JP2006189008A - Control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a feeling of strangeness given to a driver and accelerate a vehicle.
An ECU calculates a fully closed engine torque T (3), which is an engine torque when an accelerator opening is 0, from a map stored in a memory, based on a throttle opening during idling. Based on step (S110), step (S114) for calculating the minimum torque T (2) actually generated by the engine during idling, and a map stored in the memory based on the throttle opening calculated from the accelerator opening By calculating the required torque T (1) to the engine (S122) and adding the torque obtained by subtracting the fully closed engine torque T (3) from the minimum torque T (2) to the required torque T (1). The program is executed including the step of correcting the required torque T (1) and calculating the corrected required torque T (4) (S124).
[Selection] Figure 3

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a technique for calculating a required torque for the internal combustion engine and controlling the internal combustion engine based on the calculated required torque.

  Conventionally, the driving force of a vehicle is controlled by a driver operating an accelerator pedal. Japanese Patent Application Laid-Open No. 10-103122 (Patent Document 1) discloses a vehicle driving force control device that sets a target driving force from an accelerator opening and sets a throttle opening based on the set target driving force. The vehicle driving force control device described in Patent Document 1 includes a vehicle speed detection unit, an accelerator opening detection unit, a shift map using the vehicle speed and the accelerator opening as parameters, a vehicle speed detection unit, and an accelerator opening detection unit. A shift control unit for controlling the automatic transmission by determining a gear position from a detected shift speed map based on the detected actual vehicle speed and accelerator opening, and a target driving force map using the vehicle speed and accelerator opening as parameters; A target driving force setting unit that sets a target driving force based on the target driving force map from the actual vehicle speed and the accelerator opening detected by the vehicle speed detecting unit and the accelerator opening detecting unit, and a target throttle opening based on the target driving force. A target throttle opening setting unit that sets the degree of throttle, a throttle valve driving unit that drives the electric throttle valve of the engine intake system so as to achieve the target throttle opening, and a shift map Using the rewritable correction value fixed point data storage unit that stores the correction value for the target throttle opening in correspondence with each of the fixed points set in advance on the speed line, the shift map and the correction value fixed point data storage unit, A correction value interpolation calculation unit for obtaining a correction value corresponding to the actual vehicle speed and the accelerator opening detected by the vehicle speed detection unit and the accelerator opening detection unit by interpolation calculation, and a target set by the target throttle opening setting unit A target throttle opening correction unit that corrects the throttle opening with a correction value obtained by interpolation calculation, a shift shock measurement unit that measures the magnitude of a shift shock at the time of shifting near each fixed point, and an excessive amount based on the measurement result The correction value corresponding to the fixed point in the correction value fixed point data storage unit is updated in a direction to reduce the shift shock at the fixed point at which the variable shift shock is measured. To and a fixed-point data updating unit.

According to the vehicle driving force control device described in this publication, by determining a correction value for the target throttle opening directly in relation to the shift map, it is possible to eliminate the driving force step before and after the shift or to provide an appropriate step. In addition to this, the target throttle opening can be corrected in consideration of fuel consumption and drivability on the shift map.
JP-A-10-103122

  By the way, when the internal combustion engine with an accelerator opening of 0 is idle, idle speed control (ISC: Idle) is performed in which the internal combustion engine is controlled in consideration of the state of the internal combustion engine itself, the state of auxiliary equipment, the environment outside the vehicle, and the like. Some of them execute Speed Control. In the idling speed control, since the accelerator opening is zero, the throttle opening is changed so that a desired torque can be obtained regardless of the accelerator opening. Therefore, in the driving force control apparatus for a vehicle described in Japanese Patent Application Laid-Open No. 10-103122, when the throttle opening is determined by setting the accelerator opening to 0, and when the accelerator opening is 0 (during idling) ) May cause a deviation from the actually output torque. Therefore, if the torque actually output at the time of idling is higher than the torque obtained by the throttle opening set with the accelerator opening set to 0, if the accelerator opening is increased by the driver's accelerator operation, The vehicle will not be accelerated until they match. If the torque actually output during idling is lower than the torque obtained from the throttle opening set with the accelerator opening set to 0, the internal combustion engine is increased when the accelerator opening is increased by the driver's accelerator operation. Output torque changes stepwise. In any case, there is a problem that the driver may feel uncomfortable.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a control device for an internal combustion engine that can suppress a sense of discomfort given to the driver and accelerate the vehicle. It is.

