of the battery, the state of the engine and the air inlet temperature of the DPF, the specific mode for conducting auxiliary heating on the DPF is determined, and auxiliary heating is conducted on the DPF. The specific mode for conducting auxiliary heating on the DPF comprises the steps that an electric heater is adopted for conducting auxiliary heating on the DPF, and the load of an engine is adjusted for conducting auxiliary heating on the DPF. By the adoption of the hybrid vehicle control method, the efficiency of auxiliary heating of the DPF can be effectively improved, energy consumption caused by auxiliary heating of the DPF can be effectively reduced, 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 studied for their advantages such as low energy consumption and long driving range. Hybrid vehicles have two power sources, one is driven by electric energy and motor, and the other is driven by fuel and engine, so that hybrid vehicles can operate in pure electric working mode, pure engine working mode, or hybrid working mode formed by electric drive and engine drive.

[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 (Selective Catalytic Reduction; SCR), an oxidation catalyst unit (Diesel Oxidation Catalyst; DOC), a particulate capture unit (Diesel Particulate Filter; DPF) and an ammonia oxidation catalyst unit (Ammonia Slip Catalyst; ASC) to form a post-treatment system, and then control the start and stop of the electric heater according to the SOC value of the hybrid vehicle to achieve the purpose of assisting in adjusting the temperature of the DPF to achieve passive regeneration. However, this adjustment 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] The 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 a post-processing system, wherein the post-processing system includes an electric heater, a DOC, and a DPF; wherein the electric heater, the DOC, and the DPF are connected in sequence, and wherein the hybrid vehicle control method includes:

[0007] When the inlet and outlet pressure difference of the DPF is greater than or equal to the set passive regeneration pressure difference upper limit value, the battery SOC value, the engine state and the intake temperature of the DPF are obtained in real time; the engine state includes the engine not started and the 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 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 solution 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 on 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 has been 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 solution of the hybrid vehicle control method, the post-treatment system further includes a mixer and an SCR, and the electric heater, the DOC, the DPF, the mixer and the SCR are connected in sequence; 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 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 temperature of the mixer is greater than or equal to the set urea start-up temperature, and the intake temperature of the SCR is greater than or equal to the set SCR operating temperature, the engine cylinder post-injection is controlled to stop, and the electric heater is controlled to heat according to the engine exhaust flow and the intake temperature of the SCR.

[0018] As a preferred solution 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 and the intake air temperature of the SCR; the first MAP is formed by the engine exhaust flow, 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 solution of the hybrid vehicle control method, the hybrid vehicle control method further includes:

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

[0023] If the battery SOC value is less than the 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 solution of the hybrid vehicle control method, the post-processing 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; 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 controlled to communicate with the outside air to supply air to the electric heater.

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

[0028] When the hybrid vehicle is running 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 solution 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] Determine 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 less than the set mode conversion critical temperature value, the electric heater is started and the blower is started; the electric heater power is obtained from the second MAP according to the intake air temperature of the SCR; 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 electric heater power.

[0033] A hybrid vehicle comprises a post-treatment system, wherein the post-treatment system comprises an electric heater, a DOC and a DPF, wherein the electric heater, the DOC and the DPF are connected in sequence and are used to implement the above hybrid vehicle control method.

[0034] As a preferred solution of the above hybrid vehicle, the post-processing 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 comprises: when the inlet and outlet pressure difference of a DPF is greater than or equal to a set passive regeneration pressure difference upper limit value, a battery SOC value, an engine state and an intake air temperature of the DPF are obtained in real time; if the intake air 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, an electric heater is controlled to perform auxiliary heating on the DPF; if the intake air 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, the electric heater is controlled to perform auxiliary heating on the DPF; if the intake air 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, the engine load is adjusted to perform auxiliary heating on the DPF.

[0037] By adopting the hybrid vehicle control method, the efficiency of auxiliary heating of DPF can be effectively improved, and the energy consumption caused by auxiliary heating of DPF can be effectively reduced with high accuracy, 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 figure:

[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 in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0046] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

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

[0048] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0049] like Figure 1 and Figure 2 As shown, the present invention provides a hybrid vehicle, which includes a post-processing system, and the post-processing system includes an electric heater 1, a DOC3 and a DPF2, and the electric heater 1, the DOC3 and the DPF2 are connected in sequence. The electric heater 1 is arranged before the DOC3, and the exhaust gas flowing through can be heated by the electric heater 1, and the temperature of the exhaust gas transported to the DOC3 can be increased. The heated exhaust gas assists in heating the DOC3 to improve the efficiency of the DOC3 in releasing heat by the oxidation reaction, and the heated exhaust gas assists in heating the DPF2, which can effectively improve the efficiency of the DPF2 in removing particulate matter in the exhaust gas.

