JP2019085948A - Control device of internal combustion engine - Google Patents
Control device of internal combustion engine Download PDFInfo
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- 238000002485 combustion reaction Methods 0.000 title claims abstract description 46
- 239000000446 fuel Substances 0.000 claims abstract description 89
- 238000002347 injection Methods 0.000 claims abstract description 42
- 239000007924 injection Substances 0.000 claims abstract description 42
- 238000000034 method Methods 0.000 claims description 14
- 238000000746 purification Methods 0.000 claims description 7
- 238000011946 reduction process Methods 0.000 claims 1
- 239000003054 catalyst Substances 0.000 abstract description 12
- 230000015556 catabolic process Effects 0.000 abstract 1
- 238000006731 degradation reaction Methods 0.000 abstract 1
- 239000000243 solution Substances 0.000 abstract 1
- 239000000203 mixture Substances 0.000 description 9
- 239000007789 gas Substances 0.000 description 8
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 4
- 231100000572 poisoning Toxicity 0.000 description 4
- 230000000607 poisoning effect Effects 0.000 description 4
- 229910052717 sulfur Inorganic materials 0.000 description 4
- 239000011593 sulfur Substances 0.000 description 4
- 238000011144 upstream manufacturing Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 238000011084 recovery Methods 0.000 description 2
- 240000002329 Inga feuillei Species 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Landscapes
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
本発明は、複数の気筒から排出された排気を浄化する排気浄化装置と、前記複数の気筒毎に設けられた燃料噴射弁と、を備える内燃機関を制御対象とする内燃機関の制御装置に関する。 The present invention relates to a control device for an internal combustion engine that controls an internal combustion engine including an exhaust gas purification device that purifies exhaust gas discharged from a plurality of cylinders, and a fuel injection valve provided for each of the plurality of cylinders.
たとえば特許文献１には、排気浄化触媒（排気浄化装置）の上流側の空燃比センサの検出値を目標値にフィードバック制御すべく、噴射量を補正する制御装置が記載されている。この制御装置は、排気浄化装置の昇温要求がある場合、一部の気筒における空燃比を理論空燃比よりもリッチとし、残りの気筒における空燃比を理論空燃比よりもリーンとするディザ制御処理を実行する。 For example, Patent Document 1 describes a control device that corrects the injection amount so as to feedback control the detected value of the air-fuel ratio sensor on the upstream side of the exhaust gas purification catalyst (exhaust gas purification device) to a target value. This control device performs dither control processing to make the air-fuel ratio in some of the cylinders richer than the theoretical air-fuel ratio and the air-fuel ratio in the remaining cylinders leaner than the stoichiometric air-fuel ratio when there is a temperature increase request of the exhaust purification device Run.
ところで、ディザ制御の実行時には、空燃比センサの検出値が、ディザ制御に起因して変動し、これによって空燃比の制御性が低下するおそれがある。 By the way, at the time of execution of the dither control, the detection value of the air-fuel ratio sensor fluctuates due to the dither control, which may lower the controllability of the air-fuel ratio.
上記課題を解決すべく、内燃機関の制御装置は、複数の気筒から排出された排気を浄化する排気浄化装置と、前記複数の気筒毎に設けられた燃料噴射弁と、を備える内燃機関を制御対象とし、前記複数の気筒のうちの一部の気筒を、空燃比が理論空燃比よりもリッチであるリッチ燃焼気筒とし、前記複数の気筒のうちの前記一部の気筒とは別の気筒を、空燃比が理論空燃比よりもリーンであるリーン燃焼気筒とすべく、前記燃料噴射弁を操作するディザ制御処理と、空燃比センサによって検出される空燃比を目標値にフィードバック制御すべく前記燃料噴射弁から噴射される噴射量を補正するフィードバック処理と、前記ディザ制御処理が実行されている場合、実行されていない場合よりも前記フィードバック処理のゲインを小さくする低減処理と、を実行する。 In order to solve the above problems, a control device for an internal combustion engine controls an internal combustion engine including an exhaust gas purification device for purifying exhaust gas discharged from a plurality of cylinders, and a fuel injection valve provided for each of the plurality of cylinders. The target is that some of the plurality of cylinders are rich combustion cylinders whose air fuel ratio is richer than the theoretical air fuel ratio, and cylinders other than the some cylinders of the plurality of cylinders are used. The dither control processing for operating the fuel injection valve and the fuel for performing feedback control of the air-fuel ratio detected by the air-fuel ratio sensor to a target value so as to obtain a lean combustion cylinder in which the air-fuel ratio is leaner than the stoichiometric air-fuel ratio Feedback processing for correcting the injection amount injected from the injection valve, and reduction when the gain of the feedback processing is made smaller when the dither control processing is performed than when it is not performed The execution and management, the.
