JP4710804B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine. More specifically, the present invention relates to a control device capable of controlling the output generated by the internal combustion engine by two output control means capable of changing the output of the internal combustion engine.

  In an in-vehicle internal combustion engine, when the generated torque rapidly increases and shifts to an acceleration state, distortion may occur in the transmission system that transmits the output of the internal combustion engine to the drive wheels, and vibration may be generated by this restoring force. This vibration causes fluctuations in the acceleration of the vehicle, and the vehicle is oscillated back and forth in the traveling direction. In order to suppress such vibrations, for example, Japanese Patent Laid-Open No. 2000-356153 discloses that the torque generated by the internal combustion engine is controlled by controlling the opening of the throttle valve and the ignition timing at the time of transition to the acceleration state. A system is disclosed.

  Specifically, when this system detects that the internal combustion engine shifts to the acceleration state, first, the throttle opening is controlled to be opened more than the original opening with respect to the operation state of the internal combustion engine at that time for a predetermined period. . As a result, the intake air amount is increased from the intake air amount required in the current operating state. Therefore, the internal combustion engine is in a state where it can generate a torque that is greater than the required torque according to the operating state. In this state, the direction and magnitude of the acceleration fluctuation of the vehicle that occurs when the internal combustion engine shifts to the acceleration state is estimated, and the ignition timing is adjusted so that torque having an opposite phase to the acceleration fluctuation is generated. As a result, the generated torque is a torque that cancels out the acceleration fluctuation generated in the vehicle, and the vibration generated in the vehicle at the time of transition to the acceleration state is reduced.

JP 2000-356153 A JP 2001-186602 A JP-A-2005-330921 Japanese Patent Laid-Open No. 11-62690

  By the way, in a system such as the above prior art, a torque map that defines the relationship between the generated torque and the intake air amount or the throttle opening, and a torque map that defines the relationship between the generated torque and the ignition timing are stored in the system in advance. Has been. When controlling the torque as in the above-described prior art, the intake air amount and the throttle opening are calculated according to the set target torque based on such a torque map, and according to the target torque. Thus, the ignition timing is calculated based on the map related to the ignition timing.

  However, for example, even if the throttle valve is set to the throttle opening calculated according to the torque map, a predetermined amount of intake air may not be sucked due to the influence of the intake deposit or the like. Further, even if the required amount of intake air is sucked, there is a case where fuel corresponding to the amount of fuel is not injected due to deterioration of the fuel injection device or the like, and torque as required is not generated. Further, due to deterioration of the ignition device, ignition may not be performed at the ignition timing calculated according to the torque map, and torque as requested may not be generated. Thus, there may be a deviation in the torque map of the generated torque related to the intake air amount and the ignition timing. When a deviation occurs in the torque map, for example, a deviation also occurs in the torque control of the internal combustion engine such as torque control for reducing acceleration vibration, and it may be difficult to generate the target torque.

  In addition, such a situation is not limited to controlling the output of the internal combustion engine by controlling the throttle opening and the ignition timing, but the other two control means are used to control the output of the internal combustion engine. In some cases. That is, when the control amounts of two different control means are set based on the respective maps with respect to the target output, the output of the internal combustion engine is reduced in a state where the control means maps are misaligned. The target output may not be accurately controlled.

  Accordingly, an object of the present invention is to solve the above-mentioned problems, and when the output of the internal combustion engine is controlled by two different control means, it is used when setting the respective control amounts for the two different control means. It is an object of the present invention to provide a control apparatus for an internal combustion engine which is improved so that a map to be corrected can be corrected.

In order to achieve the above object, the first invention provides
First output changing means for changing the output of the internal combustion engine;
Second output changing means for changing the output with responsiveness different from that of the first control means;
A control device for controlling an internal combustion engine comprising:
According to a first map that defines the relationship between the output of the internal combustion engine and the control amount of the first output changing means, the output of the internal combustion engine is a target output that is different from the required output by a predetermined output, First control amount calculating means for calculating a first control amount for the first output changing means;
First control means for controlling the first output changing means to the first control amount;
Second control means for controlling the second output change means so that the internal combustion engine emits the required output in a state where the first output change means is controlled to the first control amount;
An actual control amount detecting means for detecting an actual control amount that is an actual control amount for the second output changing means by the second control means;
Based on the actual control amount, correction of the second map that determines the control amount of the second output change means with respect to the first map and / or the output of the internal combustion engine and the control amount of the first output change means is performed. Map correction means to perform,
It is characterized by providing.

  A second invention is characterized in that, in the first invention, the output of the internal combustion engine is controlled by using the rotational speed of the internal combustion engine as a parameter.

According to a third invention, in the first or second invention,
The first output changing means is a throttle valve disposed in an intake passage of the internal combustion engine,
The first control means controls the opening of the throttle valve.

According to a fourth invention, in any one of the first to third inventions,
The second output changing means is an internal combustion engine ignition device,
The second control means controls timing of ignition by the ignition device.

According to a fifth invention, in any one of the first to fourth inventions,
The predetermined output is a periodic fluctuation output in which the output changes at a constant period,
The control device for the internal combustion engine includes an output generated by the internal combustion engine in a state where the first output changing unit is controlled to the first control amount and the second output changing unit is controlled by the second control unit. Periodic variation determining means for determining the disappearance of the periodic variation when the periodic variation of the is less than the reference value,
The actual control amount detecting means detects a control amount for the second output changing means in a state where the disappearance of the periodic fluctuation is recognized as the actual control amount.

A sixth invention is any one of the first to fifth inventions,
When the first output changing means is controlled to the first control amount according to the second map, the second control amount for the second output changing means such that the output of the internal combustion engine becomes the required output. Further comprising a second control amount calculating means for calculating
The map correction means corrects the first map and / or the second map based on a difference between the second control amount and the actual control amount.

