WO2021240895A1

WO2021240895A1 - Internal combustion engine control device

Info

Publication number: WO2021240895A1
Application number: PCT/JP2021/004260
Authority: WO
Inventors: 章広小森; 真也佐藤
Original assignee: 日立Astemo株式会社
Priority date: 2020-05-27
Filing date: 2021-02-05
Publication date: 2021-12-02
Also published as: JP7431960B2; JPWO2021240895A1; CN115485464A

Abstract

Provided is an internal combustion engine control device capable of correcting an error generated in estimating the remaining amount of particulate matter with respect to an appropriate estimation unit. The internal combustion engine control device comprises a control unit 400 that controls the regeneration operation of a filter. The control unit 400 comprises a deposit amount estimation unit 402, an incineration amount estimation unit 403, a remaining amount estimation unit 404, and an estimated error determination unit 408. The deposit amount estimation unit 402 estimates the amount of deposit. The incineration amount estimation unit 403 estimates the amount of incineration. The remaining amount estimation unit 404 estimates the remaining amount of particulate matter on the basis of the estimated amount of deposit and the estimated amount of incineration. Then, the estimated error determination unit 408 determines whether the error in the estimated remaining amount estimated by the remaining amount estimation unit 404 is an error due to the deposit amount estimation unit 402 or an error due to the incineration amount estimation unit 403, and performs correction with respect to the estimation unit determined.

Description

Internal combustion engine controller

The present invention relates to an internal combustion engine control device.

In an internal combustion engine, soot is generated as a particulate matter when the air-fuel mixture, which is a mixture of fuel and air, burns. In order to reduce the amount of soot emitted, the internal combustion engine is provided with a gasoline particulate filter (Gasoline Particulate Filter: hereinafter referred to as "GPF"), which is a filter for collecting soot. In order to prevent clogging, the GPF is subjected to a regeneration operation of burning and removing (incinerating) the collected soot when a predetermined amount of soot is accumulated.

FIG. 13 is a time chart showing an operation example of the conventional GPF reproduction control.
As shown in FIG. 13, when the temperature of the GPF reaches the renewable temperature or higher, oxygen is supplied to the GPF by the fuel cut (F / C) executed when the accelerator of the vehicle is decelerated. Then, the GPF is regenerated by burning the soot. When performing the GPF regeneration operation, the amount of soot deposited on the GPF before regeneration (soot accumulation amount), the amount of incinerated soot after the regeneration operation, and the estimation operation of the remaining soot remaining in the GPF. Is done.

Next, an outline of a conventional method for estimating the remaining amount of soot will be described with reference to FIGS. 14 to 16.
FIG. 14 is a schematic diagram showing a first method in the conventional method for estimating the remaining amount of soot.
In the first method shown in FIG. 14, the soot accumulation amount estimation logic for estimating the soot accumulation amount, the soot incineration amount estimation logic for estimating the soot incineration amount, and the soot remaining amount estimation logic for estimating the soot remaining amount are used. It is composed. In the soot accumulation amount estimation logic and the soot incineration amount estimation logic, the soot accumulation amount and the soot incineration amount are estimated from logical operations using physical formulas and MAPs. Then, in the soot remaining amount estimation logic, the soot remaining amount is estimated by subtracting the estimated soot incineration amount from the estimated soot accumulation amount.

15A to 15C are schematic views showing a second method in the conventional method for estimating the remaining amount of soot.
In the second method, as shown in FIG. 15A, the pressure difference (differential pressure) between the upstream side and the downstream side of the GPF is measured by using a differential pressure sensor. Then, as shown in FIG. 15C, the remaining soot is estimated from the calibration curve showing the relationship between the differential pressure ΔP shown in FIG. 15B and the remaining amount of soot.

As shown in FIG. 13, in the conventional method for estimating the remaining amount of soot, an error between the estimated value and the actual value occurs. Then, in order to eliminate this error, an estimated value correction process is performed.
FIG. 16 is a schematic diagram showing a third method in the conventional method for estimating the remaining amount of soot. The third method shown in FIG. 16 corrects the estimated value by combining the first method and the second method described above.

As shown in FIG. 16, in the third method, the second method, that is, the logic which is the first method using the remaining soot amount estimated by using the differential pressure ΔP of GPF as a reference value (true value). Calculate the difference from the remaining soot estimated by calculation. Then, the calculated difference is used to correct the soot accumulation amount estimation logic.

As a conventional technique for estimating the remaining amount of soot, for example, there is one described in Patent Document 1. In Patent Document 1, the first estimator based on the operating state of the internal combustion engine and the second estimator based on the differential pressure before and after the filter are calculated, and the deviation between the first estimator and the second estimator is calculated. A technique for calculating and correcting the soot deposit amount using this deviation is described.

FIGS. 17A to 18B are explanatory diagrams showing an error that occurs in the estimated value of the remaining soot amount by the logical operation. 17A and 17B show the error due to the soot deposit estimation logic, and FIGS. 18A and 18B show the error due to the soot incineration amount estimation logic.

In the examples shown in FIGS. 17A and 17B, when an error occurs in the soot accumulation amount estimation logic, an error occurs due to an excessive calculation of the estimated soot accumulation amount, so that an error occurs in the estimated soot remaining amount after regeneration. Occurs. At this time, the estimated remaining amount of soot calculated by the differential pressure is set as the true value, and the difference from the estimated remaining amount of soot calculated by the logical operation is calculated. Then, the estimation unit (soot accumulation amount estimation logic) for estimating the estimated soot accumulation amount is corrected by the calculated difference.

