JPS5827855A - Extreme value controlling method for optimal control apparatus for internal-combustion engine and circuit used therefor - Google Patents

Abstract

PURPOSE:To improve response of control, by changing the amount of fuel or intake air to be supplied to an engine according to the output of a particular integrating apparatus to which a signal relating to the engine speed is applied. CONSTITUTION:A signal 1 relating to the engine speed is filtered by a lowpass filter 3, and the deviation from the original signal is detected by a subtractor 4 and afforded to an integrator 5 having a reset function. A reset signal 8 from a micro processor 7, to which the output of the integrator 5 is furnished, is afforded to the integrator 5, and the output of the micro processor 7 is applied to an injector driving circuit 10 via a timer 9. In operation of the above apparatus, the amount of supplied fuel F is increased, for instance, at a time instant T1, and outputIof the integrator 5 is set atI0. After passing of a predetermined time, the outputIof the integrator 5 is read by the processor 7 at a time instant t2, and increment of fuel is calculated and set in the timer 9. At the same time, the output of the integrator 5 is set atI0 by resetting the integrator 5 again. Thus, it is enabled to control fuel supply correctly according to change in the engine speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention detects changes in engine operating quantities, such as engine speed and torque, by changing the amount of intake air or fuel in an internal combustion engine optimal control device, and detects whether the change is maximum or minimum. The present invention relates to an extreme value control method and circuit for controlling the extreme value to a certain value.

Conventionally, this type of device has been equipped with an auxiliary throttle valve driven by an A pulse motor in the bypass path of the intake pipe as a means of changing the amount of intake air, and a pin throttle valve controlled by the opening and closing of a solenoid valve. 2. Description of the Related Art Devices equipped with a torque detector as means for detecting characteristic quantities are known. The operation of this conventional device is to open and close the solenoid valve at regular intervals, and when the torque when the solenoid valve opens increases or the torque when the solenoid valve closes decreases, the sub-throttle valve is operated to reduce the amount of intake air. Drive to increase;
If the solenoid valve opening torque decreases or the solenoid valve closing torque increases, the above-mentioned subprint valve is driven so that the intake air amount decreases. This is to control the maximum torque point, that is, the minimum fuel efficiency point when the intake air amount is changed with the fuel amount constant, but in the extreme value control described above, the sub-throttle valve is operated. When controlling the intake air amount, the direction of increase or decrease can be detected, but since the controlled amount is constant, it usually takes time to converge, and on the other hand, if the controlled amount is increased, hunting occurs. Further, there is no known specific example of extreme value control in which the intake air amount is kept constant and the fuel amount is varied to maximize the torque or rotational speed at 9 o'clock, thereby maximizing the output.

Therefore, an object of the present invention is to change the amount of intake air or fuel when the operating characteristic amount of the engine changes by changing the amount of intake air or fuel, in contrast to the conventional extreme value control as described above. An extreme value control method for an internal combustion engine optimal control device, which can increase the accuracy by increasing the convergence property by changing the amount, and by controlling the detection of the amount of change by taking a time delay into consideration. There is a need to provide systems and circuits.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the extreme value control method and circuit for an internal combustion engine optimum control device (hereinafter simply referred to as the extreme value control method and circuit) of the present invention will be explained in more detail based on nine preferred embodiments shown in the accompanying drawings.

To make the present invention easier to understand, when the amount of intake air is constant,
An extremum value control method and circuit for controlling the rotation speed to a maximum by changing the amount of fuel will be explained.

FIG. 1 is a block diagram showing the configuration of the extreme value control circuit of the present invention, in which reference numeral 1 is a good signal related to the engine rotation speed, such as an ignition signal, 2 is a frequency-voltage converter, and 3 is a frequency-voltage converter. is a low-pass filter, 4 is a frequency-voltage converter 2
and a subtractor 5 for subtracting the output from the low-pass filter 3.
is an integrator with a reset function, 6 is an A/D converter, and 7 is an integrator with a reset function.
is the microprocessor, 8 is this microprocessor 7
9 is a timer for converting the output value of the microprocessor 7 into the output value t-/Cruz width, and lO is an injector drive circuit.

