JP2011256721A - Throttle valve control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve convergence of the position of a throttle valve (hereinafter referred to as a throttle) without performing complicated processing.SOLUTION: In a device for controlling the throttle by a DC motor, impressed voltage V to be supplied to the motor is determined by processing for every fixed time Ts. In the processing, non-load speed No of the motor corresponding to voltage (V-Vs) deducted with spring force compensation voltage Vs (voltage to make the motor output the same force as that of a return spring of the throttle) from the determined impressed voltage V is calculated (S120). A prediction position Pe of the throttle is calculated from the No (S130). Fixed speed of the motor to operate the throttle by a difference between a target position Pt and the prediction position Pe for the fixed time Ts is calculated as requested speed Nr (S150). Smaller voltage of voltage Vr that the Vs is added to the impressed voltage (=Ke*Nr) of the motor corresponding to the non-load speed of the same value as the Nr and battery voltage Vb is made as the impressed voltage V (S160, S170).

Description

  The present invention relates to a throttle valve control device that controls a throttle valve by driving a DC (direct current) motor as an actuator that operates a throttle valve of an internal combustion engine.

  As this type of throttle valve control device, for example, as described in Patent Document 1, the actual opening (actual position) of the throttle valve is detected, and the detected actual opening and the depression amount of the accelerator pedal, etc. In some cases, the DC motor is subjected to PID control so that the deviation becomes zero according to the deviation from the command value (that is, the target opening) of the opening set based on the above. And in patent document 1, the convergence property of the position of a throttle valve is improved by switching the various control gains of PID control according to a condition.

JP 10-47135 A

  In the above conventional technique, the control gain is switched according to the situation, so that the control process is complicated. Further, at the time of developing the device, an operation for verifying that the control gain in each of a plurality of situations is appropriate is performed, but this operation takes a lot of time.

  Therefore, an object of the present invention is to provide a throttle valve control device that can improve the convergence of the position of the throttle valve without performing complicated processing such as switching the control gain.

  A throttle valve control device according to claim 1 controls a throttle valve by driving a DC motor that operates a throttle valve of an internal combustion engine, and a target position determining means for determining a target position of the throttle valve; It operates at fixed time intervals, determines a drive application voltage to be applied to the DC motor in order to bring the throttle valve position to the determined target position, and supplies the determined drive application voltage to the DC motor. Drive control means.

Then, the drive control means determines the applied voltage for driving using the theory that the integral value of the no-load rotational speed of the DC motor is equal to the actual rotational amount of the DC motor.
Here, the theory will be described.

  First, a torque T of a DC motor (hereinafter also simply referred to as a motor) is obtained by Equation 1.

尚、「Ｋｔ」はモータのトルク定数、「Ｒ」はモータのコイルの抵抗、「Ｖ」はモータの印加電圧、「Ｖｅ」はモータの逆起電力である。

“Kt” is a motor torque constant, “R” is a resistance of a motor coil, “V” is a voltage applied to the motor, and “Ve” is a counter electromotive force of the motor.

  Further, if the back electromotive force constant of the motor is “Ke”, the no-load rotational speed of the motor (the rotational speed at which T = 0) is “No”, and the rotational speed of the motor is “N”, the following formula 2 And the relationship of Equation 3.

V = Ke · No Equation 2
Ve = Ke · N Equation 3
From Equation 2 and Equation 3, Equation 1 becomes Equation 4.

従って、モータのイナーシャモーメントを「Ｉ」とすると、モータの角加速度（ｄＮ／ｄｔ）は、式５となる。

Therefore, when the inertia moment of the motor is “I”, the angular acceleration (dN / dt) of the motor is expressed by Equation 5.

そして、式５において、モータの緒元（特性値）によって決まる定数部分を、式６の如く「Ｋ」に置き換えると、モータの回転数Ｎは、式７で表される。

When the constant portion determined by the motor specification (characteristic value) in Expression 5 is replaced with “K” as shown in Expression 6, the rotational speed N of the motor is expressed by Expression 7.

  K = (Kt · Ke) / (R · I) Equation 6

式７における括弧内の第２項は、モータの回転量なので、目標位置までの回転量をＸとし、目標位置での回転数を０とすると、式７は、式８となり、その式８から式９が得られる。

Since the second term in parentheses in Equation 7 is the amount of rotation of the motor, if the amount of rotation to the target position is X and the number of rotations at the target position is 0, Equation 7 becomes Equation 8, and from Equation 8 Equation 9 is obtained.

そして、その式９から、図１に示すように、モータの無負荷回転数の積分値がモータの実回転量（実際の回転量）と等しくなることが分かる。

From Equation 9, it can be seen that the integrated value of the no-load rotation speed of the motor is equal to the actual rotation amount (actual rotation amount) of the motor, as shown in FIG.

