JP2021017858A - Engine controller - Google Patents

Abstract

To provide an engine controller capable of improving acceleration responsiveness upon changing gears, in an automatic transmission vehicle equipped with a turbocharger with a movable vane.SOLUTION: An engine controller comprises a turbocharger 30 with a movable vane 33 and an ECU 40 that can execute torque down control based on a shift command signal of an automatic transmission 20. The ECU 40 controls a closing amount of the movable vane 33 based on a first opening characteristic map M1 set so that the opening becomes large when the energy of exhaust gas is large, and while a closing request signal is being output for a period that starts from the time when an operation delay time of the movable vane 33 is earlier than inertia phase start timing of the automatic transmission 20 and ends at the time when the operation delay time of the movable vane 33 is earlier than inertia phase end timing, controls the closing amount of the movable vane 33 based on a second opening characteristic map M2, which has a larger closing amount than the first opening characteristic map M1.SELECTED DRAWING: Figure 1

Description

The present invention relates to an engine control device, in particular, an engine control device including a turbocharger with a movable vane and a control means capable of executing torque down control for reducing a fuel injection amount based on a shift command signal. Regarding.

Conventionally, in a manual transmission vehicle equipped with a turbocharger, the flow rate of exhaust gas supplied to the turbine is reduced by the occupant's stepping-back operation of the accelerator pedal during shifting, so that the rotation speed of the turbine and compressor is reduced. It is known that even if the accelerator pedal is depressed again, a so-called turbo lag occurs, in which it takes a long time for the boost pressure to rise and recover.
As one of the effective technologies for improving the decrease in acceleration response caused by this turbo lag, there is a variable geometry turbocharger (VGT) with a movable vane.

The turbocharger control device of Patent Document 1 includes a variable vane that can adjust the flow rate of exhaust gas supplied to the turbine, detects the shift-up state of the automatic transmission, and sets the opening degree of the variable vane to the closed side. At the same time as increasing the exhaust pressure of the exhaust system, the engine speed is reduced while supercharging during the shift, and the opening of the variable vane is set to the open side when the shift up is completed.
As a result, at the start of shift-up, the closing amount of the variable vane is increased to increase the flow velocity of the exhaust gas and increase the rotational speed of the turbine to secure the exhaust gas energy.
Further, when the shift-up is completed, the exhaust resistance increase is eliminated while suppressing an excessive increase in the rotational speed of the turbine by reducing the closing amount of the variable vane.

Japanese Unexamined Patent Publication No. 10-331650

The turbocharger control device of Patent Document 1 improves the acceleration response due to the turbo lag by increasing the flow velocity of the exhaust gas and increasing the rotation speed of the turbine at the time of shifting.
However, in the technique of Patent Document 1, there is a possibility that sufficient acceleration responsiveness cannot be ensured when the occupant depresses the accelerator pedal again at the time of shifting.

As shown in FIG. 8, in an automatic speed change vehicle equipped with a VGT, when the accelerator pedal is continuously depressed, the running speed of the vehicle continuously increases, and the high speed stage is based on a predetermined speed change map set in advance. Shift up to (power on up shift) is executed continuously.
For example, when the shift switching line of the shift map is crossed at time t1, the shift control unit outputs a shift command signal between time t1 and time t7. Further, the shift control unit calculates the inertia phase start timing, time t3, and the inertia phase end timing, time t5, at the same time as the output of the shift command signal. Then, during the inertia phase (time t3 to time t5), in order to synchronize the engine speed and the friction fastening element speed, the shift control unit outputs a torque down request signal, and the engine matches the torque down request signal. The fuel injection amount is reduced to reduce the speed change torque.

On the other hand, the movable vane in the turbine chamber is controlled to decrease its target opening during the inertia phase of the automatic transmission, and then returns the target opening to a predetermined reference opening at time t6.
Since the rotational speed of the turbine is linked to the closing amount of the movable vane, the actual boost pressure of the intake air supplied to the combustion chamber of the engine is reduced in a tendency substantially similar to the target opening degree of the movable vane.
The movable vane is controlled to the closed side from the first half of the inertia phase when the engine speed is high, but the exhaust pressure does not rise sharply due to the delay in the closing operation response.

