JP2005113690A - Control device for internal combustion engine for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for an internal combustion engine for a vehicle capable of ensuring both engine output and negative pressure in a balanced manner.
The present invention relates to a control apparatus for an internal combustion engine for a vehicle (1) provided with a supercharger (10) that can be driven by an electric motor (10b) on an intake passage (2), on the upstream side of the supercharger (10) in the intake passage (2). A bypass passage 20 that bypasses the downstream side, a bypass valve 22 that is disposed on the bypass passage 20 and adjusts an intake air amount that passes through the bypass passage 20, a control means 11 that controls the motor 10b and the bypass valve 22, and an intake air A negative pressure lead-out path 31 connected to the upstream side of the supercharger 10 in the passage 2 (or upstream side of the bypass valve 22 in the bypass path 20) is provided.
[Selection] Figure 1

Description

  The present invention relates to a control device for an internal combustion engine for a vehicle that can secure negative pressure used for various controls of the vehicle while suppressing a decrease in engine output.

  Negative pressure is used to control the internal combustion engine. For example, in an internal combustion engine, negative pressure is used for introducing fuel evaporated in a fuel tank into an intake passage, driving various control valves associated with the internal combustion engine, or the like. Negative pressure is also used for a brake booster for a vehicle equipped with an internal combustion engine. In the device described in [Patent Document 1], a negative pressure generated downstream of the throttle valve on the intake passage is used, and a turbocharger disposed on the upstream side of the throttle valve is controlled to perform brake multiplication. The purpose is to supply a stable negative pressure to the force device.

If supercharging is performed by a turbocharger located upstream of the throttle valve, the pressure in the intake pipe on the downstream side of the throttle valve increases and the negative pressure becomes insufficient (or becomes positive). Therefore, in the device described in [Patent Document 1], the turbocharger is a variable nozzle type, and the supercharging effect is intentionally suppressed by adjusting the opening degree of the variable nozzle during supercharging, which is necessary instead. Negative pressure is secured.
JP 2000-282906 A

  However, in the control in the apparatus described in [Patent Document 1], the effect of supercharging is sacrificed in order to secure negative pressure, and sufficient engine output may not be obtained. Accordingly, an object of the present invention is to provide a control device for an internal combustion engine for a vehicle that can achieve both balanced engine output and negative pressure in a balanced manner.

  The invention according to claim 1 is a control device for an internal combustion engine for a vehicle having a supercharger that can be driven by an electric motor on an intake passage, and bypasses the upstream side and the downstream side of the supercharger in the intake passage. Bypass path, a bypass valve arranged on the bypass path to adjust the intake air amount passing through the bypass path, a control means for controlling the motor and the bypass valve, and an upstream side of the supercharger in the intake path or bypass A negative pressure lead-out path connected to the upstream side of the bypass valve in the path is provided.

  According to a second aspect of the present invention, there is provided the control apparatus for an internal combustion engine for a vehicle according to the first aspect, wherein the negative pressure tank connected to the negative pressure derivation path and the pressure in the tank for detecting the pressure in the negative pressure tank Detection means, and the control means increases the drive amount of the motor and opens the bypass valve when the pressure in the tank detected by the tank pressure detection means exceeds a predetermined reference pressure. It is characterized by narrowing the degree. Narrowing the opening of the bypass valve includes making the opening fully closed.

  According to a third aspect of the present invention, in the control device for an internal combustion engine for a vehicle according to the second aspect of the present invention, the control device further includes a supercharging necessity determination means for determining whether the internal combustion engine is supercharged. When it is determined that supercharging is not required by the non-determining means, the reference pressure is set lower than when supercharging is determined to be necessary. Here, the pressure is described (considered) as an absolute pressure (since the vacuum is zero, so-called negative pressure also takes a positive value as a numerical value). same as below.

  According to a fourth aspect of the present invention, in the control device for an internal combustion engine for a vehicle according to any one of the first to third aspects, the connection between the upstream connection portion to the intake passage of the bypass passage and the supercharger. An adjustment valve that adjusts the amount of intake air that passes through the intake passage is further provided on the intake passage, and the negative pressure derivation path is connected to the intake passage between the turbocharger and the adjustment valve. It is said.

