JP6804345B2 - Supercharging system and internal combustion engine - Google Patents

Description

The present invention relates to a supercharging system that drives a compressor using exhaust gas discharged from an exhaust turbine to supercharge, and an internal combustion engine including this supercharging system.

For example, an internal combustion engine mounted on an automobile is equipped with a supercharger in order to improve fuel efficiency. This supercharger (turbocharger) uses the exhaust gas discharged from the internal combustion engine to drive a turbine and a compressor to compress and supply intake air to the internal combustion engine to improve the output of the internal combustion engine. On the other hand, there is also a supercharger (supercharger) that compresses and supplies intake air to the internal combustion engine by driving a compressor with an electric motor to improve the output of the internal combustion engine.

As such a supercharger, for example, there is one described in Patent Document 1 below. The control device of the turbo compound system described in Patent Document 1 includes a turbocharger and a turbine generator.

JP-A-2015-108330

The control device of the turbo compound system of the conventional internal combustion engine described above includes a turbocharger and a turbine generator. In this case, the turbine generator may deteriorate in performance or be damaged due to its own heat generation. Further, since the turbine generator is directly connected to the turbine driven by the high temperature exhaust gas, the temperature becomes high due to the exhaust heat, and the performance may be deteriorated or damaged.

The present invention solves the above-mentioned problems, and an object of the present invention is to provide a supercharging system and an internal combustion engine for improving reliability and performance.

The supercharging system of the present invention for achieving the above object has a first supercharger having a first compressor and a first turbine, and a second supercharger having a second compressor and a second turbine connected coaxially. A turbocharger, an intake line in which the first compressor and the second compressor are connected in series, an exhaust line in which the first turbine and the second turbine are connected in series, and a shaft of the first compressor. It is characterized by including an electric motor connected to the end and a generator connected to the shaft end of the first turbine.

Therefore, the first supercharger composed of the first compressor having an electric motor and the first turbine having a generator and the second supercharger composed of the second compressor and the second turbine connected coaxially are sucked. By connecting in series with a line and an exhaust line, the operation and stop of the electric motor and the generator can be controlled according to the operating state, and supercharging can be performed by operating only the second supercharger. As a result, the reliability of the first turbocharger can be improved and the performance can be improved.

In the supercharging system of the present invention, in the intake line, the upstream side in the air flow direction is connected to the discharge side of the first compressor, and the downstream side in the air flow direction is connected to the intake side of the second compressor. The exhaust line is characterized in that the upstream side in the exhaust flow direction is connected to the discharge side of the second turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the first turbine.

Therefore, by arranging the first compressor on the upstream side of the intake from the second compressor and the first turbine on the downstream side of the exhaust from the second turbine, the electric motor and the generator are arranged at positions separated from the engine. In particular, the temperature rise of the electric motor and the generator due to the heat of the engine can be suppressed, and the durability of the first supercharger can be improved.

In the supercharging system of the present invention, the upstream side of the intake line in the air flow direction is connected to the discharge side of the second compressor, and the downstream side in the air flow direction is connected to the intake side of the first compressor. The exhaust line is characterized in that the upstream side in the exhaust flow direction is connected to the discharge side of the first turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the second turbine.

Therefore, by arranging the first compressor on the downstream side of the intake air from the second compressor and the first turbine on the upstream side of the exhaust gas from the second turbine, the intake resistance in the second compressor is reduced, which is relatively high. The supply pressure can be secured. In addition, the distance between the first compressor and the engine is shortened, compressed air can be quickly supplied to the engine when supercharging is required, and the occurrence of turbo lag can be suppressed.

In the supercharging system of the present invention, the upstream side of the intake line in the air flow direction is connected to the discharge side of the second compressor, and the downstream side in the air flow direction is connected to the intake side of the first compressor. The exhaust line is characterized in that the upstream side in the exhaust flow direction is connected to the discharge side of the second turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the first turbine.

Therefore, by arranging the first compressor on the downstream side of the intake from the second compressor and the first turbine on the downstream side of the exhaust from the second turbine, the intake resistance in the second compressor is reduced and the intake resistance from the engine is reduced. Since the second turbine is driven directly by the exhaust gas, a high boost pressure can be ensured. In addition, the distance between the first compressor and the engine is shortened, compressed air can be quickly supplied to the engine when supercharging is required, and the occurrence of turbo lag can be suppressed. Further, the generator can be arranged at a position separated from the engine, the temperature rise of the generator due to the heat of the engine can be suppressed, and the durability can be improved.

In the supercharging system of the present invention, in the intake line, the upstream side in the air flow direction is connected to the discharge side of the first compressor, and the downstream side in the air flow direction is connected to the intake side of the second compressor. The exhaust line is characterized in that the upstream side in the exhaust flow direction is connected to the discharge side of the first turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the second turbine.

Therefore, by arranging the first compressor on the upstream side of the intake air from the second compressor and the first turbine on the upstream side of the exhaust gas from the second turbine, the electric motor can be arranged at a position away from the engine. The temperature rise of the electric motor due to the heat of the engine is suppressed, and the durability of the first supercharger can be improved. Further, since the first turbine is directly driven by the exhaust gas from the engine, a high boost pressure can be ensured.

