JP6497174B2 - Control device for an internal combustion engine with a supercharger - Google Patents

Description

  The present disclosure relates to a control device for an internal combustion engine with a supercharger, and more particularly to a control device for a supercharging pressure by a supercharger.

  In an internal combustion engine with a supercharger, Patent Literature 1 and Patent Literature 2 are known as techniques related to supercharging pressure control. In Patent Document 1, the pressure ratio (pressure ratio between the upstream side and the downstream side of the compressor) of the exhaust turbocharger is always maintained in the vicinity of the surge line without being affected by changes in atmospheric pressure. It is disclosed to obtain sufficient engine torque while preventing it. Therefore, Patent Document 1 discloses that the supercharger pressure is controlled so that the difference between the surge limit pressure ratio and the pressure ratio at the operating position becomes a preset margin.

  Further, Patent Document 2 calculates a target throttle upstream pressure that is a target value of the pressure upstream of the throttle valve based on the target filling rate efficiency and the engine rotation speed, and calculates the target intake air amount and the target throttle upstream pressure. A technique for calculating a target compressor driving force based on the above and controlling the waste gate valve so as to become the target compressor driving force is disclosed.

JP 2001-342840 A JP 2013-224596 A

  However, in Patent Document 1, as described above, in order to maintain the pressure ratio of the compressor in the vicinity of the surge line, the supercharging pressure is controlled with a surplus amount from the surge line. Therefore, it is an object to prevent the turbocharger from being damaged because the efficiency as a turbocharger is suddenly reduced and the function as a turbocharger cannot be obtained. For this reason, it is not the supercharging pressure control that takes into account the performance and strength problems of the transmission and the internal combustion engine such as the allowable torque of the transmission and the knocking limit of the internal combustion engine.

  In particular, when a throttle valve for adjusting the intake air amount is provided on the downstream side of the turbocharger, an intake pressure loss corresponding to the throttle valve opening control occurs. The downstream pressure of the throttle valve, that is, the intake manifold pressure is not equivalent, and when the control for suppressing surging only by the pressure ratio between the downstream pressure and the upstream pressure of the turbocharger as in Patent Document 1, Considering the allowable torque of the transmission and the knocking limit of the internal combustion engine, etc., the vehicle is operated even when there is no margin, and is limited even when there is a margin. There is a problem that causes deterioration.

  On the other hand, Patent Document 2 discloses a technique for calculating the throttle upstream pressure from the target throttle downstream pressure and adjusting the opening of the waste gate valve based on the ratio of the atmospheric pressure. In the operating area, damage due to compressor surge is not considered. Furthermore, it is not disclosed until maintenance of fuel efficiency and improvement of acceleration performance.

  Therefore, in view of the above-described technical problems, an object of at least one embodiment of the present invention is to consider the requirements of the transmission or the internal combustion engine such as the allowable torque of the transmission and the knocking limit of the internal combustion engine while suppressing the surging of the compressor. Then, it is providing the control apparatus of the internal combustion engine with a supercharger which can improve a fuel consumption performance and acceleration performance.

(1) A control apparatus for an internal combustion engine with a supercharger according to at least one embodiment of the present invention includes a compressor for a supercharger that is rotated by a turbine provided in an exhaust passage of the internal combustion engine and compresses intake air, and the compressor A throttle valve that is provided downstream of the intake passage and adjusts the amount of intake air supplied to the internal combustion engine, and calculates a first target intake pressure downstream of the throttle valve as a target from the load and rotation of the internal combustion engine a first target intake pressure calculating means, and a second target intake pressure calculating means for calculating a second target intake pressure upstream of the throttle valve based on the first target intake pressure, the first and a supercharger control means for calculating a control target value of the compressor based on the target pressure ratio is the ratio of the second target intake pressure or the second target intake pressure and the atmospheric pressure A control apparatus for supplying an internal combustion engine with,
The supercharger control means is a first upper limit value calculating means for calculating an upper limit value of the first target intake pressure based on a combustion state of the internal combustion engine or a limit point of a driving device connected to the internal combustion engine. And second upper limit value calculating means for calculating an upper limit value of the second target intake pressure or the target pressure ratio, which is calculated based on a surging line of the compressor, and both the first and second upper limits. Pressure control means for calculating a control target value of the compressor within a range not exceeding the value and controlling the rotation speed of the compressor, wherein the pressure control means includes the first target intake pressure and the first target intake pressure. The second target intake pressure or the target pressure ratio is calculated on the basis of a small value by comparing with the upper limit value of the first target intake pressure calculated by the upper limit value calculating means, and calculated by the comparison The second eye To output a smaller value by comparing the intake pressure or the target pressure ratio and the second target intake pressure or the target pressure ratio calculated by the second upper limit value calculating means as a control target value of the compressor Features.