As described above, during the power-on-up shift, the actual boost pressure drops in response to the torque down request signal after the shift torque down starts, so that the occupant can perform the shift torque down or immediately after the shift torque down. Even if the accelerator pedal is depressed, the vehicle cannot physically accelerate until the actual boost pressure increases and the target boost pressure is reached.
That is, the technique of Patent Document 1 is not sufficient with respect to the acceleration responsiveness in the upshift of the automatic transmission, and there is room for further improvement.

An object of the present invention is to provide an engine control device or the like capable of improving acceleration response during shifting.

The engine control device according to claim 1 is a turbocharger with a movable vane whose opening degree can be adjusted in order to change the flow path area of the exhaust gas supplied to the turbine, and an automatic switchable gear stage. In an engine control device including a control means capable of executing torque down control for reducing a fuel injection amount based on a shift command signal of a transmission, the control means is said to be exhaust gas when the energy of the exhaust gas is large. Basic vane control for controlling the closing amount of the movable vane is performed based on the first opening characteristic set so that the opening degree of the movable vane is larger than when the energy of the movable vane is small, and the shift command signal At the time of output, it is characterized in that coordinated vane control for controlling the closing amount of the movable vane is performed based on the second opening characteristic set so that the closing amount is larger than the first opening characteristic.

In the control device of this engine, the control means has a first opening characteristic set so that when the energy of the exhaust gas is large, the opening degree of the movable vane is larger than when the energy of the exhaust gas is small. Since the basic vane control for controlling the closing amount of the movable vane is performed based on the above, when the energy of the exhaust gas is small, the flow velocity of the exhaust gas is increased by increasing the closing amount of the variable vane to increase the rotation speed of the turbine. As a result, the exhaust gas energy can be secured, and even when the exhaust gas energy is small, it can be accelerated in response to the operation of the accelerator pedal being depressed by the occupant. In addition, when the energy of the exhaust gas is large, the flow velocity of the exhaust gas is slowed down by reducing the closing amount of the variable vane, and the exhaust pressure is lowered by lowering the rotation speed of the turbine to improve fuel efficiency and output. Can be done.
The control means is a coordinated vane control that controls the closing amount of the movable vane based on the second opening characteristic set so that the closing amount is larger than the first opening characteristic when the shift command signal is output. Therefore, it is possible to suppress a decrease in the actual boost pressure during shifting, and when the occupant depresses the accelerator pedal during shifting, the time required for the actual boost pressure to return to the target boost pressure is shortened. Can be transformed into.

According to a second aspect of the present invention, in the first aspect of the present invention, when the control means outputs the shift command signal, the operation delay time of the movable vane is earlier than the predicted start timing of the inertia phase of the automatic transmission. While the closing request signal is generated and the closing request signal is output at a time earlier than the operation delay time of the movable vane of the automatic transmission, which is predicted to start from the above. It is characterized by performing cooperative vane control.
According to this configuration, the increase in exhaust gas energy due to the increase in the closing amount of the movable vane can be started in consideration of the time constant delay related to the structural inertia of the movable vane, and the decrease in the actual boost pressure can be suppressed and accelerated. The responsiveness can be further enhanced.

The invention of claim 3 is characterized in that, in the invention of claim 2, the control means reduces the closing amount of the movable vane as the engine torque increases while the closing request signal is output.
According to this configuration, it is possible to increase the exhaust gas energy while suppressing the increase in the exhaust pressure due to the increase in the engine torque.

The invention of claim 4 is characterized in that, in the invention of claim 2, the control means reduces the closing amount of the movable vane as the engine speed increases while the closing request signal is output. ..
According to this configuration, the exhaust gas energy can be increased while suppressing the increase in the exhaust pressure due to the increase in the engine speed.

The invention of claim 5 is the invention of any one of claims 2 to 4, wherein the control means said the movable vane when a decrease in engine torque was started while the closing request signal was being output. It is characterized by increasing the closing amount of.
According to this configuration, the exhaust gas energy can be increased in synchronization with the decrease in engine torque.

