JP2008196441A - Control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a learning value receiving influence of a failure from being continuously used after repair of an apparatus when the apparatus relating to control of a vehicle fails in relation to a control device for a vehicle executing learning control. <P>SOLUTION: The control device for the vehicle executing learning control for correcting error components regularly inheriting in parameters relating to control of the vehicle is provided with; nonvolatile memory capable of retaining stored date even if electric power supply is shut off; a learning value storage means storing learning value calculated in the learning control into a first storage device; a failure detection means detecting a failure of the apparatus relating to learning control, and a learning value delete means deleting learning value stored in the nonvolatile memory if a failure of the apparatus is detected by the failure detection means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle control apparatus in which learning control is performed, and more particularly to a vehicle control apparatus including a nonvolatile memory capable of electrically rewriting data.

  Conventionally, for example, as disclosed in Japanese Patent Application Laid-Open No. 10-252547, an SRAM that temporarily stores control data and a nonvolatile memory (hereinafter referred to as “EEPROM”) that can electrically rewrite data. There is known a vehicle control device including The SRAM is a memory that is backed up by a battery voltage, and the EEPROM is a memory that can retain stored data without being lost even when the power is cut off.

  In the above conventional vehicle control device, learning to evaluate past control results and correct control parameters and control logic to eliminate the influence of aging degradation and individual differences of the control target represented by sensors and actuators. Control is performed. In this learning control, the learning value stored in the SRAM is written into the EEPROM at an appropriate timing. Thereby, even when the learning value stored in the SRAM disappears, such as when the battery is cleared, the learning value calculated in the past can be continuously used by reading the data in the EEPROM.

Japanese Patent Laid-Open No. 10-252547 JP-A-6-75866

  By the way, in a vehicle control system, failure diagnosis control (diagnosis) of devices such as sensors and actuators related to vehicle control is performed. Thereby, it is supposed to notify a user of the failure of these apparatuses quickly and to effectively avoid the situation where the control of the vehicle is continued based on an erroneous sensor signal.

  Here, when a failure of the device is detected, there is a high possibility that the learning value of control related to the device is affected by the failure. For this reason, when the said apparatus is replaced | exchanged etc., a learning value cannot be used continuously. However, since the EPPROM is a non-volatile memory, the learning value stored in the memory does not disappear even if the power supply voltage is interrupted when the failed device is replaced. For this reason, if the learning value at the time of failure is continuously used after the system is restored, erroneous learning control is executed, and there is a possibility that problems such as the engine not starting may occur. In order to avoid such a situation, a method of manually erasing the learning value simultaneously with the exchange work is conceivable. However, since the system in recent years is very complicated, the number of work steps is greatly increased.

  The present invention has been made to solve the above-described problems. When a failure occurs in a device related to vehicle control, the learning value affected by the failure continues after the repair of the device. It is an object of the present invention to provide a control device for a vehicle that can be prevented from being used.

In order to achieve the above object, a first invention is a control device for a vehicle,
In a vehicle control apparatus that executes learning control for correcting an error component that is steadily included in a parameter related to vehicle control,
A first storage device capable of holding stored data even when power supply is interrupted;
Learning value storage means for storing the learning value calculated in the learning control in the first storage device;
A failure detection means for detecting a failure of the device related to the learning control;
When a failure of the device is detected by the failure detection means, learned value erasure means for erasing the learned value stored in the first storage device;
It is characterized by providing.

The second invention is the first invention, wherein
The first storage device is a nonvolatile memory capable of electrically rewriting data.

The third invention is the first or second invention, wherein
The learning value storage means stores the learning value stored in the second storage device that loses the stored data when power supply is interrupted as a backup in the first storage device. And
Learning value return means for returning the learning value stored in the first storage device to the second storage device when the power supply to the second storage device is restored after being interrupted once. It is characterized by providing.

Moreover, 4th invention is set in 3rd invention,
The apparatus further comprises learning value holding means for holding the learning value stored in the second storage device when a failure of the device is detected by the failure detecting means.

  According to the first invention, the learning value calculated in the learning control is stored in the first storage device. And when the failure of the apparatus which concerns on learning control is detected, the learning value memorize | stored in the 1st memory | storage device is erase | eliminated. For this reason, according to the present invention, it is possible to effectively avoid a situation in which the learning value affected by the failure of the device is continuously used after the device is repaired.

  According to the second invention, a nonvolatile memory (EEPROM) capable of electrically rewriting data can be used as the first storage device.

