JP2008115792A - Supercharging control device - Google Patents

Abstract

A supercharging control device capable of more effectively utilizing the capacity of a supercharger is provided.
A supercharging control device according to the present invention includes a supercharger 20 disposed on an intake passage 5 of an engine 1 and an air flow meter 27 that detects a change rate indicating an operating state of an operating state value of the engine 1. The ECU 16 that sets the target maximum supercharging pressure of the supercharger 20 based on the change rate of the operating state value detected by the air flow meter 27, and the supercharger 20 based on the set target maximum supercharging pressure. And a controller 21 to be controlled. Here, the target maximum boost pressure set by the ECU 16 is larger than the boost pressure upper limit set based on the operating state. For this reason, the capability of the supercharger 20 can be utilized more effectively.
[Selection] Figure 1

Description

  The present invention relates to a supercharging control device for a supercharger disposed on an intake passage of an internal combustion engine.

  2. Description of the Related Art Conventionally, it has been proposed to arrange a compressor on an internal combustion engine, that is, an intake passage of the engine, and perform supercharging by the compressor to obtain high output or low fuel consumption. A typical turbocharger is such a turbocharger. A control device for a supercharger with an electric motor described in Patent Document 1 includes a supercharger disposed on an intake passage of an internal combustion engine and driven by the electric motor, and a supercharger that controls the electric motor to control the supercharging pressure. A pressure control means, an operating condition detecting means for detecting the operating condition of the internal combustion engine based on the intake air amount by the supercharger, and a supercharging pressure upper limit that can be supercharged by the supercharger based on the detected operating condition. An upper limit setting means for setting, and the supercharging pressure control means prohibits driving of the supercharger exceeding the upper limit of the supercharging pressure set by the upper limit setting means.

Thereby, the supercharging upper limit which arises by various factors can be set based on the driving | running state, and supercharging can be performed using the capability of a supercharger effectively in the range which does not exceed this upper limit. Here, various factors include the physical limit determined by the capacity of the turbocharger, the endurance limit of the turbocharger, or the output characteristics of the motor. It can be used as effectively as possible.
JP 2004-308485 A

  According to the above-described control device for the supercharger with electric motor, the operating state of the internal combustion engine is detected based on the intake air amount by the supercharger, and the supercharging pressure that can be supercharged by the supercharger based on this operating state An upper limit is set, and supercharging is performed by effectively using the capacity of the turbocharger within a range not exceeding this upper limit. However, no consideration is given to more effective use of the turbocharger capacity.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a supercharging control device that can more effectively use the capacity of the supercharger.

  The inventor has intensively studied to solve the above-described problems, and has set the target maximum supercharging set based on the change rate of the operating state value indicating the operating state that is larger than the upper limit of the supercharging pressure set based on the operating state. It has been found that surging can be prevented as long as the pressure is not exceeded, so that the capacity of the turbocharger can be used more effectively. The present invention has been made based on this finding.

  A supercharging control device according to the present invention includes a supercharger disposed on an intake passage of an internal combustion engine, operating state detection means for detecting an operating state value indicating an operating state of the internal combustion engine, and an operating state detection Target supercharging pressure setting means for setting the target maximum supercharging pressure of the supercharger based on the rate of change of the operating state value detected by the means, and control means for controlling the supercharger based on the target maximum supercharging pressure And.

  According to the supercharging control device according to the present invention, the target maximum supercharging pressure of the supercharger is set by the target supercharging pressure setting unit based on the rate of change of the operating state value detected by the operating state detecting unit, Control of the supercharger based on the target maximum supercharging pressure is performed by the control means. Here, the target maximum supercharging pressure of the supercharger is set based on the change rate of the operating state value, and the supercharger is controlled based on this target maximum supercharging pressure. For this reason, the capability of a supercharger can be utilized more effectively.

  A supercharging control device according to the present invention includes a supercharger disposed on an intake passage of an internal combustion engine, an operating state detecting unit that detects an operating state value indicating an operating state of the internal combustion engine, and an operating state detecting unit. Target supercharging pressure setting means for setting the target maximum supercharging pressure of the supercharger based on the detected change rate of the operating state value, control means for controlling the supercharger based on the target maximum supercharging pressure, And a supercharger comprising: a compressor for supercharging intake air; a turbine connected to the compressor and driven by exhaust gas discharged from an internal combustion engine; and an adjusting means for adjusting an inlet pressure of the turbine. The control means controls the adjusting means based on the target maximum supercharging pressure.