In the supercharging system of the present invention, a bypass intake line for bypassing the first compressor, an intake on-off valve provided for the bypass intake line, a bypass exhaust line for bypassing the first turbine, and a bypass exhaust line are provided. It is characterized in that an exhaust on-off valve is provided.

Therefore, by opening and closing the intake on-off valve and the exhaust on-off valve according to the operating state of the engine, the supercharging efficiency can be improved and the power generation efficiency by the generator can be improved.

In the supercharging system of the present invention, a bypass exhaust line for bypassing the first turbine is provided, and the upstream side of the bypass exhaust line in the exhaust flow direction is connected to the exhaust line in the housing of the second turbine. It is a feature.

Therefore, by connecting the upstream side of the bypass exhaust line to the exhaust line in the housing of the second turbine, the bypass exhaust line can be arranged away from the generator, and the temperature of the generator becomes high due to the heat of the exhaust. It can be suppressed and the durability can be improved.

In the supercharging system of the present invention, a bypass exhaust line for bypassing the first turbine is provided, and the upstream side of the bypass exhaust line in the exhaust flow direction is connected to the exhaust inflow line outside the housing of the first turbine. It is characterized by.

Therefore, by connecting the upstream side of the bypass exhaust line to the exhaust inflow line outside the housing of the first turbine, the bypass exhaust line can be arranged away from the generator, and the temperature of the generator becomes high due to the heat of the exhaust. Can be suppressed and durability can be improved.

The supercharging system of the present invention is characterized in that the operating range of the second compressor is set wider than the operating range of the first compressor.

Therefore, by setting the operating range of the first compressor to be narrow and reducing the capacity, the first compressor need only be driven when necessary according to the engine operating state, and the first compressor can be miniaturized.

The supercharging system of the present invention is characterized in that the volume of the generator is set to be larger than the volume of the electric motor.

Therefore, by setting the volume of the generator to be larger than the volume of the electric motor, the output of the generator becomes larger than the output of the electric motor, and the generated surplus power can be used for other electric equipment and the like.

Further, the internal combustion engine of the present invention is characterized by including the supercharging system.

Therefore, the reliability of the first turbocharger can be improved and the performance can be improved.

According to the supercharging system and the internal combustion engine of the present invention, the reliability of the first supercharger can be improved and the performance can be improved.

FIG. 1 is a schematic configuration diagram showing a supercharging system of the first embodiment. FIG. 2 is a graph showing the operating range of the first supercharger and the second supercharger. FIG. 3 is a schematic configuration diagram showing the supercharging system of the second embodiment. FIG. 4 is a schematic configuration diagram showing the supercharging system of the third embodiment. FIG. 5 is a schematic configuration diagram showing the supercharging system of the fourth embodiment.

Hereinafter, preferred embodiments of the supercharging system and the internal combustion engine according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited to this embodiment, and when there are a plurality of embodiments, the present invention also includes a combination of the respective embodiments.

[First Embodiment]
FIG. 1 is a schematic configuration diagram showing a supercharging system of the first embodiment.

As shown in FIG. 1, in the supercharging system 10 of the first embodiment, although the engine (internal combustion engine) 11 is not shown, a plurality of cylinders are formed in the engine body, and the pistons can be moved up and down in each cylinder. It is supported and each piston has its lower end connected to a crankshaft. In the engine body, a combustion chamber is formed above each cylinder, an intake port and an exhaust port are formed above each combustion chamber, an intake valve is provided at the intake port, and an exhaust valve is provided at the exhaust port. Has been done.

In the engine 11, an intake manifold 12 is mounted on one side of the engine body, and an exhaust manifold 13 is mounted on the other side. The intake manifold 12 communicates with the combustion chamber via each intake port, and the exhaust manifold 13 communicates with the combustion chamber via each exhaust port. In addition, the engine body is provided with injectors that inject fuel into the intake port and the combustion chamber.

The first supercharger 20 is an electric low-pressure supercharger, which has a first compressor 21 and a first turbine 22, and the electric motor 23 is connected to a rotating shaft of the first compressor 21 to form a first turbine. The generator 24 is connected to the rotating shaft of 22. In the first compressor 21, the downstream end of the first intake pipe (air intake line) L1 that sucks air from the outside is connected to the suction side, and the second intake pipe (intake line) that discharges compressed air to the discharge side. ) The upstream end of L2 is connected. In the first turbine 22, the downstream end of the first exhaust pipe (exhaust line) L3 is connected to the inflow side, and the exhaust gas is discharged to the outside on the upstream side of the second exhaust pipe (exhaust discharge line) L4. The ends are connected.

Further, in the bypass intake pipe (bypass intake line) L5 that bypasses the first compressor 21, the base end portion on the upstream side in the air flow direction is connected to the first intake pipe L1 and the tip on the downstream side in the air flow direction. The portion is connected to the second intake pipe L2. In the bypass exhaust pipe (bypass exhaust line) L6 that bypasses the first turbine 22, the base end on the upstream side in the exhaust flow direction is connected to the first exhaust pipe L3, and the tip on the downstream side in the exhaust flow direction is connected. It is connected to the second exhaust pipe L4. The bypass intake pipe L5 is provided with an intake on-off valve 41, and the bypass exhaust pipe L6 is provided with an exhaust on-off valve 42. The intake on-off valve 41 and the exhaust on-off valve 42 are an on-off valve that stops at the fully open position and the fully closed position, or a flow rate adjusting valve whose opening can be adjusted.

