JP6005543B2 - Control device for supercharged engine - Google Patents

Description

  The present invention relates to an engine equipped with a supercharger that boosts the intake air of an engine, and includes an exhaust gas recirculation device that recirculates part of the exhaust of the engine to the engine. The present invention relates to a control device for a supercharged engine.

  Conventionally, this type of technology has been employed in, for example, automobile engines. An exhaust gas recirculation (EGR) device guides part of exhaust gas after combustion discharged from an engine combustion chamber to an exhaust passage as EGR gas to the intake passage through the EGR passage and flows through the intake passage. It is mixed with intake air and returned to the combustion chamber. EGR gas flowing through the EGR passage is adjusted by an EGR valve provided in the EGR passage. By this EGR, nitrogen oxide (NOx) in the exhaust gas can be mainly reduced, and fuel efficiency can be improved at the time of partial load of the engine.

  The engine exhaust is either free of oxygen or lean. Therefore, by mixing a part of the exhaust gas with the intake air by EGR, the oxygen concentration in the intake air decreases. For this reason, in the combustion chamber, fuel burns in a state where the oxygen concentration is low, so that the peak temperature at the time of combustion is lowered and generation of NOx can be suppressed. In a gasoline engine, the pumping loss of the engine can be reduced even when the throttle valve is closed to some extent without increasing the oxygen content in the intake air by EGR.

  Here, recently, in order to further improve the fuel efficiency of the engine, it is conceivable to perform EGR in the entire operation region of the engine, and it is required to realize a large amount of EGR. In order to realize a large amount of EGR, it is necessary to enlarge the inner diameter of the EGR passage or increase the flow passage opening area of the valve body or the valve seat of the EGR valve as compared with the conventional technology.

  By the way, it is well known that an engine equipped with a supercharger is provided with an EGR device. The following Patent Document 1 describes an EGR device for an engine equipped with this type of supercharger. This engine includes a turbocharger that includes a turbine provided in an exhaust passage and a compressor provided in an intake passage and driven by the turbine. An EGR passage is provided between the downstream side of the turbine in the exhaust passage and the upstream side of the compressor in the intake passage, and an EGR valve is provided in the EGR passage (low pressure loop EGR device). In this EGR device, an intake throttle valve is provided in the intake passage upstream from the outlet of the EGR passage, and a negative pressure is generated in the intake passage by restricting the opening of the intake throttle valve, and the EGR passage moves from the outlet of the EGR passage to the intake passage. A lot of gas is made to flow. Also, during engine deceleration operation, the opening of the intake throttle valve is limited to the lower limit, limiting the generation of negative pressure upstream of the compressor that increases when the intake throttle valve closes too much, and EGR gas is excessively introduced into the intake passage. It is designed to prevent inflow.

JP 2012-17708 A

  However, in the engine with a supercharger described in Patent Document 1, the path of the intake passage from the outlet of the EGR passage to the throttle valve is relatively long. Therefore, when the engine starts acceleration operation from the state where no EGR gas remains in the intake passage upstream from the throttle valve, and the EGR valve opens and restarts EGR, the engine flows from the outlet of the EGR passage to the intake passage. It took some time until EGR gas first reached the combustion chamber via the throttle valve, resulting in a delay in arrival. For this reason, the EGR rate in the combustion chamber becomes insufficient until the EGR gas reaches the combustion chamber for the first time. As a result, the engine torque is increased when the EGR gas reaches the combustion chamber for the first time after the acceleration of the engine. There was a possibility that drivability would deteriorate due to a step. In particular, when a large amount of EGR is assumed, the EGR rate fluctuates greatly before and after the EGR gas first reaches the combustion chamber, and there is a concern that the torque step becomes larger.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to enter the combustion chamber when the engine starts an acceleration operation from a state in which no EGR gas remains in the intake passage and restarts EGR. It is an object to provide a control device for an engine with a supercharger that can prevent a torque step from occurring in the engine due to a delay in arrival of EGR gas.

In order to achieve the above object, an invention according to claim 1 is provided between an intake passage and an exhaust passage of an engine, and a supercharger for boosting intake air in the intake passage, and a supercharger, Including a compressor disposed in the intake passage, a turbine disposed in the exhaust passage, and a rotating shaft that connects the compressor and the turbine so as to be integrally rotatable, and provided in the intake passage downstream of the compressor, An intake air amount adjusting valve for adjusting the amount, an exhaust gas recirculation passage for flowing a part of the exhaust gas discharged from the combustion chamber of the engine to the exhaust passage as an exhaust gas recirculation gas to the intake passage, and returning the exhaust gas to the combustion chamber; exhaust and recirculation system, exhaust gas recirculation passage including the exhaust gas recirculation valve for regulating the exhaust recirculation gas in, the inlet is connected to the exhaust passage downstream of the turbine, the outlet air And it is connected from control valve and the compressor in the intake passage upstream, and an output adjusting means for adjusting the output of the engine, the operating condition detecting means for detecting operating conditions of the engine, the operating state detected The control means for controlling the exhaust gas recirculation valve and the output adjusting means based on the control means, and the control means for controlling the opening of the exhaust gas recirculation valve based on the operating state detected during the acceleration operation or the steady operation of the engine, and stopping the engine The exhaust gas recirculation valve is controlled to close at the time of engine operation or deceleration operation, and the intake air amount adjustment valve is opened during engine acceleration operation or steady operation, and is closed during engine stop or deceleration operation. In the engine control device with a supercharger provided, the control means is such that the exhaust gas recirculation gas does not remain in the intake passage upstream of the intake air amount adjustment valve during acceleration operation of the engine When it is determined, an exhaust recirculation gas from the exhaust gas recirculation valve is opened is controlled the output adjusting means in order to prevent the torque down of the engine that occurs at the time of their first arrival in the combustion chamber, a time of acceleration operation of the engine When it is determined that the exhaust gas recirculation gas remains in the intake passage upstream of the intake air amount adjustment valve, the opening of the exhaust gas recirculation valve from the closed state is delayed until the remaining exhaust gas recirculation gas decreases below a predetermined value. The purpose is to make it.

  According to the configuration of the above invention, in the engine with a supercharger, the inlet of the exhaust gas recirculation passage is connected to the exhaust passage downstream of the turbine, and the outlet of the exhaust gas recirculation passage is connected to the intake passage upstream of the compressor. The path of the intake passage from the outlet of the exhaust gas recirculation passage to the intake air amount adjustment valve is relatively long. Also, during acceleration or steady operation of the engine, the exhaust recirculation valve is controlled to open based on the detected operating state, and when the engine is stopped or decelerated, the exhaust recirculation valve is controlled to close by the control means. Is done. For this reason, if the exhaust gas recirculation gas does not remain in the intake passage upstream from the intake air amount adjustment valve during the acceleration operation of the engine, the intake air amount adjustment valve is opened and the exhaust gas recirculation valve is controlled to open before the exhaust gas is exhausted. There will be a delay before the reflux gas first reaches the combustion chamber. When the exhaust gas recirculation gas reaches the combustion chamber for the first time, the ratio of the exhaust gas recirculation gas to the intake air in the combustion chamber becomes excessive as compared to before the exhaust gas recirculation gas reaches, causing torque reduction in the engine and reducing the engine torque. A step will occur. Therefore, according to the configuration of the above invention, when the control means determines that the exhaust gas recirculation gas does not remain in the intake passage upstream of the intake air amount adjustment valve during the acceleration operation of the engine, the exhaust gas recirculation valve is The output adjusting means is controlled by the control means in order to prevent engine torque reduction that occurs when the exhaust gas recirculation gas reaches the combustion chamber for the first time after opening. Therefore, during the acceleration operation of the engine, the torque reduction of the engine when the exhaust gas recirculation gas newly flows from the exhaust gas recirculation passage to the intake passage and first reaches the combustion chamber is suppressed.

  In order to achieve the above object, according to a second aspect of the present invention, in the first aspect of the present invention, the output adjusting means is an intake air amount adjusting valve, and the control means is an exhaust recirculation valve opened. Until the exhaust gas recirculation gas reaches the combustion chamber for the first time, the intake air amount adjustment valve is controlled to close to a predetermined target opening, and after the exhaust gas recirculation gas first reaches the combustion chamber, the intake air amount adjustment valve is controlled. The purpose is to control the target opening.

  According to the configuration of the above invention, in the operation of the invention according to claim 1, the intake air amount adjustment valve is controlled by the control means until the exhaust gas recirculation gas reaches the combustion chamber first after the exhaust gas recirculation valve opens. After the exhaust recirculation gas first reaches the combustion chamber, the intake air amount adjustment valve is controlled to the target opening by the control means. Accordingly, the amount of intake air supplied to the combustion chamber is reduced until the exhaust gas recirculation gas reaches the combustion chamber first, and the combustion of the air-fuel mixture is suppressed, so that the exhaust gas recirculation gas reaches the combustion chamber first. The torque reduction of the engine is suppressed.

  In order to achieve the above object, according to a third aspect of the present invention, in the first aspect of the present invention, the output adjusting means is an intake air amount adjusting valve, and the control means is an exhaust recirculation valve opened. Until the exhaust gas recirculation gas reaches the combustion chamber for the first time, the intake air amount adjustment valve is controlled to a predetermined target opening degree. The purpose is also to control the opening side.

  According to the configuration of the above invention, in the operation of the invention according to claim 1, the intake air amount adjustment valve is controlled by the control means until the exhaust gas recirculation gas reaches the combustion chamber first after the exhaust gas recirculation valve opens. After the exhaust gas recirculation gas reaches the combustion chamber for the first time, the intake air amount adjustment valve is controlled to the opening side of the target opening by the control means. Therefore, the amount of intake air supplied to the combustion chamber until the exhaust gas recirculation gas reaches the combustion chamber for the first time is reduced more than after the exhaust gas recirculation gas first reaches the combustion chamber, and the combustion of the air-fuel mixture becomes relative. As a result, the torque reduction of the engine when the exhaust gas recirculation gas first reaches the combustion chamber can be suppressed.

