JP4337092B2 - Supercharger control device for internal combustion engine - Google Patents

Description

  The present invention relates to a supercharger control device that is applied to an internal combustion engine having a supercharger such as a turbocharger and that suitably controls auxiliary power for the supercharger.

  In recent years, turbochargers with an electric motor that attaches an electric motor to the rotating shaft of the turbocharger and assists exhaust power according to the operating state of the internal combustion engine, and superchargers that have an electric charger attached in series to the compressor side of the turbocharger have been developed. Yes. In this case, by operating an electric motor or the like, supercharging of the turbocharger is assisted to improve the supercharging effect.

  As a control device for a turbocharger with an electric motor, for example, as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 1-1117933), an energization current to the electric motor is controlled based on an accelerator pedal depression speed and an amount of depression. What to do is known. Further, as described in Patent Document 2 (Japanese Patent Laid-Open No. 11-280510), a control method for correcting the amount of auxiliary power based on the engine speed and the load value is known.

However, when accelerating the vehicle, the engine speed changes according to the speed change operation (shift up) of the transmission, and the exhaust power decreases accordingly. In the case of an automobile (AT car) equipped with an automatic transmission, it is conceivable that the driver does not perform a shifting operation even when the vehicle is accelerated and the amount of depression of the accelerator pedal does not change. In such a case, a predetermined amount of auxiliary power is continuously added to the supercharger regardless of the change in the acceleration state due to gear shifting. Therefore, in the above-mentioned Patent Documents 1 and 2 and the like, there is a possibility that the power of the supercharger becomes excessive and insufficient, resulting in inconveniences such as deterioration of driving feeling and deterioration of fuel consumption.
Japanese Patent Laid-Open No. 1-1117933 Japanese Patent Laid-Open No. 11-280510

  The main object of the present invention is to provide a supercharger control device for an internal combustion engine that can control the power of the supercharger without excess or deficiency and thereby prevent deterioration of driving feeling and fuel consumption. is there.

  In the first aspect of the invention, the acceleration detecting means detects that the vehicle is in a predetermined acceleration state, and the shift detecting means detects that a predetermined shift operation is performed by the transmission. Further, the auxiliary power control means calculates an auxiliary power control value of the supercharger according to a shift operation of the transmission under the acceleration state when it is detected that the predetermined acceleration state is reached. The driving of the power assist device is controlled by the calculated assist power control value.

  In short, at the time of acceleration of the vehicle, one or a plurality of speed change operations are performed under a predetermined acceleration state, and the engine speed fluctuates, so that the optimum auxiliary power amount changes each time. In such a case, according to the present invention, auxiliary power control is performed following the speed change operation of the transmission, so that the power of the supercharger is controlled without excess or deficiency, thereby preventing deterioration in driving feeling and fuel consumption. be able to.

Further , in the first aspect of the invention, each time a predetermined speed change operation is performed in the transmission, the auxiliary power reset amount is calculated according to the gear ratio at that time, and the auxiliary power reset amount increases as the accelerator change amount increases. the set large, the auxiliary power control value at said calculated set auxiliary power reset amount is reset. As a result, even when the transmission operation of the transmission is repeatedly performed, the temporary excess or deficiency of the supercharger power accompanying the transmission operation is eliminated, and the auxiliary power control corresponding to the transmission operation can be performed sequentially.

In such a case, as described in claim 2 , the auxiliary power reset amount is preferably increased as the transmission gear ratio is reduced.

According to the third aspect of the present invention, after the auxiliary power control value is reset by the auxiliary power reset amount, the auxiliary power control value is attenuated as time passes. That is, the shortage of the supercharger power changes as the exhaust power increases after the acceleration starts. In this case, if the auxiliary power control value is attenuated as described above, the supercharging pressure can be controlled in accordance with the increase in exhaust power. Therefore, it becomes a more suitable composition in order to eliminate excess and deficiency of the power of a supercharger.

