JP2016089708A - engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine capable of calculating an appropriate rotational speed Tn of a supercharger irrespective of an operational environment or operational condition and performing appropriate control under a combination with other results of measurement.SOLUTION: This invention relates to an engine 1 with a supercharger 4 including a supercharger rotational speed map M1 indicating a relation among an average suction flow rate If, an average supercharging pressure Ip and an average supercharger rotational speed Tn. A correction average supercharger rotational speed RTn in which an estimated average supercharger rotational speed ETn calculated in reference to the supercharger rotational speed map M1 on the basis of an average suction flow rate If detected by a suction flow rate detection sensor 14 and an average supercharger pressure Ip detected by the supercharger pressure sensor 15 is corrected by a surrounding air temperature Bt and an atmospheric pressure Bp is calculated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an engine. In particular, it relates to a turbocharged engine.

  2. Description of the Related Art Conventionally, an engine with a supercharger provided with a supercharger rotation speed detection device (supercharger rotation speed sensor) that detects the rotation speed of a compressor or turbine of the supercharger is known. The turbocharged engine has an appropriate turbocharger rotation speed map that shows the relationship between the fuel injection amount, the engine rotation speed, and the turbocharger rotation speed. There is one that corrects the fuel injection amount by comparison with the speed map. For example, as in Patent Document 1.

  The engine described in Patent Literature 1 corrects the fuel injection amount on the basis of an appropriate supercharger rotation speed map created based on a measurement result of an engine operated under a predetermined condition. However, the turbocharger may have different turbocharger rotation speeds depending on the atmospheric pressure or the atmospheric temperature even with the same fuel injection amount and engine rotation speed. Therefore, if the atmospheric pressure or temperature during operation of the engine is different from the conditions for creating the appropriate turbocharger rotation speed map, the engine will set the turbocharger rotation speed to a value based on the appropriate turbocharger rotation speed map. Even if the fuel injection amount is corrected, there is a possibility that the operation state is not appropriate.

JP 2009-221881 A

  The present invention has been made in view of such problems, and can calculate an appropriate turbocharger rotation speed regardless of the operating environment and operating conditions, and can perform appropriate control in combination with other measurement results. The purpose is to provide.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in the present invention, the engine is a supercharger equipped with a supercharger rotation speed map showing the relationship between the average intake flow rate, the average supercharging pressure, and the average supercharger rotation speed, and the intake flow rate detection sensor A corrected average in which the estimated average turbocharger speed calculated from the turbocharger speed map based on the detected average intake air flow rate and the average boost pressure detected by the boost pressure sensor is corrected by the outside air temperature and atmospheric pressure The turbocharger rotational speed is calculated.

  That is, in the present invention, a turbocharger rotation speed detection device that calculates a turbocharger rotation speed by detecting a compressor or a turbine blade of the turbocharger, and the turbocharger calculated by the rotation speed detection device is provided. The estimated average intake air flow rate is calculated from the supercharger rotation speed map based on the average supercharger rotation speed and the average value of the supercharging pressure.

  That is, in the present invention, the distribution ratio of the intake air of each cylinder is calculated from the number of detections of the compressor or turbine blade of the supercharger detected by the supercharger rotation speed detection device during the intake stroke of each cylinder. Is.

  That is, in the present invention, when the difference or ratio between the average supercharger rotational speed and the corrected supercharger rotational speed exceeds a threshold, an abnormality has occurred in the supercharger rotational speed detection device. The corrected supercharger rotational speed is set as the supercharger rotational speed.

  That is, in the present invention, when fuel is injected based on an arbitrary target injection amount, the fuel injection amount is corrected from the change amount of the intake flow rate detected by the intake flow rate sensor or the change amount of the estimated intake flow rate. Is.

  As effects of the present invention, the following effects can be obtained.

  According to the present invention, the average supercharger rotation speed in consideration of the operating environment and conditions is calculated by correcting data measured under predetermined conditions. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

  According to the present invention, the average intake flow rate is calculated from the data measured under predetermined conditions and the actual measurement values in consideration of the operating environment and conditions. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

  According to the present invention, the average supercharger rotation speed is not calculated from an abnormal measurement result. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

  According to the present invention, the engine is controlled based on the change in the intake air flow rate of the supercharger that has a small inertia and easily changes in the operating condition. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

