Abnormality determination device for supercharging pressure sensor and abnormality determination program for supercharging pressure sensor

Abstract

To enhance frequency of determination processing related to presence / absence of an abnormality of a supercharging pressure sensor using estimation supercharging pressure.SOLUTION: An abnormality determination device for a supercharging pressure sensor can execute estimation processing (S11-S22) for estimating estimation supercharging pressure that is an estimated value of pressure of intake air in a merging passage on the basis of one of a first intake flow rate that is the amount of intake air flowing in a first passage per unit time and a second intake flow rate that is the amount of intake air flowing in a second passage per unit time. The abnormality determination device can execute determination processing (S31-S42) for determining presence / absence of an abnormality in the supercharging pressure sensor on the basis of the estimation supercharging pressure and measurement supercharging pressure that is a measurement value of the pressure of the intake air in the merging passage. The abnormality determination device estimates estimation supercharging pressure on the basis of the first intake flow rate when the first intake flow rate is the second intake flow rate or greater in the estimation processing, and estimates the estimation supercharging pressure on the basis of the second intake flow rate when the first intake flow rate is smaller than the second intake flow rate.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a device for determining an abnormality of a supercharging pressure sensor and a program for determining an abnormality of a supercharging pressure sensor. [Background technology]

[0002] The vehicle of Patent Document 1 includes an internal combustion engine, an airflow meter, a supercharging pressure sensor, and an abnormality determination device. The internal combustion engine includes an intake passage and a supercharger. The intake passage introduces intake air from outside the internal combustion engine into cylinders. The supercharger is located midway through the intake passage. The supercharger compresses the intake air flowing through the intake passage and supplies it downstream. The airflow meter is located upstream of the supercharger in the intake passage. The airflow meter detects the intake air flow rate, which is the amount of intake air flowing through the intake passage per unit time. The supercharging pressure sensor is located downstream of the supercharger in the intake passage. The supercharging pressure sensor detects a measured supercharging pressure, which is the pressure in the intake passage downstream of the supercharger.

[0003] The abnormality determination device calculates a target boost pressure as a target value for boost pressure based on the rotation speed of the crankshaft and the depression amount of the accelerator pedal. The abnormality determination device acquires a measured boost pressure detected by a boost pressure sensor. The abnormality determination device acquires an intake air flow rate detected by an air flow meter. The abnormality determination device calculates an estimated boost pressure as an estimated value of boost pressure based on the intake air flow rate. The abnormality determination device determines that there is an abnormality in the boost pressure sensor when the absolute value of the difference between the target boost pressure and the measured boost pressure is greater than a first threshold value and when the absolute value of the difference between the measured boost pressure and the estimated boost pressure is greater than a second threshold value. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5939297 Summary of the Invention [Problem to be solved by the invention]

[0005] An abnormality determination device such as that disclosed in Patent Document 1 determines whether or not there is an abnormality in the boost pressure sensor using an estimated boost pressure corresponding to the intake air flow rate detected by the air flow meter. Therefore, it is conceivable that an abnormality determination device such as that disclosed in Patent Document 1 determines whether or not there is an abnormality in the boost pressure sensor, with the necessary condition being that the detection accuracy of the air flow meter is guaranteed. However, some vehicles are equipped with multiple air flow meters, such as so-called V-type engines. In this case, if the abnormality determination device determines whether or not there is an abnormality in the boost pressure sensor, with the necessary condition being that the detection accuracy of all of the multiple air flow meters is guaranteed, for example, there is a risk that the frequency of determinations regarding the whether or not there is an abnormality in the boost pressure sensor will be excessively reduced. [Means for solving the problem]

[0006] An abnormality determination device for a supercharging pressure sensor for solving the above-mentioned problems is an abnormality determination device applied to a vehicle including an internal combustion engine, a first air flow meter, a second air flow meter, and a supercharging pressure sensor, wherein the internal combustion engine includes: a first passage that introduces intake air from outside the internal combustion engine; a second passage that introduces intake air from outside the internal combustion engine; a junction passage that connects the first passage and the second passage and allows the intake air from the first passage and the second passage to flow to a cylinder; a first supercharger that is located in the first passage and compresses the intake air flowing through the first passage and supplies it to a downstream side; and a second supercharger that is located in the second passage and compresses the intake air flowing through the second passage and supplies it to a downstream side, and the first air flow meter is located in the first passage and is capable of detecting a first intake air flow rate that is the amount of intake air flowing through the first passage per unit time. the second air flow meter is located in the second passage and is capable of detecting a second intake air flow rate which is the amount of intake air flowing through the second passage per unit time; the boost pressure sensor is located in the merging passage and is capable of detecting a measured boost pressure which is a measurement value of the pressure of the intake air in the merging passage; and the system is capable of executing an estimation process of estimating an estimated boost pressure which is an estimated value of the pressure of the intake air in the merging passage based on one of the first intake air flow rate and the second intake air flow rate; and a determination process of determining whether or not there is an abnormality in the boost pressure sensor based on the estimated boost pressure and the measured boost pressure, wherein the estimation process estimates the estimated boost pressure based on the first intake air flow rate when the first intake air flow rate is equal to or greater than the second intake air flow rate, and estimates the estimated boost pressure based on the second intake air flow rate when the first intake air flow rate is less than the second intake air flow rate.