  According to the supercharging control device according to the present invention, the target maximum supercharging pressure of the supercharger is set by the target supercharging pressure setting unit based on the rate of change of the operating state value detected by the operating state detecting unit, Control of the supercharger based on the target maximum supercharging pressure is performed by the control means. Here, the target maximum supercharging pressure of the supercharger is set based on the change rate of the operating state value, and the supercharger is controlled based on this target maximum supercharging pressure. For this reason, the capability of a supercharger can be utilized more effectively. Further, the control unit controls the adjusting unit based on the target maximum supercharging pressure. Thereby, it is possible to control the adjusting means so that the supercharging pressure approaches the target maximum supercharging pressure.

  A supercharging control device according to the present invention includes a supercharger disposed on an intake passage of an internal combustion engine, an operating state detecting unit that detects an operating state value indicating an operating state of the internal combustion engine, and an operating state detecting unit. Target supercharging pressure setting means for setting the target maximum supercharging pressure of the supercharger based on the detected change rate of the operating state value, control means for controlling the supercharger based on the target maximum supercharging pressure, The control means adjusts the fuel injection amount to the internal combustion engine based on the target maximum supercharging pressure.

  According to the supercharging control device according to the present invention, the target maximum supercharging pressure of the supercharger is set by the target supercharging pressure setting unit based on the rate of change of the operating state value detected by the operating state detecting unit, Control of the supercharger based on the target maximum supercharging pressure is performed by the control means. Here, the target maximum supercharging pressure of the supercharger is set based on the change rate of the operating state value, and the supercharger is controlled based on this target maximum supercharging pressure. For this reason, the capability of a supercharger can be utilized more effectively. Further, the fuel injection amount to the internal combustion engine is adjusted by the control means based on the target maximum supercharging pressure. As a result, the fuel injection amount suitable for the intake air amount corresponding to the target maximum supercharging pressure can be adjusted.

  A supercharging control device according to the present invention includes a supercharger disposed on an intake passage of an internal combustion engine, an operating state detecting unit that detects an operating state value indicating an operating state of the internal combustion engine, and an operating state detecting unit. Target supercharging pressure setting means for setting the target maximum supercharging pressure of the supercharger based on the detected change rate of the operating state value, control means for controlling the supercharger based on the target maximum supercharging pressure, A bypass passage that bypasses the supercharger and allows intake air to flow downstream of the supercharger; and an intake air amount adjustment means that adjusts an intake air amount flowing into the bypass passage; and the control means is a target supercharging pressure setting means The intake air amount adjusting means is controlled on the basis of the target maximum supercharging pressure set by.

  According to the supercharging control device according to the present invention, the target maximum supercharging pressure of the supercharger is set by the target supercharging pressure setting unit based on the rate of change of the operating state value detected by the operating state detecting unit, Control of the supercharger based on the target maximum supercharging pressure is performed by the control means. Here, the target maximum supercharging pressure of the supercharger is set based on the change rate of the operating state value, and the supercharger is controlled based on this target maximum supercharging pressure. For this reason, the capability of a supercharger can be utilized more effectively. Further, the control of the intake air amount adjusting means based on the target maximum supercharging pressure is performed by the control means. Here, since the target maximum supercharging pressure of the supercharger is set based on the rate of change of the operating state value, the ability of the supercharger can be used more effectively by controlling the intake air amount adjusting means. it can.

  The supercharging control device according to the present invention preferably further includes an electric motor that drives the supercharger, and the control means controls the electric motor based on the target maximum supercharging pressure.

  In this way, the control of the electric motor based on the target maximum supercharging pressure is performed by the control means. Thereby, the electric motor can be controlled so that the supercharging pressure approaches the target maximum supercharging pressure.

  Further, the supercharging control device according to the present invention further comprises a charging state detecting means for detecting a charging state of a battery that supplies electric power to the electric motor, and the target supercharging pressure setting means is a battery detected by the charging state detecting means. It is preferable to set the target maximum supercharging pressure based on the state of charge.