  In order to achieve the above object, according to a fourth aspect of the present invention, in the first aspect of the present invention, the output adjusting means is an ignition device for igniting an air-fuel mixture sucked into the combustion chamber. Controls the ignition timing by the igniter until the exhaust gas recirculation gas reaches the combustion chamber for the first time after the exhaust gas recirculation valve opens, so that the exhaust gas recirculation gas enters the combustion chamber. The purpose is to control the ignition timing by the ignition device to the target ignition timing after the first arrival.

  According to the configuration of the above invention, in the operation of the invention according to claim 1, the ignition timing by the ignition device is predetermined by the control means until the exhaust gas recirculation gas reaches the combustion chamber for the first time after the exhaust gas recirculation valve is opened. The ignition timing by the ignition device is controlled to the target ignition timing by the control means after the exhaust gas recirculation gas reaches the combustion chamber for the first time. Therefore, the ignition timing of the air-fuel mixture in the combustion chamber is delayed until the exhaust gas recirculation gas reaches the combustion chamber first, and the combustion of the air-fuel mixture is suppressed, so that the exhaust gas recirculation gas reaches the combustion chamber first. The torque reduction of the engine when it is done is suppressed.

In order to achieve the above object, according to a fifth aspect of the present invention, in the first aspect of the present invention, the output adjusting means introduces fresh air into the intake passage downstream of the intake air amount adjusting valve. The control means reduces the introduction of fresh air by the fresh air introduction device from a predetermined target amount until the exhaust gas recirculation gas reaches the combustion chamber for the first time after the exhaust gas recirculation valve opens, and the exhaust gas recirculation The purpose is to increase the introduction of fresh air by the fresh air introduction device to a predetermined target amount after the gas first reaches the combustion chamber.

  According to the configuration of the above invention, in the operation of the invention according to claim 1, the introduction of fresh air by the fresh air introduction device is performed until the exhaust gas recirculation gas first reaches the combustion chamber after the exhaust gas recirculation valve is opened. After the exhaust gas recirculation gas first reaches the combustion chamber, the introduction of fresh air by the fresh air introduction device is increased to the prescribed target amount by the control means. Therefore, the total amount of intake air and fresh air supplied to the combustion chamber until the exhaust gas recirculation gas reaches the combustion chamber for the first time is reduced, and combustion of the air-fuel mixture is suppressed, so that the exhaust gas recirculation gas enters the combustion chamber. Torque down of the engine when it reaches first is suppressed.

  In order to achieve the above object, according to a sixth aspect of the present invention, in the first aspect of the present invention, the output adjusting means introduces fresh air into the intake passage downstream of the intake amount adjusting valve. The control means controls the introduction of fresh air by the fresh air introduction device to a predetermined target amount until the exhaust gas recirculation gas reaches the combustion chamber for the first time after the exhaust gas recirculation valve opens, and the exhaust gas recirculation gas After reaching the combustion chamber for the first time, the purpose is to increase the introduction of fresh air by the fresh air introduction device beyond a predetermined target amount.

  According to the configuration of the above invention, in the operation of the invention according to claim 1, the introduction of fresh air by the fresh air introduction device is performed until the exhaust gas recirculation gas first reaches the combustion chamber after the exhaust gas recirculation valve is opened. After the exhaust gas recirculation gas reaches the combustion chamber for the first time by the control means, the introduction of fresh air by the fresh air introduction device is increased from the prescribed target quantity by the control means. Therefore, the total amount of intake air and fresh air supplied to the combustion chamber until the exhaust gas recirculation gas reaches the combustion chamber for the first time is reduced more than after the exhaust gas recirculation gas first reaches the combustion chamber. As a result, the engine torque is reduced when the exhaust gas recirculation gas first reaches the combustion chamber.

  According to the invention described in any one of claims 1 to 6, when the engine starts the acceleration operation from the state where the EGR gas does not remain in the intake passage and restarts the EGR, the EGR gas to the combustion chamber is It is possible to prevent a torque step from being generated in the engine due to the arrival delay, and it is possible to prevent deterioration of engine drivability.

The schematic block diagram which shows the engine system which concerns on 1st Embodiment and contains the EGR apparatus of the engine with a supercharger. FIG. 4 is an enlarged cross-sectional view showing a part of the EGR passage where an EGR valve is provided according to the embodiment. 7 is a flowchart showing an example of processing contents for calculating a residual EGR gas-containing intake air amount including EGR gas remaining in an intake passage upstream of a throttle valve in the early stage of rapid engine deceleration according to the embodiment. The map referred in order to calculate the residual EGR gas containing intake air amount concerning the embodiment. The flowchart which shows an example of the processing content for calculating the residual EGR gas containing intake air quantity in the intake passage upstream from a throttle valve after rapid deceleration of an engine according to the same embodiment. The map referred to in order to calculate the throttle valve passage intake air amount according to the embodiment. The flowchart which shows an example of the processing content of EGR control and throttle control concerning the embodiment. The map referred in order to obtain | require a throttle opening correction coefficient concerning the embodiment. The time chart which shows an example of the behavior of various parameters concerning the embodiment. The flowchart which shows an example of the processing content of EGR control and throttle control concerning 2nd Embodiment. The map referred in order to obtain | require a throttle opening correction coefficient concerning the embodiment. The flowchart which shows an example of the content of a process concerning 3rd Embodiment for adjusting the output of an engine. The map referred in order to obtain | require a retardation correction coefficient concerning the embodiment. The time chart which shows an example of the behavior of various parameters concerning the embodiment. The schematic block diagram which shows the engine system which concerns on 4th Embodiment and contains the EGR apparatus of the engine with a supercharger. The flowchart which shows an example of the processing content for adjusting the output of an engine according to the embodiment. The map referred to in order to obtain a fresh air correction coefficient according to the embodiment. The flowchart which shows an example of the processing content concerning 5th Embodiment for adjusting the output of an engine. The map referred to in order to obtain a fresh air correction coefficient according to the embodiment.

<First Embodiment>
Hereinafter, a first embodiment of a control device for a supercharged engine according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an engine system including an exhaust gas recirculation device (EGR device) for an engine with a supercharger in this embodiment. This engine system includes a reciprocating engine 1. An intake passage 3 is connected to the intake port 2 of the engine 1, and an exhaust passage 5 is connected to the exhaust port 4. An air cleaner 6 is provided at the inlet of the intake passage 3. A supercharger 7 for boosting the intake air in the intake passage 3 is provided in the intake passage 3 downstream of the air cleaner 6 between the exhaust passage 5 and the intake passage 3.

  The supercharger 7 includes a compressor 8 disposed in the intake passage 3, a turbine 9 disposed in the exhaust passage 5, and a rotating shaft 10 that connects the compressor 8 and the turbine 9 so as to be integrally rotatable. The supercharger 7 rotates the turbine 9 by the exhaust gas flowing through the exhaust passage 5 and integrally rotates the compressor 8 via the rotary shaft 10 to boost the intake air in the intake passage 3, that is, perform supercharging. It is like that.

  An exhaust bypass passage 11 that bypasses the turbine 9 is provided in the exhaust passage 5 adjacent to the supercharger 7. A waste gate valve 12 is provided in the exhaust bypass passage 11. By adjusting the exhaust gas flowing through the exhaust bypass passage 11 by the waste gate valve 12, the exhaust gas flow rate supplied to the turbine 9 is adjusted, the rotational speeds of the turbine 9 and the compressor 8 are adjusted, and supercharging by the supercharger 7 is performed. The pressure is adjusted.

  In the intake passage 3, an intercooler 13 is provided between the compressor 8 of the supercharger 7 and the engine 1. The intercooler 13 is for cooling the intake air that has been pressurized by the compressor 8 to a high temperature. A surge tank 3 a is provided in the intake passage 3 between the intercooler 13 and the engine 1. An electronic throttle device 14 that is an electric throttle valve is provided in the intake passage 3 downstream from the intercooler 13 and upstream from the surge tank 3a. The electronic throttle device 14 corresponding to the intake air amount adjusting valve of the present invention includes a butterfly-type throttle valve 21 disposed in the intake passage 3, a step motor 22 for opening and closing the throttle valve 21, And a throttle sensor 23 for detecting an opening (throttle opening) TA. The electronic throttle device 14 is configured such that the opening degree of the throttle valve 21 is adjusted by opening and closing the throttle valve 21 by a step motor 22 in accordance with the operation of the accelerator pedal 26 by the driver. As the configuration of the electronic throttle device 14, for example, the basic configuration of the “throttle device” described in FIGS. 1 and 2 of JP 2011-252482 A can be employed. The exhaust passage 5 downstream from the turbine 9 is provided with a catalytic converter 15 as an exhaust catalyst for purifying exhaust.

  The engine 1 is provided with an injector 25 for injecting and supplying fuel to the combustion chamber 16. Fuel is supplied to the injector 25 from a fuel tank (not shown). The engine 1 is provided with a spark plug 29 corresponding to each cylinder. Each spark plug 29 is ignited by receiving a high voltage output from the igniter 30. The ignition timing of each spark plug 29 is determined by the high voltage output timing from the igniter 30. The spark plug 29 and the igniter 30 constitute an ignition device.

  In this embodiment, the EGR device for realizing a large amount of EGR causes a part of the exhaust discharged from the combustion chamber 16 of the engine 1 to the exhaust passage 5 to flow into the intake passage 3 as EGR gas and to be returned to the combustion chamber 16. An exhaust gas recirculation passage (EGR passage) 17 and an exhaust gas recirculation valve (EGR valve) 18 provided in the EGR passage 17 for adjusting the flow of EGR gas in the EGR passage 17 are provided. The EGR passage 17 is provided between the exhaust passage 5 downstream from the catalytic converter 15 and the intake passage 3 upstream from the compressor 8. That is, a part of the exhaust gas flowing through the exhaust passage 5 flows as EGR gas to the intake passage 3 through the EGR passage 17 and recirculates to the combustion chamber 16, so that the outlet 17 a of the EGR passage 17 has an intake passage 3 upstream of the compressor 8. Connected to. Further, the inlet 17 b of the EGR passage 17 is connected to the exhaust passage 5 downstream from the catalytic converter 15.

