JP4282151B2 - Engine control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine control device, and more particularly to an engine control device that obtains a target torque required for an engine according to a situation and performs engine control based on the target torque.
[0002]
[Prior art]
In recent years, in order to perform engine control more precisely in response to demands such as improving fuel efficiency, an actuator is connected to the throttle valve in place of the conventional mechanical type in which the throttle valve and the accelerator pedal are connected by a wire. A so-called electronically controlled throttle type engine that electronically controls the throttle opening has been put into practical use.
[0003]
According to this, the throttle valve can be opened and closed independently from the operation of the accelerator pedal. For this reason, an engine output target value to be output by the engine is set based on the accelerator pedal depression amount and the engine speed, etc. during traveling (non-idle driving region), and the fuel injection amount and the engine output target value are set according to the set engine output target value. Various techniques have been proposed for improving the responsiveness to the driver's required output by controlling the amount of intake air and obtaining good driving performance.
[0004]
Also in the idle control in the idle operation region, as disclosed in Japanese Patent Laid-Open No. 7-197828, the output torque estimated from the engine speed and the throttle opening, and the load torque required for the drive during the external load drive A technique has been proposed in which the target output torque is calculated from the engine speed and the throttle opening is controlled from the engine speed and the target output torque.
[0005]
[Problems to be solved by the invention]
However, the above-described technology performs control according to the engine output target value set for each idle operation region or non-idle operation region, and the continuous output torque can be obtained only by combining the above two technologies. There is a risk that the smoothness and drivability on driving feeling at the time of shifting to the driving region when shifting from the non-idling driving region to the idling driving region or from the idling driving region to the non-idling driving region may be impaired.
[0006]
The present invention has been made in view of the above-described points, and its purpose is to ensure the continuity of the output torque at the time of transition to the operation region between the idle operation region and the non-idle operation region. It is an object of the present invention to provide an engine control device that improves the smoothness and drivability of the engine.
[0007]
[Means for Solving the Problems]
  In order to solve the above-described problem, an engine control apparatus according to the first aspect of the present invention includes a driver request torque calculation unit that calculates a driver request torque required for an engine from an engine speed and a depression amount of an accelerator pedal; Idle determination means for determining whether the operation region is an idle operation region or a non-idle operation region, and an idle control torque calculation for calculating an idle control torque necessary for maintaining the engine speed at the target idle speed Means, a basic base torque calculating means for obtaining a basic base torque by adding the driver required torque and the idle control torque, and a weighted average torque calculating means for calculating a weighted average torque by weighted averaging the basic base torque. And the engine operating state is not idle from the idle operating range. Region, or if the operating region when moving from the non-idle operation region in the idle operation region is the first time the program cycles after shifting from the non-idle operation region idling region, the operating regionNonIdle operation areaRahCalculate the correction torque at the time of transition by subtracting the basic base torque when the operation region has shifted from the non-idle operation region to the idle operation region from the weighted average torque calculated during the program cycle immediately before the transition to the idle operation region, In the case where there is a shift-time correction torque in the second and subsequent program cycles after the operation region shifts from the non-idle operation region to the idle operation region, a preset idle torque reduction is performed from the existing shift-time correction torque. A transition correction torque calculating means for calculating a new transition correction torque by subtracting the value, and a final target torque to be finally output to the engine based on the driver request torque, the idle control torque, and the transition correction torque. A final target torque calculating means for calculating, based on the final target torque And performing engine control.
[0008]
According to this, since the final target torque is calculated based on the driver request torque, the idle control torque, and the transition correction torque, the engine control based on the unified final target torque in all operation regions. It can be performed.
[0009]
  Therefore, the continuity of the output torque from the idle operation region to the non-idle operation region or from the non-idle operation region to the idle operation region can be ensured, and the smoothness in driving feeling can be improved. In addition, a simple and high-performance control system can be constructed, and costs can be reduced.Further, the correction torque at the time of transition is set at the first program cycle when transitioning from the non-idle operation region to the idle operation region, and is decreased by the idle torque reduction value at each subsequent program cycle. When shifting from the region to the idle operation region, it is possible to prevent deterioration of engine stall and operation feeling due to a rapid decrease in engine speed, and smooth connection of output torque can be realized.
[0015]
  Claim2In the engine control apparatus according to the invention, the shift correction torque calculation means calculates when the shift correction torque calculated when the operation region is the first program cycle after the operation region shifts from the non-idle operation region to the idle operation region. When it is larger than the preset upper limit torque value, the shift correction torque is changed to a value equal to the upper limit torque value.
[0016]
According to this, the transition correction torque in the first program cycle has an upper limit torque value as an upper limit, and gradually decreases from the upper limit torque value by executing the second and subsequent program cycles. Therefore, the output torque can be reduced at an appropriate speed, and the driving feeling can be improved when the operating region shifts from the non-idle operating region to the idle operating region.
[0017]
  Claim3In the engine control device according to the invention, the shift correction torque calculating means is configured such that when the shift correction torque exists when the operation region shifts from the idle operation region to the non-idle operation region, the drive region is the idle operation region. The shift correction torque calculated during the program cycle immediately before shifting to the non-idle operation region is set as the shift correction torque of the initial program cycle.
[0018]
When the operation region shifts from the idle operation region to the non-idle operation region for the second and subsequent program cycles and there is a transition correction torque, a non-set value that is set in advance from the existing transition correction torque. A new transition correction torque is calculated by subtracting the idle torque reduction value.
[0019]
According to this, when there is a transition correction torque when the operation region shifts from the idle operation region to the non-idle operation region, the existing transition correction torque is set as the transition correction torque in the first program cycle. Therefore, the continuity of the output torque can be ensured, and the feeling of deceleration before and after the transition from the idle operation region to the non-idle operation region, so-called breathing, can be prevented. As a result, smoothness can be ensured even when the operation region moves between the idle operation region and the non-idle operation region at short intervals.
[0020]
  Claim4In the engine control device according to the invention described above, the shift correction torque calculation means sets the non-idle torque reduction value according to the change amount of the basic base torque. According to this, since the shift correction torque is reduced according to the change amount of the basic base torque according to the change amount of the basic base torque, it is reduced according to the output torque requested by the operator who operates the accelerator pedal. Can be made.