The invention of claim 6 is the invention of any one of claims 2 to 4, wherein the control means is movable when the engine speed starts to decrease while the closing request signal is being output. It is characterized by increasing the amount of vane closure.
According to this configuration, the exhaust gas energy can be increased in synchronization with the decrease in the engine speed.

The invention of claim 7 is the invention of any one of claims 1 to 6, wherein the control means has first and second control maps in which the first and second opening characteristics are set, respectively. It is characterized in that the closing amount of the movable vane is controlled based on the first and second control maps.
According to this configuration, it is possible to simplify the configuration of the closing amount control of the movable vane during shifting and non-shifting.

According to the engine control device of the present invention, it is possible to improve the acceleration responsiveness at the time of shifting in an automatic transmission vehicle equipped with a turbocharger with a movable vane.

It is a schematic block diagram of the engine which concerns on Example 1. FIG. It is a vertical sectional view of the turbine chamber of a turbocharger. It is a time chart which shows the change mode of each element at the time of a shift. It is a figure which shows the 1st opening degree characteristic map. It is a figure which shows the 2nd opening degree characteristic map. It is a flowchart which shows the vane control processing procedure. It is a time chart which shows the change mode of the closing request signal and the target opening degree which concerns on a modification. It is a time chart which shows the change mode of each element at the time of shifting which concerns on a prior art.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The following description of preferred embodiments is merely exemplary and is not intended to limit the invention, its applications or its uses.

Hereinafter, Example 1 of the present invention will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the engine system S according to the first embodiment controls, for example, the engine 1 as a 6-cylinder diesel engine, the automatic transmission 20, the turbocharger 30, and the engine system S. The main components are an ECU (Electronic Control Unit) 40 (control means), various sensors 51 to 56, and the like.

First, the engine 1 will be described.
As shown in FIG. 1, the engine 1 is provided with fuel injection valves 3 for supplying fuel to the combustion chamber 2 for each cylinder. Each fuel injection valve 3 is connected to a common rail (not shown) via a distribution passage. The common rail stores the fuel pumped from the fuel pump (not shown) in a state of being accumulated. The cylinder of each cylinder is provided with a rotation speed sensor 51 capable of detecting the rotation speed (rpm) of the engine 1. Further, the engine 1 includes intake / exhaust ports 1a and 1b communicated with the combustion chamber 2, an intake passage 4 connected to the intake port 1a, an exhaust passage 5 connected to the exhaust port 1b, an intake passage 4 and an exhaust. It is provided with an EGR passage 6 or the like that communicates with the passage 5.

In the intake passage 4, an air flow sensor 52, a compressor 32 of a turbocharger 30, a throttle valve 7, an intercooler 8, a surge tank 9, and the like are arranged in this order from the upstream side. The surge tank 9 is provided with an intake pressure sensor 53.
The exhaust passage 5 is provided with a turbine 31 of the turbocharger 30 and a catalyst (not shown) arranged at a position downstream of the turbine 31. An exhaust pressure sensor 54 for detecting the exhaust pressure is arranged at a position on the upstream side of the turbine 31. An EGR valve 10 is arranged in the middle of the EGR passage 6. The EGR valve 10 is operated to be partially opened or fully opened via a duty-controllable solenoid valve (not shown) at least in a low rotation and low load region.

Next, the automatic transmission 20 will be described.
As shown in FIG. 1, the automatic transmission 20 is connected to the engine 1 via a starting device (not shown). The automatic transmission 20 is driven by shifting the rotation speed of the crankshaft 11 to a desired rotation speed by forming a forward traveling gear stage (for example, 1st to 6th speeds in the D range) and a reverse traveling gear stage. It is transmitted to the ring (not shown). It should be noted that the number of forward traveling gears may be a plurality of gears, and the number of forward traveling gears is not limited to the 1st to 6th gears.

Next, the turbocharger 30 will be described.
The turbocharger 30 is compactly configured so that the intake air supplied to the combustion chamber 2 can be efficiently supercharged even when the exhaust gas energy is low (low rotation region or low load region).
Further, the turbocharger 30 is provided with a plurality of movable vanes 33 so as to surround the entire circumference of the turbine 31, and the capacity capable of changing the flow path area of the exhaust gas toward the turbine 31 by these plurality of movable vanes 33. It constitutes a variable-type turbocharger (VGT).