[0007] An abnormality determination program for a supercharging pressure sensor for solving the above-mentioned problems is applied to an abnormality determination device for a vehicle including an internal combustion engine, a first air flow meter, a second air flow meter, and a supercharging pressure sensor, wherein the internal combustion engine includes: a first passage that introduces intake air from outside the internal combustion engine; a second passage that introduces intake air from outside the internal combustion engine; a junction passage that connects the first passage and the second passage and causes the intake air from the first passage and the second passage to flow to a cylinder; a first supercharger that is located in the first passage and compresses the intake air flowing through the first passage and supplies it to a downstream side; and a second supercharger that is located in the second passage and compresses the intake air flowing through the second passage and supplies it to a downstream side, and the first air flow meter is located in the first passage and is capable of detecting a first intake air flow rate that is the amount of intake air flowing through the first passage per unit time, The second air flow meter is located in the second passage and is capable of detecting a second intake air flow rate, which is the amount of intake air flowing through the second passage per unit time. The boost pressure sensor is located in the merging passage and is capable of detecting a measured boost pressure, which is a measurement value of the pressure of the intake air in the merging passage. The abnormality determination device is capable of executing an estimation process of estimating an estimated boost pressure, which is an estimated value of the pressure of the intake air in the merging passage, based on one of the first intake air flow rate and the second intake air flow rate, and a determination process of determining whether or not there is an abnormality in the boost pressure sensor, based on the estimated boost pressure and the measured boost pressure. In the estimation process, when the first intake air flow rate is equal to or greater than the second intake air flow rate, the estimated boost pressure is estimated based on the first intake air flow rate, and when the first intake air flow rate is less than the second intake air flow rate, the estimated boost pressure is estimated based on the second intake air flow rate. [Effects of the Invention]

[0008] According to the above configuration, it is possible to increase the frequency of the process of determining whether or not there is an abnormality in the boost pressure sensor using the estimated boost pressure. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a vehicle. [Figure 2] FIG. 2 is a flowchart showing the determination control. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Vehicle Overview> An embodiment of the present invention will be described below with reference to Figures 1 and 2. First, a general configuration of a vehicle 100 will be described. In the following description, when simply referring to upstream and downstream, this refers to upstream and downstream in the flow of intake air, exhaust air, etc.

[0011] As shown in Fig. 1, a vehicle 100 includes an internal combustion engine 10. In this embodiment, the internal combustion engine 10 is a so-called V-engine. The internal combustion engine 10 includes a first passage 11, a second passage 12, and a junction passage 13. The internal combustion engine 10 also includes a first engine body 21, a second engine body 22, a first exhaust passage 31, and a second exhaust passage 32.

[0012] The first engine body 21 has three cylinders 21A. Each cylinder 21A is a space for burning a mixture of fuel and intake air. The second engine body 22 has three cylinders 22A. Each cylinder 22A is a space for burning a mixture of fuel and intake air. The cylinders 21A of the first engine body 21 and the cylinders 22A of the second engine body 22 introduce intake air via a first passage 11, a second passage 12, and a junction passage 13.

[0013] The first passage 11 is a passage for introducing intake air from outside the internal combustion engine 10. The second passage 12 is a passage for introducing intake air from outside the internal combustion engine 10. The upstream end of the junction passage 13 is connected to the downstream end of the first passage 11 and the downstream end of the second passage 12. That is, the junction passage 13 connects the first passage 11 and the second passage 12. The junction passage 13 distributes intake air from the first passage 11 and the second passage 12. A portion of the junction passage 13, including the downstream end, is roughly branched into two. The downstream end of one of the two branched passages is connected to each cylinder 21A of the first engine body 21. The downstream end of the other of the two branched passages is connected to each cylinder 22A of the second engine body 22.

[0014] The upstream end of the first exhaust passage 31 is connected to each cylinder 21A of the first engine body 21. The first exhaust passage 31 discharges exhaust from each cylinder 21A to the outside of the internal combustion engine 10. The upstream end of the second exhaust passage 32 is connected to each cylinder 22A of the second engine body 22. The second exhaust passage 32 discharges exhaust from each cylinder 22A to the outside of the internal combustion engine 10.