According to the configuration of (1), the intake pressure or the intake pressure ratio of the control target value is set to the upper limit value based on the surging line of the compressor and the combustion engine state of the internal combustion engine or the limit point of the drive device connected to the internal combustion engine. Since the internal combustion engine can be operated within a range that does not exceed both upper limit values and the upper limit value based on it, surging of the compressor can be reliably suppressed. Furthermore, engine performance can be maximized while preventing damage to the compressor.
Further, according to the configuration of (1), the two upper limit values of the comparison with the first upper limit value on the downstream side of the throttle valve and the comparison with the second upper limit value on the upstream side of the throttle valve are Since the comparison is output as a control target value for the compressor, surging of the compressor can be reliably suppressed. Furthermore, engine performance can be maximized while preventing damage to the compressor.

(2) In some embodiments, the internal combustion engine, the example Bei the intake air amount acquisition means for measuring or estimating the amount of intake air sucked into the internal combustion engine, the second upper limit value calculating means calculates the suction An intake air amount passing through the compressor is calculated based on the intake air amount measured by the air amount acquisition means, and the second target intake pressure or the target pressure ratio is calculated based on the intake air amount and a surge line of the compressor . An upper limit value is calculated.

According to the configuration of (2) , the second target intake pressure or the upper limit value of the target pressure ratio is calculated based on the surge line, and further , intake air amount acquisition for measuring or estimating the intake air amount passing through the compressor is obtained. Means.
For this reason, for example, even if there is a case where the valve overlap is less than expected due to insufficient hydraulic pressure of the variable valve timing mechanism, and it is difficult for air to enter the cylinder of the internal combustion engine and it may increase by mistake than the target pressure ratio. In such a case, the amount of intake air is reduced by that amount, and the second upper limit value also becomes the upper limit value reduced accordingly, so that the compressor can be reliably prevented from being damaged.
On the other hand, in the range not exceeding the second upper limit value, the engine performance can be maximally utilized by using the first upper limit value.

(3) In some embodiments, the upper limit value of the first target intake pressure is determined by at least an allowable torque of a driving force transmission unit that is connected to the internal combustion engine and transmits the driving force of the internal combustion engine. And

According to the configuration (3) , it is possible to prevent the driving force transmission means from being damaged.

(4) In some embodiments, the upper limit value of the second target intake pressure or the target pressure ratio is a value set with a predetermined margin with respect to the surge line of the compressor. And

According to the configuration of (4) , since the upper limit value of the second target intake pressure or target pressure ratio is set including a predetermined margin with respect to the compressor surge line, surging can be reliably prevented. .

  According to at least one embodiment of the present invention, fuel consumption performance and acceleration performance can be improved in consideration of transmission or internal combustion engine requirements such as transmission allowable torque and internal combustion engine knock limit while suppressing compressor surging. A control device for an internal combustion engine with a supercharger can be obtained.

1 is an overall configuration diagram of a control device for an internal combustion engine with a supercharger according to an embodiment of the present invention. 1 is a configuration block diagram of an ECU (electronic control unit) according to an embodiment of the present invention. It is a flowchart of control target value calculation in one Embodiment of this invention. 1 is a configuration block diagram of an ECU (electronic control unit) according to an embodiment of the present invention. It is a flowchart of control target value calculation in one Embodiment of this invention. It is explanatory drawing which shows the specific example of a control map.

Several embodiments of the present invention will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in these embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Only.
For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of other constituent elements.