  In FIG. 1, an applied voltage Vo corresponding to a certain no-load rotational speed No is supplied to the motor for a time to. In this case, the supply of the voltage Vo ends from the start of the supply of the voltage Vo, and the inertial rotation of the motor. The actual rotation amount of the motor until is finished is the same as the product of the no-load rotation speed No and the time to (= No × to). For this reason, the applied voltage Vo corresponding to the no-load rotational speed No obtained by dividing the motor rotation amount required to operate the throttle valve to the target position by the time to is obtained from Equation 2, and the applied voltage Vo is calculated. If the time to is supplied to the motor, the throttle valve reaches the target position and converges when the supply of the applied voltage Vo to the motor ends and the inertial rotation of the motor ends.

  In other words, if the voltage is supplied to the motor so that the rotation amount of the motor required to operate the throttle valve to the target position and the integral value of the no-load rotation speed No of the motor are the same, the voltage to the motor When the supply is finished and the inertial rotation of the motor is finished, the throttle valve converges to the target position. In addition, if the no-load rotation speed corresponding to the applied voltage supplied to the motor is integrated, the rotation amount of the motor can be obtained. Therefore, the operation of the throttle valve is determined from the no-load rotation speed corresponding to the applied voltage supplied to the motor. The position can be predicted.

  The present invention pays attention to these, and therefore, the drive control means is a means for determining the drive applied voltage to be supplied to the DC motor. Voltage calculating means. In the following description, the operation cycle of the drive control means (the predetermined time) is Ts.

  First, the prediction means calculates the no-load rotation speed of the DC motor corresponding to the drive application voltage from the drive application voltage determined last time (that is, the voltage supplied to the motor from a certain time Ts before to the present). A predicted position that is a predicted value of the position of the throttle valve is calculated from the calculated no-load rotation speed.

  The no-load rotation speed corresponding to the drive application voltage is the rotation speed (no-load rotation speed) of the DC motor when the drive application voltage is supplied to the DC motor in the no-load state. In addition, since the relationship between the applied voltage of the DC motor and the no-load rotation speed generally has the relationship of Equation 2, the other can be calculated from one.

  Then, the required rotational speed calculation means operates the throttle valve toward the target position by the difference for a certain time Ts according to the difference between the target position and the predicted position calculated by the prediction means. A certain rotation speed is calculated as the required rotation speed. In other words, when the rotational speed of the DC motor becomes constant for a certain time Ts, the required rotational speed calculation means operates the throttle valve toward the target position by the difference, and the constant rotational speed. The number is calculated as the required rotation speed. Furthermore, in other words, the required rotational speed calculation means uses, as the required rotational speed, a constant rotational speed of the motor that can obtain the rotational speed of the motor necessary for operating the throttle valve from the predicted position to the target position in a predetermined time Ts. calculate.

  Next, the required voltage calculation means requests the applied voltage of the DC motor corresponding to the required no-load rotation speed, which is the no-load rotation speed of the DC motor, with the same value as the required rotation speed calculated by the required rotation speed calculation means. Calculated as voltage. The applied voltage corresponding to the required no-load rotational speed is an applied voltage at which the rotational speed of the DC motor becomes the required no-load rotational speed when supplied to an unloaded DC motor.

The drive control means determines the required voltage calculated by the required voltage calculation means as the drive application voltage.
Such a drive control means calculates the predicted position of the throttle valve from the no-load rotational speed corresponding to the applied voltage (driving applied voltage) supplied to the motor from a certain time Ts before, and calculates the target position from the predicted position. The applied voltage for driving the motor so that the rotation amount of the DC motor required to operate the throttle valve to the position and the integral value of the no-load rotational speed corresponding to the applied voltage to the motor are the same. Will be determined.

  Therefore, according to the throttle valve control device of claim 1, when the target position and the predicted position of the throttle valve coincide with each other, the voltage supply to the DC motor for operating the throttle valve is stopped, and the DC motor rotates by inertia. When the inertial rotation of the DC motor is completed, the throttle valve position reaches the target position and converges.

  For this reason, the convergence of the position of the throttle valve can be improved without performing a complicated process of switching the control gain as in the prior art. In particular, in the P control (proportional control) in the normal feedback control, the DC motor is continuously driven as long as there is a difference between the target position and the actual position, so the convergence to the target position is poor. According to the valve control device, such poor convergence can be improved.

  Further, according to the throttle valve control device of claim 1, at the time of development, it is not necessary to perform work such as verifying that the control gain in each of a plurality of situations is appropriate as in the conventional device. Development work is also easier.

  Next, in the throttle valve control device according to a second aspect, in the throttle valve control device according to the first aspect, the drive control means has the required voltage calculated by the required voltage calculation means exceeding the maximum voltage that can be supplied to the DC motor. If so, the maximum voltage is determined as the drive application voltage, and if the request voltage calculated by the request voltage calculation means is equal to or less than the maximum voltage, the request voltage is determined as the drive application voltage.

  According to this configuration, it is possible to control the throttle valve to the target position while determining the drive applied voltage to the DC motor within the range of the maximum voltage that can be supplied to the DC motor.