上記構成では、ディザ制御処理が実行されている場合に実行されていない場合よりもフィードバック制御のゲインを小さくする。これにより、ディザ制御処理に起因して空燃比センサによって検出される空燃比がディザ制御処理を実行していない場合と比較して大きく変動する場合であっても、フィードバック制御の安定性が損なわれる事態に陥ることを抑制でき、ひいては空燃比の制御性の低下を抑制できる。 In the above configuration, the gain of feedback control is made smaller than in the case where dither control processing is being performed than in the case where it is not being performed. As a result, even if the air-fuel ratio detected by the air-fuel ratio sensor is largely fluctuated due to the dither control process as compared with the case where the dither control process is not performed, the stability of feedback control is impaired. It is possible to suppress the occurrence of a situation and, in turn, to suppress the decrease in the controllability of the air-fuel ratio.
以下、内燃機関の制御装置の一実施形態について、図面を参照しつつ説明する。
図１に示す内燃機関１０において、吸気通路１２から吸入された空気は、過給機１４を介して各気筒の燃焼室１６に流入する。燃焼室１６には、燃料を噴射する燃料噴射弁１８と、火花放電を生じさせる点火装置２０とが設けられている。燃焼室１６において、空気と燃料との混合気は、燃焼に供され、燃焼に供された混合気は、排気として、排気通路２２に排出される。排気通路２２のうちの過給機１４の下流には、酸素吸蔵能力を有した三元触媒２４が設けられている。
Hereinafter, an embodiment of a control device for an internal combustion engine will be described with reference to the drawings.
In the internal combustion engine 10 shown in FIG. 1, air taken in from the intake passage 12 flows into the combustion chamber 16 of each cylinder via the supercharger 14. The combustion chamber 16 is provided with a fuel injection valve 18 for injecting fuel and an igniter 20 for generating spark discharge. In the combustion chamber 16, the mixture of air and fuel is subjected to combustion, and the mixture supplied to combustion is discharged to the exhaust passage 22 as exhaust gas. A three-way catalyst 24 having an oxygen storage capacity is provided downstream of the turbocharger 14 in the exhaust passage 22.
制御装置３０は、内燃機関１０を制御対象とし、その制御量（トルク、排気成分等）を制御するために、燃料噴射弁１８や点火装置２０等の内燃機関１０の操作部を操作する。この際、制御装置３０は、三元触媒２４の上流側の空燃比センサ４０によって検出される空燃比Ａｆや、クランク角センサ４４の出力信号Ｓｃｒ、エアフローメータ４６によって検出される吸入空気量Ｇａを参照する。制御装置３０は、ＣＰＵ３２、ＲＯＭ３４、およびＲＡＭ３６を備えており、ＲＯＭ３４に記憶されたプログラムをＣＰＵ３２が実行することにより上記制御量の制御を実行する。 The control device 30 controls the internal combustion engine 10, and operates the operation part of the internal combustion engine 10 such as the fuel injection valve 18 and the ignition device 20 in order to control the control amount (torque, exhaust component, etc.). At this time, the controller 30 controls the air-fuel ratio Af detected by the air-fuel ratio sensor 40 upstream of the three-way catalyst 24, the output signal Scr of the crank angle sensor 44, and the intake air amount Ga detected by the air flow meter 46. refer. The control device 30 includes a CPU 32, a ROM 34, and a RAM 36. The CPU 32 executes a program stored in the ROM 34 to control the control amount.
