JP5678908B2 - Throttle control system, throttle valve control device, throttle device, and throttle valve control method - Google Patents

Description

  The present invention relates to a throttle control system, a throttle valve control device, a throttle device, and a throttle valve control method for controlling a throttle valve of an internal combustion engine.

  An electronic throttle control device that electrically controls the opening of a throttle valve sets a target throttle opening according to the amount of operation of an accelerator pedal, and the opening of the throttle valve (hereinafter referred to as the throttle opening) is the target throttle opening. The throttle motor is controlled to match the degree.

  A return spring that urges the throttle valve is attached to the throttle valve controlled by the electronic throttle control device in order to obtain a throttle opening that is set in advance so as to obtain an engine output required for limp home travel. ing.

  Thus, for example, when an abnormality occurs in which the throttle opening cannot be controlled according to the amount of operation of the accelerator pedal, when the electronic throttle control device stops energizing the throttle motor, the return spring is responsive to the urging force. The throttle opening is set. For this reason, it becomes possible to ensure the minimum required engine output in the vehicle running when the abnormality occurs.

  However, if the above abnormality occurs in a situation where the return spring is broken and the electronic throttle control device stops energizing the throttle motor, there is a possibility that the throttle opening according to the urging force of the return spring cannot be set. . For this reason, it is necessary to detect breakage of the return spring.

  As a technique for detecting breakage of the return spring, there is known a technique for determining an abnormality of the return spring by stopping energization of the motor during the deceleration fuel cut operation of the engine (see, for example, Patent Document 1). ).

Japanese Patent Laid-Open No. 11-257103

However, since the technique described in Patent Document 1 requires a determination start condition that the fuel cut operation is in progress, the opportunity to perform abnormality detection is limited.
In the technique described in Patent Document 1, it is necessary to close the throttle valve by stopping energization of the motor after opening the throttle valve during the fuel cut operation. This may make it difficult to ensure drivability in engine control. In addition, the air amount control cannot be executed immediately in response to the fuel cut return request by the failsafe process, and there is a concern that acceleration delay and torque fluctuation may occur. Furthermore, operating the throttle while the engine is running may cause problems such as the negative pressure in the intake manifold fluctuates and the braking effectiveness changes, or a deceleration shock occurs due to a change in pumping loss. The

  The present invention has been made in view of these problems, and an object of the present invention is to provide a technique capable of detecting breakage of a return spring without stopping a throttle motor while the vehicle is traveling.

  In order to achieve the above object, the invention according to claim 1 is a throttle valve of an internal combustion engine, an actuator for operating the throttle valve, and an opening degree set in advance so as to enable limp home travel. A throttle control system having an urging member for applying an urging force to the throttle valve to return the throttle valve to an opener opening, and a throttle valve control device for controlling the throttle valve by driving an actuator. The determining means determines the target throttle opening that is the target opening of the throttle valve, and the PID control means is the target throttle opening determined by the target opening determining means and the actual throttle opening that is the opening of the throttle valve. The control amount expressed by the sum of the proportional term, integral term, and derivative term is calculated so that the degree matches. Then, it executes the PID control for controlling the throttle valve based on the control amount.

  Whether or not an abnormality determination condition set in advance is established for determining whether or not an abnormality has occurred in the biasing member based on the value of the integral term calculated by the PID control means. When the failure determination means determines that the abnormality determination condition is satisfied, the failsafe means executes a preset failsafe process.

  In the throttle control system according to claim 1 configured as described above, in order to control the position of the throttle valve, not only the control for accelerating and decelerating the actuator but also the actuator against the urging force of the urging member is used. It is necessary to perform control to compensate for the driving force that is stationary, that is, the driving force that balances the biasing force of the biasing member. In the throttle control system according to claim 1, since the control amount of the throttle valve is calculated by PID control, the integral term of the control amount performs control to compensate for the driving force balanced with the urging force of the urging member. It will bear. That is, as the urging force of the urging member increases, the integral term of the control amount also increases.

  On the other hand, when the urging member is broken, the urging force of the urging member becomes 0 regardless of the throttle opening. That is, the integral term of the control amount when the biasing member is broken is compared with the integral term of the control amount when the biasing member is normal, by a value corresponding to the biasing force when the biasing member is normal. , Get smaller.

For this reason , in the throttle control system according to claim 1, as in claim 3, the value of the integral term calculated when the biasing member is broken is larger and the biasing member is normal. A value smaller than the integral term that is sometimes calculated is used as the abnormality determination value, and the abnormality determination condition is that the value of the integral term calculated by the PID control means is less than the abnormality determination value as described in claim 2. Thus, the abnormality of the urging member can be determined.

Therefore, it is possible to detect an abnormality of the biasing member without stopping the actuator that operates the throttle valve while the vehicle on which the internal combustion engine is mounted is traveling.
Note that the urging force data of the urging member can be easily obtained by measurement of the drawing of the throttle valve or actual machine, for example, an appropriate abnormality determination condition (for example, the above-mentioned Abnormality determination value) can be set, and highly accurate abnormality detection can be realized.