[0021]
  Claim5In the engine control apparatus according to the invention, the idle control torque calculating means includes basic idle control torque setting means for setting basic idle control torque for maintaining the target idle speed, target idle speed and actual engine speed. Feedback control torque setting means for setting feedback control torque for feedback control of the engine speed to the target idle speed from the rotation deviation from the engine speed, and a torque correction amount for correcting the output torque consumed during idle operation And a torque correction amount setting means for setting the idle control torque, and calculating the idle control torque based on the basic idle control torque, the feedback control torque, and the torque correction amount.
[0022]
According to this, the idle control torque is calculated based on the basic idle control torque, the feedback control torque, and the torque correction amount, the basic idle control torque is set according to the operating conditions during idle operation, and the feedback control torque is the target The torque correction amount is set based on the consumption torque consumed by physical conditions such as engine accessories and friction, and is set based on the rotational deviation between the idle speed and the actual engine speed. For this reason, the engine speed can be quickly and accurately converged to and maintained at the target idle speed.
[0023]
  Claim6Engine according to the invention described incontrolIn the apparatus, the torque correction amount setting means corrects the engine friction torque set according to the engine speed based on the engine water temperature, so that a small torque correction amount at a low rotation and a large torque correction amount at a high rotation It is characterized by setting. According to this, the torque correction amount can be obtained by correcting the friction torque using the engine water temperature. For this reason, the torque correction amount can be set according to the correction feature, and the engine speed during idling can be stabilized.
[0024]
  Claim7Engine according to the invention described incontrolThe apparatus is characterized by setting a small torque correction amount at a low rotation and a large torque correction amount at a high rotation by correcting the engine friction torque set according to the engine speed based on the engine water temperature. . According to this, the torque correction amount can be obtained by correcting the friction torque using the engine water temperature. For this reason, the torque correction amount can be set according to the correction feature, and the engine speed during idling can be stabilized.
[0025]
  Claim8In the engine control apparatus according to the invention, the feedback control torque calculation means calculates the proportional control torque value and the integral control torque value from the rotation deviation between the target idle speed and the actual engine speed, and calculates the proportional The feedback control torque is obtained based on the control torque value and the integral control torque value.
[0026]
According to this, the feedback control torque is calculated using the proportional control torque value and the integral control torque value, and the feedback control is performed based on this, so that the convergence of the engine speed to the target idle speed is improved. Can be improved.
[0027]
  Claim9In the engine control apparatus according to the invention, the feedback control torque calculation means changes the integral control torque value according to the engine load during the idling operation. According to this, the convergence property to the target idle speed after the engine load changes can be improved.
[0028]
  Claim10In the engine control apparatus according to the invention, the feedback control torque calculation means learns the integral control torque value when a preset learning condition is satisfied, and uses the learned integral control torque value to provide the feedback control torque. Is calculated. According to this, since the feedback control torque is calculated using the learned integral control torque value, the convergence to the target idle speed can be further improved.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram conceptually showing an engine apparatus provided with an engine control apparatus of the present invention. The engine body 2 used in the engine device 1 is a horizontally opposed engine for automobiles, and is a cylinder injection engine that directly injects fuel into a cylinder. The engine device 1 includes an automatic transmission (not shown).
[0030]
The engine body 2 includes a cylinder block 3 that rotatably supports the crankshaft at a substantially central position thereof, and cylinder heads 4 in both the left and right banks of the cylinder block 3. An intake port 5 and an exhaust port 6 are formed in the cylinder head 4. An intake pipe 7 is connected to the intake port 5, and an exhaust pipe 8 is connected to the exhaust port 6.
[0031]
The intake pipe 7 constitutes a downstream portion of the intake passage 10, and an air cleaner box 11 and a throttle valve 12 are provided in the upstream portion of the intake passage 10. The throttle valve 12 is provided with a throttle actuator 13 that changes the valve opening based on a control signal from an electronic control unit described later.
[0032]
On the other hand, the exhaust pipe 8 constitutes an upstream portion of the exhaust passage 20, and a catalytic converter 21 such as a three-way catalyst for purifying exhaust gas and a muffler 22 are provided downstream thereof.
[0033]
Further, the exhaust pipe 8 and the collecting portion of the intake pipe 7 are communicated with each other by an EGR passage 23. In the middle of the passage, opening / closing control is performed using a stepping motor as a driving source, and the flow passage area of the EGR passage 23 is changed. An EGR valve 24 is provided.
[0034]
The cylinder head 4 is provided with a spark plug 26 and an injector 27 facing the combustion chamber. The spark plug 26 is supplied to the air-fuel mixture in the combustion chamber by the high voltage supplied through the igniter 28 and the ignition coil 29. Force ignition at a predetermined ignition timing. The injector 27 has a fuel injection direction directed toward the piston, atomizes the fuel pressure-supplied and supplied from the fuel pump 30 through the fuel pipe, and directly injects the fuel into the combustion chamber.
[0035]
The engine body 2, the intake passage 10, and the exhaust passage 20 are provided with various sensors for detecting the engine operating state. Specifically, the engine body 2 is provided with a crank angle sensor 31 that detects the rotation angle of the crankshaft and a water temperature sensor 32 that detects the temperature of the engine coolant.
[0036]
In the intake passage 10, there are an air flow meter 35 for detecting the intake air amount of the engine, an intake air temperature sensor 37 for detecting the gas temperature Tm in the intake pipe 7, and an intake pressure sensor 38 for detecting the intake pressure Pm in the intake pipe 7. Is provided. The exhaust passage 20 includes an exhaust temperature sensor 41 that detects the exhaust gas temperature, and an O / F for air-fuel ratio feedback control.₂A sensor 42 is provided.
[0037]
Further, in order to detect the engine operating state, an accelerator opening sensor 43 that outputs a voltage signal corresponding to the amount of depression of an accelerator pedal (not shown) is provided. In addition, the description of members that are not directly related to the function of the present invention among the members shown in the figure is omitted.