図２に、制御装置３０が実行する処理の１つを示す。図２に示す処理は、ＲＯＭ３４に記憶されたプログラムをＣＰＵ３２がたとえば所定周期で繰り返し実行することにより実現される。なお、以下では、先頭に「Ｓ」が付与された数字によって、ステップ番号を表現する。 FIG. 2 shows one of the processes performed by the control device 30. The process shown in FIG. 2 is realized by the CPU 32 repeatedly executing the program stored in the ROM 34 at a predetermined cycle, for example. In the following, the step number is represented by a number to which "S" is added at the beginning.
図２に示す一連の処理において、ＣＰＵ３２は、クランク角センサ４４の出力信号Ｓｃｒに基づき算出された回転速度ＮＥと吸入空気量Ｇａとに基づきベース噴射量Ｑｂを算出する（Ｓ１０）。ベース噴射量Ｑｂは、燃焼室１６における混合気の空燃比を目標空燃比に開ループ制御するための操作量である開ループ操作量である。次にＣＰＵ３２は、ディザ制御時であるか否かを判定する（Ｓ１２）。そしてＣＰＵ３２は、ディザ制御時ではないと判定する場合（Ｓ１２：ＮＯ）、空燃比フィードバック制御の比例ゲインＫｐに、通常ゲインＫｐＨを代入する（Ｓ１４）。これに対し、ＣＰＵ３２は、ディザ制御時であると判定する場合（Ｓ１２：ＹＥＳ）、比例ゲインＫｐに、ディザ時ゲインＫｐＬを代入する（Ｓ１６）。ディザ時ゲインＫｐＬは、通常時ゲインＫｐＨよりも小さい値である。 In the series of processes shown in FIG. 2, the CPU 32 calculates the base injection amount Qb based on the rotational speed NE and the intake air amount Ga which are calculated based on the output signal Scr of the crank angle sensor 44 (S10). The base injection amount Qb is an open loop operation amount that is an operation amount for open loop control of the air fuel ratio of the air fuel mixture in the combustion chamber 16 to the target air fuel ratio. Next, the CPU 32 determines whether or not dither control is in progress (S12). When it is determined that the dither control is not being performed (S12: NO), the CPU 32 substitutes the normal gain KpH into the proportional gain Kp of the air-fuel ratio feedback control (S14). On the other hand, when it is determined that the dither control is being performed (S12: YES), the CPU 32 substitutes the dithering gain KpL for the proportional gain Kp (S16). The dithering gain KpL is a value smaller than the normal gain KpH.
ＣＰＵ３２は、Ｓ１４，Ｓ１６の処理が完了する場合、フィードバック制御量である空燃比Ａｆを目標値Ａｆ＊にフィードバック制御するための操作量であるフィードバック操作量ＫＡＦを算出する（Ｓ１８）。詳しくはＣＰＵ３２は、目標値Ａｆ＊と空燃比Ａｆとの差Δを入力とする比例要素、積分要素、および微分要素の各出力値の和を、ベース噴射量Ｑｂの補正比率δとし、フィードバック操作量ＫＡＦを、「１＋δ」とする。そして、ＣＰＵ３２は、ベース噴射量Ｑｂにフィードバック操作量ＫＡＦを乗算した値を、要求噴射量Ｑｄに代入する（Ｓ２０）。 When the processes of S14 and S16 are completed, the CPU 32 calculates a feedback operation amount KAF which is an operation amount for performing feedback control of the air-fuel ratio Af which is a feedback control amount to a target value Af * (S18). Specifically, the CPU 32 sets the sum of the output values of the proportional element, the integral element, and the differential element, which receives the difference Δ between the target value Af * and the air-fuel ratio Af, as the correction ratio δ of the base injection amount Qb. Let the quantity KAF be "1 + δ". Then, the CPU 32 substitutes a value obtained by multiplying the base injection amount Qb by the feedback operation amount KAF into the required injection amount Qd (S20).