Further, in the throttle control system according to any one of claims 1 to 3 , as described in claim 4 , the abnormality determination condition is changed according to the state of the vehicle on which the throttle valve is mounted. It is good to be done. Thereby, an appropriate abnormality determination condition according to the state of the vehicle can be set, and highly accurate abnormality detection can be realized. For example, the throttle is configured to be kept warm by cooling water of the internal combustion engine in order to prevent freezing. And, according to the throttle temperature, the frictional force, the characteristics of the motor, etc. fluctuate, and the integral term of the control amount also fluctuates. Therefore, in the throttle control system according to claim 4 , as described in claim 5 , The state of the vehicle may be the cooling water temperature of the internal combustion engine.

Further, the throttle control system of claim 1, the abnormality determination start means, if predetermined abnormality determination start conditions are satisfied, make initiate determination of whether an abnormality determination condition is satisfied to the abnormality judgment means. As a result, in a situation where it is not appropriate to determine whether or not an abnormality has occurred in the biasing member, it is possible to prohibit the operation of the abnormality determination means and to realize highly accurate abnormality detection. .

Further, in the situation where the actual throttle opening is changing, the integral term of the control amount also varies, so it is not appropriate to determine whether or not an abnormality has occurred in the biasing member. Therefore, the throttle control system according to claim 1, abnormal determination start conditions, the actual throttle opening degree is not changed continuously preset static determination time.

  By the way, the integral gain that determines the integral term of the control amount works to reduce the deviation between the target throttle opening and the actual throttle opening. Therefore, if this integral gain is fixed to a large value, when the actual throttle opening converges near the target throttle opening, the actual throttle opening can be made to coincide with the target throttle opening. When the deviation from the throttle opening is large, this large deviation is accumulated. Therefore, the integral term becomes too large, and the actual throttle opening is greatly hunted near the target throttle opening, so that the actual throttle opening is targeted. It takes time to converge to the throttle opening.

Therefore, in the throttle control system according to any one of claims 1 to 5 , as described in claim 6 , the PID control means performs the operation when the actual throttle opening is near the target throttle opening. The integral term is preferably calculated so that the value of the integral term is larger than when the actual throttle opening is not near the target throttle opening.

  In the throttle control system configured as described above, the integral term can be prevented from becoming too large, and the actual throttle opening can be restrained from hunting largely around the target throttle opening. That is, the actual throttle opening can be converged to the target throttle opening in a short time, the integral term can be converged in a short time, and the value of the integral term can be determined in a short period. As a result, it is possible to shorten the time required to determine whether or not the urging member is abnormal.

Further, in the throttle control system according to any one of claims 1 to 6 , as described in claim 7 , the fail-safe means performs the actual throttle opening to the opener opening as fail-safe processing. The feedback control is performed so as to match, and the feedback control may be different from the PID control executed by the PID control means.

  In the throttle control system configured as described above, it is possible to perform appropriate feedback control according to each situation when the urging member is not abnormal and when the urging member is abnormal. For example, when the urging member is not abnormal, feedback control is performed with emphasis on followability so that the actual throttle opening coincides with the target throttle opening in a short period, while the urging member is abnormal. In some cases, feedback control with an emphasis on stability may be performed in order to ensure that the actual throttle opening coincides with the opener opening.

Further, in the throttle control system according to any one of claims 1 to 6 , when the fail-safe means does not satisfy the abnormality determination condition as the fail-safe process as described in claim 8. compared to, by executing the ignition retard control for retarding the ignition timing of the internal combustion engine, may be allowed to lower the output of the internal combustion engine, as claimed in claim 9, the internal combustion engine is a multiple As a fail-safe process, the output of the internal combustion engine may be reduced by reducing the number of cylinders that supply fuel as compared with the case where the abnormality determination condition is not satisfied.

In the throttle control system configured as described above, limp home traveling can be performed by reducing the output of the internal combustion engine by a method other than the throttle control.
According to a tenth aspect of the present invention, the throttle valve is returned to an opener opening degree that is set in advance so as to enable limp home travel by driving an actuator that operates the throttle valve of the internal combustion engine. A throttle valve control device for controlling a throttle valve to which a biasing member for applying a biasing force to the throttle valve is attached, wherein the target opening determining means determines a target throttle opening that is a target opening of the throttle valve The proportional term, integral term and differential term are set so that the target throttle opening determined by the target opening determining means matches the actual throttle opening which is the throttle valve opening. A control amount expressed by the sum is calculated, and PID control for controlling the throttle valve based on the control amount is executed.

Whether or not an abnormality determination condition set in advance is established for determining whether or not an abnormality has occurred in the biasing member based on the value of the integral term calculated by the PID control means. When the failure determination means determines that the abnormality determination condition is satisfied, the failsafe means executes a preset failsafe process. In addition, when the abnormality determination start condition set in advance is satisfied, the abnormality determination start means causes the abnormality determination means to start determining whether or not the abnormality determination condition is satisfied. The abnormality determination start condition is that the actual throttle opening does not change continuously for a preset stationary determination time.