On the other hand, in the examples shown in FIGS. 18A and 18B, when an error occurs in the soot incineration amount estimation logic, an estimation error occurs due to an undercalculation of the estimated incineration amount, so that the estimated soot residue after reproduction occurs. There will be an error in the amount. At this time, the estimated remaining amount of soot calculated by the differential pressure is set as the true value, and the difference from the estimated remaining amount of soot calculated by the logical operation is calculated. Then, in the prior art, the calculated difference is an error due to the soot incineration amount, but the estimation unit (soot accumulation amount estimation logic) for calculating the estimated soot accumulation amount is corrected.

Japanese Unexamined Patent Publication No. 2019-105181

Further, the error caused in the estimated value of the remaining amount of soot by the logical operation includes not only the error caused by the estimated value of the accumulated soot amount as shown in FIGS. 17A and 17B, but also as shown in FIGS. 18A and 18B. , There is also an error due to the estimated value of soot incineration. However, in the technique described in Patent Document 1, when a difference occurs between the first estimated amount and the second estimated amount, the deviation is always corrected for the soot accumulation amount estimation unit. Therefore, the estimation unit that calculates the accurate estimated value will be corrected by the error caused by the estimation of the soot incineration amount, and an error will occur in the estimated soot accumulation amount at the next GPF regeneration operation. It was necessary to make corrections using the differential pressure sensor again.

An object of the present invention is to provide an internal combustion engine control device capable of correcting an error generated when estimating the remaining amount of particulate matter to an appropriate estimation unit in consideration of the above problems.

In order to solve the above problems and achieve the purpose, the internal combustion engine control device is provided with a control unit provided in the exhaust passage to control the regeneration operation of the filter that collects particulate matter in the exhaust gas. The control unit includes a deposit amount estimation unit, an incinerator amount estimation unit, a remaining amount estimation unit, and an estimation error determination unit. The deposit estimation unit estimates the deposit of particulate matter deposited on the filter. The incinerator amount estimation unit estimates the incinerator amount of the particulate matter to be incinerated during the regeneration operation. The remaining amount estimation unit estimates the remaining amount of particulate matter remaining in the filter based on the estimated accumulated amount estimated by the deposit amount estimation unit and the estimated incinerator amount estimated by the incinerator amount estimation unit. Then, the estimation error determination unit determines whether the error of the estimated remaining amount estimated by the remaining amount estimation unit is the error caused by the accumulated amount estimation unit or the incineration amount estimation unit, and determines whether the error is caused by the incineration amount estimation unit. Make corrections for it.

According to the internal combustion engine control device having the above configuration, it is possible to correct an error generated when estimating the remaining amount of particulate matter for an appropriate estimation unit.

It is a schematic block diagram which shows the structure of the internal combustion engine equipped with the internal combustion engine control device which concerns on embodiment. It is a block diagram which shows the control system of the internal combustion engine control device which concerns on embodiment. It is a block diagram which shows the GPF control apparatus of the internal combustion engine control apparatus which concerns on embodiment. It is a flowchart which shows the 1st operation example of the calculation operation of the estimated remaining amount of soot in the internal combustion engine control device which concerns on embodiment. It is a time chart which shows the 1st operation example of the calculation operation of the estimated soot remaining amount in the internal combustion engine control device which concerns on embodiment, and is the figure which shows just before the reproduction of GPF. It is a time chart which shows the 1st operation example of the calculation operation of the estimated soot remaining amount in the internal combustion engine control device which concerns on embodiment, and is the figure which shows right after the reproduction of GPF. It is explanatory drawing which shows the actual value and the estimated value of the soot accumulation amount with respect to the conventional example. It is explanatory drawing which shows the actual value and the estimated value of the soot accumulation amount in the internal combustion engine control device which concerns on embodiment. It is a flowchart which shows the 2nd operation example of the calculation operation of the estimated remaining amount of soot in the internal combustion engine control device which concerns on embodiment. It is a flowchart which shows the 2nd operation example of the calculation operation of the estimated remaining amount of soot in the internal combustion engine control device which concerns on embodiment. It is a time chart which shows the 2nd operation example of the calculation operation of the estimated soot remaining amount in the internal combustion engine control device which concerns on embodiment, and is the figure which shows just before the reproduction of GPF. It is a time chart which shows the 2nd operation example of the calculation operation of the estimated soot residual quantity in the internal combustion engine control device which concerns on embodiment, and is the figure which shows the state which the internal combustion engine stopped. It is a time chart which shows the operation example of the reproduction control of the conventional GPF. It is a schematic diagram which shows the 1st method in the conventional method of estimating the remaining amount of soot. A second method in the conventional method for estimating the remaining amount of soot is shown, and FIGS. 15A to 15C are schematic views showing the second method. It is a schematic diagram which shows the 3rd method in the conventional method of estimating the remaining amount of soot. FIG. 17A shows a case where there is no error, and FIG. 17B is an explanatory diagram showing an error caused by the soot accumulation amount estimation logic. FIG. 18A shows a case where there is no error, and FIG. 18B is an explanatory diagram showing an error caused by the soot incineration amount estimation logic.

Hereinafter, embodiments of the internal combustion engine control device will be described with reference to FIGS. 1 to 12.
The common members in each figure are designated by the same reference numerals.

1. 1. Embodiment 1-1. Configuration Example of Internal Combustion Engine Control First, a configuration example of the internal combustion engine control device according to the embodiment (hereinafter referred to as “this example”) will be described with reference to FIGS. 1 to 3.
FIG. 1 is a schematic configuration diagram showing a configuration example of an internal combustion engine equipped with an internal combustion engine control device.