[0015] The internal combustion engine 10 includes a first turbocharger 40 and a second turbocharger 50. The first turbocharger 40 includes a first compressor wheel 41, a first connecting shaft 42, a first turbine wheel 43, a first bypass passage 44, and a first wastegate valve 45.

[0016] The first compressor wheel 41 is located midway through the first passage 11. The first compressor wheel 41 is connected to the first turbine wheel 43 via a first connecting shaft 42. The first turbine wheel 43 is located midway through the first exhaust passage 31. In the first turbocharger 40, when the first turbine wheel 43 is rotated by the exhaust gas flowing through the first exhaust passage 31, the first connecting shaft 42 and the first compressor wheel 41 are rotated. As a result, the first compressor wheel 41 compresses the intake air flowing through the first passage 11 and supplies the compressed air downstream of the first compressor wheel 41.

[0017] A first end of the first bypass passage 44 is connected to a portion of the first exhaust passage 31 that is upstream of the first turbine wheel 43. A second end of the first bypass passage 44 is connected to a portion of the first exhaust passage 31 that is downstream of the first turbine wheel 43. The first bypass passage 44 allows the exhaust gas to bypass the first turbine wheel 43. The first wastegate valve 45 is located near the downstream end of the first bypass passage 44. The first wastegate valve 45 adjusts the amount of exhaust gas flowing through the first bypass passage 44. In the present embodiment, the first turbocharger 40 is an example of a first supercharger.

[0018] The second turbocharger 50 includes a second compressor wheel 51 , a second connecting shaft 52 , a second turbine wheel 53 , a second bypass passage 54 , and a second wastegate valve 55 .

[0019] The second compressor wheel 51 is located in the middle of the second passage 12. The second compressor wheel 51 is connected to the second turbine wheel 53 via a second connecting shaft 52. The second turbine wheel 53 is located in the middle of the second exhaust passage 32. In the second turbocharger 50, when the second turbine wheel 53 is rotated by the exhaust gas flowing through the second exhaust passage 32, the second connecting shaft 52 and the second compressor wheel 51 are rotated. As a result, the second compressor wheel 51 compresses the intake air flowing through the second passage 12 and supplies the compressed air downstream of the second compressor wheel 51.

[0020] A first end of the second bypass passage 54 is connected to a portion of the second exhaust passage 32 that is upstream of the second turbine wheel 53. A second end of the second bypass passage 54 is connected to a portion of the second exhaust passage 32 that is downstream of the second turbine wheel 53. The second bypass passage 54 allows the exhaust gas to bypass the second turbine wheel 53. The second wastegate valve 55 is located near the downstream end of the second bypass passage 54. The second wastegate valve 55 adjusts the amount of exhaust gas flowing through the second bypass passage 54. In the present embodiment, the second turbocharger 50 is an example of a second supercharger.

[0021] The internal combustion engine 10 includes an intercooler 61, a throttle valve 62, a plurality of fuel injection valves 63, a first catalyst 71, and a second catalyst 72. The intercooler 61 is located midway through the merging passage 13. The intercooler 61 cools the intake air flowing through the merging passage 13. The throttle valve 62 is located in a portion of the merging passage 13 downstream of the intercooler 61. The throttle valve 62 adjusts the amount of intake air flowing through the merging passage 13.

[0022] The internal combustion engine 10 is equipped with six fuel injection valves 63. Three of the six fuel injection valves 63 are located near the first engine body 21 in the junction passage 13. Each of the three fuel injection valves 63 injects fuel supplied from a fuel tank (not shown) into the junction passage 13 to supply fuel to each cylinder 21A of the first engine body 21. The remaining three of the six fuel injection valves 63 are located near the second engine body 22 in the junction passage 13. Each of the three fuel injection valves 63 injects fuel supplied from a fuel tank (not shown) into the junction passage 13 to supply fuel to each cylinder 22A of the second engine body 22.

[0023] The first catalyst 71 is located in a portion of the first exhaust passage 31 downstream of the first turbine wheel 43. The first catalyst 71 purifies the exhaust gas flowing through the first exhaust passage 31. The second catalyst 72 is located in a portion of the second exhaust passage 32 downstream of the second turbine wheel 53. The second catalyst 72 purifies the exhaust gas flowing through the second exhaust passage 32.

[0024] As shown in FIG. 1, the vehicle 100 includes a first air flow meter 81, a second air flow meter 82, a supercharging pressure sensor 83, an accelerator operation amount sensor 84, a vehicle speed sensor 85, and a display 89.