The throttle valve control device according to the tenth aspect configured as described above can achieve the same effect as the throttle control system according to the first aspect.
According to the eleventh aspect of the present invention, the throttle valve is returned to an opener opening degree that is an opening degree that is set in advance so as to enable limp home travel, a throttle valve of the internal combustion engine, an actuator that operates the throttle valve, and limp home travel. A throttle device that controls the throttle valve by driving an actuator, wherein the target opening degree determining means is a target opening degree of the throttle valve. The throttle opening is determined, and the PID control means causes the proportional term and the integral term so that the target throttle opening determined by the target opening determining means matches the actual throttle opening that is the opening of the throttle valve. PID control that controls the throttle valve based on the control amount is calculated. To.

Whether or not an abnormality determination condition set in advance is established for determining whether or not an abnormality has occurred in the biasing member based on the value of the integral term calculated by the PID control means. When the failure determination means determines that the abnormality determination condition is satisfied, the failsafe means executes a preset failsafe process. In addition, when the abnormality determination start condition set in advance is satisfied, the abnormality determination start means causes the abnormality determination means to start determining whether or not the abnormality determination condition is satisfied. The abnormality determination start condition is that the actual throttle opening does not change continuously for a preset stationary determination time.

The throttle device according to claim 11 configured as described above can achieve the same effect as the throttle control system according to claim 1.
According to a twelfth aspect of the present invention, the throttle valve is returned to an opener opening degree that is set in advance so that limp home travel is enabled by driving an actuator that operates the throttle valve of the internal combustion engine. A throttle valve control method for controlling a throttle valve to which a biasing member for applying a biasing force to the throttle valve is attached, and determining a target throttle opening that is a target opening of the throttle valve in a target opening determination procedure In the PID control procedure, the proportional term, the integral term, and the differential term are set so that the target throttle opening determined by the target opening determination procedure matches the actual throttle opening that is the throttle valve opening. A control amount expressed by the sum is calculated, and PID control for controlling the throttle valve based on the control amount is executed.

In the abnormality determination procedure, whether or not a predetermined abnormality determination condition is established to determine whether an abnormality has occurred in the biasing member based on the value of the integral term calculated by the PID control procedure. When the abnormality determination procedure determines that the abnormality determination condition is satisfied in the fail-safe procedure, a fail-safe process set in advance is executed. Further, when a preset abnormality determination start condition is satisfied in the abnormality determination start procedure , the abnormality determination procedure is started to determine whether or not the abnormality determination condition is satisfied. The abnormality determination start condition is that the actual throttle opening does not change continuously for a preset stationary determination time.

The throttle valve control method is a method performed by the invention according to claims 1 to 11, by performing the method, the same effect as the invention described in claims 1 to 11 Can be obtained.

1 is a schematic configuration diagram showing an engine control system 1. FIG. FIG. 3 is a diagram showing a schematic configuration of a throttle valve 130. It is a flowchart which shows a throttle control process. It is a figure which shows the correspondence of the urging | biasing force of the return spring 134, and throttle opening.

Embodiments of the present invention will be described below with reference to the drawings.
The engine control system 1 is mainly composed of an engine 100 and an electronic control unit (hereinafter referred to as ECU) 2 that controls the engine 100.

  The engine 100 is an internal combustion engine mounted on a vehicle. As shown in FIG. 1, a combustion chamber 104 is formed for each cylinder by a cylinder 101, a piston 102, and a cylinder head 103. A spark plug 105 for igniting the fuel is attached in the combustion chamber 104.

An intake pipe 120 is connected to the combustion chamber 104 of the engine 100 via an intake valve 106, and an exhaust pipe 140 is connected via an exhaust valve 107.
The intake pipe 120 is provided with a throttle valve 130 that adjusts the amount of air supplied to the engine 100. The intake pipe 120 is connected to each cylinder of the engine 100 via an intake manifold 121, and the air whose amount is adjusted by the throttle valve 130 through the intake pipe 120 passes through the intake manifold 121 and passes through the engine. Distribution is supplied to each of the 100 cylinders.

  The intake manifold 121 is provided with an injector 122 for each cylinder of the engine 100. The fuel injected from the injector 122 is mixed with air from the intake pipe 120 and supplied to each cylinder of the engine 100.

  Further, in each cylinder of the engine 100, the air-fuel mixture is introduced into the combustion chamber 104 as the intake valve 106 is opened and closed, and the introduced air-fuel mixture is combusted by ignition of the ignition plug 105, whereby the piston 102 is pushed down. Torque is applied to the crankshaft 108 of the engine 100. The exhaust gas after combustion is discharged to the outside through the exhaust pipe 140 as the exhaust valve 107 is opened and closed.