The operation of the extreme value control circuit of the embodiment shown in the block diagram in FIG. 1 will be explained with reference to the waveform diagram in FIG. 2. In FIG. 2, F is the fuel amount, N is the rotation speed, ■ is the output of integrator 5,
T indicates the time axis t, and the fuel is increased at time t4. At the same time, the integrator 5t is reset to the value tI@. After a while, the rotation starts to increase. Accordingly, the output of the low-pass filter 3 lags behind the output of the frequency-voltage converter 20, so the output of the subtracter 4 increases in the negative direction. As a result of this, the output of the integrator 5 increases as shown by the curve from time t1 to time t in FIG.

After a predetermined period of time has elapsed, the microprocessor 7 outputs I at time t.
Read the value of , calculate the fuel increment according to this value, and -
Set timer 9. This indicates an increase in F at time t in FIG. At the same time, a signal 8 is issued to reset the integrator 5 again, and the integral can output becomes . In this way, the integrator is reset at the same time as the fuel increases or decreases using extreme value control, and the next amount of fuel increase or decrease is adjusted according to the value of the integrator after a predetermined time has elapsed. control to maximize.

Note that, after the amount of change in the amount of fuel or the number of revolutions falls within a predetermined range, the amount of fuel may be fixed at the value at that time.

In the above explanation, we talked about a method of controlling the rotation speed to the maximum by changing the fuel amount while keeping the intake air amount constant, but by changing the intake air amount by changing the fuel amount - wax, the rotation speed and torque etc. may be controlled so that it is maximized,
The same effects as in the embodiment described above are achieved.

As explained above, according to the extreme value control method and circuit for an internal combustion engine optimal control device of the present invention, the control amount of extreme value control can be controlled according to the amount of change in the operating characteristic quantity, and paternal delay is also taken into consideration. Since it can be controlled by the user, it has great effects such as improved responsiveness and highly accurate extreme value control.

[Brief explanation of drawings]

FIG. 1 is a block diagram schematically showing the configuration of an extreme value control circuit for an internal combustion engine optimum control device according to the present invention, and FIG. 2 shows the rotation speed, etc., in order to explain the operation of the circuit shown in FIG. It is a waveform diagram showing the waveform of each part including 2... Frequency voltage converter, 3... Low-pass filter acoustic, 4...
...Subtractor, 5...Integrator, 6...A/D converter,
F...Microprocessor, 10...Injector drive circuit. In the drawings, the same reference numerals indicate the same or equivalent parts. Agent Shin Kuzuno −

Claims (1)

[Claims] (1) An extreme value control method for an internal combustion engine optimal control device, comprising:
Detecting the rotational speed of the internal combustion engine and filtering the signal tube in the low range, integrating the difference between the rotational speed signal and the signal after the low-frequency filtering, and outputting the output t'A/D of the device that performs the integration. /D converter and a microphone f whose input signal is the rotation speed signal.
The integrator t is activated by the extreme value control start signal from the four processors.
An extreme value control method for an internal combustion engine optimum control device, which comprises setting the amount of fuel or the amount of intake air in accordance with a change in the output of an integrator that occurs as the rotational speed increases or decreases. (2. In the extreme value control method for an internal combustion engine optimum control device according to claim 2, the timing for adjusting the fuel amount or intake air amount by the integral value output change is set for a predetermined time from the extreme value control start time. An extreme value control method for an internal combustion engine optimal control device, characterized in that: (3) means for detecting the rotation speed of the internal combustion engine; and means for filtering the rotation speed signal from the detection means in a low range; , means for integrating the difference between the rotational speed signal and the signal after low-pass filtering, means for setting an integrator tIJ as the integrating means, and an A/D converter for A/D converting the output of the integrator. An extreme value control circuit for an internal combustion engine optimum control device, comprising: the A/D converter; and a micro zero processor that uses the rotational speed signal as an input signal.