The second supercharger 30 is an exhaust type high-pressure supercharger, in which the second compressor 31 and the second turbine 32 are coaxially connected via a rotating shaft 33, and the second compressor 31 is configured. And the second turbine 32 can be integrally rotated by the rotating shaft 33. The second compressor 31 is connected to the downstream end of the first intake pipe L1 to which compressed air is supplied from the first compressor 21 of the first supercharger 20 to the intake side, and the intake manifold 12 of the engine 11 is connected to the discharge side. The upstream end of the third intake pipe (air discharge line) L7 leading to the above is connected. In the second turbine 32, the downstream end of the third exhaust pipe (exhaust inflow line) L8 leading to the exhaust manifold 13 of the engine 11 is connected to the inflow side, and the first turbine 22 of the first supercharger 20 is connected to the exhaust side. The upstream end of the first exhaust pipe L3 that supplies exhaust gas to the engine is connected. The third intake pipe L7 is provided with an intercooler 43.

Further, the electric motor 23 and the generator 24 are connected to AC / DC / AC converters (hereinafter referred to as converters) 25 and 26, respectively, and a capacitor (battery) 27 is connected to the converters 25 and 26, respectively. .. In this case, the electric motor 23 and the generator 24 may be provided with a shared converter or a dedicated capacitor for each.

In this case, in the first supercharger 20, the first compressor 21 and the electric motor 23 are housed in the compressor housing 51, and the first turbine 22 and the generator 24 are housed in the turbine housing 52. Further, in the second supercharger 30, the second compressor 31, the second turbine 32, and the rotating shaft 33 are housed in the supercharger housing 53.

Then, in the first compressor 21, the first intake pipe L1 and the second intake pipe L2 are connected to the suction portion and the discharge portion of the compressor housing 51, respectively. The base end of the bypass intake pipe L5 is connected to the first intake pipe L1 outside (or inside) the compressor housing 51, and the tip end is inside the supercharger housing 53 and is the suction part of the second compressor 31 or , It is connected to the connecting portion of the second intake pipe L2 in the supercharger housing 53. Further, in the first turbine 22, the first exhaust pipe L3 and the second exhaust pipe L4 are connected to the inflow portion and the discharge portion of the turbine housing 52, respectively. The base end of the bypass exhaust pipe L6 is connected to the discharge portion of the second turbine 32 or the connecting portion of the first exhaust pipe L3 inside the supercharger housing 53, and the tip end portion is connected to the outside (or or) of the turbine housing 52. , Inside) is connected to the second exhaust pipe L4.

Therefore, in the first supercharger 20, when the first compressor 21 is driven and rotated by the electric motor 23, the air sucked from the first intake pipe L1 is compressed, and then the compressed air is supplied from the second intake pipe L2 to the second supercharger 20. It can be supplied from the intake manifold 12 to the combustion chamber of the engine 11 through the second compressor 31 of the machine 30. The engine 11 discharges exhaust gas (combustion gas) to the exhaust manifold 13, and the second supercharger 30 is driven and rotated by the exhaust gas supplied by the second turbine 32 from the exhaust manifold 13 through the third exhaust pipe L8. Then, the second compressor 31 is driven and rotated. The second compressor 31 further compresses the compressed air from the first supercharger 20 by driving and rotating, and supplies the compressed air from the third intake pipe L7 to the combustion chamber of the engine 11 through the intake manifold 12. it can. In the first supercharger 20, the first turbine 22 can be driven and rotated by the exhaust gas supplied from the second turbine 32 through the first exhaust pipe L3 to drive the generator 24. The exhaust gas that has passed through the first turbine 22 is discharged to the outside from the second exhaust pipe L4.

At this time, the capacitor 27 can convert the stored electric power by the converter 25 and supply it to the electric motor 23, and the electric motor 23 can be driven. Further, the capacitor 27 can convert the electric power generated by the generator 24 by the converter 26 and store the electric power. Further, when the intake on-off valve 41 is opened, the bypass intake pipe L5 can bypass the first compressor 21 of the first supercharger 20 and directly take in air to the second compressor 31 of the second supercharger 30. Further, when the exhaust on-off valve 42 is opened, the bypass exhaust pipe L6 bypasses the first turbine 22 of the first supercharger 20 and directly discharges the exhaust gas from the second turbine 32 of the second supercharger 30. it can. A control device (not shown) can control the opening and closing of the intake on-off valve 41 and the exhaust on-off valve 42 according to the operating state (load, rotation speed, etc.) of the engine 11.

Further, the first turbocharger 20 is an electric low-pressure turbocharger, and the second supercharger 30 is an exhaust-type high-pressure turbocharger. FIG. 2 is a graph showing the operating range of the first supercharger and the second supercharger. As shown in FIG. 2, the operating range of the first compressor 31 is set wider than the operating range of the first compressor 21. That is, when comparing the pressure ratios to the flow rates of the first compressor 21 and the second compressor 31, the second compressor 31 has a large flow rate and a high pressure ratio operating range A2 is set, and the first compressor 21 has a small flow rate and a low pressure ratio. The operating range A1 of the pressure ratio is set. Specifically, the blade diameter, suction port area, discharge port area, etc. of the compressor are set smaller in the first compressor 21 than in the second compressor 31.