In order to achieve the above object, the seventh invention provides
First output changing means for changing the output of the internal combustion engine;
Second output changing means for changing the output with a response different from that of the first output changing means;
An internal combustion engine control device comprising:
According to a first map that defines the relationship between the output of the internal combustion engine and the control amount for the first output changing means, the output of the internal combustion engine is a target output that is different from the required output by a predetermined output, First control amount calculating means for calculating a first control amount for the first output changing means;
The first output change means is controlled to the first control amount according to a second map that defines the control amount of the second output change means with respect to the output of the internal combustion engine and the control amount of the first output change means. A second controlled variable calculating means for calculating a second controlled variable for the second output changing means so that the output of the internal combustion engine becomes a required output.
First control means for controlling the first output changing means to the first control amount;
Second control means for controlling the second output changing means to the second control amount;
An actual output detecting means for detecting an actual output of the internal combustion engine in a state where the first output changing means is controlled to the first control amount and the second output changing means is controlled to the second control amount;
Map correction means for correcting the first map and / or the second map according to a difference between the target output and the actual output;
It is characterized by providing.

  According to the first aspect of the invention, the actual output becomes the required output in a state where the first output changing means is controlled so that the output of the internal combustion engine becomes a target output different from the required required output by a predetermined output. In addition, control by the second output changing means is performed. Then, an actual control amount that is an actual control amount for the second changing means in this control is detected, and the first map and / or the second map is corrected based on the detected actual control amount. Therefore, when there is a shift in the map, the map can be corrected so as to correct the shift generated in the output in the output control of the internal combustion engine by the two control means, thereby realizing more accurate control of the internal combustion engine. can do.

  According to the second invention, the output of the internal combustion engine is controlled using the rotational speed of the internal combustion engine as a parameter. Thereby, the control for correcting the map can be realized in a state suitable for the actual operation of the internal combustion engine.

  According to the third invention, the output of the internal combustion engine is controlled by controlling the opening of the throttle valve. Therefore, more accurate output control of the internal combustion engine by increasing the intake air amount can be realized.

  According to the fourth aspect of the invention, the output of the internal combustion engine is controlled by controlling the ignition timing, and the map can be corrected in the relationship between the map for determining the ignition timing and the map relating to the first control means. Therefore, more accurate output control of the internal combustion engine by controlling the ignition timing can be realized.

  According to the fifth aspect of the invention, the target output is an output obtained by adding a periodic fluctuation in which the output changes at a constant cycle to the required output, and the internal combustion engine is controlled in the state where the first output changing means is controlled to the first control amount. The second control means is controlled so that the periodic fluctuation of the engine output disappears, and the deviation of the map is detected based on the control amount at this time. In this way, by controlling the second control means so as to cancel the influence of the periodic fluctuation, even when the operating state of the internal combustion engine changes and the required output itself changes, the influence of the change in the required output is eliminated. Thus, the deviation between the first and second maps can be corrected.

  According to the sixth invention, based on the second map, when the first output changing means is controlled to the first control amount, the second output changing means for making the output of the internal combustion engine the required output. Two control amounts are calculated, and the first map and / or the second map can be corrected based on the difference between the calculated value and the actual control amount.

  According to the seventh aspect of the present invention, the output becomes the required output while the first output changing means is controlled so that the target output is different from the required output required for the output of the internal combustion engine. A control amount for the output changing means is calculated, and the second output changing means is controlled based on the calculated value. In such a state, the actual output of the internal combustion engine is detected, and the first and second maps are corrected based on the difference between the actual output and the required output. Therefore, when there is a shift in the map, the map can be corrected so as to correct the shift generated in the output in the output control of the internal combustion engine by the two control means, thereby realizing more accurate control of the internal combustion engine. can do.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is simplified or omitted.

Embodiment 1 FIG.
[System configuration of the first embodiment]
FIG. 1 is a schematic diagram for illustrating a configuration of an internal combustion engine system according to Embodiment 1 of the present invention. The system shown in FIG. 1 includes an internal combustion engine 10. The internal combustion engine 10 includes a cylinder 12. Although only a cross section of one cylinder 12 is shown in FIG. 1, the internal combustion engine 10 actually includes a plurality of cylinders 12. A piston 14 is disposed inside the cylinder 12. The piston 14 is connected to a crankshaft (not shown) via a connecting rod. In the vicinity of the crankshaft, a rotational speed sensor 16 that emits an output corresponding to the engine rotational speed of the internal combustion engine 10 is disposed.

  A combustion chamber 18 is provided above the piston 14 in the cylinder 12. A spark plug 20 (second output changing means) is assembled at the center of the ceiling (cylinder head) of the combustion chamber 18 so that the gap at the tip protrudes into the combustion chamber 18. The spark plug 20 ignites the fuel supplied into the combustion chamber by discharge. The ignition timing by the spark plug 20 is electrically controlled via the actuator 22.

  An intake valve 26 is disposed at the intake port 24 of each cylinder 12 of the internal combustion engine 10, and an exhaust valve 30 is disposed at the exhaust port 28. Variable valve mechanisms 32 and 34 are connected to the intake valve 26 and the exhaust valve 30, respectively. The variable valve mechanisms 32 and 34 are mechanisms that can vary the opening / closing timing and lift amount of the intake valve 26 or the exhaust valve 30. Further, the port injector 36 is assembled with the injection port at the front end directed into the intake port 24. The port injector 36 is a fuel injection device that injects fuel into the intake port 24, and the injected fuel is mixed with air in the intake port 24 and sucked into the cylinder 12.

  A common intake pipe 40 is connected to the intake port 24 of each cylinder 12. The intake pipe 40 is provided with an electronically controlled throttle valve 42 (first output changing means). The throttle valve 42 adjusts the amount of air flowing into the intake pipe 40 by changing its opening. The opening degree of the throttle valve 42 (throttle opening degree) is electrically controlled via an actuator 44 based on an acceleration / deceleration request by an accelerator operation or the like. That is, the throttle opening can be controlled independently of the accelerator opening. An air flow meter 46 is disposed in the intake pipe 40 upstream of the throttle valve 42. The air flow meter 36 generates an output corresponding to the air flow rate flowing into the intake pipe 40.

  The internal combustion engine system of the first embodiment includes an ECU (Electronic Control Unit) 50 as a control device for the internal combustion engine. The ECU 50 is connected to various sensors such as the rotation speed sensor 16, the air flow meter 46, and the accelerator opening sensor 52, and acquires information related to the operation state of the internal combustion engine 10 from these sensors. The ECU 50 is connected to the actuator 22 of the spark plug 20, the actuator 44 of the throttle valve, the variable valve mechanisms 32, 34, etc., and based on the acquired information, the ignition timing, throttle opening, intake / exhaust valve opening / closing timing, etc. A control signal for controlling is issued.