  Even if the calculated required voltage exceeds the maximum voltage and the applied voltage for driving is set to a value (maximum voltage) smaller than the required voltage, the required voltage (extended (Applied voltage for driving) is increased, and eventually, the amount of motor rotation required to operate the throttle valve from the predicted position to the target position by operating the drive control means a plurality of times, and The applied voltage to the motor is adjusted so that the integrated value of the no-load rotational speed corresponding to the applied voltage to the motor is the same.

  A throttle valve control device according to a third aspect of the present invention is the throttle valve control device according to the first or second aspect, further comprising position detecting means for detecting an actual position which is an actual position of the throttle valve. The predicting means determines whether or not the throttle valve has stopped based on the change in the actual position detected by the position detecting means. If it is determined that the throttle valve has stopped, the predicting means detects by the position detecting means. The determined actual position is set as a predicted position.

  According to this configuration, when the target position of the throttle valve coincides with the predicted position, the DC motor enters the inertial rotation state, and when the inertial rotation of the DC motor is finished (that is, when the throttle valve stops), The actual position of the throttle valve is set as the predicted position.

  Therefore, if there is a difference between the actual position and the target position when the throttle valve is stopped, a difference will occur again between the target position and the predicted position, and the throttle valve will be set to the target position according to the difference. An applied voltage for driving is supplied to the DC motor. For this reason, the control accuracy of the throttle valve can be increased.

  Next, a throttle valve control device according to a fourth aspect of the present invention is the throttle valve control device according to any one of the first to third aspects, wherein the throttle valve is provided with an urging force for returning the throttle valve to the reference position. Force means are provided.

  The drive control means further includes a compensation voltage calculation means, and the compensation voltage calculation means has a force having the same magnitude as that of the urging force and in a direction opposite to the urging force, and the DC motor applies to the throttle valve. An urging force compensation voltage, which is an applied voltage to the DC motor, is calculated.

  Further, the predicting means uses the corrected applied voltage, which is a voltage obtained by subtracting the biasing force compensation voltage calculated by the biasing force compensation voltage calculating means from the previously determined driving application voltage, and corresponds to the corrected applied voltage. The no-load rotation speed of the DC motor is calculated, and the predicted position is calculated from the calculated no-load rotation speed. This is because the urging force compensation voltage portion of the driving applied voltage to the DC motor is used to generate a force that opposes the urging force by the urging means. For the same reason, the required voltage calculation means obtains a voltage obtained by adding the urging force compensation voltage calculated by the urging force compensation voltage calculation means to the applied voltage of the DC motor corresponding to the required no-load rotation speed. Calculate as

  According to this configuration, the throttle valve can be controlled to the target position in consideration of the influence of the urging force by the urging means. Therefore, even if there is an urging means, it is possible to ensure good control accuracy of the throttle valve.

By the way, in the throttle valve control device of claim 4, if the urging force of the urging means changes in accordance with the position of the throttle valve, it may be configured as in claim 5.
That is, in the throttle valve control device according to claim 5, in the throttle valve control device according to claim 4, the urging means changes its urging force in accordance with the position of the throttle valve. The throttle valve control device includes position detecting means for detecting an actual position that is an actual position of the throttle valve. Further, the urging force compensation voltage calculation means calculates the urging force compensation voltage based on the actual position detected by the position detection means.

  According to this configuration, even if the urging force of the urging means changes according to the position of the throttle valve, the throttle valve can be controlled to the target position in consideration of the influence of the changing urging force. Control accuracy can be ensured.

It is explanatory drawing of the principle which this invention utilizes. It is a block diagram showing ECU as a throttle valve control device of an embodiment with its peripheral equipment. It is a flowchart showing a drive control process. It is a 1st explanatory view explaining an operation of an embodiment. It is the 2nd explanatory view explaining an operation of an embodiment.

  Hereinafter, a throttle valve control device according to an embodiment to which the present invention is applied will be described. The throttle valve control device according to the present embodiment is an electronic control device that controls the throttle valve of the internal combustion engine. Hereinafter, the electronic control device is referred to as an ECU.

  As shown in FIG. 2, a throttle valve 3 that controls the amount of air taken into the engine 1 through the intake passage 2 is provided in the intake passage 2 of the engine 1 that is an internal combustion engine. A position sensor 4 for detecting the actual position of the throttle valve 3 (opening / closing position and opening degree) is provided.

  The accelerator pedal 5 of a vehicle (automobile) on which the engine 1 is mounted is provided with an accelerator opening sensor 6 that detects the amount of depression of the accelerator pedal 5 (hereinafter also referred to as accelerator opening). Signals from the position sensor 4 and the accelerator opening sensor 6 are input to an ECU 11 that is configured around a microcomputer (microcomputer) 10.