Here, the operation of the supercharging system 10 of the first embodiment will be described.

In the supercharging system 10 of the present embodiment, as shown in FIG. 1, when the engine 11 starts and the required load of the engine 11 rises, the intake on-off valve 41 is closed while the exhaust on-off valve 42 is opened. 1 The electric motor 23 of the supercharger 20 is driven to drive and rotate the first compressor 21. Then, the first compressor 21 is driven and rotated by the electric motor 23 to suck air from the first intake pipe L1, and after the first compressor 21 compresses the air, the compressed air is second from the second intake pipe L2. It is supplied from the intake manifold 12 to the combustion chamber of the engine 11 through the second compressor 31 of the supercharger 30. The engine 11 is driven by igniting and burning a mixture of fuel and compressed air in each combustion chamber, and exhaust gas is discharged to the exhaust manifold 13. The exhaust gas discharged from the exhaust manifold 13 to the third exhaust pipe L8 drives and rotates the second turbine 32 of the second supercharger 30, and drives and rotates the second compressor 31. When the second compressor 31 is driven and rotated, the compressed air from the first supercharger 20 is further compressed, and the compressed air is supplied from the third intake pipe L7 to the combustion chamber of the engine 11 through the intake manifold 12. The exhaust gas that has been driven and rotated by the second turbine 32 is exhausted from the first exhaust pipe L3 to the second exhaust pipe L4 mainly through the bypass exhaust pipe L6, and is discharged to the outside. Therefore, when the engine 11 is started, the rotation of the first turbine 22 of the first supercharger 20 is stopped.

At this time, as the rotation speed of the electric motor 23 increases, the rotation speed of the first compressor 21 increases, and the intake amount and the exhaust gas amount increase, so that the rotation speed of the second supercharger 30 gradually increases. .. After that, when the rotation speed of the first compressor 21 of the first supercharger 20 becomes constant and the engine load reaches a predetermined value, the driving of the electric motor 23 is stopped and the rotation of the first compressor 21 is stopped. Here, by opening the intake on-off valve 41, the second compressor 31 of the second supercharger 30 sucks air through the bypass intake pipe L5, and only the second compressor 31 drives to compress the air. It becomes.

When the engine load is preset and exceeds a predetermined value, the exhaust on-off valve 42 is closed, and the exhaust gas from the second turbine 32 is introduced into the first turbine 22 through the first exhaust pipe L3. Then, the first turbine 22 is driven and rotated by this exhaust gas, and the generator 24 starts the drive rotation to generate electricity. After that, when the required load of the engine 11 decreases, the amount of exhaust gas from the engine 11 decreases, the rotation speeds of the first turbine 22 and the second supercharger 30 decrease, and the engine load also decreases. Then, when the rotation of the generator 24 is stopped, the exhaust on-off valve 42 is opened, and the exhaust gas that drives and rotates the second turbine 32 is discharged from the first exhaust pipe L3 to the outside through the bypass exhaust pipe L6. After that, the engine 11 is stopped.

As described above, in the supercharging system of the first embodiment, the second compressor 31 and the second turbine 32 are coaxially connected to the first supercharger 20 having the first compressor 21 and the first turbine 22. The second supercharger 30 having the above, the second intake pipe L2 for connecting the first compressor 21 and the second compressor 31 in series, and the first exhaust for connecting the first turbine 22 and the second turbine 32 in series. A pipe L3, an electric motor 23 connected to the shaft end of the first compressor 21, and a generator 24 connected to the shaft end of the first turbine 22 are provided.

Therefore, it is composed of a first supercharger 20 composed of a first compressor 21 having an electric motor 23 and a first turbine 22 having a generator 24, and a second compressor 31 and a second turbine 32 connected coaxially. By connecting the second supercharger 30 in series with the second intake pipe L2 and the first exhaust pipe L3, the operation and stop of the electric motor 23 and the generator 24 are controlled according to the operating state of the engine 11. 2 Supercharging can be carried out by operating only the supercharger 30. As a result, the reliability of the first supercharger 20 can be improved and the performance can be improved.

In the supercharging system of the first embodiment, in the second intake pipe L2, the upstream side in the air flow direction is connected to the discharge side of the first compressor 21, and the downstream side in the air flow direction is the intake side of the second compressor 31. In the first exhaust pipe L3, the upstream side in the exhaust flow direction is connected to the discharge side of the second turbine 32, and the downstream side is connected to the inflow side of the first turbine 22. Therefore, by arranging the first compressor 21 on the upstream side of the intake from the second compressor 31 and the first turbine 22 on the downstream side of the exhaust from the second turbine 32, the electric motor 23 and the generator 24 are arranged from the engine 11. It can be arranged at a separated position, and in particular, the temperature rise of the electric motor 23 and the generator 24 due to the heat of the engine 11 can be suppressed, and the durability of the first supercharger 20 can be improved.