[0038]
The detection signals from the sensors are input to an electronic control unit (hereinafter simply referred to as ECU) 50, and a drive control signal is output from the ECU to each member. FIG. 2 is a schematic configuration explanatory diagram of the ECU 50. The ECU 50 is configured around a microcomputer, and as shown in the figure, a CPU 51, a ROM 52, a RAM 53, a backup RAM 54, a counter / timer 55, an input port 56, and an output port 57 are connected to each other via a bus line 58. .
[0039]
Also, an A / D converter 59 that converts analog signals received from various sensors into digital signals and delivers them to an input port, and a control signal received from an output port for converting to drive signals and outputting them to various actuators. A drive circuit 60 is incorporated.
[0040]
A crank angle sensor 31, an idle switch 44, and a selector position switch 46 are connected to the input port 56, and an air flow meter 35, an intake air temperature sensor 37, an exhaust gas temperature sensor 41, O are connected via an A / D converter 59.₂A sensor 42, an accelerator opening sensor 43, a vehicle speed sensor 45, and a selector position switch 46 are connected.
[0041]
The idle switch 44 outputs an OFF signal when the accelerator pedal is depressed, and outputs an ON signal when the accelerator pedal is released. The selector position switch 46 detects whether the range position of the automatic transmission is a drive range or a neutral range. Is. An igniter 28 is connected to the output port, and an injector 27, a throttle actuator 13, and an EGR valve 24 are connected via a drive circuit.
[0042]
The ROM 52 stores control programs and preset fixed data, the RAM 53 stores detection signals from various sensors, the backup RAM 54 stores learning data, etc., and the counter / timers 55 include time and the like. Measure. The CPU 51 performs arithmetic processing according to a control program stored in the ROM 52 using preset fixed data and detection signals from various sensors, and performs fuel injection control, ignition timing control, and the like.
[0043]
That is, by means of the ECU 50 and the sensors and actuators connected to the ECU 50, the driver required torque calculating means M1, the idle control torque calculating means M2, the transition correction torque calculating means M3, the final target torque calculating means M4, the idle Each function of determination means M5, fuel / intake / EGR setting means M6, and other control functions are realized.
[0044]
Next, engine control processing executed by the ECU will be described with reference to FIG. FIG. 3 is a control block diagram illustrating a control processing unit formed in the ECU. The control processing unit includes driver request torque calculation means M1, idle control torque calculation means M2, transition correction torque calculation means M3, final target torque calculation means M4, idle determination means M5, and fuel / intake / EGR setting means M6.
[0045]
The driver required torque calculation means M1 outputs an output torque (hereinafter referred to as driver required torque) requested by the driver (vehicle operator) to the engine based on the accelerator opening S that is the amount of depression of the accelerator pedal and the engine speed Ne. Calculate TEIM.
[0046]
The idle control torque calculation means M2 calculates an output torque (hereinafter referred to as idle control torque) ISCTQF necessary for maintaining the engine speed Ne at the target idle speed Nset.
[0047]
The correction torque calculation means M3 at the time of transition is an output torque (in order to ensure the continuity of the output torque when the operation state shifts from the idle operation region to the non-idle operation region, or from the non-idle operation region to the idle operation region). TRKTQ (hereinafter referred to as a correction torque at the time of transition) is calculated based on the driver request torque TEIM and the idle control torque ISCTQF.
[0048]
The idle determination means M5 determines whether or not the engine is idling based on the accelerator opening S and the engine speed Ne.
[0049]
The final target torque calculation means M4 calculates an output torque (hereinafter referred to as final target torque) TEI that is finally output by the engine based on the driver request torque TEIM, the idle control torque ISCTQF, and the transition correction torque TRKTQ.
[0050]
The fuel / intake / EGR setting means M6 is a fuel injection amount required for the engine to output the final target torque TEI based on the final target torque TEI, the intake pipe pressure Pm, the intake air temperature Tm, and the intake air amount average value Qave. Gf, intake air amount Qa, and EGR amount Qe are set, and the respective control amounts are output to the injector 27, the throttle actuator 13, and the EGR valve 24, respectively. The configuration and internal processing of the fuel / intake / EGR setting means M6 are described in detail in Japanese Patent Application Laid-Open No. 11-82100 already filed by the applicant of the present application, and therefore the description thereof is omitted in the present application. .
[0051]
Next, a method for calculating the final target torque TEI will be described below using a flowchart. FIG. 4 is a flowchart showing a final target torque calculation routine. First, in step S1, a driver request torque TEIM is obtained. The driver request torque TEIM is obtained based on the accelerator opening S, which is the depression amount of the accelerator pedal, and the engine speed Ne. Specifically, it is obtained by referring to a data map for calculating the required driver torque preset in the ROM with interpolation calculation using the accelerator opening S and the engine speed Ne.
[0052]
Next, in step S2 and step S3, an idle control torque ISCTQF and a transition correction torque TRKTQ are obtained, respectively. A method for calculating the idle control torque ISCTQF and the transition correction torque TRKTQ will be described later. In step S4, a final target torque calculation TEI is obtained. The final target torque calculation TEI is obtained by the following equation (1).
[0053]
TEI = TEIM + ISCTQF + TRKTQ (1)
That is, the final target torque TEI is obtained by adding the driver request torque TEIM, the idle control torque ISCTQF, and the transition correction torque TRKTQ. Based on the final target torque TEI, the fuel / intake / EGR setting means M6 sets the fuel injection amount Gf, the intake air amount Qa, and the EGR amount Qe, and controls the injector 27, the throttle actuator 13, and the EGR valve 24. A signal is output to each actuator.
[0054]
Therefore, engine control is performed based on the unified final target torque TEI for all the operation regions of the idle operation region and the non-idle operation region. Thereby, the continuity of the output torque between the idle operation region and the non-idle operation region can be ensured, and the smoothness in driving feeling can be improved. In addition, a simple and high-performance control system can be constructed, and costs can be reduced.
[0055]
Next, the calculation process of the idle control torque ISCTQF in step S2 will be described. FIG. 5 is a flowchart showing a routine for calculating the idle control torque ISCTQF. This routine is executed in a program cycle at predetermined intervals.
[0056]
The idle control torque ISCTQF is the feedback control torque FBKTQ obtained in steps S11 to S15, the basic torque correction amount KGKTQ, the auxiliary device torque correction amount KWBTQ, the other torque correction amount KXTQn during idling, and the idle control torque learning value ISCTQL. Is calculated in step S16. The idle control torque ISCTQF is calculated by the following equation (2).