The block diagram which shows the outline of the engine with a supercharger which concerns on one Embodiment of this invention. The figure showing the graph which shows the relationship between the intake air flow rate of the supercharger which concerns on one Embodiment of this invention, a supercharging pressure, and a rotational speed. BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows the structure of the supercharger which concerns on one Embodiment of this invention, and a supercharger rotational speed detection apparatus. The partial cross section figure which shows the positional relationship of the detection part and braid | blade of the supercharger rotational speed detection apparatus which concerns on one Embodiment of this invention. (A) A schematic diagram and a waveform diagram showing a state at the moment when the blade of the supercharger rotation speed detection device according to the embodiment of the present invention enters the detection region of the detection device. (B) Similarly, the blade is the detection device. The figure which shows the schematic and waveform diagram showing the state of the moment which left the detection area | region. The figure showing the graph which shows the blade detection waveform figure of the supercharger rotational speed detection apparatus which concerns on one Embodiment of this invention, and time. The figure which shows the flowchart showing the control which determines the state of the compressor or turbine in the supercharger rotational speed detection apparatus which concerns on one Embodiment of this invention. The figure showing the graph which shows the braid | blade detection waveform figure of the supercharger rotational speed detection apparatus in each process of the engine which concerns on one Embodiment of this invention. The figure which shows the graph showing the valve opening time of a fuel injection valve, and the relationship of injection amount.

  Below, the engine 1 provided with the supercharger 4 which concerns on one Embodiment of this invention is demonstrated using FIG.

  As shown in FIG. 1, the engine 1 is a diesel engine 1, and in this embodiment, is an in-line four-cylinder engine 1 having four cylinders. In the present embodiment, the in-line four-cylinder engine 1 having one supercharger 4 is used, but the present invention is not limited to this, and the engine 1 having a supercharger (for example, a two-stage supercharger). If it is.

  The engine 1 rotates the output shaft by mixing external air and fuel supplied from the fuel injection valve 2 in each cylinder 1a, 1b, 1c, and 1d and burning them. The engine 1 includes an intake device 3 that takes in outside air and an exhaust device 8 that discharges exhaust to the outside. The engine 1 includes an engine rotation speed detection sensor 11, an injection amount detection sensor 12 for the fuel injection valve 2, a crank angle detection sensor 13, an intake air flow detection sensor 14, a supercharging pressure detection sensor 15, and a supercharger rotation speed detection device. 16, the outside air temperature sensor 17, the atmospheric pressure sensor 18, and ECU19 which is a control apparatus are comprised.

  The intake device 3 includes a compressor 27 of the supercharger 4, an air supply pipe 5, an intercooler 6, and an air supply manifold 7.

  The supercharger 4 compresses and compresses intake air using the exhaust pressure of the exhaust as a drive source. The supercharger 4 includes a compressor 27 and a turbine 24. The compressor 27 compresses and compresses intake air. The intercooler 6 is connected to the compressor 27 via the air supply pipe 5.

  The intercooler 6 cools the pressurized intake air. The intercooler 6 cools the supply air by performing heat exchange between cooling water supplied by a cooling water pump (not shown) and pressurized intake air (hereinafter, the pressurized intake air is referred to as supply air). . The intercooler 6 is connected to an air supply manifold 7.

  The air supply manifold 7 distributes the air supply to each cylinder 1 a of the engine 1. The air supply manifold 7 is connected to each cylinder 1 a, 1 b, 1 c, 1 d of the engine 1. The air supply manifold 7 is configured to be able to supply air that has been cooled by the intercooler 6 to the cylinders 1 a, 1 b, 1 c, and 1 d of the engine 1.

  The exhaust device 8 includes an exhaust manifold 9, an exhaust pipe 10, and a turbine 24 of the supercharger 4.

  The exhaust manifold 9 is a pipe for collecting exhaust from the cylinders and exhausting them. The exhaust manifold 9 is connected to the cylinders 1 a, 1 b, 1 c, and 1 d of the engine 1.

  The turbine 24 of the supercharger 4 generates rotational power by the exhaust pressure. The turbine 24 is connected to the exhaust manifold 9 via the exhaust pipe 10. The turbine 24 communicates with the outside.

  As described above, in the intake device 3, the compressor 27, the air supply pipe 5, the intercooler 6, and the air supply manifold 7 of the supercharger 4 are sequentially connected from the upstream side (external). Further, in the exhaust device 8, the exhaust manifold 9, the exhaust pipe 10, and the turbine 24 of the supercharger 4 are connected in order from the upstream side (engine 1).

  In the intake device 3, external air (intake air) is sucked and pressurized and compressed by the compressor 27 of the supercharger 4. At this time, the intake air is pressurized and compressed, so that compression heat is generated and the temperature rises. The intake air compressed and compressed by the compressor 27 is discharged from the supercharger 4 as supply air.