In such a case, as described in claim 4, it is preferable to set an attenuation rate for attenuating the auxiliary power control value in accordance with an estimation parameter capable of estimating an increase in the exhaust power. As estimation parameters, engine load, shaft torque, supercharging pressure, and turbocharger rotation speed (turbine rotation speed) can be considered, and at least one of them may be used to estimate an increase in exhaust power.

As described above, considering the increase in exhaust power, it is desirable to attenuate the auxiliary power control value. However, there is a waste time (so-called turbo lag) until the exhaust power starts to increase at the beginning of acceleration, and the waste time It is desirable to give maximum auxiliary power and give priority to the early start-up of the supercharging pressure. Therefore, in the invention according to claim 5 , when it is detected that the vehicle is in a predetermined acceleration state, the acceleration initial value of the auxiliary power control value is set based on the transmission gear ratio at that time, and the The initial acceleration value is not attenuated in a predetermined period immediately after the start of the auxiliary power control by the initial acceleration value. Thereby, appropriate auxiliary power control can be realized even in the early stage of acceleration.

The waste time until exhaust power starts to increase at the beginning of acceleration depends on the engine speed and engine load (intake pipe pressure, intake air amount, etc.). Therefore, as described in claim 6 , a non-attenuation period during which the initial acceleration value is not attenuated may be set based on at least one of the engine speed and the engine load.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. In this embodiment, an engine control system is constructed for an in-vehicle multi-cylinder gasoline engine that is an internal combustion engine, and the engine of the control system is provided with a turbocharger with an electric motor as a supercharger. First, an overall schematic configuration diagram of the engine control system will be described with reference to FIG.

  In the engine 10 shown in FIG. 1, the intake pipe 11 is provided with a throttle valve 14 whose opening is adjusted by an actuator such as a DC motor, and a throttle opening sensor 15 for detecting the throttle opening. A surge tank 16 is provided downstream of the throttle valve 14, and an intake pipe pressure sensor 17 for detecting the intake pipe pressure is provided in the surge tank 16. The surge tank 16 is connected to an intake manifold 18 that introduces air into each cylinder of the engine 10. In the intake manifold 18, an electromagnetically driven fuel injection that injects fuel near the intake port of each cylinder. A valve 19 is attached.

  An intake valve 21 and an exhaust valve 22 are respectively provided in the intake port and the exhaust port of the engine 10, and an air / fuel mixture is introduced into the combustion chamber 23 by the opening operation of the intake valve 21, and the exhaust valve 22. By the opening operation, the exhaust gas after combustion is discharged to the exhaust pipe 24. A spark plug 25 is attached to the cylinder head of the engine 10 for each cylinder, and a high voltage is applied to the spark plug 25 at a desired ignition timing through an ignition device (not shown) including an ignition coil. By applying this high voltage, a spark discharge is generated between the opposing electrodes of each spark plug 25, and the air-fuel mixture introduced into the combustion chamber 23 is ignited and used for combustion.

  A crank angle sensor 26 that outputs a rectangular crank angle signal is attached to the cylinder block of the engine 10 at every predetermined crank angle (for example, at a cycle of 30 ° CA) as the engine 10 rotates.

A turbocharger 30 is disposed between the intake pipe 11 and the exhaust pipe 24. The turbocharger 30 has a compressor impeller 31 provided in the intake pipe 11 and a turbine wheel 32 provided in the exhaust pipe 24, which are connected by a rotary shaft 33. The rotating shaft 33 is provided with a motor 34 as a power assist device. The motor 34 is provided with a temperature sensor 35 for detecting the motor temperature.

  In the turbocharger 30, the turbine wheel 32 is rotated by the exhaust gas flowing through the exhaust pipe 24, and the rotational force is transmitted to the compressor impeller 31 via the rotation shaft 33. The compressor impeller 31 compresses and supercharges intake air flowing through the intake pipe 11. The motor 34 is operated by power supply from a vehicle battery (not shown), and auxiliary power is added to the turbocharger 30 by the operation of the motor 34. The air supercharged by the turbocharger 30 is cooled by the intercooler 37 and then fed downstream. As the intake air is cooled by the intercooler 37, the charging efficiency of the intake air is increased.