As shown in FIG. 2, in the turbine chamber 34 formed in the turbine casing, a plurality of movable vanes 33 are arranged so as to surround the periphery of the turbine 31 arranged at a substantially central portion. Each movable vane 33 is rotatably supported by a support shaft 35 penetrating one side wall of the turbine chamber 34. When each movable vane 33 rotates clockwise around a support shaft 35 and is inclined so as to be close to each other, the opening degree (flow path area) formed between the movable vanes 33 is narrowed down to a small size. , High supercharging efficiency can be obtained even when the exhaust gas flow rate is small. On the other hand, if each movable vane 33 is rotated counterclockwise and tilted so as to be separated from each other, the opening degree is increased, so that the exhaust resistance is reduced even when the exhaust gas flow rate is large. , The supercharging efficiency can be increased.

The ring member 36 is driven and connected to the rod 39 of the actuator 38 (see FIG. 1) via the link mechanism 37, and each movable vane 33 is rotated via the ring member 36 by the operation of the actuator 38. The link mechanism 37 includes a connecting pin 37a whose one end is rotatably connected to the ring member 36, and a connecting plate member 37b whose one end is rotatably connected to the other end of the connecting pin 37a. A columnar member 37c connected to the other end of the connecting plate member 37b and penetrating the outer wall of the turbine casing, and a connecting plate member 37d having one end connected to a protruding end of the columnar member 37c protruding out of the turbine casing. The other end of the connecting plate member 37d is rotatably connected to the rod 39 by a connecting pin (not shown).

Next, the ECU 40 will be described.
The ECU 40 is composed of a central arithmetic processing unit that executes various programs, a memory (RAM, ROM), an input / output bus, and the like. As shown in FIG. 1, the ECU 40 has a fuel control unit 41, a shift control unit 42, a vane control unit 43, and the like as main components.

First, the fuel control unit 41 will be described.
The fuel control unit 41 has a target torque map (1) set in advance based on the opening degree (%) of the accelerator pedal (not shown) detected by the accelerator opening degree sensor 55 and the engine rotation speed detected by the rotation speed sensor 51. The target torque of the engine is read out via the target torque (not shown), and the target fuel injection amount map (not shown) set in advance based on the target torque, the engine rotation speed, and the actual fresh air amount detected by the airflow sensor 52 is used. The target fuel injection amount is read out. Then, the fuel control unit 41 controls the fuel injection amount to be supplied to the combustion chamber 2 by adjusting the excitation time of the fuel injection valve 3 based on the set target fuel injection amount and the fuel pressure in the common rail. There is.

The fuel control unit 41 sets the fuel correction amount based on the torque down request signal (see FIG. 3) output from the shift control unit 42 at the time of shifting, and reduces the fuel correction amount from the target fuel injection amount.
Therefore, as shown in FIG. 3, the fuel control unit 41 sharply reduces the fuel injection amount at the inertia phase start timing (time t3) to start the shift torque reduction, and shifts at the inertia phase end timing (time t5). By ending the torque down, the engine speed and the friction fastening element speed are synchronized.

Next, the shift control unit 42 will be described.
The shift control unit 42 determines the traveling speed of the vehicle detected by the vehicle speed sensor 56 and the accelerator opening degree detected by the accelerator opening sensor 55 for each traveling range selected by the operation of the shift lever (not shown) by the occupant. Based on this, the gear stage to be switched is read out via a preset shift map (not shown), and the shifting solenoid valve (not shown) is controlled on and off. Then, the shift control unit 42 switches the spool position of each shift valve via the shift solenoid valve, and fastens each friction fastening element so as to be a combination for each gear stage.

Further, the shift control unit 42 predicts and calculates the inertia phase at the same time as the shift starts.
The inertia phase is one of the phases (phases) that occur during the progress of shifting, and is a phase in which the transmission input rotation speed changes mainly due to the inertia change of the drive system. Therefore, normally, in the torque phase at the initial stage of shifting, the engine speed changes according to the accelerator operation, and in the inertia phase at the latter stage of shifting, the engine speed changes due to shifting.