  Further, the engine 100 includes a water temperature sensor 109 that detects a cooling water temperature of the engine 100, a crank angle sensor 110 that detects the rotation angle of the crankshaft 108 of the engine 100, and an intake pipe as sensors for detecting the operating state. An air flow meter 123 that detects the amount of air supplied to the engine 100 through 120, a throttle opening sensor 124 that detects the opening of the throttle valve 130, and an intake pressure sensor 125 that detects the pressure in the intake pipe 120 An air-fuel ratio sensor 141 that detects the air-fuel ratio of the fuel mixture supplied to the engine 100 from the oxygen concentration in the exhaust gas is provided.

Further, an accelerator opening sensor 161 that detects the amount of depression of the accelerator pedal 160 (accelerator opening) is provided in a vehicle on which the engine 100 is mounted.
The ECU 2 also includes a microcomputer 3 that executes processing for controlling the engine 100, a drive circuit 4 that operates various actuators according to control signals from the microcomputer 3, and an input circuit that inputs various signals to the microcomputer 3. And 5.

  The microcomputer 3 includes a signal from the water temperature sensor 109, a signal from the crank angle sensor 110, a signal from the air flow meter 123, a signal from the throttle opening sensor 124, a signal from the intake pressure sensor 125, and an air-fuel ratio sensor 141. And the signal from the accelerator opening sensor 161 are input via the input circuit 5. The input circuit 5 is a general one, and can be processed by the microcomputer 3 by performing predetermined signal processing such as analog / digital conversion, noise removal, waveform shaping, etc., on a signal such as a sensor signal. Convert input signal to signal.

  The microcomputer 3 detects the state of the engine 100 based on the above signals input via the input circuit 5, and outputs a control signal to the drive circuit 4 based on the detection result, thereby allowing each cylinder The engine 100 is operated by controlling various actuators such as a spark plug 105, an injector 122 in each cylinder, and a throttle motor 131 that changes the opening of the throttle valve 130.

  Further, an abnormality notification lamp (MIL; Malfunction Indicator Lamp) 170 for notifying the driver of the result of abnormality detection or the like is connected to the ECU 2 via the drive circuit 4. Then, ECU 2 turns on MIL 170 by outputting a lighting signal to MIL 170.

  As shown in FIG. 2, the throttle valve 130 is configured to be rotatable about the rotation shaft 132, and rotational torque from the throttle motor 131 is transmitted to the rotation shaft 132 via the reduction gear 133. An opening / closing operation is performed in the intake pipe 120, and the throttle opening changes.

  A return spring 134 is attached to the rotating shaft 132. The return spring 134 urges the rotating shaft 132 so as to have a throttle opening degree (hereinafter referred to as an opener opening degree) set in advance so that an engine output capable of limp home traveling is obtained. That is, even when the energization to the throttle motor 131 is stopped and the rotational torque is no longer transmitted to the rotating shaft 132, the throttle valve 130 is held at the opener opening, which is necessary for limp home travel. Intake amount is secured.

  Next, throttle control processing executed by the microcomputer 3 to control the throttle valve 130 will be described with reference to FIG. The throttle control process is a process that is repeatedly executed at regular intervals.

  When the throttle control process is executed, as shown in FIG. 3, the microcomputer 3 first determines whether or not an abnormality determination start condition preset in order to start the determination of the abnormality of the return spring 134 is established in S10. Judge whether or not. In the present embodiment, the abnormality determination start condition is that all of the following two conditions are satisfied. First, the first condition is “the throttle opening does not change continuously for a predetermined stationary determination time (for example, 1 second)”. The second condition is that “the difference between the throttle opening and the opener opening is equal to or larger than a preset abnormality determination start opening (for example, 5 °)”.

  If the abnormality determination start condition is not satisfied (S10: NO), the target throttle opening corresponding to the throttle control at the normal time is calculated in S20. That is, the throttle opening corresponding to the accelerator opening indicated by the signal from the accelerator opening sensor 161 is calculated as the target throttle opening.

  In S30, the target throttle opening calculated in S20 and the throttle opening sensor 124 from feedback control (PID control) using predetermined control gains (proportional gain Kp, integral gain Ki, differential gain Kd). The driving torque required for the throttle motor 131 (hereinafter referred to as required driving torque) is calculated so that the deviation from the throttle opening indicated by the signal (hereinafter also referred to as actual throttle opening) becomes zero. A signal indicating the torque amount of the drive torque is output to the drive circuit 4, and the throttle control process is temporarily terminated. As a result, a current corresponding to the required drive torque flows through the throttle motor 131, and the throttle motor 131 generates a rotational torque corresponding to the current value. Then, by rotating the throttle valve 130 via the reduction gear 133 by this rotational torque, the throttle valve 130 is operated so that the throttle opening matches the target throttle opening.

  In the PID control of S30, the proportional term is (Kp · Δθ), the integral term is (Ki · ∫Δθ), and the differential term is (Kd · dΔθ / dt). Based on the above, the required drive torque is calculated.