  FIG. 3 shows the transition of the supercharging pressure during vehicle acceleration. When the throttle opening increases as shown in the drawing at the timing t1 at the start of acceleration, the exhaust power rises with a delay from t1. Therefore, when the auxiliary power by the motor 34 is not added, the supercharging pressure rises with a delay due to insufficient exhaust power (shown as “no assist” in the figure). In contrast, the auxiliary power by the motor 34 is added to compensate for the exhaust power shortage, and the boost pressure rises early (shown as “with assist” in the figure).

  As is well known, the engine ECU 50 is mainly composed of a microcomputer composed of a CPU, ROM, RAM, and the like, and executes various control programs stored in the ROM, so that the engine 10 can be operated in accordance with the engine operating state each time. Implement various controls. That is, the engine ECU 50 receives detection signals from the throttle opening sensor 15, the intake pipe pressure sensor 17, and the crank angle sensor 26 described above, and detects the amount of depression of the accelerator pedal (accelerator opening AP). Detection signals are input from an accelerator opening sensor 27 for detecting the shift position and a shift switch 28 for detecting a shift position (shift position Ps) of a multi-stage automatic transmission (not shown). The engine ECU 50 calculates the fuel injection amount, the ignition timing, and the like based on various detection signals that are input as needed, and controls the drive of the fuel injection valve 19 and the spark plug 2.

  Further, the engine ECU 50 controls the motor 34 of the turbocharger 30 to add auxiliary power to the turbocharger 30 during vehicle acceleration so that a desired supercharging pressure can be obtained quickly. Details thereof will be described later. In the present embodiment, the auxiliary power control of the turbocharger 30 is also referred to as assist control.

  The motor ECU 60 controls the power supplied to the motor 34 of the turbocharger 30 based on the signal from the engine ECU 50 and the motor efficiency.

  FIG. 2 is a functional block diagram of the engine ECU 50 according to the supercharging pressure control of the turbocharger 30.

  In the engine ECU 50, the accelerator change amount calculation means M1 calculates a change amount per unit time (hereinafter referred to as an accelerator change amount ΔAP) based on the accelerator opening AP calculated from the detection signal of the accelerator opening sensor 27. . The assist permission determination means M2 detects that the vehicle has entered a predetermined acceleration state based on the accelerator change amount ΔAP and the intake pipe pressure PM, and when detecting that the vehicle has entered the predetermined acceleration state, assist control described later. The execution of the assist control by the means M6 is permitted or prohibited.

  The reset calculation means M3 calculates the reset amount Wa of the auxiliary power at the start of acceleration and at the time of shift switching based on the accelerator change amount ΔAP and the shift position Ps. Here, the reset amount Wa is for setting the optimum auxiliary power even when the automatic transmission is shift-changed as appropriate when the vehicle is accelerated, and is calculated according to the degree of acceleration in each case.

  The hold time calculation means M4 calculates a hold time Th for maintaining the auxiliary power W after reset based on the engine speed Ne. The hold time Th is a time for maintaining the maximum auxiliary power at the start of acceleration, and corresponds to a period in which the power is insufficient due to the turbo lag (supercharging pressure rising waste time).

  The attenuation amount calculating means M5 calculates an attenuation amount Wr for attenuating the auxiliary power W based on the intake pipe pressure change amount ΔPM. In other words, the auxiliary power W is intended to compensate for the shortage of exhaust power. However, the auxiliary power W is attenuated as the exhaust power increases so that the auxiliary power W is not wasted and the efficiency is improved. Yes. In the present embodiment, the exhaust power deficiency is determined according to the amount of change in the intake pipe pressure PM, and the attenuation Wr is set in accordance with the exhaust power deficiency each time.

  When the assist control is permitted by the assist permission determination unit M2, the assist control unit M6 assists as an auxiliary power control value based on the shift position Ps, the reset amount Wa, the hold time Th, and the attenuation amount Wr each time. The power W is determined, and assist control is performed using the auxiliary power W.