In the supercharging system of the first embodiment, a bypass intake pipe L5 for bypassing the first compressor 21, an intake on-off valve 41 provided in the bypass intake pipe L5, a bypass exhaust pipe L6 for bypassing the first turbine 22, and a bypass An exhaust on-off valve 42 provided in the exhaust pipe L6 is provided. Therefore, by opening and closing the intake on-off valve 41 and the exhaust on-off valve 42 according to the operating state of the engine 11, the supercharging efficiency can be improved and the power generation efficiency by the generator 24 can be improved.

In the supercharging system of the first embodiment, the upstream side of the bypass exhaust pipe L6 in the exhaust flow direction is connected to the first exhaust pipe L3 in the supercharger housing 53 of the second turbine 32. Therefore, the bypass exhaust pipe L6 can be arranged apart from the generator 24, the temperature rise of the generator 24 due to the heat of the exhaust can be suppressed, and the durability can be improved.

In the supercharging system of the first embodiment, the operating range of the second compressor 31 is set wider than the operating range of the first compressor 21. Therefore, by setting the operating range of the first compressor 21 to be narrow and reducing the capacity, it is sufficient to drive the first compressor 21 only when necessary according to the engine operating state, and the first compressor 21 can be miniaturized. it can.

Further, the internal combustion engine of the first embodiment includes the above-mentioned supercharging system. Therefore, the reliability of the first turbocharger 20 can be improved, and the performance can be improved.

[Second Embodiment]
FIG. 3 is a schematic configuration diagram showing the supercharging system of the second embodiment. The members having the same functions as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 3, in the supercharging system 10A of the second embodiment, the second supercharger 30 is configured such that the second compressor 31 and the second turbine 32 are coaxially connected via a rotating shaft 33. ing. In the second compressor 31, the downstream end of the first intake pipe L1 that sucks air from the outside is connected to the suction side, and the upstream end of the second intake pipe L2 that discharges compressed air is connected to the discharge side. ing. In the second turbine 32, the downstream end of the first exhaust pipe L3 is connected to the inflow side, and the upstream end of the second exhaust pipe L4 that discharges the exhaust gas to the outside is connected to the discharge side.

The first supercharger 20 has a first compressor 21 and a first turbine 22, an electric motor 23 is connected to the rotating shaft of the first compressor 21, and a generator 24 is connected to the rotating shaft of the first turbine 22. It is composed of. In the first compressor 21, the downstream end of the second intake pipe L2 to which compressed air is supplied from the second compressor 31 of the second supercharger 30 is connected to the intake side, and the intake manifold 12 of the engine 11 is connected to the discharge side. The upstream end of the third intake pipe L7 leading to the above is connected. In the first turbine 22, the downstream end of the third exhaust pipe L8 leading to the exhaust manifold 13 of the engine 11 is connected to the inflow side, and exhaust gas is supplied to the second turbine 32 of the second supercharger 30 on the exhaust side. The upstream end of the first exhaust pipe L3 is connected.

Further, in the bypass intake pipe L5 bypassing the first compressor 21, the base end portion on the upstream side in the air flow direction is connected to the second intake pipe L2, and the tip end portion on the downstream side in the air flow direction is the third intake air. It is connected to the tube L7. In the bypass exhaust pipe L6 bypassing the first turbine 22, the base end on the upstream side in the exhaust flow direction is connected to the third exhaust pipe L8, and the tip on the downstream side in the exhaust flow direction is the first exhaust pipe L3. Is connected to. The bypass intake pipe L5 is provided with an intake on-off valve 41, and the bypass exhaust pipe L6 is provided with an exhaust on-off valve 42.

Further, the electric motor 23 and the generator 24 are connected to the converters 25 and 26, respectively, and the capacitor 27 is connected to the converters 25 and 26, respectively.

In this case, in the first supercharger 20, the first compressor 21 and the electric motor 23 are housed in the compressor housing 51, and the first turbine 22 and the generator 24 are housed in the turbine housing 52. Further, in the second supercharger 30, the second compressor 31, the second turbine 32, and the rotating shaft 33 are housed in the supercharger housing 53.

Then, in the first compressor 21, the base end portion of the bypass intake pipe L5 is connected to the suction portion of the first compressor 21 or the connecting portion of the second intake pipe L2 inside the compressor housing 51, and the tip portion is connected. It is connected to the third intake pipe L7 outside the compressor housing 51. Further, in the first turbine 22, the base end portion of the bypass exhaust pipe L6 is connected to the third exhaust pipe L8 outside the turbine housing 52, and the tip end portion is inside the turbine housing 52 and is the discharge portion of the first turbine 22. , Or, it is connected to the connecting portion of the first exhaust pipe L3.