[Control of throttle opening and ignition timing]
FIG. 2 is a diagram illustrating the relationship between the intake air amount and the torque. In FIG. 2, the horizontal axis represents the intake air amount, and the vertical axis represents the torque. It can be seen from FIG. 2 that the generated torque increases as the intake air amount increases. That is, when the required torque is large, a large amount of intake air is required, and when the required torque is small, the necessary intake air amount is also small. Further, the intake air amount changes according to the opening of the throttle opening. The basic throttle opening during normal operation of the internal combustion engine 10 is set larger as the required torque increases, and is set smaller when the required torque is smaller.

  The ECU 50 stores in advance a torque map 1 (first map) that defines the relationship between the intake air amount and the torque as shown in FIG. 2, and a throttle opening calculation formula corresponding to the intake air amount. During normal operation of the internal combustion engine 10, the intake air amount corresponding to the required torque is calculated according to the torque map 1, and the basic throttle opening is set according to the calculated intake air amount.

  By the way, the torque in the above torque map 1 is ignited at an ignition timing (MBT: minimum advance for the best torque) where the engine output and the fuel consumption rate are estimated to be the best in relation to the intake air amount and the engine speed. This is the torque generated when Therefore, the relationship between the torque and the intake air amount is different when the engine speed is different. Therefore, the torque map 1 showing the relationship between the torque and the intake air amount is determined for each predetermined engine speed and stored in the ECU 50.

  FIG. 3 is a diagram for explaining the relationship between the ignition timing MBT and the torque. In FIG. 3, the horizontal axis represents ignition timing and the vertical axis represents torque. As shown in FIG. 3, when the required torque is large, the ignition timing is earlier. Here, the ignition timing in FIG. 3 is the ignition timing MBT that is estimated to have the best engine output and fuel consumption rate. The ignition timing MBT is determined according to the engine speed and the intake air amount. That is, the relationship between the ignition timing and the torque as shown in FIG. 3 is different when the engine speed and the intake air amount are different. The ECU 50 stores a torque map 2 (second map) that defines the relationship between torque and ignition timing for each engine speed and intake air amount.

  As described above, the intake air amount and the ignition timing control the torque of the internal combustion engine 10 with each other, and each is set to an optimal control amount to generate a torque corresponding to the required torque. However, for example, when intake deposits are accumulated on the intake valve 26 or the intake port 24, the intake air amount corresponding to the calculated throttle opening is not supplied into the cylinder 12. In this case, the intake air amount becomes smaller than the required amount, and the generated torque becomes smaller than the required torque. Further, for example, when ignition is not performed at an ignition timing set due to, for example, deterioration of the spark plug over time, the combustion efficiency in the cylinder 12 decreases. Therefore, the generated torque is smaller than the required torque. Further, when a specified amount of fuel is not injected due to deterioration of the port injector 36, the generated torque is reduced even if the intake air amount and the ignition timing are controlled as calculated.

  Thus, even if the intake air amount and the ignition timing corresponding to the required torque are calculated based on the torque maps 1 and 2 and controlled to the calculated values, the required torque may not be generated. That is, it can be said that the torque maps 1 and 2 may be shifted due to various factors as described above. Thus, the deviation generated between the required torque and the generated torque is not preferable from the viewpoint of improving drivability and improving the fuel consumption rate. Therefore, when the sensitivity of the torque maps 1 and 2 is shifted, the system of the first embodiment corrects the shift of the torque maps 1 and 2 so as to accurately generate the required torque. Hereinafter, a method of correcting the torque maps 1 and 2 performed by the system of the first embodiment will be described.

[Characteristic control of the system of the first embodiment]
FIG. 4 is a diagram for illustrating the concept of torque control in the first embodiment of the present invention. In FIG. 4, the horizontal axis represents elapsed time, and the vertical axis represents torque. In the case where the required torque (required output) is constant as indicated by the solid line (a) in FIG. 4, the suction is performed so that the torque increases by the torque increase amount X0 (predetermined output) from the intake air amount corresponding to the required torque. When the air amount is increased, the target torque as shown by the solid line (b) can be generated. That is, the torque obtained by increasing the required torque by the torque increase amount X0 is set as the target torque (target output), and the intake air amount (target air amount) corresponding to the target torque is determined according to the torque map 1. Then, a throttle opening control amount X1 (first control amount) is calculated in accordance with the target air amount to control the throttle opening. As a result, there is no deviation in the torque map 1, and if ignition is executed at the ignition timing MBT, the target torque (solid line (b)) is generated.

  The torque increase amount X0 increased by increasing the intake air amount can be offset by retarding the ignition timing from the ignition timing MBT to lower the combustion efficiency and reducing the torque. More specifically, as shown by a solid line (c) in FIG. 4, the target torque in setting the ignition timing is set to a torque smaller than the required torque by a torque down amount X0 (= torque up amount X0). The ignition timing at this time is determined based on the torque map 2 according to the target torque (solid line (c)). In the following embodiment, the ignition timing calculated based on the torque map in accordance with such target torque is referred to as the theoretical timing X2.

  As described above, when the throttle opening is controlled to the control amount 1 and the ignition timing is set to the theoretical time X2, if the torque maps 1 and 2 are not shifted, the amount of increase in the torque by the intake air amount increase control can be obtained. Becomes the torque increase amount X0, and the decrease in torque due to the ignition timing retardation becomes the torque decrease amount X0, which are offset. Therefore, the generated torque matches the required torque (solid line (a)). On the other hand, when there is a deviation in any of the torque maps 1 and 2, the torque up amount due to the increase in the intake air amount and the torque down amount due to the ignition timing retardation are not offset. For example, the dotted line (d) in FIG. As shown in FIG. 5, a torque that deviates from the required torque is generated.

  Here, the deviation between the required torque and the generated torque as described above can be eliminated by adjusting the ignition timing. Specifically, as shown by the dotted line (d) in FIG. 4, when the generated torque is smaller than the required torque, the retard amount of the ignition timing is made smaller than the theoretical timing X2, that is, the theoretical timing. By making the angle of advance more than X2, the generated torque can be matched with the required torque.