  In this way, the target maximum boost pressure is set by the target boost pressure setting means based on the state of charge of the battery detected by the charge state detection means. Accordingly, the capacity of the supercharger can be used more effectively in consideration of the state of charge of the battery that supplies power to the electric motor.

  In the supercharging control device according to the present invention, the target supercharging pressure setting means preferably increases the target maximum supercharging pressure as the change rate of the operating state value detected by the operating state detecting means increases.

  In this way, the capacity of the supercharger is used more effectively until the target maximum supercharging pressure set by the target supercharging pressure setting means becomes larger as the change rate of the operating state value increases. be able to.

  In the supercharging control device according to the present invention, the operating state value of the internal combustion engine is preferably the amount of intake air taken into the internal combustion engine.

  In this way, it is possible to detect the intake air amount as the operating state value and set the target maximum supercharging pressure based on the rate of change of the intake air amount.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to utilize the capability of a supercharger more effectively.

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

  Note that the term “supercharging pressure” is sometimes used as a term indicating a differential pressure with respect to atmospheric pressure. On the other hand, the term “supercharging pressure” may be used as a term indicating absolute pressure in the intake pipe. In the following, when it is necessary to divide and explain the two, the explanation will be made so that the point is clear. For example, when supercharging pressure control is performed based on the output of a pressure sensor that detects the pressure in the intake pipe, if this pressure sensor is a sensor that detects a differential pressure with respect to atmospheric pressure, the supercharging pressure control is “as a difference with respect to atmospheric pressure”. It is easy to control based on the “supercharging pressure”, and if the pressure sensor detects the absolute pressure, the supercharging pressure control is controlled based on the “intake pressure as the absolute pressure”. Is easy.

  The engine 1 described in the present embodiment is a multi-cylinder engine, but only one cylinder is shown in FIG. 1 as a sectional view. The engine 1 is a type of engine in which fuel is injected into a cylinder 3 by an injector 2. The engine 1 is a so-called lean burn engine and can also perform stratified combustion. A supercharger 20 as a first supercharger driven by a motor 20a, which will be described later, and a turbo unit 11 as a second supercharger supercharge more intake air to increase output. It is possible to realize not only low fuel consumption.

  The engine 1 can perform stratified combustion by injecting fuel into a recess formed in the upper surface of the piston 4 during the compression stroke, and can also perform normal homogeneous combustion by intake stroke injection. An intake valve 8 opens and closes the inside of the cylinder 3 and the intake passage 5. The exhaust gas after combustion is exhausted to the exhaust passage 6. An exhaust valve 9 opens and closes the inside of the cylinder 3 and the exhaust passage 6. On the intake passage 5, an air cleaner 10, an air flow meter 27, a supercharger 20, a turbo unit 11, an intercooler 12, a throttle valve 13, and the like are arranged from the upstream side.

  The air cleaner 10 is a filter that removes dust and dirt in the intake air. The air flow meter 27 of this embodiment is of a hot wire type and detects the amount of intake air as a mass flow rate. The supercharger 20 is electrically driven by a built-in electric motor, that is, a motor 20a. A compressor wheel is directly connected to the output shaft of the motor 20a. The motor 20 a of the supercharger 20 is connected to the battery 22 via the controller 21. The controller 21 controls the drive power of the motor 20a by controlling the power supplied to the motor 20a. The controller 21 can detect the rotation speed of the motor 20a, that is, the rotation speed of the compressor wheel.

  A bypass path 24 is provided so as to bypass the upstream side and the downstream side of the supercharger 20. For this reason, the bypass path 24 can allow intake air to flow downstream of the supercharger 20. On the bypass path 24, a valve 25 as an intake air amount adjusting means capable of adjusting the intake air amount passing through the bypass path 24 is disposed. The valve 25 is electrically driven by the ECU 16, and the air flow rate through the bypass passage 24 is arbitrarily adjusted based on a target maximum supercharging pressure described later. When the supercharger 20 is not operating, the supercharger 20 acts as an intake resistance, so that the bypass 25 is opened by the valve 25 to avoid the supercharger 20 becoming an intake resistance. To do.