Therefore, when the first compressor 21 is driven and rotated by the electric motor 23, the first supercharger 20 compresses the air sucked from the first intake pipe L1 and the second intake pipe L2, and then applies the compressed air to the third intake pipe. L7 can supply air from the intake manifold 12 to the combustion chamber of the engine 11. The engine 11 discharges exhaust gas (combustion gas) to the exhaust manifold 13, and in the second supercharger 30, the second turbine 32 is supplied from the exhaust manifold 13 through the third exhaust pipe L8 and the first exhaust pipe L3. It is driven and rotated by the exhaust gas, and the second compressor 31 is driven and rotated. The second compressor 31 can compress the air sucked from the first intake pipe L1 by driving and rotating, and supply the compressed air from the second intake pipe L2 to the first compressor 21. In the first supercharger 20, the first turbine 22 can be driven and rotated by the exhaust gas discharged from the exhaust manifold 13 of the engine 11 to drive the generator 24. The exhaust gas that has passed through the second turbine 32 is discharged to the outside from the second exhaust pipe L4.

At this time, the capacitor 27 can convert the stored electric power by the converter 25 and supply it to the electric motor 23, and the electric motor 23 can be driven. Further, the capacitor 27 can convert the electric power generated by the generator 24 by the converter 26 and store the electric power. Further, when the intake on-off valve 41 is opened, the bypass intake pipe L5 bypasses the first compressor 21 of the first supercharger 20 and the air compressed by the second compressor 31 of the second supercharger 30 is directly sent to the engine 11. Can be supplied. Further, when the exhaust on-off valve 42 is opened, the bypass exhaust pipe L6 bypasses the first turbine 22 of the first supercharger 20 and directly supplies the exhaust gas from the engine 11 to the second turbine 32 of the second supercharger 30. can do.

As described above, in the supercharging system of the second embodiment, in the second intake pipe L2, the upstream side in the air flow direction is connected to the discharge side of the second compressor 31, and the downstream side in the air flow direction is the first. The first exhaust pipe L3 is connected to the intake side of the compressor 21, the upstream side in the exhaust flow direction is connected to the discharge side of the first turbine 22, and the downstream side is connected to the inflow side of the second turbine 32.

Therefore, by arranging the first compressor 21 on the downstream side of the intake air from the second compressor 31 and arranging the first turbine 22 on the upstream side of the exhaust gas from the second turbine 32, the intake resistance in the second compressor 31 is reduced. , A relatively high boost pressure can be secured. Further, the distance between the first compressor 21 and the engine 11 is shortened, and when supercharging is required, the first compressor 21 can be driven to quickly supply compressed air to the engine 11 to suppress the occurrence of turbo lag. Can be done.

In the supercharging system of the second embodiment, the upstream side of the bypass exhaust pipe L6 in the exhaust flow direction is connected to the third exhaust pipe L8 outside the turbine housing 52 of the first turbine 22. Therefore, the bypass exhaust pipe L6 can be arranged apart from the generator 24, the temperature rise of the generator 24 due to the heat of the exhaust can be suppressed, and the durability can be improved.

[Third Embodiment]
FIG. 4 is a schematic configuration diagram showing the supercharging system of the third embodiment. The members having the same functions as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 4, in the supercharging system 10B of the third embodiment, the second supercharger 30 is configured such that the second compressor 31 and the second turbine 32 are coaxially connected via a rotating shaft 33. ing. In the second compressor 31, the downstream end of the first intake pipe L1 that sucks air from the outside is connected to the suction side, and the upstream end of the second intake pipe L2 that discharges compressed air is connected to the discharge side. ing. In the second turbine 32, the downstream end of the third exhaust pipe L8 leading to the exhaust manifold 13 of the engine 11 is connected to the inflow side, and exhaust gas is supplied to the second turbine 32 of the second supercharger 30 on the exhaust side. The upstream end of the first exhaust pipe L3 is connected.

The first supercharger 20 has a first compressor 21 and a first turbine 22, an electric motor 23 is connected to the rotating shaft of the first compressor 21, and a generator 24 is connected to the rotating shaft of the first turbine 22. It is composed of. In the first compressor 21, the downstream end of the second intake pipe L2 to which compressed air is supplied from the second compressor 31 of the second supercharger 30 is connected to the intake side, and the intake manifold 12 of the engine 11 is connected to the discharge side. The upstream end of the third intake pipe L7 leading to the above is connected. In the first turbine 22, the downstream end of the first exhaust pipe L3 from the second turbine 32 of the second supercharger 30 is connected to the inflow side, and the second exhaust pipe discharges the exhaust gas to the outside on the discharge side. The upstream end of L4 is connected.

Further, in the bypass intake pipe L5 bypassing the first compressor 21, the base end portion on the upstream side in the air flow direction is connected to the second intake pipe L2, and the tip end portion on the downstream side in the air flow direction is the third intake air. It is connected to the tube L7. In the bypass exhaust pipe L6 bypassing the first turbine 22, the base end on the upstream side in the exhaust flow direction is connected to the first exhaust pipe L3, and the tip on the downstream side in the exhaust flow direction is the second exhaust pipe L4. Is connected to. The bypass intake pipe L5 is provided with an intake on-off valve 41, and the bypass exhaust pipe L6 is provided with an exhaust on-off valve 42.

Further, the electric motor 23 and the generator 24 are connected to the converters 25 and 26, respectively, and the capacitor 27 is connected to the converters 25 and 26, respectively.

In this case, in the first supercharger 20, the first compressor 21 and the electric motor 23 are housed in the compressor housing 51, and the first turbine 22 and the generator 24 are housed in the turbine housing 52. Further, in the second supercharger 30, the second compressor 31, the second turbine 32, and the rotating shaft 33 are housed in the supercharger housing 53.