  According to a fifth aspect of the present invention, there is provided the control apparatus for an internal combustion engine for a vehicle according to the fourth aspect, wherein the negative pressure tank connected to the negative pressure derivation path and the tank for detecting the pressure in the negative pressure tank And further comprising a pressure detection means, and the control means increases the drive amount of the electric motor when the pressure in the tank detected by the pressure detection means in the tank exceeds a predetermined reference pressure, and the adjustment valve It is characterized by narrowing the opening degree of. Narrowing the opening of the adjustment valve includes making the opening fully closed.

  According to the control apparatus for an internal combustion engine for a vehicle according to claim 1, since the negative pressure generated in the intake passage or the bypass passage due to supercharging is used, securing of engine output by supercharging, It is possible to achieve both the securing of the negative pressure generated by feeding. At this time, since the supercharger can adjust the amount of supercharging by the electric motor and the amount of intake air via the bypass passage can be adjusted by the bypass valve, it is possible to balance engine output and negative pressure in a balanced manner. is there.

  According to the control apparatus for an internal combustion engine for a vehicle according to claim 2, by storing the negative pressure in the negative pressure tank, the frequency of generating the negative pressure can be reduced, and the influence on the engine output can be reduced. it can. Also, at this time, negative pressure is effectively generated according to the pressure in the negative pressure tank (that is, the amount of intake air passing through the bypass passage by increasing the drive amount of the motor and reducing the opening of the bypass valve) Therefore, an optimal negative pressure (pressure less than the reference pressure) can always be ensured.

  According to the control apparatus for an internal combustion engine for a vehicle according to claim 3, when supercharging is required (that is, when further engine output is required), the reference pressure (absolute pressure) is higher than when supercharging is not required. ) Is set high, the frequency with which negative pressure is generated when supercharging is required can be reduced, and the effect on engine output can be reduced. In other words, when supercharging is not required (that is, no further engine output is required), the negative pressure can be ensured by setting the reference pressure (absolute pressure) lower than when supercharging is required. Can be generated.

  According to the control apparatus for an internal combustion engine for a vehicle according to claim 4, the intake air amount that passes through the intake passage is adjusted on the intake passage between the upstream connection portion to the intake passage of the bypass passage and the supercharger. By further disposing the adjusting valve, the negative pressure can be generated more effectively, and the degree of freedom in controlling the negative pressure and the amount of intake air supplied to the internal combustion engine can be increased.

  According to the control device for an internal combustion engine for a vehicle according to claim 5, by storing the negative pressure in the negative pressure tank, the frequency of generating the negative pressure can be reduced, and the influence on the engine output can be reduced. it can. At this time, the negative pressure is effectively generated according to the pressure in the negative pressure tank (that is, the drive amount of the electric motor is increased, and the opening of the adjustment valve is narrowed so that the negative pressure is easily generated). Therefore, it is possible to always ensure an optimum negative pressure (pressure less than the reference pressure).

  An embodiment of the control device of the present invention will be described below. An engine 1 having a control device of the present embodiment is shown in FIG.

  An engine (internal combustion engine) 1 described in the present embodiment is a multi-cylinder engine, but only one cylinder is shown in FIG. 1 as a cross-sectional view. In the engine 1, the intake air taken in through the intake passage 2 is mixed with the fuel injected from the injector 4 immediately before the cylinder 3 to form an air-fuel mixture. The air-fuel mixture is sucked into the cylinder 3, compressed by the piston 5, ignited by the spark plug 6, and burned. At this time, the pressure in the cylinder 3 rises due to combustion, and the piston 5 is reciprocated, and this reciprocating motion is converted into a rotational motion by the connecting rod and taken out as an output. An intake valve 7 opens and closes the inside of the cylinder 3 and the intake passage 2. The exhaust gas after combustion is exhausted to the exhaust passage 8. An exhaust valve 9 opens and closes the inside of the cylinder 3 and the exhaust passage 8.