The internal combustion engine 2 shown in FIG. 1 is an in-cylinder injection type engine. The internal combustion engine 2 is a four-cycle engine that repeats four strokes of an intake stroke, a compression stroke, a combustion (expansion) stroke, and an exhaust stroke. Further, the internal combustion engine 2 is, for example, a multi-cylinder engine including four cylinders (cylinders).
The number of cylinders of the internal combustion engine 2 is not limited to four, and may have six or eight or more cylinders.

The internal combustion engine 2 includes an air flow sensor 41 for measuring the intake air amount, a compressor 42 for supercharging the intake air, an intercooler 43 for cooling the supercharged intake air, and a throttle valve 44 for adjusting the gas to be sucked into the cylinder 45. And. A throttle sensor 59 for detecting the opening degree of the throttle valve 44 is provided in the vicinity of the throttle valve 44.

Further, the internal combustion engine 2 includes a spark plug 46 that supplies ignition energy to the cylinder 45 of each cylinder, a fuel injection device 49 that injects fuel into the cylinder 45 of each cylinder, and fuel and gas that have flowed into the cylinder 45. It includes a cylinder 50 that compresses the air-fuel mixture. Further, the internal combustion engine 2 includes an intake valve 47 for adjusting the air-fuel mixture flowing into the cylinder 45 and an exhaust valve 48 for exhausting the exhaust gas after combustion.

Further, the internal combustion engine 2 includes a crank angle sensor 51 that detects a signal of a signal rotor attached to the crank shaft 60, and a water temperature sensor 52 that measures the temperature of cooling water. Further, the internal combustion engine 2 includes a turbine 53 that transmits the kinetic energy of the exhaust gas to the compressor 42 via a shaft, and a three-way catalyst 54 that purifies harmful substances in the exhaust gas. An A / F sensor 55 for detecting the oxygen concentration contained in the exhaust gas is attached in the vicinity of the three-way catalyst 54.

Further, the internal combustion engine 2 includes a gasoline particulate filter (Gasoline Particulate Filter: hereinafter referred to as “GPF”) 56 provided downstream of the three-way catalyst 54. The GPF 56 collects particulate matter, soot, contained in the exhaust gas. The GPF 56 is formed of a porous body having fine pores on the wall surface. Then, the GPF 56 collects and deposits soot in the fine holes formed in the wall surface.

Further, a GPF temperature sensor 57 is provided on the upstream side of the GPF 56, that is, between the three-way catalyst 54 and the GPF 56. The GPF temperature sensor 57 measures the temperature of the GPF 56. If the temperature of the GPF 56 is equal to or higher than the renewable temperature, oxygen is supplied and soot is incinerated by fuel cutting (hereinafter referred to as F / C) to regenerate the GPF 56.

Further, the GPF 56 is provided with a differential pressure sensor 58. The differential pressure sensor 58 measures the pressure difference (differential pressure) between the upstream side and the downstream side of the GPF 56. The differential pressure sensor 58 and the GPF temperature sensor 57 are connected to the internal combustion engine control device 11 (see FIG. 2), and the measured differential pressure information and temperature information are output to the internal combustion engine control device 11.

[ECU configuration]
Next, the configuration of the internal combustion engine control device 11 that controls the internal combustion engine 2 will be described with reference to FIG.
FIG. 2 is a block diagram showing the configuration of the internal combustion engine control device 11.

As shown in FIG. 2, the internal combustion engine control device 11 includes an input circuit 301, an input / output port 302, a RAM (RandomAccessMemory) 303, a ROM (ReadOnlyMemory) 304, and a CPU (Central ProcessingUnit) 305. Has. Further, the internal combustion engine control device 11 includes an electronically controlled throttle valve drive circuit 306, a fuel injection device drive circuit 307, and an ignition output circuit 308.

The output of each sensor such as the throttle sensor 59, the airflow sensor 41, the crank angle sensor 51, the water temperature sensor 52, the A / F sensor 55, the GPF temperature sensor 57, and the differential pressure sensor 58 is input to the input circuit 301. The input circuit 301 performs signal processing such as noise removal on the input signal and sends it to the input / output port 302. The value input to the input port of the input / output port 302 is stored in the RAM 303.

The ROM 304 stores a control program that describes the contents of various arithmetic processes executed by the CPU 305, a MAP, a data table, and the like used for each process. The RAM 303 is provided with a storage area for storing the value input to the input port of the input / output port 302 and the value representing the operation amount of each actuator calculated according to the control program.
Further, a value representing the operation amount of each actuator stored in the RAM 303 is sent to the output port of the input / output port 302.

The drive signal that realizes the target opening degree of the throttle valve 44 set in the output port of the input / output port 302 is sent to the motor that drives the throttle valve 44 via the electronically controlled throttle valve drive circuit 306. The drive signal of the fuel injection device 49 is an ON / OFF signal that is ON when the valve is opened and OFF when the valve is closed. The drive signal of the fuel injection device 49 set in the output port of the input / output port 302 is amplified to sufficient energy to drive the fuel injection device 49 by the fuel injection device drive circuit 307, and is supplied to the fuel injection device 49. Will be done.

The operation signal for the spark plug 46 is an ON / OFF signal that is turned ON when the primary coil in the ignition output circuit 308 is flowing and is turned OFF when the primary coil is not flowing. The ignition timing of the spark plug 46 is a time when the operation signal for the spark plug 46 changes from ON to OFF. The operation signal for the spark plug 46 set in the output port of the input / output port 302 is amplified by the ignition output circuit 308 to a sufficient energy required for ignition and supplied to the spark plug 46.