[0057]
ISCTQF = FBKTQ + KGKTQ + KWBTQ + KXTQn + ISCTQL ...... (2)
That is, the idle control torque ISCTQF is obtained by adding the feedback control torque FBKTQ, the basic torque correction amount KGKTQ, the auxiliary machinery torque correction amount KWBTQ, the other torque correction amount KXTQn during idling, and the idle control torque learning value ISCTQL. Desired.
[0058]
Here, the basic torque correction amount KGKTQ is obtained by correcting the engine friction torque set in advance according to the engine speed based on the engine water temperature detected by the water temperature sensor 32, and a small torque correction amount at low speed. A large torque correction amount is set during high rotation.
[0059]
Auxiliary machinery torque correction amount KWBTQ is obtained by correcting the known rated output of engine auxiliary machinery based on the engine speed, and a large torque correction amount at low speed and a small torque correction amount at high speed. Is set. The other torque correction amount KXTQn during idling is obtained based on the post-startup torque correction amount, the gear position torque correction amount, the learning torque correction amount, and the like.
[0060]
As described above, these basic torque correction amount KGKTQ, auxiliary machinery torque correction amount KWBTQ, and other torque correction amounts KXTQn during idling are set in accordance with correction characteristics such as output torque or rated output, respectively.
[0061]
Further, the feedback control torque FBKTQ is set according to the target idle speed Nset, and the idle control torque learning value ISCTQL is learned in the backup RAM 54 of the ECU 50 when a predetermined learning condition is satisfied, and is read when the engine is started. It is.
[0062]
FIG. 6 is a routine for calculating the feedback control torque FBKTQ. This routine is executed in a program cycle at predetermined intervals. First, in step S21, the target idle speed Nset is set. The target idle speed Nset is set according to the engine operating conditions, for example, the warm-up state. In step S22, the rotational deviation DELTAN is calculated using the target idle speed Nset set in step S21 and the actual engine speed Ne directly detected by the crank angle sensor.
[0063]
In step S23, a proportional control torque value PROEID that is a proportional component of the feedback control torque FBKTQ is calculated based on the rotational deviation DELTAN obtained in step S22. Specifically, the proportional control torque value PROEID is calculated by the following equation (3).
[0064]
PROEID = IDKPK × IDKP_HL × DELTAN ...... (3)
As shown in the above equation (3), the proportional control torque value PROEID is obtained by multiplying the rotation deviation DELTAN by the rotation correction coefficient IDKPK and the proportional control torque coefficient IDKP_HL. The rotation correction coefficient IDKPK and the proportional control torque coefficient IDKP_HL (proportional gain) are values set in advance in the ROM of the ECU.
[0065]
Next, in step S24, it is determined whether feedback control is being performed. Based on this determination, a method for calculating an integral control torque value CFBID that is an integral part of the feedback control torque FBKTQ is determined. If feedback control is being performed (YES), the process proceeds to step S25. If feedback control is not being performed (NO), the process proceeds to step S29.
[0066]
In step S25, an integral control torque value CFBIDI that is an integral part of the feedback control torque FBKTQ is calculated based on the rotation deviation DELTAN obtained in step S22. Specifically, it is obtained by the following equation (4).
[0067]
CFBIDI = IDKIK × IDKI_HL × DELTAN × dt ...... (4)
As shown in the above equation (4), the integral control torque value CFBIDI is obtained by multiplying the rotation deviation DELTAN by the rotation correction coefficient IDKIK and then integrating over time. Thereby, hunting of the integral control torque value can be prevented when the engine speed changes.
[0068]
Then, the process proceeds to step S26 in order to make the integral control torque value CFBIDI obtained by the above equation (4) according to the engine load and the engine speed. In step S26, it is determined from the output of the selector position sensor 46 whether the position of the selector lever (both not shown) of the automatic transmission is in the drive range (D range) or the neutral range (N range). This is because the load applied to the engine or the engine speed Ne is different between the D range and the N range, and the integral control torque value CFBID corresponding to this is set.
[0069]
Here, when the range position of the selector lever is the N range (NO), the process proceeds to step S27, and in step S27, the N range integral control torque value CFBID_N._nIs obtained by the following equation (5).
[0070]
CFBID_N_n= CFBIDI + CFBID_N_n-1              ……(Five)
According to the above equation (5), the N range integral control torque value CFBID_N obtained during the previous program cycle is added to the integral control torque value CFBIDI obtained by equation (4) in step S25._n-1Is obtained by adding.
[0071]
If the selector lever range position is in the D range (YES) in step S26, the process proceeds to step S28, and in step S28, the D range integral control torque value CFBID_D._nIs calculated. Specifically, it is obtained by the following equation (6).
[0072]
CFBID_D_n= CFBIDI + CFBID_D_n-1              …… (6)
According to the above equation (6), the D range integral control torque value CFBID_D previously obtained in step S25 is added to the integral control torque value CFBIDI obtained by equation (4)._n-1Is obtained by adding.
[0073]
Thus, N range integral control torque value CFBID_N_nAnd D range integral control torque value CFBID_D_nIs calculated according to the position of the selector lever, and the convergence of the engine speed Ne to the target engine speed Nset in the feedback control can be improved.
[0074]
On the other hand, if it is determined in step S24 that the feedback control is not performed (NO), the process proceeds to step S29. In step S29, control is performed to hold the previous value of the integral control torque value. For the N range, the following equation (7) is obtained. For the D range, the following equation (8) is obtained.
[0075]
CFBID_N_n= CFBID_N_n-1 ...... (7)
CFBID_D_n= CFBID_D_n-1 ...... (8)
As a result, the integral control torque value CFBID is held during idle operation open loop control and when the idle switch is OFF. In step S30, a calculation process for obtaining the feedback control torque FBKTQ is performed. The feedback control torque FBKTQ is obtained by the following equation (9).
[0076]
FBKTQ = PROEID + CFBID ...... (9)
As shown in the above equation (9), the feedback control torque FBKTQ is obtained by adding the proportional control torque value PROEID obtained in step S23 and the integral control torque value CFBID obtained in steps S24 to S29.