[0025] The first air flow meter 81 is located in a portion of the first passage 11 upstream of the first compressor wheel 41. The first air flow meter 81 detects a first intake air flow rate GA1, which is the amount of intake air flowing through the first passage 11 per unit time.

[0026] The second air flow meter 82 is located in a portion of the second passage 12 upstream of the second compressor wheel 51. The second air flow meter 82 detects a second intake air flow rate GA2, which is the amount of intake air flowing through the second passage 12 per unit time.

[0027] The boost pressure sensor 83 is located in a portion of the junction passage 13 upstream of the intercooler 61. The boost pressure sensor 83 detects a measured boost pressure PM, which is a measurement value of the pressure of the intake air in the junction passage 13. Specifically, the measured boost pressure PM is a measurement value of the pressure of the intake air in the portion of the junction passage 13 upstream of the intercooler 61.

[0028] The accelerator operation amount sensor 84 detects an accelerator operation amount ACC, which is the amount of operation of the accelerator pedal operated by the driver of the vehicle 100. The vehicle speed sensor 85 detects a vehicle speed SP, which is the speed of the vehicle 100. The display 89 is located near the driver's seat of the vehicle 100. The display 89 is capable of displaying various types of information.

[0029] 1, the vehicle 100 is equipped with a control device 90. The control device 90 acquires various information from a first air flow meter 81, a second air flow meter 82, a boost pressure sensor 83, an accelerator operation amount sensor 84, and a vehicle speed sensor 85.

[0030] The control device 90 includes an execution device 91 and a storage device 92. An example of the execution device 91 is a CPU. The storage device 92 includes a read-only ROM, a readable / writable volatile RAM, and a readable / writable non-volatile storage. The storage device 92 stores various programs and various data in advance. Specifically, the storage device 92 stores a control program 92A in advance as one of the various programs. The storage device 92 also stores a first relationship defining model M1 and a second relationship defining model M2 in advance as various data. The first relationship defining model M1 and the second relationship defining model M2 will be described in detail later. The execution device 91 executes the control program 92A stored in the storage device 92 to perform various processes described later. In this embodiment, the control device 90 is an example of an abnormality determination device. The control program 92A is an example of an abnormality determination program.

[0031] An execution device 91 of the control device 90 calculates a vehicle required driving force, which is a required value of driving force necessary for the vehicle 100 to travel, based on the accelerator operation amount ACC and the vehicle speed SP. The execution device 91 controls the internal combustion engine 10 based on the vehicle required driving force. Specifically, the execution device 91 outputs a control signal to the internal combustion engine 10 to control the opening degree of the throttle valve 62, the fuel injection amount from the fuel injection valve 63, the opening degree of the first wastegate valve 45, the opening degree of the second wastegate valve 55, etc. The execution device 91 can also control a display 89 by outputting a control signal to the display 89.

[0032] <Decision control> Next, the determination control executed by the control device 90 will be described with reference to Fig. 2. This determination control is a control for determining whether or not there is an abnormality in the supercharging pressure sensor 83. In this embodiment, the execution device 91 of the control device 90 starts the determination control at each predetermined control cycle, with the necessary condition being that the internal combustion engine 10 is operating.

[0033] 2, when the execution unit 91 of the control device 90 starts the determination control, it executes the process of step S11. In step S11, the execution unit 91 determines whether the first intake flow rate GA1 is equal to or greater than the second intake flow rate GA2. In step S11, if the execution unit 91 determines that the first intake flow rate GA1 is equal to or greater than the second intake flow rate GA2 (S11: YES), the execution unit 91 proceeds to step S21.

[0034] In step S21, the execution unit 91 estimates the estimated boost pressure PE, which is an estimated value of the pressure of the intake air in the junction passage 13, based on the first intake air flow rate GA1. Specifically, the execution unit 91 estimates the estimated boost pressure PE using a first relationship specifying model M1. Here, the first relationship specifying model M1 is a model that specifies the relationship between the first intake air flow rate GA1 and the estimated boost pressure PE. In other words, the first relationship specifying model M1 is a model that outputs the estimated boost pressure PE when the first intake air flow rate GA1 is input. For example, the first relationship specifying model M1 outputs a higher value as the estimated boost pressure PE as the input first intake air flow rate GA1 increases. Note that, in the first relationship specifying model M1, the relationship between the first intake air flow rate GA1 and the estimated boost pressure PE is specified in advance through experiments, simulations, etc. In step S21, the executing unit 91 inputs the first intake air flow rate GA1 into the first relationship defining model M1 to estimate an estimated boost pressure PE corresponding to the first intake air flow rate GA1. In this embodiment, the estimated boost pressure PE is an estimated value of the pressure of the intake air in the portion of the junction passage 13 upstream of the intercooler 61. After step S21, the executing unit 91 proceeds to step S30.