As shown in FIG. 3, when the traveling state of the vehicle is a power-on-up shift that crosses a shift switching line on the shift map, for example, a shift switching line that switches from 5th gear to 6th gear while maintaining the accelerator depressed state, shift control is performed. The unit 42 generates a shift command signal and a torque down request signal, and outputs the shift command signal and the torque down request signal to the fuel control unit 41, respectively.
The shift command signal is output at time t1 when the traveling state of the vehicle crosses the shift switching line on the shift map, and a predetermined time required for completing the operation of the peripheral elements has elapsed from the actual shift end time t5, which is the inertia phase end timing. Output is stopped at time t7. The torque down request signal is output at the actual shift start time t3, which is the inertia phase start timing, and is reduced from a predetermined time before the actual shift end time so that the output is stopped at the actual shift end time t5.

The shift control unit 42 generates a dedicated closing request signal for controlling the movable vane 33 at the time of shifting, and outputs this closing request signal to the vane control unit 43. The output level of this closing request signal corresponds to the required torque calculation value corresponding to the torque down control by the movable vane 33.
As shown in FIG. 3, the start time t2 of the closing request signal output period is a time point in consideration of the closing operation response delay of the movable vane 33 from the time t3 which is the inertia phase start timing, and the end time of the closing request signal output period. t4 is a time point in which the delay in the opening operation response of the movable vane 33 is taken into consideration from the time t5, which is the end timing of the inertia phase. In this embodiment, "at the time of shifting" includes at least a shift torque down period or a shift command signal output period including immediately after the shift torque down.

Next, the vane control unit 43 will be described.
The vane control unit 43 sets the target boost pressure based on the operating state of the engine 1, and sets the target opening degree (%) of each movable vane 33 so that the actual boost pressure converges on the target boost pressure. At the same time, each movable vane 33 is adjusted to have a target opening degree. The vane control unit 43 controls the movable vane 33 under the condition of the first mode in the case other than the closing request signal output period, and controls the movable vane 33 under the condition of the second mode in the case of the closing request signal output period. There is.

The vane control unit 43 has first and second opening characteristic maps M1 and M2 (first and second control maps) that define the opening degree of the movable vane 33 by the exhaust gas energy.
As shown in FIG. 4, the first opening characteristic map M1 is a map used in the first mode. In this map, the relationship between the engine speed and the opening degree of the movable vane 33 is defined for each accelerator opening degree (for example, 100%, 50%, 25%) corresponding to a load larger than zero. These characteristics are set so that the larger the accelerator opening is, the larger the opening is, and the larger the engine speed is, the larger the opening is. As for the characteristics of each accelerator opening, the opening increases at a predetermined increase rate from the start point to the predetermined rotation speed, and the opening increases at a lower rate of increase than the predetermined increase rate at the predetermined rotation speed or higher.

As shown in FIG. 5, the second opening degree characteristic map M2 is a map used in the second mode. In this map, the relationship between the engine speed and the opening degree of the movable vane 33 is defined for each accelerator opening degree (for example, 100%, 50%, 25%) corresponding to a load larger than zero. The characteristics of each accelerator opening of the second opening characteristic map M2 are set on the closed side, that is, the closing amount is larger than the characteristics of each accelerator opening of the first opening characteristic map M1. Similar to the first opening characteristic map M1, these characteristics are set so that the larger the accelerator opening is, the larger the opening is, and the larger the engine speed is, the larger the opening is. As for the characteristics of each accelerator opening, the opening increases at a predetermined increase rate from the start point to the predetermined rotation speed, and the opening increases at a lower rate of increase than the predetermined increase rate at the predetermined rotation speed or higher.