  The motor ECU 60 receives the auxiliary power W from the engine ECU 50, and controls the power supplied to the motor 34 based on the auxiliary power W while considering the motor efficiency and the like. At this time, by monitoring the motor temperature, the supplied power can be corrected based on the motor temperature characteristics.

  In the present embodiment, the assist permission means M2 corresponds to “acceleration detection means” and “shift detection means”, and the reset amount calculation means M3 and assist control means M6 correspond to “auxiliary power control means”. The attenuation amount calculation means M5 corresponds to “attenuation rate setting means”.

  The assist control of the present embodiment will be described. FIG. 4 shows a base routine of the engine ECU 50, which is executed every 4 ms, for example. When starting the system, the engine ECU 50 first executes an initial routine in step S101, and then executes an assist routine in, for example, every 16 ms in step S102.

  5 and 6 are flowcharts showing the assist routine, and the means M1 to M6 of FIG. 2 are realized by this routine.

  First, in step S201, the intake pipe pressure PM is read, and in the subsequent step S202, the accelerator opening AP is read. In step S203, an accelerator change amount ΔAP is calculated (ΔAP = APi−APi−1). Thereafter, in step S204, it is determined whether or not the accelerator change amount ΔAP is equal to or greater than a predetermined determination value APth. If ΔAP <APth, it is determined that the acceleration is not an acceleration that requires assist control, and the assist permission flag XTA and XTAB is set to 0 (steps S205 and S206). If ΔAP ≧ APth, it is determined that the acceleration is necessary for assist control, and 1 is set to the assist permission flag XTA (step S207).

  Thereafter, in steps S208 to S212, a calculation process of the hold time Th at the start of acceleration is performed. That is, in step S208, it is determined whether or not the assist permission flags XTA and XTAB are inconsistent. Since XTA = 1 and XTAB = 0 at the start of acceleration, XTA ≠ XTAB, and the acceleration start determination flag F1 is set to 1 in step S209, and the counter CNT is initialized to 0 after the acceleration is started in step S210. In step S211, a hold time Th for maintaining the maximum auxiliary power in the early stage of acceleration is calculated. Specifically, the hold time Th is calculated based on the engine speed Ne each time using the map shown in FIG. In this case, as described above, the hold time Th is a period in which the power is insufficient due to the turbo lag (the boost pressure rise waste time), and the turbo lag changes according to the rate of increase of the exhaust power, which corresponds to the engine speed Ne. ing. That is, when the engine speed Ne is low, the exhaust power increases slowly and the turbo lag becomes large. Conversely, when the engine speed Ne is high, the turbo lag becomes small. From this, the relationship of FIG. 8 is defined.

  Except when acceleration is started (during acceleration or after completion of acceleration), XTA = XTAB, and the acceleration start determination flag F1 is set to 0 in step S212.

  Thereafter, in step S213, the shift position Ps is detected. In step S214, the auxiliary power reset amount Wa is calculated. Specifically, the map shown in FIG. 9 is used, and the reset amount Wa is calculated based on the shift position Ps and the accelerator change amount ΔAP each time. In this case, the larger the accelerator change amount ΔAP is, or the higher the shift position Ps is (the smaller the gear ratio is), the larger the reset amount Wa is obtained.

  Thereafter, in steps S215 to S220, the attenuation amount Wr is calculated. That is, in step S215, it is determined whether or not the value of the counter CNT after the start of acceleration at that time is less than the hold time Th. If CNT <Th, the attenuation Wr is set to 0 in step S216, and the counter CNT is incremented by 1 in step S217 after starting acceleration. If CNT ≧ Th, the intake pipe pressure change amount ΔPM is calculated in step S218 (ΔPM = PMi−PMi−1). In step S219, the attenuation amount Wr is calculated based on the intake pipe pressure change amount ΔPM. To do. Specifically, the attenuation amount Wr is calculated based on the change amount ΔPM of the intake pipe pressure each time using the map shown in FIG. In this case, if the exhaust power increases, the amount of change ΔPM in the intake pipe pressure increases. Therefore, if ΔPM is large, there is no problem even if the auxiliary power W is attenuated. Therefore, the amount of attenuation Wr is increased as ΔPM is increased. In step S220, the counter CNT after starting acceleration is guarded at the upper limit with the hold time Th.