[0077]
FIG. 7 is a flowchart showing a learning routine program for the idle control torque learning value ISCTQL. This routine is executed in a program cycle at predetermined intervals. First, in step S31, it is determined whether a learning condition is satisfied. If the learning condition is satisfied (YES), the process proceeds to step S32, where it is determined whether the ignition key for starting the engine has been switched from ON to OFF.
[0078]
Then, when the ignition key is switched from ON to OFF (YES), the process proceeds to step S33 in order to learn the idle control torque ISCTQL. In step S33, the idle control torque learning value when the ignition key is switched from ON to OFF (hereinafter referred to as the OFF switching integral control torque learning value) ISCTQLX_nIs calculated. Specifically, it is obtained by the following equation (10).
[0079]
ISCTQLX_n= ((CFBID + ISCTQLO) / CTISL) + ISCTQLX_n-1 ……(Ten)
In other words, OFF control integral control torque learning value ISCTQLX_nIs calculated by adding the integral control torque value CFBID and the idle control torque learning value offset value ISCTQLO, and then dividing by the number of learning executions CTISL._n-1It is calculated by adding. Here, the number of learning executions CTISL is a value equal to or less than the set number of times ISLCT, which is incremented by one every time the learning calculation ends.
[0080]
In step S34, the OFF control integral control torque learning value ISCTQLX_nIs determined to be smaller than a preset minimum value ISCTQLXmin. Here, if it is smaller than the minimum value ISCTQLXmin (YES), the process proceeds to step S35, and the integral control torque learning value ISCTQLX at OFF switching at step S35._nIs made equal to the above-mentioned minimum value ISCTQLXmin. Then, this OFF switching integral control torque learning value ISCTQLX_nIn order to obtain the idle control torque learning value ISCTQL using, the process proceeds to step S38.
[0081]
If the value is equal to or greater than the minimum value (NO), the process proceeds to step S36, and the integral control torque learning value ISCTQLX at the time of OFF switching in step S36._nIt is determined whether or not is greater than a preset maximum value ISCTQLXmax. Here, when it is larger than the maximum value ISCTQLXmax (YES), the process proceeds to step S37, and the integral control torque learning value ISCTQLX at OFF switching at step S37._nIs changed to a value equal to the aforementioned maximum value ISCTQLXmax.
[0082]
If it is smaller than the maximum value ISCTQLXmax (NO) in step S36, this OFF switching integration control torque learning value ISCTQLX_nIn order to obtain the idle control torque learning value ISCTQL using, the process proceeds to step S38.
[0083]
In step S38, the integral control torque learning value ISCTQLX at OFF switching_nIs greater than 0 (YES), the process proceeds to step S39, and the idle control torque learning value ISCTQL corresponding to the predetermined condition is calculated in step S39. Specifically, it is obtained by the following equation (11).
[0084]
ISCTQL = ISCTQLX_n× TWISL …… (11)
According to this, integral control torque learning value ISCTQLX at OFF switching_nIs multiplied by the correction value TWISL. Here, the correction value TWISL is obtained by referring to the lattice table TISLTW set in advance in the ROM with interpolation calculation based on the engine coolant temperature detected by the water temperature sensor 32.
[0085]
If it is determined in step S38 that the value is not greater than 0 (NO), the process proceeds to step S40, and the idle control torque learning value ISCTQL is calculated in step S40. Specifically, it is obtained by the following equation (12).
[0086]
ISCTQL = ISCTQLX …… (12)
In other words, integral control torque learning value ISCTQLX when switching when OFF_nThis is the idle control torque learning value ISCTQL. As described above, after the idle control torque learning value ISCTQL is obtained according to a predetermined condition, the routine is exited (return).
[0087]
If the learning condition is not satisfied in step S31 (NO), and if the ignition key is not switched from ON to OFF in step S32 (NO), learning of the idle control torque learning value ISCTQL is performed. Exit this routine (return) as not being performed. Therefore, the idle control torque learning value ISCTQL is learned by the learning routine described above, and is read when calculating the idle control torque ISCTQF. As described above, the idle control torque ISCTQF is calculated in step S16 of FIG. As a result, by using the idle control torque learning value ISCTQL during the idle control torque ISCTQF, it is possible to improve the convergence of the engine speed to the target idle speed when the engine is started.
[0088]
Next, the process for calculating the transition correction torque TRKTQ performed in step S3 of FIG. 4 will be described. FIG. 8 is a flowchart showing a routine for calculating the transition correction torque TRKTQ, and FIG. 9 is a time chart for explaining the relationship between the basic base torque TEI1 and the transition correction torque TRKTQ. This routine is executed in a predetermined program cycle.
[0089]
Steps S41 to S51 in FIG. 8 show calculation processing when the operation region shifts from the non-idle operation region to the idle operation region. In step S41, it is determined whether or not the idle switch outputs an ON signal. If the idle switch outputs an ON signal (YES), it is determined that the operation region is within the idle operation region. Proceed to S42. If the idle switch outputs an OFF signal (NO), it is determined that the idle switch is not in the idle operation region, and the process proceeds to step S52.
[0090]
In step S42, it is determined whether or not the current program cycle is the first program cycle after the OFF signal of the idle switch is changed to the ON signal (hereinafter referred to as OFF / ON initial program cycle). As a result, it is determined whether to calculate a new transition correction torque TRKTQ and perform control based on it or to perform control based on the already set transition correction torque TRKTQ. Here, when it is the OFF / ON initial program cycle (YES), the process proceeds to step S43 and subsequent steps in order to calculate a new shift correction torque TRKTQ.
[0091]
In step S43 to step S45, a process for calculating the shift correction torque during the initial OFF / ON program cycle is performed. In step S43, a temporary calculation of the shift correction torque TRKTQ is performed. The transition correction torque TRKTQ is the initial basic base torque TEI1._nAnd weighted average torque TEI1_KAV_n-KOLD1Based on the above, it is calculated by the following equation (13).
[0092]
TRKTQ = TEI1_KAV_n-KOLD1-TEI1_n ……(13)
Here, the initial basic base torque TEI1_nIs a value in the initial OFF / ON program cycle of the basic base torque TEI1 obtained by adding the driver request torque TEIM and the idle control torque ISCTQF. Also, the weighted average torque TEI1_KAV_n-KOLD1Is obtained by performing a weighted average process on the basic base torque TEI1.
