CN115234412A - Exhaust gas recirculation system, control method, engine and vehicle - Google Patents

Abstract

The invention provides an exhaust gas recirculation system, a control method, an engine and a vehicle, wherein the exhaust gas recirculation system comprises: the intake and exhaust assembly comprises a plurality of cylinders, an exhaust device and a tail pipe; the exhaust device comprises a waste gas recovery pipeline, wherein a waste gas recovery device is arranged on the waste gas recovery pipeline, an exhaust port of one of the cylinders is connected with an inlet of the waste gas recovery pipeline, an outlet of the waste gas recovery pipeline is connected with an air inlet of each cylinder, and exhaust ports of the rest cylinders in the cylinders are connected with an exhaust tail pipe through an exhaust device; the warm-up exhaust tail pipeline is positioned between the exhaust device and the exhaust tail pipe and comprises an engine oil heating device for exchanging heat with engine oil in the oil pan; the energy recovery exhaust tail pipe is positioned between the exhaust device and the exhaust tail pipe and comprises an exhaust gas storage tank and a power generation device, wherein the power generation device is used for converting the energy of the exhaust gas in the exhaust gas storage tank into electric energy so as to solve the problem that the EGR rate of each cylinder in the EGR system in the prior art is low.

Description

Exhaust gas recirculation system, control method, engine and vehicle

technical field

The invention relates to the technical field of engines, in particular, to an exhaust gas recirculation system, a control method, an engine and a vehicle.

Background technique

At present, domestic passenger car products are still dominated by gasoline engines. Although hybrid power can be used to reduce emissions at lower speeds, there are still problems with exhaust valves.

Under the background of carbon peaking and carbon neutrality, the electrification of vehicle power has become the development trend of the industry. It is predicted in the "Energy Saving and New Energy Vehicle Technology Roadmap 2.0" that by 2035, internal combustion engine power and new energy power will be respectively It accounts for 50% of the power of passenger cars, while 100% of internal combustion engine power will be applied to cars in the form of hybrid power.

Japanese car companies represented by Toyota have applied Atkinson cycle, high compression ratio, external cooling EGR and low friction technologies to develop hybrid power systems on the basis of traditional large-displacement naturally aspirated engines. For gasoline engine products in passenger cars, carbon dioxide emission reduction can reach more than 20%, which is the leading level in the hybrid passenger car industry, but this still cannot fundamentally solve the emission problem caused by gasoline combustion. With the implementation of China 6b emission regulations approaching in 2023, all OEMs have begun to carry out technology research and development according to China 7 emission regulations. The lifeblood of the industry, and EGR technology can reduce knocking tendency and pumping loss, improve fuel economy, and is an important development direction of energy-saving technology routes. At the same time, hydrogen, as a clean energy, can be used to replace gasoline and fundamentally solve the emission problem.

For the EGR (exhaust gas recirculation) system of a three-cylinder hydrogen engine, because the ignition interval of the three-cylinder engine and the four-cylinder engine are different, the exhaust pulse interval is also different. Relatively speaking, the exhaust pressure of the three-cylinder engine Higher, the exhaust energy is greater, but the exhaust pulse interval is longer and the EGR rate is lower. Under the same EGR arrangement, the EGR rate of the three-cylinder engine is more uneven than that of the four-cylinder engine. There are many patents on the EGR system applied to the four-cylinder engine, but these patents are not applicable to the three-cylinder engine.

In the cold start stage of the car, since the water temperature in the engine is much lower than the temperature during normal operation (90°C), the fuel consumption and emissions of the engine are relatively poor during the slow heating process. Therefore, the engine warm-up time is shortened to achieve fast Warming up the engine can significantly reduce the fuel consumption rate of the engine and improve the emission of harmful pollutants. In addition, during the normal operation stage of the engine, the EGR rate of the exhaust gas recirculation system will be limited due to the high exhaust gas temperature. Usually the maximum EGR rate will not exceed 25%, and the energy of the exhaust gas cannot be fully utilized, which saves fuel. potential to be further improved.

Contents of the invention

The main purpose of the present invention is to provide an exhaust gas recirculation system, a control method, an engine and a vehicle to solve the problem that the EGR rate of each cylinder is relatively low in the EGR system in the prior art.

In order to achieve the above object, according to an aspect of the present invention, an exhaust gas recirculation system is provided, comprising: an intake and exhaust assembly, including a plurality of cylinders, an exhaust device and an exhaust tail pipe; an exhaust gas recovery line, an exhaust gas recovery pipe An exhaust gas recovery device is arranged on the road, the exhaust port of one of the multiple cylinders is connected to the inlet of the exhaust gas recovery pipeline, the outlet of the exhaust gas recovery pipeline is connected to the intake ports of each cylinder, and the remaining cylinders in the multiple cylinders are connected The exhaust ports are connected to the exhaust tail pipe through the exhaust device; the warm-up exhaust tail pipe is located between the exhaust device and the exhaust tail pipe. The oil heating device for heat exchange of the oil inside; the energy recovery exhaust tail pipe is located between the exhaust device and the exhaust tail pipe, and the energy recovery exhaust tail pipe is provided with an exhaust gas storage tank and a power generation device. It is used to convert the energy of the exhaust gas in the exhaust gas storage tank into electrical energy.