  The EGR passage 17 is provided with an EGR cooler 20 for cooling the EGR gas flowing through the passage 17. In this embodiment, the EGR valve 18 is disposed in the EGR passage 17 downstream of the EGR cooler 20.

  FIG. 2 is an enlarged sectional view showing a part of the EGR passage 17 where the EGR valve 18 is provided. As shown in FIGS. 1 and 2, the EGR valve 18 is constituted by a poppet valve and an electric valve. That is, the EGR valve 18 includes a valve body 32 that is driven by the step motor 31. The valve body 32 has a substantially conical shape, and is provided so as to be seated on a valve seat 33 provided in the EGR passage 17. The step motor 31 includes an output shaft 34 that is configured to be capable of linearly reciprocating (stroke), and a valve body 32 is fixed to the tip of the output shaft 34. The output shaft 34 is supported by a housing constituting the EGR passage 17 via a bearing 35. The opening degree of the valve body 32 relative to the valve seat 33 is adjusted by moving the output shaft 34 of the step motor 31 by a stroke. The output shaft 34 of the EGR valve 18 is provided so as to be able to perform a stroke movement by a predetermined stroke L1 from a fully closed state in which the valve body 32 is seated on the valve seat 33 to a fully open state in which the valve body 32 contacts the bearing 35. . In this embodiment, in order to realize a large amount of EGR, the opening area of the valve seat 33 is enlarged as compared with the conventional technique. Accordingly, the valve body 32 is enlarged. As a configuration of the EGR valve 18, for example, a basic configuration of “EGR valve” described in FIG. 1 of JP 2010-275941 A can be adopted.

  In this embodiment, in order to execute fuel injection control, ignition timing control, intake air amount control, EGR control, and the like according to the operating state of the engine 1, the injector 25, the igniter 30, the step motor 22 of the electronic throttle device 14, and The step motor 31 of the EGR valve 18 is controlled by an electronic control unit (ECU) 50 in accordance with the operating state of the engine 1. The ECU 50 stores in advance a central processing unit (CPU), a predetermined control program and the like, various memories for temporarily storing a calculation result of the CPU, and the like, an external input circuit connected to these parts, and an external And an output circuit. The ECU 50 corresponds to the control means of the present invention. An igniter 30, an injector 25, and step motors 22 and 31 are connected to the external output circuit. Various sensors 27 and 51 to 55 corresponding to the operating state detecting means of the present invention for detecting the operating state of the engine 1 including the throttle sensor 23 are connected to the external input circuit so that various engine signals are input. It has become.

  Here, in addition to the throttle sensor 23, an accelerator sensor 27, a brake sensor 28, an intake pressure sensor 51, a rotation speed sensor 52, a water temperature sensor 53, an air flow meter 54, and an air-fuel ratio sensor 55 are provided as various sensors. The accelerator sensor 27 detects an accelerator opening ACC that is an operation amount of the accelerator pedal 26. The accelerator pedal 26 corresponds to an operating means for operating the operation of the engine 1. The brake sensor 28 corresponds to the brake detection means of the present invention that detects that the brake pedal 36 has been depressed. The engine 1 is mounted on a vehicle as a drive source, and the brake pedal 36 is depressed by a driver to stop the vehicle. The intake pressure sensor 51 detects the intake pressure PM in the surge tank 3a. That is, the intake pressure sensor 51 detects the intake pressure PM in the intake passage 3 (surge tank 3a) downstream from the position where EGR gas flows from the EGR passage 17 into the intake passage 3. The rotational speed sensor 52 detects the rotational angle (crank angle) of the crankshaft 1a of the engine 1 and detects the change in the crank angle as the rotational speed (engine rotational speed) NE of the engine 1. The water temperature sensor 53 detects the cooling water temperature THW of the engine 1. The air flow meter 54 detects the intake air amount Ga flowing through the intake passage 3 immediately downstream of the air cleaner 6. The air-fuel ratio sensor 55 is provided in the exhaust passage 5 immediately upstream of the catalytic converter 15, and detects the air-fuel ratio A / F in the exhaust.

  In this embodiment, a vehicle speed sensor 56 is provided in a vehicle (not shown) on which the engine 1 is mounted, and the vehicle speed sensor 56 is connected to an external input circuit of the ECU 50. The vehicle speed sensor 56 is for detecting the vehicle speed SPD of the vehicle.

  In this embodiment, the ECU 50 controls the EGR valve 18 in order to control the EGR in accordance with the operation state of the engine 1 in the entire operation region of the engine 1. Further, the ECU 50 controls the EGR valve 18 to open based on the operating state detected during the acceleration operation or the steady operation of the engine 1 and controls the EGR valve 18 to close when the engine 1 is stopped or decelerated. It has become.

  In this embodiment, the ECU 50 controls the electronic throttle device 14 based on the accelerator opening ACC in order to drive the engine 1 in response to a driver's request. Further, the ECU 50 controls the opening of the electronic throttle device 14 based on the accelerator opening ACC during the acceleration operation or the steady operation of the engine 1 and closes the electronic throttle device 14 when the engine 1 is stopped or decelerated. It has become. As a result, the throttle valve 21 is opened during acceleration or steady operation of the engine 1 and closed when the engine 1 is stopped or decelerated.

  In the engine 1 provided with the supercharger 7 of this embodiment, an outlet 17a of the EGR passage 17 is provided in the intake passage 3 upstream from the compressor 8 to introduce EGR gas into the intake passage 3. Further, since the path of the intake passage 3 from the outlet 17a of the EGR passage 17 to the electronic throttle device 14 (throttle valve 21) is relatively long, the EGR gas flowing out from the outlet 17a to the intake passage 3 passes through the throttle valve 21. Some time lag may occur. Further, when the engine 1 is decelerating, the electronic throttle device 14 is controlled to be closed, so that EGR gas may stay or remain in the intake passage 3 upstream of the throttle valve 21 and an EGR gas attenuation delay may occur. . On the other hand, immediately after the engine 1 is decelerated from the supercharging by the supercharger 7 with the EGR cut (EGR gas supply cut off), the EGR gas reaches the vicinity of the air cleaner 6 upstream from the outlet 17a of the EGR passage 17. May flow backward. Accordingly, when the acceleration operation of the engine 1 is started and the EGR is restarted from that state, the EGR gas may become excessive by the amount of the backflowed EGR gas or the remaining EGR gas. When the excess EGR gas reaches the combustion chamber 16, the combustibility of the fuel deteriorates for a moment, and the engine 1 may be suddenly torqued down. Further, when EGR is resumed from the state in which the EGR gas is not retained or remains in the intake passage 3 upstream of the throttle valve 21 and EGR is resumed, the intake passage 3 is discharged from the outlet 17a of the EGR passage 17. When the EGR gas that has flowed into the combustion chamber 16 first reaches the combustion chamber 16, torque reduction may occur in the engine 1. Therefore, in this embodiment, during the acceleration operation of the engine 1, the ECU 50 executes the following various controls in order to adjust the output of the engine 1 in accordance with the state of the EGR gas in the intake passage 3 upstream from the throttle valve 21. It is like that.

  In FIG. 3, an intake air amount including EGR gas remaining in the intake passage 3 upstream of the electronic throttle device 14 (throttle valve 21) at the early stage of sudden deceleration of the engine 1 (residual EGR gas-containing intake air amount at the early stage of deceleration) egrin is calculated. An example of the processing content for this is shown by a flowchart.

  When the processing shifts to this routine, first, at step 100, the ECU 50 takes in the engine rotational speed NE, the engine load KL, and the EGR rate Pegr based on the detected values of the intake pressure sensor 51, the rotational speed sensor 52, and the like. Here, the ECU 50 can determine the engine load KL based on the engine rotational speed NE and the intake pressure PM.

  Next, at step 110, the ECU 50 determines whether or not the engine 1 is suddenly decelerated from the EGR on region (EGR execution region). The ECU 50 makes this determination based on the accelerator opening degree ACC, the engine speed NE, and the like. If this determination result is negative, the ECU 50 once ends the process and returns the process to step 100. On the other hand, if the determination result is affirmative, the ECU 50 proceeds to step 120.

  In step 120, the ECU 50 stores the engine load KL immediately before the sudden deceleration of the engine 1 as "KL1" in the memory.

  Next, at step 130, the ECU 50 stores the EGR rate Pegr immediately before the sudden deceleration of the engine 1 as “Pegr1” in the memory.

  Next, in step 140, the ECU 50 determines the intake air amount containing EGR gas remaining in the intake passage 3 upstream of the throttle valve 21 in the early stage of sudden deceleration (residual EGR gas-containing intake air quantity in the early stage of deceleration) egrin immediately before the sudden deceleration. It calculates according to engine load KL1. This residual EGR gas-containing intake air amount egrin corresponds to a substitute amount used instead of the amount of EGR gas remaining in the intake passage 3 upstream of the throttle valve 21 (residual EGR gas amount) in the early stage of rapid deceleration. The ECU 50 can obtain the residual EGR gas-containing intake air amount egrin, for example, by referring to a map as shown in FIG. In this map, the relationship between the residual EGR gas-containing intake air amount egrin and the engine load KL1 immediately before sudden deceleration is set in advance. As can be seen from FIG. 4, when EGR is off (EGR is not executed), as shown by the broken line, the residual EGR gas-containing intake air amount egrin is “regardless of the magnitude of the engine load KL1 immediately before the rapid deceleration” 0 ". On the other hand, when EGR is on (EGR execution), the residual EGR gas-containing intake air amount egrin becomes a value equal to or greater than a predetermined value A, as shown by a thick line in FIG. Here, the residual EGR gas-containing intake air amount egrin is constant at a predetermined value A in an engine load KL1 region (non-supercharging region) where supercharging is not performed. In the engine load KL1 region (supercharging region) where supercharging is performed, the residual EGR gas-containing intake air amount egrin increases linearly from the predetermined value A as the engine load KL1 increases.