  Thus, the control timing X3 (actual control amount) of the ignition timing when the generated torque matches the required torque is to correct the deviation between the generated torque and the required torque that occurs when the control is performed at the theoretical timing X2. is there. Therefore, it is considered that the control timing X3 is obtained by absorbing the deviation generated in the torque map 1 or 2. Accordingly, the torque maps 1 and 2 at the current intake air amount and the engine speed can be corrected according to the actual control timing X3 of the ignition timing.

  More specifically, control is performed according to the following procedure. First, control for map correction is performed in an idle operation state. Further, the load of each auxiliary machine is fixed, that is, in an OFF state or fixed in an ON state. Thereby, the fluctuation | variation of generated torque can be detected as a fluctuation | variation of an engine speed. That is, the deviation between the generated torque and the required torque due to the deviation of the torque maps 1 and 2 can be detected based on the engine speed. In this state, the throttle opening is controlled to control the intake air amount, and the engine speed of the internal combustion engine is maintained at a constant value. The torque map corrected here is a map of the engine speed range at this time.

  In such a state, a target air amount GAtgt with the torque obtained by increasing the required torque by the torque increase amount X0 as a target torque is determined according to the torque map 1, and the control amount X1 of the throttle opening is calculated accordingly. The throttle valve is controlled to gradually increase the opening until the control amount reaches X1. By gradually changing the throttle opening in this way, the intake air amount gradually increases. As a result, the generated torque can be gradually increased from the required torque.

  Along with the control of the throttle opening, the ignition timing is retarded so that the engine speed is always maintained at the speed NEi. That is, even when the throttle opening shifts to the open side control amount X1 and the intake air amount increases, the engine speed is maintained at a constant engine speed NEi corresponding to the required torque. The ignition timing is retarded. In other words, since the load of the auxiliary machinery is kept constant here, the generated torque is kept in agreement with the required torque even when the intake air amount is increased when the engine speed NEi is constant. Can be judged.

  In this state, the control timing X3 of the ignition timing when the intake air amount increases to the target air amount GAtgt is detected. On the other hand, the theoretical timing X2 of the ignition timing is calculated from the torque map 2. In the system according to the first embodiment, all the deviations generated in the torque maps 1 and 2 are absorbed in the torque map 2, and according to the actual control timing X3 or between the theoretical timing X2 and the actual control timing X3. The deviation of the ignition timing torque map 2 is corrected according to the difference.

  FIG. 5 is a diagram for explaining an example of correction of the torque map 2 regarding the ignition timing in the system according to the first embodiment. As a conceptual method of correction, for example, as shown by a two-dot chain line (ii) in FIG. 5, the solid line (i) indicating the torque map 2 is set to the ignition timing with the ignition timing MBT for the required torque fixed. The torque map 2 is corrected by calculating a correction value that is moved in the control timing X3 direction. Alternatively, as indicated by the one-dot chain line (iii) in FIG. 5, the torque map indicated by the solid line (i) is corrected by translating the difference ΔX between the control time X3 and the theoretical time X2. Alternatively, the correction value of the torque map 2 can be calculated by detecting the control timing X3 as described above for a plurality of required torques.

[Specific Control Routine of Embodiment 1]
FIG. 6 is a control routine executed by the ECU 50 as the control device in the first embodiment of the present invention. The routine in FIG. 6 is periodically executed at regular intervals stored in the ECU 50 in advance. In the routine of FIG. 6, first, information on the current operating state such as the current intake air amount GA and the engine speed NE is detected (S102). Next, it is detected whether or not the current operating state satisfies the correction start condition of the torque map 2 (S104). Specifically, it is determined whether conditions such as the current engine warm-up and the catalyst warm-up are completed and normal operation is started, and the current operation state is an idle operation state are satisfied. . If the establishment of the correction start condition is not recognized in step S104, the process returns to step S102 again, and the processes of steps S102 and S104 are repeatedly executed until the establishment of the correction start condition is confirmed.

  On the other hand, if the establishment of the correction start condition is confirmed in step S104, it is next determined whether or not the flag Xnei = OFF corresponding to the current engine speed NEi is set (S106). The flag Xnei is a flag that is turned on when the processing described later is executed and the correction of all the torque maps 2 in the range of the engine speed NEi is completed. Accordingly, when the flag Xnei corresponding to the current engine speed NEi is set to ON, it is unnecessary to correct the torque map 2 of the current speed NEi, and the process returns to step S102 again. The processing in steps S102 to S106 is repeated until the engine speed NEi for which the correction of the torque map 2 relating to the engine speed NEi at that time has not been completed.

  On the other hand, if it is determined in step S106 that Xnei = OFF, it is determined that the correction of the map relating to the rotational speed NEi has not been completed. Therefore, control is performed so that the load of the auxiliary machinery is kept constant (S108). That is, each auxiliary machine is set to the ON state or the OFF state and is maintained as it is during the later-described control.

  Next, the target air amount GAtgt is read (S110). The target air amount GAtgt is stored in the ECU 50 so as to correct the torque map 2 related to the range of the target air amount Gatgt in the current process. Thereafter, the intake air amount is controlled so as to be the target air amount GAtgt (S112). Specifically, a throttle opening target value corresponding to the target air amount GAtgt is set (control amount X1), and the throttle opening is controlled to gradually change toward the control amount X1 of the throttle opening. . That is, a control signal corresponding to the throttle opening control amount X1 from the ECU 50 is transmitted to the actuator 44, whereby the opening of the throttle valve 42 is controlled. At this time, the target air amount GAtgt is set to an intake air amount that generates a target torque that is larger by a torque increase amount X0 than the required torque. Therefore, as the throttle opening gradually changes, the amount of intake air increases so that larger torque can be generated.

  Next, the ignition timing in the process of gradual change of the intake air amount is calculated (S114). The ignition timing is set such that the engine speed is always maintained at NEi by offsetting the torque that increases in the process of change until the intake air amount reaches the target air amount GAtgt. That is, the target torque in determining the ignition timing control amount is set to a torque that is smaller than the required torque by the amount of torque increase due to the increase in intake air amount. Thereafter, the ignition timing is controlled to the ignition timing calculated in step S114, and ignition is performed (S116). The ignition is controlled by issuing a control signal from the ECU 50 to the spark plug actuator 22 at a necessary timing.