  Further, a reduction gear 13 is attached to the rotation shaft of the throttle valve 3, and the reduction gear 13 meshes with a pinion gear 15 attached to the rotation shaft of the DC motor 14. The throttle valve 3 is opened and closed by the rotation of the DC motor 14. That is, the DC motor 14 is used as the actuator of the throttle valve 3. The DC motor 14 is supplied with electric power from the ECU 11.

The gear ratio between the reduction gear 13 and the pinion gear 15 (the number of teeth of the reduction gear 13 / the number of teeth of the pinion gear 15) Kg is larger than 1, and is 10 in the present embodiment, for example.
In addition, a return spring (which is a so-called return spring, hereinafter simply referred to as a spring) 16 is provided on the rotation shaft of the throttle valve 3, and the throttle valve 3 is always at a predetermined reference position by the spring 16. Is biased in the direction. The reference position may be, for example, a fully closed position where the throttle valve 3 is fully closed, but in the present embodiment, the position of the throttle valve 3 where the engine 1 rotational speed is the idle rotational speed, or more Also, the throttle valve 3 is set at a position where it is slightly opened. This is because the operation of the engine 1 can be continued even if the control of the throttle valve 3 becomes impossible.

Next, processing executed by the microcomputer 10 of the ECU 11 to control the throttle valve 3 will be described.
First, the microcomputer 10 detects an accelerator opening based on a signal from the accelerator opening sensor 6 by a target position determination process that is periodically executed, and determines a target position of the throttle valve 3 from the accelerator opening. Therefore, it can be said that the microcomputer 10 functions as the target position determination unit 10a that determines the target position of the throttle valve 3 by executing the target position determination process. In the target position determination process, for example, to realize traction control for suppressing the output of the engine 1 when acceleration slip occurs on the driving wheels of the vehicle, vehicle posture control for stabilizing the vehicle running posture, and the like. In addition, the target position of the throttle valve 3 may be determined in accordance with various vehicle information other than the accelerator opening (such as the slip ratio of the drive wheels and the yaw rate of the vehicle).

  Further, the microcomputer 10 determines the drive application voltage to be applied to the DC motor 14 in order to set the position of the throttle valve 3 to the target position by executing the drive control process of FIG. Then, the determined applied voltage for driving is supplied to the DC motor 14.

  As shown in FIG. 3, when the microcomputer 10 starts the drive control process, first, in S103, the actual position (actual position) P of the throttle valve 3 is detected based on the signal from the position sensor 4.

Next, in S105, a spring force compensation voltage (corresponding to an urging force compensation voltage) Vs is calculated based on the actual position P detected in S103.
This spring force compensation voltage Vs has the same magnitude as the urging force of the spring 16 (specifically, the urging force that the spring 16 applies to the throttle valve 3) and a force in the direction opposite to the urging force. This is a voltage applied to the DC motor 14 that is necessary to be supplied to the valve 3.

  In this embodiment, the urging force of the spring 16 changes in accordance with the actual position P of the throttle valve 3. Therefore, in S105, a function indicating the correspondence between the position of the throttle valve 3 and the spring force compensation voltage Vs. By applying the actual position P detected in S103 to the (or data table) F, the spring force compensation voltage Vs corresponding to the actual position P is calculated. The function (or data table) F is determined by theoretical calculation and experiment, and is stored in the ROM of the microcomputer 10.

Next, in S110, it is determined whether or not the throttle valve 3 has been stopped based on the change in the actual position P detected in S103.
Specifically, for example, if the absolute value of the difference between the actual position P detected last time and the actual position P detected this time is smaller than a specified value (that is, if the operating speed of the throttle valve 3 is smaller than a predetermined value). ), It is determined that the throttle valve 3 has stopped. Further, for example, if the positive / negative polarity of the difference between the actual position P detected last time and the actual position P detected this time is reversed, the throttle valve 3 may be determined to have stopped.

  If it is determined in S110 that the throttle valve 3 is not stopped, the process proceeds to S120, and the applied voltage V for driving to the DC motor 14 previously determined in the drive control process and the spring calculated in S105 above. From the force compensation voltage Vs and the back electromotive force constant Ke of the DC motor 14, the no-load rotational speed No of the DC motor 14 is calculated by the following equation 10.

つまり、一定時間Ｔｓ前に決定した駆動用印加電圧Ｖからバネ力補償電圧Ｖｓを減じた電圧（Ｖ−Ｖｓ）である補正印加電圧を、式２に、印加電圧Ｖとして代入することで、その補正印加電圧に対応したＤＣモータ１４の無負荷回転数Ｎｏを算出している。

That is, by substituting a corrected application voltage, which is a voltage (V−Vs) obtained by subtracting the spring force compensation voltage Vs from the drive application voltage V determined before a certain time Ts, into the expression 2 as the application voltage V, The no-load rotational speed No of the DC motor 14 corresponding to the corrected applied voltage is calculated.

