Electronic control method for throttle and electronic control throttle device

Abstract

An electronic control method for a throttle by an electronic control throttle device that controls the throttle while an electronic control unit generates a control signal based on an input data signal. The method may include calculating an engine rotation speed deviation from a difference between an engine rotation speed and an input engine rotation speed command, calculating an engine rotational acceleration based on the engine rotation speed, obtaining a proportional torque from a product of the engine rotation speed deviation and a predetermined coefficient, obtaining an integral torque by integrating a value obtained by subtracting a product of the engine rotational acceleration and the predetermined coefficient from the product of the engine rotation speed deviation and the predetermined coefficient, and generating a control signal for the throttle by using a sum of the proportional torque and the integral torque as a value of a torque command.

Claims

1. An electronic throttle control method by an electronic control throttle device that performs opening and closing control of the throttle while an electronic control unit generates a control signal based on an input data signal, the method, by the electronic control unit, comprising: calculating an engine rotation speed deviation from a difference between an engine rotation speed and an input engine rotation speed command; calculating an engine rotational acceleration based on the engine rotation speed; obtaining a proportional torque from a product of the engine rotation speed deviation and a predetermined coefficient; obtaining an integral torque by integrating a value obtained by subtracting a product of the engine rotational acceleration and the predetermined coefficient from the product of the engine rotation speed deviation and the predetermined coefficient; and generating the control signal for the throttle by using a sum of the proportional torque and the integral torque as a value of a torque command.

2. The electronic control method for the throttle according to claim 1, wherein the predetermined coefficient for obtaining the product with the engine rotational acceleration when obtaining the integral torque is a time constant when the engine rotation speed converges to the input engine rotation speed command.

3. An electronic control throttle device, comprising: a throttle to which an actuator is attached; and an electronic control unit configured for opening and closing control of the throttle via the actuator and generating a control signal based on an input data signal; wherein the electronic control unit includes: a rotation speed deviation calculation unit configured to calculate an engine rotation speed deviation from a difference between an engine rotation speed and an engine rotation speed command; a rotational acceleration calculation unit configured to calculate an engine rotational acceleration based on the engine rotation speed; a proportional torque calculation unit configured to obtain a proportional torque from a product of the engine rotation speed deviation and a predetermined coefficient; and an integral torque calculation unit configured to obtain an integral torque by integrating a value obtained by subtracting a product of the engine rotational acceleration and the predetermined coefficient from the product of the engine rotation speed deviation and the predetermined coefficient; and wherein the electronic control unit is configured to generate the control signal for the throttle by using a sum of the proportional torque and the integral torque as a value of a torque command.

4. The electronic control throttle device according to claim 3, wherein the predetermined coefficient for obtaining the product with the engine rotational acceleration when obtaining the integral torque is a time constant when the engine rotation speed converges to the engine rotation speed command.

5. A method of controlling a throttle of an electronic control throttle device, comprising operating an electronic control unit of the electronic control throttle device to generate a control signal based on an input data signal, wherein operating the electronic control unit includes: calculating an engine rotation speed deviation from a difference between an engine rotation speed and an input engine rotation speed command; calculating an engine rotational acceleration based on the engine rotation speed; obtaining a proportional torque from a product of the engine rotation speed deviation and a predetermined coefficient; obtaining an integral torque by integrating a value obtained by subtracting a product of the engine rotational acceleration and the predetermined coefficient from the product of the engine rotation speed deviation and the predetermined coefficient; and generating the control signal for the throttle by using a sum of the proportional torque and the integral torque as a value of a torque command.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a simplified configuration diagram of an electronic control throttle device according to a preferred embodiment of the present invention;

(2) FIG. 2 is a functional block diagram illustrating control contents by an electronic control throttle device according to the embodiment illustrated in FIG. 1;

(3) FIG. 3 is a graph illustrating a transition of an engine rotation speed and an integral torque in a control example by the electronic control throttle device according to the embodiment illustrated in FIG. 1;

(4) FIG. 4 is a simplified configuration diagram of an electronic control throttle device according to a conventional example;

(5) FIG. 5 is a functional block diagram showing control contents by the electronic control throttle device of FIG. 4; and

(6) FIG. 6 is a graph illustrating a transition of an engine rotation speed and an integral torque in a control example by the electronic control throttle device of FIG. 4.