[0035] On the other hand, in the above-described step S11, if the execution unit 91 determines that the first intake flow rate GA1 is less than the second intake flow rate GA2 (S11: NO), the execution unit 91 advances the processing to step S22.

[0036] In step S22, the execution unit 91 estimates the estimated boost pressure PE based on the second intake air flow rate GA2. Specifically, the execution unit 91 estimates the estimated boost pressure PE using a second relationship specification model M2. Here, the second relationship specification model M2 is a model that specifies the relationship between the second intake air flow rate GA2 and the estimated boost pressure PE. In other words, the second relationship specification model M2 is a model that outputs the estimated boost pressure PE by inputting the second intake air flow rate GA2. For example, the second relationship specification model M2 outputs a higher value as the estimated boost pressure PE as the input second intake air flow rate GA2 increases. Note that the relationship between the second intake air flow rate GA2 and the estimated boost pressure PE in the second relationship specification model M2 is specified in advance through experiments, simulations, etc. In step S22, the execution unit 91 inputs the second intake air flow rate GA2 into the second relationship specification model M2 to estimate the estimated boost pressure PE according to the second intake air flow rate GA2. In this embodiment, the processes of steps S11 to S22 are an example of an estimation process for estimating the estimated supercharging pressure PE based on one of the first intake air flow rate GA1 and the second intake air flow rate GA2. After step S22, the execution unit 91 advances the process to step S30.

[0037] In step S30, the executing unit 91 determines whether the deviation between the first intake flow rate GA1 and the second intake flow rate GA2 is large. Specifically, the executing unit 91 determines that the deviation between the first intake flow rate GA1 and the second intake flow rate GA2 is large when the absolute value of the difference between the first intake flow rate GA1 and the second intake flow rate GA2 is equal to or greater than a predetermined reference value Z. On the other hand, the executing unit 91 determines that the deviation between the first intake flow rate GA1 and the second intake flow rate GA2 is small when the absolute value of the difference between the first intake flow rate GA1 and the second intake flow rate GA2 is less than the predetermined reference value Z. The reference value Z is predetermined through experiments, simulations, etc. as a threshold value for determining the magnitude of the absolute value of the difference between the first intake flow rate GA1 and the second intake flow rate GA2. In step S30, when the execution unit 91 determines that the deviation between the first intake air flow rate GA1 and the second intake air flow rate GA2 is small (S30: NO), the execution unit 91 ends the current determination control.

[0038] On the other hand, if the executing unit 91 determines in step S30 that the deviation between the first intake flow rate GA1 and the second intake flow rate GA2 is large (S30: YES), the executing unit 91 proceeds to step S31. In other words, the executing unit 91 proceeds to step S31 on the condition that the absolute value of the difference between the first intake flow rate GA1 and the second intake flow rate GA2 is equal to or greater than a predetermined reference value Z.

[0039] In step S31, the executing unit 91 determines whether the estimated boost pressure PE is higher than the measured boost pressure PM. If the executing unit 91 determines in step S31 that the estimated boost pressure PE is higher than the measured boost pressure PM (S31: YES), the executing unit 91 proceeds to step S41. In step S41, the executing unit 91 determines that the boost pressure sensor 83 is normal. After step S41, the executing unit 91 ends the current determination control.

[0040] On the other hand, if the execution unit 91 determines in step S31 that the estimated boost pressure PE is equal to or lower than the measured boost pressure PM (S31: NO), the execution unit 91 advances the process to step S42.

[0041] In step S42, the execution device 91 determines that the supercharging pressure sensor 83 is abnormal. Then, the execution device 91 outputs a control signal to the display 89, thereby notifying the driver of the vehicle 100, etc., on the display 89 that the supercharging pressure sensor 83 is abnormal. In this embodiment, the processing of steps S31 to S42 is an example of a determination process for determining whether or not the supercharging pressure sensor 83 is abnormal, based on the estimated supercharging pressure PE and the measured supercharging pressure PM. After step S42, the execution device 91 ends the current determination control.

[0042] <Operation of this embodiment> In the internal combustion engine 10, the amount of intake air flowing through the first passage 11 per unit time may temporarily decrease due to some factor, or the amount of intake air flowing through the second passage 12 per unit time may temporarily decrease. For example, when the amount of intake air flowing through the second passage 12 per unit time is small, the amount of intake air actually flowing through the second passage 12 per unit time may deviate from the second intake air flow rate GA2 detected by the second air flow meter 82. That is, when the amount of intake air flowing through the second passage 12 per unit time is small, the detection accuracy of the second air flow meter 82 decreases. As a result, the estimation accuracy of the estimated boost pressure PE based on the second intake air flow rate GA2 detected by the second air flow meter 82 decreases. As a result, in a configuration that executes a determination process to determine whether or not there is an abnormality in the boost pressure sensor 83 based on the estimated boost pressure PE and the measured boost pressure PM, the determination accuracy of the determination process decreases.

