JP6179241B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device including a supercharging system that uses exhaust pressure.

  Conventionally, in an engine equipped with a supercharging system that uses the exhaust pressure of the engine, an electric waste gate valve (open / close valve) is provided in a bypass for bypassing a turbocharging turbine interposed in the exhaust passage. There is something. The waste gate valve is a supercharging pressure control valve that adjusts the supercharging state (supercharging pressure), and is controlled by the electric actuator so that the flow rate of exhaust gas flowing into the supercharging turbine is controlled. The rotational speed of the turbine is controlled.

  For example, when the output demand for the engine is high, such as during acceleration, the rotational speed of the supercharging turbine increases by reducing or closing (closing) the opening of the waste gate valve. Accordingly, the amount of intake air to be supercharged is increased and the supercharging efficiency is improved, so that a high output can be obtained. On the other hand, when the output demand for the engine is low, such as during deceleration, the rotational speed of the supercharging turbine decreases by increasing or opening (opening) the wastegate valve. As a result, the amount of intake air that is supercharged is reduced, and the amount of intake air commensurate with the output is sent.

  In this way, by controlling the opening degree of the waste gate valve according to the required output, it is possible to control the amount of intake air that is supercharged (that is, the supercharging pressure). In other words, in order to accurately control the supercharging pressure, it is necessary to accurately control the opening degree of the waste gate valve.

  However, since the waste gate valve is exposed to the exhaust gas, carbon contained in the exhaust gas may adhere to the waste gate valve. If the attached carbon adheres and becomes a deposit, it may cause a malfunction of the waste gate valve. Therefore, a technique for cleaning a valve interposed in an exhaust passage or the like has been proposed.

  For example, Patent Document 1 discloses a technique for removing deposits such as carbon adhering to a bypass valve provided in an exhaust passage. In this technique, the operation control unit that controls the stop of the engine is configured to stop the engine after a predetermined time has elapsed after receiving the stop instruction. ) Can open and close the bypass valve to remove deposits from the bypass valve.

Japanese Patent No. 2007-211173

  However, in the apparatus of Patent Document 1 described above, the bypass valve is opened and closed during a predetermined time from when the engine stop instruction is received until the engine is completely stopped. It is difficult to secure. In this device, since the engine stops and the exhaust flow stops after opening and closing the valve, there is a possibility that deposits that have come off the valve accumulate in the exhaust passage.

  In particular, in the case of an engine equipped with an in-cylinder injection valve that directly injects fuel into the cylinder, there is a high possibility that carbon will be generated. It is desirable to prevent it. In particular, if deposits accumulate on the waste gate valve that adjusts the supercharging pressure, the supercharging pressure control is affected. Therefore, it is necessary to reliably remove the deposits adhering to the waste gate valve.

  The present invention has been devised in view of such a problem, and an object thereof is to provide an engine control device capable of preventing carbon from being deposited on a waste gate valve. The present invention is not limited to this purpose, and is a function and effect derived from each configuration shown in the embodiments for carrying out the invention described later, and other effects of the present invention are to obtain a function and effect that cannot be obtained by conventional techniques. Can be positioned.

(1) An engine control device disclosed herein is an engine control device including a waste gate valve that is interposed in a bypass route that bypasses a turbocharging turbine on an exhaust passage and is driven by an electric actuator. A determination unit that determines whether or not a predetermined cleaning start condition is satisfied, and a cleaning that performs cleaning by opening and closing the waste gate valve when the determination unit determines that the cleaning start condition is satisfied Control means. The determination unit determines whether or not a predetermined cleaning permission condition is satisfied, and determines whether or not the cleaning start condition is satisfied when the cleaning permission condition is satisfied. Further , the cleaning start condition includes that the vehicle is traveling at a reduced speed.

(2) It is preferable to provide a fuel cut control means for performing fuel cut control for cutting off fuel supply during operation of the engine. In this case, it is preferable that the cleaning start condition includes that the fuel cut control is being performed by the fuel cut control means .

( 3 ) A detecting means for detecting the position of the waste gate valve, and a zero point of the waste gate valve from the position detected by the detecting means with the waste gate valve fully closed after the engine is started. And learning means for learning. In this case, it is preferable that the cleaning permission condition includes learning of the zero point by the learning unit.

( 4 ) The learning means learns the initial fully closed position of the waste gate valve from the position detected by the detecting means by fully closing the waste gate valve before starting the engine, and permits the cleaning. The condition preferably includes that an absolute value of a difference between the initial fully closed position learned by the learning unit and the zero point is a predetermined value or more.

( 5 ) Further, injection control for controlling in-cylinder injection that is fuel injection into the cylinder of the engine and port injection that is fuel injection into the intake port of the cylinder based on the operating state of the engine. Preferably means are provided. In this case, it is preferable that the cleaning permission condition includes that the in-cylinder injection and the port injection are performed in the same combustion cycle by the injection control unit.

( 6 ) In addition, it is preferable to include a running idle stop control means for automatically stopping the engine during the running of the vehicle when a predetermined running idle stop execution condition is satisfied. In this case, the running idle stop control means may prohibit the automatic stop of the engine if the cleaning by the cleaning control means is not carried out even when the running idle stop execution condition is satisfied. preferable.

According to the disclosed engine control device, carbon deposition on the waste gate valve can be prevented. In addition, since the cleaning start condition is not determined unless the cleaning permission condition is satisfied, the timing for performing cleaning can be appropriately set depending on the setting of the cleaning permission condition.

It is a figure which illustrates the block configuration of the control apparatus of the engine which concerns on one Embodiment, and the structure of the engine to which this control apparatus was applied. It is a figure which illustrates the block configuration of the control apparatus of FIG. It is the example of a map which showed the relation of the valve position to the opening of a waste gate valve. It is a flowchart which illustrates the procedure of the learning control in an engine control apparatus. It is a flowchart which illustrates the procedure of the opening degree control in an engine control apparatus. It is a flowchart which illustrates the procedure of the cleaning control in an engine control apparatus.

  Hereinafter, embodiments will be described with reference to the drawings. Note that the embodiment described below is merely an example, and there is no intention to exclude various modifications and technical applications that are not explicitly described in the following embodiment. Each configuration of the present embodiment can be implemented with various modifications without departing from the spirit of the present embodiment, and can be selected or combined as necessary.

[1. Device configuration]
[1-1. engine]
The engine control device of the present embodiment is applied to the on-vehicle gasoline engine 10 (hereinafter simply referred to as the engine 10) shown in FIG. The engine 10 includes a fuel injection system that uses both port injection and in-cylinder injection, a supercharging system that uses exhaust pressure, and an EGR system (exhaust gas recirculation system). FIG. 1 shows one of a plurality of cylinders (cylinders) provided in a multi-cylinder engine 10. A piston is slidably housed in the cylinder, and the reciprocating motion of the piston is converted into the rotational motion of the crankshaft via the connecting rod.

  An intake port and an exhaust port are provided on the top surface of each cylinder, and an intake valve and an exhaust valve are provided in each port opening. In addition, a spark plug 15 is provided between the intake port and the exhaust port in a state where the tip thereof protrudes toward the combustion chamber. The timing of ignition at the spark plug 15 (ignition timing) is controlled by the engine control device 1 described later.

[1-2. Fuel injection system]
As an injector for supplying fuel to each cylinder, an in-cylinder injection valve (direct injection injector) 11 that directly injects fuel into the cylinder, and a port injection valve (port injection injector) 12 that injects fuel into the intake port, Is provided. Two types of fuel injection modes are used or combined depending on the operating state of the engine 10 to burn the fuel mixture in a state where the concentration distribution of the fuel mixture in the cylinder is uniform, and the high concentration mixture Is stratified combustion, in which combustion is performed in a state of being biased in a layered manner in the vicinity of the spark plug 15.