FIG. 1 shows an overall configuration diagram of a control device for an internal combustion engine with a supercharger according to an embodiment of the present invention. As shown in FIG. 1, the intake passage 3 of the internal combustion engine (engine) 1 is provided with an air cleaner 5 from the upstream side, a compressor 9 of the exhaust supercharger 7 on the downstream side, and an intercooler 11 on the downstream side. Further, on the downstream side, a surge tank 15 formed in the intake manifold 13 and an intake port injector 19 for injecting fuel into the intake port 17 are provided.
Then, the intake air introduced through the air cleaner 5 passes through the intake passage 3, is introduced into the compressor 9, is compressed, then cooled by the intercooler 11, and then introduced into the surge tank 15, where the intake pressure is reduced. After equalization, the fuel is supplied to each cylinder, and fuel is injected from the intake port injector 19 into the intake port 17 and introduced into the combustion chamber 21 of the engine 1 as an air-fuel mixture.

The engine 1 includes a cylinder head 23 and a cylinder block 25. A piston 29 is accommodated in the cylinder block 25 so as to be reciprocally movable. The piston 29, the cylinder, and the cylinder head 23 include a combustion chamber. 21 is formed.
An intake port 17 is formed in the cylinder head 23, and an intake valve 31 is provided in the intake port 17, and the combustion chamber 21 and the intake port 17 are communicated and blocked by the intake valve 31. .

On the other hand, an exhaust port 33 is formed in the cylinder head 23, and an exhaust passage 35 is connected to the exhaust port 33 via an exhaust manifold. Further, the exhaust port 33 is provided with an exhaust valve 36, and the exhaust valve 36 communicates and blocks the combustion chamber 21 and the exhaust port 33. The intake valve 31 and the exhaust valve 36 are provided with variable timing mechanisms.
The exhaust passage 35 is provided with a turbine 37 of the exhaust supercharger 7 that is coaxially coupled to the compressor 9. An exhaust purification catalyst 39 is provided on the downstream side of the turbine 37.

Further, a bypass passage 41 is formed so as to bypass the turbine 37, and a waste gate valve 43 that adjusts the amount of exhaust gas introduced into the bypass passage 41 is provided at a joint portion between the bypass passage 41 and the exhaust passage 35. . The opening degree of the waste gate valve 43 is adjusted by a waste gate valve actuator 45.
The cylinder head 23 is provided with an ignition plug 47 for each cylinder, and an ignition coil for outputting a high voltage is connected to the ignition plug 47.

  An air flow meter 49 is installed in the intake passage 3 between the air cleaner 5 and the compressor 9 so as to detect the intake air flow rate flowing into the exhaust supercharger 7. The intake passage 3 between the intercooler 11 and the surge tank 15 is provided with a throttle valve 51 for adjusting the intake amount into the combustion chamber 21, and the upstream side for detecting the intake pressure upstream of the throttle valve 51. A pressure sensor 53 is provided, and a downstream pressure sensor 55 for detecting the intake pressure downstream of the throttle valve is provided in the surge tank 15.

The ECU (electronic control unit) 57 includes an input / output device, a storage device (ROM, RAM, etc.), a central processing unit (CPU), a timer counter, and the like. The ECU 57 performs overall control of the engine 1.
On the input side of the ECU 57, the above-described air flow meter 49, upstream pressure sensor 53, various sensors of the downstream pressure sensor 55, engine load sensor (fuel injection amount sensor) 59, engine rotation sensor (crank angle sensor) 61 Detection information from various sensors such as the atmospheric pressure sensor 63 is input.

The output side of the ECU 57 is connected to various output devices such as the intake port injector 19 and the spark plug 47 described above. The various output devices output the fuel injection amount, fuel injection timing, ignition timing, and the like calculated by the ECU 57 based on detection information from the sensors.
An appropriate target air-fuel ratio is set based on detection information from various sensors, and an appropriate amount of fuel is injected from the intake port injector 19 at an appropriate timing so that the actual air-fuel ratio becomes the target air-fuel ratio. The amount of air introduced into the combustion chamber 21 is adjusted by the throttle valve 51, and spark ignition is performed at an appropriate timing by the spark plug 47.
Further, by outputting a control signal to the waste gate valve actuator 45, the opening degree of the waste gate valve 43 is adjusted, and the compression pressure is controlled by the exhaust supercharger 7.