Further, a total flow sensor is arranged on the exhaust gas recovery pipeline to detect the total flow of gas in the exhaust gas recovery pipeline; wherein, the total flow sensor is set at the exhaust port of the exhaust gas recovery device close to the cylinder connected to it One side; and/or a main valve is set on the exhaust gas recovery pipeline to control the on-off of the corresponding exhaust gas recovery pipeline through the main valve; wherein, the main valve is set at the exhaust port of the exhaust gas recovery device close to the cylinder connected to it and/or the plurality of cylinders includes a first cylinder, a second cylinder and a third cylinder, the exhaust port of one of the first cylinder, the second cylinder and the third cylinder is connected to the exhaust gas recovery pipeline, and the first The other two exhaust ports of the cylinder, the second cylinder and the third cylinder are all connected with the exhaust device.

Further, the exhaust gas recovery pipeline includes a plurality of intake branch pipelines, the outlets of the multiple intake branch pipelines are connected to the intake ports of the multiple cylinders in a one-to-one correspondence, and the inlets of each intake branch pipeline are connected to the exhaust gas recovery device. .

Further, each intake sub-pipeline is provided with a sub-pipeline flow sensor for detecting the flow of gas in the corresponding intake sub-pipeline; and/or each intake sub-pipeline is provided with an intake valve to pass through the intake valve To control the on-off of the corresponding intake sub-pipelines and the flow of gas in the corresponding intake sub-pipelines.

Further, the intake and exhaust assembly includes an intake device and a plurality of intake manifolds, the inlets of the plurality of intake manifolds are connected to the outlets of the intake device, and the outlets of the plurality of intake manifolds are connected to the inlets of the plurality of cylinders. The air ports are connected in one-to-one correspondence; and/or the intake and exhaust assembly includes a plurality of exhaust manifolds, and the inlets of the plurality of exhaust manifolds are connected in one-to-one correspondence with the exhaust ports of the plurality of cylinders.

Further, an oil temperature sensor is arranged in the oil pan to detect the temperature of the oil in the oil pan; and/or an oil heating valve is arranged on the exhaust pipe of the warm-up engine, so as to control the warm-up through the oil heating valve. On-off of the exhaust pipe of the engine, wherein the oil heating valve is arranged on the side of the oil heating device close to the exhaust device; and/or the energy recovery exhaust pipe is provided with an energy recovery valve to pass the energy recovery valve to control the on-off of the energy recovery exhaust tail pipeline, wherein the energy recovery valve is arranged on the side of the exhaust gas storage tank close to the exhaust device; and/or the power generation device is used for connecting with the battery to supply power to the battery.

According to the second aspect of the present invention, there is provided an exhaust gas recirculation control method, the exhaust gas recirculation control method is used to control the above exhaust gas recirculation system; the exhaust gas recirculation control method includes: when the engine is in the working state, always open the The main valve of the recovery pipeline; adjust the exhaust gas recirculation rate of each cylinder by controlling the flow of gas flowing from the exhaust gas recovery pipeline to the intake port of each cylinder.

Further, when the engine is in the working state, the exhaust gas recirculation control method further includes: when the real-time temperature T of the engine oil is lower than the preset temperature _T0 , controlling the connection of the warm-up exhaust tail pipe, and controlling the energy recovery exhaust tail pipe The circuit is disconnected to heat the oil through the oil heating device; when the real-time temperature T of the oil is greater than or equal to the preset temperature T ₀ , the exhaust tail pipe of the warm-up engine is controlled to be disconnected, and the exhaust tail pipe of the energy recovery is controlled connected to generate electricity through the generator.

According to a third aspect of the present invention, an engine is provided, including the above exhaust gas recirculation system.

According to a fourth aspect of the present invention, there is provided a vehicle including the above-mentioned engine.

Applying the technical solution of the present invention, the exhaust gas recirculation system of the present invention includes: intake and exhaust components, including a plurality of cylinders, exhaust devices and exhaust tailpipes; exhaust gas recovery pipelines, exhaust gas recovery devices are arranged on the exhaust gas recovery pipelines, The exhaust port of one of the plurality of cylinders is connected to the inlet of the exhaust gas recovery pipeline, the outlet of the exhaust gas recovery pipeline is connected to the intake port of each cylinder, and the exhaust ports of the remaining cylinders in the plurality of cylinders are all connected through exhaust The gas device is connected to the exhaust tail pipe; the warm-up exhaust tail pipe is located between the exhaust device and the exhaust tail pipe, and the warm-up exhaust tail pipe is provided with a heat exchange device for heat exchange with the oil in the oil pan. Oil heating device; energy recovery exhaust tail pipe, located between the exhaust device and the exhaust tail pipe, the energy recovery exhaust tail pipe is equipped with an exhaust gas storage tank and a power generation device, and the power generation device is used to convert the exhaust gas in the exhaust gas storage tank The energy of the exhaust gas is converted into electrical energy. The exhaust gas recirculation system of the present invention can make full use of the high exhaust energy of the three-cylinder hydrogen engine to increase the EGR rate by connecting the exhaust port of one of the multiple cylinders with the inlet of the exhaust gas recovery pipeline, so as to solve the problem of the prior art In the EGR system, the EGR rate of each cylinder is relatively low, and the exhaust gas recirculation system of the present invention can control the EGR rate of each cylinder by controlling the flow of exhaust gas flowing to each cylinder, so as to solve the problem of the three-cylinder hydrogen engine. The problem of uneven EGR rate of each cylinder fully exerts the fuel-saving potential of the exhaust gas recirculation system; at the same time, the exhaust gas recirculation system of the present invention is utilized by setting the warm-up exhaust tail pipeline and the energy recovery exhaust tail pipeline The heat of the exhaust gas heats the engine oil in the oil pan and generates electricity, which realizes rapid heating of the engine oil and energy recovery, which is conducive to the popularization and application of hybrid power, and can improve the power and economy of the engine.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

FIG. 1 shows a schematic structural view of an embodiment of an exhaust gas recirculation system according to the present invention;

Fig. 2 shows a simple schematic diagram of the EGR control method according to the present invention;

Fig. 3 shows the flowchart of the first embodiment of the EGR control method of the present invention;

Fig. 4 shows a flowchart of the second embodiment of the EGR control method of the present invention.

