JP-7856072-B2 - Internal combustion engine control device

JP7856072B2JP 7856072 B2JP7856072 B2JP 7856072B2JP-7856072-B2

Inventors

大嶋智也
中川政善

Assignees

トヨタ自動車株式会社

Dates

Publication Date: 20260511
Application Date: 20230907

Claims (4)

An internal combustion engine control device is applied to an internal combustion engine that comprises a cylinder, an intake passage through which air introduced into the cylinder flows, an exhaust passage through which exhaust gas discharged from the cylinder flows, and an EGR device that recirculates a portion of the exhaust gas flowing through the exhaust passage as EGR gas into the intake passage, and gaseous fuel is supplied into the cylinder, The EGR device comprises an EGR passage connected to the intake passage and through which EGR gas flows toward the intake passage, a collection device for collecting condensed water generated in the EGR passage, and an EGR cooler located upstream of the collection device in the EGR passage and for cooling the EGR gas flowing through the EGR passage . The aforementioned collection device, A first passage and a second passage arranged in parallel to each other, A collector placed in the first passage, A switching valve that can adjust the collection efficiency of condensed water by adjusting the distribution ratio of the EGR gas flowing through the first passage, It has the following characteristics: The aforementioned internal combustion engine control device is When EGR gas is introduced into the intake passage via the EGR passage, it is determined whether or not condensation occurs in the confluence portion of the intake passage, which is the part to which the EGR passage is connected. Based on the rotational speed of the output shaft of the internal combustion engine and the output torque of the internal combustion engine, it is determined whether or not the internal combustion engine is operating under high load. An internal combustion engine control device that, when it is determined that condensate is generated in the confluence portion of the intake passage and that the internal combustion engine is operating under high load, reduces the amount of condensate collected by the collection device.
The aforementioned internal combustion engine is A supercharger comprising a turbine provided in the exhaust passage, and a compressor provided in the intake passage that operates in synchronous manner with the turbine, The intake passage is located downstream of the compressor and includes an intercooler that cools the air flowing through the intake passage . The aforementioned confluence section is located in the intake passage upstream of the compressor . The aforementioned internal combustion engine control device is The process involves determining whether the compressor rotation speed, which is the rotational speed of the compressor, is higher than the determination rotation speed. The internal combustion engine control device according to claim 1, which determines that condensed water is generated at the confluence portion, determines that the internal combustion engine is operating under high load, and further determines that the compressor rotation speed is higher than the determined rotation speed, and performs the following: reduces the cooling efficiency of the EGR gas by the EGR cooler compared to the case where the compressor rotation speed is less than or equal to the determined rotation speed.
The aforementioned internal combustion engine control device is The internal combustion engine control device according to claim 2, which, when it is determined that condensate is generated at the confluence portion, and it is determined that the internal combustion engine is operating under high load, and it is further determined that the compressor rotation speed is less than or equal to the determined rotation speed, reduces the amount of condensate collected by the collection device.
The aforementioned internal combustion engine control device is To determine whether or not condensation water is generated in the intake passage due to cooling by the intercooler, An internal combustion engine control device according to claim 2 or 3, wherein it is determined that no condensate is generated in the confluence section, and it is determined that condensate is generated in the intake passage due to cooling by the intercooler, and further, when it is determined that the internal combustion engine is not operating under high load, the device increases the cooling efficiency of the EGR gas by the EGR cooler compared to when it is determined that the internal combustion engine is operating under high load.

Description

This invention relates to an internal combustion engine control device applicable to an internal combustion engine that uses a gaseous fuel. Patent Document 1 discloses an internal combustion engine equipped with an EGR (Exhaust Gas Recirculation) device that recirculates a portion of the exhaust gas discharged from the cylinder into the intake passage. The exhaust gas recirculated into the intake passage by the EGR device is called "EGR gas." "EGR" is an abbreviation for "Exhaust Gas Recirculation." The EGR system comprises an EGR passage connected to the intake passage, an EGR cooler for cooling the EGR gas flowing through the EGR passage, a collection device for collecting condensate generated in the EGR passage, and an EGR cooler located upstream of the collection device in the EGR passage for cooling the EGR gas flowing through it . The EGR passage is connected to the portion of the intake passage upstream of the intercooler. When the control device that controls the internal combustion engine determines that condensate is generated in the intake passage due to cooling by the intercooler, it reduces the cooling efficiency of the EGR gas by the EGR cooler to suppress the generation of condensate in the intake passage. This prevents condensate from flowing into the cylinder via the intake passage. Japanese Patent Publication No. 2017-57788 Figure 1 is a configuration diagram showing the internal combustion engine control device of the first embodiment and the internal combustion engine to which the internal combustion engine control device is applied.Figure 2 is a map used to identify the operating range of the internal combustion engine shown in Figure 1.Figure 3 is a flowchart showing the processing routine executed by the internal combustion engine control device of the first embodiment.Figure 4 is a configuration diagram showing the internal combustion engine control device of the second embodiment and the internal combustion engine to which the internal combustion engine control device is applied.Figure 5 is a flowchart showing the first half of the processing routine executed by the internal combustion engine control device of the second embodiment.Figure 6 is a flowchart showing the latter half of the processing routine executed by the internal combustion engine control device of the second embodiment. (First Embodiment) The first embodiment of the internal combustion engine control device will be described below with reference to Figures 1 to 3. Figure 1 illustrates an internal combustion engine 10 mounted on a vehicle and a control device 100 applied to the internal combustion engine 10. The control device 100 corresponds to the "internal combustion engine control device". <Internal Combustion Engine> The internal combustion engine 10 comprises a plurality of cylinders 11, an intake passage 12, a plurality of fuel injection valves 13, and an exhaust passage 14. Each of the plurality of cylinders 11 houses a piston 15. Each of the plurality of pistons 15 is connected to a crankshaft 17 via a connecting rod 16. The crankshaft 17 rotates as the pistons 15 reciprocate within the plurality of cylinders 11. The crankshaft 17 corresponds to the "output shaft of the internal combustion engine 10". The intake passage 12 is connected to multiple cylinders 11. The intake passage 12 is the passage through which air flows to be introduced into the multiple cylinders 11. An intercooler 18 is provided in the intake passage 12 to cool the air flowing through it. Downstream of the intercooler 18 in the intake passage 12, a throttle valve 19 is installed to adjust the amount of air introduced into the multiple cylinders 11. Multiple fuel injectors 13 each inject gaseous fuel into the cylinder 11. Hydrogen gas is an example of gaseous fuel. In the example shown in Figure 1, port injectors are shown as fuel injectors 13, which inject gaseous fuel into the intake passage 12 downstream of the throttle valve 19. The internal combustion engine 10 may also be equipped with in-cylinder injectors 13 that directly inject gaseous fuel into the cylinder 11. In each of the cylinders 11, a mixture of air and gaseous fuel is burned by the spark discharge of the spark plug 20. This generates exhaust gas in each of the cylinders 11. The exhaust gas is discharged from the cylinders 11 into the exhaust passage 14. The exhaust gas then flows through the exhaust passage 14. The internal combustion engine 10 is equipped with an EGR system 30. The EGR system 30 is a device that recirculates a portion of the exhaust gas flowing through the exhaust passage 14 back into the intake passage 12. The exhaust gas recirculated into the intake passage 12 via the EGR system 30 is called "EGR gas." The EGR system 30 comprises an EGR passage 31, an EGR cooler 32, an EGR valve 34, and a collection device 35. The EGR passage 31 is a passage that allows the EGR gas to flow towards the intake passage 12. The first end of the EGR passage 31 is connected