Further, the CPU 305 is provided with a GPF control device 400 (see FIG. 3) showing an example of a filter control unit that controls reproduction of the GPF 56.

[Configuration of GPF control device]
Next, the configuration of the GPF control device 400 will be described with reference to FIG.
FIG. 3 is a block diagram showing the configuration of the GPF control device 400.

As shown in FIG. 3, the GPF control device 400 includes an input unit 401, a soot accumulation amount estimation unit 402, a soot incineration amount estimation unit 403, a soot residual amount estimation unit 404, and a differential pressure type soot residual amount estimation unit 405. And an estimation error calculation unit 406 and a reproduction control unit 407. Further, the GPF control device 400 includes an estimation error determination unit 408.

The input unit 401 acquires the differential pressure information measured by the differential pressure sensor 58 and the temperature information measured by the GPF temperature sensor 57 from the RAM 303. Further, the detection flag of the GPF reproduction process is input from the CPU 305 to the input unit 401. The CPU 305 detects or predicts in advance the execution of the reproduction operation of the GPF 56 based on the map data and the navigation information, and inputs the detection flag to the input unit 401.

The soot accumulation amount estimation unit 402, which indicates the accumulation amount estimation unit, is composed of a MAP or a physical formula. The soot accumulation amount estimation unit 402 inputs the GPF temperature, the water temperature, the F / C flag, the fuel injection amount, etc., which indicate the temperature of the GPF 56, from the input unit 401. Then, the soot accumulation amount estimation unit 402 calculates the estimated soot accumulation amount, which is the amount of soot deposited on the GPF 56, from the input GPF temperature, water temperature, F / C flag, fuel injection amount, and the like. The soot accumulation amount estimation unit 402 outputs the calculated estimated soot accumulation amount to the soot remaining amount estimation unit 404.

The soot incinerator amount estimation unit 403, which indicates the incinerator amount estimation unit, is composed of a MAP or a physical formula. Similar to the soot accumulation amount estimation unit 402, the soot incineration amount estimation unit 403 inputs the GPF temperature and water temperature indicating the temperature of the GPF 56, the F / C flag, the fuel injection amount, and the like from the input unit 401. Then, the soot incineration amount estimation unit 403 calculates the estimated soot incineration amount, which is the amount of soot incinerated during the regeneration process, from the input GPF temperature, water temperature, F / C flag, fuel injection amount, and the like. The soot incinerator amount estimation unit 403 outputs the calculated estimated soot incinerator amount to the soot remaining amount estimation unit 404.

The soot remaining amount estimation unit 404 indicating the remaining amount estimation unit uses the estimated soot accumulation amount calculated by the soot accumulation amount estimation unit 402 and the estimated soot incineration amount calculated by the soot incineration amount estimation unit 403. Ask for. Then, the soot remaining amount estimation unit 404 outputs the calculated estimated soot remaining amount to the estimation error calculation unit 406.
The estimated soot remaining amount X is calculated by the following equation 1.
[Equation 1]
Estimated soot remaining amount X = estimated soot accumulation amount-estimated soot incineration amount

The differential pressure type soot remaining amount estimation unit 405 indicating the differential pressure type remaining amount estimation unit acquires the differential pressure information from the input unit 401. Then, the differential pressure type soot residual amount estimation unit 405 calculates the differential pressure estimated soot residual amount Y, which is the amount of soot deposited on the GPF 56, based on the differential pressure information. The differential pressure type soot remaining amount estimation unit 405 outputs the produced differential pressure estimated soot remaining amount Y to the estimation error calculation unit 406.

The estimation error calculation unit 406 uses the differential pressure estimated soot residual quantity Y calculated by the differential pressure type soot residual quantity estimation unit 405 as a true value, and the difference D of the estimated soot residual quantity X calculated by the soot residual quantity estimation unit 404, that is, estimation. Calculate the error. Then, the estimation error calculation unit 406 outputs the calculated estimation error to the estimation error determination unit 408.

The estimation error determination unit 408 determines whether the estimation error acquired from the estimation error calculation unit 406 is an error due to the amount of soot accumulation or an error due to the amount of soot incineration. The estimation error determination unit 408 outputs an estimation error to the soot accumulation amount estimation unit 402 or the soot incineration amount estimation unit 403 based on the determination result, and corrects the soot accumulation amount estimation unit 402 or the soot incineration amount estimation unit 403. Then, the corrected soot accumulation amount estimation unit 402 and the soot incineration amount estimation unit 403 correct the soot accumulation amount and the estimated soot incineration amount, and output the corrected value to the soot remaining amount estimation unit 404.

Further, the soot remaining amount estimation unit 404 corrects the estimated soot remaining amount based on the corrected value and outputs it to the reproduction control unit 407. The reproduction control unit 407 is a reproduction command value related to the reproduction control based on the estimated remaining amount of soot (correction) calculated and corrected by the soot remaining amount estimation unit 404 and the GPF temperature input to the input unit 401. Is calculated. The regeneration command value is information on fuel cut permission and ignition retard.

The reproduction command value calculated by the reproduction control unit 407 is changed into a signal for the spark plug 46 and a drive signal of the fuel injection device 49 by the ignition timing control unit and the fuel injection control unit in the CPU 305, and the input / output port. It is set to 302 (see FIG. 3). Then, the set drive signal is output from the input / output port 302 to the fuel injection device drive circuit 307 and the ignition output circuit 308.