  An internal combustion engine control apparatus according to a first aspect of the present invention is a first setting means for setting a throttle opening based on an accelerator opening, and a throttle opening when the internal combustion engine is in an idle state. The first required torque for the internal combustion engine is calculated based on the second setting means and the throttle opening set by the first setting means, and the throttle opening set by the second setting means is set. Based on a deviation between the second required torque and the output torque based on the means for calculating the second required torque to the internal combustion engine, the means for calculating the output torque of the internal combustion engine in the idle state. Correction means for correcting the required torque of 1 and control means for controlling the internal combustion engine based on the corrected first required torque.

  According to the first aspect of the invention, the first required torque for the internal combustion engine corresponding to the driver's request is calculated based on the throttle opening degree set by the accelerator opening degree (by the first setting means). However, when the accelerator opening is 0, that is, when the internal combustion engine is in an idle state, the throttle opening is set by the second setting means regardless of the idle opening. Therefore, there is a difference between the first required torque calculated when the internal combustion engine is in an idle state (accelerator opening is 0) and the output torque actually generated by the internal combustion engine. In order to eliminate this deviation, when the internal combustion engine is in an idle state, the second required torque is calculated based on the throttle opening set (by the second setting means), and the second required torque and the idle state are calculated. The first required torque is corrected based on the deviation of the output torque of the internal combustion engine at. For example, the first required torque is corrected by adding a torque obtained by subtracting the first required torque from the output torque to the first required torque. Thereby, it is possible to suppress a deviation between the first required torque calculated when the internal combustion engine is in the idle state (the accelerator opening is 0) and the output torque actually generated by the internal combustion engine. Therefore, when the accelerator opening is increased, it is possible to suppress the torque from changing or the torque from changing suddenly stepwise. As a result, it is possible to provide a control device for an internal combustion engine that can suppress the uncomfortable feeling given to the driver and accelerate the vehicle.

  In the control apparatus for an internal combustion engine according to the second invention, in addition to the configuration of the first invention, the correcting means adds a torque obtained by subtracting the second required torque from the output torque to the first required torque. Including means.

  According to the second invention, it is possible to suppress a deviation between the first required torque calculated when the internal combustion engine is in an idle state (the accelerator opening is 0) and the output torque actually generated by the internal combustion engine. . As a result, when the accelerator opening is increased, it is possible to prevent the torque from changing or the torque from changing suddenly stepwise.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  Hereinafter, a power train of a vehicle including a control device according to an embodiment of the present invention will be described. The control device according to the present embodiment is realized by an ECU (Electronic Control Unit) 1000 shown in FIG. In the present embodiment, the automatic transmission will be described as an automatic transmission having a planetary gear type transmission mechanism provided with a torque converter as a fluid coupling. The present invention is not limited to an automatic transmission having a planetary gear type transmission mechanism, and may be a continuously variable transmission such as a belt type continuously variable transmission.

  With reference to FIG. 1, a power train of a vehicle including a control device according to the present embodiment will be described. As shown in FIG. 1, the power train of this vehicle includes an engine 100, a torque converter 200, an automatic transmission 300, and an ECU 1000.

  An output shaft (crankshaft) of engine 100 is connected to an input shaft of torque converter 200. Engine 100 and torque converter 200 are connected by a rotating shaft. Therefore, output shaft speed NE (engine speed NE) of engine 100 detected by engine speed sensor 400 and input shaft speed (pump speed) of torque converter 200 are the same.

  The torque converter 200 includes a lock-up clutch 210 that directly connects the input shaft and the output shaft, a pump impeller 220 on the input shaft side, a turbine impeller 230 on the output shaft side, and a one-way clutch 250. It is comprised from the stator 240 which expresses an amplification function. Torque converter 200 and automatic transmission 300 are connected by a rotating shaft. An output shaft rotational speed NT (turbine rotational speed NT) of torque converter 200 is detected by turbine rotational speed sensor 410. The output shaft rotational speed NOUT of the automatic transmission 300 is detected by the output shaft rotational speed sensor 420.