[0093]
9A shows a change in the output signal of the idle switch, and FIG. 9B shows a change in the basic base torque TEI1 and the weighted average torque TEI1_KAV. The shift correction torque TRKTQ during the initial OFF / ON program cycle is the weighted average torque TEI1_KAV as shown in FIGS._n-KOLD1And initial basic base torque TEI1_nIn other words, the deviation between the torque before releasing the accelerator pedal and the torque after releasing.
[0094]
In step S44, it is determined whether or not the transition correction torque TRKTQ provisionally calculated in step S43 is greater than a preset dashpot torque DASHPOT (upper limit torque value). Here, if it is determined that the provisionally calculated shift correction torque TRKTQ is greater than the dashpot torque DASHPOT (YES), the process proceeds to step S45.
[0095]
In step S45, a process of setting the value of the dashpot torque DASHPOT as a new shift correction torque TRKTQnew is performed (TRKTQnew ← DASHPOT). Thereby, the upper limit of the shift correction torque is set.
[0096]
If it is determined in step S44 that the provisionally calculated transition correction torque TRKTQ is equal to or less than the dashpot torque DASHPOT (NO), the routine is exited (return). Therefore, the temporarily calculated shift correction torque TRKTQ is set as a new shift correction torque TRKTQnew. As described above, in step S42 to step S45, the transition correction torque TRKTQ in the OFF / ON initial program cycle is calculated.
[0097]
Next, a process for calculating the shift correction torque TRKTQ when it is not the OFF / ON initial program cycle will be described. If it is determined in step S42 that it is not the first OFF / ON program cycle (NO), it is determined that the current program cycle is a plurality of program cycles after the OFF signal of the idle switch changes to the ON signal. Then, the process proceeds to S46 and subsequent steps in order to calculate the correction torque TRKTQ at the time of transition.
[0098]
In steps S46 to S51, a new transition correction torque TRKTQnew is set according to various conditions. By this process, the shift correction torque TRKTQ is gradually reduced from the value set during the initial OFF / ON program cycle. (C) in FIG. 9 shows the change in the shift correction torque TRKTQ, and (d) in the figure shows the state of the decrease rate change flag.
[0099]
First, in step S46, it is determined whether or not the current transition correction torque TRKTQ is higher than a preset cushion value RDASH. Based on this determination, it is selected whether to make the reduction speed of the transition correction torque TRKTQ fast or slow.
[0100]
If the current transition correction torque TRKTQ is higher than the cushion value RDASH (YES), the process proceeds to step S47 in order to set a new transition correction torque TRKTQnew according to the determination. In step S47, a value obtained by reducing the preset first torque reduction value DDSH1 from the current transition correction torque TRKTQ is set as a new transition correction torque TRKTQnew (TRKTQnew ← TRKTQ-DDSH1). Then, this routine is exited (return).
[0101]
If the current transition correction torque TRKTQ is equal to or less than the cushion value RDASH in step S46 (NO), the process proceeds to step S48, and it is determined whether or not the decrease change rate flag is set in step S48. Is done. The decrease change rate flag determines whether the value (idle torque reduction value) for reducing the transition correction torque TRKTQ is adopted as the first torque reduction value DDSH1 or the second torque reduction value DDSH2 (DDSH1> DDSH2). It is a flag for.
[0102]
The decrease change rate flag is cleared when the idle switch is OFF as shown in (d) of the figure, and the engine speed Ne is equal to or less than the value obtained by adding the target engine speed Nset and the speed setting value Ndash. Alternatively, it is set when the vehicle speed V continues below the vehicle speed set value VDASH for the set time or longer after the transitional correction torque TRKTQ becomes equal to or lower than the cushion value RDASH.
[0103]
If it is determined in step S48 that the decrease change rate flag is set (YES), the process proceeds to step S49 to determine whether or not the shift correction torque TRKTQ has already disappeared. In step S49, it is determined whether or not the shift correction torque TRKTQ is zero. Thus, it is determined whether or not the transition correction torque TRKTQ set during the initial OFF / ON program cycle has already disappeared by the subsequent torque reduction process. If the transition correction torque TRKTQ is not 0 (NO), the process proceeds to step S50.
[0104]
In step S50, a process of updating a value obtained by reducing the preset second torque reduction value DDSH2 from the current transition correction torque TRKTQ as a new transition correction torque TRKTQnew is performed (TRKTQnew ← TRKTQ-DDSH2). . Then, this routine is exited (return). Further, when the change decrease ratio flag is clear in step S48 (NO), or when it is determined in step S49 that the shift correction torque TRKTQ is 0 (YES), the process proceeds to step S51.
[0105]
In step S51, the current transition correction torque TRKTQ is updated to a new transition correction torque TRKTQnew (TRKTQnew ← TRKTQ). Thereby, when the change reduction ratio flag is cleared in step S48 (NO), the transition correction torque TRKTQ is maintained at the cushion value RDASH until the flag is set. Further, when the shift correction torque TRKTQ is 0 (YES) in step S49, it is maintained at 0 as it is.
[0106]
Therefore, if the transition correction torque TRKTQ set during the initial OFF / ON program cycle is larger than the cushion value RDASH, the reduction is temporarily stopped at the cushion value RDASH in the process of decreasing, and the cushion value It is maintained for a predetermined time in RDASH, that is, until the decrease change rate flag is set, and then gradually decreased to 0. As a result, it is possible to prevent the engine rotational speed Ne from being lowered below the target idle rotational speed NSET due to a sudden drop in the output torque, and to ensure a smooth change in the output torque. Then, this routine is exited (return).
[0107]
According to the processing from step S42 to step S51 described above, the transition correction torque TRKTQ is obtained from the amount of torque change before and after the change from the OFF signal to the ON signal of the idle switch. Thereafter, it is gradually decreased. As a result, engine stall due to a sudden decrease in engine speed can be avoided, and deterioration in driving feeling can be prevented.