  In the next S130, the position of the throttle valve 3 is predicted from the no-load rotational speed No calculated in S120. Specifically, a predicted position Pe that is a predicted value of the position of the throttle valve 3 is calculated by the following equation 11.

尚、式１１の右辺における１項目（Ｐｅ）は、前回の予測位置Ｐｅである。また、式１１の右辺における２項目（Ｎｏ×Ｔｓ／Ｋｇ）は、前回処理時から今回処理時までの一定時間Ｔｓにおける無負荷回転数Ｎｏの積分値をギア比Ｋｇで割ったものであり、更に詳しい意味としては、前回処理時から今回処理時までの一定時間Ｔｓにおいて、ＤＣモータ１４が無負荷回転数Ｎｏで回転したと仮定した場合のスロットルバルブ３の移動量であり、図１に示した理論から、前回処理時に決定した駆動用印加電圧ＶをＤＣモータ１４に一定時間Ｔｓ供給したことによるスロットルバルブ３の移動量である。このため、その移動量を前回の予測位置Ｐｅに加えることで、今回の予測位置Ｐｅを算出している。このため、Ｓ１３０では、Ｓ１２０で算出される無負荷回転数Ｎｏを積分した値（即ち、ＤＣモータ１４の回転量）をギア比Ｋｇで割ることで、予測位置Ｐｅを算出していると言える。

Note that one item (Pe) on the right side of Equation 11 is the previous predicted position Pe. In addition, two items (No × Ts / Kg) on the right side of Expression 11 are obtained by dividing the integral value of the no-load rotational speed No during a certain time Ts from the previous processing to the current processing by the gear ratio Kg. More specifically, the amount of movement of the throttle valve 3 when it is assumed that the DC motor 14 has rotated at a no-load rotational speed No in a certain time Ts from the previous processing to the current processing is shown in FIG. From the above theory, this is the amount of movement of the throttle valve 3 when the drive application voltage V determined during the previous process is supplied to the DC motor 14 for a predetermined time Ts. Therefore, the current predicted position Pe is calculated by adding the movement amount to the previous predicted position Pe. For this reason, in S130, it can be said that the predicted position Pe is calculated by dividing the value obtained by integrating the no-load rotation speed No calculated in S120 (that is, the rotation amount of the DC motor 14) by the gear ratio Kg.

When the predicted position Pe is calculated in S130, the process proceeds to S150.
On the other hand, when it is determined in S110 that the throttle valve 3 has stopped, the process proceeds to S140, the actual position P detected in S103 is set as the predicted position Pe, and then the process proceeds to S150.

  In S150, the required speed of the DC motor 14 (corresponding to the required rotational speed) is calculated from the latest target position Pt calculated in the above-described target position determination process and the predicted position Pe calculated in S130 by the following equation 12. Nr is calculated.

この式１２では、目標位置Ｐｔと予測位置Ｐｅとの差分（Ｐｔ−Ｐｅ）を「ΔＰ」とすると、スロットルバルブ３を一定時間Ｔｓで当該差分ΔＰだけ目標位置Ｐｔへ向けて作動させることとなるＤＣモータ１４の一定の回転数を、要求速度Ｎｒとして算出している。

In Expression 12, when the difference (Pt−Pe) between the target position Pt and the predicted position Pe is “ΔP”, the throttle valve 3 is operated toward the target position Pt by the difference ΔP at a certain time Ts. A constant rotational speed of the DC motor 14 is calculated as the required speed Nr.

Next, in S160, the required voltage Vr to be applied to the DC motor 14 is calculated by the following equation (13).
Vr = Ke · Nr + Vs Equation 13
That is, the applied voltage (= Ke · Nr) of the DC motor corresponding to the required no-load rotation speed, which is the no-load rotation speed of the DC motor 14, having the same value as the required speed Nr calculated in S150 is calculated (formula 2), a voltage obtained by adding the spring force compensation voltage Vs calculated in S105 to the applied voltage (= Ke · Nr) is calculated as the required voltage Vr.

Then, in the next S170, the drive application voltage V to the DC motor 14 is determined from the required voltage Vr.
Specifically, in the present embodiment, the maximum voltage that the ECU 11 can supply to the DC motor 14 is the battery voltage (the voltage of the in-vehicle battery) Vb as the power supply voltage, and therefore, between the required voltage Vr and the battery voltage Vb. Thus, the smaller one is determined as the drive application voltage V. That is, if the required voltage Vr exceeds the battery voltage Vb, the battery voltage Vb is used as the drive application voltage V. If the request voltage Vr is equal to or less than the battery voltage Vb, the request voltage Vr is directly used as the drive application voltage V. To do.