Wherein, the above-mentioned accompanying drawings include the following reference signs:

1. Inlet and exhaust assembly; 11. Cylinder; 111. First cylinder; 112. Second cylinder; 113. Third cylinder; 12. Exhaust device; 13. Exhaust tailpipe; 14. Air intake device; 15. Intake manifold; 151, first intake manifold; 152, second intake manifold; 153, third intake manifold; 16, air filter; 17, exhaust manifold; 171, first Exhaust manifold; 172, the second exhaust manifold; 173, the third exhaust manifold;

2. Exhaust gas recovery pipeline; 21. Exhaust gas recovery device; 22. Total flow sensor; 23. Main valve; 24. Intake sub-pipeline; 241. First intake sub-pipeline; , the third air intake sub-pipeline; 25, the sub-pipeline flow sensor; 251, the first sub-pipeline flow sensor; 252, the second sub-pipeline flow sensor; 253, the third sub-pipeline flow sensor; 26, the intake valve; The first intake valve; 262, the second intake valve; 263, the third intake valve;

3. Warm-up exhaust tail pipe; 31. Oil heating device; 32. Oil temperature sensor; 33. Oil heating valve;

4. Energy recovery exhaust tail pipeline; 41. Exhaust gas storage tank; 42. Power generation device; 43. Energy recovery valve;

5. Oil pan;

6. Battery.

Detailed ways

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. In order to facilitate the understanding of the present invention, the following will describe the present invention more fully with reference to the accompanying drawings and examples. Although the preferred embodiments of the invention are shown in the drawings, the invention may be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

Example 1

As shown in Figure 1, the present invention provides an exhaust gas recirculation system, comprising: an intake and exhaust assembly 1, including a plurality of cylinders 11, an exhaust device 12 and an exhaust tailpipe 13; an exhaust gas recovery pipeline 2, the exhaust gas recovery The pipeline 2 is provided with an exhaust gas recovery device 21, the exhaust port of one of the multiple cylinders 11 is connected to the inlet of the exhaust gas recovery pipeline 2, and the outlet of the exhaust gas recovery pipeline 2 is connected to the air inlet of each cylinder 11, The exhaust ports of the remaining cylinders 11 in the plurality of cylinders 11 are all connected to the exhaust tail pipe 13 through the exhaust device 12; the warm-up exhaust tail pipe 3 is located between the exhaust device 12 and the exhaust tail pipe 13 , the warm-up exhaust tail pipe 3 is provided with an oil heating device 31 for heat exchange with the oil in the oil pan 5; the energy recovery exhaust tail pipe 4 is located between the exhaust device 12 and the exhaust tail pipe 13 Between them, the energy recovery exhaust tail pipe 4 is provided with an exhaust gas storage tank 41 and a power generation device 42, and the power generation device 42 is used to convert the energy of the exhaust gas in the exhaust gas storage tank 41 into electric energy.

The exhaust gas recirculation system of the present invention can make full use of the high exhaust energy of the three-cylinder hydrogen engine to increase the EGR rate by connecting the exhaust port of one of the multiple cylinders 11 with the inlet of the exhaust gas recovery pipeline 2 to solve the current problem. In the EGR system in the prior art, the EGR rate of each cylinder is relatively low, and the exhaust gas recirculation system of the present invention can control the EGR rate of each cylinder 11 by controlling the flow rate of the exhaust gas flowing into each cylinder 11, so as to solve the three problems The EGR rate unevenness of each cylinder 11 of the cylinder hydrogen engine fully exerts the fuel-saving potential of the exhaust gas recirculation system; at the same time, the exhaust gas recirculation system of the present invention is provided with the warm-up exhaust tail pipeline 3 and the energy recovery exhaust The gas tail pipe 4 uses the heat of the exhaust gas to heat and generate electricity for the engine oil in the oil pan 5, realizing rapid heating and energy recovery of the engine oil, which is conducive to the popularization and application of hybrid power, and can improve the power and economy of the engine sex.

Specifically, the engine used in the exhaust gas recirculation system of the present invention is a three-cylinder hydrogen engine. Since the product of hydrogen combustion is only water, it will not pollute the environment. Therefore, hydrogen energy, as one of the representatives of future clean energy, can further solve the problem of Emission pollution from passenger cars.

The engine oil heating device 31 of the present invention includes an engine oil heat exchanger, and the engine oil heat exchanger is used for exchanging heat between the exhaust gas flowing through the engine oil heat exchanger itself and the engine oil in the oil pan 5, so as to heat the engine oil, and heat the engine oil The exhaust gas flowing out of the device 31 will be discharged to the outside through the exhaust tailpipe 13 .