[0108]
Next, a method for calculating the transition correction torque TRKTQ when the operation region is shifted from the idle operation region to the non-idle operation region will be described. If the idle switch outputs an OFF signal in step S41 (NO), it is determined that the idle operation is not in progress, and the process proceeds to step S52. In step S52, the current program cycle is the ON signal of the idle switch. It is determined whether or not this is the first program cycle (hereinafter referred to as ON / OFF initial program cycle) after the signal changes to the OFF signal.
[0109]
Here, if it is the ON / OFF initial program cycle (YES), the process proceeds to step S53, and it is determined in step S53 whether or not the transitional correction torque TRKTQ is zero. As a result, when the operation region shifts from the idle operation region to the non-idle operation region, the transition correction torque TRKTQ that was previously set when the operation region transitioned from the non-idle operation region to the idle operation region is being reduced. It is determined whether it still exists.
[0110]
If the transition correction torque TRKTQ is not 0 (NO) in step S53, it is determined that the previously set transition correction torque TRKTQ still exists and the transition correction during the ON / OFF initial program cycle is determined. To calculate the torque TRKTQ, the process proceeds to step S54. In step S54, the transition correction torque TRKTQ set in the previous program cycle is set._n-1Is set to the new transition correction torque TRKTQ (TRKTQnew ← TRKTQ_n-1).
[0111]
FIG. 10 is an explanatory diagram for explaining the relationship between the basic base torque TEI1 and the transition correction torque TRKTQ when the accelerator pedal is changed from the non-depressed state to the depressed state. In the figure, (a) shows the change in the output signal of the idle switch, (b) shows the change in the basic base torque TEI1, (c) shows the change in the transition correction torque TRKTQ, and (d) in the figure. The change of the 3rd torque reduction value DDSH3 is shown.
[0112]
As shown in FIG. 10C, the transition correction torque TRKTQ is temporarily reduced by the processing of steps S53 and S54 in FIG. 8 at the same time when the idle switch changes from the ON signal to the OFF signal. After maintaining that value for a time, it is gradually reduced to zero. This prevents a feeling of deceleration before and after the change from the ON signal of the idle switch to the OFF signal, so-called breathing, and even when the change from the ON signal of the idle switch to the OFF signal is repeated in a short time. It is possible to ensure smoothness in driving feeling.
[0113]
Therefore, continuity of the output torque from the idle operation region to the non-idle operation region can be ensured, and drivability can be improved. Then, this routine is exited (return). If it is determined in step S53 that the shift correction torque TRKTQ is 0 (YES), the routine is exited (return).
[0114]
If it is determined in step S52 that the program cycle is not the ON / OFF initial program cycle (NO), the process proceeds to step S55 and subsequent steps in order to calculate the shift correction torque TRKTQ according to the conditions. In step S55, it is determined whether or not the transition correction torque TRKTQ is 0 as in step S53.
[0115]
As a result, it is determined whether or not the shift correction torque TRKTQ still exists. If the shift correction torque TRKTQ is not 0 (NO), it is determined that the previously set shift correction torque TRKTQ still exists, and the process proceeds to step S56.
[0116]
In step S56, the transition correction torque TRKTQ set in the previous program cycle is set._n-1The value obtained by subtracting the third torque reduction value (non-idle torque reduction value) DDSH3 from is processed as a new transition correction torque TRKTQ (TRKTQ ← TRKTQ_n-1-DDSH3). As a result, the shift correction torque TRKTQ is gradually decreased by the third torque reduction value DDSH3.
[0117]
FIG. 11 is a flowchart showing a routine for calculating the third torque reduction value DDSH3. First, in step S61, provisional calculation of the third torque reduction value DDSH3 is performed. Here, the third torque reduction value DDSH3 is the basic base torque TEI1 in the previous program cycle._n-1Basic base torque TEI1 during the previous program cycle_n-2Is calculated by subtracting (DDSH3 ← TEI1_n-1-TEI1_n-2).
[0118]
Thereby, the shift correction torque TRKTQ can be set in accordance with the change in the basic base torque TEI1. For example, when the basic base torque TEI1 increases rapidly, the value of the third reduced torque value DDSH3 increases, and the amount of decrease in the transition correction torque TRKTQ increases.
[0119]
In step S62, it is determined whether or not the third torque reduction value DDSH3 is 0 or more. Here, if it is 0 or more (YES), the third torque reduction value DDSH3 provisionally calculated in step S61 is adopted as it is, and this routine is exited (return). If it is smaller than 0 (NO), the process proceeds to step S63 in order to limit the minimum value of the third torque reduction value DDSH3. In step S63, the third torque reduction value DDSH3 is set to 0 (DDSH3 ← 0).
[0120]
According to the processing in step S56 described above, the transition correction torque TRKTQ is reduced by using the third torque reduction value that is set according to the amount of change in the basic base torque TEI1, and accordingly, according to the torque requested by the driver. Can be reduced. Therefore, driving feeling can be improved.
[0121]
As another method for calculating the shift correction torque TRKTQ when it is determined in step S52 that it is not the ON / OFF initial program cycle (NO), the following equation (14) may be used.
[0122]
TRKTQ_n= TRKTQ_n-1− (DDSH1 × DDSH3 + DDSH0) ...... (14)
According to the above equation (14), the transition correction torque TRKTQ_nIs obtained by multiplying the first torque reduction value DDSH1 and the third torque reduction value DDSH3 and adding a constant DDSH0, and obtaining the transition correction torque TRKTQ obtained in the previous program cycle._n-1Is obtained by subtracting from. As a result, a method for reducing the transition correction torque TRKTQ can be optimized, and higher smoothness in driving feeling can be ensured.
[0123]
As another method for calculating the shift correction torque TRKTQ when it is determined in step S52 that the program cycle is not the ON / OFF initial program cycle (NO), the first torque reduction value DDSH1 in the above-described equation (14) is used. The constant DDSH0 may be set to a value set for each operation region by the accelerator opening S and the engine speed. As a result, like the other examples described above, the method of reducing the transition correction torque TRKTQ can be further optimized, and higher smoothness in driving feeling can be ensured.
[0124]
If the shift correction torque TRKTQ is 0 (YES) in step S55, the process exits (return). Therefore, the shift correction torque TRKTQ can be calculated in step S3.