  The turbo unit 11 is disposed between the intake passage 5 and the exhaust passage 6 and performs supercharging. That is, in the engine 1 of the present embodiment, supercharging can be performed by the supercharger 20 as the first supercharger and the turbo unit 11 as the second supercharger arranged in series. The turbo unit 11 includes a compressor 11b that supercharges intake air, an exhaust turbine 11c that is connected to the compressor 11b by a rotation shaft, and a variable nozzle mechanism 11a that is provided in the exhaust turbine 11c. The exhaust turbine 11 c is operated by exhaust gas that passes from the engine 1 through the exhaust passage 6. The variable nozzle mechanism 11a is a mechanism as an adjusting means that can arbitrarily variably control the opening of the variable nozzle to adjust the inlet pressure of the exhaust turbine 11c. The opening degree variably controlled by the variable nozzle mechanism 11a is controlled by an ECU 16 described later based on a target maximum supercharging pressure described later.

  A supercharging pressure sensor 29 is disposed on the intake passage 5 between the bypass passage 24 and the turbo unit 11. The supercharging pressure sensor 29 detects the supercharging pressure when supercharging is performed by the supercharger 20. An air-cooled intercooler 12 is disposed on the downstream side of the turbo unit 11. The air-cooled intercooler 12 has a temperature of intake air whose temperature has increased due to pressure increase due to supercharging of the turbocharger 20 and the turbo unit 11. Lower. The temperature of the intake air is lowered by the intercooler 12 to improve the filling efficiency.

  A throttle valve 13 that adjusts the amount of intake air is disposed downstream of the intercooler 12. The throttle valve 13 of the present embodiment is a so-called electronically controlled throttle valve, and an operation amount of the accelerator pedal 14 is detected by an accelerator positioning sensor 15, and the ECU 16 detects the throttle valve 13 based on this detection result and other information amounts. Is determined. The throttle valve 13 is opened and closed by a throttle motor 17 that is provided in association therewith. Further, a throttle positioning sensor 18 that detects the opening degree of the throttle valve 13 is also provided.

  On the downstream side of the throttle valve 13, a pressure sensor 19 that detects a supercharging pressure or an intake pressure, which is a pressure in the intake passage 5, is also provided. These sensors 15, 18, 19, 27, and 29 are connected to the ECU 16 and send the detection results to the ECU 16. The ECU 16 is an electronic control unit that includes a CPU, a ROM, a RAM, and the like. The ECU 16 is connected to the injector 2, the spark plug 7, the valve 25, the air flow meter 27, the controller 21, the battery 22, and the like. These are controlled by signals from the ECU 16 or monitored by the ECU 16. -Detected. For example, in the case of the battery 22, the remaining amount of electric power and the state of charge are detected by the ECU 16. That is, in the present embodiment, the ECU 16 also functions as a charging state detection unit. For example, in the case of the injector 2, the fuel injection amount of fuel injected into the engine 1 is variably controlled by the ECU 16. That is, in the present embodiment, the ECU 16 also functions as an injection amount varying means.

  The motor 20 a of the supercharger 20 described above is also connected to the ECU 16 via the controller 21 and is controlled by the ECU 16 and the controller 21. The ECU 16 and the controller 21 control the driving of the supercharger 20 by controlling the motor 20a based on the target maximum supercharging pressure, and control the supercharging pressure of the supercharged air supercharged by the supercharger 20. To do. The ECU 16 and the controller 21 suppress the excess of the target maximum supercharging pressure, which is the maximum value of the target supercharging pressure, by such control. After such control is performed in a state where the target maximum supercharging pressure is exceeded, even if the target maximum supercharging pressure is still exceeded, the target maximum supercharging pressure is reduced. The degree of excess is smaller. The suppression control for exceeding the target maximum supercharging pressure may be control for suppressing the target maximum supercharging pressure from being excessively prohibited. For this reason, ECU16 and the controller 21 are functioning as a control means here.

  In the present embodiment, the supercharging pressure control is performed using the change rate of the intake air amount as the change rate of the operation state value obtained by quantifying the operation state of the engine 1. Since the change rate of the intake air amount is detected by the air flow meter 27, the air flow meter 27 functions as an operation state detection means here. Further, as will be described in detail later, a target maximum supercharging pressure at which supercharging is possible is set by the ECU 16 based on the detected change rate of the intake air amount, the state of charge of the battery 22, and the like. That is, in the present embodiment, the ECU 16 also functions as a target supercharging pressure setting unit.