Specifically, in the cold start stage of the car, since the water temperature in the engine is much lower than the temperature (90°C) during normal operation, the fuel consumption and emissions of the engine are relatively poor during the slow heating process. Therefore, the exhaust gas recirculation of the present invention The system heats the engine oil through the engine oil heating device 31, which can shorten the engine warm-up time, realize rapid warm-up, significantly reduce the fuel consumption rate of the engine, and improve the emission of harmful pollutants.

The power generating device 42 of the present invention includes a thermoelectric generator, and the exhaust gas in the energy recovery exhaust tail pipeline 4 will exchange heat with the thermoelectric generator when passing through the exhaust gas storage tank 41, and the thermoelectric generator converts the heat of the exhaust gas into electrical energy for Power generation realizes the energy recovery of exhaust gas, and the exhaust gas flowing out from the exhaust gas storage tank 41 will be discharged to the outside through the exhaust tail pipe 13 .

Optionally, the thermoelectric generator can be arranged inside the exhaust gas storage tank 41 or outside the exhaust gas storage tank 41 , as long as it can exchange heat with the exhaust gas in the exhaust gas storage tank 41 .

In the embodiment shown in FIG. 1 of the present invention, the thermoelectric generator is arranged in the exhaust gas storage tank 41 for exchanging heat with the exhaust gas in the exhaust gas storage tank 41 .

In an unillustrated embodiment of the present invention, the thermoelectric generator is arranged outside the exhaust gas storage tank 41 for exchanging heat with the exhaust gas in the exhaust gas storage tank 41 through the exhaust gas storage tank 41 .

As shown in Figure 1, a total flow sensor 22 is arranged on the exhaust gas recovery pipeline 2 to detect the total flow of gas in the exhaust gas recovery pipeline 2; wherein, the total flow sensor 22 is arranged near the exhaust gas recovery device 21 One side of the exhaust port of the cylinder 11 connected to it; and/or the exhaust gas recovery pipeline 2 is provided with a master valve 23, so as to control the on-off of the corresponding exhaust gas recovery pipeline 2 through the master valve 23; wherein, the master valve 23 is arranged on the side of the exhaust gas recovery device 21 close to the exhaust port of the cylinder 11 connected thereto; and/or the multiple cylinders 11 include a first cylinder 111, a second cylinder 112 and a third cylinder 113, the first cylinder 111, The exhaust port of one of the second cylinder 112 and the third cylinder 113 is connected to the exhaust gas recovery pipeline 2, and the exhaust ports of the other two of the first cylinder 111, the second cylinder 112 and the third cylinder 113 are all connected to the exhaust gas recovery pipeline 2. Gas device 12 is connected.

In the embodiment shown in FIG. 1 of the present invention, the waste gas recovery pipeline 2 includes a waste gas recovery main pipeline, the inlet of the waste gas recovery main pipeline is connected with the exhaust port of the first cylinder 111, and the outlet of the waste gas recovery main pipeline is connected to the waste gas recovery The inlet of the device 21 is connected, the total flow sensor 22 and the total valve 23 are arranged on the exhaust gas recovery main pipeline, and the total flow sensor 22 is located on the side of the total valve 23 away from the exhaust gas recovery device 21 .

As shown in Figure 1, the exhaust gas recovery pipeline 2 includes a plurality of intake sub-pipelines 24, the outlets of the plurality of intake sub-pipelines 24 are connected to the intake ports of the plurality of cylinders 11 in a one-to-one correspondence, each intake sub-pipeline 24 The inlets of each are connected to the outlet of the waste gas recovery device 21.

In the embodiment shown in FIG. 1 of the present invention, a plurality of air intake sub-pipelines 24 include a first air intake sub-pipeline 241, the inlet of the first air intake sub-pipeline 241 is connected to the outlet of the exhaust gas recovery device 21, and the first inlet The outlet of the air distribution pipeline 241 is connected with the intake port of the first cylinder 111 .

In the embodiment shown in FIG. 1 of the present invention, a plurality of air intake sub-pipelines 24 include a second air intake sub-pipeline 242, the inlet of the second air intake sub-pipeline 242 is connected to the outlet of the exhaust gas recovery device 21, and the second inlet The outlet of the air distribution pipeline 242 is connected with the intake port of the second cylinder 112 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of air intake sub-pipelines 24 include a third air intake sub-pipeline 243, the inlet of the third air intake sub-pipeline 243 is connected to the outlet of the exhaust gas recovery device 21, and the third inlet The outlet of the gas distribution pipeline 243 is connected with the intake port of the third cylinder 113 .

As shown in Figure 1, each intake sub-pipeline 24 is provided with a sub-pipeline flow sensor 25, and the sub-pipeline flow sensor 25 is used to detect the flow rate of the gas in the corresponding intake sub-pipeline 24; and/or each intake sub-pipeline 24 is provided with an intake valve 26 to control the on-off of the corresponding intake sub-pipeline 24 and the flow of gas in the corresponding intake sub-pipeline 24 through the intake valve 26 .

In the embodiment shown in FIG. 1 of the present invention, the first intake sub-pipeline 241 is provided with a first sub-pipe flow sensor 251, and the first sub-pipeline flow sensor 251 is used to detect the flow rate in the first intake sub-pipeline 241. gas flow.

In the embodiment shown in FIG. 1 of the present invention, the second intake sub-pipeline 242 is provided with a second sub-pipeline flow sensor 252, and the second sub-pipeline flow sensor 252 is used to detect gas flow.