In S170, the determined drive application voltage V is supplied to the DC motor 14, and then the drive control process is terminated.
Note that the variable drive application voltage V may be supplied as it is in the form of an analog voltage from the ECU 11 to the DC motor 14, but in this embodiment, it is supplied in the form of a PWM (Pulse Width Modulation) signal. . That is, the ECU 11 changes the duty ratio of the PWM signal that changes between 0 V and the battery voltage Vb according to the value of the drive application voltage V, thereby determining the applied voltage to be supplied to the DC motor 14. Control to the value of the applied voltage V. Specifically, if the determined drive application voltage V is M% of the battery voltage Vb (M is any of 0 to 100), the duty ratio of the PWM signal is set to M%. Thus, for example, if the applied voltage V for driving is equal to the battery voltage Vb, the duty ratio of the PWM signal is 100%, and if the applied voltage V for driving is half the battery voltage Vb, the duty ratio of the PWM signal is 50%. To.

Next, the operation of the drive control process of FIG. 3 will be described with reference to FIGS.
The target position determination process for determining the target position Pt of the throttle valve 3 and the drive control process (FIG. 3) in FIG. 3 may be executed asynchronously. In FIG. It is assumed that the determination process is executed immediately before the drive control process. In FIG. 4, each of the times t1 to t5 indicates five of the execution timings of the target position determination process and the drive control process every fixed time Ts. Further, in FIG. 4, [tn] (n is any one of 1 to 5) attached to each of Pt, Pe, Vr, and V is processing at which time tn that Pt, Pe, etc. It is shown whether it was calculated by.

  First, in FIG. 4, the throttle valve 3 is stopped before the time t1, and the target position Pt, the predicted position Pe, and the actual position P all coincide. Therefore, before time t1, the required speed Nr is calculated as 0 in S150 to S170 in FIG. 3, and the required voltage Vr becomes the spring force compensation voltage Vs (<battery voltage Vb). The drive applied voltage V becomes the spring force compensation voltage Vs. That is, the biasing force of the spring 16 and the force of the DC motor 14 are balanced, and the throttle valve 3 is in a stopped state. For this reason, in S120 of FIG. 3, the no-load rotation speed No is calculated as 0, and the predicted position Pe calculated in S130 of FIG. 3 does not change.

  Then, when the target position Pt becomes Pt [t1] at time t1, in the drive control process, the no-load rotational speed No is also calculated as 0 in S120, and the predicted position Pe [t1 calculated in S130. ] Does not change from the previous time, a difference occurs between the target position Pt and the predicted position Pe [t1]. Therefore, the required speed Nr corresponding to the difference between the target position Pt and the predicted position Pe [t1] is calculated (S150), and the required voltage Vr [t1] is calculated to a value larger than Vs (S160). . In this example, since the required voltage Vr [t1] exceeds the battery voltage Vb, the drive applied voltage V [t1] to the DC motor 14 becomes the battery voltage Vb (S170). In the example of FIG. 4, the target position Pt is the same from time t1 to time t5.

  Next, in the drive control process at time t2, in S120, the no-load rotation speed No is calculated from the drive applied voltage V [t1] output to the DC motor 14 from the previous time t1 to the present (t2). Therefore, the no-load rotational speed No is not 0, and the predicted position Pe [t2] calculated in S130 is updated from the previous predicted position Pe [t1].

  Even at this time, since there is a difference between the target position Pt and the predicted position Pe [t2], the required speed Nr corresponding to the difference is calculated (S150), and the required voltage Vr [t2] is larger than Vs. A value is calculated (S160). In this example, since the required voltage Vr [t2] also exceeds the battery voltage Vb, the drive application voltage V [t2] to the DC motor 14 becomes the battery voltage Vb (S170).

  Next, also in the drive control process at time t3, similarly to time t2, in S120, from the applied voltage V [t2] for driving output to the DC motor 14 from the previous time t2 to the present (t3), Since the no-load rotation speed No is calculated, the no-load rotation speed No is not 0, and the predicted position Pe [t3] calculated in S130 is updated from the previous predicted position Pe [t2].

  Even at this time, since there is a difference between the target position Pt and the predicted position Pe [t3], the required speed Nr corresponding to the difference is calculated (S150), and the required voltage Vr [t3] is larger than Vs. A value is calculated (S160). In this example, since the required voltage Vr [t3] is smaller than the battery voltage Vb, the driving applied voltage V [t3] to the DC motor 14 becomes the required voltage Vr [t3] (S170).

  Next, in the drive control process at time t4 as well as at times t2 and t3, the applied voltage V [t3] for driving output to the DC motor 14 from the previous time t3 to the present time (t4) at S120. Therefore, since the no-load rotation speed No is calculated, the no-load rotation speed No is not 0, and the predicted position Pe [t4] calculated in S130 is updated from the previous predicted position Pe [t3]. In the example of FIG. 4, at this time, the predicted position Pe [t4] matches the target position Pt.

  Then, in S150 to S170, the required speed Nr is calculated as 0, and the required voltage Vr [t4] becomes the spring force compensation voltage Vs. Therefore, the drive application voltage V [t4] to the DC motor 14 is the spring force. Compensation voltage Vs. Therefore, the DC motor 14 is supplied with a voltage corresponding to the biasing force of the spring 16.