[0043] Therefore, in an internal combustion engine 10 equipped with a first air flow meter 81 and a second air flow meter 82, it is conceivable to estimate the estimated boost pressure PE using the detected values ​​of the two sensors, with the necessary condition being that the detection accuracy of both sensors is guaranteed. As a specific example, it is conceivable to estimate the estimated boost pressure PE, with the necessary condition being that the first intake air flow rate GA1 and the second intake air flow rate GA2 are equal to or greater than a predetermined specified value. However, with the above-described determination configuration, there is a risk that the frequency of determining whether or not there is an abnormality in the boost pressure sensor 83 will decrease due to a decrease in the frequency of estimating the estimated boost pressure PE.

[0044] 2, the execution unit 91 of the control device 90 estimates the estimated boost pressure PE based on one of the first intake air flow rate GA1 and the second intake air flow rate GA2. Specifically, when the first intake air flow rate GA1 is equal to or greater than the second intake air flow rate GA2, the execution unit 91 estimates the estimated boost pressure PE based on the first intake air flow rate GA1. When the first intake air flow rate GA1 is less than the second intake air flow rate GA2, the execution unit 91 estimates the estimated boost pressure PE based on the second intake air flow rate GA2. Then, the execution unit 91 executes a determination process to determine whether or not there is an abnormality in the boost pressure sensor 83 based on the estimated boost pressure PE estimated as described above and the measured boost pressure PM.

[0045] <Effects of this embodiment> (1) According to this embodiment, the estimated boost pressure PE is estimated more frequently than in a configuration in which the estimated boost pressure PE is estimated on the condition that the detection accuracy of both the first air flow meter 81 and the second air flow meter 82 is guaranteed. As a result, it is possible to prevent a decrease in the frequency of determining whether or not there is an abnormality in the boost pressure sensor 83 due to a decrease in the frequency of estimating the estimated boost pressure PE.

[0046] Furthermore, according to this embodiment, the estimated boost pressure PE is estimated based on the higher value of the first intake air flow rate GA1 and the second intake air flow rate GA2. This improves the estimation accuracy of the estimated boost pressure PE compared to, for example, a case where the estimated boost pressure PE is estimated based on the lower value of the first intake air flow rate GA1 and the second intake air flow rate GA2, i.e., the detection value of the first air flow meter 81 or the second air flow meter 82, whichever has lower detection accuracy.

[0047] (2) In the vehicle 100, for example, when the first intake air flow rate GA1 is greater than the second intake air flow rate GA2, the estimated boost pressure PE based on the first intake air flow rate GA1 is higher than when the first intake air flow rate GA1 is the same as the second intake air flow rate GA2. As a result, if the boost pressure sensor 83 is normal, the estimated boost pressure PE estimated based on the first intake air flow rate GA1 tends to be higher than the measured boost pressure PM.

[0048] In this regard, in the determination process, when the estimated boost pressure PE is equal to or less than the measured boost pressure PM, the execution device 91 determines that the boost pressure sensor 83 is abnormal. As a result, when the estimated boost pressure PE is equal to or less than the measured boost pressure PM, in other words, when it is assumed that the boost pressure sensor 83 is abnormal, it can be determined that the boost pressure sensor 83 is abnormal.

[0049] (3) In the vehicle 100, for example, the absolute value of the difference between the first intake air flow rate GA1 and the second intake air flow rate GA2 is equal to or greater than a predetermined reference value Z, and the first intake air flow rate GA1 is greater than the second intake air flow rate GA2. In this situation, if the boost pressure sensor 83 is normal, the estimated boost pressure PE estimated based on the first intake air flow rate GA1 should be correspondingly higher than the measured boost pressure PM, compared to when the absolute value of the difference between the first intake air flow rate GA1 and the second intake air flow rate GA2 is less than the reference value Z. Therefore, if the estimated boost pressure PE is equal to or less than the measured boost pressure PM, there is a particularly high possibility that the boost pressure sensor 83 is abnormal.

[0050] In this regard, in step S30, the executing unit 91 proceeds to step S31 with the necessary condition that the absolute value of the difference between the first intake air flow rate GA1 and the second intake air flow rate GA2 is equal to or greater than a predetermined reference value Z. Then, the executing unit 91 determines that the boost pressure sensor 83 is abnormal if the estimated boost pressure PE is equal to or less than the measured boost pressure PM. This makes it possible to determine that the boost pressure sensor 83 is abnormal when there is a particularly high possibility that the boost pressure sensor 83 is abnormal. As a result, the determination accuracy of the determination process can be improved.