  The supply air discharged from the supercharger 4 is supplied to the intercooler 6 via the supply pipe 5. The supply air supplied to the intercooler 6 is supplied to the engine 1 via the supply manifold 7 after being cooled.

  In the exhaust device 8, the exhaust from the engine 1 is supplied to the turbine 24 of the supercharger 4 through the exhaust manifold 9. The turbine 24 is rotated by exhaust. The rotational power of the turbine 24 is transmitted to the compressor 27. Exhaust gas supplied to the turbine 24 is discharged to the outside through the exhaust pipe 10 and a purification device (not shown).

  The engine rotation speed detection sensor 11 detects an engine rotation speed En that is the rotation speed of the engine 1. The engine rotation speed detection sensor 11 includes a sensor and a pulser, and is provided on the output shaft of the engine 1. In the present embodiment, the engine rotation speed detection sensor 11 is composed of a sensor and a pulser, but any sensor that can detect the engine rotation speed En may be used.

  The injection amount detection sensor 12 detects an injection amount F of fuel injected from the fuel injection valve 2. The injection amount detection sensor 12 is provided in the middle of a fuel supply pipe (not shown). The injection amount detection sensor 12 is composed of a flow rate sensor. In the present embodiment, the injection amount detection sensor 12 is constituted by a flow rate sensor, but the present invention is not limited to this, and any device that can detect the fuel injection amount F may be used.

  The crank angle detection sensor 13 detects a crank angle θ (not shown). The crank angle detection sensor 13 is provided in the vicinity of a crankshaft (not shown).

  The intake flow rate detection sensor 14 detects the average intake flow rate If. The intake flow rate detection sensor 14 is provided on the upstream side of the supercharger 4. As the intake flow rate detection sensor 14, a thermal mass flow meter is generally used that calculates the flow rate by measuring the amount of heat taken away by the fluid. In the present embodiment, the intake flow rate detection sensor 14 is constituted by a thermal mass flow meter. However, the present invention is not limited to this, and any device that can detect the intake flow rate may be used.

  The supercharging pressure detection sensor 15 detects the average supercharging pressure Ip of the intake air pressurized by the supercharger. The supercharging pressure detection sensor 15 is provided in the intake manifold. The supercharging pressure detection sensor 15 is composed of an electric pressure sensor.

  The supercharger rotational speed detection device 16 detects an average supercharger rotational speed Tn. The supercharger rotation speed detection device 16 is provided in the compressor 27 or the turbine 24 of the supercharger. The supercharger rotation speed detection device 16 is configured to detect an eddy current generated by the compressor 27 or the blade of the turbine 24 passing through a detection range, or to detect an induced electromotive force.

  The ECU 19 controls the engine 1. Various programs and data for controlling the engine 1 are stored in the ECU 19. The ECU 19 may be configured such that a CPU, ROM, RAM, HDD, and the like are connected by a bus, or may be configured by a one-chip LSI or the like.

  The ECU 19 is connected to the engine rotation speed detection sensor 11 and can acquire the engine rotation speed En detected by the engine rotation speed detection sensor 11.

  The ECU 19 is connected to the fuel injection valve 2 and can control the fuel injection valve 2.

  The ECU 19 is connected to the injection amount detection sensor 12 and can acquire the injection amount F detected by the injection amount detection sensor 12.

  The ECU 19 is connected to the crank angle detection sensor 13 and acquires the crank angle θ detected by the crank angle detection sensor 13, that is, the intake stroke, compression stroke, combustion stroke and exhaust stroke timing of each cylinder 1a, 1b, 1c, 1d. Is possible.

  The ECU 19 is connected to the intake flow rate detection sensor 14 and can acquire the average intake flow rate If during the time Ta detected by the intake flow rate detection sensor 14.

  The ECU 19 is connected to the supercharging pressure detection sensor 15 and can acquire the average supercharging pressure Ip during the time Ta detected by the supercharging pressure detection sensor 15.

  The ECU 19 is connected to the supercharger rotation speed detection device 16 and can acquire the average supercharger rotation speed Tn and the blade detection frequency Bn calculated by the supercharger rotation speed detection device 16.

  The ECU 19 is connected to the outside air temperature sensor 17 and the atmospheric pressure sensor 18 and can acquire the outside air temperature Bt and the atmospheric pressure Bp detected by the outside air temperature sensor 17 and the atmospheric pressure sensor 18.