  Next, at step 150, the ECU 50 sets the EGR gas residual flag Xegrin to “1”. The flag Xegrin is set to “1” when EGR gas remains in the intake passage 3 upstream of the throttle valve 21 after deceleration of the engine 1, and is set to “0” when no EGR gas remains. Yes.

  Next, the ECU 50 sets the EGR ON permission flag Xegron to “0” in step 160, and then returns the process to step 100. This flag Xegron is set to “0” to prohibit EGR on when EGR gas remains in the intake passage 3 upstream of the throttle valve 21 after deceleration of the engine 1, and EGR on when no EGR gas remains. Is set to “1”.

  FIG. 5 shows an intake air amount including EGR gas remaining in the intake passage 3 upstream of the electronic throttle device 14 (throttle valve 21) after the engine 1 is suddenly decelerated (residual EGR gas-containing intake air amount after deceleration) egrin (i). An example of processing contents for calculation is shown by a flowchart. This residual EGR gas-containing intake air amount egrin (i) corresponds to a substitute dose of the residual EGR gas amount after deceleration.

  When the process proceeds to this routine, first, in step 200, the ECU 50 determines whether or not the EGR gas residual flag Xegrin is “1”, that is, whether or not EGR gas remains. When this determination result is negative, the ECU 50 once terminates the process and returns the process to step 200. On the other hand, if the determination result is affirmative, the ECU 50 proceeds to step 201.

  In step 201, the ECU 50 takes in the residual EGR gas-containing intake air amount egrin in the early stage of deceleration already calculated.

  Next, in step 202, the ECU 50 sets the residual EGR gas-containing intake air amount egrin at the initial stage of deceleration as the residual EGR gas-containing intake air amount egrin (i) after deceleration.

  Next, in step 203, the ECU 50 determines whether or not the EGR on permission flag Xegron is “1”, that is, whether or not EGR is on. If the determination result is negative, the ECU 50 proceeds to step 210. On the other hand, if the determination result is affirmative, the ECU 50 proceeds to step 204.

After step 203, in step 210, the ECU 50 determines whether or not the residual EGR gas-containing intake air amount egrin (i) is equal to or less than a predetermined value A. If this determination result is negative, the ECU 50 proceeds to step 204 as it is. On the other hand, if the determination result is affirmative, the ECU 50 sets the EGR on permission flag Xegron to “1” in step 211, and then proceeds to step 204.

  In step 204 after shifting from step 203, step 210 or step 211, the ECU 50 sets the current residual EGR gas-containing intake air amount egrin (i) as the previous residual EGR gas-containing intake air amount egrin (i-1).

  Next, in step 205, the ECU 50 takes in the engine rotational speed NE and the throttle opening TA based on the detection values of the rotational speed sensor 52 and the throttle sensor 23.

  Next, at step 206, the ECU 50 calculates the throttle valve passing intake air amount gata according to the engine rotational speed NE and the throttle opening degree TA. The ECU 50 can obtain the throttle valve passage intake air amount gata by referring to, for example, a map shown in FIG. In this map, the value of the throttle valve passage intake air amount gata with respect to the values of the engine speed NE and the throttle opening degree TA is set in advance. For example, as can be seen from FIG. 6, when the throttle opening degree TA becomes “3 °”, the throttle valve passing intake air amount gata increases very gradually as the engine rotational speed NE increases. On the other hand, when the throttle opening degree TA becomes “24 °”, the throttle valve passing intake air amount gata increases extremely rapidly as the engine rotational speed NE increases.

  Next, at step 207, the ECU 50 subtracts the throttle valve passage intake air amount gata from the previous residual EGR gas-containing intake air amount egrin (i-1), thereby obtaining the new residual EGR gas-containing intake air amount egrin (i ) Is calculated. That is, the ECU 50 calculates the residual EGR gas-containing intake air amount egrin (i) that decreases with the operation of the engine 1.

  Next, in step 208, the ECU 50 determines whether or not the residual EGR gas-containing intake air amount egrin (i) after the current deceleration is “0” or less. When the determination result is negative, the ECU 50 shifts the process to step 203 and repeats the processes of step 203 to step 208, step 210, and step 211. On the other hand, if this determination result is affirmative, the ECU 50 sets the EGR gas residual flag Xegrin to “0” in step 209 and then returns the process to step 200.

  According to the above control, when the engine 1 is accelerated after the engine 1 is suddenly decelerated, the residual EGR gas-containing intake air amount egrin (i) remaining in the intake passage 3 upstream of the throttle valve 21 is calculated, and the residual EGR Execution of EGR is prohibited (Xegron = 0) until the gas-containing intake air amount egrin (i) becomes equal to or less than a predetermined value A. It has become. That is, when the engine 1 shifts to the acceleration operation after the deceleration operation, the resumption of EGR is delayed until the residual EGR gas-containing intake air amount egrin (i) becomes equal to or less than the predetermined value A.

  Next, EGR control using the EGR valve 18 and throttle control using the electronic throttle device 14 will be described. FIG. 7 is a flowchart showing an example of processing contents of the EGR control and throttle control. In this embodiment, the electronic throttle device 14 is used as the output adjusting means of the present invention for adjusting the output of the engine 1.

  When the processing shifts to this routine, first, in step 400, the ECU 50 takes in the accelerator opening ACC based on the detection value of the accelerator sensor 27.

  Next, in step 401, the ECU 50 obtains a target throttle opening degree TTA corresponding to the accelerator opening degree ACC. The ECU 50 can obtain the target throttle opening degree TTA by referring to a predetermined map.

  Next, in step 402, the ECU 50 determines whether or not the above-described EGR gas residual flag Xegrin is “0”. If this determination result is negative, the ECU 50 proceeds to step 416 on the assumption that EGR gas remains in the intake passage 3 upstream from the electronic throttle device 14 (throttle valve 21). On the other hand, if this determination result is affirmative, the ECU 50 proceeds to step 403 on the assumption that no EGR gas remains in the intake passage 3 upstream of the throttle valve 21.

  Shifting from step 402, in step 416, the ECU 50 sets the target throttle opening degree TTA obtained this time as the final target throttle opening degree TTAc.

  Thereafter, in step 415, the ECU 50 controls the electronic throttle device 14 based on the final target throttle opening degree TTAc. As a result, the intake air amount Ga (intake air amount including residual EGR gas) supplied to the combustion chamber 16 is adjusted. Thereafter, the ECU 50 returns the process to step 400.

  On the other hand, in step 403 after shifting from step 402, the ECU 50 determines whether or not an EGR-on condition is satisfied. That is, the ECU 50 determines whether or not the operating state of the engine 1 satisfies a condition that can execute EGR. If this determination result is negative, the ECU 50 shifts the process to step 416 and executes the processes of step 416 and step 415 as described above. Thereby, the intake air amount Ga (the intake air amount not including EGR gas) supplied to the combustion chamber 16 is adjusted. In this case, since EGR cannot be executed, the ECU 50 controls the EGR valve 18 to be closed. On the other hand, when this determination result is affirmative, the ECU 50 proceeds to step 404 in order to execute EGR.

  In step 404, the ECU 50 takes in the throttle opening degree TA, the engine rotational speed NE, the engine load KL, and the cooling water temperature THW based on the detection values of the throttle sensor 23, the intake pressure sensor 51, the rotational speed sensor 52, and the water temperature sensor 53, respectively. . Here, the ECU 50 can determine the engine load KL based on the engine rotational speed NE and the intake pressure PM.

  Next, at step 405, the ECU 50 obtains the target opening degree Tegr of the EGR valve 18 according to the engine rotational speed NE, the engine load KL, the coolant temperature THW, and the like. The ECU 50 can obtain the target opening degree Tegr by referring to a predetermined map.

  Next, at step 406, the ECU 50 controls the EGR valve 18 to open based on the target opening degree Tegr.

  Next, in step 407, the ECU 50 obtains the ratio of EGR gas to the intake air amount Ga, that is, the EGR rate Pegr1. The ECU 50 can obtain the EGR rate Pegr1 from the values of the engine speed NE and the intake pressure PM.

  Next, at step 408, the ECU 50 obtains a throttle opening correction coefficient Kegr according to the EGR rate Pegr1. The ECU 50 can obtain the throttle opening correction coefficient Kegr by referring to the map shown in FIG. This map is set so that the throttle opening correction coefficient Kegr gradually decreases from “1.0” when the EGR rate Pegr1 becomes higher than a predetermined value.

  Next, in step 409, the ECU 50 obtains the intake air amount that has passed through the throttle valve 21, that is, the throttle valve passage intake air amount gata, according to the engine speed NE and the throttle opening degree TA. The ECU 50 can obtain the throttle valve passage intake air amount gata by referring to a predetermined map.

Next, at step 410, the ECU 50 obtains the EGR gas non-containing intake air amount gaegrin (i). This EGR gas-free intake amount gaegrin (i) means an intake amount that does not include EGR gas before the EGR gas is introduced into the intake passage 3 upstream of the throttle valve 21, and the intake passage upstream of the throttle valve 21. 3 space volume. The intake amount gaegrin (i) containing no EGR gas gradually decreases as the intake air passes through the throttle valve 21 after the valve opening after the EGR gas starts to be introduced into the intake passage 3. Accordingly, when the intake amount gaegrin (i) containing no EGR gas disappears, the EGR gas introduced into the intake passage 3 by opening the EGR valve 18 first passes through the throttle valve 21 and is introduced into the combustion chamber 16. Will mean the timing. The ECU 50 can obtain the EGR gas non-containing intake air amount gaegrin (i) by subtracting the throttle valve passage intake air amount gata from the previously obtained EGR gas non-containing air intake amount gaegrin (i-1). Here, the space volume of the intake passage 3 upstream of the throttle valve 21 can be applied as the initial value of the previous EGR gas-free intake amount gaegrin (i-1).