Required drive torque = Kp · Δθ + Ki · ∫Δθ + Kd · dΔθ / dt (1)
Incidentally, the integral gain Ki that determines the integral term (Ki · ∫Δθ) of the required drive torque works to reduce the deviation between the target throttle opening and the actual throttle opening. Therefore, if this integral gain Ki is fixed to a large value, when the actual throttle opening converges near the target throttle opening, the actual throttle opening can be made to coincide with the target throttle opening. When the deviation from the target throttle opening is large, this large deviation is accumulated. Therefore, the integral term becomes too large, and the actual throttle opening is greatly hunted near the target throttle opening. It takes time to converge to the target throttle opening.

  Therefore, in the PID control of S30, when the deviation between the actual throttle opening and the target throttle opening is equal to or greater than a preset deviation determination value indicating that the actual throttle opening is near the target throttle opening. The integral gain Ki is set to a first predetermined value, while if the deviation is less than the deviation determination value, the integral gain Ki is set to a second predetermined value that is greater than the first predetermined value. Thereby, generation | occurrence | production of the said hunting is suppressed.

  Next, in S10, when the abnormality determination start condition is satisfied (S10: YES), a return spring abnormality determination process is performed in S40 to determine whether or not an abnormality has occurred in the return spring 134.

  Specifically, the latest calculated integral term of the required drive torque calculated in the processing of S60 described later is extracted, and the value of the extracted integral term is less than a preset abnormality determination value. In some cases, it is determined that an abnormality has occurred in the return spring 134.

The reason why the abnormality of the return spring 134 can be determined by whether or not the value of the integral term is less than the abnormality determination value will be described below.
In order to control the position of the throttle valve 130, not only the torque for accelerating and decelerating the throttle motor 131 but also the torque for stopping the throttle motor 131 against the urging force of the return spring 134, that is, the attachment of the return spring 134. It is necessary to perform control to compensate for torque that balances with the power (hereinafter also referred to as load torque compensation control). In this embodiment, since the required drive torque is calculated by PID control, the integral term of the required drive torque is responsible for load torque compensation control. That is, as the urging force of the return spring 134 increases, the integral term of the required drive torque also increases.

  And the urging | biasing force of the return spring 134 is comprised so that it may become 0 by an opener opening degree, as shown in FIG. Further, the biasing force of the return spring 134 has a large change amount with respect to the change in the throttle opening when the throttle opening is in the vicinity of the opener opening, and the difference between the throttle opening and the opener opening is not less than a predetermined value. In some cases, the amount of change with respect to the change in throttle opening is small. That is, when the difference between the throttle opening and the opener opening is equal to or greater than a predetermined value, the integral term of the required drive torque has a small change amount with respect to the throttle opening.

  On the other hand, when the return spring 134 is broken, the urging force of the return spring 134 becomes zero regardless of the throttle opening. In other words, the integral term of the required drive torque when the return spring 134 is broken corresponds to the biasing force of the return spring 134 when it is normal compared to the integral term of the required drive torque when the return spring 134 is normal. Decreases by the value.

  Therefore, by setting a value larger than the value of the integral term calculated when the return spring 134 is broken and smaller than the integral term calculated when the return spring 134 is normal as the abnormality determination value. The abnormality of the return spring 134 can be determined.

  For example, as shown in FIG. 4, the microcomputer 3 stores urging force map data indicating the correspondence between the urging force of the return spring 134 and the throttle opening. The data of the urging force map is acquired by drawing the throttle valve 130 or measuring it with an actual machine.

  Further, the microcomputer 3 stores data of a determination ratio map indicating a correspondence relationship between the coolant temperature of the engine 100 and an abnormality determination ratio (described later). In this determination ratio map, the abnormality determination ratio is set lower as the coolant temperature of the engine 100 becomes higher. For example, the abnormality determination ratio when the cooling water temperature is 0 ° C. is 50%, and the abnormality determination ratio when the cooling water temperature is 80 ° C. is 10%.

  In S40, an urging force of the return spring 134 corresponding to the throttle opening detected by the throttle opening sensor 124 (hereinafter referred to as an abnormality determining urging force) is calculated with reference to the urging force map, and the water temperature sensor 109 is calculated. The abnormality determination ratio corresponding to the coolant temperature detected by the above is calculated with reference to the determination ratio map. Thereafter, a value obtained by multiplying the calculated abnormality determination biasing force and the abnormality determination ratio is set as the abnormality determination value. For this reason, when compared with the same throttle opening, the abnormality determination value decreases as the cooling water temperature increases. This is because the integral term of the required drive torque may become larger at a low temperature where freezing may occur than at a high temperature.

Thereafter, as described above, when the value of the extracted integral term is less than the abnormality determination value, it is determined that an abnormality has occurred in the return spring 134.
When the process of S40 is completed, as shown in FIG. 3, it is determined in S50 whether or not the return spring 134 is determined to be abnormal in the return spring abnormality determination process of S40. If the return spring 134 is not abnormal (S50: NO), the target throttle opening corresponding to the normal throttle control is calculated in S60 in the same manner as in S20, and further in S70. The feedback control similar to S30 is executed, and the throttle control process is temporarily terminated.