  On the other hand, an exhaust purification catalyst 23 for purifying exhaust gas is attached on the exhaust passage 6 downstream of the turbo unit 11. A crank positioning sensor 26 that detects the rotational position of the crankshaft is attached in the vicinity of the crankshaft of the engine 1. The crank positioning sensor 26 can also detect the engine speed from the position of the crank position.

  In the present embodiment, the supercharging pressure by the supercharger 20 is detected by the supercharging pressure sensor 29, and the supercharger 20 is controlled using this value. However, the pressure in the intake pipe, that is, the intake manifold supercharging pressure, is acquired by the pressure sensor 19 on the intake passage 5, and based on the intake manifold supercharging pressure, the rotational speed of the turbo unit 11, and the air flow rate detected by the air flow meter 27. The supercharging pressure by the supercharger 20, that is, the supercharging pressure equivalent value detected by the supercharging pressure sensor 29 can be acquired. In such a case, the relationship among the intake manifold supercharging pressure, the turbo rotation speed, and the air flow rate may be mapped in advance, and this map may be referred to. In this way, it is possible to control based on the supercharging pressure detected by the pressure sensor 19.

  The supercharger 20 described above has an upper limit on the supercharging pressure that can be supercharged. There are multiple causes for these upper limits. The reasons for this are as follows. These are a physical limit due to the capacity of the supercharger 20 itself, a durability limit of the supercharger 20, a limit due to the output characteristics of the motor 20a that drives the supercharger 20, and the like. In the present embodiment, in consideration of the above-described causes, the ECU 16 determines, based on the change rate of the intake air amount detected by the air flow meter 27, as the change rate of the operation state value obtained by quantifying the operation state of the engine 1. The target maximum supercharging pressure is set, and the motor 20a is driven together with the controller 21 so that the supercharging pressure does not exceed the target maximum value or the excess is suppressed even if the target maximum value is exceeded. Control.

  That is, when the supercharging pressure exceeds the above-described target maximum supercharging pressure, the ECU 16 and the controller 21 perform control to suppress driving of the motor 20a including prohibition of driving of the motor 20a. More specifically, the ECU 16 and the controller 21 perform control to reduce and suppress the drive of the motor 20a by a predetermined ratio such as several percent to several tens of percent from the normal time. By suppressing the driving of the supercharger 20 in this way, the excess amount is reduced without exceeding the target maximum supercharging pressure or even when the target maximum supercharging pressure is exceeded. Can be used as much as possible. By making the best use of the capacity of the supercharger 20, it is possible to increase the output of the engine 1, and it is possible to improve the transient performance with respect to the output of the engine 1.

  The setting of the target maximum supercharging pressure described above will be described. The target maximum supercharging pressure described above is set large by the ECU 16 in accordance with the change rate of the intake air amount of the air sucked into the engine 1 as the change rate of the operating state value of the engine 1. That is, the target maximum supercharging pressure is set so that the target maximum supercharging pressure increases as the change rate of the intake air amount increases. The target maximum supercharging pressure can be set from the upper limit indicated by line A in FIG. 2 to the upper limit indicated by line B or line C. Thus, the lines A to C change according to the change rate of the intake air amount of air. In the graph of FIG. 2, the horizontal axis represents the engine speed and the vertical axis represents the supercharging pressure. It can be considered that the supercharging pressure is substantially proportional to the rotation speed of the compressor wheel of the supercharger 20, that is, the rotation speed of the motor 20a.

  Line A in FIG. 2 is a boundary line that causes a compressor surge or surging when the turbocharger 20 is in a steady state. That is, the line A is a so-called surge line in the map indicated by the supercharging pressure and the engine speed. In FIG. 2, the hatched side on the upper left side of line A is the surge region. The supercharging pressure indicated by the line A is set as a target maximum supercharging pressure reference value Pimtrgsrg.

  On the other hand, each of the line B and the line C in FIG. 2 is a target maximum supercharging pressure set in accordance with the magnitude of the change rate of the intake air amount. For example, the target maximum supercharging pressure when the change rate ΔGa of the intake air amount in the past 1 second is 0% is indicated by the line A, while the target maximum when the change rate ΔGa is 10%. The supercharging pressure is indicated by line B, and the target maximum supercharging pressure when the change rate ΔGa is 20% is indicated by line C. The supercharging pressure indicated by the line C is the maximum value that can be set as the target maximum supercharging pressure that can be set, and this supercharging pressure is set as the target maximum supercharging pressure upper limit value Pimtrgmaxm. The line is set by the ECU 16 when the motor 20a that drives the supercharger 20 is driven.