  As shown in FIG. 2, the ECU 19 stores a supercharger rotation speed map M1 showing the relationship among the average intake flow rate If, the average supercharging pressure Ip, and the average supercharger rotation speed Tn under a predetermined condition. . Further, the ECU 19 stores a correction coefficient map M2 in which the influence of the outside air temperature Bt and the atmospheric pressure Bp on the average supercharger rotation speed Tn is indicated by a correction coefficient K. The ECU 19 can calculate the estimated average supercharger rotational speed ETn from the supercharger rotational speed map M1 based on the acquired average intake air flow If and average supercharging pressure Ip. Further, the ECU 19 can calculate the correction coefficient K from the correction coefficient map M2 based on the acquired outside air temperature Bt and atmospheric pressure Bp. Then, the ECU 19 can calculate a corrected average supercharger rotational speed RTn in consideration of the influence of the outside air temperature Bt and the atmospheric pressure Bp from the calculated estimated average supercharger rotational speed ETn and the correction coefficient K.

  Below, the supercharger 4 which concerns on one Embodiment of this invention is demonstrated in detail using FIG.

  As shown in FIG. 3, the supercharger 4 supplies the engine 1 with intake air that has been compressed and compressed using the exhaust pressure of the exhaust discharged from the engine 1 (see FIG. 1) as a drive source. The supercharger 4 includes a connecting portion 20, a turbine 24, a compressor 27, and the like.

  The connecting part 20 connects the turbine 24 and the compressor 27. The connecting portion 20 includes a center housing 21, a connecting shaft 22, a bearing 23, and the like. The center housing 21 has a turbine 24 connected to one side and a compressor 27 connected to the other side. The connecting shaft 22 connects a turbine wheel 26 described later and a compressor wheel 29 described later. The connecting shaft 22 is rotatably supported by the center housing 21 via a bearing 23.

  The turbine 24 converts the exhaust pressure of the engine 1 into a rotational driving force. The turbine 24 includes a turbine casing 25, a turbine wheel 26, and the like.

  The turbine casing 25 is a member formed in a bottomed cylindrical shape. One side (bottom side) of the turbine casing 25 is connected to the center housing 21. On one side of the turbine casing 25, an exhaust supply path 25a is formed in which exhaust gas is supplied to the outer peripheral portion. On the other side (the bottom side) of the turbine casing 25, an exhaust outlet 25b is formed. A connecting shaft 22 communicates with the bottom of the turbine casing 25. The exhaust supply path 25 a of the turbine casing 25 is formed so as to communicate with the inside of the turbine casing 25.

  The turbine wheel 26 includes a turbine hub 26a that is a base portion of the turbine wheel 26, and a plurality of turbine blades 26b that are arranged on the outer circumferential surface 26c of the turbine hub 26a at equal intervals in the circumferential direction. The turbine wheel 26 has a turbine hub 26a fixed to the connecting shaft 22 and is rotatably supported. The turbine hub 26 a has an outer peripheral surface 26 c on the side opposite to the connecting shaft 22 that is parallel to the axis of the connecting shaft 22, and the diameter of the turbine hub 26 a is increased while curving toward the connecting shaft 22. A flange 26d is formed in a direction perpendicular to the axial center.

  In the turbine wheel 26, the outer periphery of the flange 26 d (expansion side) of the turbine hub 26 a faces the exhaust supply path 25 a of the turbine casing 25, and the end on the diameter reduction side of the turbine hub 26 a is connected to the discharge port 25 b of the turbine casing 25. It arrange | positions inside the turbine casing 25 so as to oppose. In other words, the turbine wheel 26 is arranged such that the diameter of the turbine hub 26a decreases from the exhaust supply side toward the exhaust side. With this configuration, the turbine wheel 26 is rotated by the exhaust pressure of the supplied exhaust gas, and the exhaust gas is guided by the outer peripheral surface 26c of the turbine hub 26a in a direction parallel to the rotation axis and discharged from the discharge port 25b. Let

  The compressor 27 compresses and compresses the supply air of the engine 1. The compressor 27 includes a compressor casing 28, a compressor wheel 29, and the like.

  The compressor casing 28 is a member formed in a cylindrical shape. One side of the compressor casing 28 is connected to the center housing 21 to form a bottom portion. A connecting shaft 22 is communicated with a bottom portion constituted by the center housing 21. On one side (bottom side) of the compressor casing 28 is formed an intake air discharge path 28a through which the intake air is discharged to the outer periphery. An intake air supply port 28 b is formed on the other side (the opposite bottom side) of the compressor casing 28. An inner wall 28c of the compressor casing 28 is formed so as to increase in diameter toward one side and communicated with the intake air discharge passage 28a.

  The compressor wheel 29 includes a compressor hub 29a constituting the base of the compressor wheel 29, a plurality of full blades 29b (all blades) and splitter blades alternately arranged at equal intervals in the outer circumferential surface 29d of the compressor hub 29a. 29c (short wing).