  The ECU 57 also has a target Pb converter (first target intake pressure calculation means) 71 that calculates a target intake air pressure (first target intake pressure) downstream of the throttle valve 51 from the load and rotation of the engine 1. A conversion unit 82 (second target intake pressure calculation means) for calculating the upstream intake pressure (second target intake pressure) of the throttle valve 51 based on the output of the target Pb conversion unit 71, and the upstream intake pressure Alternatively, a supercharger control means 65 that calculates a control target value of the compressor 9 based on a pressure ratio that is a ratio between the upstream intake pressure and the atmospheric pressure is provided.

Next, the target Pb conversion unit 71, the conversion unit 82, and the supercharger control means 65 will be described with reference to FIG.
Reference sign Pb indicates the downstream intake pressure on the downstream side of the throttle valve 51 and corresponds to the intake manifold pressure in the surge tank (intake manifold = intake manifold) 15. Reference sign P1 represents atmospheric pressure, and reference sign P2 represents upstream intake pressure upstream of the throttle valve 51.

  The target Pb conversion unit 71 performs conversion from the target EC (indicating target air charging efficiency and preset in a map or the like as a target value based on the engine load and the rotational speed) to the downstream intake pressure Pb. At the time of this conversion, the conversion is performed in consideration of a volumetric efficiency correction coefficient corresponding to the engine speed.

The conversion unit 82 includes a target P2 conversion amount setting unit 73, an adder 80, and a divider 84, and converts the intake pressure Pb on the downstream side of the throttle valve 51 into the upstream intake pressure P2 on the upstream side of the throttle valve 51. Then, the pressure ratio with the atmospheric pressure is further calculated.
The target P2 conversion amount setting unit 73 performs conversion using a target P2 conversion amount setting map 74 in which the conversion amount is set based on the engine speed and the target EC, as shown in FIGS. A quantity is calculated.
By adding the target P2 conversion amount from the target P2 conversion amount setting unit 73 with the adder 80 to the target Pb value output from the minimum value selector 78, the target Pb value is converted into the target P2 value. Divide by atmospheric pressure to calculate the target pressure ratio.

  The supercharger control unit 65 includes a target Pb upper limit value setting unit (first upper limit value calculation unit) 69 that is a downstream upper limit value calculation unit, and a target pressure ratio upper limit value setting unit that is an upstream upper limit value calculation unit ( (Second upper limit calculating means) 75 and the range of the compressor 9 within a range that does not exceed the upper limits of both the downstream upper limit and the upstream upper limit (within a range that does not exceed both the first and second upper limits). And a comparison unit (pressure control means) 90 for calculating a control target value.

  The target Pb upper limit setting unit 69 calculates the target Pb upper limit using a target Pb upper limit setting map 77 as shown in FIG. The target Pb upper limit value is set based on the engine speed, and is calculated based on the engine speed.

In the target pressure ratio upper limit value setting unit 75, as shown in FIG. 6D, the relationship between the upper limit value of the pressure ratio (the pressure ratio between the upstream side and the downstream side of the compressor 9) and the volume flow rate of the intake air is set. The target pressure ratio upper limit value is calculated using the pressure ratio upper limit value map 76. The upper limit value line M1 of the pressure ratio upper limit value map 76 is set including a predetermined margin (for example, approximately 10% in volume flow rate) with respect to the surge line M2 of the compressor 9. In this way, the upper limit value is set so that surging can be reliably prevented.
When the intake air amount detected by the air flow meter 49 is not a volume flow rate but a mass flow rate, it is divided by the air density and converted into a volume flow rate.
Further, the intake air amount may be calculated and acquired based on the intake negative pressure or the like.

Further, as described above, the target pressure ratio upper limit setting unit 75 calculates the target upper limit pressure ratio based on the surge line M2 of the compressor 9, and the surge line M2 of the compressor 9 receives the intake air amount and the pressure passing through the compressor 9. It depends on the ratio. Further, the amount of intake air that passes through the compressor is detected by an air flow meter 49.
For this reason, for example, even if there is a case where the valve overlap is less than expected due to insufficient hydraulic pressure of the variable valve timing mechanism, and it is difficult for air to enter the cylinder of the engine 1 and it may increase by mistake than the target pressure ratio. In such a case, the intake air amount is reduced by that amount, and the target upper limit pressure ratio becomes the upper limit value correspondingly reduced. Therefore, the compressor 9 can be reliably prevented from being damaged.