1-2. First Operation Example Next, a first operation example in the internal combustion engine control device 11 having the above-described configuration will be described with reference to FIGS. 4 to 6. In the first operation example, the calculation operation of the estimated remaining amount of soot will be described.
FIG. 4 is a flowchart showing an operation example of calculating the estimated remaining amount of soot. 5 and 6 are time charts showing the calculation operation of the estimated remaining soot amount, FIG. 5 is a diagram showing immediately before the reproduction of the GPF 56, and FIG. 6 is a diagram showing the immediately after the reproduction of the GPF 56.

As shown in FIG. 4, first, the CPU 305 detects the implementation of the F / C based on the map data and the navigation information while the vehicle is running (step S11). Then, as shown in FIG. 5, the CPU 305 measures the time t1 of the executed F / C. Next, the CPU 305 determines whether or not the time t1 of the executed F / C is a certain time or more (step S12). That is, the CPU 305 determines whether or not the reproduction operation of the GPF 56 has been performed for a certain period of time or longer.

When it is determined in the process of step S12 that the time t1 of the F / C is less than a certain time (NO determination in step S12), the CPU 305 ends the process. On the other hand, when it is determined in the process of step S12 that the time t1 of the F / C is equal to or longer than a certain time (YES determination in step S12), the GPF control device 400 deposits on the GPF 56 as shown in FIG. It is judged that all the soot has been incinerated.

Then, the soot accumulation amount estimation unit 402 considers that the soot accumulation amount of GPF56 is zero (step S13). That is, the soot accumulation amount estimation unit 402 calculates that the estimated soot accumulation amount is zero. As a result, the initial value of the soot accumulation amount is cleared to zero, that is, the reset process is performed. Further, in the process of step S13, the soot remaining amount estimation unit 404 also resets the estimated soot remaining amount to zero.

Further, when the reset process of the initial value is completed, the soot accumulation amount estimation unit 402 calculates the estimated soot accumulation amount from the information such as the GPF temperature, the water temperature, and the fuel injection amount. Then, the soot accumulation amount estimation unit 402 outputs the calculated estimated soot accumulation amount to the soot remaining amount estimation unit 404. Next, in the soot remaining amount estimation unit 404, the soot remaining amount of the GPF56 is accumulated in the period t2 (see FIG. 5) until the next regeneration operation occurs, that is, the period t2 until the next F / C is performed. It is estimated to be an amount (soot remaining amount = soot accumulation amount) (step S14). The soot remaining amount estimation unit 404 estimates that the estimated soot accumulation amount calculated by the soot accumulation amount estimation unit 402 is the soot remaining amount.

Next, the CPU 305 predicts whether or not F / C will occur based on the map data and navigation information, that is, the execution of the reproduction operation of the GPF 56 (step S15). When it is determined that F / C does not occur in the process of step S15 (NO determination in step S15), the CPU 305 ends the process.

On the other hand, when the CPU 305 determines that F / C will occur (YES determination in step S15), the CPU 305 inputs the detection flag to the input unit 401. When the detection flag is input, the input unit 401 acquires the differential pressure information ΔP (see FIG. 5) of the GPF 56 at t3 immediately before the start of the F / C from the differential pressure sensor 58, and makes a difference to the differential pressure type soot remaining amount estimation unit 405. The pressure information ΔP is input (step S16). Then, the differential pressure type soot remaining amount estimation unit 405 calculates the estimated soot remaining amount (differential pressure estimated soot remaining amount) Y by the differential pressure based on the differential pressure information ΔP acquired from the input unit 401.

Next, the estimation error calculation unit 406 determines whether there is an error between the estimated soot remaining amount Y by the differential pressure and the estimated soot remaining amount X by the logical operation (step S17). In the process of step S17, the estimation error calculation unit 406 acquires the estimated soot remaining amount Y calculated by the differential pressure type soot remaining amount estimation unit 405 as the estimated soot remaining amount Y due to the differential pressure. Further, the estimation error calculation unit 406 calculates the soot accumulation amount estimation unit 402 as the estimated soot residual amount X by logical operation, and acquires the estimated soot residual amount X estimated by the soot residual amount estimation unit 404. The estimation error calculation unit 406 obtains the difference between the estimated soot remaining amount Y and the estimated soot remaining amount X, and calculates the estimation error. Then, the estimation error calculation unit 406 determines, for example, whether or not there is an error based on whether or not the calculated estimation error exceeds the threshold value.

When the estimation error calculation unit 406 determines that there is no error in the process of step S17 (NO determination in step S17), the process proceeds to the process of step S19 described later.

Here, since the soot was never incinerated in the period t2 from the previous GPF56 regeneration operation to the current GPF56 regeneration operation, the estimation error calculated in t3 immediately before the regeneration is the soot accumulation amount estimation unit 402. It can be regarded as an error caused by. Therefore, when the estimation error calculation unit 406 determines that there is an error in the processing of step S17 (YES determination in step S17), the estimation error determination unit 408 determines that the estimation error calculated by the estimation error calculation unit 406 is the amount of soot deposited. It is determined that the error is caused by. Then, as shown in FIG. 5, the estimation error determination unit 408 corrects the soot accumulation amount estimation unit 402 (step S18).

By performing correction to the soot accumulation amount estimation unit 402, the soot accumulation amount estimation unit 402 corrects the estimated soot accumulation amount. Then, the soot accumulation amount estimation unit 402 outputs the corrected estimated soot accumulation amount to the soot remaining amount estimation unit 404. The soot remaining amount estimation unit 404 estimates that the corrected estimated soot accumulation amount is the soot remaining amount. Further, the soot remaining amount estimation unit 404 outputs the estimated soot remaining amount (correction) to the reproduction control unit 407.