Here, the target maximum supercharging pressure Pimtrgmax set by the ECU 16 based on the magnitude of the change rate ΔGa of the intake air amount in the past one second is given by the following relational expression (1). That is, the target maximum supercharging pressure Pimtrgmax is a multiplication value obtained by multiplying the subtraction value obtained by subtracting the above-described target maximum supercharging pressure reference value Pimtrgsrg from the above-described target maximum supercharging pressure upper limit value Pimtrgmaxm by the coefficient k. And the above-mentioned target maximum supercharging pressure reference value Pimtrgsrg.

  The coefficient k in the relational expression (1) is determined based on the magnitude of the change rate ΔSe of the operating state value of the engine 1 according to the relational table shown in FIG. The relationship table of FIG. 3 shows the relationship between the change rate ΔSe of the operating state value and the coefficient k in the relational expression (1). Here, it is assumed that the change rate ΔGa of the intake air amount is used as the change rate ΔSe of the operating state value of the engine 1. For example, when the change rate ΔGa of the intake air amount is 10%, the coefficient k in the relational expression (1) is 0.5. Here, a region not shown in the relationship table, for example, a region where the change rate ΔSe of the operating state value is greater than 5 percent and less than 10 percent may be obtained by interpolation using a calculation method such as interpolation calculation.

  The variable nozzle mechanism 11a may arbitrarily variably control the opening degree Vnmax of the variable nozzle based on the target maximum supercharging pressure Pimtrgmax set by the above-described relationship. More specifically, as the target maximum supercharging pressure Pimtrgmax increases, the opening degree Vnmax of the variable nozzle is controlled to close, and as the target maximum supercharging pressure Pimtrgmax decreases, the opening degree Vnmax of the variable nozzle is controlled to open. May be.

  Further, the ECU 16 may arbitrarily variably control the fuel injection amount Qfullj of the fuel to be injected into the engine 1 based on the target maximum supercharging pressure Pimtrgmax set by the above relationship. More specifically, the fuel injection amount Qfullj is controlled to increase as the target maximum supercharging pressure Pimtrmax increases, and the fuel injection amount Qfullj may be controlled to decrease as the target maximum supercharging pressure Pimtrmax decreases. Good.

  Note that the motor output of the motor 20a may change due to a change in SOC (State Of Charge, that is, a charging state) including a charging state of a battery that supplies power to the motor 20a. Thus, since the motor output can change due to a change in SOC or the like, the reachable supercharging pressure can change. Therefore, the ECU 16 may set the target maximum supercharging pressure upper limit value Pimtrgmaxm based on the state of charge of the battery. More specifically, the ECU 16 may set a target maximum supercharging pressure upper limit value Pimtrgmaxm that is proportional to the state of charge of the battery.

  Here, it is possible to prevent surging from occurring unless the target maximum supercharging pressure Pimtrgmax set based on the rate of change of the operating state value, which is larger than the upper limit of the supercharging pressure set based on the operating state, is exceeded. I understood.

  According to the supercharging control device of the present embodiment, the target maximum supercharging pressure Pimtrmax of the supercharger 20 is set by the ECU 16 based on the change rate ΔGa of the intake air amount as the operating state value detected by the air flow meter 27. Is done. Then, the ECU 16 and the controller 21 perform control of the supercharger 20 based on the target maximum supercharging pressure Pimtrgmax. Here, since the target maximum supercharging pressure Pimtrgmax of the supercharger 20 is set based on the change rate ΔSe of the operating state value, the target maximum supercharging pressure Pimtrgmax is set based on the operating state. Greater than the upper limit. For this reason, the capability of the supercharger 20 can be utilized more effectively.

  In addition, the ECU 16 and the controller 21 perform control for prohibiting and suppressing exceeding the target maximum supercharging pressure Pimtrgmax set by the ECU 16. Thereby, since the target maximum supercharging pressure Pimtrgmax is not exceeded, the occurrence of surging can be prevented more reliably.