  The compressor wheel 29 has a compressor hub 29a fixed to the connecting shaft 22 and is rotatably supported. That is, the compressor wheel 29 is configured to be able to transmit the rotational power from the turbine wheel 26 via the connecting shaft 22. The compressor hub 29a expands in diameter while an outer peripheral surface 29d on the side of the anti-connection shaft 22 parallel to the axis of the connection shaft 22 is curved toward the connection shaft 22 side, and is connected to the end of the connection shaft 22 on the connection shaft 22 side. A flange 29e is formed in a direction perpendicular to the axis of the. The outer edge shapes of the full blade 29b (all blades) and the splitter blade 29c (short blade) are formed along the inner wall 28c of the compressor casing 28 so as to form a minute gap. Further, the end portion on the diameter reduction side of the splitter blade 29c is arranged on the diameter expansion side with respect to the end portion on the diameter reduction side of the full blade 29b. The compressor wheel 29 may not have the splitter blade 29c.

  In the compressor wheel 29, the outer periphery of the flange 29e (expansion side) of the compressor hub 29a faces the intake air discharge passage 28a of the compressor casing 28, and the end portion on the reduced diameter side of the compressor hub 29a is the intake supply port of the compressor casing 28 It arrange | positions inside the compressor casing 28 so as to oppose 28b. That is, the compressor wheel 29 is arranged such that the compressor hub 29a increases in diameter from the intake supply side to the discharge side. At this time, the interval between the inner wall 28c of the compressor casing 28 and the compressor hub 29a is configured to become narrower as it approaches the intake air discharge passage 28a. That is, in the compressor casing 28, an intake compression passage 29f is constituted by a space surrounded by the inner wall 28c of the compressor casing 28, the full blade 29b, the splitter blade 29c, and the outer peripheral surface 29d. The compressor wheel 29 includes a full blade 29b or a splitter blade 29c to form a first blade B11 and a second blade B12.

  As described above, in the supercharger 4, when the exhaust gas is supplied to the turbine 24, the turbine wheel 26 is rotated by the exhaust pressure. The compressor wheel 29 connected to the turbine wheel 26 is rotated by the rotational driving force of the turbine wheel 26. The compressor wheel 29 takes in the intake air from the intake air supply port 28b. The taken-in intake air is discharged to the intake air discharge passage 28a by the compressor wheel 29 via the intake air compression passage 29f. At this time, the intake air is pressurized and compressed in the intake compression passage 29f, and compression heat is generated.

  Next, the supercharger rotation speed detection device 16 according to an embodiment of the present invention will be described in detail with reference to FIGS. 3 and 4. In the present embodiment, the supercharger rotational speed detection device 16 detects the rotational speed of the compressor 27, but is not limited thereto, and may be configured to detect the rotational speed of the turbine 24. .

  As shown in FIGS. 3 and 4, the supercharger rotation speed detection device 16 detects the rotation speed of the compressor 27. The supercharger rotation speed detection device 16 includes a detection unit 30, an amplifier 31, a controller 32, and the like. The supercharger rotation speed detection device 16 detects the rotation speed of the compressor 27 by detecting the full blade 29 b and the splitter blade 29 c by the detection unit 30.

  The detection unit 30 detects the full blade 29b and the splitter blade 29c. The detection unit 30 is inserted and attached to an insertion hole 10 d formed on the intake supply port 28 b side of the compressor casing 28. At this time, the detection unit 30 is arranged so that the tip thereof does not protrude from the inner wall 28 c of the compressor casing 28. The detection unit 30 includes a coil (not shown) that generates a magnetic field inside a substantially cylindrical casing. When the full blade 29b or the splitter blade 29c passes through the magnetic field generated from the coil, the magnetic flux penetrates the full blade 29b or the splitter blade 29c, and an eddy current is generated. The detection unit 30 detects the impedance of the coil that changes due to the eddy current and outputs a detection signal. Accordingly, the detection unit 30 determines that the full blade 29b or the splitter blade 29c has passed near the detection unit 30.

  In order to detect the full blade 29b and the splitter blade 29c having different shapes, the detection unit 30 must be arranged so that both the full blade 29b and the splitter blade 29c pass the magnetic field. Therefore, as shown in FIG. 4, it is necessary to arrange the detection unit 30 so that the region A in which the full blade 29 b and the splitter blade 29 c are both close to the compressor casing 28 is included in the magnetic field range. is there. In the present embodiment, the supercharger rotation speed detection device 16 detects an eddy current, but is not limited to this, and may detect an induced electromotive force.