  Thereafter, in step S221 in FIG. 6, a change in the shift position Ps is determined. Here, a change in the shift position Ps is determined by comparing the current shift position Psi with the previous shift position Psi-1. If the shift position Ps has changed, Psi ≠ Psi−1, and the routine proceeds to step S222, where 1 is set to the shift change point determination flag F2. On the other hand, if the shift position Ps has not changed, Psi = Psi-1 is established, and the routine proceeds to step S223, where 0 is set to the shift change point determination flag F2.

  In step S224, it is determined whether one of the acceleration start determination flag F1 and the shift change point determination flag F2 is 1. In the case of YES, the reset amount Wa is set as the auxiliary power W in step S225. In other words, a reset request is generated at the time of starting acceleration and shifting of the automatic transmission, and the auxiliary power W is reset. If step S224 is NO, the auxiliary power W is subtracted by the attenuation amount Wr in step S226.

  Thereafter, in step S227, it is determined whether or not the counter CNT after starting acceleration is larger than the hold time Th. If CNT ≧ Th, whether or not the intake pipe pressure PM is in a stable state in step S228. Is determined. If CNT <Th, and if CNT ≧ Th and the intake pipe pressure PM is not stable, the process proceeds to step S229 where XTAB is replaced with XTA. If CNT ≧ Th and the intake pipe pressure PM is stable, the process proceeds to step S230 where the auxiliary power W is set to zero. Finally, in step S231, the auxiliary power W is output to the motor ECU 60.

  That is, in steps S227 to S230, basically, the necessity of the auxiliary power W is determined according to the state of the intake pipe pressure PM, and the assist control is continued until the intake pipe pressure PM becomes stable. The assist control is ended based on the determination that the tube pressure PM is stabilized (W = 0). However, the period of CNT <Th is a waste time due to the turbo lag, and the rise of the intake pipe pressure PM is delayed, so that the assist control is performed without monitoring the state of the intake pipe pressure PM (in step S230). W = 0)

  Next, calculation processing of the motor ECU 60 will be described. FIG. 7 is a flowchart showing a supply power calculation routine executed by the motor ECU 60.

  In step S301, the requested auxiliary power W is read based on the received signal from the engine ECU 50. This auxiliary power W is detected in units of “kW”, and in step S302, the electric power We “kW” supplied to the motor 34 is calculated from the auxiliary power W and the motor efficiency ηm (We = W / ηm).

  Next, the assist control will be described more specifically with reference to the time chart of FIG. FIG. 11 shows the behavior when the vehicle accelerates when the driver depresses the accelerator pedal.

  In FIG. 11, at time t11, as the accelerator opening AP increases, the accelerator change amount ΔAP becomes equal to or greater than the determination value APth, so that the assist permission flag XTA is set to 1. Since XTA ≠ XTAB at this time, it is determined that the acceleration is started, and 1 is set to the acceleration start determination flag F1. Thereby, the assist control is started after t11. Note that the engine speed Ne increases as the accelerator opening AP increases.

  With the start of the assist control, the reset amount Wa is calculated according to the accelerator change amount ΔAP and the shift position Ps at that time, and the reset amount Wa is set to the auxiliary power W. Here, looking at the change in the auxiliary power W in the early stage of acceleration in more detail with reference to FIG. 12, at the timing t11, the hold time Th is set and the counter CNT starts counting up after the acceleration starts. Since the attenuation amount Wr is 0 during the period up to the timing t12 when the CNT value reaches the hold time Th, the auxiliary power W is held at the initial set value (the reset amount Wa at t11). Then, after the timing t12 when the CNT value reaches the hold time Th, the auxiliary power W is attenuated according to the attenuation amount Wr set each time.