  Further, the ECU 16 and the controller 21 perform control of the motor 20a based on the target maximum supercharging pressure Pimtrgmax. Thereby, the motor 20a can be controlled so that the supercharging pressure approaches the target maximum supercharging pressure Pimtrgmax.

  Further, the target maximum supercharging pressure Pimtrgmax is set by the ECU 16 based on the SOC (State Of Charge, that is, the state of charge) of the battery detected by the ECU 16. Thus, the capacity of the supercharger 20 can be used more effectively after setting an appropriate target maximum supercharging pressure Pimtrgmax that also takes into account the state of charge of the battery that can change the supercharging pressure.

  Further, the ECU 16 performs control of the variable nozzle mechanism 11a based on the target maximum supercharging pressure Pimtrgmax set by the ECU 16. Thereby, the variable nozzle mechanism 11a can be controlled so that the supercharging pressure approaches the target maximum supercharging pressure Pimtrgmax.

  Further, the fuel injection amount to the engine 1 is adjusted by the ECU 16 and the controller 21 based on the target maximum supercharging pressure Pimtrgmax set by the ECU 16. As a result, the fuel injection amount suitable for the intake air amount corresponding to the target maximum supercharging pressure Pimtrgmax can be adjusted.

  Further, the ECU 16 is set so that the target maximum supercharging pressure Pimtrgmax increases as the change rate ΔSe of the operating state value increases, and surging can be prevented as long as the target maximum supercharging pressure Pimtrgmax is not exceeded. For this reason, the larger the change rate ΔSe of the operating state value, the more effectively the capacity of the supercharger 20 can be used while preventing the occurrence of surging.

  Further, it is possible to detect the intake air amount as the operating state value and set the target maximum supercharging pressure Pimtrgmax based on the change rate ΔGa of the intake air amount.

  Further, the ECU 16 controls the valve 25 based on the target maximum supercharging pressure Pimtrgmax set by the ECU 16. Here, since the target maximum supercharging pressure Pimtrgmax of the supercharger 20 is set based on the change rate ΔSe of the operating state value, more effective use of the capacity of the supercharger 20 by controlling the valve 25 is achieved. Is possible.

  In addition, this invention is not limited to embodiment mentioned above. For example, in the above-described embodiment, the present invention is applied to the engine 1 in which the supercharger 20 with the motor 20 a is provided separately from the turbo unit 11. However, it is also possible to apply the present invention in order to control the electric motor by incorporating the electric motor in the turbo unit 11 without integrating the supercharger 20 as described above. In this case, a bypass pipe is provided so as to bypass the upstream side and the downstream side of the compressor 11b of the turbo unit 11 in which the electric motor is built. The bypass pipe is provided with a valve as an intake air amount adjusting means capable of adjusting the amount of intake air passing through the bypass pipe. This valve is electrically driven by the ECU 16, and the air flow rate through this bypass pipe is arbitrarily adjusted based on the target maximum supercharging pressure Pimtrgmax.

  In the above-described embodiment, only the change rate ΔGa of the intake air amount is used as the change rate ΔSe of the operation state value. However, the information amount other than the change rate ΔGa of the intake air amount is used as the change rate ΔSe of the operation state value. You may do it. Further, instead of using only a single information amount, a plurality of information amounts may be used in combination. The amount of information other than the change rate ΔGa of the intake air amount includes the change rate ΔNe of the engine speed that can be detected by the crank positioning sensor 26 and the fuel injection amount when the injection command is sent from the ECU 16 to the injector 2. Examples include a change rate ΔQ, a supercharging pressure change rate ΔP, and an accelerator opening change rate ΔA.

  In the embodiment described above, the variable nozzle mechanism 11a is provided in the exhaust turbine 11c. However, the bypass pipe bypassing the upstream and downstream of the variable nozzle mechanism 11a without the variable nozzle mechanism 11a, and the bypass pipe A waste gate valve that is disposed in the ECU and connected to the ECU 16 may be provided. In this case, this waste gate valve is a valve as an adjusting means capable of adjusting the inlet pressure of the exhaust turbine 11c by adjusting the opening of the bypass pipe. The opening degree of the waste gate valve is controlled by the ECU 16 based on the target maximum supercharging pressure Pimtrgmax. In addition, while providing the variable nozzle mechanism 11a, you may provide these bypass pipes and waste gate valves.