The vane control unit 43 performs feedforward (F / F) control using the first and second opening characteristic maps M1 and M2 and a target excess in order to suppress a temporary operation delay due to the structure of the movable vane 33. Feedback (F / B) control that compares the feed pressure with the actual boost pressure can be executed.
In the F / F control, the accelerator opening corresponding to the load is obtained from the difference between the required torque calculation value represented by the closing request signal and the torque down request signal, and the accelerator opening, the engine speed, and the first and second open are obtained. The opening degree θ1 of the movable vane 33 is calculated using one of the degree characteristic maps M1 and M2. Here, the F / F control based on the first opening degree characteristic map M1 corresponds to the basic vane control, and the F / F control based on the second opening degree characteristic map M2 corresponds to the cooperative vane control.

In the F / B control, the correction opening degree θ2 of the movable vane 33 for converging the actual boost pressure to the target boost pressure by using the difference between the target boost pressure and the actual boost pressure and the F / B gain. Is calculated (see FIG. 3). The F / B gain in the second mode is set to be larger (stronger) than the F / B gain in the first mode. In the second mode, the closing amount of the movable vane 33 is increased during the high load period when the engine speed is high and the fuel is supplied, so that the operation responsiveness of the movable vane 33 is improved.

Further, the vane control unit 43 is configured to be capable of executing exhaust pressure protection control (exhaust pressure vane control) for fail-safe of the exhaust system mechanism. The exhaust pressure protection control is to reduce the exhaust pressure on the upstream side of the turbi 31 when the exhaust gas pressure (exhaust pressure) detected by the exhaust pressure sensor 54 is equal to or higher than the pressure determination threshold (Pa) which is the exhaust pressure restraint condition. The correction opening degree θ3 of the movable vane 33 of the above is calculated.
As shown in FIG. 3, when the exhaust pressure rises above the determination threshold value at times t3 to t4, the opening degree θ3 that can reduce the closing amount of the movable vane 33 according to the differential pressure between the exhaust pressure and the determination threshold value is It is calculated. Basically, during the closing request signal output period (time t2 to t4), the target opening degree θ of the movable vane 33 is set to decrease at a predetermined reduction rate. However, when the exhaust pressure rises above the determination threshold value, the target opening degree θ of the movable vane 33 is corrected to the opening side by the opening degree θ3. After the closing request signal output period ends, the target opening degree θ is rapidly increased at time t4 because the cooperative vane control is switched to the basic vane control.

Further, in the exhaust pressure protection control, in order to prevent hunting of the detected value of the exhaust pressure sensor 54, a smoothing process having low responsiveness is performed in the first mode. Specifically, in the first mode, the average value (moving average) of a plurality of exhaust pressure detection values for each detection cycle is compared with a predetermined determination threshold value, and in the second mode, the smoothing process is canceled and the detection is performed. The success or failure of the exhaust pressure restraint condition is determined by comparing the exhaust pressure detection value for each cycle with a predetermined determination threshold value. Moreover, the determination threshold value of the second mode is set to a value lower than the determination threshold value of the first mode. This is because the closing amount of the movable vane 33 is increased during the closing request signal output period, so that the movable vane 33 is easily affected by the exhaust pressure.

As described above, the vane control unit 43 switches between the first and second modes depending on the speed change state, and changes the opening degree θ1 by F / F control to the opening degree θ2 by F / B control and exhaust pressure protection control for each mode. The arbitration process is performed according to the opening degree θ3, and the final target opening degree θ of the movable vane 33 is calculated. This target opening degree θ is output to the actuator 38 as a command signal.

Next, an example of the vane control processing procedure by the ECU 40 will be described with reference to the flowchart shown in FIG. In the figure, Si (i = 1, 2, ...) Indicates each step.

First, in S1, the ECU 40 reads various signals and various control maps input from the sensors 51 to 56, and shifts to S2.
In S2, it is determined whether or not the occupant is stepping on the accelerator pedal.
As a result of the determination in S2, if the occupant is stepping on the accelerator pedal, the process proceeds to S3. As a result of the determination in S2, if the occupant has not depressed the accelerator pedal, the vehicle returns.