  On the other hand, if the return spring 134 is abnormal (S50: YES), the target throttle opening corresponding to the throttle control at the time of abnormality is calculated in S80. Specifically, the opener opening is calculated as the target throttle opening.

  In S90, the target throttle opening calculated in S80 and the throttle opening sensor 124 from the throttle opening sensor 124 by feedback control (PID control) using predetermined control gains (proportional gain Kp, integral gain Ki, differential gain Kd). The required drive torque is calculated so that the deviation from the throttle opening (actual throttle opening) indicated by the signal becomes zero.

  In S90, control gains (proportional gain Kp, integral gain Ki, differential gain Kd) different from S30 are applied, and these control gains Kp, Ki, Kd are compared with the control gains in S30. It is set so that stability is more important than responsiveness of throttle control.

Thereafter, in S100, a lighting signal is output to MIL 170, and the throttle control process is temporarily terminated.
In the engine control system 1 configured as described above, a throttle valve 130 that adjusts the amount of air supplied to the engine 100, a throttle motor 131 that operates the throttle valve 130, and a limp home traveling are set in advance. A return spring 134 for applying an urging force to the throttle valve 130 to return the throttle valve 130 to the opened opening degree, and an ECU 2 for controlling the throttle valve 130 by driving the throttle motor 131. A target opening (target throttle opening) is determined (S60), and a proportional term and an integral term are set so that the determined target throttle opening matches the opening of the throttle valve 130 (actual throttle opening). Calculate the required drive torque expressed as the sum of the differential term, It executes a PID control for controlling the throttle valve 130 based on the demanded driving torque (S70).

  Then, it is determined whether or not the integral term calculated by the PID control is less than a preset abnormality determination value (S40), and when it is determined that the integral term is less than the abnormality determination value (S50: YES). ) As a fail-safe process, feedback control is executed so that the actual throttle opening coincides with the opener opening (S80, S90).

  Accordingly, it is possible to detect an abnormality of the return spring 134 without stopping the throttle motor 131 that operates the throttle valve 130 while the vehicle is traveling.

  It should be noted that the biasing force data (biasing force map data) of the return spring 134 is acquired from the drawing of the throttle valve 130 or measurement by an actual machine, so that an appropriate abnormality determination value can be set, and the accuracy is high. Abnormality detection can be realized.

  Further, the throttle valve 130 is configured to be kept warm by the cooling water of the engine 100 in order to prevent freezing, and the frictional force, the characteristics of the throttle motor 131 and the like vary according to the temperature of the throttle valve 130, The integral term of the required drive torque also varies. For this reason, the abnormality determination value is changed according to the cooling water temperature of engine 100, so that the abnormality detection with high accuracy can be realized.

  In addition, “the throttle opening is not continuously changed for a preset stationary determination time” and “the throttle opening is outside a preset range indicating that the throttle opening is in the vicinity of the opener opening”. When all of the conditions are satisfied (S10: YES), a determination is made as to whether or not an abnormality has occurred in the return spring 134 (S40).

  As a result, in a situation where it is not appropriate to determine whether or not an abnormality has occurred in the return spring 134, it is possible to prohibit abnormality determination, and to realize highly accurate abnormality detection.

  When the actual throttle opening is in the vicinity of the opener opening, the change in the urging force of the return spring 134 with respect to the change in the actual throttle opening is compared with the case in which the actual throttle opening is not in the vicinity of the opener opening. Since it is very large, it is not appropriate to determine whether or not an abnormality has occurred in the return spring 134. Further, in the situation where the actual throttle opening is changing, the integral term of the required drive torque also fluctuates, so it is not appropriate to determine whether or not an abnormality has occurred in the return spring 134.

  If it is determined that the return spring 134 is abnormal (S40: YES), feedback control is performed so that the actual throttle opening coincides with the opener opening as fail-safe processing (S80, S90). The feedback control is different from the throttle opening degree feedback control (S70) when the return spring 134 is not abnormal. As a result, it is possible to perform appropriate feedback control according to the respective situations when the return spring 134 is not abnormal and when the return spring 134 is abnormal. In the present embodiment, when the return spring 134 is not abnormal, feedback control is performed with emphasis on followability so that the actual throttle opening coincides with the target throttle opening in a short period of time. If 134 is abnormal, feedback control is performed with emphasis on stability in order to ensure that the actual throttle opening coincides with the opener opening.

  In the embodiment described above, the engine control system 1 is the throttle control system according to the present invention, the ECU 2 is the throttle valve control device according to the present invention, the engine 100 is the internal combustion engine according to the present invention, the throttle motor 131 is the actuator according to the present invention, and the return spring 134. Is an urging member in the present invention.