  The engine 1 has a turbo unit (supercharger) 10. In the turbo unit 10, a compressor wheel disposed on the intake passage 2 and a turbine wheel disposed on the exhaust passage 8 are connected by the same rotation shaft (hereinafter, this portion is simply referred to as a turbine / compressor 10a). . The turbo unit of the present embodiment incorporates a motor (electric motor) 10b so that the rotating shaft serves as an output shaft. That is, the turbo unit 10 of this embodiment is a turbocharger with an electric motor.

  The turbo unit 10 can function as a normal supercharger that performs supercharging with the energy (exhaust energy) of the exhaust flow, but forcibly drives the turbine / compressor 10a with electric energy supplied from the battery. It is possible to carry out further supercharging. Further, by using the exhaust energy, the motor 10b can be rotated through the turbine / compressor 10a to generate regenerative power, and the generated power can be recovered. The motor 10b has a rotor fixed to the rotating shaft of the turbine / compressor 10a and a stator disposed around the rotor as main components.

  The motor 10 b is connected to a controller 12, and an electronic control unit (ECU) 11 that controls the entire engine 1 and a battery 13 are connected to the controller 12. In the motor 10b, the applied electric power and the like are controlled by the ECU 11 and the controller 12, and thereby the rotational speed control, that is, the supercharging pressure control is performed. At the time of supercharging pressure control, the detection results of the air flow meter 14 disposed upstream of the turbo unit 10 on the intake passage 2 and the pressure sensor 15 disposed in the surge tank on the intake passage 2 are used. Is done. The air flow meter 14 of the present embodiment is of a hot wire type and detects an intake air amount as a mass flow rate. The air flow meter 14 also includes a thermistor type intake air temperature sensor, and the air flow meter 14 also has a function as an intake air temperature sensor.

  The controller 12 not only controls the drive of the motor 10b, but also has a function as an inverter that performs voltage conversion of electric power regenerated by the motor 10b. The motor 10b can also detect the rotation speed by a mechanism that controls the rotation speed. An intercooler 16 is disposed downstream of the turbo unit 10 on the intake passage 2. A bypass path 20 that bypasses the intake path 2 is provided between the upstream side and the downstream side of the turbo unit 10 (the downstream side is upstream of the intercooler 16). A bypass valve 22 that adjusts the amount of intake air that passes through the bypass path 20 is disposed on the bypass path 20.

  The opening degree of the bypass valve 22 is adjusted by the motor 23. An opening degree sensor 24 that detects the opening degree is also provided along with the bypass valve 22. The motor 23 is connected to the ECU 11 and is driven by a drive signal from the ECU 11 to change the opening degree of the bypass valve 22. The opening sensor 24 is also connected to the ECU 11, and the detection result of the opening sensor 24 is used during the opening adjustment control of the bypass valve 22.

  Further, an adjustment valve 29 for adjusting the amount of intake air passing through the turbo unit 10 is disposed between the upstream side connection portion of the bypass passage 20 to the intake passage 2 and the turbo unit 10. Further, an end of a connection pipe (negative pressure derivation path) 31 that guides the negative pressure generated in this portion to the negative pressure tank 30 is connected between the control valve 29 and the turbo unit 10. The opening degree of the adjusting valve 29 is adjusted by a motor 32, and the opening degree is detected by an opening degree sensor 33 provided therewith. The motor 32 and the opening degree sensor 33 are connected to the ECU 11. The negative pressure tank 30 stores negative pressure therein and has a pressure sensor (tank pressure detection means) 34 for detecting the internal pressure. The pressure sensor 34 is also connected to the ECU 11, and the pressure in the negative pressure tank 30 is monitored by the ECU 11.

  A check valve 35 for preventing the negative pressure stored in the negative pressure tank 30 from leaking to the intake passage 2 side is attached in the middle of the connection pipe 31 that guides the negative pressure to the negative pressure tank 30. The negative pressure tank 30 is connected to a brake booster 36 and various devices 37 that use negative pressure. An example of the various devices 37 includes a valve for changing the effective intake pipe length. When the negative pressure in the negative pressure tank 30 is used, the pressure in the negative pressure tank 30 gradually increases. Therefore, the motor 10b described above is set so that the pressure in the negative pressure tank 30 becomes less than a predetermined reference pressure. The bypass valve 22 and the adjustment valve 29 are controlled. This control will be described in detail later.