In S3, it is determined whether or not the automatic transmission 20 executes an upshift to the high-speed gear stage.
As a result of the determination in S3, when the upshift is executed, the upshift is executed in the accelerator depressed state, so that the close request signal is generated and output (S4).
As shown in FIG. 3, when the power-on-up shift is executed, the shift control unit 42 responds to the closing operation of the movable vane 33 from the inertia phase start timing (time t3) based on the inertia phase of the automatic transmission 20. A closing request signal is output that starts from a time point (time t2) earlier by the delay time and ends at a time point (time t4) earlier than the opening operation response delay time of the movable vane 33 from the inertia phase end timing (time t5).
As a result of the determination in S3, if the upshift to the high-speed gear stage is not executed, the gear returns.

Next, since it is the closing request signal output period, the second mode is set and the second opening characteristic map M2 is selected (S5). After the second mode is set, the F / F control (S6), which is the cooperative vane control, the F / B control (S7), and the exhaust pressure protection control (S8) are simultaneously processed in parallel.
After the completion of S6 to S8, the opening degree θ2 calculated by the F / B control process and the opening degree θ3 calculated by the exhaust pressure protection control process are arbitrated with respect to the opening degree θ1 calculated by the F / F control process. The target opening degree θ of the movable vane 33 is calculated, and a command signal corresponding to the target opening degree θ is output to the actuator 38 (S9).

After S9, in S10, it is determined whether or not the closing request signal output period has expired.
As a result of the determination in S10, when the closing request signal output period ends, the control mode is switched from the second mode to the first mode (S11) and returned. As a result of the determination in S10, if the closing request signal output period continues (has not ended), it returns to S6 to S8 and calculates the next opening degree θ1 to θ3.

Next, the operation and effect of the control device of the engine 1 will be described.
According to the control device of the engine 1, the ECU 40 has a first opening characteristic set so that when the energy of the exhaust gas is large, the opening degree of the movable vane 33 is larger than when the energy of the exhaust gas is small. Since the basic vane control for controlling the closing amount of the movable vane 33 is performed based on the map M1, when the energy of the exhaust gas is small, the flow velocity of the exhaust gas is increased by increasing the closing amount of the variable vane, and the rotation speed of the turbine 31 is increased. Exhaust gas energy can be secured by raising the temperature, and even when the exhaust gas energy is small, it can be accelerated in response to the accelerator pedal depression operation by the occupant. The time when the energy of the exhaust gas is large is when the engine speed is high or when the engine load is high (when the accelerator opening is large and the amount of depression of the accelerator pedal is large).
Further, when the energy of the exhaust gas is large, the flow velocity of the exhaust gas is slowed down by reducing the closing amount of the variable vane 33, and the exhaust pressure is lowered by lowering the rotation speed of the turbine 31 to improve fuel efficiency and output. Can be planned. The ECU 40 controls the closing amount of the movable vane 33 based on the second opening characteristic map M2 set so that the closing amount is larger than that of the first opening characteristic map M1 when the shift command signal is output. Therefore, it is possible to suppress a decrease in the actual boost pressure during shifting, and when the occupant depresses the accelerator pedal during shifting, the time required for the actual boost pressure to return to the target boost pressure is shortened. Can be transformed into.

When the shift command signal is output, the ECU 40 starts from t2, which is an earlier operation delay time of the movable vane 33 than the predicted initial phase start timing t3 of the automatic transmission 20, and is predicted to start the inertia phase end timing of the automatic transmission 20. It is characterized in that a closing request signal is generated while the movable vane 33 ends at t4, which is earlier than the operation delay time of the movable vane 33, and cooperative vane control is performed while the closing request signal is being output. As a result, the increase in exhaust gas energy due to the increase in the closing amount of the movable vane 33 can be started in consideration of the time constant delay related to the structural inertia of the movable vane 33, and the decrease in the actual boost pressure can be suppressed to accelerate the response. The sex can be further enhanced.

While the closing request signal is being output, the ECU 40 reduces the closing amount of the movable vane 33 as the engine torque (load) increases, so that the exhaust gas energy is increased while suppressing the increase in exhaust pressure due to the increase in engine torque. can do.

While the closing request signal is being output, the ECU 40 reduces the closing amount of the movable vane 33 as the engine speed increases, so that the exhaust gas energy is increased while suppressing the increase in the exhaust pressure due to the increase in the engine speed. be able to.