  According to the third invention, the learning value stored in the second storage device that loses the stored data when the power supply is interrupted is stored in the first storage device as a backup. Then, when the learning value of the second storage device disappears, the learning value stored in the first storage device is restored to the second storage device. For this reason, according to the present invention, even when the learned value stored in the second storage device disappears due to battery clearing or the like, the learned value can be restored and used continuously.

  According to the fourth invention, when a failure of the device related to the learning control is detected and the learning value stored in the first storage device is erased, the learning value is stored in the second storage device. The learning value is retained without being erased. Therefore, according to the present invention, the learning value for correcting the influence of the failure of the device is used during the period until the failure of the device is repaired, so that the learning control is performed so as to compensate for the influence of the failure more. Can do.

  Embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited to the following embodiments.

Embodiment 1 FIG.
[Configuration of Embodiment 1]
FIG. 1 is a diagram for explaining the configuration of an embodiment of the present invention. The vehicle control device of the present embodiment is a control device for controlling an internal combustion engine (engine) 2 mounted on a vehicle. As shown in FIG. 1, the internal combustion engine 2 includes an ECU (Electronic Control Unit) 10 as a control device. The ECU 10 comprehensively controls various devices related to the operation of the engine 2 based on engine operation data detected by a plurality of sensors. A plurality of actuators (not shown) are connected to the output side of the ECU 10. In addition, a plurality of sensors and devices (not shown) are connected to the input side of the ECU 10. The ECU 10 executes various controls of the engine 2 such as fuel injection control, ignition timing control, throttle control, and diagnosis based on input signals from these sensors. Hereinafter, the configuration of the ECU 10 will be described in detail.

  ECU10 of this Embodiment is provided with CPU12. The CPU 12 executes various processes for controlling the engine. The ECU 10 also includes a ROM 22 that stores a program executed by the CPU 12, and an NRAM 24 and an SRAM 26 as RAM for calculation work that temporarily stores control calculation results and the like by the CPU 12. The NRAM 24 is a memory that is not backed up by a battery voltage, and is a memory that loses stored data when the ignition is turned off. On the other hand, the SRAM 26 is a memory that is backed up by a battery voltage, and does not lose the stored data even when the ignition is turned off. Further, as shown in FIG. 1, the ECU 10 includes an EEPROM 28. The EEPROM 28 is a non-volatile memory in which data can be electrically rewritten, and can retain data even when power supply is interrupted.

  As shown in FIG. 1, the ECU 10 includes an input circuit 14 and an output circuit 16. The input circuit 14 inputs output signals of various sensors (not shown) such as a rotation speed sensor and a water temperature sensor to the CPU 12. The output circuit 16 operates various actuators (not shown) such as an injector and a relay based on a drive signal output from the CPU 12. The ECU 10 includes a power supply circuit 18. The power supply circuit 18 receives an ignition voltage supplied from a battery (not shown) via an ignition switch (not shown), outputs an operating voltage to the CPU 12, ROM 22, NRAM 24, SRAM 26, and EEPROM 28, and does not pass from the battery via the ignition switch. In response to the battery voltage directly supplied to the SRAM 26, a backup voltage for data retention is output to the SRAM 26.

[Operation in Embodiment 1]
Next, the operation of the present embodiment will be described. In the ECU 10 having the above-described configuration, engine control such as fuel injection control, ignition timing control, throttle control, and diagnosis is executed in accordance with a program stored in the ROM 22. More specifically, when the ignition switch is turned on, the operating voltage is output from the power supply circuit 18 to the CPU 12, ROM 22, NRAM 24, SRAM 26, and EEPROM 28. Engine control processing is executed in accordance with a program stored in the ROM 22, and various actuators are operated via the output circuit 16 based on signals from various sensors input to the input circuit 14.

  Here, in the control of the internal combustion engine 2 performed by the ECU 10, learning control for correcting a steady error component is performed. Specifically, a steady error component superimposed on a parameter related to engine control due to aging deterioration or individual difference of a sensor or actuator is learned and corrected based on a history of control results. The learning value is updated as needed each time a new value is calculated and stored in the NRAM 24. Here, as described above, the stored data is lost in the NRAM 24 when the ignition is turned off. Therefore, the learning value stored in the NRAM 24 is periodically written in the SRAM 26. As a result, the learning value can be held even when the ignition is turned off, so that the learning control can be continuously performed using the learning value when the ignition is turned on next time.