  Port injection is mainly used during homogeneous combustion, and in-cylinder injection is mainly used during stratified combustion. However, even during fuel injection from the in-cylinder injection valve 11, homogeneous combustion can be realized. In homogeneous combustion by in-cylinder injection, latent heat is absorbed when the fuel evaporates in the cylinder, and the volumetric efficiency tends to increase. In addition, knocking is unlikely to occur because the combustion temperature decreases. The fuel injected from the in-cylinder injection valve 11 is guided, for example, in the vicinity of the spark plug 15 on a layered air flow formed in the cylinder, and is unevenly distributed in the intake air. On the other hand, the fuel injected from the port injection valve 12 is atomized in, for example, the intake port and introduced into the cylinder in a state of being well mixed with the intake air.

  These two types of injection valves 11 and 12 are also provided in other cylinders (not shown) provided in the engine 10. The amount of fuel injected from the cylinder injection valve 11 and the port injection valve 12 and the injection timing thereof are controlled by the engine control device 1. For example, a control pulse signal is transmitted from the engine control device 1 to each of the injection valves 11 and 12, and the injection ports of the injection valves 11 and 12 are opened only during a period corresponding to the magnitude of the control pulse signal. Thereby, the fuel injection amount becomes an amount corresponding to the magnitude (drive pulse width) of the control pulse signal, and the injection start time corresponds to the time when the control pulse signal is transmitted.

  In-cylinder injection valve 11 is connected to high-pressure pump 14A via high-pressure fuel supply path 13A. On the other hand, the port injection valve 12 is connected to a low-pressure pump 14B via a low-pressure fuel supply path 13B. The cylinder injection valve 11 is supplied with fuel having a pressure higher than that of the port injection valve 12. Both the high-pressure pump 14A and the low-pressure pump 14B are mechanical variable flow rate pumps for pumping fuel. These pumps 14A and 14B operate by receiving driving force from the engine 10 or an electric motor, and discharge the fuel in the fuel tank to the supply passages 13A and 13B. The amount of fuel discharged from each pump 14A, 14B and the fuel pressure are controlled by the engine control device 1.

[1-3. Intake and exhaust system]
The upper part of the intake valve is connected to an intake variable valve mechanism 28 for changing the valve lift amount and valve timing, and the upper part of the exhaust valve is connected to an exhaust variable valve mechanism 29. The operations of the intake valve and the exhaust valve are controlled by the engine control device 1 described later via these variable valve mechanisms 28 and 29. Each of the variable valve mechanisms 28 and 29 includes, for example, a variable valve lift mechanism and a variable valve timing mechanism as a mechanism for changing the rocking amount and rocking timing of the rocker arm.

  The variable valve lift mechanism is a mechanism that continuously changes the valve lift amount of each of the intake valve and the exhaust valve. This variable valve lift mechanism has a function of changing the magnitude of swing (valve lift amount) transmitted from the cam fixed to the camshaft to the rocker arm or tappet. The variable valve timing mechanism is a mechanism for changing the opening / closing timing (valve timing) of each of the intake valve and the exhaust valve. This variable valve timing mechanism has a function of changing the rotational phase of the cam or camshaft that causes the rocker arm to swing.

  The intake system 20 and the exhaust system 30 of the engine 10 are provided with a turbocharger (supercharger) 16 that supercharges intake air into the cylinder using exhaust pressure. The turbocharger 16 is interposed across both the intake passage 21 connected to the upstream side of the intake port and the exhaust passage 31 connected to the downstream side of the exhaust port. The turbine (supercharging turbine) 16A of the turbocharger 16 rotates with the exhaust pressure in the exhaust passage 31 and transmits the rotational force to the compressor 16B on the intake passage 21 side. In response to this, the compressor 16B supplies air while compressing the air in the intake passage 21 to the downstream side, and supercharges each cylinder. The supercharging operation by the turbocharger 16 is controlled by the engine control device 1.

  An intercooler 25 is provided on the intake passage 21 downstream of the compressor 16B to cool the compressed air. An air filter 22 is provided on the upstream side of the compressor 16B, and air taken in from the outside is filtered. Further, an intake bypass passage 23 is provided so as to connect the intake passage 21 upstream and downstream of the compressor 16B, and a bypass valve 24 is interposed on the intake bypass passage 23. The amount of air flowing through the intake bypass passage 23 is adjusted according to the opening degree of the bypass valve 24. The bypass valve 24 is controlled, for example, in the opening direction when the vehicle is suddenly decelerated, and functions to release the supercharging pressure supplied from the compressor 16B to the upstream side again. The opening degree of the bypass valve 24 is controlled by the engine control device 1.

  An exhaust gas recirculation (EGR) passage 34 is provided between the downstream side of the compressor 16 </ b> B in the intake system 20 and the upstream side of the turbine 16 </ b> A in the exhaust system 30. The EGR passage 34 is a passage that guides exhaust that has just been exhausted from the cylinder to the upstream side of the cylinder again. An EGR cooler 35 for cooling the reflux gas is interposed in the EGR passage 34. Cooling the reflux gas lowers the combustion temperature in the cylinder and reduces the generation rate of nitrogen oxides (NOx). In addition, an EGR valve 36 for adjusting the exhaust gas recirculation amount is interposed at a junction between the EGR passage 34 and the intake system 20. The valve opening degree of the EGR valve 36 is variable and is controlled by the engine control device 1.

  A throttle body is connected to the downstream side of the intercooler 25, and an intake manifold (intake manifold) is connected to the downstream side thereof. The throttle body is disposed on the upstream side of the junction between the EGR passage 34 and the intake system 20 described above. An electronically controlled throttle valve 26 is provided inside the throttle body. The amount of air flowing to the intake manifold is adjusted according to the opening degree of the throttle valve 26 (throttle opening degree). The throttle opening is controlled by the engine control device 1.

  The intake manifold is provided with a surge tank 27 for temporarily storing the air flowing to each cylinder. The junction between the aforementioned EGR passage 34 and the intake system 20 is located upstream of the surge tank 27. The intake manifold downstream of the surge tank 27 is formed so as to branch toward the intake port of each cylinder, and the surge tank 27 is located at the branch point. The surge tank 27 functions to alleviate intake pulsation and intake interference that can occur in each cylinder.

  A catalyst device 33 is interposed on the exhaust passage 31 downstream of the turbine 16A. This catalyst device 33 purifies, decomposes, and removes components such as PM (Particulate Matter), nitrogen oxide (NOx), carbon monoxide (CO), and hydrocarbon (HC) contained in the exhaust gas, for example. It has a function to do. Further, an exhaust manifold (exhaust manifold) branched toward the exhaust port of each cylinder is connected upstream of the turbine 16A.

  An exhaust bypass passage (bypass) 32 is provided so as to connect the upstream and downstream exhaust passages 31 of the turbine 16 </ b> A, and an electronically controlled waste gate valve 17 is interposed on the exhaust bypass passage 32. The waste gate valve 17 is a supercharging pressure adjustment valve that changes the supercharging pressure by controlling the exhaust flow rate flowing into the turbine 16A side. The waste gate valve 17 is provided with an electric actuator 18. The electric actuator 18 uses electric power such as an auxiliary battery or a drive battery mounted on the vehicle as a drive source, and its operation is controlled by the engine control device 1.

The waste gate valve 17 mechanically connects the valve body 17a that opens and closes the exhaust bypass passage 32, the valve body 17a and the electric actuator 18, and a rod (valve body drive member) 17b that is driven to reciprocate by the electric actuator 18. Have The valve body 17a is connected so as to open and close according to the stroke amount of the rod 17b (the movement length of the rod 17b in the axial direction), and the position S of the valve body 17a (hereinafter referred to as the valve position S) is It is controlled by the engine control device 1. In the valve position S, the position S of the valve body 17a when the waste gate valve 17 is fully closed is set as a reference position S _BA (ie, 0). Stroke of the rod 17b from the reference position S _BA corresponds to the valve opening D of the waste gate valve 17. That is, the valve opening degree D is electrically controlled by the engine control device 1.