The target Pb upper limit value output from the target Pb upper limit value setting unit 69 and the target Pb value output from the target Pb conversion unit 71 are input to the minimum value selector 78, and the smaller value is adopted and the target is selected. Output as Pb value.
The target Pb upper limit value setting unit 69, the target Pb converting unit 71, and the minimum value selector 78 calculate the first target intake pressure on the downstream side of the throttle valve 51, that is, the target Pb value. As described above, the conversion unit 82 including the target P2 conversion amount setting unit 73, the adder 80, and the divider 84 converts the target Pb value on the downstream side of the throttle valve 51 into the target on the upstream side of the throttle valve 51. It is converted into a P2 value, and a target pressure ratio (P2 / P1) is further calculated.

  The target P2 value of the output of the conversion unit 82 is divided by the atmospheric pressure P1 by the divider 84 and calculated as the target pressure ratio (P2 / P1), and is input to the maximum value selector 86 and the pressure ratio is “1”. Compared to the case, the value larger than 1 is adopted to calculate the upstream target value. Then, the upstream target value is input to the minimum value selector 88.

On the other hand, the target pressure ratio upper limit value output from the target pressure ratio upper limit value setting unit 75 is input to the minimum value selector 88 as an upstream upper limit value. Then, the smaller one of the upstream target value and the upstream upper limit value is adopted, and the target pressure ratio (P2 / P1) is output as the control target value.
The minimum value selector 88 compares the target pressure ratio, which is the upstream target value, with the target pressure ratio upper limit value, which is the upstream upper limit value, and adopts the smaller value to output the control target value. It is like that.
The conversion unit 82 converts the upstream intake pressure P2 upstream of the throttle valve 51 to calculate the target pressure ratio, and the comparison unit 90 compares the target pressure ratio with the upper limit value. Since it becomes the same as the side, it is easy to compare and the comparison accuracy is improved.

In addition, the minimum value selector 78 and the minimum value selector 88 are comparisons that are pressure control means for calculating the control target value of the compressor 9 within a range that does not exceed the upper limit values of both the downstream upper limit value and the upstream upper limit value. Part 90 is configured.

Next, with reference to FIG. 3, the control target value calculation procedure shown in FIG. 2 will be described with reference to the flowchart of FIG.
First, in step S1, the target Pb is calculated by the target Pb conversion unit 71. Next, in step S2, it is determined whether or not the target Pb calculated in step S1 exceeds the upper limit set by the target Pb upper limit setting unit 69. If it exceeds, the target Pb is limited to an upper limit value or an arbitrary value below it, and the process proceeds to step S4. If not, the process proceeds to step S4 with Pb calculated in step S1, and in step S4. A target P2 is calculated.
In the calculation of P2, pressure conversion is performed by adding the conversion amount set by the target P2 conversion amount setting unit 73 to the target Pb. In the next step S5, the target pressure ratio (P2 / P1) is calculated. The target pressure ratio (P2 / P1) is calculated by obtaining the atmospheric pressure information from the atmospheric pressure sensor 63 and dividing the target P2 calculated in step S4.

Next, in step S6, it is determined whether the pressure ratio calculated in step S5 exceeds the upper limit set from the surge line of the compressor 9. If not, the process proceeds to step S8, and the target pressure ratio calculated in step S5 is determined as a control target value.
If it is determined in step S6 that it exceeds the target pressure ratio, the target pressure ratio is limited to an upper limit value set from the compressor surge line or an arbitrary value less than that in step S7. And it progresses to step S8 and the limited upper limit value or limit value is determined as a control target value.

  When the control target value is determined, the waste gate valve control unit 100 adds the P2 / P1 value in the operating state to the pressure ratio (P2 / P1) that is the control target value, that is, on the downstream side of the throttle valve 51. The calculated value of P2 / P1 based on the P2 detection value by the downstream pressure sensor 55 that detects the intake pressure and the P1 detection value by the upstream pressure sensor 53 that detects the intake pressure upstream of the throttle valve 51 is a control target value. The opening degree of the waste gate valve 43 is feedback-controlled so that the pressure ratio is as follows.