  However, when the backup voltage is interrupted by clearing the battery or the like, the learning value stored in the SRAM 26 is lost. Therefore, in the system according to the present embodiment, the learning value stored in the SRAM 26 is periodically written in the EEPROM 28. Specifically, when the learning value stored in the SRAM 26 is updated to a new value, the learning value is written into the EEPROM 28 when the subsequent ignition is turned off. Thereby, even if the learning value stored in the SRAM 26 is accidentally lost, the learning value can be restored by performing the operation of restoring the learning value stored in the EEPROM 28 to the SRAM 26.

[Characteristic operation of this embodiment]
Next, a characteristic operation of the present embodiment will be described. In the ECU 10, failure diagnosis control of devices such as sensors and actuators connected to the control device is performed. Specifically, the sensors detect failure, disconnection, short circuit, and the like by constantly monitoring and comparing input signals, for example. In addition, the actuators are subjected to failure diagnosis using a current limit value or the like. If a failure is detected, the user is promptly notified.

  Here, when a failure of a device is discovered by the above-described failure diagnosis control, if the failure has occurred suddenly, such as a disconnection, the learning is immediately prohibited after the failure is detected, so that the influence of the failure becomes a learned value. It is possible to prevent overlapping. However, for example, when the performance gradually declines due to aging of the device, and finally it is determined to be a failure, the influence of aging of the device is already superimposed on the learning value, Such learning values cannot be used after repair.

  Further, if the learning value is stored only in the SRAM 26, all the data stored in the SRAM 26 is lost when the battery is cleared in the repair work, and the learning value before repair is used after repair. Does not occur. However, when the learning value is backed up in the EEPROM as in the system of the present embodiment, the learning value stored is not lost even if the battery is cleared. May cause malfunction of the device due to incorrect learning control.

  Therefore, in the system of the present embodiment, when a failure is detected, the learning value stored in the EEPROM 28 is deleted. Thereby, in the engine control after repair, the situation where the learning value on which the influence of the failure is superimposed can be avoided.

  When the learning value in the EEPROM 28 is erased, the learning value stored in the SRAM 26 is held as it is. As a result, during the period from when a failure is detected to when it is repaired, learning control can be performed using a learning value that has been learned to compensate for the effects of the failure, effectively preventing malfunctions caused by the failure. Can be suppressed.

[Specific Processing in Embodiment 1]
Next, with reference to FIG. 2, the specific content of the process performed in this Embodiment is demonstrated. FIG. 2 is a flowchart of a routine in which the ECU 10 executes learning value writing or reading processing related to the control of the engine 2. First, a routine for learning value backup processing from the SRAM 26 to the EEPROM 28 will be described.

  In the routine shown in FIG. 2, it is first determined whether or not the ignition is turned on (step 100). Specifically, it is determined whether or not the ignition switch is turned on and the battery voltage is supplied to the ROM 22, NRAM 24, SRAM 26, and EEPROM 28.

  When it is determined in step 100 that the ignition is turned off, the process proceeds to the next step, and it is determined whether or not the learning value has been changed in the immediately preceding trip (step 102). Here, specifically, it is determined whether or not the learning value data stored in the SRAM 26 has been updated to new data in the previous trip. As a result, when it is determined that the learning value has been updated, the process proceeds to the next step, and the learning value data stored in the SRAM 26 is written into the EEPROM 28 (step 104). Next, a flag indicating that this routine is ignition off is turned on (step 106), and this routine is terminated. On the other hand, if it is determined in step 102 that the learning value data is not updated, it is determined that it is not necessary to update the learning value data stored in the EEPROM 28, and the processing in step 106 is executed. This routine is terminated later.

  According to the processing described above, the learning value updated in the immediately preceding trip can be written in the EEPROM 28. Thereby, the learning value data stored in the EEPROM 28 can always be kept up-to-date.

  Next, a learning value return processing routine from the EEPROM 28 to the SRAM 26 will be described. If it is determined in step 100 that the ignition is turned on, the process proceeds to the next step, and it is determined whether or not the routine is immediately after the ignition is turned on (step 108). Specifically, it is determined whether or not the flag in step 106 is ON. As a result, if the flag is on, it is determined that the routine is immediately after the ignition is turned on, the process proceeds to the next step, and the mirror check of the SRAM 26 is performed (step 110). Specifically, the data in the SRAM 26 at the end of the last trip and the current are compared, and it is determined whether or not the data in the SRAM 26 is lost due to battery clearing or the like.

