JPH03213638A - How to control drive wheel torque - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A0 OBJECTS OF THE INVENTION (1) Field of Industrial Application The present invention relates to a method for controlling drive wheel torque used in a traction control system or the like for preventing excessive slip of drive wheels.

(2) Conventional technology In a so-called traction control system that prevents excessive slip of the drive wheels when starting or accelerating a vehicle, there is a method of controlling the output torque of the internal combustion engine as a means of reducing the drive wheel torque, and a method of controlling the drive wheels. Methods of controlling power are known.

As means for controlling the output torque of the internal combustion engine, a method of controlling the ignition timing of the internal combustion engine and a method of controlling the throttle opening are generally used.

Japanese Patent Laid-Open No. 61-4325 discloses a control device for an internal combustion engine that combines the ignition timing and throttle opening control of the internal combustion engine.
The one described in Publication No. 1 is known. This device detects a value that correlates to the output torque of the internal combustion engine, and uses the detected value as a feedback signal to correct the throttle opening in order to match this detected value with the target output value determined from the opening of the accelerator pedal. At the same time, the detected value is used as a feedback signal to control the ignition timing to a value that provides the maximum output, thereby eliminating the influence of the external environment and changes over time on the output torque of the internal combustion engine.

(3) Problems to be Solved by the Invention Incidentally, the output torque of an internal combustion engine varies depending on air/fuel consumption, etc. in addition to the throttle opening and ignition timing, and furthermore, the driving wheel torque varies in addition to the above-mentioned output torque of the internal combustion engine. It also changes depending on transmission efficiency, gear ratio, brake oil pressure, etc. Therefore, when it is desired to control the drive wheel torque to a predetermined value in a certain driving state by using the above multiple parameters (for example, throttle opening and ignition timing) in combination, the overall drive wheel torque corresponding to the amount of change in each parameter There is a problem in that precise control cannot be performed unless the amount of change is accurately understood.

The present invention has been made in view of the above-mentioned circumstances, and it converts the influence of a change in one parameter on the drive wheel torque out of the two parameters that affect the drive wheel torque into the amount of change in the other parameter. By doing so, the purpose is to enable more precise control of driving wheel torque.

B9 Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a first parameter and a A driving wheel torque control method that changes a second parameter, wherein an amount of change in the driving wheel torque corresponding to an amount of change in the first parameter is calculated, and the second parameter corresponds to the amount of change in the driving wheel torque. This method is characterized by calculating the amount of change in the second parameter.

At this time, the first parameter can be the ignition timing of the internal combustion engine that drives the drive wheels, and the second parameter can be the throttle opening of the internal combustion engine.

(2) Effect According to the above configuration, first, the amount of change in drive wheel torque caused by a change in the first parameter (for example, ignition timing) is calculated, and then the same change in drive wheel torque is generated. The second parameter required for (e.g.
(throttle opening) is determined. This makes it possible to mutually convert the two parameters that affect the drive wheel torque, making it possible to easily and accurately control the drive wheel torque.

(3) Example Hereinafter, an example in which the present invention is applied to a traction control system for a vehicle will be described based on the drawings.

FIG. 2 is a schematic configuration diagram of a vehicle in which the present control method is implemented, and this vehicle is equipped with a pair of drive wheels Wr and a pair of driven wheels Wf driven by an internal combustion engine E.
r and the driven wheel Wf are respectively provided with a driving wheel speed detector 1 and a driven wheel speed detector 2 for detecting their speeds V, , V,. The internal combustion engine E is provided with a rotation speed detector 3 consisting of a gear and an electromagnetic pink-up for detecting the rotation speed Ne of its crankshaft, and an intake pipe internal pressure P in the intake passage 4.

A throttle valve 7 connected to an intake pipe internal pressure detector 5 and a pulse motor 6 to be driven to open and close is provided, and a spark plug 8 of the internal combustion engine E is provided with an ignition retard mechanism to adjust the ignition timing. 9 is connected. Further, an atmospheric pressure detector 10 for detecting atmospheric pressure PA is provided near the internal combustion engine E. The driving wheel speed detector 1, the driven wheel speed detector 2, and the rotational speed detector 3
, an intake pipe internal pressure detector 5, a pulse motor 6, an ignition retard mechanism 9, and an atmospheric pressure detector 10 are connected to an electronic control unit U consisting of a microcomputer.

FIG. 3 shows that the detection signals inputted from the respective detectors are processed based on a control program, and the throttle valve 7 is driven via the pulse motor 6 in order to suppress excessive slip of the drive wheel W. An electronic control unit U for adjusting the ignition timing of the spark plug 8 via the ignition retard mechanism 9 to reduce the output torque of the internal combustion engine E is shown.

This electronic control unit l-U includes a central processing unit (CPU) 11 for performing the arithmetic processing, a read-only memory (ROM) 12 that stores data such as the control program and various maps, and a detection system for each of the detectors. Random access memory (RAM) 1 that temporarily stores signals and calculation results
3, an input section 14 to which each of the above-mentioned detectors, that is, the driving wheel speed detector 1, the driven wheel speed detector 2, the rotational speed detector 3, the intake pipe internal pressure detector 5, and the atmospheric pressure detector 10, is connected; It consists of an output section 15 to which a pulse motor 6 and an ignition retard mechanism 9 are connected. The electronic control unit U uses the central processing unit 11 to perform arithmetic processing on each detection signal input from the input section 14 and data stored in the read-only memory 12 based on a control program to be described later. The pulse motor 6 and the ignition retard mechanism 9 are driven via the output section 15. This results in
The opening degree of the throttle valve 7 and the ignition timing of the spark plug 8 are controlled to change the output torque of the internal combustion engine E, and as a result, the drive wheel torque is controlled to an optimal value in order to suppress excessive slip of the drive wheels Wr of the vehicle. be done.