Next, the CPU 305 determines whether or not the reproduction operation of the GPF 56 is completed (step S19). The CPU 305 determines, for example, that the reproduction operation of the GPF 56 is completed when the F / C execution flag is turned off. Alternatively, the CPU 305 estimates the time required for the F / C when estimating the implementation of the F / C in the process of step S15. Then, the CPU 305 determines that the reproduction operation of the GPF 56 is completed when the F / C time reaches the pre-estimated F / C time.

When it is determined in the process of step S19 that the reproduction operation of the GPF 56 is completed (YES determination in step S19), the CPU 305 inputs the detection flag to the input unit 401.
When the detection flag is input, the input unit 401 acquires t4 (see FIG. 6) immediately after the end of reproduction, that is, the differential pressure information ΔP (see FIG. 6) of the GPF 56 immediately after the end of F / C from the differential pressure sensor 58. The differential pressure information ΔP is input to the differential pressure type soot remaining amount estimation unit 405 (step S20). Then, the differential pressure type soot remaining amount estimation unit 405 calculates the estimated soot remaining amount (differential pressure estimated soot remaining amount) Y by the differential pressure based on the differential pressure information ΔP acquired from the input unit 401.

Further, during the regeneration operation of the GPF 56, that is, during the execution of the F / C, the soot incineration amount estimation unit 403 calculates the estimated soot incineration amount from the information such as the GPF temperature, the water temperature, and the fuel injection amount. Then, the soot incinerator amount estimation unit 403 outputs the calculated estimated soot incinerator amount to the soot remaining amount estimation unit 404. The soot remaining amount estimation unit 404 calculates the estimated soot remaining amount by differentiating the estimated soot incineration amount calculated by the soot incineration amount estimation unit 403 from the corrected soot accumulation amount.

Next, the estimation error calculation unit 406 determines whether there is an error between the estimated soot remaining amount Y by the differential pressure and the estimated soot remaining amount X by the logical operation (step S21). In the process of step S21, the estimation error calculation unit 406 acquires the estimated soot remaining amount Y calculated by the differential pressure type soot remaining amount estimation unit 405 as the estimated soot remaining amount Y due to the differential pressure. Further, the estimation error calculation unit 406 calculates the soot accumulation amount estimation unit 402 as the estimated soot residual amount X by logical operation, and acquires the estimated soot residual amount X estimated by the soot residual amount estimation unit 404. The estimation error calculation unit 406 obtains the difference between the estimated soot remaining amount Y and the estimated soot remaining amount X, and calculates the estimation error.

When the estimation error calculation unit 406 determines that there is no error in the process of step S21 (NO determination in step S21), the CPU 305 ends the process.

Here, since the soot accumulation amount has already been corrected, all the estimation errors calculated at t4 immediately after the end of regeneration can be regarded as errors caused by the soot incinerator amount estimation unit 403. Therefore, when the estimation error calculation unit 406 determines that there is an error in the processing of step S21 (YES determination in step S21), the estimation error determination unit 408 determines that the estimation error calculated by the estimation error calculation unit 406 is the amount of soot and incineration. It is determined that the error is caused by. Then, the estimation error determination unit 408 corrects the soot incinerator amount estimation unit 403 (step S22).

By making a correction to the soot incinerator amount estimation unit 403, the soot incinerator amount estimation unit 403 corrects the estimated soot incinerator amount. Then, the soot incinerator amount estimation unit 403 outputs the corrected estimated soot incinerator amount to the soot remaining amount estimation unit 404. The soot remaining amount estimation unit 404 estimates that the value obtained by subtracting the corrected estimated soot incineration amount from the corrected estimated soot accumulation amount is the soot remaining amount. Then, the soot remaining amount estimation unit 404 outputs the estimated soot remaining amount (correction) to the reproduction control unit 407. As a result, the calculation operation of the estimated remaining amount of soot in the internal combustion engine control device 11 is completed.

Further, when the estimation error calculation unit 406 determines that the estimation error is equal to or higher than a certain value in the processes of steps S17 and S21 described above, the estimation error calculation unit 406 determines that the differential pressure sensor 58 has failed. This makes it possible to determine the failure of the differential pressure sensor 58.
The value used for the failure determination is a value larger than the threshold value used for the presence or absence of an error.

As described above, according to the internal combustion engine control device 11 of this example, it is determined whether the estimation error is caused by the soot accumulation amount estimation unit 402 or the soot incineration amount estimation unit 403, respectively. The error can be corrected for the appropriate estimator.

Further, after the process of step S22, the estimated soot remaining amount (corrected) Z1 calculated by the soot remaining amount estimation unit 404 may be used as an initial value when the soot remaining amount is calculated next. That is, the next estimated soot remaining amount Z2 can be calculated by the estimated soot remaining amount (corrected) Z1 + the next estimated soot accumulation amount (corrected) W2-the next estimated soot incineration amount (corrected) W3. The soot accumulation amount estimation unit 402 stores the differential pressure information Q when calculating the estimated soot residual amount (corrected) Z1, and the differential pressure from the actual differential pressure when correcting the next estimated soot accumulation amount W2. Subtract information Q. As a result, the differential pressure of only the next estimated soot accumulation amount W2 can be obtained, and the next estimated soot accumulation amount W2 can be appropriately corrected.

1-3. Comparison with the conventional example Next, a comparison example of the actual value and the estimated value of the soot accumulation amount in the internal combustion engine control device 11 of the conventional example and this example will be described with reference to FIGS. 7 and 8.
7 and 8 show the actual value and the estimated value of the soot accumulation amount, FIG. 7 shows a conventional example, and FIG. 8 shows an example calculated by the internal combustion engine control device 11 of this example described above. Is shown.