  Therefore, if the target position Pt is not changed at the next time t5, the DC motor 14 stops after inertial rotation, and at that time, the position of the throttle valve 3 reaches the target position Pt. And converge.

  On the other hand, when the target position Pt is changed to Pt [t5] at time t5, similarly to time t1, in the drive control process, the no-load rotation speed No is calculated as 0 in S120, and is calculated in S130. Since the predicted position Pe [t5] to be performed is not different from the previous predicted position Pe [t4], a difference occurs between the target position Pt and the predicted position Pe [t5]. Therefore, the required speed Nr corresponding to the difference between the target position Pt and the predicted position Pe [t5] is calculated (S150), and the required voltage Vr [t5] is calculated to a value larger than Vs (S160). . In this example, since the required voltage Vr [t5] is smaller than the battery voltage Vb, the drive applied voltage V [t5] to the DC motor 14 becomes the required voltage Vr [t5] (S170).

The applied voltage V [t5] for driving is supplied to the DC motor 14 for a certain time Ts, so that the position of the throttle valve 3 converges to the target position Pt [t5].
If the change in the target position Pt is small at time t1 in FIG. 4 and the required voltage Vr [t1] calculated in S160 of the drive control process is smaller than the battery voltage Vb, the required voltage Vr [t1] Becomes the applied voltage V [t1] for driving, and at the next time t2, the predicted position Pe and the target position Pt coincide with each other, similarly to the time t4 in FIG. Therefore, the required speed Nr is calculated as 0, the required voltage Vr becomes the spring force compensation voltage Vs, and the drive application voltage V to the DC motor 14 returns from V [t1] to the spring force compensation voltage Vs. Then, the DC motor 14 stops after inertial rotation, and at that time, the position of the throttle valve 3 converges to the target position Pt. That is, the throttle valve 3 is moved to the target position by one drive control process. In FIG. 1, “Vo” is set to V [t1] (= Vr [t1]), and “to” is replaced with Ts. The operation will be as follows.

  On the other hand, as shown at time t6 in FIG. 5, when the inertial rotation of the DC motor 14 is finished and the throttle valve 3 is stopped, even if there is a deviation between the actual position P and the target position Pt, the drive control process is performed in S110. It is determined that the throttle valve 3 has stopped, and the actual position P is set as the predicted position Pe (S140).

  Therefore, as shown in FIG. 5, when there is a difference between the actual position P and the target position Pt when the throttle valve 3 is stopped, the difference between the target position Pt and the predicted position Pe (= P) again. Depending on the difference, the applied voltage V for driving the throttle valve 3 to the target position Pt is supplied to the DC motor 14 through S150 to S170 of the drive control process. Therefore, the control accuracy of the throttle valve 3 is increased.

  In the ECU 11 as described above, the voltage (V−Vs) obtained by subtracting the spring force compensation voltage Vs from the driving applied voltage V supplied to the DC motor 14 from the predetermined time Ts before the processing of S120 and S130 in FIG. Is calculated as a voltage (correction applied voltage) for operating the throttle valve 3, the no-load rotation speed No of the DC motor 14 corresponding to the voltage is calculated, and the predicted position of the throttle valve 3 is calculated from the no-load rotation speed No. Pe is calculated. Then, through the processing of S150 to S170 in FIG. 3, the rotation amount of the DC motor 14 required to operate the throttle valve 3 from the predicted position Pe to the target position Pt and the integral value of the no-load rotation speed No of the DC motor 14 The voltage Vr obtained by adding the spring force compensation voltage Vs to the applied voltage (= Ke · Nr) of the DC motor 14 that is the same is supplied to the DC motor 14 as the drive applied voltage V.

  For this reason, when the target position Pt of the throttle valve 3 matches the predicted position Pe, the applied voltage V for driving becomes substantially zero Vs, and the substantial voltage supply to the DC motor 14 (actuates the throttle valve 3). Voltage supply) is stopped, and the DC motor 14 is in the inertial rotation state. When the inertial rotation of the DC motor 14 ends, the throttle valve 3 reaches the target position Pt and converges.

  Therefore, the convergence of the position of the throttle valve 3 can be improved without performing a complicated process of switching the control gain as in the prior art. Further, since it is not necessary to perform an operation of verifying that the control gain is appropriate in each of a plurality of situations at the time of development, the development operation is facilitated.

  Further, since the processing of S110 and S140 in FIG. 3 is performed, the control accuracy of the throttle valve 3 can be improved as described with reference to FIG. Further, since the spring force compensation voltage Vs is calculated according to the actual position P of the throttle valve 3 (S103, S105), the control accuracy of the throttle valve 3 is improved by correctly taking into account the influence of the urging force of the spring 16. be able to.