[1-4. Detection system]
An accelerator position sensor 41 that detects the amount of depression of the accelerator pedal (accelerator opening APS) is provided at an arbitrary position of the vehicle. The accelerator opening APS is a parameter corresponding to the driver's acceleration request and intention to start, in other words, a parameter correlated to the load of the engine 10 (output request to the engine 10).

  An air flow sensor 42 for detecting the intake flow rate Q is provided in the intake passage 21. The intake air flow rate Q is a parameter corresponding to the flow rate of air that has passed through the air filter 22. An intake manifold pressure sensor 43 and an intake air temperature sensor 44 are provided in the surge tank 27. The intake manifold pressure sensor 43 detects the pressure in the surge tank 27 as intake manifold pressure, and the intake air temperature sensor 44 detects the intake air temperature in the surge tank 27.

  In the vicinity of the crankshaft, an engine rotation speed sensor 45 that detects an engine rotation speed Ne (the number of rotations per unit time) is provided. A cooling water temperature sensor 46 that detects the temperature of the engine cooling water (water temperature WT) is provided at an arbitrary position on the cooling water circulation path of the engine 10. Further, the high pressure pump 14A is provided with a fuel pressure sensor 50 that detects the pressure (fuel pressure) of the fuel injected from the in-cylinder injection valve 11.

  The electric actuator 18 is provided with a hall sensor 47 that detects the stroke amount of the rod 17b corresponding to the valve opening degree D. The hall sensor 47 is a position detection sensor using a hall element, and the valve position S is detected by the hall sensor 47. In addition, a linear air-fuel ratio sensor 48 and an oxygen concentration sensor 49 are disposed inside the catalyst device 33. The linear air-fuel ratio sensor 48 detects the air-fuel ratio of the exhaust gas flowing into the catalyst device 33, and the oxygen concentration sensor 49 detects the oxygen concentration of the exhaust gas flowing out from the catalyst device 33. Various information detected by the various sensors 41 to 50 is transmitted to the engine control device 1.

[1-5. Control system]
A vehicle equipped with the engine 10 is provided with an engine control device 1. The engine control device 1 is configured, for example, as an LSI device or an embedded electronic device in which a microprocessor, ROM, RAM, and the like are integrated, and is connected to a communication line of an in-vehicle network provided in the vehicle.

  The engine control device 1 is an electronic control device that comprehensively controls a wide range of systems such as an ignition system, a fuel system, an intake / exhaust system, and a valve system related to the engine 10. Air supplied to each cylinder of the engine 10 This controls the amount, fuel injection amount, ignition timing of each cylinder, supercharging pressure, and the like. The aforementioned various sensors 41 to 50 are connected to the input port of the engine control device 1. Input information includes accelerator opening APS, intake air flow rate Q, intake manifold pressure, intake air temperature, engine speed Ne, cooling water temperature WT, valve position S, exhaust air-fuel ratio, oxygen concentration, fuel pressure, and the like.

  Specific control objects of the engine control device 1 include the fuel injection amount and the injection timing injected from the in-cylinder injection valve 11 and the port injection valve 12, the ignition timing by the ignition plug 15, and the valve lifts of the intake valve and the exhaust valve. Examples include the amount and valve timing, the operating state of the turbocharger 16, the throttle opening, the opening of the bypass valve 24, the valve opening D of the waste gate valve 17, and the like.

  In the present embodiment, opening control of the waste gate valve 17 and learning control and cleaning control performed before the opening control is performed will be described. In addition, other controls (in this case, injection region control and fuel cut control), which are factors for determining whether or not to perform the cleaning control, will be described.

[2. Overview of control]
[2-1. Opening control]
The opening degree control is control for optimizing the valve opening degree D of the waste gate valve 17 in accordance with the operating state of the engine 10 and the magnitude of the output required for the engine 10. The accuracy of the opening control of the waste gate valve 17 affects the accuracy of the supercharging pressure control. In other words, if the valve opening degree D can be controlled with high accuracy, the accuracy of supercharging pressure control can be increased.

In the opening degree control, for example, the target of the valve opening degree D is determined based on the engine rotational speed Ne, the load P acting on the engine 10, the air amount, the charging efficiency Ec (target charging efficiency, actual charging efficiency, etc.), the accelerator opening APS, and the like. Value (target opening) D _TGT is set. Then, the rod 17b is controlled by the electric actuator 18 so that the set target opening degree D _TGT is obtained. In the opening degree control, the target opening degree D _TGT is set using the reference position _SBA and the reference operation range R _BA set in the learning control described below, and the valve opening degree D is controlled.

[2-2. Learning control]
The learning control is control for determining the reference position S _BA and the reference operation range R _BA of the waste gate valve 17 using the hall sensor 47. The reference position S _BA and the reference operation range R _BA are values serving as a reference when the opening degree of the waste gate valve 17 is controlled. The learning control includes first learning that is performed before the engine 10 is started and second learning that is performed after the engine 10 is started.

  The first learning is learning control that is performed only once during one drive cycle. Here, the first learning is performed before cranking after the ignition key is turned on (hereinafter referred to as key-on). On the other hand, the second learning is learning control that is performed many times during one drive cycle, and is performed during acceleration traveling here. Note that the drive cycle here means a period from key-on to key-on again. That is, the first learning is performed only once between the key-on and the key-off, and the second learning is performed a plurality of times between the key-on and the key-off.

In the first learning, the waste gate valve 17 is first controlled to be fully closed, and the valve position S at that time is detected by the hall sensor 47 and stored as the first fully closed position _SCL1 . Subsequently, the waste gate valve 17 is controlled to be fully open, and the valve position S at that time is detected by the hall sensor 47 and stored as the fully open position S _OP . From the first fully closed position S _CL1 and the fully open position S _OP The operating range R of the valve body 17a is calculated. Then, the initial fully closed position _ISCL and the initial operation range (width of the initial operation range) IR are learned from these detection results and calculation results. The initial fully closed position _ISCL and the initial operation range IR are values learned by the first learning, and are used for determining whether or not there is an abnormality in the system.

For example, the first fully closed position S _CL1 detected by the hall sensor 47 may be set (learned) as the initial fully closed position IS _CL as it is, or stored in the memory with the detected first fully closed position S _CL1. may be learned initial fully closed position iS _CL based on the in initial fully closed position iS _CL of the previous control which 'is. Here learned initial fully closed position IS _CL together with is stored in the memory, it is set as the reference position S _BA.

Further, for example, the calculated operation range R may be set (learned) as it is as the initial operation range IR, or the calculated operation range R and the initial operation range IR ′ at the previous control stored in the memory Based on the above, the initial operation range IR may be learned. The initial operation range IR learned here is stored in the memory and set as the reference operation range _RBA .

Further, in the second learning, the waste gate valve 17 is controlled to the fully closed valve position S at that time is detected by the Hall sensor 47, it is stored as the second fully closed position S _CL2, the second fully closed position S _A zero point S ₀ is learned from _CL2 . That is, in the second learning, the zero point S ₀ is learned from the fully closed position (second fully closed position S _CL2 ) during actual driving. By learning the zero point S ₀ including the effect of thermal expansion due to heat reception of the exhaust gas, the position control of the waste gate valve 17 can be performed with higher accuracy.

For example, the detected second fully closed position S _CL2 may be set (learned) as the zero point S ₀ as it is, or the detected second fully closed position S _CL2 and the previous control time stored in the memory it may be learned zero point S ₀ on the basis of the zero point S ₀ '. Here the zero point S ₀ learned in is stored in the memory.