In the conventional example shown in FIG. 7, as in the third method shown in FIG. 16, only in the soot accumulation amount estimation unit based on the error between the estimated soot residual value by the differential pressure and the estimated soot residual value by the logical operation. It has been corrected. That is, even if the error is caused by the soot incineration amount estimation unit, the soot accumulation amount estimation unit is corrected. Therefore, as shown in FIG. 7, an error due to the previous correction occurs in the soot accumulation amount estimation unit at the next regeneration operation. Then, the difference between the actual value and the estimated value of the soot accumulation amount becomes large. As a result, in the conventional example, in order to eliminate this difference, the number of corrections based on the differential pressure information of the differential pressure sensor has increased.

On the other hand, in the internal combustion engine control device 11 of this example, as described above, by determining whether the estimation error is caused by the soot accumulation amount estimation unit 402 or the soot incineration amount estimation unit 403. , Each error is corrected for the appropriate estimation part. That is, the error caused by the soot incineration amount estimation unit 403 is corrected not for the soot accumulation amount estimation unit 402 but for the soot incineration amount estimation unit 403.

Therefore, as shown in FIG. 8, an error due to the correction does not occur in the next reproduction operation, and the difference between the actual value and the estimated value of the soot accumulation amount can be reduced or eliminated. As a result, in the internal combustion engine control device 11 of this example, the number of corrections based on the differential pressure information of the differential pressure sensor 58 can be reduced as compared with the conventional example.

2. 2. Second Operation Example Next, a second operation example in the internal combustion engine control device 11 having the above-described configuration will be described with reference to FIGS. 9 to 12. In the first operation example, the calculation operation of the estimated remaining amount of soot will be described.
9 and 10 are flowcharts showing an example of calculation operation of the estimated remaining amount of soot. 11 and 12 are time charts showing the calculation operation of the estimated remaining soot amount, FIG. 11 is a diagram showing immediately before the reproduction of the GPF 56, and FIG. 12 is a diagram showing a state in which the internal combustion engine 2 is stopped.

The difference from the first operation example according to the second operation example is that it is determined that the internal combustion engine 2 is stopped by idling stop or the like before the reproduction operation of the GPF 56 is completed. As shown in FIGS. 9 and 11, the processing from step S31 to step S38 is the same as the processing from step S11 to step S18 in the first operation example, and thus the description thereof will be omitted.

As shown in FIG. 10, when the process of step S38 is completed, the CPU 305 determines whether or not the internal combustion engine 2 has stopped during the reproduction operation of the GPF 56 (step S41). When the CPU 305 determines that the internal combustion engine 2 has not stopped in the process of step S41 (NO determination in step S41), the process proceeds to the process of step S42. The processing from step S42 to step S45 is the same as the processing from step S19 to step S22 in the first operation example. Therefore, it is determined that the error generated during this period is an error caused by the soot incineration amount estimation unit 403, and the soot incineration amount estimation unit 403 is corrected.

On the other hand, as shown in FIG. 10, when the CPU 305 determines that the internal combustion engine 2 has stopped in the process of step S41 (YES determination in step S41), the differential pressure type soot remaining amount estimation unit 405 immediately after the stop. The differential pressure information ΔP (see FIG. 12) of the GPF 56 is recorded (step S46). Further, the soot remaining amount estimation unit 404 records the estimated soot remaining amount by the logical operation immediately after the stop (step S47). That is, the soot remaining amount estimation unit 404 records the value obtained by subtracting the estimated soot incineration amount calculated by the soot incineration amount estimation unit 403 immediately after the stop from the corrected estimated soot accumulation amount as the estimated soot remaining amount.

Next, as shown in FIG. 12, when the internal combustion engine 2 is restarted (step S48), the estimation error calculation unit 406 has an error in the estimated soot remaining amount Y by the differential pressure and the estimated soot remaining amount X by the logical operation. It is determined whether or not there is (step S49).

In the process of step S49, here, the differential pressure type soot remaining amount estimation unit 405 calculates and estimates the estimated soot remaining amount Y by the differential pressure using the differential pressure information recorded at t5 immediately after the internal combustion engine 2 is stopped. Output to the error calculation unit 406. Further, the soot remaining amount estimation unit 404 outputs the estimated soot remaining amount recorded in t5 immediately after the internal combustion engine 2 is stopped as the estimated soot remaining amount X by logical operation to the estimation error calculation unit 406. Then, the estimation error calculation unit 406 obtains the difference between the estimated soot remaining amount Y and the estimated soot remaining amount X, and the estimation error calculation unit 406 calculates the estimation error.

When the estimation error calculation unit 406 determines that there is no error in the processing of step S49 (NO determination in step S49), the CPU 305 ends the processing.

Here, since the soot accumulation amount has already been corrected, all the estimation errors calculated at t5 immediately after the internal combustion engine 2 is stopped can be regarded as errors caused by the soot incineration amount estimation unit 403. Therefore, when the estimation error calculation unit 406 determines that there is an error in the processing of step S49 (YES determination in step S49), the estimation error determination unit 408 determines that the estimation error calculated by the estimation error calculation unit 406 is the amount of soot and incineration. It is determined that the error is caused by. Then, the estimation error determination unit 408 corrects the soot incinerator amount estimation unit 403 (step S50).