In the embodiment shown in FIG. 1 of the present invention, the third intake sub-pipeline 243 is provided with a third sub-pipeline flow sensor 253, and the third sub-pipeline flow sensor 253 is used to detect the flow rate in the third intake sub-pipeline 243. gas flow.

In the embodiment shown in FIG. 1 of the present invention, a first air intake valve 261 is arranged on the first air intake sub-pipeline 241, so as to control the flow of the corresponding first air intake sub-pipeline 241 through the first air intake valve 261. On-off and through the first intake valve 261 to control the flow of gas in the corresponding first intake sub-pipeline 241; wherein, the first intake valve 261 is located near the exhaust gas recovery device 21 of the first sub-pipeline flow sensor 251 side.

In the embodiment shown in FIG. 1 of the present invention, a second air intake valve 262 is provided on the second air intake sub-pipeline 242 to control the flow of the corresponding second air intake sub-pipeline 242 through the second air intake valve 262 . On-off and through the second intake valve 262 to control the flow of gas in the corresponding second intake sub-pipeline 242; wherein, the second intake valve 262 is located near the exhaust gas recovery device 21 of the second sub-pipeline flow sensor 252 side.

In the embodiment shown in FIG. 1 of the present invention, a third air intake valve 263 is provided on the third air intake sub-pipeline 243 to control the flow of the corresponding third air intake sub-pipeline 243 through the third air intake valve 263 . On-off and through the third intake valve 263 to control the flow of gas in the corresponding third intake sub-pipe 243; wherein, the third intake valve 263 is located near the exhaust gas recovery device 21 of the third sub-pipe flow sensor 253 side.

As shown in Figure 1, the intake and exhaust assembly 1 includes an intake device 14 and a plurality of intake manifolds 15, the inlets of the plurality of intake manifolds 15 are connected with the outlets of the intake device 14, and the plurality of intake manifolds The outlet of 15 is connected with the intake port of a plurality of cylinders 11 in one-to-one correspondence; The exhaust ports are connected in one-to-one correspondence, and the outlet of one of the plurality of exhaust manifolds 17 is connected with the inlet of the exhaust gas recovery pipeline 2, and the outlets of the remaining exhaust manifolds 17 in the plurality of exhaust manifolds 17 are all It is connected to the inlet of the exhaust device 12 .

As shown in FIG. 1 , the air intake and exhaust assembly 1 further includes an air filter 16 , which is connected to the inlet of the air intake device 14 to filter the fresh air outside before entering the air intake device 14 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of intake manifolds 15 include a first intake manifold 151 , and the inlet of the first intake manifold 151 is connected to the outlet of the first intake manifold 241 , The outlet of the first intake manifold 151 is connected to the intake port of the first cylinder 111 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of intake manifolds 15 include a second intake manifold 152 , the inlet of the second intake manifold 152 is connected to the outlet of the second intake branch line 242 , The outlet of the second intake manifold 152 is connected to the intake port of the second cylinder 112 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of intake manifolds 15 include a third intake manifold 153, the inlet of the third intake manifold 153 is connected with the outlet of the third intake manifold 243, The outlet of the third intake manifold 153 is connected with the intake port of the third cylinder 113 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of exhaust manifolds 17 include a first exhaust manifold 171, the inlet of the first exhaust manifold 171 is connected with the exhaust port of the first cylinder 111, and the first exhaust manifold 171 is connected to the exhaust port of the first cylinder 111. The outlet of an exhaust manifold 171 is connected with the inlet of the exhaust gas recovery pipeline 2 .

In the embodiment of the present invention shown in FIG. 1, the plurality of exhaust manifolds 17 include a second exhaust manifold 172, the inlet of the second exhaust manifold 172 is connected to the exhaust port of the second cylinder 112, and the second The outlets of the two exhaust manifolds 172 are connected to the inlets of the exhaust device 12 .

In the embodiment shown in FIG. 1 of the present invention, the plurality of exhaust manifolds 17 include a third exhaust manifold 173, the inlet of the third exhaust manifold 173 is connected with the exhaust port of the third cylinder 113, and the third exhaust manifold 173 is connected to the exhaust port of the third cylinder 113. The outlet of the triple exhaust manifold 173 is connected to the inlet of the exhaust device 12 .

As shown in Figure 1, an oil temperature sensor 32 is arranged in the oil pan 5 to detect the temperature of the oil in the oil pan 5; and/or an oil heating valve 33 is arranged on the warm-up exhaust tail pipeline 3 , to control the on-off of the warm-up exhaust tail pipe 3 through the oil heating valve 33, wherein the oil heating valve 33 is arranged on the side of the oil heating device 31 close to the exhaust device 12; and/or the energy recovery exhaust The tailpipe 4 is provided with an energy recovery valve 43 to control the on-off of the energy recovery exhaust tailpipe 4 through the energy recovery valve 43, wherein the energy recovery valve 43 is arranged near the exhaust device 12 of the exhaust gas storage tank 41 and/or the generating device 42 is used to connect with the storage battery 6 to supply power to the storage battery 6 .

Example 2

As shown in Figures 2 to 4, the present invention provides an exhaust gas recirculation control method, the exhaust gas recirculation control method is used to control the exhaust gas recirculation system in the above-mentioned embodiment 1; the exhaust gas recirculation control method includes: when the engine is in In the working state, the main valve 23 of the exhaust gas recovery pipeline 2 is always opened; the exhaust gas recirculation rate of each cylinder 11 is adjusted by controlling the flow of gas flowing from the exhaust gas recovery pipeline 2 to the intake port of each cylinder 11 .