  Returning to the description of FIG. 11, at timing t <b> 13, upshifting is performed in the automatic transmission as the engine speed Ne increases (the vehicle speed state is also appropriately reflected), and the shift position Ps changes. Due to this shift-up, the engine speed Ne rapidly decreases, so new auxiliary power W is required. In such a case, 1 is set to the shift change point determination flag F2 at the same time as the shift position Ps changes. Then, the reset amount Wa is calculated again according to the accelerator change amount ΔAP and the shift position Ps at that time, and the reset amount Wa is set to the auxiliary power W. Further, after t13, the auxiliary power W is attenuated based on the change in the intake pipe pressure PM. Thereafter, the same processing is performed every time the speed change operation is performed (timing t14, t15). When the intake pipe pressure PM is stabilized, it is determined that no further assist control is necessary, and after time t17, the auxiliary power W = 0 is set. At timing t16, since ΔAP <APth, the assist permission flags XTA and XTAB are cleared to zero.

  In FIG. 11, the difference between the conventional control and the control of the present embodiment will be described. In the conventional control, as indicated by a one-dot chain line as a transition of the auxiliary power W, a substantially constant auxiliary power W is continuously applied during acceleration regardless of whether or not there is a shift. As a result, excess or deficiency of the power of the turbocharger 30 occurs. For example, when the power is excessive, the supercharging pressure overshoots as indicated by a one-dot chain line as a transition of the supercharging pressure. This can be said to use wasteful power, and there is also a possibility that the driving feeling is further deteriorated. On the other hand, when the power is insufficient, the acceleration is slow. On the other hand, in the present embodiment, optimal assist control that follows the shift operation of the automatic transmission is performed, so that excess or deficiency of the power of the turbocharger 30 is eliminated, and inconveniences in the conventional control can be suppressed.

  According to the embodiment described above in detail, the following excellent effects can be obtained.

  When the vehicle is accelerated, the auxiliary power W of the turbocharger 30 is calculated in accordance with the speed change operation of the automatic transmission, and the driving of the motor 34 is controlled by the calculated auxiliary power W, which is optimal each time. Assist control can be performed with the auxiliary power W. As a result, the excess or deficiency of power can be solved, and acceleration slack and overshoot of power can be suppressed. In addition, useless power consumption can be suppressed. Accordingly, it is possible to prevent deterioration of driving feeling and fuel consumption.

  In addition, each time a speed change operation is performed in the automatic transmission, the auxiliary power W is reset according to the shift position (speed ratio) at that time, and after the reset, the auxiliary power W is attenuated, so that the speed change operation is performed during the acceleration period. Even if the operation is repeated, the temporary power shortage associated with the shifting operation is resolved. Even if the exhaust power increases after resetting, the auxiliary power W can be controlled following the exhaust power. Therefore, it becomes a more suitable composition in order to eliminate excess and deficiency of the power of a supercharger.

  At the start of acceleration, since the auxiliary power W is not attenuated until the hold time Th elapses, the maximum auxiliary power is generated within the waste time (so-called turbo lag) until the exhaust power in the initial stage of acceleration starts to increase, and the boost pressure is increased at an early stage. Start-up can be prioritized.

  In addition, this invention is not limited to the content of description of the said embodiment, For example, you may implement as follows.

  In the above embodiment, the presence or absence of the shift operation of the automatic transmission is detected by the shift position detection signal (shift position Ps), but this is changed. For example, it is possible to determine from the engine speed Ne and the vehicle speed SPD, and the details are shown in FIG. The process of FIG. 13 is a flowchart showing a part of the assist routine of FIGS. 5 and 6 described above, and is executed in place of steps S213 to S221 of FIGS. Note that the processing for calculating the attenuation amount Wr (S215 to S220 in FIG. 5) is applied without change.