  According to the above embodiment, the pressure ratio (P2 / P1) of the control target value is set to the upper limit value based on the surging line of the compressor 9 and the allowable torque of the transmission or the knocking limit of the internal combustion engine as an element of the transmission or the internal combustion engine. In addition to the upper limit value based on the exhaust gas performance and the upper limit value based on the required conditions such as the strength limit of the drive shaft and the differential mechanism in the power transmission system. The fuel consumption performance and the acceleration performance can be improved because the operation is performed in consideration of the allowable torque of the transmission and the knocking limit of the internal combustion engine while suppressing the surging.

  That is, if control of the control target value only by the surge line that suppresses the surging of the compressor 9 is performed, the operation may be performed even if there is no allowance considering the allowable torque of the transmission, the knocking limit of the engine, etc. However, there is a possibility that the vehicle will be limited in spite of a margin, and there is a possibility that the acceleration performance and the fuel efficiency are likely to deteriorate during the transition, and that the strength problem in the mission and engine may occur. However, according to the present embodiment, such a problem can be solved.

Next, another embodiment will be described with reference to FIGS.
4 is a block diagram showing the configuration of the ECU 57 corresponding to FIG. 2, and FIG. 5 is a control flow diagram for setting the target pressure corresponding to FIG.
4 and 5, the control target value is not the pressure ratio but the upstream intake pressure P2 upstream of the throttle valve 51, and the control target value is calculated with respect to FIGS. The waste gate valve controller 100 controls the opening degree of the waste gate valve 43.

The supercharger control unit 101 is similar to the configuration of the supercharger control unit 65 of FIG. 2. The target Pb upper limit value setting unit 69, the target pressure ratio upper limit value setting unit 75, the downstream upper limit value and the upstream upper limit And a comparison unit 90 that calculates a control target value of the compressor 9 within a range not exceeding both upper limit values.
The description about these will be omitted with the same reference numerals.
The difference is that in the configuration of the supercharger control means 65 of FIG. 2, the ratio is calculated by dividing by the atmospheric pressure (P1) because of the pressure ratio, but in the present embodiment, the divider 84 is used. Not equipped.

  In the supercharger control means 65, the target pressure ratio upper limit value setting unit 75 is provided to set the target pressure ratio upper limit value. However, in the present embodiment, the target pressure upper limit value setting unit 102 is provided to provide the target pressure ratio upper limit value. The upper limit value of (P2) is set. In this setting, the target pressure ratio upper limit value map 76 of the target pressure ratio upper limit value setting unit 75 of the supercharger control means 65 is set based on the atmospheric pressure from the target pressure ratio upper limit value set based on the surging line of the compressor 9 ( Set by calculating the upper pressure limit (by multiplying by atmospheric pressure).

  As for the control flow, as shown in FIG. 5, only the target pressure ratio (P2 / P1) in step S5 is not calculated with respect to the control flow of FIG. 3, and the other flows are the same. The same step number is attached and explanation is omitted.

  According to the present embodiment described above, the upstream side intake pressure (P2) of the control target value is set to the upper limit value based on the surging line of the compressor 9 and the transmission or internal combustion engine as in the above-described embodiments of FIGS. Since the calculation is performed within a range that does not exceed both the upper limit value and the upper limit value based on the required conditions such as the allowable torque of the transmission or the knocking limit of the internal combustion engine, the allowable torque of the transmission is suppressed while suppressing the surging of the compressor 9. Since the engine is operated in consideration of the knocking limit of the internal combustion engine, fuel efficiency and acceleration performance can be improved.

In this embodiment, since the upstream intake pressure (P2) is directly controlled as the target value instead of the pressure ratio (P2 / P1) as the control target value, the control is simplified, so that the waste gate valve 43 The operation responsiveness can be improved.
In addition, although the gasoline engine was demonstrated in the present Example, the same effect is acquired even if it is a diesel engine, for example.