In this way, the EGR control method of the present invention can adjust the ratio of exhaust gas and fresh air entering each cylinder 11 in real time according to the operating conditions of the engine during the actual driving of the vehicle, so as to adjust the EGR rate of each cylinder 11 ( That is, the EGR rate), reduce the unevenness of the EGR rate in each cylinder 11, so as to achieve the optimal matching in terms of economy, fully tap the fuel-saving potential of the exhaust gas recirculation system, and break the exhaust gas recirculation in the prior art The upper limit of the EGR rate of the system.

The above-mentioned exhaust gas recirculation rate, that is, the EGR rate, is specifically the ratio of the amount of recirculated exhaust gas entering the cylinder to the total amount of gas entering the cylinder. A reasonable control of the EGR rate can affect the purification effect of nitrogen oxides and the emission of the whole machine. It is extremely important that the EGR rate needs to be quantified during the calibration test to judge the impact of the exhaust gas recirculation system on the engine performance.

As shown in Figure 2, the exhaust gas recirculation control method of the present invention adopts PID controller (proportional-integral-differential controller, is made up of proportional unit (P), integral unit (I) and differential unit (D)) to control The exhaust gas recovery pipeline 2 flows to the gas flow in the intake port of each cylinder 11. The PID controller is used as a feedback loop component, which is mainly suitable for systems that are basically linear and whose dynamic characteristics do not change with time. By setting K _p , K _i and the reference value of the three parameters of K _d , and compare the collected data with a reference value, and then use this difference to calculate a new input value, so that the data of the system reaches or remains at the reference value. In this way, adjusting the input value according to the historical data and the occurrence rate of the difference can make the system more accurate and stable, and the PID controller can maintain the stability of the system when other control methods will cause the system to have stability errors or the process is repeated. .

The PID controller of the present invention is based on the real-time air-fuel ratio in the first cylinder 111 and according to the detected air-fuel ratio in the first intake branch pipeline 241 fed back by the first branch pipeline flow sensor 251 on the first intake branch pipeline 241 Through the first intake valve 261 on the first intake sub-pipeline 241 to control the flow of the exhaust gas in the corresponding first intake sub-pipeline 241 to control the flow of the exhaust gas entering the intake port of the first cylinder 111 The flow rate of the exhaust gas can be precisely controlled to precisely control the ratio of the exhaust gas and the fresh air entering the first cylinder 111, so that the real-time EGR rate of the first cylinder 111 can reach the target EGR rate.

The PID controller of the present invention is based on the real-time air-fuel ratio in the second cylinder 112 and the detected flow rate in the second intake sub-pipeline 242 fed back by the second sub-pipeline flow sensor 252 on the second intake sub-pipeline 242 . The flow rate of the gas is controlled by the second intake valve 262 on the second intake sub-pipeline 242 to control the flow rate of the exhaust gas in the corresponding second intake sub-pipeline 242 to control the exhaust gas entering the intake port of the second cylinder 112 The flow of exhaust gas, so as to accurately control the ratio of exhaust gas and fresh air entering the second cylinder 112, so that the real-time EGR rate of the second cylinder 112 reaches the target EGR rate.

The PID controller of the present invention is based on the real-time air-fuel ratio in the third cylinder 113 and the detected air-fuel ratio in the third intake sub-pipeline 243 fed back by the third sub-pipeline flow sensor 253 on the third intake sub-pipeline 243 . The flow rate of the gas is controlled by the third intake valve 263 on the third intake sub-pipeline 243 to control the flow rate of the exhaust gas in the corresponding third intake sub-pipeline 243 to control the exhaust gas entering the intake port of the third cylinder 113 The flow rate of exhaust gas, so as to accurately control the ratio of exhaust gas and fresh air entering the third cylinder 113, so that the real-time EGR rate of the third cylinder 113 reaches the target EGR rate.

As shown in Figures 2 and 4, when the engine is in working condition, the exhaust gas recirculation control method further includes: when the real-time temperature T of the engine oil is lower than the preset temperature _T0 , controlling the warm-up exhaust tail pipe 3 to communicate, and Control the disconnection of the energy recovery exhaust tail pipeline 4 to heat the engine oil through the oil heating device 31; when the real-time temperature T of the engine oil is greater than or equal to the preset temperature _T0 , the control warm-up exhaust tail pipeline 3 is disconnected , and control the communication of the energy recovery exhaust tail pipe 4 to generate electricity through the power generation device 42 .

Specifically, when the engine is in the working state, the EGR control method includes: judging whether the real-time temperature T of the engine oil is greater than or equal to the preset temperature T ₀ according to the detection result of the engine oil temperature sensor 32 .

When the real-time temperature T of the engine oil is less than the preset temperature _T0 , the engine oil heating valve 33 on the warm-up exhaust tail pipeline 3 is used to control the connection of the warm-up exhaust tail pipeline 3, and the energy recovery exhaust tail pipeline 4 on the energy recovery valve 43 to control the energy recovery exhaust tail pipe 4 disconnection, thereby through the oil heating device 31 to heat the oil.