Further, in the second learning, the zero point S ₀ is compared with the initial fully closed position IS _CL learned in the first learning, and the reference position S _BA (that is, the initial fully closed position IS _CL ) set in the first learning is compared. It is corrected by zero point S _0. For example, if the initial fully closed position IS _CL obtained in the first learning and zero point S ₀ obtained in the second learning are different, the reference position S _BA is zero S ₀ and the one set in the first learning The corrected reference position is used as the new reference position _SBA in the opening degree control. The initial if all the closed position IS _CL and zeros S ₀ are the same, the reference position S _BA, which is set in the first learning is used as such in the opening control (correction amount is set to 0).

[2-3. Cleaning control]
The cleaning control is control that is performed when a predetermined cleaning start condition is satisfied when a predetermined cleaning permission condition is satisfied. In the cleaning control, the waste gate valve 17 is forcibly opened and closed to perform cleaning. “Forced” here means that the waste gate valve 17 is opened and closed regardless of the above-described opening degree control.

  The waste gate valve 17 may be attached with carbon contained in the exhaust gas, and if the attached carbon adheres to the deposit, it may cause a malfunction of the waste gate valve 17. In particular, when fuel is injected by the in-cylinder injection valve 11, there is a high possibility that deposits are generated. Therefore, when a specific condition is satisfied, the waste gate valve 17 is cleaned to suppress carbon deposition.

  Here, the cleaning start condition includes that the vehicle is traveling at a reduced speed. For example, when the vehicle speed V is decreasing, such as when the brake pedal is being operated or when the vehicle is decelerating by coasting without the accelerator pedal being depressed. Further, the cleaning start condition includes that fuel cut control described later is being performed. That is, here, it is determined that the cleaning start condition is satisfied when the vehicle is traveling at a reduced speed and the fuel cut control is being performed.

  The cleaning is repeatedly performed such that the waste gate valve 17 is controlled to be fully opened after the waste gate valve 17 is controlled to be fully closed. That is, the opening / closing of the waste gate valve 17 is repeated regardless of the above-described opening / closing control. Thereby, the carbon adhering to the valve body 17a and the rod 17b is removed, and the carbon is removed from the waste gate valve 17. However, since the supercharging pressure changes when the waste gate valve 17 is opened and closed, the output may fluctuate due to cleaning.

  Therefore, in the present embodiment, the waste gate valve 17 is cleaned while the vehicle is traveling at a reduced speed and the fuel cut control is being performed. As a result, even if the supercharging pressure changes, the output is not affected. Further, since the cleaning is performed during the operation of the engine 10, the carbon removed from the waste gate valve 17 is blown off by the exhaust, and the carbon is more effectively removed.

  On the other hand, if the waste gate valve 17 is always cleaned when the above-described cleaning start condition is satisfied, cleaning is frequently performed, and excessive control may occur. Therefore, in this embodiment, the cleaning permission condition is determined before the cleaning start condition is determined. This cleaning permission condition determines whether or not cleaning may be performed (whether or not to perform cleaning). In the cleaning control, it is first determined whether or not the cleaning permission condition is satisfied, and the cleaning start condition is determined only when the cleaning permission condition is satisfied.

Here, the cleaning permission condition includes that the number of times of cleaning (the number of times of cleaning is performed) K during one drive cycle is less than a predetermined number of times K _P set in advance. The predetermined number K _P is set at least once. This is a condition for cleaning the waste gate valve 17 at least once during one drive cycle to suppress carbon deposition and prevent excessive cleaning. Under this condition, cleaning is not performed more than the predetermined number K _P in one drive cycle.

  In addition, the cleaning permission condition includes having experienced learning control. Here, if the second learning is performed at least once, it is assumed that learning control has been experienced. This is because the learning control is prioritized over the cleaning, and the reference of the opening control is quickly determined, thereby ensuring the accuracy of the opening control of the waste gate valve 17. Under this condition, the cleaning is not performed unless the second learning after the engine 10 is started.

Furthermore Here, cleaning permission condition, that the initial fully closed position IS _CL learned in the learning control and the zero point S ₀ is deviated more than a predetermined value S _P, and, DI + MPI in injection region control described later Satisfying at least one of modes that have been selected. In the former case, in order to carbon wastegate valve 17 had bites attached, is learned in the first learning the initial fully closed position IS _CL and zeros S ₀ learned by the second learning is large Since this may shift, learning accuracy is improved by permitting cleaning in such a case.

  In the latter case, that is, when fuel injection is performed by the in-cylinder injection valve 11, the exhaust flow rate increases as compared to fuel injection by only the port injection valve 12 (fuel injection in the MPI mode described later). The exhaust temperature becomes high. Therefore, by permitting cleaning in this case, carbon can be effectively removed from the waste gate valve 17.

[2-4. Injection area control]
The injection region control is control for properly using the fuel injection method in accordance with the operating state of the engine 10 and the output required for the engine 10. Here, for example, based on the engine rotation speed Ne, engine load P, air amount, charging efficiency Ec (target charging efficiency, actual charging efficiency, etc.), accelerator opening APS, etc., “MPI mode” that only performs port injection, One of “DI + MPI mode” in which fuel injection is performed using both port injection and in-cylinder injection is selected.

The MPI mode is a fuel injection mode that is selected when the engine 10 has a low load and a low rotation. In the MPI mode, fuel injection from the in-cylinder injection valve 11 is prohibited, and all of the fuel to be injected to obtain the required output is injected from the port injection valve 12. By performing the port injection, in the operation state with low load and low rotation, the good vaporization by the port injection is utilized and the homogeneity of the air-fuel mixture is improved, which leads to the improvement of the exhaust performance. Hereinafter, the amount of fuel injected from the port injection valve 12, also referred to as a port injection amount F _P.

  The DI + MPI mode is a fuel injection mode that is selected when the operating state of the engine 10 is not low load and low rotation (more than medium load or more than medium rotation). In the DI + MPI mode, fuel to be injected to obtain a required output is injected from the in-cylinder injection valve 11 and the port injection valve 12 at a predetermined ratio G. That is, both the in-cylinder injection valve 11 and the port injection valve 12 operate in the same combustion cycle, and both in-cylinder injection and port injection are performed. In the DI + MPI mode, the exhaust flow rate increases and the exhaust temperature increases as compared to the MPI mode.

When in-cylinder injection is performed, the temperature of the intake air and the temperature in the combustion chamber are reduced by the latent heat of vaporization of the fuel. This is called an intake air cooling effect, and this effect is advantageous for knocking, so that the compression ratio is increased. When the compression ratio is increased, the volume efficiency increases, so that the engine output can be increased and the fuel efficiency is improved. That is, in the DI + MPI mode, it is possible to obtain the merit of in-cylinder injection and the merit of port injection. Hereinafter, the amount of fuel injected from the in-cylinder injection valve 11, also referred to as in-cylinder injection quantity F _D.

Port injection amount for in-cylinder injection amount F _D F ratio of _{P G (= F P / F} D) are set in advance, DI + in MPI mode from the ratio G in cylinder injection valve 11 and the port injection valve 12 Each fuel is injected. Ratio G of the port injection quantity F _P for cylinder injection amount F _D is set to 0 <G <1 value. That is, the fuel injected from the in-cylinder injection valve 11 is more than the fuel injected from the port injection valve 12. Instead of the ratio G, the ratio G1 (= F _D / F _T ) of the in-cylinder injection amount F _D with respect to all the fuel amounts injected in one combustion cycle (the total fuel amount F _T described later), port injection quantity to the total fuel quantity F _T F ratio of _P G2 and (= F _P / F _T) may be set in advance. In this case, G1 ≧ G2, and G = G1 + G2.