Then, in the first compressor 21, the base end portion of the bypass intake pipe L5 is connected to the suction portion of the second compressor 31 or the connecting portion of the second intake pipe L2 inside the compressor housing 51, and the tip portion is connected. It is connected to the third intake pipe L7 outside the compressor housing 51. Further, in the first turbine 22, the base end portion of the bypass exhaust pipe L6 is connected to the discharge portion of the second turbine 32 or the connecting portion of the first exhaust pipe L3 inside the supercharger housing 53, and the tip end thereof. The portion is connected to the second exhaust pipe L4.

As described above, in the supercharging system of the third embodiment, in the second intake pipe L2, the upstream side in the air flow direction is connected to the discharge side of the second compressor 31, and the downstream side in the air flow direction is the first. The first exhaust pipe L3 is connected to the intake side of the compressor 21, the upstream side in the exhaust flow direction is connected to the discharge side of the second turbine 32, and the downstream side is connected to the inflow side of the first turbine 22.

Therefore, by arranging the first compressor 21 on the downstream side of the intake air from the second compressor 31 and arranging the first turbine 22 on the downstream side of the exhaust gas from the second turbine 32, the intake resistance in the second compressor 31 is reduced. At the same time, since the second turbine 32 is directly driven by the exhaust gas from the engine 11, a high boost pressure can be ensured. Further, the distance between the first compressor 21 and the engine 11 is shortened, and compressed air can be quickly supplied to the engine 11 when supercharging is required, and the occurrence of turbo lag can be suppressed. Further, the generator 24 can be arranged at a position separated from the engine 11, the temperature rise of the generator 24 due to the heat of the engine 11 can be suppressed, and the durability can be improved.

[Fourth Embodiment]
FIG. 5 is a schematic configuration diagram showing the supercharging system of the fourth embodiment. The members having the same functions as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 5, in the supercharging system 10C of the fourth embodiment, the first supercharger 20 has a first compressor 21 and a first turbine 22, and an electric motor 23 is attached to the rotation shaft of the first compressor 21. Is connected, and the generator 24 is connected to the rotating shaft of the first turbine 22. In the first compressor 21, the downstream end of the first intake pipe L1 that sucks air from the outside is connected to the suction side, and the upstream end of the second intake pipe L2 that discharges compressed air is connected to the discharge side. ing. In the first turbine 22, the downstream end of the third exhaust pipe L8 leading to the exhaust manifold 13 of the engine 11 is connected to the inflow side, and exhaust gas is supplied to the second turbine 32 of the second supercharger 30 on the exhaust side. The upstream end of the first exhaust pipe L3 is connected.

The second supercharger 30 is configured such that the second compressor 31 and the second turbine 32 are coaxially connected via a rotating shaft 33. In the second compressor 31, the downstream end of the second intake pipe L2 to which compressed air is supplied from the first compressor 21 of the first supercharger 20 is connected to the intake side, and the intake manifold 12 of the engine 11 is connected to the discharge side. The upstream end of the third intake pipe L7 leading to the above is connected. In the second turbine 32, the downstream end of the first exhaust pipe L3 is connected to the inflow side, and the upstream end of the second exhaust pipe L4 that discharges the exhaust gas to the outside is connected to the discharge side.

Further, in the bypass intake pipe L5 bypassing the first compressor 21, the base end portion on the upstream side in the air flow direction is connected to the first intake pipe L1, and the tip end portion on the downstream side in the air flow direction is the second intake air. It is connected to the tube L2. In the bypass exhaust pipe L6 bypassing the first turbine 22, the base end on the upstream side in the exhaust flow direction is connected to the third exhaust pipe L8, and the tip on the downstream side in the exhaust flow direction is the first exhaust pipe L3. Is connected to. The bypass intake pipe L5 is provided with an intake on-off valve 41, and the bypass exhaust pipe L6 is provided with an exhaust on-off valve 42.

Further, the electric motor 23 and the generator 24 are connected to the converters 25 and 26, respectively, and the capacitor 27 is connected to the converters 25 and 26, respectively.

In this case, in the first supercharger 20, the first compressor 21 and the electric motor 23 are housed in the compressor housing 51, and the first turbine 22 and the generator 24 are housed in the turbine housing 52. Further, in the second supercharger 30, the second compressor 31, the second turbine 32, and the rotating shaft 33 are housed in the supercharger housing 53.

Then, in the first compressor 21, the base end portion of the bypass intake pipe L5 is connected to the first intake pipe L1 outside the compressor housing 51, and the tip end portion is connected to the second intake pipe L2 outside the compressor housing 51. Has been done. Further, in the first turbine 22, the base end portion of the bypass exhaust pipe L6 is connected to the third exhaust pipe L8 outside the turbine housing 52, and the tip end portion is inside the turbine housing 52 and is the discharge portion of the first turbine 22. , Or, it is connected to the connecting portion of the first exhaust pipe L3.