  Next, in step 411, the ECU 50 determines whether or not the EGR gas non-containing intake air amount gaegrin (i) is equal to or less than a predetermined value A1. The predetermined value A1 may be “0”, or may be set to a positive value that approximates “0” in consideration of intake pulsation and the like. If the determination result is affirmative, it is assumed that the EGR gas has first passed through the throttle valve 21 and reached the combustion chamber 16, and the ECU 50 proceeds to step 416, and step 416 and step 415 as described above. Execute the process. In this case, the throttle control by the electronic throttle device 14 is controlled to the target throttle opening degree TTA obtained by referring to the map. On the other hand, if this determination result is negative, the ECU 50 proceeds to step 412 assuming that the EGR gas has not passed through the throttle valve 21 first and has not reached the combustion chamber 16.

  In step 412, the ECU 50 corrects the target throttle opening degree TTA by the throttle opening degree correction coefficient Kegr. That is, the ECU 50 obtains the final target throttle TTAc by multiplying the target throttle opening degree TTA by the throttle opening degree correction coefficient Kegr.

  Next, in step 413, the ECU 50 determines whether or not the difference between the target throttle opening degree TTA and the final target throttle opening degree TTAc is equal to or greater than a predetermined value B. If this determination result is negative, the ECU 50 proceeds to step 415 as it is. On the other hand, when this determination result is affirmative, the ECU 50 proceeds to step 414.

  After step 413, in step 415, the ECU 50 controls the electronic throttle device 14 based on the final target throttle opening degree TTAc. That is, when the difference between the target throttle opening degree TTA and the final target throttle opening degree TTAc is smaller than the predetermined value B, the ECU 50 controls the electronic throttle device 14 based on the final target throttle opening degree TTAc obtained in step 412. To control. In this case, the opening of the throttle valve 21 is throttled closer to the closing side than the target throttle opening TTA obtained by referring to the map.

  After step 413, in step 414, the ECU 50 obtains the result of subtracting the predetermined value B from the target throttle opening degree TTA as the final target throttle opening degree TTAc.

  Then, the ECU 50 proceeds to step 415 and controls the electronic throttle device 14 based on the final target throttle opening degree TTAc. That is, if the difference between the target throttle opening degree TTA and the final target throttle opening degree TTAc is equal to or greater than the predetermined value B, the ECU 50 subtracts the predetermined target value B from the target throttle opening degree TTA. The electronic throttle device 14 is controlled based on the final target throttle opening degree TTAc. In this case, the opening of the throttle valve 21 is throttled closer to the closing side than the target throttle opening TTA obtained by referring to the map.

  According to the above control, when the ECU 50 determines that no EGR gas remains in the intake passage 3 upstream of the electronic throttle device 14 (throttle valve 21) during acceleration operation of the engine 1, the EGR valve 18 is The electronic throttle device 14 is controlled to prevent torque reduction of the engine 1 that occurs when EGR gas first reaches the combustion chamber 16 after the valve is opened. Specifically, the ECU 50 controls the electronic throttle device 14 so that the EGR gas reaches the combustion chamber 18 for the first time after the EGR valve 18 is opened, to be closer to the closed side than the predetermined target throttle opening TTA based on the map. After the EGR gas first reaches the combustion chamber 16, the electronic throttle device 14 is controlled to the target throttle opening TTA.

  Here, FIG. 9 shows an example of the behavior of various parameters related to the control in a time chart. In FIG. 9, when the engine 1 is in idling operation, as shown by a thick line in FIG. 9D, when the opening of the throttle valve 21 (throttle opening TA) increases from time t1 to time t3, that is, the engine When 1 accelerates, the intake air amount Ga increases as shown by a thick line in FIG. 5B, the ignition timing is advanced as shown in FIG. 5C, and as shown by a thick line in FIG. The torque of the engine 1 increases. At this time, as shown in FIG. 9 (d), the opening degree of the EGR valve 18 also increases in the same manner as the throttle valve 21. 9 (e), the EGR rate Pegr at the outlet 17a of the EGR passage 17 increases from time t1 to time t3, but as shown in FIG. 9 (f), in the combustion chamber 16 The EGR rate Pegr is delayed from time t2 to time t4. This means that there is a delay until the EGR gas that is led out from the outlet 17a of the EGR passage 17 reaches the combustion chamber 16 when the EGR valve 18 opens. In this embodiment, in consideration of this delay, the opening of the throttle valve 21 increases more gradually from time t3 to time t4, as indicated by a thick line in FIG. 9 (d). Here, from time t1 to time t4, the opening degree of the throttle valve 21 indicated by a thick line in FIG. 9D corresponds to the corrected final target throttle opening degree TTAc, which is the same figure (d). The opening is a closing side opening smaller than the target throttle opening TTA indicated by a two-dot chain line. As a result, the intake air amount Ga stably increases from time t1 to time t4 as shown by a thick line in FIG. 9B, and in the case shown by a two-dot chain line in FIG. 9B (throttle valve 21). Is not rapidly increased or decreased as in the case where the valve is opened at the target throttle opening degree TTA). As a result, the torque of the engine 1 increases steadily as shown by a thick line in FIG. 9A, and in the case shown by a two-dot chain line in FIG. 9A (the throttle valve 21 has a target throttle opening TTA). Torque down does not occur as in the case of valve opening at

  According to the supercharged engine control apparatus in this embodiment described above, the inlet 17b of the EGR passage 17 is connected to the exhaust passage 5 downstream of the turbine 9, and the outlet 17a of the EGR passage 17 is upstream of the compressor 8. Since it is connected to the intake passage 3, the path of the intake passage 3 from the outlet 17a of the EGR passage 17 to the electronic throttle device 14 (throttle valve 21) is relatively long. Further, when the engine 1 is accelerating or steady, the EGR valve 18 is controlled to open by the ECU 50 based on the operating state of the engine 1, and when the engine 1 is stopped or decelerated, the EGR valve 18 is controlled to be closed by the ECU 50. Is done. For this reason, when the EGR gas does not remain in the intake passage 3 upstream from the throttle valve 21 during the acceleration operation of the engine 1, the throttle valve 21 is opened, and the EGR valve 18 is controlled to open. There will be a delay before the combustion chamber 16 is first reached. When the EGR gas first reaches the combustion chamber 16, the EGR rate Pegr in the combustion chamber 16 becomes excessive, resulting in a torque down in the engine 1 and a step in the torque of the engine 1.

  Therefore, in this embodiment, when the ECU 50 determines that EGR gas does not remain in the intake passage 3 upstream of the throttle valve 21 during acceleration operation of the engine 1, the EGR valve 18 is opened. When the EGR gas first reaches the combustion chamber 16, the electronic throttle device 14 is controlled by the ECU 50 in order to prevent the torque of the engine 1 from being reduced. Specifically, after the EGR valve 18 is opened, until the EGR gas reaches the combustion chamber 18 for the first time, the ECU 50 controls the electronic throttle device 14 closer to the closing side than the normal target throttle opening TTA, and the EGR gas is combusted. After reaching the chamber 16 for the first time, the electronic throttle device 14 is controlled by the ECU 50 to the normal target throttle opening TTA. Therefore, during the acceleration operation of the engine 1, the intake air amount Ga supplied to the combustion chamber 16 until EGR gas newly flows from the EGR passage 17 to the intake passage 3 and reaches the combustion chamber 16 for the first time is reduced. By suppressing the combustion of the air-fuel mixture, the torque reduction of the engine 1 when the EGR gas first reaches the combustion chamber 16 is suppressed. As a result, when the engine 1 starts the acceleration operation from the state where no EGR gas remains in the intake passage 3 and restarts the EGR, a torque step occurs in the engine 1 due to the arrival delay of the EGR gas to the combustion chamber 16. This can be prevented beforehand.

Second Embodiment
Next, a second embodiment in which the control device for an engine with a supercharger according to the present invention is embodied will be described in detail with reference to the drawings.

  In each embodiment described below, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different points are mainly described.

  This embodiment differs from the first embodiment in the processing contents of EGR control and throttle control. FIG. 10 is a flowchart showing an example of the processing contents of the throttle control in this embodiment. The flowchart of FIG. 10 is the same as the flowchart of FIG. 7 in terms of the processing contents of Step 400 to Step 407, Step 409 to Step 411, Step 415, and Step 416, and the processing contents of Step 420 to Step 424 are similar to those in FIG. This is different from the flowchart of FIG.

In this embodiment, the ECU 50 obtains the throttle opening correction coefficient Kegr2 corresponding to the EGR rate Pegr1 in step 420 through the processing of steps 401 to 407.
The ECU 50 can obtain the throttle opening correction coefficient Kegr2 by referring to the map shown in FIG. This map is set so that when the EGR rate Pegr1 becomes higher than a predetermined value, the throttle opening correction coefficient Kegr2 gradually increases from “1.0”.

  Thereafter, after the processing of step 409 and step 410, in step 421, it is determined whether or not the EGR gas non-containing intake air amount gaegrin (i) is larger than a predetermined value A1. If the determination result is affirmative, the ECU 50 proceeds to step 416 on the assumption that EGR gas has not passed through the throttle valve 21 first and has not reached the combustion chamber 16, and the step as described above is performed. The processing of 416 and step 415 is executed. In this case, the throttle control by the electronic throttle device 14 is controlled to the target throttle opening degree TTA obtained by referring to the map. On the other hand, if this determination result is negative, the ECU 50 proceeds to step 422 assuming that EGR gas first passes through the throttle valve 21 and reaches the combustion chamber 16.

  In step 422, the ECU 50 corrects the target throttle opening degree TTA by the throttle opening degree correction coefficient Kegr2. That is, the ECU 50 obtains the final target throttle TTAc by multiplying the target throttle opening degree TTA by the throttle opening degree correction coefficient Kegr2.

  Next, in step 423, the ECU 50 determines whether or not the difference between the final target throttle opening degree TTAc and the target throttle opening degree TTA is equal to or greater than a predetermined value B. If this determination result is affirmative, the ECU 50 proceeds to step 415 as it is. On the other hand, when this determination result is negative, the ECU 50 shifts the process to step 424.