  Next, it is determined whether or not the intake air amount has reached the target air amount Gatgt (S118). Specifically, for example, the current intake air amount is detected based on the output of the air flow meter, and the determination is made based on whether or not the intake air amount is equal to or greater than the target air amount GAtgt. In step S118, when it is not recognized that the intake air amount is not less than the target air amount GAtgt, the process returns to S112 again. Control of maintaining the rotational speed NEi by gradually changing the intake air amount and ignition timing control in steps S112 to S118 is repeatedly executed until it is recognized in step S118 that the intake air amount is equal to or greater than the target air amount GAtgt.

  On the other hand, if it is determined in step S118 that the intake air amount is equal to or greater than the target air amount GAtgt, then, after the target air amount GAtgt is exceeded, the engine speed is maintained at that speed NEi for a certain period of time. It is determined whether or not it has been done (S120). When it is not recognized in step S120 that the engine speed is maintained at the speed NEi, the process returns to step S114. Processing such as ignition timing control in steps S114 to S120 is repeatedly performed until the condition in step S120 is satisfied.

  On the other hand, if it is determined in step S120 that the engine speed has been maintained for a certain period, the control timing X3, which is the currently set ignition timing, is detected (S122). Next, in the case of the rotational speed NEi and the intake air amount GAtgt, the theoretical timing X2 of the ignition timing for reducing the required torque by the torque reduction amount X0 is calculated (S124). Thereafter, in accordance with the theoretical timing X2 of the ignition timing and the control timing X3 of the ignition timing, the torque map 2 of the ignition timing within the range of the rotational speed NEi and the intake air amount GAtgt is corrected (S126).

  Next, it is determined whether or not the current target air amount GAtgt is greater than or equal to the maximum intake air amount GAmax set as a torque map (S128). If it is not recognized that the target air amount GAtgt ≧ GAmax, the map is not corrected for the other intake air amount in the range of the rotational speed NEi, so the current target air amount GAtgt is a predetermined amount. The air amount GAtgt + ΔGA increased by ΔGA is reset as the next target air amount GAtgt (S130). Thereafter, the process returns to step S102 again, and the processes of steps S102 to S128 are repeatedly executed for the newly set target air amount GAtgt.

  On the other hand, when it is recognized in step S126 that the target air amount GAtgt ≧ GAmax, the target air amount GAtgt is set to the minimum intake air amount GAmin stored in the ECU 50 in advance (S132). Next, it is determined whether or not the correction of the torque map 2 has been completed for all the rotational speeds NEi set as the torque map 2 (S134). If the completion of the correction of the torque map 2 is not recognized for all the rotational speeds NEi in step S134, the flag Xnei indicating the completion of the correction for the rotational speed NEi corrected this time is turned ON (S136), and again from S102 to S102 The process of S130 is repeatedly executed, and the map relating to the rotational speed NEi that has not been corrected is corrected.

  On the other hand, when the completion of the correction of the torque map 2 regarding all the rotation speeds is recognized, all the flags Xnei for each rotation speed NE range of the torque map 2 are turned OFF (S138), and the current processing is ended.

  As described above, according to the system of the first embodiment, the torque map 2 of the ignition timing can be corrected during the operation of the internal combustion engine 10. Therefore, torque control that follows the required torque more accurately can be performed. Further, when the torque map is corrected, the engine speed is maintained at a constant speed. Therefore, it is possible to perform map correction by performing control accompanied by an increase in the intake air amount and a decrease in combustion efficiency due to a retarded ignition timing while suppressing the occurrence of vibration.

  6, the “first control amount calculation means” of the present invention is realized by executing step S110, and the “first control means” is realized by executing step S112. The “second control means” is realized by executing S118, the “actual control amount detecting means” is realized by executing step S122, and the “second control amount calculation” is executed by executing step S124. "Means" is realized, and "map correction means" is realized by executing step S126.

  By the way, in the system of the first embodiment, an intake pipe 40 and the like are interposed between the downstream side of the throttle valve 42 and the cylinder 12. Therefore, even during the normal operation of the internal combustion engine 10, after the throttle opening is set to the basic throttle opening according to the required torque, the air corresponding to the opening is actually sucked into the cylinder 12 In the meantime, a delay due to the volume of the intake pipe 40 occurs. For this reason, when the required torque changes abruptly, there is a case where the intake of the intake air amount necessary for generating the required torque is not in time and a response delay occurs.

  FIG. 7 shows an example in which torque according to the required torque is generated by combining control of the throttle opening and control of the ignition timing. Specifically, in the example shown in FIG. 7, the fluctuation of the required torque is predicted in advance according to the accelerator opening or the like. For example, when a sudden increase in the required torque (a) is predicted to some extent before at time T1, the throttle opening is immediately controlled to open. Thereby, the increase in the intake air amount can be started at an earlier stage. The upper limit torque, which is the maximum value of the torque that can be output in this state, is the predicted required torque (solid line (solid line (b)) before the required torque suddenly increases, as represented by a one-dot chain line (b) in FIG. It is bigger than a)).

  Here, the upper limit torque (b) is the maximum value of torque that can be generated when the throttle opening is fully opened, and this ignition timing is controlled to MBT. Therefore, by actually retarding the ignition timing from the MBT, the actually generated torque can be made lower than the upper limit torque. In other words, if control is performed to retard the ignition timing from the MBT so as to reduce the torque indicated by the arrow (c) according to the required torque, the generated torque is reduced to the required torque (a) as indicated by the dotted line (d). The torque can be adapted to

  Thus, in the actual control of the internal combustion engine 10, the control amounts of both are determined based on the torque map 1 related to the intake air amount and the torque map 2 related to the ignition timing. It may be controlled. In such a case, correction of the torque map by the system of the first embodiment is particularly effective, and more accurate output control is performed by correcting one or both maps in the relationship between the intake air amount and the ignition timing. be able to. The same applies to the following embodiments.

  In the system of the first embodiment, the case where only the torque map 2 is corrected has been described from the control timing X3 of the ignition timing or from the relationship between the theoretical timing X2 and the control timing X3. However, the deviation that occurs between the control timing X3 of the ignition timing and the theoretical timing X2 is not necessarily caused only by the deviation of the torque map 2, but may be caused by the deviation of the torque map 1. Therefore, for example, a correction value for each torque map may be calculated from the control timing X3 of the ignition timing and the theoretical timing X2, and either or both of the torque maps 1 and 2 may be corrected. The same applies to the following embodiments.