[0050] Among them, Figure 1 and Figure 2 As shown, the post-treatment system further includes a mixer 4 and an SCR5, and the electric heater 1, the DOC3, the DPF2, the mixer 4 and the SCR5 are connected in sequence. The heated exhaust gas assists in heating the mixer 4, which can effectively shorten the delay time of urea injection under cold start conditions, and the heated exhaust gas assists in heating the SCR5, which can improve the efficiency of the SCR5 in converting NOx through catalytic reduction reaction.

[0051] Specifically, Figure 1 and Figure 2 As shown, the post-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, and the two SCR5s are connected in sequence. It can be understood that the input end of the upstream SCR5 is connected to the output end of the mixer 4, and the output end of the downstream SCR5 is connected to the input end of the ASC7. Setting two SCR5s can further improve the conversion efficiency of NOx conversion and effectively improve the reliability of the post-treatment system.

[0053] Alternatively, if 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] When the hybrid vehicle is cold-started in pure electric working mode, the electric heater 1 is started synchronously, and the blower 6 is controlled synchronously to communicate 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, SCR5 and ASC7 in sequence after being heated by the electric heater 1, so that the heated air can assist in heating the DOC3, DPF2, mixer 4, SCR5 and ASC7, so that 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, mode, the post-processing system can quickly enter the best working state, thereby effectively improving the robust performance of the post-processing system; secondly, when the hybrid vehicle is running in 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 in real time according to the intake air temperature of SCR5. 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 post-processing system can also quickly enter the best working state, thereby further improving the robust performance of the post-processing system. Among them, the operation of the hybrid vehicle in pure electric working mode refers to the operation process of the hybrid vehicle after the cold start in pure electric working mode is completed.

[0055] Preferably, in this embodiment, if Figure 2 As shown, the blower 6, the electric heater 1, the DOC 3, the DPF 2, the mixer 4, the two SCRs 5, and the ASC 7 are connected in sequence to form an integrated structure that is distributed in a U shape, which can improve the integration of the post-processing system.

[0056] Among them, the specific structures of the 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 in detail.

[0057] Specifically, the input end of DPF2 and the output end of DPF2 are both provided with pressure sensors. The two pressure sensors are used together to detect the pressure difference between the inlet and outlet of DPF2, so as to judge whether the carbon deposition in DPF2 is serious. Specifically, the pressure difference between the inlet and outlet of DPF2 refers to the difference between the inlet pressure of DPF2 and the outlet pressure of DPF2.

[0058] Specifically, a first temperature sensor is also provided at the input end of DPF2. The first temperature sensor can detect the intake temperature of DPF2. It is possible to determine whether the intake temperature of DPF2 reaches the set passive regeneration trigger temperature of DPF2, so as to determine whether DPF2 performs passive regeneration. The passive regeneration trigger temperature is set to an empirical value obtained from a large number of previous tests.

[0059] Specifically, the DOC 3 is provided with a second temperature sensor that can detect the internal temperature of the DOC 3 , so that it can be determined whether the internal temperature of the DOC 3 reaches the set DOC activation temperature, so as to determine whether the DOC 3 performs 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 that the mixing effect of the exhaust gas and urea in the mixer 4 can be determined.

[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] Among them, the hybrid vehicle also includes an engine, a motor, a transmission mechanism, an axle and a battery. When the hybrid vehicle is running in a pure engine working mode, the engine and the axle are connected by a transmission mechanism. When the hybrid vehicle is running in a pure electric working mode, the motor and the axle are connected by a transmission mechanism. When the hybrid vehicle is running in an electric drive-engine drive hybrid working mode, the engine and the motor are both connected to the axle through a transmission mechanism. The battery can supply power to electrical components such as the motor, the electric heater 1 and the blower 6. The engine and the motor can both recover electrical energy and store it in the battery. Among them, the transmission mechanism is a gear transmission mechanism or a planetary gear transmission mechanism. The specific structures of the engine, motor, transmission mechanism, axle and battery belong to the prior art, so they are not repeated 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 operated in a pure engine working mode or an electric drive-engine drive hybrid working mode, the exhaust gas of the engine can be smoothly delivered to the post-treatment system.