[2-5. Fuel cut control]
The fuel cut control is a control for temporarily shutting off the fuel supply during operation of the engine 10 (the fuel injection amount is set to 0 or substantially 0). For example, the engine brake is operated without depression of the accelerator pedal. This is done when the vehicle is decelerating. On the other hand, when the accelerator pedal is depressed during the execution of the fuel cut control, or when the engine speed Ne drops to a relatively low speed range, the fuel cut control ends.

[3. Control configuration]
As shown in FIG. 1, the engine control apparatus 1 is provided with an engine load calculation unit 2, a waste gate calculation unit 3, an injection control unit 4 and a fuel cut control unit 5 as elements for performing the above-described control. . As shown in FIG. 2, the waste gate calculation unit 3 includes a learning unit 3a, an opening setting unit 3b, an opening control unit 3c, a cleaning determination unit 3d, and a cleaning control unit 3e.

  The injection control unit 4 includes a total fuel amount calculation unit 4a, an injection mode selection unit 4b, an injection amount setting unit 4c, and an injection control signal output unit 4d. Each of these elements may be realized by an electronic circuit (hardware), may be programmed as software, or some of these functions are provided as hardware, and the other part is software. It may be a thing.

[3-1. Engine load calculation unit]
The engine load calculation unit 2 calculates the magnitude of the load P of the engine 10. The load P here means a force that exerts resistance on the engine 10, a work rate (engine output, horsepower), a work (energy), and the like. Typically, an engine output required for the engine 10 and a parameter correlated therewith are handled as the load P.

  The load P is calculated based on the amount of air introduced into the cylinder, for example. Alternatively, it is calculated based on the intake flow rate, the exhaust flow rate, and the like. In addition, the load P may be calculated based on the intake pressure and exhaust pressure, the vehicle speed V, the rotational speed Ne, the accelerator operation amount APS, the operating state of the external load device, and the like. In the present embodiment, the charging efficiency Ec or the volumetric efficiency Ev is calculated based on the intake flow rate Q and the rotational speed Ne, and the magnitude of the load P is calculated based on these values. The value of the load P calculated here is transmitted to the waste gate calculation unit 3 and the injection control unit 4.

[3-2. Wastegate operation unit]
The learning unit (learning means) 3a performs the above-described learning control. That is, the learning unit 3 a performs the first learning before the engine 10 is started and performs the second learning after the engine 10 is started. Specifically, the learning unit 3a controls the full opening of the waste gate valve 17 after the key-on and before the engine 10 is started (reciprocates once from the fully closed state to the fully opened state).

At this time, the initial fully closed position IS _CL and the initial operating range IR are learned using the first fully closed position S _CL1 and the fully open position S _OP detected by the hall sensor 47 (first learning). Then, the initial fully closed position _ISCL and the initial operation range IR are set as the reference position _SBA and the reference operation range _RBA . The reference position S _BA and the reference operation range R _BA set here are transmitted to the opening setting unit 3b. Further, the initial closed position IS _CL learned in the first learning is transmitted to the cleaning determination unit 3d.

The learning unit 3a controls the waste gate valve 17 to be fully closed during acceleration traveling after the engine 10 is started. At this time, the zero point S ₀ is learned using the second fully closed position S _CL2 detected by the hall sensor 47 (second learning). Then, compared with the initial fully closed position IS _CL and zeros S _0, to correct the reference position S _BA. The corrected reference position _SBA is transmitted to the opening setting unit 3b. Further, the zero point S ₀ learned in the second learning is transmitted to the cleaning determination unit 3d.

  The learning unit 3a performs the first learning only once during one drive cycle, and the second learning is performed once or more during one drive cycle. Here, the learning unit 3a performs the second learning during acceleration traveling. However, after the second learning is performed once during acceleration, the second learning is performed when acceleration traveling is started again after a predetermined time has elapsed. This prevents the second learning from being repeated many times during one acceleration.

The opening setting unit 3b and the opening control unit 3c perform the above-described opening control. The opening setting unit 3b sets the target opening D _TGT of the waste gate valve 17 based on the operating state of the engine 10, and sets the valve position (target position S _TGT ) corresponding to the target opening D _TGT. is there. The target opening _DTGT is based on, for example, the engine speed Ne, the engine load P, the air amount, the charging efficiency Ec (target charging efficiency, actual charging efficiency, etc.), the supercharging pressure, the accelerator opening APS, the cooling water temperature WT, etc. Is set. The opening degree setting unit 3b sets a target position _STGT that becomes the set target opening degree D _TGT using, for example, a map as shown in FIG. 3, the horizontal axis valve opening D of the waste gate valve 17, the vertical axis is a map taking the valve position S, thereby the target position S _TGT corresponding to the target opening D _TGT is set.

Opening setting portion 3b, to the preset map (solid line in the figure), to reflect the transmitted reference position S _BA and the reference operation range R _BA from the learning unit 3a. Specifically, the opening setting unit 3b sets (updates) the transmitted reference position S _BA (white circle in the figure) as the valve position when the wastegate valve 17 is fully closed, and transmits the transmitted reference operation range R. _BA (one-dot chain line in the figure) is set (updated) as an operation range from the fully closed to fully opened waste gate valve 17. That is, the opening setting unit 3b adjusts the target position S _TGT corresponding to the target opening D _TGT using the learning result in the learning unit 3a. The target position _STGT set by the opening setting unit 3b is transmitted to the opening control unit 3c.

The opening control unit 3c outputs a control signal for the electric actuator 18 in accordance with the target position _STGT corresponding to the target opening D _TGT set by the opening setting unit 3b. Here, a control signal is output to the electric actuator 18 so that the actual valve position S becomes the target position _STGT . Thereby, the valve opening degree D is controlled to the target opening degree D _TGT .

The cleaning determination unit (determination unit) 3d and the cleaning control unit (cleaning control unit) 3e perform the above-described cleaning control. The cleaning determination unit 3d determines whether or not the waste gate valve 17 is to be cleaned. The cleaning determination unit 3d first determines whether or not both of the following conditions (A) and (B) are satisfied.
(A) The number K of cleanings performed in one drive cycle is less than the predetermined number K _P.
(B) The second learning is performed at least once.

The conditions (A) and (B) are both a part of the conditions for permitting cleaning (cleaning permitting conditions). If any one of the conditions (A) and (B) is not satisfied, the cleaning is not permitted (that is, the cleaning is not performed). Will not be implemented). The cleaning determination unit 3d stores, for example, the number of times that the cleaning start condition is satisfied (that is, the cleaning execution number K), and determines whether or not the condition (A) is satisfied. The condition (B) is determined based on whether or not the zero point S ₀ is transmitted from the learning unit 3a.

When it is determined that the conditions (A) and (B) are both satisfied, the cleaning determination unit 3d determines whether or not at least one of the following conditions (C) and (D) is satisfied. Note that if any one of the conditions (A) and (B) is not satisfied, the subsequent determination is not performed.
(C) Initial and fully closed position IS _CL and zeros S ₀ is deviated more than a predetermined value S _P.
(D) The DI + MPI mode has been selected.

Conditions (C) and (D) are a part of the cleaning permission conditions. Here, if either one is satisfied, cleaning is permitted. In other words, if neither condition is satisfied, cleaning is not permitted (cleaning is never performed). Cleaning determination unit 3d determines the condition (C) from an initial closed position IS _CL and zero point S ₀ which is transmitted from the learning unit 3a. Further, the condition (D) is determined based on information transmitted from an injection mode selection unit 4b of the injection control unit 4 described later.

The cleaning determination unit 3d determines that the cleaning permission condition is satisfied when the conditions (A) and (B) are satisfied and at least one of the conditions (C) and (D) is satisfied. It is determined whether or not both conditions (E) and (F) are satisfied. When the cleaning permission condition is not satisfied, the cleaning start condition is not determined.
(E) The vehicle is traveling at a reduced speed.
(F) The fuel cut control is being implemented.