  The ECU 1000 that controls these power trains includes an engine ECU 1010 that controls the engine 100 and an ECT (Electronic Controlled Automatic Transmission) _ECU 1020 that controls the automatic transmission 300.

  The ECT_ECU 1020 receives a signal representing the turbine rotational speed NT from the turbine rotational speed sensor 410 and a signal representing the output rotational speed NOUT from the output shaft rotational speed sensor 420 from the accelerator opening sensor 2000 to an accelerator pedal (not shown). A signal representing the opening (position) is input. The ECT_ECU 1020 receives a signal representing the engine speed NE detected by the engine speed sensor 400 and a signal representing the throttle opening detected by the throttle position sensor 2010 from the engine ECU 1010.

  These rotation speed sensors are provided to face the teeth of the rotation detection gear attached to the input shaft of torque converter 200, the output shaft of torque converter 200, and the output shaft of automatic transmission 300. These rotational speed sensors are sensors that can detect slight rotations of the input shaft of the torque converter 200, the output shaft of the torque converter 200, and the output shaft of the automatic transmission 300. This is a sensor using a magnetoresistive element.

  With reference to FIG. 2, engine ECU 1010 and ECT_ECU 1020 will be further described. The engine ECU 1010 is in an idle state of the engine 100 (when the accelerator opening is 0), the state of the engine 100 itself (cooling water temperature, lubricating oil temperature, etc.), auxiliary equipment (alternator, air conditioner, and oil pump). Etc.) and the idling speed control based on the environment outside the vehicle. In idle speed control, the output torque of the engine 100 is controlled by setting the throttle opening.

  The ECT_ECU 1020 calculates the throttle opening based on the accelerator opening. The throttle opening is calculated based on a map stored in the memory of ECU 1000. Further, ECT_ECU 1020 calculates required torque T (1) for engine 100 based on the calculated throttle opening and turbine rotational speed NT. Requested torque T (1) is calculated based on a map stored in the memory of ECU 1000.

  When the accelerator opening is 0, that is, when the engine 100 is idling, the required torque T (1) is calculated using the throttle opening detected by the throttle position sensor 2010.

  At the time of shifting the automatic transmission 300, the required torque T (1) is calculated based on the output shaft rotation speed NOUT and the turbine rotation speed NT calculated from the gear stage after the shift. Thereby, the required torque T (1) after the shift can be calculated.

  Further, the ECT_ECU 1020 uses the same map as that used when calculating the required torque T (1), based on the throttle opening during idle (hereinafter referred to as the idle slot opening) and the turbine speed NT. Then, an engine torque (fully closed engine torque) T (3) when the accelerator opening is 0 is calculated. Therefore, the required torque T (1) calculated when the accelerator opening is 0 is the same as the fully closed engine torque T (3).

  Further, ECT_ECU 1020 calculates engine speed NE (fully closed engine speed) when the accelerator opening is 0 based on the idle slot opening and turbine speed NT. The fully closed engine rotation is calculated using a map stored in advance in the memory of ECU 1000. The calculated fully closed engine rotation is transmitted to engine ECU 1010.

  Engine ECU 1010 calculates the output (idle power) of engine 100 during idling from the idle slot opening and the current engine speed NE. The idle power is calculated using a map stored in the memory of the ECU 1000.

  Further, engine ECU 1010 calculates torque (minimum torque) T (2) generated in engine 100 during idling based on the calculated idle power and the fully closed engine rotation transmitted from ECT_ECU 1020. The calculated minimum torque T (2) is transmitted to the ECT_ECU 1020.

  The ECT_ECU 1020 corrects the required torque T (1) by adding a torque obtained by subtracting the fully closed engine torque T (3) from the minimum torque T (2) to the required torque T (1), thereby correcting the corrected required torque. T (4) is calculated. The calculated correction request torque T (4) is transmitted to the engine ECU 1010.

  When engine 100 is not in an idle state, engine ECU 1010 controls engine 100 based on correction request torque T (4). Specifically, a throttle opening is set so as to realize the correction required torque T (4), and a throttle valve (not shown) is controlled.