The ECU 40 has first and second opening characteristic maps M1 and M2, respectively, and controls the closing amount of the movable vane 33 based on the first and second opening characteristic maps M1 and M2. It is possible to simplify the configuration of the closing amount control of the movable vane 33 at the time of shifting.

Next, a modified example in which the embodiment is partially modified will be described.
1] In the above embodiment, an example of the automatic transmission 20 capable of shifting from 1st gear to 6th gear in the D range based on the shift map has been described, but at least the transmission that executes the shift torque down at the time of power-on-up shift. Anything is required, and the transmission specifications such as the number of gears can be set arbitrarily.

2] In the above embodiment, an example in which the target opening degree θ of the movable vane 33 is set to decrease at a predetermined reduction rate during the closing request signal output period (t2 to t4) has been described, but the exhaust gas energy has been described. The reduction form can be changed arbitrarily on condition of.
As shown in FIG. 7, when the reduction of the exhaust gas energy starts at time t3 in the closing request signal output period, the closing amount of the movable vane 33 is increased, for example, the target opening degree θ is set to the minimum value. You may. In particular, when the ECU 40 increases the closing amount of the movable vane 33 at the time when the engine torque starts to decrease during the closing request signal output period, the exhaust gas energy can be increased in synchronization with the decrease in the engine torque. .. Further, when the ECU 40 increases the closing amount of the movable vane 33 at the time when the engine speed starts to decrease during the closing request signal output period, the exhaust gas energy is increased in synchronization with the decrease in the engine speed. Can be done.

3] In the above embodiment, when the exhaust pressure rises above the determination threshold value, the closing amount of the movable vane 33 is set to the opening degree θ3 which decreases according to the differential pressure between the exhaust pressure and the determination threshold value. However, the opening degree of the movable vane 33 may be set to fully open (100%) at the timing when the exhaust pressure rises above the determination threshold value. As a result, the reliability of the exhaust system mechanism can be ensured.

4] In addition, a person skilled in the art can carry out the embodiment in a form in which various modifications are added to the above-described embodiment or in a combination of the respective embodiments without departing from the gist of the present invention. It also includes various modified forms.

1 Engine 20 Automatic transmission 30 Turbocharger 31 Turbine 33 Movable vane 40 ECU
M1 1st opening characteristic map M2 2nd opening characteristic map

Claims (7)

Fuel based on the shift command signal of a turbocharger with a movable vane whose opening can be adjusted to change the flow path area of the exhaust gas supplied to the turbine and an automatic transmission that can switch to multiple shift stages. In an engine control device provided with a control means capable of performing torque down control to reduce the injection amount.
The control means closes the movable vane based on a first opening characteristic set so that the opening degree of the movable vane becomes larger when the energy of the exhaust gas is large than when the energy of the exhaust gas is small. While performing basic vane control for controlling the amount, the closing amount of the movable vane is based on the second opening characteristic set so that the closing amount is larger than the first opening characteristic when the shift command signal is output. An engine control device characterized by performing coordinated vane control. The control means starts from a time when the operation delay time of the movable vane is earlier than the predicted start timing of the inertia phase of the automatic transmission when the shift command signal is output, and ends the inertia phase of the automatic transmission. The first aspect of claim 1 is to generate a closing request signal that ends at a time earlier than the timing of the operation delay time of the movable vane, and to perform the cooperative vane control while the closing request signal is being output. The engine control device described. The engine control device according to claim 2, wherein the control means reduces the closing amount of the movable vane as the engine torque increases while the closing request signal is output. The engine control device according to claim 2, wherein the control means reduces the closing amount of the movable vane as the engine speed increases while the closing request signal is output. Any one of claims 2 to 4, wherein the control means increases the closing amount of the movable vane when a decrease in engine torque is started while the closing request signal is being output. The engine control device described in. Any one of claims 2 to 4, wherein the control means increases the closing amount of the movable vane when the engine speed starts to decrease while the closing request signal is being output. The engine control device described in the section. The control means has first and second control maps in which the first and second opening characteristics are set, and controls the closing amount of the movable vane based on the first and second control maps. The engine control device according to any one of claims 1 to 6, wherein the engine control device is characterized.

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