  The amplifier 31 amplifies the signal from the detection unit 30. The amplifier 31 is connected to the detection unit 30 and acquires a signal from the detection unit 30. The amplifier 31 amplifies the signal from the detection unit 30 and transmits it to the controller 32.

  The controller 32 calculates the rotational speed of the compressor 27. The controller 32 stores various programs and data for processing the amplified signal from the amplifier 31. Specifically, the supercharger rotation speed detection device 16 may have a configuration in which a CPU, a ROM, a RAM, an HDD, and the like are connected by a bus, or may be configured by a one-chip LSI or the like. Good.

  The controller 32 stores data on the diameter D of a detection region B of the detection unit 30 in which the magnetic flux density from the coil is high enough to generate a detectable eddy current. The controller 32 stores data on the blade interval S of the compressor 27 blades. The controller 32 is connected to the amplifier 31 and can acquire an amplified signal from the amplifier 31. The controller 32 calculates the rotation speed of the compressor 27 using the amplified signal from the amplifier 31. The controller 32 is connected to the ECU 19 that is a control device of the engine 1 and is capable of transmitting an amplified signal from the amplifier 31 that has undergone predetermined processing to the ECU 19 (see FIG. 1).

  Next, using FIG. 5, the detection unit 30 of the supercharger rotation speed detection device 16 calculates the detection mode and the average supercharger rotation speed Tn of the first blade B11 composed of the full blade 29b or the splitter blade 29c. The aspect to perform is demonstrated concretely. In FIG. 5, a range indicated by a two-dot chain line indicates a detection region B of the detection unit 30. The supercharger rotation speed detection device 16 is configured such that the full blade 29b or the splitter blade 29c when the distance from the center of the detection region B of the inspection unit 13 is equal to or less than a predetermined radius D / 2. Eddy current generated in

  As shown in FIG. 5A, in the detection unit 30, when the first blade Bl1 enters from the counter-rotation direction side of the detection region B, the magnetic flux penetrates the first blade Bl1 at that moment and the eddy current flows. Will occur. Therefore, the detection unit 30 detects a change in the impedance of the coil caused by the influence of the eddy current. Accordingly, the detection unit 30 outputs a detection signal at time T11 on the assumption that the side surface on the rotation direction side of the first blade Bl1 has reached the vicinity of the detection unit 30.

  As shown in FIG. 5B, in the detection unit 30, when the part of the first blade Bl1 that has finally entered the detection area B into the detection area B comes off from the rotation direction side of the detection area B, the first blade In Bl1, no magnetic flux penetrates, so no eddy current is generated. Therefore, the detection unit 30 does not detect a change in the impedance of the coil caused by the influence of the eddy current. Accordingly, the detection unit 30 stops outputting the detection signal on the assumption that the side surface on the counter-rotation direction side of the first blade B11 has passed near the detection unit 30.

In this way, the supercharger rotational speed detection device 16 detects that the first blade Bl1 is in the counter-rotation direction side from the time T11 when the side surface on the rotation direction side of the first blade Bl1 enters the counter-rotation direction side of the detection region B. A detection signal is output until the side surface of the detection area B comes off from the rotation direction side of the detection region B.
Similarly, the supercharger rotation speed detection device 16 detects the second blade Bl2, the third blade Bl3, the fourth blade Bl4,... Of the compressor wheel 29 composed of the full blade 29b or the splitter blade 29c. Do.

  Further, as shown in FIG. 6, the supercharger rotational speed detection device 16 is configured to perform blade detection for a predetermined number of times Na (11 in the present embodiment) from time T11 when the side surface of the first blade Bl1 is detected in the rotational direction. The time Ta until the detection is detected. Then, the supercharger rotation speed detection device 16 calculates the average supercharger rotation speed Tn from the number of detections Na, the blade interval S, and the time Ta.

  Next, abnormality determination of the supercharger rotation speed detection device 16 in the engine 1 according to the present invention will be described.

  The ECU 19 calculates an estimated average supercharger rotational speed ETn from the supercharger rotational speed map M1 based on the average intake air flow If and the average supercharging pressure Ip during the time Ta. In addition, the ECU 19 calculates a correction coefficient K from the correction coefficient map M2 based on the acquired outside air temperature Bt and atmospheric pressure Bp. Then, the ECU 19 calculates a corrected average supercharger rotation speed RTn in consideration of the influence of the outside air temperature Bt and the atmospheric pressure Bp from the calculated estimated average supercharger rotation speed ETn and the correction coefficient K. At the same time, the ECU 19 obtains an average supercharger rotation speed Tn calculated from the time Ta, the blade interval S, and the detection number Na for which the supercharger rotation speed detection device 16 detects the blades by the detection number Na.