  With reference to FIG. 3, a control structure of a program executed by ECU 1000 of the control device according to the present embodiment when engine 100 is idle will be described.

  In step (hereinafter step is abbreviated as S) 100, ECU 1000 determines whether engine 100 is in an idle state or not. For example, when the accelerator opening is 0 during operation of engine 100, it is determined that engine 100 is in an idle state. If engine 100 is in an idle state (YES in S100), the process proceeds to S102. If not (NO in S102), the process proceeds to 116.

  In S102, ECU 1000 detects the throttle opening (idle throttle opening) during idling based on the signal transmitted from throttle position sensor 2010. In S104, ECU 1000 detects engine speed NE based on the signal transmitted from engine speed sensor 400.

  In S106, ECU 1000 calculates idle power based on the idle throttle opening and the current engine speed NE. In S108, ECU 1000 detects turbine rotational speed NT based on the signal transmitted from turbine rotational speed sensor 410.

  In S110, ECU 1000 calculates fully closed engine torque T (3) based on idle throttle opening and turbine speed NT. In S112, ECU 1000 calculates fully closed engine rotation based on the idle throttle opening and turbine rotational speed NT.

  In S114, ECU 1000 calculates minimum torque T (2) based on idle power and fully closed engine rotation. In S116, ECU 1000 determines whether or not minimum torque T (2) and fully closed engine torque T (3) have been calculated. Whether or not the minimum torque T (2) and the fully closed engine torque T (3) are calculated is based on a flag that is set when the minimum torque T (2) and the fully closed engine torque T (3) are calculated. Determined. If minimum torque T (2) and fully closed engine torque T (3) are calculated (YES in S116), the process proceeds to S118. If not (NO in S116), the process returns to S100.

  In S 118, ECU 1000 detects the accelerator opening based on the signal transmitted from accelerator opening sensor 2000. In S120, ECU 1000 calculates the throttle opening based on the detected accelerator opening.

  In S122, ECU 1000 calculates required torque T (1) for engine 100 based on the calculated throttle opening and turbine rotational speed NT. In S124, ECU 1000 corrects required torque T (1) by adding torque obtained by subtracting fully closed engine torque T (3) from minimum torque T (2) to required torque T (1). Then, a correction request torque T (4) is calculated.

  An operation of ECU 1000 of the control device according to the present embodiment based on the above-described structure and flowchart will be described.

  When the accelerator opening is set to 0 during operation of engine 100 and engine 100 is in the idle state (YES in S100), the throttle opening at idling (idle) is determined based on the signal transmitted from throttle position sensor 2010. The throttle opening is detected (S102). Further, the engine speed NE is detected based on the signal transmitted from the engine speed sensor 400 (S104). The idle power is calculated based on the detected idle throttle opening degree and the current engine speed NE (S106).

  Further, the turbine speed NT is detected based on the signal transmitted from the turbine speed sensor 410 (S108), and the fully closed engine torque T (3) is calculated based on the idle throttle opening and the turbine speed NT. (S110). Further, the fully closed engine speed is calculated based on the idle throttle opening degree and the turbine speed NT (S112).

  The calculated fully closed engine rotation is transmitted to the engine ECU 1020, and the engine ECU 1010 calculates the minimum torque T (2) based on the idle power and the fully closed engine rotation (S114). The calculated minimum torque T (2) is transmitted to the ECT_ECU 1020.

  When minimum torque T (2) and fully closed engine torque T (3) are calculated (YES in S116), the accelerator opening is detected based on the signal transmitted from accelerator opening sensor 2000 (S118). Based on this accelerator opening, the throttle opening is calculated (S120).

  Based on the calculated throttle opening and the turbine speed NT, a required torque T (1) to the engine 100 is calculated (S122). The required torque T (1) is corrected by adding the torque obtained by subtracting the fully closed engine torque T (3) from the minimum torque T (2) to the required torque T (1), and the corrected required torque T (4) ) Is calculated (S124). As a result, as shown in FIGS. 4 and 5, the correction required torque T (4) and the minimum torque T (2) when the accelerator opening is 0 can be matched.