  In FIG. 13, the vehicle speed SPD is detected in step S401, and the gear ratio Rg is calculated in the subsequent step S402. At this time, the gear ratio Rg is calculated based on the vehicle speed SPD, the engine rotational speed Ne, the vehicle-specific differential gear ratio (difference ratio), and the tire radius. Thereafter, in step S403, the auxiliary power reset amount Wa is calculated. Specifically, the map shown in FIG. 14 is used, and the reset amount Wa is calculated based on the gear ratio Rg and the accelerator change amount ΔAP each time. In this case, the larger the accelerator change amount ΔAP or the smaller the gear ratio Rg (the smaller the gear ratio), the larger the value that is required for the reset amount Wa. Thereafter, in steps S404 to S409, the same attenuation amount Wr calculation process as in steps S215 to S220 of FIG. 5 is performed. In step S410, a change in the gear ratio Rg is determined. That is, the current gear ratio Rgi is compared with the previous gear ratio Rgi-1, and if Rgi ≠ Rgi-1, it is determined that a predetermined shift operation has been performed. However, the gear ratio Rg may have a range, and Rgi and Rgi-1 may be compared and determined depending on whether the corresponding ranges match. According to the method of FIG. 13, it is possible to detect not only an AT vehicle but also a shift operation of a vehicle equipped with a so-called AMT (automatic manual transmission).

  In the above embodiment, when the auxiliary power is reset for each shift operation under a predetermined acceleration state of the vehicle, the reset amount Wa is set every time with an absolute amount based on 0. Instead, the previous reset is performed. An increase / decrease amount with respect to the amount Wa may be calculated, and the auxiliary power may be reset based on the increase / decrease value. Specifically, as shown in FIG. 15, the reset amount Wa1 is calculated at the start of acceleration, and thereafter, the auxiliary power addition values ΔW1, ΔW2, and ΔW3 are added each time a shift operation is performed, and the addition value is reset last time. The auxiliary power is reset in addition to the auxiliary power at the time.

  In the above embodiment, the auxiliary power reset amount Wa and the attenuation amount Wr are set each time the transmission is shifted after the vehicle starts acceleration. The configuration is changed as follows. . For example, in FIG. 16, (a) shows assist control in which attenuation is not performed after resetting of auxiliary power, and (b) is attenuated after resetting of auxiliary power, but the reset amount Wa is the same value every time. The assist control is set to (fixed value). 16A and 16B, TA is an acceleration period of the vehicle, t21, t22, and t23 in (a), and t31, t32, and t33 in (b) are shift operation timings, respectively. That is, in the case of (a), the auxiliary power attenuation process in the assist control is omitted, and in the case of (b), the reset amount variable setting process in the assist control is omitted. Even so, it is possible to eliminate excess and deficiency of power and to prevent deterioration of driving feeling and fuel consumption.

  In the above embodiment, the hold time Th is set after the start of acceleration of the vehicle, and the auxiliary power W is not attenuated until the hold time Th elapses. The auxiliary power W may not be attenuated during the period until the speed change operation (shift up) is performed.

  When calculating the reset amount Wa (auxiliary power reset amount), the supercharging pressure of the turbocharger 30 or the turbine rotational speed may be used. In this case, the reset amount Wa may be increased as the supercharging pressure is lower or the turbine rotational speed is lower.

  The attenuation amount Wr of the auxiliary power W may be set in accordance with an estimation parameter that can estimate the increase in exhaust power. The estimation parameter is other than the above-described intake pipe pressure change ΔPM (see FIG. 10). In addition, the shaft torque, the supercharging pressure, and the rotational speed of the supercharger (turbine rotational speed) may be considered, and the increase in exhaust power may be estimated using at least one of these.

  In the above embodiment, the hold time Th for holding the acceleration initial value of the auxiliary power W is calculated based on the engine speed Ne (see FIG. 8), but instead, based on the intake pipe pressure PM. Alternatively, the hold time Th may be calculated based on the engine speed Ne and the intake pipe pressure PM.

  Acceleration detection means that detects the acceleration state based on the amount of change in throttle opening instead of the amount based on the amount of change in accelerator opening, or the acceleration state based on the amount of change in accelerator opening and throttle opening May be detected.