  A normal throttle valve 17 that adjusts the intake air amount is disposed downstream of the intercooler 16. The throttle valve 17 of the present embodiment is a so-called electronically controlled throttle valve, and the operation amount of the accelerator pedal 18 is detected by an accelerator positioning sensor 19, and the ECU 11 detects the throttle valve 17 based on this detection result and other information amounts. Determine the opening of. The throttle valve 17 is opened and closed by a throttle motor that is attached thereto. Further, a throttle positioning sensor 21 for detecting the opening degree is also provided along with the throttle valve 17.

  On the other hand, on the exhaust passage 8, an exhaust purification catalyst 39 for purifying exhaust gas is attached to the downstream side of the turbo unit 10. Further, a crank positioning sensor 25 for detecting the rotational position of the crankshaft is attached in the vicinity of the crankshaft of the engine 1. The rotation speed of the engine 1 can also be detected from the detection result of the crank positioning sensor 25. The ECU 11 is also connected with a water temperature sensor 26 and a knock sensor 27 that detect the temperature of the engine cooling water. Also, a cam positioning sensor 28 for detecting the opening / closing timing of the intake valve 7 (and the exhaust valve 9) is attached in the vicinity of the intake-side camshaft. Furthermore, an atmospheric pressure sensor 38 that detects atmospheric pressure is also connected to the ECU 11.

  The sensors described above are connected to the ECU 11 and send the detection results to the ECU 11. The ECU 11 is an electronic control unit that includes a CPU, a ROM, a RAM, and the like. Actuators other than the motor 10b and the motors 23 and 32 described above are also connected to the ECU 11, and these are controlled by signals from the ECU 11. In addition to this, the controller 12 and the battery 13 are also connected to the ECU 11 as described above.

  Next, control for generating a negative pressure in the intake passage 2 and storing the negative pressure in the negative pressure tank 30 will be described. First, regarding the generation of negative pressure, basically, negative pressure is generated on the upstream side of the turbo unit 10 by driving the motor 10b of the turbo unit 10 and supercharging it. By closing the bypass valve 22 and performing supercharging with the turbo unit 10, a negative pressure is formed on the upstream side of the turbo unit 10, and this negative pressure is stored in the negative pressure tank 30 via the connection pipe 31. At this time, by narrowing the opening of the control valve 29, the pressure in the section between the control valve 29 and the turbo unit 10 in the intake passage 2 can be further reduced, and negative pressure can be generated efficiently.

The upstream pressure of the turbo unit 10 on the intake passage 2 is P _I , the downstream pressure is P _O , the intake air amount detected by the air flow meter 14 is Ga, and the boundary where the surging occurs in the turbo unit 10 (surge) FIG. 2 shows the line) on the pressure ratio P _O / P _I -intake air amount Ga coordinate axis. Upstream pressure P _I can be detected by the atmospheric pressure sensor 38, the downstream pressure P _O can be detected by a pressure sensor 15. Here, at this time, the bypass valve 22 is closed so that the intake air does not flow backward. The bypass valve 22 may be configured such that a slight gap is formed between the bypass valve 22 and the inner wall of the intake pipe at a minimum opening degree in order to avoid sticking in the fully closed state. Further, when the negative pressure is generated, the opening of the bypass valve 22 may not be closed until it is fully closed, but only the opening degree thereof may be reduced.

A line indicated by X in FIG. 2 is a surge line. The region after the surge line exceeds the pressure side P _O / P _I from the small side to the large side is the region where surging occurs. Here, a desired negative pressure is generated by adjusting the driving amount of the motor 10b and the opening degree of the adjusting valve 29. At this time, it is necessary to avoid the surge of the turbo unit 10. For example, if the current situation is in the state of point a in FIG. 2, if the desired negative pressure (100% of the target) is to be obtained simply by reducing the opening of the control valve 29, the state is point. It is assumed that the transition to b can be predicted. Here, when the negative pressure is positively generated, the bypass valve 22 is set to a predetermined minimum opening [may be fully closed].