  The process of S60 is the target opening determination means and the target opening determination procedure in the present invention, the process of S70 is the PID control means and the PID control procedure in the present invention, and the process of S40 is the abnormality determination means and the abnormality determination procedure in the present invention. , S80 and S90 are fail-safe means and fail-safe procedures in the present invention, and S10 is abnormality determination start means in the present invention.

The required drive torque is an abnormality determination condition in the present invention that the control amount in the present invention and the value of the integral term of the required drive torque are less than the abnormality determination value.
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, As long as it belongs to the technical scope of this invention, a various form can be taken.

  For example, in the embodiment described above, the abnormality determination value is changed according to the engine coolant temperature. However, the abnormality determination time set for determining whether or not an abnormality has occurred in the return spring 134 may be changed according to the state of the vehicle.

  For example, if the state where the integral term of the required drive torque is less than the abnormality determination value continues for a preset abnormality determination time, it is mounted on the vehicle when determining that “an abnormality has occurred in the return spring 134”. The abnormality determination time may be changed according to the battery voltage. Specifically, for example, when the battery voltage is 12.5 V, 13.5 V, and 14.0 V, the abnormality determination time is set to 2000 ms, 100 ms, and 50 ms, respectively. The abnormality determination time is changed in accordance with the battery voltage because, for example, in a state where the power consumption in the vehicle increases and the battery voltage is not stable, the driving torque of the throttle motor 131 fluctuates and feedback control (PID control) occurs. This is because the required drive torque calculated in step) is not stable.

  In the above embodiment, when the return spring 134 is abnormal (S50: YES), the actual throttle opening is feedback-controlled so as to coincide with the opener opening (S80, S90) to perform limp home travel. showed that. However, in order to perform limp home travel when the return spring 134 is abnormal, the ignition delay control is performed to delay the ignition timing of the engine 100 as compared with the case where the return spring 134 is not abnormal. The output may be reduced, or the output of engine 100 may be reduced by decreasing the number of cylinders that supply fuel. Further, the engine 100 may be stopped when the return spring 134 is abnormal.

  Moreover, in the said embodiment, the control system containing the throttle valve 130 and the microcomputer 3 which controls the throttle valve 130 was shown. However, in a throttle device that includes a throttle valve 130, a throttle motor 131 that operates the throttle valve 130, and a microcomputer that controls the throttle motor 131, the microcomputer may execute the throttle control process shown in FIG. Good.

  DESCRIPTION OF SYMBOLS 1 ... Engine control system, 2 ... ECU, 3 ... Microcomputer, 4 ... Drive circuit, 5 ... Input circuit, 100 ... Engine, 101 ... Cylinder, 102 ... Piston, 103 ... Cylinder head, 104 ... Combustion chamber, 105 ... Spark plug , 106 ... intake valve, 107 ... exhaust valve, 108 ... crankshaft, 109 ... water temperature sensor, 110 ... crank angle sensor, 120 ... intake pipe, 121 ... intake manifold, 122 ... injector, 123 ... air flow meter, 124 ... throttle open Degree sensor, 125 ... Intake pressure sensor, 130 ... Throttle valve, 131 ... Throttle motor, 132 ... Rotating shaft, 133 ... Reduction gear, 134 ... Return spring, 140 ... Exhaust pipe, 141 ... Air-fuel ratio sensor, 160 ... Accelerator pedal, 161: accelerator opening sensor

Claims (12)