DETAILED DESCRIPTION

(7) Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(8) FIG. 1 schematically illustrates a functional configuration of an electronic control throttle device 1A as a preferred embodiment for executing an electronic control method for a throttle according to the present invention.

(9) The electronic control throttle device 1A includes a throttle 2 to which an actuator (not illustrated) is attached, and an electronic control unit 10A that performs opening and closing control of the throttle 2. The electronic control unit 10A automatically performs opening and closing control of the throttle 2 while generating a control signal by a predetermined calculation method based on various data signals input thereto.

(10) In addition, the electronic control unit 10A includes, as unit functionally configured by software stored in a storage unit (not illustrated), a rotation speed calculation unit 10a that calculates an engine rotation speed, a rotation speed deviation calculation unit 10b that calculates an engine rotation speed deviation, a rotational acceleration calculation unit 10d that calculates an engine rotational acceleration, a proportional torque calculation unit 10c that obtains a proportional torque, and an integral torque calculation unit 10e that obtains an integral torque. Note that, in a case where the data signal of the engine rotation speed, not the pulse signal, is input to the electronic control unit 10A, the above-described rotation speed calculation unit 10a is unnecessary.

(11) Next, control contents executed by the electronic control unit 10A will be described in detail with reference to the configuration diagram of FIG. 1 and the functional block diagram of FIG. 2.

(12) First, the rotation speed calculation unit 10a calculates the engine rotation speed from a cycle of a pulse signal input from a crank pulse sensor (not illustrated), the rotation speed deviation calculation unit 10b calculates the engine rotation speed deviation from a difference between the engine rotation speed and an issued engine rotation speed command (target rotation speed), and the rotational acceleration calculation unit 10d calculates the engine rotational acceleration based on the engine rotation speed.

(13) Then, the proportional torque calculation unit 10c calculates a product of the engine rotation speed deviation and a predetermined coefficient to obtain a proportional torque, and the integral torque calculation unit 10e performs calculation of integrating a value obtained by subtracting the product of the engine rotational acceleration and the predetermined coefficient from the product of the engine rotation speed deviation and the predetermined coefficient to obtain an integral torque, and generate a control signal for the throttle 2 using a sum of the proportional torque and the integral torque as a value of a torque command.

(14) In this case, the calculation performed by the integral torque calculation unit 10e is based on the following expression 1.
Torq.sub.i=K.sub.i∫{(ω.sub.ref−ω)−τω′}dt  [Formula 1]

(15) In the expression 1, Torq.sub.1 is an integral torque, K.sub.i is an integral torque gain, ω.sub.ref is an engine rotation speed command, ω is an engine rotation speed, τ is an arbitrarily settable coefficient, and ω′ is an engine rotational acceleration. However, in the present embodiment, a term −τω′ is added to the integral term performed by the conventional integral torque calculation unit 10f in FIG. 4, and the engine rotational acceleration is used for the calculation for obtaining the integral torque.

(16) Hereinafter, the operation of the electronic control throttle device 1A of the present embodiment will be described with reference to the graph of FIG. 3.

(17) This graph illustrates a change in the integral torque when converging to the engine rotation speed command while applying a load when the actual engine rotation speed is higher than the engine rotation speed command in the electronic control throttle device 1A described above. The integral torque in the present embodiment operates so as to accelerate when (ω.sub.ref−ω)−τω′ in the expression 1 is positive and decelerate when (ω.sub.ref−ω)−τω′ in the expression 1 is negative. Therefore, the engine rotation speed in this case operates so as to follow (ω.sub.ref−ω)−τω′=0, that is, the following expression 2.

(18) $\left[\mathrm{Formula}2\right]$$\begin{array}{cc}\frac{d}{dt}\omega =\frac{1}{\tau }\left({\omega }_{ref}-\omega \right)& \left(2\right)\end{array}$

(19) From the expression 2, τ set here is a time constant when the engine rotation speed converges to the engine rotation speed command. Therefore, even when the engine rotation speed is higher than the engine rotation speed command as in the integral torque in the conventional control illustrated in FIG. 6, the integral torque is not excessively reduced, so that undershoot of the engine rotation speed is less likely to occur, and occurrence of engine stall can be prevented.

(20) As described above, according to the present invention, in the electronic control of the throttle, it is possible to make the decrease in the rotation speed of the engine and the engine stall less likely to occur when a load is applied.