  If the ECU 19 determines that the difference between the calculated corrected average supercharger rotational speed RTn and the average supercharger rotational speed Tn exceeds the threshold δ, an abnormality has occurred in the supercharger rotational speed detection device 16. Assuming that the corrected average supercharger rotational speed RTn calculated in consideration of the influence of the outside air temperature Bt and the atmospheric pressure Bp is the average supercharger rotational speed Tn.

  Next, abnormality determination of the supercharger rotation speed detection device 16 in the engine 1 according to the present invention will be specifically described with reference to FIG.

  As shown in FIG. 7, in step S110, the ECU 19 acquires the outside air temperature Bt from the outside air temperature sensor 17, acquires the atmospheric pressure Bp from the atmospheric pressure sensor 18, and moves the step to step S120.

  In step S120, the ECU 19 obtains the average intake air flow If during the time Ta from the intake air flow detection sensor 14, obtains the average supercharging pressure Ip during the time Ta from the supercharging pressure detection sensor 15, and moves the step to step S130. Transition.

  In step S130, the ECU 19 calculates an estimated average supercharger rotational speed ETn from the supercharger rotational speed map M1 based on the acquired average intake air flow If and average supercharging pressure Ip, and the process proceeds to step S140. .

  In step S140, the ECU 19 calculates a correction coefficient K from the correction coefficient map M2 based on the acquired outside air temperature Bt and atmospheric pressure Bp, and moves the step to step S150.

  In step S150, the ECU 19 calculates a corrected average supercharger rotation speed RTn from the calculated estimated average supercharger rotation speed ETn and the correction coefficient K, and the process proceeds to step S160.

  In step S160, the ECU 19 obtains an average supercharger rotation speed Tn calculated from the time Ta, the blade interval S, and the detection number Na that the supercharger rotation speed detection device 16 detects the blades by the number of detections Na. The process proceeds to step S170.

In step S170, the ECU 19 determines whether or not the absolute value of the difference between the calculated corrected average supercharger rotational speed RTn and the average supercharger rotational speed Tn is less than the threshold δ.
As a result, when it is determined that the absolute value of the difference between the calculated corrected average supercharger rotation speed RTn and the average supercharger rotation speed Tn is less than the threshold δ, the ECU 19 shifts the step to step S180.
On the other hand, when it is determined that the absolute value of the difference between the calculated corrected average supercharger rotational speed RTn and the average supercharger rotational speed Tn is not less than the threshold δ, the ECU 19 proceeds to step S280. In this embodiment, the determination is made using the absolute value of the difference between the corrected average supercharger rotational speed RTn and the average supercharger rotational speed Tn, but the present invention is not limited to this, and the corrected average supercharger is not limited thereto. It may be a ratio between the rotational speed RTn and the average supercharger rotational speed Tn.

  In step S180, the ECU 19 outputs the average supercharger rotation speed Tn acquired from the supercharger rotation speed detection device 16 by the supercharger, and shifts the step to step 110.

  In step S280, the ECU 19 determines that an abnormality has occurred in the supercharger rotation speed detection device 16, and the supercharger calculates the corrected average supercharge calculated from the supercharger rotation speed map M1 and the correction coefficient map M2. The machine rotation speed RTn is output, and the step proceeds to step 110.

  By configuring as described above, the engine 1 uses the estimated average supercharger rotation speed calculated from the supercharger rotation speed map M1 based on the average intake air flow If and the average supercharging pressure Ip in the ECU 19 as the outside air temperature Bt. By correcting with the atmospheric pressure Bp, a corrected average supercharger rotational speed RTn considering the operating environment of the engine 1 is calculated. Further, when the ECU 19 determines that the supercharger rotation speed detection device 16 is abnormal in the ECU 19, the engine 1 performs various controls assuming that the supercharger is rotating at the corrected average supercharger rotation speed RTn. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

  Next, calculation of the average intake flow rate in the engine 1 according to the present invention will be described with reference to FIGS. 6 and 8.

  As shown in FIG. 6, the ECU 19 calculates an average supercharger rotation speed Tn from the time Ta, the blade interval S, and the time Ta for which the supercharger rotation speed detection device 16 detects the blades by the number of times of detection Na. (See FIG. 5). Then, the ECU 19 calculates an estimated average intake air flow rate EIf from the supercharger rotation speed map M1 based on the acquired average supercharging pressure Ip and average supercharger rotation speed Tn during the time Ta.