When the opening degree of the control valve 29 is reduced, the intake air amount Ga decreases and the pressure ratio P _O / P _I tends to increase. Therefore, the point b is located at the upper left with respect to the point a. In this case, since it crosses the surge line X, it can be predicted that surging will occur. In such a case, the motor 10b is driven in addition to about half of the desired negative pressure (50% of the target: corresponding to the point c in FIG. 2) by narrowing the opening of the adjustment valve 29. Thus, the remaining negative pressure is obtained (here, 80-50 from the point c to the point d in FIG. 2 = 30% of the target).

  When the motor 10b is driven, the intake air amount Ga increases due to the supercharging effect, and the downstream pressure of the turbo unit 10 increases. Therefore, the point d is located on the upper right side with respect to the point c. Thus, by reducing the opening degree of the adjustment valve 29 and promoting supercharging by driving the motor 10b, a desired negative pressure can be obtained while suppressing surging. In this example, it has been described that 80% of the target is achieved, but of course, there may be cases where the negative pressure of 100% of the target can be achieved.

  Another example will be described. If the current situation is in the state of point e in FIG. 2, it is possible to obtain a desired negative pressure (100% of the target) without causing surging by simply reducing the opening of the control valve 29. Suppose that it can be predicted. In this case, the state can be predicted to shift from point e to point f. Here again, the bypass valve 22 has a predetermined minimum opening. However, in this case, since the opening degree of the adjustment valve 29 is reduced, the intake air amount Ga supplied to the engine 1 is reduced, and there is a concern that the output of the engine 1 may be reduced. Therefore, by driving the motor 10b and performing supercharging, the intake air amount Ga is compensated and the output of the engine 1 is prevented from lowering. In this case, the state can be predicted to shift from point e to point g.

  Although the opening degree of the bypass valve 22 is reduced when the negative pressure is generated, by adjusting the opening degree of the bypass valve 22, the intake air can be controlled to flow downstream without going through the turbo unit 10 (one intake air). Part may go through the turbo unit 10). When the turbo unit 10 becomes an intake resistance and this is avoided, the opening degree of the bypass valve 22 is increased. For example, when regenerative power generation is performed by the motor 10b, the intake resistance in the turbo unit 10 increases. In such a case, by increasing the opening degree of the bypass valve 22, it is possible to secure the intake amount and secure the output of the engine 1.

Next, the negative pressure control described above will be described based on the flowchart of FIG. First, the pressure inside the negative pressure tank 30 is detected by the pressure sensor 34 (step 300). Next, it is determined whether or not supercharging is necessary, that is, whether supercharging is being performed or whether supercharging is to be started (step 305). If supercharging is not necessary, it is determined whether or not the pressure in the negative pressure tank 30 is equal to or higher than a predetermined reference pressure P _L for non-supercharging (step 310). The reference pressure P _L is set as an indication of whether or not the negative pressure in the negative pressure tank 30 is in sufficient level.

Step 310 is affirmative, when the negative pressure in the negative pressure tank 30 is the reference pressure P _L or more, it can be determined that the negative pressure in the negative pressure tank 30 is insufficient (the pressure is high) In consideration of generating sufficient negative pressure on the intake passage 2, negative pressure control is started (with emphasis) (step 315). At this time, supercharging is not required from the viewpoint of engine output, but it is also conceivable that negative pressure is generated by coordinating the drive control of the motor 10b in addition to the opening control of the adjustment valve 29. In such a case, the opening degree of the adjustment valve 29 is set to the minimum opening degree, and the driving amount of the motor 10b is adjusted according to the necessary negative pressure generation amount, thereby reducing the power consumption and minimizing the fuel consumption. Can be reduced.

The negative pressure control at this time is control in which the bypass valve 22 is set to the minimum opening, and the driving amount of the motor 10b and the opening (throttle amount) of the adjustment valve 29 are determined so as to generate a desired negative pressure. The driving amount of the motor 10b and the opening degree of the adjustment valve 29 are calculated by the amount of air required by the engine (calculated from the engine speed detected by the crank positioning sensor 25, the intake air amount detected by the air flow meter 14, etc.). And the output requested by the driver (calculated from the operation amount of the accelerator pedal 18 detected by the accelerator positioning sensor 19). On the other hand, is negative step 310, if the negative pressure in the negative pressure tank 30 is less than the reference pressure P _L is the negative pressure in the negative pressure tank 30 is not low, without the negative pressure control described above Then, the control of the flowchart of FIG.