  Conditions (E) and (F) are both part of the conditions for starting cleaning (cleaning start conditions), and cleaning is started when both conditions (E) and (F) are satisfied. In other words, if any one of the conditions (E) and (F) is not satisfied, the cleaning is not started. The cleaning determination unit 3d determines the condition (E) from, for example, the accelerator opening APS, the brake pedal switch, the vehicle speed V, and the like. Further, the condition (F) is determined based on information transmitted from the fuel cut control unit 5 described later.

When the conditions (E) and (F) are satisfied, the cleaning determination unit 3d determines that the cleaning start condition is satisfied, and transmits the information to the cleaning control unit 3e.
The cleaning control unit 3e performs cleaning by opening and closing the waste gate valve 17 when information indicating that the cleaning start condition is satisfied is transmitted to the cleaning determination unit 3d. The cleaning control unit 3e outputs a control signal for the electric actuator 18 so that the waste gate valve 17 is repeatedly opened and closed a predetermined number of times from when the cleaning start condition is satisfied. Thereby, the carbon adhering to the waste gate valve 17 etc. is removed.

[3-3. Injection control unit]
The injection control unit (injection control means) 4 controls the fuel injection by the in-cylinder injection valve 11 and the fuel injection by the port injection valve 12 to perform the injection region control.
Based on the engine speed Ne and the load P calculated by the engine load calculation unit 2, the total fuel amount calculation unit 4a determines the amount of fuel to be injected in one combustion cycle in order to obtain the required output. and it calculates a total fuel injection amount F _T. For example, a fuel injection amount map using the load P and the rotational speed Ne of the engine 10 as arguments is stored in the injection control unit 4 in advance, and the total fuel injection amount (that is, the total fuel amount F _T ) is calculated using this map. calculate. The total amount of fuel F _T calculated here is transmitted to the injection quantity setting unit 4c.

  The injection mode selection unit 4 b selects one of the above-described MPI mode and DI + MPI mode based on the operating state of the engine 10. The injection control unit 4 stores a map, an arithmetic expression, and the like that define the correspondence between the operating state of the engine 10 and the fuel injection mode. The fuel injection mode is selected based on such a map, arithmetic expression, and the like. A specific map, arithmetic expression, etc. are omitted here. The fuel injection mode selected by the injection mode selection unit 4b is transmitted to the injection amount setting unit 4c.

Injection amount setting unit 4c, according to the fuel injection mode selected by the injection mode selecting section 4b, and a port injection amount F _P from the cylinder injection amount F _D and the port injection valve 12 from the in-cylinder injection valve 11 It is to set. Injection amount setting unit 4c, upon this setting, the total fuel amount F _T calculated by the total fuel injection amount calculation unit 4a, and a ratio G which is set in advance is used. Here cylinder injection amount set in F _D and the port injection quantity F _P is transmitted to the injection control signal output unit 4d.

In accordance with the fuel injection mode selected by the injection mode selection unit 4b, the injection control signal output unit 4d secures the fuel injection amount set by the injection amount setting unit 4c and at a predetermined fuel injection timing. A control signal is output to the cylinder injection valve 11 and the port injection valve 12. The cylinder injection valve 11 and the port injection valve 12 that have received these control signals are driven at a time and a valve opening period corresponding to the control signals. Thereby, desired in-cylinder injection amount F _D and port injection amount _FP are injected at a predetermined fuel injection start timing.

[3-4. Fuel cut control unit]
The fuel cut control unit (fuel cut control means) 5 performs the above-described fuel cut control. Here, the fuel cut condition and the return condition are determined, and the amount of fuel injected from the in-cylinder injection valve 11 and the port injection valve 12 is controlled in accordance with the success or failure of these conditions. The fuel cut condition is, for example, that the accelerator opening APS is 0 and the engine rotational speed Ne is equal to or higher than the first predetermined rotational speed Ne ₁ . The return condition is, for example, that the accelerator opening APS is not 0, or that the engine rotational speed Ne is less than the second predetermined rotational speed Ne ₂ (Ne ₂ <Ne ₁ ). When it is determined that the fuel cut condition is satisfied, the fuel cut control unit 5 transmits the information to the cleaning determination unit 3d.

[4. flowchart]
4 to 6 are flowcharts for explaining the respective procedures of learning control, opening degree control, and cleaning control. Each of these flowcharts is started with key-on, and is repeatedly executed at a predetermined calculation cycle set in advance in the engine control device 1.

First, the learning control performed in the learning unit 3a will be described. As shown in FIG. 4, in step W10, it is determined whether or not the flag F ₁ is F ₁ = 0. Here, the flag F ₁ is a variable for checking whether or not the first learning has already been performed, and F ₁ = 0 corresponds to the fact that the first learning has not been performed yet, and F ₁ = 1. Corresponds to having already completed the first learning. When the flag F ₁ is F ₁ = 0, the process proceeds to Step W20, and when F ₁ = 1, the process proceeds to Step W70.

First learning is performed in steps W20 to W40. That is, in step W20, the valve position (first fully closed position) _SCL1 when the waste gate valve 17 is fully closed is detected, and the valve position (fully opened) when the waste gate valve 17 is fully opened. Position) S _OP is detected, and the operating range R is calculated. In the subsequent step W30, the initial fully closed position _ISCL and the initial operation range IR are learned. Then, in step W40, with the initial fully closed position IS _CL is set to the reference position S _BA, initial operation range IR is set to the reference operation range R _BA.

In the subsequent step W50, the reference position _SBA and the reference operation range _RBA are transmitted to the opening setting unit 3b, and the initial fully closed position _ISCL is transmitted to the cleaning determination unit 3d. In step W60, the flag F ₁ is set to F ₁ = 1. Thus, the processing from step W20 to step W60 is performed only when the flag F ₁ is F ₁ = 0 immediately after key-on (that is, before the engine 10 is started).

In step W70, it is determined whether the vehicle is accelerating. If during the acceleration running proceeds to step W80, if not in the acceleration running, the process proceeds to step W1 65. In Step W80, it is determined whether or not the flag F ₂ is F ₂ = 0. Here, the flag F ₂ is a variable for checking whether or not the second learning can be performed. F ₂ = 0 corresponds to that the second learning can be performed, and F ₂ = 1 is the first learning. Corresponding to the fact that second learning is not possible. The second learning is performed many times during one drive cycle, but once it is performed, it is performed again after a predetermined time has elapsed. This flag F ₂ is for checking whether or not a predetermined time has passed. When the flag F ₂ is F ₂ = 0, the process proceeds to Step W90, and when the flag F ₂ is F ₂ = 1, the process proceeds to Step W140.

In steps W90 to W110, the second learning is performed. That is, in step W90, the valve position when the waste gate valve 17 is fully closed (the second fully closed position) S _CL2 is detected. When the process proceeds to step W90, the acceleration gate is running, so the waste gate valve 17 is normally controlled to be fully closed. That is, by performing the second learning during the acceleration traveling in which the waste gate valve 17 is controlled to be fully closed, the learning control can be performed with little influence on the traveling.

In step W100, zero point S ₀ is learned. In step W110, the reference position S _BA is corrected by zero point S ₀ learned. In step W120, the reference position S _BA corrected in opening setting portion 3b is transmitted, the zero point S ₀ is transmitted to the cleaning determination unit 3d. In step W130, the flag F ₂ is set to F ₂ = 1, and it is determined whether the process proceeds to step W170 and the key is turned off. If the key remains on, this flow is returned.