  Further, in the system of the first embodiment, the torque map is corrected by controlling the torque to be constant by making the load of the auxiliary machinery constant in the idling state and making the engine speed constant. Explained. However, the parameter for controlling the output of the internal combustion engine 10 is not limited to the engine speed. For example, the vehicle speed may be kept constant under certain driving conditions, or the torque may be directly detected and controlled. The same applies to the following embodiments.

  Moreover, in the system of Embodiment 1, the case where the control for torque map correction | amendment was performed only in the case of an idle driving | running state was demonstrated. However, the present invention is not limited to this, and the same control as described above can be performed during normal traveling as long as the required torque can be maintained within a certain range. However, in this case, it is necessary to keep the load constant. For example, it is understood that the load on the uphill road is not abruptly fluctuated due to, for example, navigation information, changes in vehicle speed or accelerator opening, etc. In this state, it is desirable to execute map correction control.

  Further, the system according to the first embodiment has been described for the case where the output of the internal combustion engine 10 is made constant by controlling the opening degree of the throttle valve 42 and controlling the ignition timing, and the torque maps 1 and 2 of both are corrected. However, the present invention is not limited to this, and can be applied to a combination of two control means for controlling the output of the internal combustion engine 10 to be a required output. Specifically, for example, the output of the internal combustion engine 10 is controlled by controlling the intake air amount by controlling the opening of the throttle valve 32 and the intake and exhaust valves 26 and 30, or the intake and exhaust valves 26, It is also effective to apply the control to the amount of intake air by 30 and the control of the output of the internal combustion engine 10 by controlling the ignition timing. In particular, when using two control means having different responsiveness in the output control of the internal combustion engine 10, more accurate output control may be realized. Therefore, the correction of the map used in such a case by the method of the system of the first embodiment is effective. The same applies to the following embodiments.

  In the system of the first embodiment, the torque increase amount X0 is increased by controlling the throttle opening, and thereafter the ignition timing control timing X3 in a state where the engine speed is maintained is detected. The case where the map is corrected based on the above has been described. However, the torque map correction method is not limited to this in the present invention. For example, the torque increase amount X0 is increased by controlling the throttle opening, and thereafter, from the torque map 2 regarding the ignition timing, the theoretical timing X2 of the ignition timing for generating a target torque that reduces the torque by X0 from the required torque. And the ignition timing is controlled based on this theoretical timing X2. The resulting torque or engine speed is detected. The torque map 1 and the torque map 2 can also be corrected based on the difference between the detected value and the required torque, or the difference between the detected engine speed and the corresponding engine speed. The same applies to the following embodiments.

  In the control in this case, the “first control amount calculating means” of the present invention is realized by calculating the throttle opening, and the “first control means” is realized by controlling the throttle opening. Then, the “second control amount calculation means” is realized by calculating the theoretical time X2, and the “actual output detection means” is realized by detecting the generated torque or the engine speed, and the torque map is accordingly obtained. By correcting the above, a “map correction unit” is realized.

Embodiment 2. FIG.
The system configuration of the second embodiment is the same as the system of the first embodiment. The system of the second embodiment also corrects the torque map 2 related to the ignition timing in the same way as the system of the first embodiment. However, the control by the system of the second embodiment corrects the torque map 2 during normal operation of the internal combustion engine. This is different from the control of the system in the first embodiment.

  Specifically, in the first embodiment, the engine speed is controlled while idling and the load is all constant, and the ignition timing control timing X3 is detected to obtain a map correction value. Explained the case. However, when the torque map is corrected in a transient state where the required torque varies using the same method, the difference between the detected ignition timing X3 and the theoretical timing X2 theoretically determined from the torque map 2 is In addition to the deviation of the torque maps 1 and 2, there may be a difference caused by deviations in various torque controls such as a response delay in torque control. Accordingly, when the control in the first embodiment is applied in a state where the required torque varies, the correction based on the control timing X3 may not necessarily correct the torque map accurately. For this reason, the system of the second embodiment performs the following control during normal operation in which the required torque varies.

  FIG. 8 is a diagram for explaining fluctuations in required torque when performing map correction control in the system of the second embodiment and fluctuations in target torque due to an increase in intake air amount. It is a figure for demonstrating the relationship between the request torque at the time of performing control of map correction | amendment in the system of the form 2, and generated torque. 8 and 9, the horizontal axis represents time, and the vertical axis represents torque.

  In the operating state in which the required torque varies, the system according to the second embodiment predicts the required torque as shown by the solid line (a) in FIG. 8 until a certain period ahead according to the amount of operation of the accelerator opening. To do. Here, the target torque due to the increase in the intake air amount is a torque obtained by adding a periodically varying torque Y0 that varies in the period T to the predicted required torque, as shown by a solid line (b) in FIG.

  At this time, the theoretical timing Y2 of the ignition timing is obtained according to the torque map 2 with the target torque reduced by the period variation torque Y0. Specifically, the theoretical timing Y2 is a timing obtained by retarding the basic ignition timing MBT by the cycle T according to the cycle variation torque Y0. If there is no deviation in the torque maps 1 and 2, if the ignition timing is controlled to the theoretical timing Y2, the period fluctuation torque Y0 that fluctuates in the period T is canceled out. In other words, the difference between the required torque and the generated torque includes a shift in torque control. However, in the state where there is no shift in the torque maps 1 and 2, at least the difference between the required torque and the generated torque. Is considered to have no fluctuation component of period T.

  On the other hand, when the torque maps 1 and 2 are misaligned, even if the ignition timing is controlled to the theoretical timing Y2, as shown by the dotted line (b) in FIG. It becomes. When the control based on the ignition timing is performed so that the period fluctuation component disappears, the control timing Y3 of the ignition timing is different from the theoretical timing Y2.

  FIG. 10 is a diagram for explaining the ignition timing retardation amount necessary for canceling the cycle variation torque Y0 due to the increase of the intake air amount in the control of the system of the second embodiment. In FIG. 10, the horizontal axis represents time, and the vertical axis represents the ignition timing retardation amount. Note that the vertical axis represents the ignition timing MBT as a reference, and the retard side is expressed as a negative value.