Further, step 305 is affirmative, whether the supercharging in the case it is determined that the state starts from now supercharging, a predetermined reference pressure P _H for time pressure boost negative pressure tank 30 It is determined whether or not this is the case (step 320). When step 320 is affirmed, negative pressure control is performed in the subsequent steps. However, when step 320 is negative, negative pressure control is not performed, and the control of the flowchart of FIG. 3 ends. The reference pressure P _H also similar to the reference pressure P _H for when supercharging as described above, the negative pressure in the negative pressure tank 30 is set as indicating whether the sufficient level. However, P _H > P _L.

Negative pressure thus, changing the reference pressure in the boost required time and required time, the reference pressure P _H during the required in set higher to than the reference pressure P _L at the time required, when the supercharging is required The frequency of occurrence can be reduced. As a result, it is possible to further avoid a reduction in engine output due to the generation of negative pressure. When generating negative pressure, it may not be necessary to secure the intake air amount by promoting supercharging by the motor 10b and reduce the engine output. However, generating negative pressure leads to a decrease in engine output. There is also. Therefore, by setting the reference pressure in this way, a decrease in engine output can be further avoided.

If step 320 is affirmed, it is next determined whether surging occurs by generating a target negative pressure (step 325). Here, the target negative pressure is calculated based on the pressure in the negative pressure tank 30 detected by the pressure sensor 34. Then, in consideration of the supercharging pressure required for the turbo unit 10, it is determined whether or not surging occurs only by controlling the opening of the adjustment valve 29. Surging occurs a longitudinal pressure ratio _P O / _{P I} of the turbo unit 10 is increased. That is, it is determined whether or not the control from the point a to the point b in FIG. 2 is predicted.

  When surging is predicted and step 325 is affirmed, the opening degree of the control valve 29 and the driving amount of the motor 10b are determined so that the control from point a to point d in FIG. Negative pressure control in the vicinity of the line is executed (step 330). If it is predicted that no surging will occur and step 325 is negative, it is next determined whether or not the reduction in supercharging can be compensated (step 335). For example, as described above, even if the supercharging effect is reduced by reducing the opening of the adjustment valve 29 to generate the negative pressure, the intake air amount is reduced and the intake air amount is reduced by increasing the drive amount of the motor 10b. Sometimes the amount can be compensated. In this way, it is determined here whether or not the reduction in supercharging can be compensated.

  If it can be determined that the reduction in supercharging can be compensated and step 335 is affirmed, the control valve 29 is throttled and the drive amount of the motor 10b is increased (including stop → start of drive) (step 340). Thereby, a negative pressure can be generated while ensuring the engine output. On the other hand, when it is predicted that the decrease in supercharging cannot be compensated for by the negative pressure generation and Step 335 is negative, it is determined whether or not the negative pressure generation is prioritized over the supercharging (Step 345). When giving priority to negative pressure generation, negative pressure control is performed and the amount of injected fuel is reduced (step 350).

  Here, the fuel reduction is performed simultaneously with the negative pressure control. However, when the fuel reduction is not performed simultaneously, the intake air amount is reduced by reducing the opening of the adjustment valve 29 in order to generate the negative pressure. Control for reducing the amount of fuel is performed by feedback control (for example, air-fuel ratio feedback control) by decreasing the amount. However, the exhaust gas purification performance deteriorates due to the response delay that occurs during this control. Therefore, as described above, without waiting for feedback control, negative pressure control (decreasing the opening of the adjustment valve 29 and increasing the driving amount of the motor 10b: if the motor 10b is already fully opened, it may not be increased. ) And the amount of injected fuel is reduced in advance to suppress the deterioration of the exhaust purification performance. On the other hand, when supercharging is prioritized over generating negative pressure, negative pressure generation control is not performed and the supercharging is continued as it is (step 355).