  If it is determined in step 110 that the data in the SRAM 26 has been lost, the process proceeds to the next step, and the learning value data stored in the EEPROM 28 is written in the SRAM 26 (step 112). Next, the flag indicating that the routine is ignition off is turned off (step 114), and the routine is terminated. On the other hand, if it is determined in step 110 that the data in the SRAM 26 has not disappeared, it is determined that there is no need to rewrite the data in the SRAM 26 in particular, and this routine is immediately terminated.

  According to the process described above, when the battery is cleared during the period when the ignition is off and the learned value data stored in the SRAM 26 disappears, the learned value data stored in the EEPROM 28 is stored. It is returned to the SRAM 26. Thereby, the learning value before battery clear can be used continuously.

  Next, a learning value erasing process routine of the EEPROM 28 when a component failure is detected will be described. If it is determined in step 100 that the ignition is turned on, the process proceeds to step 108, and it is determined whether or not the routine is immediately after the ignition is turned on. As a result, when the flag is off, the process proceeds to the next step, and it is determined whether or not a failure of the device related to the learning control is detected (step 116). Specifically, it is determined whether or not a failure of these devices has been detected in the failure diagnosis control separately executed in the ECU 10.

  If it is determined in step 116 that a failure has been detected, the process proceeds to the next step, and the learning value erasure process of the EEPROM 28 is executed (step 118). Here, specifically, all the learning value data stored in the EEPROM 28 is erased. Then, after executing the processing of step 106, this routine is terminated. On the other hand, if it is determined in step 116 that no failure has been detected, it is determined that it is not necessary to delete the learning value data stored in the EEPROM 28, and after executing the processing of step 106, this routine is executed. Is terminated.

  According to the processing described above, when a failure is detected in a device related to learning control of the internal combustion engine 2, the learning value data stored in the EEPROM 28 is erased. The data stored in the EEPROM 28 is not lost simply by turning off the battery at the time of repair. For this reason, by deleting the learning value on which the influence of the failure is superimposed prior to the repair, it is possible to avoid a situation in which the learned value is used after the repair, and to prevent a malfunction.

  By the way, in Embodiment 1 described above, when a failure of a device related to learning control is detected, all the learning values stored in the EEPROM 28 are erased. However, the learning values to be erased are not limited to this. I can't. That is, only the learning value related to the control of the failed device may be specified and deleted from the learning value data stored in the EEPROM 28.

  In the first embodiment described above, the EEPROM 28 corresponds to the “first storage device” in the first aspect of the invention, and the ECU 10 executes the process of step 104 to execute the first step. The “learned value erasing means” according to the first aspect of the present invention is realized by the “learning value storage means” according to the invention executing the processing of step 116.

  In the first embodiment described above, the SRAM 26 corresponds to the “second storage device” in the third aspect of the invention, and the ECU 10 executes the process of step 112 above to execute the third step. The “learning value return means” in the invention is realized.

It is a figure for demonstrating the structure of ECU10 as a control apparatus of Embodiment 1 of this invention. It is a flowchart of the routine performed in Embodiment 1 of the present invention.

Explanation of symbols

2 Internal combustion engine
10 ECU (Electronic Control Unit)
12 CPU
14 Input circuit 16 Output circuit 18 Power supply circuit 22 ROM
24 NRAM
26 SRAM
28 EEPROM

Claims (4)

In a vehicle control apparatus that executes learning control for correcting an error component that is steadily included in a parameter related to vehicle control,
A first storage device capable of holding stored data even when power supply is interrupted;
Learning value storage means for storing the learning value calculated in the learning control in the first storage device;
A failure detection means for detecting a failure of the device related to the learning control;
When a failure of the device is detected by the failure detection means, learned value erasure means for erasing the learned value stored in the first storage device;
A vehicle control apparatus comprising:   The vehicle control device according to claim 1, wherein the first storage device is a nonvolatile memory capable of electrically rewriting data. The learning value storage means stores the learning value stored in the second storage device that loses the stored data when power supply is interrupted as a backup in the first storage device. And
Learning value return means for returning the learning value stored in the first storage device to the second storage device when the power supply to the second storage device is restored after being interrupted once. The vehicle control device according to claim 1, further comprising a vehicle control device.   4. The apparatus according to claim 3, further comprising learning value holding means for holding the learning value stored in the second storage device when a failure of the device is detected by the failure detecting means. Vehicle control device.

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