When the real-time temperature T of the engine oil is greater than or equal to the preset temperature _T0 , the engine oil heating valve 33 on the warm-up exhaust tail pipeline 3 is used to control the disconnection of the warm-up exhaust tail pipeline 3, and exhaust gas through energy recovery. The energy recovery valve 43 on the tail pipe 4 controls the communication of the energy recovery exhaust tail pipe 4 to generate electricity through the power generation device 42, and the machine oil is no longer heated by the machine oil heating device 31, so as to avoid the oil in the engine from being heated. Temperature is too high.

Example 3

The present invention provides an engine, including the exhaust gas recirculation system in Embodiment 1 above.

Specifically, the engine of the present invention is a three-cylinder hydrogen engine.

Example 4

The present invention also provides a vehicle including the engine in Embodiment 3 above.

From the above description, it can be seen that the above-mentioned embodiments of the present invention have achieved the following technical effects:

The exhaust gas recirculation system of the present invention includes: an intake and exhaust assembly 1, including a plurality of cylinders 11, an exhaust device 12 and an exhaust tailpipe 13; an exhaust gas recovery pipeline 2, and an exhaust gas recovery device 21 is arranged on the exhaust gas recovery pipeline 2 , the exhaust port of one of the plurality of cylinders 11 is connected to the inlet of the exhaust gas recovery pipeline 2, the outlet of the exhaust gas recovery pipeline 2 is connected to the intake port of each cylinder 11, and the remaining cylinders 11 in the plurality of cylinders 11 The exhaust outlets are all connected to the exhaust tail pipe 13 through the exhaust device 12; the warm-up exhaust tail pipe 3 is located between the exhaust device 12 and the exhaust tail pipe 13, on the warm-up exhaust tail pipe 3 An oil heating device 31 for heat exchange with the oil in the oil pan 5 is provided; the energy recovery exhaust tail pipe 4 is located between the exhaust device 12 and the exhaust tail pipe 13, and the energy recovery exhaust tail pipe 4 is provided with an exhaust gas storage tank 41 and a power generation device 42, and the power generation device 42 is used to convert the energy of the exhaust gas in the exhaust gas storage tank 41 into electrical energy. The exhaust gas recirculation system of the present invention can make full use of the high exhaust energy of the three-cylinder hydrogen engine to increase the EGR rate by connecting the exhaust port of one of the multiple cylinders 11 with the inlet of the exhaust gas recovery pipeline 2 to solve the current problem. In the EGR system in the prior art, the EGR rate of each cylinder is relatively low, and the exhaust gas recirculation system of the present invention can control the EGR rate of each cylinder 11 by controlling the flow rate of the exhaust gas flowing into each cylinder 11, so as to solve the three problems The EGR rate unevenness of each cylinder 11 of the cylinder hydrogen engine fully exerts the fuel-saving potential of the exhaust gas recirculation system; at the same time, the exhaust gas recirculation system of the present invention is provided with the warm-up exhaust tail pipeline 3 and the energy recovery exhaust The gas tail pipe 4 uses the heat of the exhaust gas to heat and generate electricity for the engine oil in the oil pan 5, realizing rapid heating and energy recovery of the engine oil, which is conducive to the popularization and application of hybrid power, and can improve the power and economy of the engine sex.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

The relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. At the same time, it should be understood that, for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the Authorized Specification. In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other examples of the exemplary embodiment may have different values. It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

In the description of the present application, it should be understood that orientation words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" etc. indicate the orientation Or positional relationship is generally based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description. In the absence of a contrary statement, these orientation words do not indicate or imply the device or element referred to It must have a specific orientation or be constructed and operated in a specific orientation, so it should not be construed as limiting the protection scope of the present application; the orientation words "inner and outer" refer to the inner and outer relative to the outline of each component itself.

For the convenience of description, spatially relative terms may be used here, such as "on ...", "over ...", "on the surface of ...", "above", etc., to describe the The spatial positional relationship between one device or feature shown and other devices or features. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

For example, if the device in the figures is turned over, devices described as "above" or "above" other devices or configurations would then be oriented "beneath" or "above" the other devices or configurations. under other devices or configurations". Thus, the exemplary term "above" can encompass both an orientation of "above" and "beneath". The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "installation", "connection", etc. should be understood in a broad sense, such as "connection", which can be a fixed connection , can also be detachably connected, or integrally connected; can be mechanically connected, can also be electrically connected; can be directly connected, can also be indirectly connected through an intermediary, and can be internal communication between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing corresponding components. To limit the protection scope of this application.

The above-described embodiments only express several implementations of the present invention, and its description is more specific and detailed. The present invention specifies the structure and method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed methods. However, it should not be understood as a limitation on the scope of the invention patent, that is, it does not mean that the present invention must rely on the above-mentioned detailed methods to implement.