It is a block diagram which shows the structure of the engine which has one Embodiment of the control apparatus of this invention. It is a graph which shows the usable area | region of a supercharger based on the relationship between an engine speed and a supercharging pressure. It is the table | surface which showed the relationship between change rate (DELTA) Se of a driving | running state value, and the coefficient k in relational expression (1).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Injector, 3 ... Cylinder, 4 ... Piston, 5 ... Intake passage, 6 ... Exhaust passage, 7 ... Spark plug, 8 ... Intake valve, 9 ... Exhaust valve, 10 ... Air cleaner, 11 ... Turbo unit, DESCRIPTION OF SYMBOLS 11a ... Variable nozzle mechanism, 11b ... Compressor, 11c ... Exhaust turbine, 12 ... Intercooler, 13 ... Throttle valve, 14 ... Accelerator pedal, 15 ... Accelerator positioning sensor, 16 ... ECU, 17 ... Throttle motor, 18 ... Throttle positioning sensor , 19 ... Pressure sensor, 20 ... Supercharger, 20a ... Motor, 21 ... Controller, 22 ... Battery, 23 ... Exhaust purification catalyst, 24 ... Bypass path, 25 ... Valve, 26 ... Crank positioning sensor, 27 ... Air flow meter, 29: Supercharging pressure sensor.

Claims (8)

A supercharger disposed on an intake passage of the internal combustion engine;
An operating state detecting means for detecting an operating state value indicating the operating state of the internal combustion engine;
Target supercharging pressure setting means for setting a target maximum supercharging pressure of the supercharger based on a change rate of the operating state value detected by the operating state detection means;
Control means for controlling the supercharger based on the target maximum supercharging pressure;
A supercharging control device comprising: A supercharger disposed on an intake passage of the internal combustion engine;
An operating state detecting means for detecting an operating state value indicating the operating state of the internal combustion engine;
Target supercharging pressure setting means for setting a target maximum supercharging pressure of the supercharger based on a change rate of the operating state value detected by the operating state detection means;
Control means for controlling the supercharger based on the target maximum supercharging pressure,
The supercharger has a compressor for supercharging intake air, a turbine connected to the compressor and driven by exhaust gas discharged from the internal combustion engine, and an adjusting means for adjusting an inlet pressure of the turbine. And
The supercharging control device, wherein the control unit controls the adjusting unit based on the target maximum supercharging pressure. A supercharger disposed on an intake passage of the internal combustion engine;
An operating state detecting means for detecting an operating state value indicating the operating state of the internal combustion engine;
Target supercharging pressure setting means for setting a target maximum supercharging pressure of the supercharger based on a change rate of the operating state value detected by the operating state detection means;
Control means for controlling the supercharger based on the target maximum supercharging pressure,
The supercharging control device, wherein the control means adjusts a fuel injection amount to the internal combustion engine based on the target maximum supercharging pressure. A supercharger disposed on an intake passage of the internal combustion engine;
An operating state detecting means for detecting an operating state value indicating the operating state of the internal combustion engine;
Target supercharging pressure setting means for setting a target maximum supercharging pressure of the supercharger based on a change rate of the operating state value detected by the operating state detection means;
Control means for controlling the supercharger based on the target maximum supercharging pressure;
A bypass path for bypassing the supercharger and allowing intake air to flow downstream of the supercharger;
An intake air amount adjusting means for adjusting an intake air amount flowing into the bypass passage;
The supercharging control device, wherein the control means controls the intake air amount adjusting means based on a target maximum supercharging pressure set by the target supercharging pressure setting means. An electric motor for driving the supercharger;
The supercharging control device according to any one of claims 1 to 4, wherein the control unit controls the electric motor based on the target maximum supercharging pressure. Charging state detection means for detecting a charging state of a battery that supplies power to the electric motor;
The target boost pressure setting means sets the target maximum boost pressure based on the state of charge of the battery detected by the charge state detection means. The supercharging control device described in 1. The target boost pressure setting means increases the target boost pressure as the change rate of the operation state value detected by the operation state detection means increases. The supercharging control device according to item 1. The supercharging control device according to any one of claims 1 to 7, wherein the operating state value of the internal combustion engine is an intake air amount sucked into the internal combustion engine.

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