  As described above, if there is no deviation in the torque maps 1 and 2, the retard amount of the theoretical timing Y2 of the ignition timing with respect to the ignition timing MBT is to perform torque reduction according to the cycle variation torque Y0. As shown by the solid line (Y2) in FIG. 10, the amount of retardation is a predetermined amplitude that changes with the period T. On the other hand, when torque control is performed so that the torque maps 1 and 2 are deviated and the cyclic fluctuation component generated in the generated torque is removed, the amplitude of the ignition timing retardation amount is calculated theoretically as indicated by the dotted line (Y3). It differs from the amplitude of time Y2.

  Therefore, in the system of the second embodiment, the intake air amount is controlled with the target air amount GAtgt corresponding to the target torque obtained by adding the cycle variation torque Y0 to the required torque, and the generated torque is generated by retarding the ignition timing. Control is performed so as to eliminate the periodic fluctuation component generated in. A component that varies at the cycle T is extracted from the control timing Y3 of the ignition timing at this time, and a correction value for the torque map is calculated by obtaining a difference from the component that varies at the cycle T of the theoretical timing Y2, and the torque map 2 Correct.

  In the system according to the second embodiment, the load on each auxiliary machine is kept constant during torque map correction control. Accordingly, the engine speed changes in the same manner as the torque fluctuation. Also in the control of the second embodiment, the fluctuation of the generated torque is monitored by the rotation speed, and the determination of whether or not the generated torque includes a periodic fluctuation component is also based on the fluctuation of the engine rotation speed. To do.

  Whether or not the period variation component included in the engine speed in the generated torque has disappeared can be determined by, for example, passing the detected engine speed waveform through a high-pass filter. Specifically, by passing through the high-pass filter, only the high frequency periodic fluctuation component included in the engine speed is extracted. Therefore, if a periodic fluctuation component is detected from the waveform of the engine speed when passing through the high-pass filter, it is determined that the cyclic fluctuation component of the generated torque has not yet disappeared. Similarly, by passing the waveform of the control timing Y3 of the ignition timing through a high-pass filter, only the periodic retard control amount included in the control timing Y3 can be extracted. Therefore, the correction value of the torque map can be calculated based on the waveform of the control time Y3 that has passed through the high-pass filter.

  As described above, according to the system of the second embodiment, even when the required torque fluctuates, the torque maps 1 and 2 can be shifted by setting the torque increase amount due to the increase of the intake air amount to the periodic variation torque Y0. The deviation generated in the ignition timing control timing Y3 can be extracted as a periodic component. Accordingly, it is possible to correct the torque map more accurately by removing the influence of other deviations in the torque control when the required torque fluctuates.

  FIG. 11 is a control routine executed by the ECU 50 in the second embodiment of the present invention. The routine in FIG. 11 is a routine that is periodically executed at regular intervals. In the routine of FIG. 11, as in the routine of FIG. 6, after information related to the operating state of the internal combustion engine is detected, the map correction start condition is satisfied, and the load on the auxiliary machinery is fixed (S 202-). In step S206, the required torque from the present time to a certain time ahead is predicted according to the change in the accelerator opening (S208).

  Next, the target torque is calculated (S210). The target torque is calculated by adding the cyclic fluctuation torque Y0 stored in advance in the ECU 50 to the target torque calculated in step S208. Next, the target air amount GAtgt is set (S212). The target air amount GAtgt is set as an air amount that realizes the target torque at the current engine speed according to the torque map 1 related to the intake air amount.

  Next, the throttle opening is calculated according to the target air amount GAtgt, and the throttle valve 42 is controlled to the calculated throttle opening (S214). Next, the ignition timing is calculated (S216) and controlled according to the calculated ignition timing (S218). The ignition timing is set and controlled so that the generated torque becomes the required torque when the intake air amount changes along the target air amount GAtgt by controlling the throttle opening. More specifically, the engine speed NE is monitored and controlled so as to be the engine speed corresponding to the required torque.

  Next, it is determined whether or not the cyclic fluctuation component has disappeared from the waveform of fluctuations in the engine speed during a certain period until now (S220). Specifically, the waveform extracted when the waveform of the engine speed during a certain period up to the present time is passed through the high-pass filter includes a waveform with a period T greater than the amplitude of the allowable range (reference value). It is determined based on whether or not it can be determined. If it is determined in step S220 that the cyclic fluctuation component has not disappeared, the cyclic fluctuation torque Y0 is not canceled out by the ignition timing control, and therefore the processes of steps S208 to S218 are performed again. Thereafter, in step S220, it is determined again whether or not the periodic fluctuation component of the engine speed has disappeared. Such processing in steps S208 to S220 is repeatedly executed until the disappearance of the periodic variation component is recognized in step S220.

  On the other hand, if it is determined in step S220 that the cyclic variation component has disappeared from the engine speed waveform, the control timing Y3 of the ignition timing during a certain period until now is detected (S222). Next, the theoretical timing Y2 of the ignition timing for canceling the cycle variation torque Y0 is calculated (S224).

  Thereafter, the torque map 2 is corrected based on the actual control timing Y3 and the theoretical timing Y2 of the ignition timing (S226). Specifically, the fluctuation component of the cycle T included in the control timing Y3 is extracted as the retardation amount in the actual control, and this retardation amount and the retardation amount corresponding to the periodic variation torque Y0 included in the theoretical timing Y2 The torque map 2 is corrected based on the difference. In this routine, since the correction value of the torque map is calculated in an environment where the required torque fluctuates, the correction value obtained this time is reflected in the entire torque map 2 relating to the ignition timing and corrected. However, the present invention is not limited to this correction method. For example, the above control is repeated by correcting only the torque map 2 related to the range of engine speed and the range of intake air amount changed during the current map correction control. Thus, the torque map in the other engine speed range and intake air amount range may be corrected. Alternatively, the average value of the engine speed and the intake air amount may be obtained, and only the torque map 2 related to the average value may be corrected, and the above processing may be repeated to correct the torque map.

  In the second embodiment, by executing step S212, the “first control amount calculating means” of the present invention is realized, and by executing step S214, the “first control means” is realized, By executing steps S216 to S218, a “second control unit” is realized, and by executing step S220, a “periodic variation determination unit” is realized, and by executing step S222, an “actual control amount” is realized. The “detection means” is realized, and the “second control amount calculation means” is realized by executing step S224, and the “map correction means” is realized by executing step S226.