In the next cycle, the process proceeds from step W10 to step W70, and if acceleration traveling is continued, the process proceeds to step W80. Here, since the flag F ₂ is set to F ₂ = 1 in the previous cycle, the process proceeds to step W140, and 1 is added to the count value C. In step W150, the count value C is equal to or a predetermined value C ₀ or more is determined. If the count value C is less than the predetermined value C ₀ , the process proceeds to step W170. If the key is not keyed off, this flow is returned.

Similarly, in the next cycle, when the process proceeds to step W140, 1 is added to the count value C, and the determination in step W150 is performed. In step W150, the count value C is calculation time is repeated until it is determined that the predetermined value C ₀ or higher, after implementing the second learning once, then corresponds to a predetermined time to implement. When the count value C becomes equal to or greater than the predetermined value C ₀ , the process proceeds to step W160, the flag F ₂ is reset to F ₂ = 0, the count value C is reset to 0, and the process proceeds to step W170. If the acceleration travel is finished while the count value C is being added, the process proceeds from step W70 to step W165, the flag F ₂ is reset to F ₂ = 0, and the count value C is reset to 0. Then, the process proceeds to Step W170.

If it is determined in step W170 that the key has been turned off, the process proceeds to step W180 where both the flags F ₁ and F ₂ are reset to 0 and the count value C is reset to 0, and this flow ends. When the key is turned on again, the processing from step W10 is performed.

Next, the opening degree control implemented in the opening degree setting part 3b and the opening degree control part 3c is demonstrated. As shown in FIG. 5, in step X <b> 10, various information detected by the various sensors 41 to 50 is input to the engine control device 1. Further, the engine load calculation unit 2 calculates the load P of the engine 10, and information on the load P is transmitted to the opening setting unit 3b. In step X20, the target opening degree D _TGT of the waste gate valve 17 is set in the opening degree setting part 3b.

In step X30, valve opening D and the reference positional relationship is transmitted from the learning unit 3a to a map set with the valve position S S _BA and a reference operating range R _BA is reflected. At step X40, it sets the target position S _TGT corresponding to the target opening degree D _TGT that has been set. In step X50, the opening control unit 3c outputs a control signal to the electric actuator 18 so that the actual valve position S becomes the set target position _STGT, and the flow returns.

  Finally, cleaning control performed in the cleaning determination unit 3d and the cleaning control unit 3e will be described. As shown in FIG. 6, in step Y10, it is determined whether or not the key is off. If the key-on state is continuing, the process proceeds to step Y20. If the key-off state is keyed, the process proceeds to step Y130. In step Y20, it is determined whether or not the flag A is A = 0. Here, the flag A is a variable (permission flag) for checking whether or not the cleaning permission condition is satisfied, A = 1 corresponds to the satisfaction of the cleaning permission condition, and A = 0 indicates that the cleaning permission condition is not satisfied. Correspond. If the flag A is A = 0, the process proceeds to step Y30. If A = 1, the process proceeds to step Y80.

In step Y 30, the cleaning execution number K is determined whether it is less than the predetermined number of times K _P, if it is less than the predetermined number K _P proceeds to step Y40, the case of a predetermined number of times or more K _P (i.e., a predetermined cleaning count If K _{P is} implemented), this flow is returned. In step Y40, whether zero point S ₀ from the learning section 3a are transmitted (i.e., whether the step W120 in the flowchart of FIG. 4 is performed) it is determined. If the zero point S ₀ is not transmitted, the flow returns, and if the zero point S ₀ is transmitted, the process proceeds to step Y50. Determination in step Y40, the process proceeds along the YES route if it is practiced the step W120 is once in the flowchart of FIG. 4, a new zero point S ₀ each time the zero point S ₀ is learned is transmitted, in the next step Y50 zero point S ₀ used is updated. Note that the determinations in step Y30 and step Y40 correspond to the above conditions (A) and (B), respectively.

In step Y50, whether the difference between the initial fully closed position IS _CL and zeros S ₀ (absolute value of the initial fully closed position minus the zero point S ₀ from IS _CL) is equal to or larger than the predetermined value S _P is Determined. Difference between the initial fully closed position IS _CL and zeros S ₀ is equal to or larger than the predetermined value S _P, the flag A in step Y70 is set to A = 1. On the other hand, the initial if the difference between the fully closed position IS _CL and zeros S ₀ is less than the predetermined value S _P is whether it may have experienced DI + MPI mode at step Y60 (i.e., DI + MPI mode Whether or not it has been selected) is determined. These determinations at step Y50 and step Y60 correspond to the above conditions (C) and (D), respectively. If the DI + MPI mode has been selected, the process proceeds to step Y70, and if the DI + MPI mode has not been selected, this flow is returned.

  Since the flag A is set to A = 1 in step Y70, the process proceeds from step Y20 to step Y80 from the next calculation cycle. That is, once the cleaning permission condition is satisfied, the flag A remains A = 1 until cleaning is performed or key-off is performed. In step Y80, it is determined whether or not the vehicle is decelerating. If the vehicle is decelerating, the process proceeds to step Y90. If the vehicle is not decelerating, the process returns.

  In step Y90, it is determined whether or not the fuel cut control is being performed. If the fuel cut control is being performed, the process proceeds to step Y100, and if the fuel cut control is not being performed, this flow is returned. These determinations at step Y80 and step Y90 correspond to the above conditions (E) and (F), respectively. In step Y100, the waste gate valve 17 is opened and closed to perform cleaning.

  In step Y110, 1 is added to the cleaning execution count K, and in step Y120, the flag A is reset to A = 0, and this flow is returned. If the key is turned off, the process proceeds from step Y10 to step Y130, both the flags A and K are reset to 0, and this flow ends.

[5. effect]
(1) In the engine control apparatus 1 described above, the cleaning start condition includes that the vehicle is traveling at a reduced speed, so that a sufficient cleaning time can be secured, and the opening portion of the waste gate valve 17 and the exhaust bypass passage 32 can be secured. Carbon attached to the periphery can be removed. Further, if the cleaning is performed during the deceleration traveling, the carbon removed from the waste gate valve 17 and the like is blown off by the flow of the exhaust gas, so that it does not accumulate in the exhaust bypass passage 32 and the generation of deposits can be suppressed. .

  (2) In the engine control apparatus 1 described above, the fuel cut control unit 5 is provided, and the cleaning start condition includes that the fuel cut control is being performed. Therefore, the cleaning is performed without affecting the traveling. can do. That is, since cleaning is performed by opening and closing the waste gate valve 17, the supercharging pressure changes. On the other hand, if cleaning is performed during the fuel cut control, carbon can be removed without affecting the output even if the supercharging pressure changes.

  (3) In the engine control apparatus 1 described above, whether or not the cleaning permission condition is satisfied is determined before the cleaning start condition is determined. That is, if the cleaning permission condition is not satisfied, the cleaning start condition is not determined. Therefore, depending on the setting of the cleaning permission condition, the timing for performing cleaning can be set appropriately.

(4) In the above-described engine control device 1, the cleaning permission condition, the zero point S ₀ is learned by the learning section 3a (i.e., the second learning is performed) are included. In other words, since the learning value that serves as a reference for opening control of the waste gate valve 17 is first secured and then cleaning is performed, the opening control of the waste gate valve 17 can be accurately performed.
In addition, the second learning is learned after the valve element 17a and the rod 17b of the waste gate valve 17 receive heat from the exhaust, so that it is possible to learn including the influence of thermal expansion and the like. The accuracy of control is improved.

(5) In the above-described engine control device 1, the cleaning permission condition, the difference between the zero point S ₀ learned the initial fully closed position IS _CL learned by the first learning second learning than the predetermined value S _P It is included. Thereby, when the learning value has shifted due to the adhesion of carbon, the shifting can be eliminated, and the learning can be performed accurately. In other words, after eliminating the factor of carbon adhesion, learning can be improved by learning again. Further, by increasing the learning accuracy in this way, it is possible to determine the failure of the waste gate valve 17 using the learning values (the initial fully closed position _ISCL and the zero point S ₀ ).