  As shown in FIG. 4, when minimum torque T (2)> fully closed engine torque T (3) (required torque T (1) at accelerator opening 0), required torque T (1) before correction is When the engine 100 is used to control, the required torque T (1) and the minimum torque T (2) do not match until the accelerator opening becomes TA (1). Therefore, the torque generated by engine 100 does not change until the accelerator opening becomes TA (1). That is, there is a dead zone where the acceleration of the vehicle does not increase even if the accelerator opening increases with the driver's accelerator operation.

  On the other hand, when the engine 100 is controlled based on the correction required torque T (4) as in the present embodiment, the torque generated by the engine 100 due to the driver's accelerator operation is the minimum torque T (2). Ascend quickly. Thereby, a vehicle can be accelerated as a passenger | crew's request | requirement. Therefore, it is possible to suppress a sense of discomfort given to the passenger.

  Further, as shown in FIG. 5, when the minimum torque T (2) <the fully closed engine torque T (3) (the required torque T (1) at the accelerator opening 0), the required torque T (1 before correction) ) Is used to control the engine 100, and when the engine 100 is not in an idle state, the torque generated by the engine 100 suddenly changes stepwise from the minimum torque T (2) to the required torque T (1). . That is, when the accelerator opening increases with the driver's accelerator operation, the vehicle may accelerate rapidly and the driver may feel a shock.

  On the other hand, when the engine 100 is controlled based on the correction required torque T (4) as in the present embodiment, the torque generated by the engine 100 due to the driver's accelerator operation is the minimum torque T (2). Rise from. Thereby, it is possible to suppress a sudden change in the torque generated by engine 100. The shock given to the passenger can be suppressed.

  As described above, the ECU of the control device according to the present embodiment calculates the throttle opening based on the accelerator opening, and calculates the required torque T (1) to the engine based on the calculated throttle opening. calculate. Further, the ECU calculates the fully closed engine torque T (3) based on the throttle opening set by the idle speed control instead of the throttle opening set from the accelerator opening. Further, the ECU calculates a minimum torque T (2) that is actually generated by the engine during idling. The torque obtained by subtracting the fully closed engine torque T (3) from the minimum torque T (2) is added to the required torque T (1), and the corrected required torque T (4) is calculated. As a result, when the idle opening is 0, that is, the correction request torque T (4) during idling can be matched with the minimum torque T (2). Therefore, when the accelerator opening is increased, it is possible to suppress the torque from changing or the torque from changing suddenly stepwise. As a result, the uncomfortable feeling given to the driver can be suppressed and the vehicle can be accelerated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a control block diagram of a vehicle equipped with a control device according to an embodiment of the present invention. It is a control block diagram of ECU of the control apparatus which concerns on embodiment of this invention. It is a flowchart which shows the control structure of the program performed by ECU of the control apparatus which concerns on embodiment of this invention. It is a figure (the 1) which shows required torque T (1) before and behind correction | amendment. FIG. 6 is a diagram (part 2) showing a required torque T (1) before and after correction.

Explanation of symbols

  100 engine, 200 torque converter, 210 lockup clutch, 220 pump impeller, 230 turbine impeller, 240 stator, 250 one-way clutch, 300 automatic transmission, 400 engine speed sensor, 410 turbine speed sensor, 420 output shaft rotation Number sensor, 1000 ECU, 1010 engine ECU, 1020 ECT_ECU, 2000 accelerator opening sensor, 2010 throttle position sensor.

Claims (2)

First setting means for setting the throttle opening based on the accelerator opening;
Second setting means for setting the throttle opening when the internal combustion engine is in an idle state;
A first required torque for the internal combustion engine is calculated based on the throttle opening set by the first setting means, and the internal combustion engine is calculated based on the throttle opening set by the second setting means. Means for calculating a second required torque to
Means for calculating an output torque of the internal combustion engine in the idle state;
Correction means for correcting the first required torque based on a deviation between the second required torque and the output torque;
And a control unit for controlling the internal combustion engine based on the corrected first required torque.   2. The control device for an internal combustion engine according to claim 1, wherein the correcting means includes means for adding a torque obtained by subtracting the second required torque from an idle torque to the first required torque.

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