  As the shift detection means, instead of or in addition to the shift position signal, the shift operation of the transmission is detected using at least one of the engine speed and its differential value, the differential value of the accelerator opening, and the vehicle speed. May be. In addition to detecting the shift change of the automatic transmission (multi-stage transmission), the shift detection means includes that the speed ratio of the continuously variable transmission has been changed by a predetermined amount in a vehicle equipped with a continuously variable transmission. It includes what is detected.

  As a supercharger, in addition to the turbocharger having the structure in which the motor is attached to the rotating shaft as described above, an electric charger as a power auxiliary device may be attached in series on the compressor side.

It is a block diagram which shows the outline of the engine control system in embodiment of invention. It is a functional block diagram of engine ECU concerning supercharging pressure control. It is a time chart which shows the relationship between the exhaust power at the time of acceleration, and a supercharging pressure. It is a flowchart which shows the base routine of engine ECU. It is a flowchart which shows an assist routine. FIG. 6 is a flowchart illustrating an assist routine following FIG. 5. It is a flowchart which shows the base routine of motor ECU. It is a figure which shows a hold time calculation map. It is a figure which shows a reset amount calculation map. It is a figure which shows an attenuation amount calculation map. It is a time chart for demonstrating assist control. It is a time chart for demonstrating the auxiliary power hold process at the time of an acceleration start. It is a flowchart which shows a part of assist routine in another form. It is a figure which shows a reset amount calculation map. It is a time chart which shows the example of control of auxiliary power in another form. It is a time chart which shows the example of control of auxiliary power in another form.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Engine, 30 ... Turbocharger, 34 ... Motor, 50 ... Engine ECU, M2 ... Assist permission means, M3 ... Reset amount calculation means, M5 ... Attenuation amount calculation means, M6 ... Assist control means.

Claims (6)

An internal combustion engine having a supercharger for increasing intake efficiency using exhaust power and a power assist device, and a transmission for transmitting the rotation output of the internal combustion engine to a wheel side at a variable setting gear ratio A supercharger control device for an internal combustion engine, which is applied to a vehicle and configured to add auxiliary power to the supercharger by driving the power auxiliary device;
Acceleration detecting means for detecting that the vehicle has entered a predetermined acceleration state;
Shift detection means for detecting that a predetermined shift operation has been performed by the transmission;
When it is detected that the predetermined acceleration state is reached, the auxiliary power control value of the supercharger is calculated according to the shift operation of the transmission under the acceleration state, and the calculated auxiliary power control value Auxiliary power control means for controlling the driving of the power auxiliary device by
Equipped with a,
The auxiliary power control means calculates an auxiliary power reset amount according to the gear ratio at each time when a predetermined shift operation is performed in the transmission, and increases the auxiliary power reset amount as the accelerator change amount increases. A supercharger control device for an internal combustion engine, wherein the superpower control value is set and the auxiliary power control value is reset with the calculated auxiliary power reset amount . The supercharger control device for an internal combustion engine according to claim 1, wherein the auxiliary power control means increases the auxiliary power reset amount as the gear ratio of the transmission decreases . The supercharger control device for an internal combustion engine according to claim 1 or 2, wherein the auxiliary power control means attenuates the auxiliary power control value as time passes after the auxiliary power control value is reset by the auxiliary power reset amount . The supercharger control device for an internal combustion engine according to claim 3 , further comprising an attenuation rate setting means for setting an attenuation rate for attenuating the auxiliary power control value in accordance with an estimation parameter capable of estimating an increase in the exhaust power. . When detecting that the vehicle has entered the predetermined acceleration state, the auxiliary power control means sets an initial acceleration value of the auxiliary power control value based on the gear ratio of the transmission at that time, and The supercharger control device for an internal combustion engine according to claim 3 or 4, wherein the acceleration initial value is not attenuated in a predetermined period immediately after the start of the auxiliary power control by the initial value . The supercharger control device for an internal combustion engine according to claim 5, wherein a non-attenuation period in which the initial acceleration value is not attenuated is set based on at least one of an engine speed and an engine load .