[0125]
【The invention's effect】
As described above, according to the engine control apparatus of the present invention, the final target torque is calculated based on the driver request torque, the idle control torque, and the transition correction torque. Engine control based on the unified final target torque can be performed.
[0126]
Therefore, the continuity of the output torque from the idle operation region to the non-idle operation region or from the non-idle operation region to the idle operation region can be ensured, and the smoothness in driving feeling can be improved. In addition, a simple and high-performance control system can be constructed, and costs can be reduced.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram conceptually showing an engine apparatus provided with an engine control apparatus of the present invention.
FIG. 2 is an explanatory diagram of a schematic configuration of an ECU.
FIG. 3 is a control block diagram for explaining a control processing unit formed in the ECU.
FIG. 4 is a flowchart showing a final target torque calculation routine.
FIG. 5 is a flowchart showing a routine for calculating an idle control torque ISCTQF.
FIG. 6 is a flowchart showing a routine for calculating feedback control torque FBKTQ.
FIG. 7 is a flowchart showing a routine for calculating an idle control torque learning value ISCTQL.
FIG. 8 is a flowchart showing a routine for calculating a shift correction torque TRKTQ.
FIG. 9 is an explanatory diagram for explaining a relationship between a basic base torque TEI1 and a transition correction torque TRKTQ.
FIG. 10 is an explanatory diagram for explaining a relationship between a basic base torque TEI1 and a transition correction torque TRKTQ.
FIG. 11 is a flowchart showing a calculation routine of a third torque reduction value DDSH3.
[Explanation of symbols]
1 Engine equipment
2 Engine body
14 ETC
24 EGR valve
27 Injector
37 Intake air temperature sensor
38 Intake pressure sensor
43 Accelerator position sensor
44 Idle switch
45 Vehicle speed sensor
46 Selector position switch
M1 Driver required torque calculation means
M2 idle control torque calculation means
M3 shift correction torque calculation means
M4 Final target torque calculation method
M5 idle determination means
M6 Fuel / Intake / EGR Setting Method
TEIM driver required torque
ISCTQF Idle control torque
TRKTQ transition correction torque
FBKTQ feedback correction torque
KGKTQ Basic torque correction amount
KWBTQ Auxiliary machine correction amount
KXTQn Other torque correction amount

Claims (10)

Driver request torque calculation means for calculating a driver request torque required for the engine from the engine speed and the amount of depression of the accelerator pedal;
Idle determination means for determining whether the engine operation region is an idle operation region or a non-idle operation region;
Idle control torque calculating means for calculating an idle control torque necessary for maintaining the engine speed at the target idle speed;
A basic base torque calculating means for calculating a basic base torque by adding the driver required torque and the idle control torque, and a weighted average torque calculating means for calculating a weighted average torque by weighted averaging the basic base torque; This is the first program cycle after the engine operating state shifts from the non-idle operating region to the idle operating region when the engine operating state shifts from the idle operating region to the non-idle operating region or from the non-idle operating region to the idle operating region. If, the main base torque when migrating the operating region from the weighted average torque calculated during the immediately preceding program cycle operating region shifts to the non-idle operation region or Raa idle operating region from the non-idle operation region in the idle operation region Is calculated by subtracting In the case where there is a shift-time correction torque in the second and subsequent program cycles after the region shifts from the non-idle operation region to the idle operation region, an idle torque reduction value set in advance from the existing shift-time correction torque A transition correction torque calculating means for calculating a new transition correction torque by subtracting
A final target torque calculating means for calculating a final target torque to be finally output to the engine based on the driver required torque, idle control torque, and transition correction torque, and
An engine control apparatus that performs engine control based on the final target torque. The shift correction torque calculation means includes:
When the correction torque at the time of transition when the operation region is the first program cycle after the transition from the non-idle operation region to the idle operation region is larger than the preset upper limit torque value,
The engine control device according to claim 1, wherein the shift correction torque is changed to a value equal to an upper limit torque value. The shift correction torque calculation means includes:
When there is a transition correction torque when the operating region transitions from the idle operating region to the non-idle operating region, the transition time calculated during the program cycle immediately before the operating region transitions from the idle operating region to the non-idle operating region Set the correction torque as the correction torque at the transition of the first program cycle,
If there is a transition-time correction torque in the second and subsequent program cycles after the operation region transitions from the idle operation region to the non-idle operation region, the non-idle torque preset from the existing transition-time correction torque the engine control apparatus according to claim 1 or 2, characterized in that to calculate the time correction torque new migration by subtracting the reduction value. The shift correction torque means is
The engine control device according to claim 3 , wherein the non-idle torque reduction value is set in accordance with a change amount of the basic base torque. The idle control torque calculating means includes
Basic idle control torque setting means for setting a basic idle control torque for maintaining the target idle speed;
Feedback control torque setting means for setting a feedback control torque for performing feedback control of the engine speed to the target idle speed from a rotational deviation between the target idle speed and the actual engine speed;
Torque correction amount setting means for setting a torque correction amount for correcting the output torque consumed during idle operation,
The basic idling control torque, and a feedback control torque, the torque correction amount and the engine control apparatus according to any one of claims 1 to 4, characterized in that for calculating the idling control torque based on. The torque correction amount setting means includes:
By correcting based on the known rated output of the engine auxiliary machinery of the engine speed, the low speed rotation large torque correction amount is, according to claim 5, at the time of high rotation and sets the small torque correction amount Engine control device. The torque correction amount setting means includes:
By correcting the engine friction torque set according to the engine speed based on the engine water temperature, a small torque correction amount is set at a low rotation and a large torque correction amount is set at a high rotation. The engine control device according to claim 5 or 6 . The feedback control torque calculating means includes
A proportional control torque value and an integral control torque value are calculated from a rotation deviation between the target idle speed and the actual engine speed, and a feedback control torque is obtained based on the calculated proportional control torque value and the integral control torque value. the engine control apparatus according to any one of claims 5-7, characterized in that. The feedback control torque calculating means includes
The engine control apparatus according to claim 8 , wherein the integral control torque value is changed according to an engine load during idle operation. The feedback control torque calculating means includes
The engine according to claim 8 or 9 , wherein when the learning condition set in advance is satisfied, the integral control torque value is learned, and the feedback control torque is calculated using the learned integral control torque value. Control device.

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