  In the above embodiment, when referring to the number of each element, quantity, quantity, range, etc., unless otherwise specified or clearly specified in principle, the number referred to It is not limited. Further, the structure, steps in the method, and the like described in the present embodiment are not necessarily essential to the present invention unless otherwise specified or clearly specified in principle.

It is a schematic diagram for demonstrating the structure of the system in Embodiment 1 of this invention. It is a figure for demonstrating the relationship between the amount of intake air, and the generated torque. It is a figure for demonstrating the relationship between ignition timing and the torque which generate | occur | produces. It is a figure for demonstrating an example of the generated torque by control of intake air amount and ignition timing. It is a figure for demonstrating correction | amendment of the map which shows the relationship between ignition timing and the torque which generate | occur | produces. It is a flowchart for demonstrating the control routine which ECU performs in Embodiment 1 of this invention. It is a figure for demonstrating the other example of the torque control by Embodiment 1 of this invention by control of intake air amount and ignition timing. It is a figure for demonstrating the relationship between the request torque in Embodiment 2 of this invention, and the target torque by intake air amount control. It is a figure for demonstrating the theoretical value of the ignition timing retard amount in Embodiment 2 of this invention. It is a figure for demonstrating the required torque in Embodiment 2 of this invention, and the generated torque by control of intake air amount and ignition timing. It is a flowchart for demonstrating the routine of control which ECU performs in Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Internal combustion engine 12 Cylinder 16 Rotational speed sensor 20 Spark plug 22 Actuator 24 Intake port 26 Intake valve 28 Exhaust port 30 Exhaust valve 32, 34 Variable valve mechanism 36 Port injector 40 Intake passage 42 Throttle valve 44 Actuator 46 Air flow meter 50 ECU
52 Accelerator position sensor

Claims (6)

First output changing means for changing the output of the internal combustion engine;
Second output changing means for changing the output with responsiveness different from that of the first control means;
A control device for controlling an internal combustion engine comprising:
In an operating state where the required output required for the internal combustion engine is constant, target output setting means for setting a target output different from the required output by a constant output;
An output of the internal combustion engine, according to a first map defining a relationship between the control amount of the first output changing means, wherein as the output of the internal combustion engine becomes the target output, a first control to said first output changing means First control amount calculating means for calculating an amount;
First control means for controlling the first output changing means to the first control amount;
Second control means for controlling the second output change means so that the internal combustion engine emits the required output in a state where the first output change means is controlled to the first control amount;
An actual control amount detecting means for detecting an actual control amount that is an actual control amount for the second output changing means by the second control means;
According to a second map defining a relationship between the control amount of the second output changing means and the control amount of the output and the first output changing means before SL internal combustion engine, said first output changing means is controlled by the first control amount A second control amount calculating means for calculating a second control amount for the second output changing means so that the output of the internal combustion engine becomes the required output in the state where
Map correction means for correcting the first map and / or the second map according to a difference between the actual control amount and the second control amount ;
A control device for an internal combustion engine, comprising: First output changing means for changing the output of the internal combustion engine;
Second output changing means for changing the output with responsiveness different from that of the first control means;
A control device for controlling an internal combustion engine comprising:
Target output setting means for setting a target output obtained by adding a periodic fluctuation output in which the output changes at a constant cycle to the required output required for the internal combustion engine ;
A first control for the first output changing means such that the output of the internal combustion engine becomes the target output according to a first map that defines the relationship between the output of the internal combustion engine and the control amount of the first output changing means. First control amount calculating means for calculating an amount;
First control means for controlling the first output changing means to the first control amount;
Second control means for controlling the second output change means so that the internal combustion engine emits the required output in a state where the first output change means is controlled to the first control amount;
In a state where the first output changing means is controlled to the first control amount and the second output changing means is controlled by the second control means, the cycle fluctuation of the output generated by the internal combustion engine is below a reference value. Periodic fluctuation determining means for determining the disappearance of the periodic fluctuation when
In a state in which extinction was observed before SL period fluctuations, the actual control quantity for said second output changing means, and the actual control amount detecting means for detecting the actual controlled variable,
The first output change means is controlled to the first control amount according to a second map that defines the relationship among the output of the internal combustion engine, the control amount of the first output change means, and the control amount of the second output change means. A second controlled variable calculating means for calculating a second controlled variable for the second output changing means so that the output of the internal combustion engine becomes the required output in the
Map correction means for correcting the first map and / or the second map according to a difference between the actual control amount and the second control amount;
A control device for an internal combustion engine, comprising: The control apparatus for an internal combustion engine according to claim 1 or 2 , wherein the output of the internal combustion engine is controlled by using the rotational speed of the internal combustion engine as a parameter. The first output changing means is a throttle valve disposed in an intake passage of the internal combustion engine,
The control device for an internal combustion engine according to any one of claims 1 to 3, wherein the first control means controls an opening of the throttle valve. The second output changing means is an internal combustion engine ignition device,
Said second control means is a control apparatus for an internal combustion engine according to claim 1, any one of 4, characterized in that to control the timing of ignition by the ignition device. First output changing means for changing the output of the internal combustion engine;
Wherein a different response from the first output changing means, a control apparatus for an internal combustion engine and a second output change hands stage for changing the output,
In an operating state where the required output required for the internal combustion engine is constant, target output setting means for setting a target output different from the required output by a constant output;
An output of the internal combustion engine, according to a first map defining a relationship between the control amount for said first output changing means, wherein as the output of the internal combustion engine becomes the target output, a first control to said first output changing means First control amount calculating means for calculating an amount;
The first output change means is controlled to the first control amount according to a second map that defines the relationship among the output of the internal combustion engine, the control amount of the first output change means, and the control amount of the second output change means. If that, the second control amount calculation means for calculating a second control amount with respect to the like outputs of the internal combustion engine becomes the required output, the second output changing means,
First control means for controlling the first output changing means to the first control amount;
Second control means for controlling the second output changing means to the second control amount;
An actual output detecting means for detecting an actual output of the internal combustion engine in a state where the first output changing means is controlled to the first control amount and the second output changing means is controlled to the second control amount;
Map correction means for correcting the first map and / or the second map according to a difference between the target output and the actual output;
A control device for an internal combustion engine, comprising:

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