  According to one embodiment of the present invention, the upstream side intake pressure (P2) or the intake pressure ratio (P2 / P1) of the control target value is determined based on the upper limit value based on the surging line of the compressor 9 and the request of the transmission or the internal combustion engine. The upper limit value is calculated within a range that does not exceed both upper limit values, so that operation that takes into account the demands of the transmission or the internal combustion engine, for example, the allowable torque of the transmission or the knocking limit of the internal combustion engine, while suppressing the surging of the compressor. As a result, fuel efficiency and acceleration performance can be improved. For this reason, it is effective for application to supercharging pressure control of an internal combustion engine with an exhaust supercharger.

1 Internal combustion engine
3 Intake passage 7 Exhaust supercharger 9 Compressor 11 Intercooler 15 Surge tank 35 Exhaust passage 37 Turbine 41 Bypass passage 43 Wastegate valve 49 Air flow meter 51 Throttle valve 53 Upstream pressure sensor 55 Downstream pressure sensor 57 ECU (electronic control unit) )
61 Engine Rotation Sensor 63 Atmospheric Pressure Sensor 65, 101 Supercharger Control Unit 69 Target Pb Upper Limit Setting Unit (First Upper Limit Calculation Unit)
71 Target Pb converter (first target intake pressure calculating means)
73 Target P2 conversion amount setting unit 75 Target pressure ratio upper limit setting unit (second upper limit calculating means)
78, 88 Minimum value selector 82 Conversion unit (second target intake pressure calculation means)
90 Comparison part (pressure control means)
100 Wastegate valve control unit 102 Target pressure upper limit value setting unit M1 Upper limit value line M2 Surge line

Claims (4)

A turbocharger compressor that is rotated by a turbine provided in an exhaust passage of the internal combustion engine to compress intake air;
A throttle valve that is provided on the downstream side of the intake passage of the compressor and adjusts the amount of intake air supplied to the internal combustion engine;
First target intake pressure calculating means for calculating a first target intake pressure on the downstream side of the target throttle valve from the load and rotation of the internal combustion engine;
A second target intake pressure calculating means for calculating a second target intake pressure upstream of the throttle valve based on the first target intake pressure,
A supercharger control means for calculating a control target value of the compressor based on the second target intake pressure or a target pressure ratio which is a ratio of the second target intake pressure and the atmospheric pressure;
A control device for an internal combustion engine with a supercharger comprising:
The supercharger control means includes
First upper limit value calculating means for calculating an upper limit value of the first target intake pressure based on a combustion state of the internal combustion engine or a limit point of a driving device connected to the internal combustion engine;
A second upper limit value calculating means that is calculated based on a surging line of the compressor and that calculates an upper limit value of the second target intake pressure or the target pressure ratio;
Pressure control means for calculating a control target value of the compressor within a range not exceeding both the first and second upper limit values and controlling the rotation speed of the compressor;
The pressure control means compares the first target intake pressure with the upper limit value of the first target intake pressure calculated by the first upper limit value calculation means, and based on a smaller value, the second target intake pressure. An intake pressure or the target pressure ratio is calculated, and the second target intake pressure or the target pressure ratio calculated by the comparison and the second target intake pressure or the target calculated by the second upper limit value calculating means are calculated. A control device for an internal combustion engine with a supercharger, wherein the control device compares a target pressure ratio and outputs a small value as a control target value of the compressor . The internal combustion engine
E Bei intake air amount acquisition means for measuring or estimating the amount of intake air sucked into the internal combustion engine,
The second upper limit value calculating means calculates an intake air amount passing through the compressor based on the intake air amount measured by the intake air amount acquiring means, and based on the intake air amount and a surge line of the compressor. 2. The control device for an internal combustion engine with a supercharger according to claim 1 , wherein an upper limit value of the target intake pressure of 2 or the target pressure ratio is calculated. According to claim 1 or 2, characterized in that it is defined by the permissible torque of the drive force transmission means for transmitting a driving force of the first upper limit value of the target intake pressure is connected to at least the internal combustion engine the internal combustion engine Control device for an internal combustion engine with a supercharger. The upper limit value of the second target intake pressure or the target pressure ratio is any one of claims 1-3, characterized in that with respect to the surge line of a compressor is the value set comprise a predetermined allowance The control device for an internal combustion engine with a supercharger according to claim 1.

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