  Further, as shown in FIG. 8, the ECU 19 obtains the intake stroke period of each cylinder from the crank angle obtained from the crank angle detection sensor. The ECU 19 acquires the blade detection number Nb1 detected by the supercharger rotation speed detection device 16 during the intake stroke period Ti1 of the first cylinder 1a. Similarly, the ECU 19 detects the number of blade detections Nb1 detected by the supercharger rotation speed detection device 16 during the intake stroke period Ti2 of the second cylinder 1b, and the supercharger rotation speed during the intake stroke period Ti3 of the third cylinder 1c. The blade detection number Nb3 detected by the detection device 16 and the blade detection number Nb4 detected by the supercharger rotation speed detection device 16 in the intake stroke period Ti4 of the fourth cylinder 1d are acquired. The ECU 19 calculates the distribution ratios R1, R2, R3, and R4 of the intake air that is sucked into the first cylinder from the ratios of the acquired detection number Nb1, detection number Nb2, detection number Nb3, and detection number Nb4.

  With the configuration as described above, the engine 1 operates the engine 1 by calculating the intake air flow rate from the average turbocharger rotational speed Tn acquired from the supercharger rotational speed detection device 16 and the supercharger rotational speed map M1. The estimated average intake air flow rate EIf according to the environment and conditions is estimated. Further, the engine 1 uses the distribution ratios R1, R2, R3, and R4 calculated by the ECU 19, and each cylinder 1a, 1b, calculated from the average intake flow rate If detected by the flow rate detection sensor 14 or the estimated average intake flow rate EIf. The fuel injection amount is corrected for each cylinder based on the intake air amounts 1c and 1d. Thereby, it is possible to calculate an appropriate supercharger rotation speed regardless of the operating environment and operating conditions, and to perform appropriate control in combination with other measurement results.

  Further, the rotational speed of the compressor 27 having a mass sufficiently smaller than the mass of the engine 1 varies more sensitively than the engine rotational speed En of the engine 1 when the fuel injection amount F varies. Therefore, the engine 1 can perform the injection amount correction that corrects the fuel injection amount F from the average supercharger rotational speed Tn that has fluctuated due to the minute injection of fuel. Specifically, as shown in FIG. 9, the ECU 19 calculates the actual fuel injection amount Q1 at the target valve opening time TQt from the average supercharger rotation speed Tn acquired from the supercharger rotation speed detection device 16. Then, the ECU 19 corrects the valve opening time TQ of the fuel injection valve 2 to the valve opening time TQr so that the actual fuel injection amount Q1 (two-dot chain line in FIG. 9) becomes the target injection amount Qt (solid line in FIG. 9). . Thereby, even in the large engine 1 having a large mass, the injection amount correction by the micro injection can be more accurately performed by using the average supercharger rotation speed Tn.

DESCRIPTION OF SYMBOLS 1 Engine 4 Supercharger 14 Intake flow rate detection sensor 15 Supercharging pressure detection sensor If Average intake flow rate Ip Average supercharging pressure M1 Supercharger rotational speed map Tn Average supercharger rotational speed ETn Estimated average supercharger rotational speed RTn correction Average turbocharger speed Bt Outside temperature Bp Atmospheric pressure

Claims (5)

A turbocharged engine,
A turbocharger rotation speed map showing the relationship between the average intake flow rate, average boost pressure, and average turbocharger rotation speed is provided, and the average intake flow rate detected by the intake flow rate detection sensor and the average excess pressure detected by the boost pressure detection sensor are provided. An engine that calculates a corrected average supercharger rotation speed obtained by correcting an estimated average supercharger rotation speed calculated from a supercharger rotation speed map based on a supply pressure with an outside air temperature and an atmospheric pressure.   A turbocharger rotation speed detection device that calculates a turbocharger rotation speed by detecting a compressor or turbine blade of the turbocharger, and an average turbocharger rotation speed of the turbocharger calculated by the rotation speed detection device 2. The engine according to claim 1, wherein an estimated average intake air flow rate is calculated from the supercharger rotation speed map on the basis of the supercharging pressure and the average value of the supercharging pressure.   3. The engine according to claim 2, wherein the distribution ratio of the intake air of each cylinder is calculated from the number of detections of the compressor or turbine blade of the supercharger detected by the supercharger rotation speed detection device during the intake stroke of each cylinder. .   If the difference or ratio between the average supercharger rotational speed and the corrected supercharger rotational speed exceeds a threshold, it is determined that an abnormality has occurred in the supercharger rotational speed detection device, and the corrected supercharger rotational speed The engine according to claim 2 or 3, wherein is a supercharger rotational speed.   5. The fuel injection amount is corrected from the change amount of the intake flow rate or the change amount of the estimated intake flow rate detected by the intake flow rate sensor when fuel is injected based on an arbitrary target injection amount. The engine according to any one of the above.

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