  After step 423, in step 415, the ECU 50 controls the electronic throttle device 14 based on the final target throttle opening degree TTAc. That is, when the difference between the final target throttle opening degree TTAc and the target throttle opening degree TTA is equal to or larger than the predetermined value B, the ECU 50 controls the electronic throttle device 14 based on the final target throttle opening degree TTAc obtained in step 422. To control. In this case, the opening degree of the throttle valve 21 is opened to the opening side with respect to the target throttle opening degree TTA obtained by referring to the map.

  After step 423, in step 424, the ECU 50 obtains the result of adding the predetermined value B to the target throttle opening TTA as the final target throttle opening TTAc.

  Then, the ECU 50 proceeds to step 415 and controls the electronic throttle device 14 based on the final target throttle opening degree TTAc. That is, when the difference between the final target throttle opening degree TTAc and the target throttle opening degree TTA is smaller than the predetermined value B, the ECU 50 sets a value obtained by adding the predetermined value B to the target throttle opening degree TTA as the final target throttle opening degree TTAc. The electronic throttle device 14 is controlled based on the final target throttle opening degree TTAc. In this case, the opening degree of the throttle valve 21 is opened to the opening side with respect to the target throttle opening degree TTA obtained by referring to the map.

  According to the above control, the ECU 50 controls the electronic throttle device 14 to the predetermined target throttle opening TTA until the EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened, and the EGR gas is burned. After reaching the chamber 16 for the first time, the electronic throttle device 14 is controlled to open more than the target throttle opening degree TTA.

  According to the engine control apparatus with a supercharger in this embodiment described above, the ECU 50 determines that no EGR gas remains in the intake passage 3 upstream of the throttle valve 21 during the acceleration operation of the engine 1. Unlike the first embodiment, the electronic throttle device 14 is controlled to the normal target throttle opening TTA by the ECU 50 until the EGR gas reaches the combustion chamber 16 for the first time after the EGR valve 18 is opened. After the gas reaches the combustion chamber 16 for the first time, the electronic throttle device 14 is controlled by the ECU 50 so that it opens more than the normal target throttle opening TTA. Therefore, the intake air amount Ga supplied to the combustion chamber 16 until the EGR gas reaches the combustion chamber 16 for the first time is reduced more than after the EGR gas first reaches the combustion chamber 16, and the combustion of the air-fuel mixture is performed. Is relatively suppressed, the torque reduction of the engine 1 when the EGR gas first reaches the combustion chamber 16 is suppressed. As a result, when the engine 1 starts the acceleration operation from the state where no EGR gas remains in the intake passage 3 and restarts the EGR, a torque step occurs in the engine 1 due to the arrival delay of the EGR gas to the combustion chamber 16. This can be prevented beforehand.

<Third Embodiment>
Next, a third embodiment that embodies the control device for an engine with a supercharger according to the present invention will be described in detail with reference to the drawings.

  This embodiment is different from the above embodiments in terms of processing contents for adjusting the output of the engine 1 when EGR gas does not remain in the intake passage 3 upstream of the throttle valve 21 during acceleration operation of the engine 1. The configuration is different. FIG. 12 is a flowchart showing an example of processing contents for output adjustment in this embodiment. In this embodiment, an ignition device composed of a spark plug 29 and an igniter 30 is used as the output adjusting means of the present invention for adjusting the output of the engine 1. The flowchart of FIG. 12 is the same as the flowchart of FIG. 7 in terms of the processing contents of Step 400 to Step 407 and Step 409 to Step 411, and the processing of Step 430 to Step 435, Step 440 to Step 445, Step 450 and Step 451 is the same. The content differs from the flowchart of FIG.

In this embodiment, after the processing of step 401 to step 407 and in step 430, the ECU 50 causes the engine speed NE, the engine load KL, the coolant temperature THW, and the EG.
A target ignition timing AOP corresponding to the R rate Pegr1 is obtained. The ECU 50 sets the target ignition timing A
The OP can be obtained by referring to a predetermined map.

  Thereafter, through the processing of step 409 to step 411, in step 431, the ECU 50 obtains a retardation correction coefficient Kegraop corresponding to the EGR rate Pegr1. The ECU 50 can obtain the retardation correction coefficient Kegraop by referring to a map as shown in FIG. This map is set so that when the EGR rate Pegr1 becomes higher than a predetermined value, the retardation correction coefficient Kegraop gradually decreases from “1.0”.

  Next, at step 432, the ECU 50 obtains a final target ignition timing AOPc. That is, the ECU 50 obtains the final target ignition timing AOPc after the retardation correction by multiplying the target ignition timing AOP by the retardation correction coefficient Kegraop.

  Next, in step 433, the ECU 50 determines whether or not the difference between the target ignition timing AOP and the final target ignition timing AOPc is equal to or greater than a predetermined value B1. If this determination result is negative, the ECU 50 proceeds to step 435 as it is. On the other hand, if the determination result is affirmative, the ECU 50 proceeds to step 434.

  After step 433, in step 435, the ECU 50 controls the igniter 30 and the spark plug 29, which are ignition devices, based on the final target ignition timing AOPc. That is, when the difference between the target ignition timing AOP and the final target ignition timing AOPc is smaller than the predetermined value B1, the ECU 50 controls the ignition device based on the final target ignition timing AOPc obtained in step 432. . In this case, the ignition timing by the ignition device is controlled to be retarded from the target ignition timing AOP obtained by referring to the map.

  After step 433, in step 434, the ECU 50 obtains the result of subtracting the predetermined value D from the target ignition timing AOP as the final target ignition timing AOPc.

  Then, the ECU 50 proceeds to step 435 and controls the ignition device based on the final target ignition timing AOPc. That is, when the difference between the target ignition timing AOP and the final target ignition timing AOPc is equal to or greater than the predetermined value B1, the ECU 50 sets the value obtained by subtracting the predetermined value D from the target ignition timing AOP as the final target ignition timing AOPc. The ignition device is controlled based on the target ignition timing AOPc. In this case, the ignition timing by the ignition device is controlled to be retarded from the target ignition timing AOP obtained by referring to the map.

  On the other hand, if the determination result in step 411 is affirmative, the ECU 50 proceeds to step 445 on the assumption that EGR gas has first passed through the throttle valve 21 and reached the combustion chamber 16. In step 445, the ECU 50 sets the target ignition timing AOP obtained in step 430 as the final target ignition timing AOPc. In step 435, the ECU 50 controls the ignition device based on the final target ignition timing AOPc. Therefore, in this case, the ignition timing by the ignition device is controlled to the normal ignition timing set by the map.

  On the other hand, if the determination result in step 402 is negative, that is, if EGR gas remains in the intake passage 3 upstream of the throttle valve 21 after the engine 1 is decelerated, the ECU 50 proceeds to step 440. In step 440, the ECU 50 takes in the engine rotational speed NE, the engine load KL, the throttle opening degree TA, and the coolant temperature THW.

  Next, in step 441, the ECU 50 obtains the target opening degree Tegr of the EGR valve 18 according to the engine rotational speed NE, the engine load KL, the coolant temperature THW, and the like. The ECU 50 can obtain the target opening degree Tegr by referring to a predetermined map.

  Next, at step 442, the ECU 50 controls the EGR valve 18 to open based on the target opening degree Tegr.

  Next, at step 443, the ECU 50 obtains an EGR rate Pegr1. The ECU 50 can obtain the EGR rate Pegr1 from the values of the engine speed NE and the intake pressure PM.

  Next, at step 444, the ECU 50 obtains a target ignition timing AOP according to the engine speed NE, the engine load KL, the coolant temperature THW, and the EGR rate Pegr1. The ECU 50 can obtain the target ignition timing AOP by referring to a predetermined map.

  Thereafter, in step 445, the ECU 50 sets the target ignition timing AOP obtained in step 444 as the final target ignition timing AOPc. In step 435, the ECU 50 controls the ignition device based on the final target ignition timing AOPc. Therefore, in this case, the ignition timing by the ignition device is controlled to the normal ignition timing set by the map.

  On the other hand, if the determination result in step 403 is negative, that is, if the EGR on condition is not satisfied, the ECU 50 proceeds to step 450. In step 450, the ECU 50 takes in the engine rotational speed NE, the engine load KL, and the throttle opening degree TA.

  Next, in step 451, the ECU 50 obtains a target ignition timing AOP according to the engine speed NE, the engine load KL, and the throttle opening degree TA. The ECU 50 can obtain the target ignition timing AOP by referring to a predetermined map.

  Thereafter, in step 445, the ECU 50 sets the target ignition timing AOP obtained in step 451 as the final target ignition timing AOPc. In step 435, the ECU 50 controls the ignition device based on the final target ignition timing AOPc. Therefore, in this case, the ignition timing by the ignition device is controlled to the normal ignition timing set by the map.

  According to the above control, the ECU 50 controls the ignition timing by the ignition device to be retarded from the predetermined target ignition timing AOP until the EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened. After the EGR gas first reaches the combustion chamber 16, the ignition timing by the ignition device is controlled to the target ignition timing AOP obtained by referring to the map.

  Here, FIG. 14 shows an example of the behavior of various parameters related to the above control in a time chart. In FIG. 14, when the engine 1 is in idling operation, as shown by a thick line in FIG. 14D, when the opening of the throttle valve 21 (throttle opening TA) increases from time t1 to time t3, that is, the engine When 1 accelerates, the opening degree of the EGR valve 18 also increases in the same manner as the throttle valve 21 as indicated by a broken line in FIG. Accordingly, as shown by a thick line in FIG. 14B, the intake air amount Ga suddenly increases between time t1 and time t4. As can be seen from the behavior of the EGR rate Pegr shown in FIGS. 14E and 14F, the intake air amount Ga includes EGR gas that reaches the combustion chamber 16 after the EGR valve 18 is opened. It is. In this embodiment, in consideration of the delay in arrival of the EGR gas, the ignition timing by the ignition device is controlled in two stages from time t1 to time t4 to be retarded as shown by a thick line in FIG. Has been. Here, the ignition timing indicated by the thick line in FIG. 14C corresponds to the final target ignition timing AOPc after the retardation correction, and is retarded from the target ignition timing AOP indicated by the two-dot chain line in FIG. Is set to Thereby, from time t1 to time t4, the torque of the engine 1 stably increases as shown by a thick line in FIG. 14A, and when indicated by a two-dot chain line in FIG. As in the case of control by the ignition timing AOP, there is no sudden increase / decrease in torque step.