As described above, in the supercharging system of the fourth embodiment, in the second intake pipe L2, the upstream side in the air flow direction is connected to the discharge side of the first compressor 21, and the downstream side in the air flow direction is the second. The first exhaust pipe L3 is connected to the intake side of the compressor 31, the upstream side in the exhaust flow direction is connected to the discharge side of the first turbine 22, and the downstream side is connected to the inflow side of the second turbine 32.

Therefore, by arranging the first compressor 21 on the upstream side of the intake from the second compressor 31 and arranging the first turbine 22 on the upstream side of the exhaust from the second turbine 32, the electric motor 23 is placed at a position separated from the engine 11. It can be arranged, the temperature rise of the electric motor 23 due to the heat of the engine 11 is suppressed, and the durability of the first supercharger 20 can be improved. Further, since the first turbine 22 is directly driven by the exhaust from the engine 11, a high boost pressure can be secured, and the amount of power generated by the generator 24 of the first turbine 22 is the electric motor 23 of the first compressor 21. Since it is larger than the power consumption of, the surplus power can be used for other electric equipment and the like.

In this case, by setting the volume of the generator 24 of the first turbine 22 to be larger than the volume of the electric motor 23 of the first compressor 21, the amount of power generated by the generator 24 can be made larger than the amount of power consumed by the electric motor 23. It is possible to recover more surplus electric power, and it is possible to suppress the heat generation of the generator 24 and improve the efficiency.

In the above-described embodiment, the first supercharger 20 is provided with a bypass intake pipe L5 for the first compressor 21 and a bypass exhaust pipe L6 for the first turbine 22. It may be provided only. Further, a bypass intake pipe may be provided for the second compressor 31 of the second supercharger 30, or a bypass exhaust pipe may be provided for the second turbine 32.

Further, in the above-described embodiment, the first compressor 21 and the second compressor 31 may be provided in parallel on the intake line, or the first turbine 22 and the second turbine 32 may be provided in parallel on the exhaust line.

Further, in the above-described embodiment, the second turbine may be a variable displacement turbo.

10, 10A, 10B, 10C Supercharging system 11 Engine (internal combustion engine)
20 1st turbocharger 21 1st compressor 22 1st turbine 23 Electric motor 24 Generator 25,26 AC / DC / AC converter (converter)
27 Power storage 30 Second supercharger 31 Second compressor 32 Second turbine 33 Rotating shaft 41 Intake on-off valve 42 Exhaust on-off valve 43 Intercooler 51 Compressor housing 52 Turbine housing 53 Supercharger housing L1 First intake pipe (air intake) line)
L2 2nd intake pipe (intake line)
L3 1st exhaust pipe (exhaust line)
L4 2nd exhaust pipe (exhaust exhaust line)
L5 Bypass intake pipe (Bypass intake line)
L6 Bypass exhaust pipe (Bypass exhaust line)
L7 3rd intake pipe (air discharge line)
L8 3rd exhaust pipe (exhaust inflow line)

Claims (6)

A first supercharger having a first compressor and a first turbine,
A second turbocharger having a second compressor and a second turbine coaxially connected,
An intake line in which the first compressor and the second compressor are connected in series,
An exhaust line in which the first turbine and the second turbine are connected in series,
An electric motor connected to the shaft end of the first compressor and
A generator connected to the shaft end of the first turbine and
Bei to give a,
In the intake line, the upstream side in the air flow direction is connected to the discharge side of the first compressor, the downstream side in the air flow direction is connected to the intake side of the second compressor, and the exhaust line is connected to the exhaust flow direction. Is connected to the discharge side of the second turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the first turbine.
A bypass exhaust line for bypassing the first turbine is provided, and the upstream side of the bypass exhaust line in the exhaust flow direction is connected to the exhaust line in the housing of the second turbine.
A supercharging system characterized by that. A first supercharger having a first compressor and a first turbine,
A second turbocharger having a second compressor and a second turbine coaxially connected,
An intake line in which the first compressor and the second compressor are connected in series,
An exhaust line in which the first turbine and the second turbine are connected in series,
An electric motor connected to the shaft end of the first compressor and
A generator connected to the shaft end of the first turbine and
Bei to give a,
In the intake line, the upstream side in the air flow direction is connected to the discharge side of the second compressor, the downstream side in the air flow direction is connected to the intake side of the first compressor, and the exhaust line is connected to the exhaust flow direction. Is connected to the discharge side of the second turbine, and the downstream side in the exhaust flow direction is connected to the inflow side of the first turbine.
A bypass exhaust line for bypassing the first turbine is provided, and the upstream side of the bypass exhaust line in the exhaust flow direction is connected to the exhaust line in the housing of the second turbine.
A supercharging system characterized by that. Wherein a bypass intake line for bypassing the first compressor, according to claim 1 or claim, wherein the intake opening and closing valve provided in the bypass air line, that the previous SL discharge opening and closing valve provided in the bypass exhaust line is provided The supercharging system described in 2 . The supercharging system according to any one of claims 1 to 3 , wherein the operating range of the second compressor is set wider than the operating range of the first compressor. The supercharging system according to claim 3 , further comprising a control device capable of opening and closing the intake on-off valve and the exhaust on-off valve according to the operating state of the internal combustion engine. An internal combustion engine comprising the supercharging system according to any one of claims 1 to 5 .

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