[0051] (4) In general, even if the amount of intake air flowing through the first passage 11 per unit time and the amount of intake air flowing through the second passage 12 per unit time are designed to be the same, the average value of one of the two values ​​may be greater than the average value of the other. Therefore, if a common relationship specification model is used to estimate the estimated boost pressure PE based on either the first intake air flow rate GA1 or the second intake air flow rate GA2, the estimation accuracy of the estimated boost pressure PE may decrease due to the steady-state bias described above.

[0052] In this regard, when the first intake air flow rate GA1 is equal to or greater than the second intake air flow rate GA2, the executing unit 91 inputs the first intake air flow rate GA1 into the first relationship specifying model M1 to estimate the estimated boost pressure PE corresponding to the first intake air flow rate GA1. Furthermore, when the first intake air flow rate GA1 is less than the second intake air flow rate GA2, the executing unit 91 inputs the second intake air flow rate GA2 into the second relationship specifying model M2 to estimate the estimated boost pressure PE corresponding to the second intake air flow rate GA2. According to this embodiment, by selectively using the first relationship specifying model M1 and the second relationship specifying model M2 as described above, it is possible to prevent a decrease in the estimation accuracy of the estimated boost pressure PE.

[0053] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0054] In the above embodiment, the determination control may be changed. For example, the method of estimating the estimated supercharging pressure PE in steps S21 and S22 may be changed. As a specific example, in step S21, the executing unit 91 may estimate the estimated supercharging pressure PE corresponding to the first intake air flow rate GA1 by inputting the first intake air flow rate GA1 into a relationship defining model common to steps S21 and S22, instead of the first relationship defining model M1. Similarly, in step S22, the executing unit 91 may estimate the estimated supercharging pressure PE corresponding to the second intake air flow rate GA2 by inputting the second intake air flow rate GA2 into a relationship defining model common to steps S21 and S22, instead of the second relationship defining model M2.

[0055] For example, regardless of the determination result of step S30, a determination process may be executed to determine whether or not there is an abnormality in the boost pressure sensor 83 based on the estimated boost pressure PE and the measured boost pressure PM. As a specific example, when a negative determination is made in step S30, the execution device 91 may execute a determination process to determine whether or not there is an abnormality in the boost pressure sensor 83 based on the estimated boost pressure PE and the measured boost pressure PM. Also, as a specific example, the process of step S30 may be omitted. In this case, after step S21, the execution device 91 may simply proceed with the process to step S31. Similarly, after step S22, the execution device 91 may simply proceed with the process to step S31.

[0056] For example, the processing of step S31 may be changed. As a specific example, in step S31, the executing unit 91 may determine whether the estimated boost pressure PE is equal to or greater than the measured boost pressure PM. In other words, in the determination processing, the executing unit 91 may determine that the boost pressure sensor 83 is abnormal if the estimated boost pressure PE is less than the measured boost pressure PM.

[0057] In the above embodiment, the configuration of the vehicle 100 may be changed. For example, the first supercharger is not limited to the first turbocharger 40. As a specific example, the first supercharger may be a first supercharger. Furthermore, for example, the second supercharger is not limited to the second turbocharger 50. As a specific example, the second supercharger may be a second supercharger.

[0058] For example, the position of the boost pressure sensor 83 may be changed. As a specific example, the boost pressure sensor 83 may be located in a portion of the junction passage 13 downstream of the intercooler 61.

[0059] For example, the configuration of the control device 90 may be changed. Specifically, the control device 90 may be configured as a circuit including one or more processors that execute various processes according to a computer program (software). The control device 90 may also be configured as a circuit including one or more dedicated hardware circuits, such as an application-specific integrated circuit (ASIC), that execute at least some of the various processes, or a combination thereof. The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute processes. The memory, i.e., computer-readable medium, includes any medium accessible by a general-purpose or dedicated computer. [Explanation of symbols]

[0060] 10...internal combustion engine 11...first passage 12...second passage 13...merging passage 21...first engine body 21A...cylinder 22...second engine body 22A...cylinder 31...first exhaust passage 32...second exhaust passage 40...first turbocharger 41...first compressor wheel 42...first connecting shaft 43...first turbine wheel 44...first bypass passage 45...first wastegate valve 50...second turbocharger 51...second compressor wheel 52...second connecting shaft 53...second turbine wheel 54...second bypass passage 55...second wastegate valve 61...intercooler 62...throttle valve 63...fuel injector 71...first catalyst 72...second catalyst 81...first air flow meter 82...second air flow meter 83...boost pressure sensor 84...Accelerator operation amount sensor 85...Vehicle speed sensor 89...Display 90...Control device 91...Execution device 92...Storage device 92A...Control program M1...First relationship specification model M2...Second relationship specification model 100...Vehicle