Also in this second operation example, as in the first operation example, the error between the estimated remaining amount of soot due to the differential pressure and the estimated remaining amount of soot by the logical operation can be corrected for the appropriate estimation unit. Therefore, as shown in FIG. 8, an error due to the correction does not occur in the next reproduction operation, and the difference between the actual value and the estimated value of the soot accumulation amount can be reduced or eliminated, and the differential pressure sensor 58 can be compared with the conventional example. The number of corrections based on the differential pressure information can be reduced.

The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the gist of the invention described in the claims.

Further, an example of applying an in-cylinder injection type internal combustion engine that directly injects fuel into the combustion chamber of the cylinder 45 as an internal combustion engine has been described, but the present invention is not limited to this. For example, the fuel injection device 49 is arranged near the intake port in the intake pipe or near the throttle valve, and can be applied to an internal combustion engine that injects fuel into the intake pipe.

1 ... Vehicle, 2 ... Internal combustion engine, 11 ... Internal combustion engine control device, 45 ... Cylinder, 46 ... Spark plug, 47 ... Intake valve, 48 ... Exhaust valve, 49 ... Fuel injection device, 50 ... Piston, 54 ... Three-way catalyst , 56 ... GPF (gasoline party cute filter), 57 ... GPF temperature sensor, 58 ... differential pressure sensor, 301 ... input circuit, 302 ... input / output port, 303 ... RAM, 304 ... ROM, 305 ... CPU, 306 ... electronic control Throttle valve drive circuit, 307 ... Fuel injection device drive circuit, 308 ... Ignition output circuit 400 ... GPF control device (control unit), 401 ... Input unit, 402 ... Soot accumulation amount estimation unit (accumulation amount estimation unit), 403 ... Soot Incineration amount estimation unit (incineration amount estimation unit), 404 ... soot residual amount estimation unit (remaining amount estimation unit), 405 ... differential pressure type soot residual amount estimation unit (differential pressure type residual amount estimation unit), 406 ... estimation error calculation unit, 407 ... Playback control unit, 408 ... Estimated error judgment unit

Claims

It is equipped with a control unit that controls the regeneration operation of the filter that is installed in the exhaust passage and collects particulate matter in the exhaust.
The control unit
A deposit amount estimation unit that estimates the deposit amount of the particulate matter deposited on the filter, and a deposit amount estimation unit.
An incinerator amount estimation unit that estimates the incinerator amount of the particulate matter that is incinerated during the regeneration operation,
An remaining amount estimation unit that estimates the remaining amount of the particulate matter remaining in the filter based on the estimated accumulation amount estimated by the deposition amount estimation unit and the estimated incinerator amount estimated by the incinerator amount estimation unit.
It is determined whether the error of the estimated remaining amount estimated by the remaining amount estimation unit is the error caused by the accumulated amount estimation unit or the error caused by the incineration amount estimation unit, and the determined estimation unit is corrected. Estimation error judgment unit and
Internal combustion engine control device equipped with.
The control unit
A differential pressure type residual amount estimation unit that estimates the particulate matter remaining in the filter based on the differential pressure which is the difference between the pressures on the upstream side and the downstream side of the filter.
The first aspect of the present invention includes an estimation error calculation unit that calculates the error of the estimated remaining amount estimated by the remaining amount estimation unit from the estimated remaining amount due to the differential pressure estimated by the differential pressure type remaining amount estimation unit. Internal engine control device.
In the estimation error determination unit, the error of the estimated remaining amount estimated by the remaining amount estimation unit is the error from the time when the reproduction operation of the filter is performed for a certain period of time or more until the next reproduction operation of the filter is performed. The internal combustion engine control device according to claim 2, wherein it is determined that the error is caused by the deposit amount estimation unit.
When it is determined that the regeneration operation of the filter has been performed for a certain period of time or longer, the deposit amount estimation unit resets the initial value when the estimated deposit amount is zero.
The internal combustion engine control device according to claim 3, wherein the remaining amount estimation unit determines that the estimated remaining amount is the estimated accumulated amount until the regeneration operation of the filter is performed next.
In the estimation error determination unit, the error of the estimated remaining amount estimated by the remaining amount estimation unit is immediately after the reproduction operation of the filter is executed for a certain period of time or more and then the reproduction operation of the filter is executed. The internal combustion engine control device according to claim 4, wherein it is determined that the error is caused by the incineration amount estimation unit.
The internal combustion engine control device according to claim 1, wherein the deposit amount estimation unit and the incineration amount estimation unit calculate the estimated deposit amount and the estimated incineration amount from a MAP or a physical formula.
When the internal combustion engine is stopped after correcting the accumulated amount estimation unit, the differential pressure type remaining amount estimation unit records the differential pressure of the filter immediately after the stop, and the residual amount estimation unit immediately after the stoppage. The internal combustion engine control device according to claim 2, which records the calculated estimated remaining amount.
When the internal combustion engine is restarted, the differential pressure type remaining amount estimation unit estimates the estimated remaining amount immediately after the stop based on the differential pressure recorded immediately after the stop.
The internal combustion engine control device according to claim 7, wherein the estimation error calculation unit calculates an error of the estimated remaining amount recorded by the remaining amount estimation unit immediately after the stop from the estimated remaining amount immediately after the stop.
When the estimation error calculation unit determines that the error of the estimated remaining amount estimated by the remaining amount estimation unit is equal to or more than a certain value, it determines that the differential pressure sensor for measuring the differential pressure of the filter has failed. The internal combustion engine control device according to claim 2.
The internal combustion according to claim 1, wherein the remaining amount estimation unit sets the estimated remaining amount after correcting the accumulated amount estimation unit and the incineration amount estimation unit to the initial value when the estimated remaining amount is estimated next. Engine control device.