A throttle valve for an internal combustion engine, an actuator for operating the throttle valve, and an urging force for returning the throttle valve to an opener opening degree that is a predetermined opening degree so that limp home travel is possible. A throttle control system having a biasing member applied to the throttle valve and a throttle valve control device that controls the throttle valve by driving the actuator,
Target opening determining means for determining a target throttle opening which is a target opening of the throttle valve;
The target throttle opening determined by the target opening determining means is represented by the sum of a proportional term, an integral term, and a differential term so that the actual throttle opening that is the opening of the throttle valve matches. PID control means for calculating a control amount and executing PID control for controlling the throttle valve based on the control amount;
Based on the value of the integral term calculated by the PID control means, it is determined whether or not an abnormality determination condition set in advance for determining whether or not an abnormality has occurred in the biasing member is satisfied. Abnormality determination means,
A fail-safe unit that executes a preset fail-safe process when the abnormality determination unit determines that the abnormality determination condition is satisfied ;
When a predetermined abnormality determination start condition is satisfied, the abnormality determination start unit is configured to start the determination of whether the abnormality determination condition is satisfied or not.
The abnormality determination start condition is
The throttle control system according to claim 1, wherein the actual throttle opening does not continuously change for a preset stationary determination time . The abnormality determination condition is
The value of the integral term calculated by the PID control means is less than a preset abnormality determination value.
The throttle control system according to claim 1. A value larger than the value of the integral term calculated when the urging member is broken and smaller than the integral term calculated when the urging member is normal is set as the abnormality determination value.
The throttle control system according to claim 2. The abnormality determination condition is
The throttle control system according to any one of claims 1 to 3, wherein the throttle control system is changed according to a state of a vehicle on which the throttle valve is mounted. The throttle control system according to claim 4 , wherein the state of the vehicle is a cooling water temperature of the internal combustion engine. The PID control means includes
When the actual throttle opening is in the vicinity of the target throttle opening, the integral term is larger so that the value of the integral term is larger than in the case where the actual throttle opening is not in the vicinity of the target throttle opening. The throttle control system according to any one of claims 1 to 5 , wherein the throttle control system is calculated. The failsafe means is:
As the fail-safe process, feedback control is performed so that the actual throttle opening coincides with the opener opening,
The throttle control system according to any one of claims 1 to 6 , wherein the feedback control is different from PID control executed by the PID control means. The failsafe means is:
As the fail-safe process, the output of the internal combustion engine is reduced by executing an ignition delay control that delays the ignition timing of the internal combustion engine as compared with a case where the abnormality determination condition is not satisfied. The throttle control system according to any one of claims 1 to 6 . The internal combustion engine is composed of a plurality of cylinders,
The failsafe means is:
As the fail-safe processing, the abnormality determination condition as compared with the case where not established, by reducing the cylinder fuel supply, claims 1, characterized in that to reduce the output of the internal combustion engine 7. The throttle control system according to any one of items 6 . By driving an actuator that operates the throttle valve of the internal combustion engine, an urging force for returning the throttle valve to an opener opening degree that is set in advance so as to enable limp home travel is applied to the throttle valve. A throttle valve control device for controlling the throttle valve to which a biasing member to be applied is attached,
Target opening determining means for determining a target throttle opening which is a target opening of the throttle valve;
The target throttle opening determined by the target opening determining means is represented by the sum of a proportional term, an integral term, and a differential term so that the actual throttle opening that is the opening of the throttle valve matches. PID control means for calculating a control amount and executing PID control for controlling the throttle valve based on the control amount;
Based on the value of the integral term calculated by the PID control means, it is determined whether or not an abnormality determination condition set in advance for determining whether or not an abnormality has occurred in the biasing member is satisfied. Abnormality determination means,
A fail-safe unit that executes a preset fail-safe process when the abnormality determination unit determines that the abnormality determination condition is satisfied ;
When a predetermined abnormality determination start condition is satisfied, the abnormality determination start unit is configured to start the determination of whether the abnormality determination condition is satisfied or not.
The abnormality determination start condition is
2. The throttle valve control device according to claim 1, wherein the actual throttle opening does not continuously change for a preset stationary determination time . A throttle valve for an internal combustion engine, an actuator for operating the throttle valve, and an urging force for returning the throttle valve to an opener opening degree that is a predetermined opening degree so that limp home travel is possible. A throttle device for controlling the throttle valve by driving the actuator,
Target opening determining means for determining a target throttle opening which is a target opening of the throttle valve;
The target throttle opening determined by the target opening determining means is represented by the sum of a proportional term, an integral term, and a differential term so that the actual throttle opening that is the opening of the throttle valve matches. PID control means for calculating a control amount and executing PID control for controlling the throttle valve based on the control amount;
Based on the value of the integral term calculated by the PID control means, it is determined whether or not an abnormality determination condition set in advance for determining whether or not an abnormality has occurred in the biasing member is satisfied. Abnormality determination means,
A fail-safe unit that executes a preset fail-safe process when the abnormality determination unit determines that the abnormality determination condition is satisfied ;
When a predetermined abnormality determination start condition is satisfied, the abnormality determination start unit is configured to start the determination of whether the abnormality determination condition is satisfied or not.
The abnormality determination start condition is
The throttle device according to claim 1, wherein the actual throttle opening does not change continuously for a preset stationary determination time . By driving an actuator that operates the throttle valve of the internal combustion engine, an urging force for returning the throttle valve to an opener opening degree that is set in advance so as to enable limp home travel is applied to the throttle valve. A throttle valve control method for controlling the throttle valve to which a biasing member to be applied is attached,
A target opening determination procedure for determining a target throttle opening which is a target opening of the throttle valve;
The target throttle opening determined by the target opening determination procedure is represented by the sum of a proportional term, an integral term, and a derivative term so that the actual throttle opening that is the opening of the throttle valve matches. A PID control procedure for executing a PID control for controlling the throttle valve based on the control amount;
Based on the value of the integral term calculated by the PID control procedure, it is determined whether or not an abnormality determination condition set in advance for determining whether or not an abnormality has occurred in the biasing member is satisfied. Abnormal judgment procedure;
When the abnormality determination procedure determines that the abnormality determination condition is satisfied, a failsafe procedure for executing a preset failsafe process;
An abnormality determination start procedure for starting the determination of whether or not the abnormality determination condition is satisfied in the abnormality determination procedure when a preset abnormality determination start condition is satisfied;
The abnormality determination start condition is
The throttle valve control method characterized in that the actual throttle opening does not continuously change for a preset stationary determination time.