  In the present embodiment, the target position determination unit 10a realized by the microcomputer 10 executing the target position determination process corresponds to the target position determination means, and the drive control process in FIG. 3 corresponds to the drive control means. is doing. In the drive control process of FIG. 3, S105 corresponds to the urging force compensation voltage calculation means, S110 to S140 correspond to the prediction means, S150 corresponds to the required rotational speed calculation means, and S160 corresponds to the required voltage calculation means. It corresponds to. Further, S103 in FIG. 3 corresponds to the position detecting means, and the spring 16 corresponds to the biasing means.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to such Embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect. .

  For example, when there is no spring 16 or when the urging force (spring force) is weak even when the spring 16 is present and it is not necessary to consider the urging force, S105 in FIG. 3 is deleted, and S120 and S160 are deleted. In each of the above, calculation may be performed with “Vs” in Expression 10 and Expression 13 set to 0. Further, instead of the spring 16, another urging member such as rubber or a hydraulic damper may be used.

  On the other hand, if it is guaranteed that the required voltage Vr calculated in S160 in FIG. 3 is always equal to or lower than the battery voltage Vb (for example, if Ts is sufficiently long, or the amount of change in the target position Pt is limited). In the case of S170 in FIG. 3, the required voltage Vr may always be determined as the drive application voltage V.

  DESCRIPTION OF SYMBOLS 1 ... Engine (internal combustion engine), 2 ... Intake passage, 3 ... Throttle valve, 4 ... Position sensor, 5 ... Accelerator pedal, 6 ... Accelerator opening sensor, 10 ... Microcomputer, 10a ... Target position determination part, 11 ... ECU ( Throttle valve control device), 13 ... reduction gear, 14 ... DC motor, 15 ... pinion gear, 16 ... return spring

Claims (5)

A throttle valve control device for controlling the throttle valve by driving a DC motor for operating a throttle valve of an internal combustion engine,
Target position determining means for determining a target position of the throttle valve;
A driving application voltage to be applied to the DC motor to determine the position of the throttle valve to the determined target position is determined every predetermined time, and the determined driving application voltage is determined to be the DC motor. Drive control means for supplying to,
Further, the drive control means is a means for determining the drive applied voltage,
The no-load rotation speed of the DC motor corresponding to the drive application voltage is calculated from the previously determined drive application voltage, and the throttle valve position prediction value is calculated from the calculated no-load rotation speed. A prediction means for calculating a predicted position;
In accordance with the difference between the target position and the predicted position calculated by the prediction means, the throttle valve is operated toward the target position by the difference over the constant time, and the DC motor has a constant rotational speed. Required rotational speed calculation means for calculating the required rotational speed,
A request for calculating, as a required voltage, an applied voltage of the DC motor corresponding to a requested no-load rotational speed, which is the no-load rotational speed of the DC motor, having the same value as the requested rotational speed calculated by the required rotational speed calculating means. Voltage calculating means, and
The drive control means determines the required voltage calculated by the required voltage calculation means as the drive application voltage;
A throttle valve control device characterized by the above. In the throttle valve control device according to claim 1,
The drive control means determines the maximum voltage as the drive applied voltage if the required voltage calculated by the required voltage calculation means exceeds the maximum voltage that can be supplied to the DC motor, and the required voltage If the required voltage calculated by the calculating means is less than or equal to the maximum voltage, determining the required voltage as the applied voltage for driving;
A throttle valve control device characterized by the above. In the throttle valve control device according to claim 1 or 2,
A position detecting means for detecting an actual position which is an actual position of the throttle valve;
The predicting means determines whether or not the throttle valve has stopped based on a change in the actual position detected by the position detecting means, and if it is determined that the throttle valve has stopped, the detection is detected. The actual position as the predicted position,
A throttle valve control device characterized by the above. In the throttle valve control device according to any one of claims 1 to 3,
The throttle valve is provided with a biasing means that applies a biasing force for returning the throttle valve to a reference position.
The drive control means compensates an urging force, which is a voltage applied to the DC motor, so that the DC motor applies a force having the same magnitude as the urging force and in a direction opposite to the urging force to the throttle valve. An urging force compensation voltage calculating means for calculating a voltage;
The prediction means corresponds to the corrected applied voltage using a corrected applied voltage that is a voltage obtained by subtracting the biasing force compensation voltage calculated by the biasing force compensation voltage calculating means from the previously determined driving application voltage. The no-load rotation speed of the DC motor is calculated, and the predicted position is calculated from the calculated no-load rotation speed,
The required voltage calculation means calculates, as the required voltage, a voltage obtained by adding the urging force compensation voltage calculated by the urging force compensation voltage calculation means to the applied voltage of the DC motor corresponding to the required no-load rotation speed. To do,
A throttle valve control device characterized by the above. In the throttle valve control device according to claim 4,
In the urging means, the urging force changes according to the position of the throttle valve,
The throttle valve control device includes position detection means for detecting an actual position which is an actual position of the throttle valve,
The biasing force compensation voltage calculation means calculates the biasing force compensation voltage based on the actual position detected by the position detection means;
A throttle valve control device characterized by the above.

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