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

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

[0066] Specifically, when the inlet and outlet pressure difference of DPF2 is greater than or equal to the set upper limit of the passive regeneration pressure difference, it indicates that the accumulation of particulate matter in DPF2 has reached the upper limit. DPF2 needs to be auxiliary heated to improve the efficiency of DPF2 in removing particulate matter from exhaust gas. The upper limit of the passive regeneration pressure difference is an empirical value obtained from a large number of previous tests.

[0067] When the inlet and outlet pressure difference of the DPF 2 is greater than or equal to the set passive regeneration pressure difference upper limit value, 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 , obtaining the battery SOC value, engine status and intake air temperature of DPF2 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 temperature of DPF2 is greater than or equal to the set passive regeneration trigger temperature, DPF2 can be triggered to perform passive regeneration. The passive regeneration trigger temperature is set to an empirical value obtained from a large number of previous tests. In this embodiment, the passive regeneration trigger temperature is set to 300°C as an example.

[0073] The first set SOC value is an empirical value obtained from a large number of previous tests. 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 the first set SOC value, it indicates that the battery has sufficient power to satisfy the hybrid vehicle to operate in a pure electric working mode and to satisfy the auxiliary heating of DPF2 by the electric heater 1 to achieve the purpose of triggering DPF2 to perform passive regeneration. Secondly, at this time, the working mode of the hybrid vehicle can be a pure engine working mode, a pure electric working mode, or an electric drive-engine drive hybrid working mode, so that the use performance of the hybrid vehicle is better.

[0076] If the intake 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 tests. In this embodiment, the first set SOC value is 70% of the total battery power.

[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 operates in a pure electric working mode. Compared with the energy consumption caused by starting the engine, using the electric heater 1 to assist in heating the DPF2 can effectively reduce energy consumption; and compared with the energy consumption caused by starting the engine, using the electric heater 1 to assist in heating the DPF2 can effectively improve the efficiency of triggering the passive regeneration of the DPF2.

[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, adjusting the engine load to perform auxiliary heating on 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, so it will not be repeated here.

[0083] It is understandable that, since the engine has been started at this time, the hybrid vehicle operates in a pure engine operating mode or an electric drive-engine driving operating mode. By adjusting the engine load to assist in heating DPF2, compared with using the electric heater 1 to assist in heating DPF2, the efficiency of assisting in heating DPF2 can be improved on the basis of reducing energy consumption, so that the purpose of triggering DPF2 for passive regeneration can 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 charge the battery simultaneously to ensure the reliability of the hybrid vehicle from pure engine working mode or electric drive-engine drive working mode to pure electric working mode for driving.

[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 heating of DPF 2. During this process, the battery is charged simultaneously.

[0087] It is understandable that, since the hybrid vehicle is running in pure electric mode at this time and the battery power is low, in order to ensure the efficiency of auxiliary heating of DPF2 and the reliability of the hybrid vehicle running in pure electric mode, it is preferred to start the engine and adjust the engine load to assist in heating DPF2, so that DPF2 can be triggered to perform passive regeneration quickly and efficiently, and the battery can be charged. Specifically, the engine load is increased by adjusting the engine speed and / or adjusting the engine torque and / or adjusting the output power of the engine.

[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 heating of 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 understandable that steps S130, S140, S150, S160, S170 and S180 are parallel steps. When executing the above steps, the specific method of auxiliary heating of DPF2 is selected from steps S130, S140, S150, S160, S170 and S180 or the auxiliary heating of DPF2 is stopped according to the real-time battery SOC value, engine state and the adaptability of the intake temperature of DPF2.

[0095] Furthermore, if the electric heater 1 is used 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 the electric heater 1 from performing auxiliary heating on the DPF2.

[0096] Furthermore, if the auxiliary heating of DPF2 is performed by adjusting the engine load so that the intake temperature of DPF2 is greater than or equal to the set passive regeneration trigger temperature, the specific steps of stopping the auxiliary heating of DPF2 are: stopping adjusting the engine load to perform the auxiliary heating of 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, so that the hybrid vehicle has good performance.

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

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

[0100] S210, control the electric heater 1 to heat at 100% power. At this time, the tail pipe of the engine is connected to the input end of the electric heater 1. The electric heater 1 heats at 100% power to quickly and efficiently heat the exhaust gas of the engine, and the heated exhaust gas quickly and efficiently assists in heating the DOC3, DPF2, mixer 4, SCR5 and ASC7.

[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 DOC3 is lower than the set DOC activation temperature, the process returns to step S210 .

[0103] If the intake air temperature of DOC3 is greater than or equal to the set DOC activation temperature, step S230 is executed.