It should be pointed out that, for those of ordinary skill in the art, without departing from the inventive concept, all other embodiments obtained by those of ordinary skill in the art without creative work, including some Variations and improvements, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. An exhaust gas recirculation system, comprising: An intake and exhaust assembly (1), comprising a plurality of cylinders (11), an exhaust device (12) and an exhaust tailpipe (13); An exhaust gas recovery pipeline (2), the exhaust gas recovery pipeline (2) is provided with an exhaust gas recovery device (21), and the exhaust port of one of the plurality of cylinders (11) is connected to the exhaust gas recovery pipeline ( 2), the outlet of the exhaust gas recovery pipeline (2) is connected to the air inlet of each cylinder (11), and the remaining cylinders (11) in the plurality of cylinders (11) The exhaust outlets of each are connected with the exhaust tailpipe (13) by the exhaust device (12); The warm-up exhaust tail pipe (3) is located between the exhaust device (12) and the exhaust tail pipe (13), and the warm-up exhaust tail pipe (3) is provided with An oil heating device (31) for heat exchange of the oil in the oil pan (5); The energy recovery exhaust tail pipe (4) is located between the exhaust device (12) and the exhaust tail pipe (13), and the energy recovery exhaust tail pipe (4) is provided with an exhaust gas storage A tank (41) and a power generating device (42), the power generating device (42) is used for converting the energy of the exhaust gas in the exhaust gas storage tank (41) into electric energy. 2. The exhaust gas recirculation system according to claim 1, characterized in that, A total flow sensor (22) is arranged on the waste gas recovery pipeline (2) for detecting the total flow of gas in the waste gas recovery pipeline (2); wherein, the total flow sensor (22) set on the side of the exhaust gas recovery device (21) close to the exhaust port of the cylinder (11) connected thereto; and/or The exhaust gas recovery pipeline (2) is provided with a master valve (23), so as to control the on-off of the corresponding exhaust gas recovery pipeline (2) through the master valve (23); wherein, the master valve (23) arranged on the side of the exhaust gas recovery device (21) close to the exhaust port of the cylinder (11) connected thereto; and/or The plurality of cylinders (11) include a first cylinder (111), a second cylinder (112) and a third cylinder (113), the first cylinder (111), the second cylinder (112) and the The exhaust port of one of the third cylinders (113) is connected to the exhaust gas recovery pipeline (2), and the first cylinder (111), the second cylinder (112) and the third cylinder (113 ) in the other two exhaust outlets are all connected with the exhaust device (12). 3. The exhaust gas recirculation system according to claim 1, characterized in that, the exhaust gas recovery pipeline (2) comprises a plurality of intake sub-pipelines (24), and the plurality of intake sub-pipelines (24) The outlets are connected to the intake ports of the plurality of cylinders (11) in one-to-one correspondence, and the inlets of each of the intake sub-pipelines (24) are connected to the exhaust gas recovery device (21). 4. The exhaust gas recirculation system according to claim 3, characterized in that, Each intake sub-pipeline (24) is provided with a sub-pipeline flow sensor (25) for detecting the flow rate of the gas in the corresponding said intake sub-pipeline (24); and/or Each of the intake sub-pipelines (24) is provided with an intake valve (26), so as to control the on-off of the corresponding intake sub-pipeline (24) and the corresponding intake valves (26). The flow rate of the gas in the air inlet sub-pipeline (24). 5. The exhaust gas recirculation system according to claim 1, characterized in that, The intake and exhaust assembly (1) includes an intake device (14) and a plurality of intake manifolds (15), and the inlets of the plurality of intake manifolds (15) are all connected to the intake device (14) The outlets of the plurality of intake manifolds (15) are connected to the intake ports of the plurality of cylinders (11) in a one-to-one correspondence; and/or The intake and exhaust assembly (1) includes a plurality of exhaust manifolds (17), and the inlets of the plurality of exhaust manifolds (17) are in one-to-one correspondence with the exhaust ports of the plurality of cylinders (11). connect. 6. The exhaust gas recirculation system according to claim 1, characterized in that, An oil temperature sensor (32) is arranged in the oil pan (5) for detecting the temperature of the engine oil in the oil pan (5); and/or An oil heating valve (33) is arranged on the warm-up exhaust tail pipe (3), so as to control the on-off of the warm-up exhaust pipe (3) through the oil heating valve (33), Wherein, the oil heating valve (33) is arranged on the side of the oil heating device (31) close to the exhaust device (12); and/or The energy recovery exhaust tail pipeline (4) is provided with an energy recovery valve (43), so as to control the on-off of the energy recovery exhaust tail pipeline (4) through the energy recovery valve (43), Wherein, the energy recovery valve (43) is arranged on a side of the exhaust gas storage tank (41) close to the exhaust device (12); and/or The power generating device (42) is used for connecting with the storage battery (6) to supply power to the storage battery (6). 7. An exhaust gas recirculation control method, characterized in that the exhaust gas recirculation control method is used to control the exhaust gas recirculation system according to any one of claims 1 to 6; the exhaust gas recirculation control method comprises: When the engine is in working condition, always open the main valve (23) of the waste gas recovery pipeline (2); The exhaust gas recirculation rate of each cylinder (11) is adjusted by controlling the flow rate of gas flowing from the exhaust gas recovery pipeline (2) to the intake port of each cylinder (11). 8. The exhaust gas recirculation control method according to claim 7, characterized in that, when the engine is in a working state, the exhaust gas recirculation control method further comprises: When the real-time temperature T of the engine oil is less than the preset temperature _T0 , the warm-up exhaust tail pipe (3) is controlled to be connected, and the energy recovery exhaust tail pipe (4) is controlled to be disconnected to pass The machine oil heating device (31) heats the machine oil; When the real-time temperature T of the engine oil is greater than or equal to the preset temperature _T0 , the warm-up exhaust tail pipe (3) is controlled to be disconnected, and the energy recovery exhaust tail pipe (4) is controlled to be connected, To generate electricity through the power generating device (42). 9. An engine, characterized by comprising the exhaust gas recirculation system according to any one of claims 1-6. 10. A vehicle comprising the engine of claim 9.

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