  (6) In the engine control apparatus 1 described above, in-cylinder injection and port injection are performed within the same combustion cycle (that is, fuel injection in DI + MPI mode is performed) under the cleaning permission condition. Is included. In the DI + MPI mode, the exhaust gas temperature is higher than that in the MPI mode in which only port injection is performed, so that the carbon adhering to the waste gate valve 17 and the like is not easily burned and deposited. Furthermore, in the DI + MPI mode, the exhaust flow rate increases, so that the burned carbon can be reliably removed by performing cleaning after experiencing the DI + MPI mode. That is, the waste gate valve 17 can be effectively cleaned by including the DI + MPI mode in the cleaning permission condition.

[6. Others]
Regardless of the embodiment described above, various modifications can be made without departing from the spirit of the invention. Each structure of this embodiment can be selected as needed, or may be combined appropriately.

  The cleaning permission condition described in the above embodiment is an example, and is not limited to the above. Any one or more of the above conditions (A) to (D) may be set as the cleaning permission condition, and other conditions may be set as the cleaning permission condition. For example, when the cleaning permission condition is that a predetermined time has elapsed since the cleaning was completed, frequent cleaning can be suppressed. Further, in the MPI mode in which only the port injection is performed, carbon easily adheres to the waste gate valve 17, so that the cleaning permission condition may be that the MPI mode is experienced instead of the condition (D). Thereby, carbon deposition can be suppressed.

  In the above embodiment, the cleaning start condition is determined when the cleaning permission condition is satisfied. However, the cleaning permission condition may be omitted. In other words, it may be determined whether or not the cleaning start condition is satisfied, and the cleaning may be performed when the cleaning start condition is satisfied. The cleaning start condition is not limited to the above, and it is sufficient that at least the condition (E) is included. That is, it is only necessary to include that the vehicle is traveling at a reduced speed, and cleaning may be performed even when the fuel cut control is not being performed.

In addition, when a predetermined condition (running idle stop execution condition) is established while the vehicle is running, if there is an idle stop function that automatically stops the engine 10, cleaning is performed even when the condition is established. If not, it is preferable to prioritize cleaning.
That is, as shown by broken lines in FIGS. 1 and 2, the running idle stop control unit (running idle stop control means) 6 provided in the engine control device 1 performs cleaning when the running idle stop execution condition is satisfied. Check the implementation status of. If the cleaning has never been performed during one drive cycle, the automatic stop of the engine 10 is prohibited even when the idle stop execution condition is established during traveling. As a result, carbon deposition on the waste gate valve 17 can be reliably prevented. The running idle stop execution conditions include, for example, that the vehicle is traveling at a reduced speed, and that the vehicle speed V is equal to or lower than a predetermined speed.

Further, the learning unit 3a, the injection control unit 4, the fuel cut control unit 5 and the like in the above embodiment are examples, and the specific configuration is not limited to the above. In the above embodiment, by reflecting the reference position S _BA set by the learning unit 3a to the map, while setting the target position S _TGT corresponding to the target opening degree D _TGT, using learning result in opening control The method is not limited to this. For example, the fully closed position of the waste gate valve 17 is stored in advance as the initial reference position, and the deviation amount between the reference position _SBA set by the learning unit 3a and the initial reference position is calculated. Then, a target position _STGT corresponding to the target opening degree D _TGT is set using a preset map shown by a solid line in FIG. 3, and the opening degree control is performed by adding and subtracting the deviation amount to the set target position _STGT. You may transmit to the part 3c.

Further, in the above embodiment, has learned the initial fully closed position IS _CL and the initial operating range IR at a first learning may be carried out learning of at least the initial fully closed position IS _CL. By using this initial fully closed position _ISCL as a reference at the time of opening control, the opening control can be performed with high accuracy, and the accuracy of supercharging pressure control can be increased.
Moreover, although the case where the first learning was performed before cranking after key-on was illustrated in the above embodiment, it may be performed during cranking before the engine 10 is started. Moreover, although the case where 2nd learning was implemented during acceleration driving | running | working was illustrated, 2nd learning can be implemented if the engine 10 is start-up. Further, the second learning may be performed once during one drive cycle.

Further, the fuel cut condition and the return condition are not limited to those described above. For example, vehicle speed information, intake manifold pressure information, and the like may be considered.
Further, the configuration of the engine 10 is not limited to the above-described configuration, and any engine including an electric waste gate valve interposed in a bypass route that bypasses the supercharging turbine on the exhaust passage is applicable. The means for detecting the position of the waste gate valve 17 is not limited to the hall sensor 47, and any means capable of detecting the position of the valve body 17a of the waste gate valve 17 and the stroke amount of the rod 17b may be used.

DESCRIPTION OF SYMBOLS 1 Engine control apparatus 2 Engine load calculation part 3 Waste gate calculating part 3a Learning part (learning means)
3b Opening setting unit 3c Opening control unit 3d Cleaning determination unit (determination means)
3e Cleaning control unit (cleaning control means)
4 Injection control unit (injection control means)
5 Fuel cut control unit (fuel cut control means)
6 Traveling idle stop control unit (traveling idle stop control means)
DESCRIPTION OF SYMBOLS 10 Engine 11 In-cylinder injection valve 12 Port injection valve 16 Turbocharger 16A Turbine (supercharging turbine)
17 Waste gate valve 17a Valve body 17b Rod 18 Electric actuator 31 Exhaust passage 32 Exhaust bypass passage (bypass)
47 Hall sensor (detection means)
IS _CL initial fully closed position
S ₀ Zero point

Claims (6)

An engine control device including a waste gate valve that is interposed in a bypass route that bypasses a supercharged turbine on an exhaust passage and is driven by an electric actuator,
Determining means for determining whether or not a predetermined cleaning start condition is satisfied;
A cleaning control means for performing cleaning by opening and closing the waste gate valve when the determination means determines that the cleaning start condition is satisfied;
The determination means determines whether a predetermined cleaning permission condition is satisfied, determines whether the cleaning start condition is satisfied when the cleaning permission condition is satisfied,
The engine control apparatus according to claim 1, wherein the cleaning start condition includes that the vehicle is traveling at a reduced speed. Comprising fuel cut control means for performing fuel cut control for cutting off fuel supply during operation of the engine;
2. The engine control apparatus according to claim 1, wherein the cleaning start condition includes that the fuel cut control by the fuel cut control means is being performed . Detecting means for detecting a position of the waste gate valve;
Learning means for learning the zero point of the waste gate valve from the position detected by the detection means by fully closing the waste gate valve after starting the engine;
The engine control apparatus according to claim 1 or 2 , wherein the cleaning permission condition includes that the zero point has been learned by the learning unit. The learning means learns the initial fully closed position of the waste gate valve from the position detected by the detecting means by fully closing the waste gate valve before starting the engine,
Wherein the cleaning permission condition is characterized to include the absolute value of the difference between the zero point and the initial closed position learned by the learning means is a predetermined value or more, according to claim 3, wherein Engine control device. An injection control means for controlling in-cylinder injection that is fuel injection into the cylinder of the engine and port injection that is fuel injection into the intake port of the cylinder based on the operating state of the engine;
The cleaning permission condition is characterized by the said port injection and the direct injection in the same combustion cycle involves carried out by the injection control means, one of claims 1 to 4 1 The engine control device according to Item. A traveling idle stop control means for automatically stopping the engine during traveling of the vehicle when a predetermined traveling idle stop execution condition is satisfied;
The running idle stop control means prohibits the automatic stop of the engine when the cleaning by the cleaning control means is not executed even when the running idle stop execution condition is satisfied. The engine control device according to any one of claims 1 to 5 .

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