  In the case of the present embodiment, the minimum opening degree of the adjustment valve 29 when generating the negative pressure is not fully closed, and a certain amount of the intake passage flows. This minimum opening is set as an opening that secures a flow path area capable of generating the required minimum negative pressure when the motor 10b is driven at the maximum drive amount. By doing in this way, even if the adjustment valve 29 is fixed at the minimum opening, it is possible to generate a negative pressure and secure the intake air amount.

The present invention is not limited to the embodiment described above. For example, in the above-described embodiment, the bypass valve 22 and the adjustment valve 29 adjust the flow rate according to their opening degrees. However, the flow rate may be adjusted by adjusting the open / close DUTY ratio. In this case, a value corresponding to the valve opening can be detected from the valve drive signal (DUTY ratio). In the embodiment described above, occurrence of surging is predicted (step 325). However, the pressure before and after the turbo unit 10 may be directly detected, and the occurrence of surging (or the state immediately before surging occurs) may be directly detected from the pressure ratio P _O / P _I.

It is a block diagram which shows the structure of the internal combustion engine (engine) which has one Embodiment of the control apparatus of this invention. It is explanatory drawing explaining the state transition by the surge boundary and negative pressure control shown on the coordinate axis of intake air amount-turbo unit front-back pressure ratio. It is a flowchart which shows negative pressure control.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine (internal combustion engine), 2 ... Intake passage, 3 ... Cylinder, 10 ... Turbo unit (supercharger), 10a ... Turbine / compressor, 10b ... Motor (electric motor), 11 ... ECU (control means), 12 ... Controller, 13 ... Battery, 14 ... Air flow meter, 17 ... Throttle valve, 18 ... Accelerator pedal, 19 ... Accelerator positioning sensor, 20 ... Bypass passage, 22 ... Bypass valve, 23 ... Motor, 24 ... Opening sensor, 25 ... Crank Positioning sensor, 29 ... control valve, 30 ... negative pressure tank, 31 ... connecting pipe (negative pressure derivation path), 32 ... motor, 33 ... opening sensor, 34 ... pressure sensor (tank pressure detecting means), 35 ... reverse Stop valve, 36 ... brake booster, 37 ... various devices, 38 ... atmospheric pressure sensor.

Claims (5)

A control device for an internal combustion engine for a vehicle provided with a supercharger that can be driven by an electric motor on an intake passage,
A bypass passage for bypassing the upstream side and the downstream side of the supercharger of the intake passage;
A bypass valve disposed on the bypass path and configured to adjust an intake air amount passing through the bypass path;
Control means for controlling the electric motor and the bypass valve; and
A control apparatus for an internal combustion engine for a vehicle, comprising a negative pressure lead-out path connected to an upstream side of the supercharger in the intake passage or an upstream side of the bypass valve in the bypass path. . A negative pressure tank connected to the negative pressure derivation path; and a tank pressure detecting means for detecting a pressure in the negative pressure tank,
The control means increases the drive amount of the motor and decreases the opening degree of the bypass valve when the pressure in the tank detected by the tank pressure detection means exceeds a predetermined reference pressure. The control apparatus for an internal combustion engine for a vehicle according to claim 1, wherein: Further comprising supercharging necessity judging means for judging whether supercharging to the internal combustion engine is necessary,
The reference pressure is set lower when the supercharging necessity determination means determines that supercharging is unnecessary than when it is determined that supercharging is required. A control device for an internal combustion engine for a vehicle according to claim 1. An adjustment valve for adjusting the amount of intake air that passes through the intake passage is further provided on the intake passage between the upstream connection portion of the bypass passage to the intake passage and the supercharger;
The vehicular internal combustion engine according to any one of claims 1 to 3, wherein the negative pressure lead-out path is connected to the intake passage between the supercharger and the control valve. Control device. A negative pressure tank connected to the negative pressure derivation path; and a tank pressure detecting means for detecting a pressure in the negative pressure tank,
When the pressure in the tank detected by the tank pressure detection means is equal to or higher than a predetermined reference pressure, the control means increases the drive amount of the electric motor and throttles the opening of the adjustment valve. The control apparatus for an internal combustion engine for a vehicle according to claim 4.

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