Next, the contents of the drive wheel torque control program executed in the electronic control unit U will be explained.

The difference between the driving wheel speed ■8 outputted by the driving wheel speed detector 1 and the driven wheel speed ■9 outputted by the driven wheel speed detector 2 exceeds a predetermined value and the driving wheel Wr is causing excessive slip. When detected, the output torque of the internal combustion engine E is reduced to reduce the driving wheel torque to a predetermined value in order to suppress this excessive slip.

The control to reduce the output torque of the internal combustion engine E is performed by controlling the ignition timing via the ignition retard mechanism 9 and controlling the throttle valve 7 via the pulse motor 6 in combination. At that time, the output torque of the internal combustion engine E changes depending on both the first parameter, ignition timing, and the second parameter, the throttle opening.
It is necessary to know in detail the influence that changes in both parameters have on the output of the internal combustion engine E. To do this, for example, it is necessary to mutually convert the ignition retard amount for reducing the output torque of the internal combustion engine E by a predetermined value and the amount of change in throttle opening required to cause the same output reduction.

Hereinafter, based on the flowchart of FIG. 1, the first parameter, the ignition timing retard amount IGRLVL, will be
The amount of change θaHrG in the throttle opening is a parameter of
The method for converting to Il will be explained in detail.

First, in step S1, the ignition retard amount IGRL
The ignition retard correction coefficient KIGiIl, which gives the output torque reduction rate of the internal combustion engine E corresponding to VL, is retrieved from the data stored in the read-only memory 12. In this ignition retard correction coefficient, GTD is, for example, the ignition retard amount I
When GRLVL is 10°, 20@, and 30°, they are given as 0.1, 0.2, and 0.3, respectively.

Next, in step S2, the ignition retard correction coefficient is set to the internal combustion engine output torque TQOUT before retard.
Multiplying T is the total amount of torque change due to ignition retard, T.
Q+c* is calculated. At this time, the internal combustion engine output torque TQooy before retard is determined as a function of the rotational speed Ne of the internal combustion engine E outputted by the rotational speed detector 3 and the intake pipe internal pressure P outputted by the intake pipe internal pressure detector 5, for example. Calculated from the power performance curve of

Next, in step S3, the torque change amount TQI
Amount of change in throttle opening θTNI to produce □
Gm is calculated by multiplying the torque change amount TQIGII by dTH/dTQ, which indicates the throttle opening change necessary to give a unit torque change at the crankshaft, and the atmospheric pressure correction coefficient by 0. At this time, as shown in FIG. 4, the throttle opening change dTH/dTQ required to give a unit torque change is the rotational speed N of the internal combustion engine E.
e and is stored as a function of the rotational speed detector 3.
The search is performed based on the rotational speed Ne output by. Also,
KPA is an atmospheric pressure correction coefficient for correcting the above dTH/dTQ given by the standard atmospheric pressure, and is given as a function of the atmospheric pressure PA detected by the atmospheric pressure detector 10 as shown in FIG.

Since the ignition retard amount IGRLVL for giving a predetermined torque change amount TQIGR to the internal combustion engine E is converted to the throttle opening change amount θTHIG11, the internal combustion engine E is changed in order to suppress excessive slip of the drive wheels Wr. When controlling the output torque based on both the ignition timing and throttle opening parameters, the effects of both parameters on the output torque of the internal combustion engine E can be accurately grasped, making it possible to precisely and easily control the driving wheel torque. It becomes possible.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various small design changes can be made without departing from the scope of the invention described in the claims. Is possible.

For example, in the embodiment, ignition timing and throttle opening are used as the first and second parameters, but in addition to the above parameters, air fuel consumption and brake oil pressure are also used as parameters, and these are used in combination as appropriate. be able to. Furthermore, it is clear that the present method is not limited to traction control systems, but can also be applied to auto cruise systems and normal driving.

C0 Effects of the Invention As described above, according to the present invention, when changing the first and second parameters to control the driving wheel torque, the amount of change in the driving wheel torque caused by the change in the first parameter is controlled. Since the amount of change in the second parameter that corresponds to generating this amount of change is calculated, it is possible to mutually convert the two parameters that affect the drive wheel torque, and as a result, the amount of change in the second parameter that is equivalent to generating this amount of change is calculated. Wheel torque can be controlled easily and precisely.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the contents of a control program executed in the electronic control unit, FIG. 2 is a schematic configuration diagram of a vehicle equipped with a control device that implements this method, and FIG.
The figure is a block diagram showing the electronic control unit, and Figure 4 is a block diagram showing the electronic control unit.
A graph showing the relationship between and dTH/dTQ, and FIG. 5 is a graph showing the relationship between P and 7. E...Internal combustion engine, Wr...Drive wheel, TQrc*...Amount of change in drive wheel torque, IGRLVL-...Ignition retard amount\θTHIGH...Amount of change in throttle opening

Claims (1)

[Scope of Claims] [1] A drive wheel torque control method that changes a first parameter and a second parameter to control the drive wheel torque, the method comprising: changing the amount of change in the first parameter (IGRLVL); The amount of change in the corresponding drive wheel torque (TQ_I_G_R) is calculated, and the amount of change in the second parameter (θ_T_H_
1. A method for controlling driving wheel torque, the method comprising calculating the torque of a driving wheel. [2] The drive wheel torque control method according to claim [1], wherein the first parameter is ignition timing of an internal combustion engine (E) that drives the drive wheels (Wr). [3] Claim [1] wherein the second parameter is a throttle opening degree of an internal combustion engine (E) that drives the drive wheels (Wr).
] The method for controlling driving wheel torque described in [1].