[0104] Specifically, the DOC activation temperature is set to be the lowest temperature at which the DOC 3 can effectively carry out the oxidation catalytic reaction. The DOC activation temperature is an empirical value obtained from a large number of previous tests. In this embodiment, the DOC activation temperature is 270° C. 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 post-treatment system and the engine temperature, so as to improve the post-treatment efficiency.

[0107] Among them, post-injection in the engine cylinder means that a small amount of fuel is injected after the main injection during the power stroke or exhaust stroke of the engine. This part of the fuel is partially incompletely burned in the high-temperature exhaust gas, so that high-concentration hydrocarbons can be produced and enter the engine exhaust pipe, and finally enter the DOC3 from the engine exhaust pipe for oxidation catalytic reaction and heat release.

[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; 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 setting of the urea spray start temperature refers to the minimum temperature to avoid urea crystallization. The setting of the urea spray start temperature is an empirical value obtained from a large number of previous tests. In this embodiment, the setting of the urea spray start temperature is 190°C as an example.

[0111] The SCR operating temperature is set to be the lowest temperature at which the SCR 5 can effectively perform chemical reactions. The SCR operating temperature is set to be 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 the post-injection in the engine cylinder, and control the electric heater 1 to heat according to the engine exhaust flow and the intake air temperature of SCR5. Stop the post-injection in the cylinder to avoid excessive energy consumption.

[0115] Specifically, the specific steps of controlling the heating of the electric heater 1 according to the engine exhaust flow and the intake air temperature of the SCR5 include: obtaining the electric heater power from the first MAP according to the engine exhaust flow and the intake air temperature of the SCR5; and controlling the heating of the electric heater 1 according to the obtained electric heater power. The first MAP is formed by the engine exhaust flow, the intake air temperature of the SCR5 and the electric heater power. The first MAP is an empirical MAP obtained from a large number of previous tests.

[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 on the basis of 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 the 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 keep the working state.

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

[0122] It is understandable that when the battery SOC value is less than the third set SOC value, it indicates that the battery SOC value is very small. Therefore, in order to ensure that the hybrid vehicle can operate normally when switching to the pure electric working mode or the electric drive-engine driving working mode, the electric heater 1 is controlled to remain in the stopped working state.

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

[0124] In this embodiment, the blower 6, the electric heater 1, the DOC 3, the DPF 2, the mixer 4, the SCR 5 and the ASC 7 are connected in sequence. Figure 5 As shown, the hybrid vehicle control method also 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 synchronously 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 the 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 the pure electric working mode to the pure engine working mode, or from the pure electric working mode to the 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 is running in the 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 .

[0129] Specifically, step S320 includes:

[0130] S321 . Determine in real time whether the intake air temperature of the SCR5 is less than a set mode switching critical temperature value.

[0131] If the intake air temperature of the SCR5 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; 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 is running in 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 in real time according to the intake air temperature of the SCR5, so that when the hybrid vehicle switches from the pure electric working mode to the pure engine working mode, or from the pure electric working mode to the electric drive-engine drive hybrid working mode, the post-processing system can quickly enter the optimal working state, thereby further improving the robust performance of the post-processing system. Specifically, the operation of the hybrid vehicle in pure electric working mode refers to the operation process of the hybrid vehicle after the cold start in the pure electric working mode is completed.

[0135] Specifically, the mode conversion critical temperature value is set to be an empirical value obtained from a large number of previous tests. In this embodiment, the mode conversion 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 clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A hybrid vehicle control method, wherein the hybrid vehicle comprises a post-treatment system, wherein the post-treatment 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 the hybrid vehicle control method comprises: When the inlet and outlet pressure difference of the DPF (2) is greater than or equal to a set passive regeneration pressure difference upper limit value, 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 is 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, adjusting the engine load 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 connected in sequence; and 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 temperature of the mixer (4) is greater than or equal to the set urea injection start temperature, and the intake temperature of the SCR (5) is greater than or equal to the set SCR operating temperature, the engine cylinder post-injection is controlled to stop, and the electric heater (1) is controlled to heat according to the engine exhaust flow rate and the intake 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 pure engine operation mode, the battery SOC value is obtained in real time; If the battery SOC value is less than a third set SOC value, the electric heater (1) is controlled to remain in a stopped working 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-treatment system further comprises a blower (6), the input end of the blower (6) being selectively connectable to 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 a 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 connected in sequence, and the hybrid vehicle control method further comprises: When the hybrid vehicle is running 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 less than the set mode switching 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 a post-treatment system, wherein the post-treatment 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) 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).

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