Claims

1. An abnormality determination device applied to a vehicle including an internal combustion engine, a first air flow meter, a second air flow meter, and a supercharging pressure sensor, The internal combustion engine includes: a first passage for introducing intake air from outside the internal combustion engine; a second passage for introducing intake air from outside the internal combustion engine; a confluence passage connecting the first passage and the second passage and allowing intake air from the first passage and the second passage to flow into a cylinder; a first supercharger located in the first passage and configured to compress intake air flowing through the first passage and supply the compressed air to a downstream side; a second supercharger located in the second passage and configured to compress intake air flowing through the second passage and supply the compressed air to a downstream side; Equipped with the first air flow meter is located in the first passage and is capable of detecting a first intake air flow rate, which is an amount of intake air flowing through the first passage per unit time; the second air flow meter is located in the second passage and is capable of detecting a second intake air flow rate, which is an amount of intake air flowing through the second passage per unit time; the boost pressure sensor is located in the junction passage and is capable of detecting a measured boost pressure which is a measurement value of the pressure of intake air in the junction passage, an estimation process for estimating an estimated supercharging pressure, which is an estimated value of the pressure of the intake air in the junction passage, based on one of the first intake air flow rate and the second intake air flow rate; a determination process for determining whether or not the boost pressure sensor has an abnormality based on the estimated boost pressure and the measured boost pressure; is executable, In the estimation process, When the first intake air flow rate is equal to or greater than the second intake air flow rate, the estimated supercharging pressure is estimated based on the first intake air flow rate, and when the first intake air flow rate is less than the second intake air flow rate, the estimated supercharging pressure is estimated based on the second intake air flow rate. A device for determining abnormalities in a boost pressure sensor.

2. In the determination process, When the estimated boost pressure is equal to or less than the measured boost pressure, it is determined that the boost pressure sensor is abnormal.

2. The device for determining abnormality of a boost pressure sensor according to claim 1.

3. The determination process is performed under the condition that the absolute value of the difference between the first intake flow rate and the second intake flow rate is equal to or greater than a predetermined reference value.

3. The device for determining abnormality of a boost pressure sensor according to claim 2.

4. a first relationship definition model that defines a relationship between the first intake flow rate and the estimated supercharging pressure is stored; a second relationship definition model that defines a relationship between the second intake flow rate and the estimated supercharging pressure is stored; In the estimation process, when the first intake air flow rate is equal to or greater than the second intake air flow rate, estimating the estimated supercharging pressure according to the first intake air flow rate by inputting the first intake air flow rate into the first relationship defining model; When the first intake flow rate is less than the second intake flow rate, the second intake flow rate is input to the second relationship specification model to estimate the estimated supercharging pressure according to the second intake flow rate. The abnormality determination device for a boost pressure sensor according to any one of claims 1 to 3.

5. The present invention is applied to an abnormality determination device for a vehicle including an internal combustion engine, a first air flow meter, a second air flow meter, and a supercharging pressure sensor, The internal combustion engine includes: a first passage for introducing intake air from outside the internal combustion engine; a second passage for introducing intake air from outside the internal combustion engine; a confluence passage connecting the first passage and the second passage and allowing intake air from the first passage and the second passage to flow into a cylinder; a first supercharger located in the first passage and configured to compress intake air flowing through the first passage and supply the compressed air to a downstream side; a second supercharger located in the second passage and configured to compress intake air flowing through the second passage and supply the compressed air to a downstream side; Equipped with the first air flow meter is located in the first passage and is capable of detecting a first intake air flow rate, which is an amount of intake air flowing through the first passage per unit time; the second air flow meter is located in the second passage and is capable of detecting a second intake air flow rate, which is an amount of intake air flowing through the second passage per unit time; the boost pressure sensor is located in the junction passage and is capable of detecting a measured boost pressure which is a measurement value of the pressure of intake air in the junction passage, The abnormality determination device an estimation process for estimating an estimated supercharging pressure, which is an estimated value of the pressure of the intake air in the junction passage, based on one of the first intake air flow rate and the second intake air flow rate; a determination process for determining whether or not the boost pressure sensor has an abnormality based on the estimated boost pressure and the measured boost pressure; Make it executable, In the estimation process, When the first intake flow rate is equal to or greater than the second intake flow rate, the estimated supercharging pressure is estimated based on the first intake flow rate, and when the first intake flow rate is less than the second intake flow rate, the estimated supercharging pressure is estimated based on the second intake flow rate. A program to determine abnormalities in the boost pressure sensor.

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