  According to the engine control device with a supercharger in this embodiment described above, unlike the above embodiments, the ignition device until EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened. The ignition timing by the ECU 50 is controlled to be retarded from the normal target ignition timing AOP, and after the EGR gas first reaches the combustion chamber 16, the ignition timing by the ignition device is controlled by the ECU 50 to the normal target ignition timing AOP. Is done. Therefore, the ignition timing of the air-fuel mixture in the combustion chamber 16 is retarded until EGR gas reaches the combustion chamber 16 for the first time, and the combustion of the air-fuel mixture is suppressed, so that the EGR gas first enters the combustion chamber 16. Torque down of the engine 1 when it reaches is suppressed. As a result, when the engine 1 starts the acceleration operation from the state where no EGR gas remains in the intake passage 3 and restarts the EGR, a torque step occurs in the engine 1 due to the arrival delay of the EGR gas to the combustion chamber 16. This can be prevented beforehand.

<Fourth embodiment>
Next, a fourth embodiment that embodies a control device for an engine with a supercharger according to the present invention will be described in detail with reference to the drawings.

  FIG. 15 is a schematic configuration diagram showing an engine system including an exhaust gas recirculation device (EGR device) for an engine with a supercharger in this embodiment. This embodiment is different from the engine system shown in FIG. 1 in the following points. That is, in this embodiment, a fresh air introduction passage 41 for introducing fresh air to the surge tank 3a downstream from the electronic throttle device 14 (throttle valve 21) is provided. The fresh air introduction passage 41 has an inlet 41 a downstream of the air cleaner 6 and connected to the intake passage 3 upstream of the outlet 17 a of the EGR passage 17, and an outlet 41 b connected to the intake passage 3 downstream of the throttle valve 21. Is done. In the middle of the fresh air introduction passage 41, an electric fresh air control valve 42 is provided. The fresh air control valve 42 is configured to control the opening degree of the valve body with respect to the valve seat by driving the valve body with a solenoid. By controlling the opening degree of the fresh air control valve 42, the flow rate of fresh air introduced from the fresh air introduction passage 41 to the surge tank 3a is controlled.

  This embodiment is different from the above embodiments in terms of processing contents for adjusting the output of the engine 1 when EGR gas does not remain in the intake passage 3 upstream of the throttle valve 21 during acceleration operation of the engine 1. The configuration is different. FIG. 16 is a flowchart showing an example of processing contents for output adjustment in this embodiment. In this embodiment, the fresh air introduction device constituted by the fresh air introduction passage 41 and the fresh air control valve 42 is used as the output adjusting means of the present invention for adjusting the output of the engine 1. The flowchart of FIG. 16 is the same as the flowchart of FIG. 12 in terms of the processing contents of Step 400 to Step 407 and Step 409 to Step 411, Step 440 to Step 443, and Step 450, and Step 460 to Step 465, Step 470, Step The processing contents of 471 and step 480 differ from the flowchart of FIG.

In this embodiment, after the processing of step 401 to step 407 and in step 460, the ECU 50 causes the engine speed NE, the engine load KL, the coolant temperature THW, and the EG.
A target opening iscstp of the fresh air control valve 42 corresponding to the R rate Pegr1 is obtained. The ECU 50 can obtain the target opening iscstp by referring to a predetermined map.

  Thereafter, through the processing of step 409 to step 411, in step 461, the ECU 50 obtains a fresh air correction coefficient Kegrisc corresponding to the EGR rate Pegr1. The ECU 50 can obtain the fresh air correction coefficient Kegrisc by referring to a map as shown in FIG. This map is set so that the fresh air correction coefficient Kegrisc gradually decreases from “1.0” when the EGR rate Pegr1 becomes higher than a predetermined value.

  Next, in step 462, the ECU 50 obtains the final target opening degree ISCstp. That is, the ECU 50 obtains the corrected final target opening degree ISCstp by multiplying the target opening degree iscstp by the fresh air correction coefficient Kegrisc.

  Next, at step 463, the ECU 50 determines whether or not the difference between the target opening iscstp and the final target opening ISCstp is equal to or greater than a predetermined value F. If this determination result is negative, the ECU 50 proceeds to step 465 as it is. On the other hand, when this determination result is affirmative, the ECU 50 proceeds to step 464.

  In step 465 after shifting from step 463, the ECU 50 controls the fresh air control valve 42 based on the final target opening ISCstp. That is, when the difference between the target opening iscstp and the final target opening ISCstp is smaller than the predetermined value F, the ECU 50 opens the fresh air control valve 42 based on the final target opening ISCstp obtained in step 462. To control. In this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled to be smaller than that at the target opening iscstp obtained by referring to the map.

  After step 463, in step 464, the ECU 50 obtains the final target opening degree ISCstp as a result of subtracting the predetermined value F from the target opening degree iscstp.

  Then, the ECU 50 proceeds to step 465 and controls the fresh air control valve 42 based on the final target opening degree ISCstp. That is, when the difference between the target opening iscstp and the final target opening ISCstp is equal to or larger than the predetermined value F, the ECU 50 sets the value obtained by subtracting the predetermined value F from the target opening iscstp as the final target opening ISCstp. The fresh air control valve 42 is controlled to open based on the target opening degree ISCstp. In this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled to be smaller than that at the target opening iscstp obtained by referring to the map.

  On the other hand, if the determination result in step 411 is affirmative, the ECU 50 proceeds to step 471 on the assumption that EGR gas first passed through the throttle valve 21 and reached the combustion chamber 16. In step 471, the ECU 50 sets the target opening iscstp obtained in step 460 as the final target opening ISCstp. In step 465, the ECU 50 controls the fresh air control valve 42 based on the final target opening ISCstp. Therefore, in this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled to the normal fresh air introduction amount set by the map.

On the other hand, if the determination result in step 402 is negative, that is, if EGR gas remains in the intake passage 3 upstream of the throttle valve 21 after the engine 1 is decelerated, the ECU 50 performs the processing in steps 440 to 443. In step 470, the target opening according to the engine speed NE, the engine load KL, the coolant temperature THW, and the EGR rate Pegr1
Ask for iscstp. The ECU 50 can obtain the target opening iscstp by referring to a predetermined map.

  Thereafter, in step 471, the ECU 50 sets the target opening degree iscstp obtained in step 470 as the final target opening degree ISCstp. In step 465, the ECU 50 controls the fresh air control valve 42 based on the final target opening degree ISCstp. Accordingly, in this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled to the normal amount of fresh air introduced by the map.

  On the other hand, when the determination result of step 403 is negative, that is, when the EGR on condition is not satisfied, the ECU 50 executes the process of step 450 and then at step 480, the engine speed NE, the engine load KL, and A target opening iscstp corresponding to the throttle opening TA is obtained. The ECU 50 can obtain the target opening iscstp by referring to a predetermined map.

  Thereafter, in step 471, the ECU 50 sets the target opening iscstp obtained in step 480 as the final target opening ISCstp, and in step 465 controls the fresh air control valve 42 based on the final target opening ISCstp. Accordingly, in this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled to the normal amount of fresh air introduced by the map.

  According to the above control, the ECU 50 causes the fresh air control valve 42 to introduce fresh air into the surge tank 3a until the EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened. After the EGR gas reaches the combustion chamber 16 for the first time, the introduction of fresh air into the surge tank 3a by the fresh air control valve 42 is changed to the usual target opening iscstp. It is increased to the corresponding normal target amount.

  According to the control device for an engine with a supercharger in this embodiment described above, unlike the above-described embodiments, the fresh air until the EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened. The introduction of fresh air by the control valve 42 is reduced by the ECU 50 from the normal target amount corresponding to the normal target opening iscstp, and after the EGR gas first reaches the combustion chamber 16, the fresh air by the fresh air control valve 42 is obtained. Is increased by the ECU 50 to a normal target amount corresponding to the normal target opening iscstp. Therefore, the total amount of intake air and fresh air supplied to the combustion chamber 16 until the EGR gas reaches the combustion chamber 16 for the first time is reduced, and the combustion of the air-fuel mixture is suppressed. The torque reduction of the engine 1 when it first reaches is suppressed. As a result, when the engine 1 starts the acceleration operation from the state where no EGR gas remains in the intake passage 3 and restarts the EGR, a torque step occurs in the engine 1 due to the arrival delay of the EGR gas to the combustion chamber 16. This can be prevented beforehand.

<Fifth Embodiment>
Next, a fifth embodiment that embodies the control device for an engine with a supercharger according to the present invention will be described in detail with reference to the drawings.

  In the present embodiment, the fourth embodiment is described in terms of processing contents for adjusting the output of the engine 1 when the EGR gas does not remain in the intake passage 3 upstream of the throttle valve 21 during the acceleration operation of the engine 1. And the configuration is different. FIG. 18 is a flowchart showing an example of the processing content. 18 differs from the processing contents of steps 411 and 461 to 464 in the flowchart of FIG. 16 in the processing contents of steps 490 to 494.

  In this embodiment, the ECU 50 determines whether or not the EGR gas non-containing intake air amount gaegrin (i) is larger than the predetermined value A1 through the processing of step 401 to step 407, step 460, step 409 and step 410 in step 490. Determine whether. If this determination result is affirmative, the ECU 50 proceeds to step 471 on the assumption that EGR gas has not first passed through the throttle valve 21 and reached the combustion chamber 16, and the processing of step 471 and step 465 is performed. Execute. In this case, the introduction of fresh air by the fresh air control valve 42 is controlled to a normal target amount corresponding to the normal target opening iscstp obtained by referring to the map. On the other hand, if this determination result is negative, the ECU 50 proceeds to step 491 on the assumption that EGR gas has first passed through the throttle valve 21 and reached the combustion chamber 16.

  In step 491, the ECU 50 obtains a fresh air correction coefficient Kegrisc2 corresponding to the EGR rate Pegr1. The ECU 50 can obtain the fresh air correction coefficient Kegrisc2 by referring to a map as shown in FIG. This map is set so that the fresh air correction coefficient Kegrisc gradually increases from “1.0” when the EGR rate Pegr1 becomes higher than a predetermined value.

  Next, in step 492, the ECU 50 obtains the final target opening degree ISCstp. In other words, the ECU 50 obtains the corrected final target opening ISCstp by multiplying the target opening iscstp by the fresh air correction coefficient Kegrisc2.

  Next, in step 493, the ECU 50 determines whether or not the difference between the final target opening degree ISCstp and the target opening degree iscstp is equal to or greater than a predetermined value F. If this determination result is negative, the ECU 50 proceeds to step 465 as it is. On the other hand, if the determination result is affirmative, the ECU 50 proceeds to step 494.

  After step 493, in step 465, the ECU 50 controls the fresh air control valve 42 based on the final target opening degree ISCstp. That is, when the difference between the final target opening ISCstp and the target opening iscstp is smaller than the predetermined value F, the ECU 50 opens the fresh air control valve 42 based on the final target opening ISCstp obtained in step 492. To control. In this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled more frequently than when the normal target opening iscstp is obtained by referring to the map.

  After step 493, in step 494, the ECU 50 obtains the result of adding the predetermined value F to the target opening iscstp as the final target opening ISCstp.

  Then, the ECU 50 proceeds to step 465 and controls the fresh air control valve 42 based on the final target opening degree ISCstp. That is, when the difference between the final target opening ISCstp and the target opening iscstp is equal to or larger than the predetermined value F, the ECU 50 sets the value obtained by adding the predetermined value F to the target opening iscstp as the final target opening ISCstp. The fresh air control valve 42 is controlled to open based on the target opening degree ISCstp. In this case, the amount of fresh air introduced into the surge tank 3a by the fresh air control valve 42 is controlled more frequently than when the normal target opening iscstp is obtained by referring to the map.

  According to the above control, the ECU 50 causes the fresh air control valve 42 to introduce fresh air into the surge tank 3a until the EGR gas first reaches the combustion chamber 16 after the EGR valve 18 is opened. The normal target amount corresponding to the degree iscstp is controlled, and after the EGR gas reaches the combustion chamber 16 for the first time, the introduction of fresh air into the surge tank 3a by the fresh air control valve 42 corresponds to the usual target opening iscstp. The normal target amount is increased.

  According to the control apparatus for an engine with a supercharger of this embodiment described above, unlike the above-described embodiments, the fresh air until the EGR gas reaches the combustion chamber 16 for the first time after the EGR valve 18 is opened. The introduction of fresh air by the control valve 42 is controlled by the ECU 50 to a normal target amount corresponding to the normal target opening iscstp, and after the EGR gas first reaches the combustion chamber 16, fresh air is introduced by the fresh air control valve 42. The introduction is increased by the ECU 50 beyond the normal target amount corresponding to the normal target opening iscstp. Therefore, the total amount of intake air and fresh air supplied to the combustion chamber 16 until EGR gas reaches the combustion chamber 16 for the first time is reduced more than after the EGR gas reaches the combustion chamber 16 for the first time. By suppressing the combustion of the gas relatively, the torque reduction of the engine 1 when the EGR gas first reaches the combustion chamber 16 is suppressed. As a result, when the engine 1 starts the acceleration operation from the state where no EGR gas remains in the intake passage 3 and restarts the EGR, a torque step occurs in the engine 1 due to the arrival delay of the EGR gas to the combustion chamber 16. This can be prevented beforehand.

  The present invention is not limited to the above-described embodiments, and a part of the configuration can be changed as appropriate without departing from the spirit of the invention.

  For example, in the third embodiment, an ignition device is used as the output adjusting means so that no torque step is generated in the engine 1, and in the fourth and fifth embodiments, a fresh air introducing device is used as the output adjusting means. It was used so that a torque step would not occur in the engine 1. On the other hand, it is possible to use both the ignition device and the fresh air introduction device as the output adjusting means so that no torque step is generated in the engine.

  The present invention can be used for an automobile engine regardless of, for example, a gasoline engine or a diesel engine.

DESCRIPTION OF SYMBOLS 1 Engine 3 Intake passage 3a Surge tank 5 Exhaust passage 7 Supercharger 8 Compressor 9 Turbine 10 Rotating shaft 14 Electronic throttle device (intake air amount adjustment valve, output adjustment means)
16 Combustion chamber 17 EGR passage (exhaust gas recirculation passage)
17a outlet 17b inlet 18 EGR valve (exhaust gas recirculation valve)
21 Throttle valve 23 Throttle sensor (operating state detection means)
27 Accelerator sensor (operating state detection means)
29 Spark plug (ignition device, output adjustment means)
30 igniter (ignition device, output adjustment means)
41 Fresh air introduction passage (fresh air introduction device, output adjustment means)
42 Fresh air control valve (fresh air introduction device, output adjustment means)
50 ECU (control means)
51 Intake pressure sensor (operating state detection means)
52 Rotational speed sensor (Operating state detection means)
53 Water temperature sensor (Operating state detection means)

Claims (6)

A turbocharger provided between an intake passage and an exhaust passage of the engine for boosting intake air in the intake passage;
The supercharger includes a compressor disposed in the intake passage, a turbine disposed in the exhaust passage, and a rotation shaft that connects the compressor and the turbine so as to be integrally rotatable.
An intake air amount adjustment valve provided in the intake passage downstream of the compressor, for adjusting the intake air amount in the intake passage;
A part of the exhaust discharged from the combustion chamber of the engine to the exhaust passage is made to flow as an exhaust recirculation gas to the intake passage and is recirculated to the combustion chamber, and the exhaust recirculation gas in the exhaust recirculation passage is adjusted. An exhaust gas recirculation device including an exhaust gas recirculation valve for,
The exhaust gas recirculation passage has an inlet connected to the exhaust passage downstream from the turbine, and an outlet connected to the intake air passage upstream from the intake air amount adjustment valve and the compressor ;
An output adjusting means for adjusting the output of the previous SL engine,
An operating state detecting means for detecting the operating state of the engine;
Control means for controlling the exhaust gas recirculation valve based on the detected operating state and controlling the output adjusting means;
The control means controls to open the exhaust gas recirculation valve based on the detected operating state during acceleration operation or steady operation of the engine, and closes the exhaust gas recirculation valve when the engine is stopped or decelerated. To do
In the control device for an engine with a supercharger, the intake air amount adjustment valve is opened during acceleration operation or steady operation of the engine, and is closed when the engine is stopped or decelerated.
When the control means determines that the exhaust gas recirculation gas does not remain in the intake passage upstream of the intake air amount adjustment valve during acceleration operation of the engine, the control means opens the exhaust gas recirculation valve. The output adjusting means is controlled to prevent the engine torque reduction that occurs when the exhaust gas recirculation gas first reaches the combustion chamber, and is upstream of the intake air amount adjustment valve during the acceleration operation of the engine. When the exhaust gas recirculation gas is determined to remain in the intake passage, the opening of the exhaust gas recirculation valve from the closed state is delayed until the remaining exhaust gas recirculation gas decreases to a predetermined value or less. A control device for a supercharged engine.   The output adjustment means is the intake air amount adjustment valve, and the control means controls the intake air amount adjustment valve until the exhaust gas recirculation gas first reaches the combustion chamber after the exhaust gas recirculation valve opens. 2. The control according to claim 1, wherein the valve is controlled to be closer than a predetermined target opening, and the intake air amount adjustment valve is controlled to the target opening after the exhaust gas recirculation gas first reaches the combustion chamber. The supercharger-equipped engine control device described.   The output adjustment means is the intake air amount adjustment valve, and the control means controls the intake air amount adjustment valve until the exhaust gas recirculation gas first reaches the combustion chamber after the exhaust gas recirculation valve opens. 2. The control according to claim 1, wherein the control is performed to a predetermined target opening degree, and after the exhaust gas recirculation gas reaches the combustion chamber for the first time, the intake air amount adjustment valve is controlled to open more than the target opening degree. The supercharger-equipped engine control device described.   The output adjusting means is an ignition device for igniting the air-fuel mixture sucked into the combustion chamber, and the control means first causes the exhaust recirculation gas to enter the combustion chamber after the exhaust recirculation valve is opened. The ignition timing by the ignition device is controlled to be retarded from a predetermined target ignition timing until it reaches, and after the exhaust gas recirculation gas first reaches the combustion chamber, the ignition timing by the ignition device is set to the target ignition timing. The control device for an engine with a supercharger according to claim 1, wherein   The output adjusting means is a fresh air introducing device for introducing fresh air into the intake passage downstream of the intake air amount adjusting valve, and the control means is configured to release the exhaust recirculation gas after the exhaust recirculation valve is opened. Until the first arrival at the combustion chamber, the introduction of the fresh air by the fresh air introduction device is reduced below a predetermined target amount, and after the exhaust gas recirculation gas first reaches the combustion chamber, the introduction of the fresh air The supercharged engine control device according to claim 1, wherein the introduction of the fresh air by the device is increased to the target amount.   The output adjusting means is a fresh air introducing device for introducing fresh air into the intake passage downstream of the intake air amount adjusting valve, and the control means is configured to release the exhaust recirculation gas after the exhaust recirculation valve is opened. Until the first reaches the combustion chamber, the introduction of the fresh air by the fresh air introduction device is controlled to a predetermined target amount, and after the exhaust gas recirculation gas first reaches the combustion chamber, the fresh air introduction device The supercharged engine control device according to claim 1, wherein the introduction of the fresh air by the engine is increased more than the target amount.

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