次に、ＣＰＵ３２は、三元触媒２４の昇温要求があるか否かを判定する（Ｓ２２）。本実施形態では、三元触媒２４の暖機要求が生じていることと、硫黄被毒回復処理の実行要求が生じていることとの論理和が真である場合に、昇温要求があると判定する。ここで、三元触媒２４の暖機要求は、内燃機関１０の始動からの吸入空気量Ｇａの積算値ＩｎＧａが第１規定値Ｉｎｔｈ１以上である旨の条件（ア）と、積算値ＩｎＧａが第２規定値Ｉｎｔｈ２以下である旨の条件（イ）との論理積が真である場合に生じるものとする。ここで、第２規定値Ｉｎｔｈ２は、第１規定値Ｉｎｔｈ１よりも大きい。なお、条件（ア）は、三元触媒２４の上流側の端部の温度が活性温度となっていると判定される条件である。また、条件（イ）は、三元触媒２４の全体が未だ活性状態となっていないと判定される条件である。一方、硫黄被毒回復処理の実行要求は、硫黄被毒量が所定量以上となる場合に生じるものとする。ここで、ＣＰＵ３２は、図２とは別の処理で、要求噴射量Ｑｄの積算値に基づき硫黄被毒量を算出する。 Next, the CPU 32 determines whether there is a temperature increase request for the three-way catalyst 24 (S22). In the present embodiment, if the logical sum of the requirement for warm-up of the three-way catalyst 24 and the requirement for execution of the sulfur poisoning recovery processing is true, the requirement for temperature increase is present. judge. Here, the warm-up requirement of the three-way catalyst 24 is the condition (i) that the integrated value InGa of the intake air amount Ga from the start of the internal combustion engine 10 is greater than or equal to the first specified value Inth1; (2) It occurs when the logical product with the condition (i) that the specified value Inth2 or less is true is true. Here, the second predetermined value Inth2 is larger than the first predetermined value Inth1. Condition (a) is a condition determined that the temperature of the upstream end of the three-way catalyst 24 is the activation temperature. Condition (i) is a condition under which it is determined that the entire three-way catalyst 24 has not yet been activated. On the other hand, the execution request of the sulfur poisoning recovery process is generated when the sulfur poisoning amount is equal to or more than a predetermined amount. Here, the CPU 32 calculates the sulfur poisoning amount based on the integrated value of the required injection amount Qd in a process different from that of FIG.
ＣＰＵ３２は、昇温要求がないと判定する場合（Ｓ２２：ＮＯ）、噴射量指令値Ｑ＊に要求噴射量Ｑｄを代入する（Ｓ２４）。そしてＣＰＵ３２は、燃料噴射弁１８から噴射量指令値Ｑ＊に応じた量の燃料を噴射すべく、燃料噴射弁１８に操作信号ＭＳ２を出力する（Ｓ２６）。 When determining that there is no temperature increase request (S22: NO), the CPU 32 substitutes the required injection amount Qd into the injection amount command value Q * (S24). Then, the CPU 32 outputs an operation signal MS2 to the fuel injection valve 18 in order to inject fuel of an amount according to the injection amount command value Q * from the fuel injection valve 18 (S26).
これに対し、ＣＰＵ３２は、昇温要求があると判定する場合（Ｓ２２：ＹＥＳ）、要求噴射量Ｑｄの補正要求値（噴射量補正要求値α）を算出して出力する（Ｓ２８）。噴射量補正要求値αは、内燃機関１０の気筒＃１〜＃４のそれぞれから排出される排気全体の成分を、気筒＃１〜＃４の全てで燃焼対象とする混合気の空燃比を目標空燃比とした場合と同等としつつも、燃焼対象とする混合気の空燃比を気筒間で異ならせるディザ制御によって要求される要求噴射量Ｑｄの補正量である。ここで、本実施形態にかかるディザ制御では、第１の気筒＃１〜第４の気筒＃４のうちの１つの気筒を、混合気の空燃比を理論空燃比よりもリッチとするリッチ燃焼気筒とし、残りの３つの気筒を、混合気の空燃比を理論空燃比よりもリーンとするリーン燃焼気筒とする。そして、リッチ燃焼気筒における噴射量を、上記要求噴射量Ｑｄの「１＋α」倍とし、リーン燃焼気筒における噴射量を、要求噴射量Ｑｄの「１−（α／３）」倍とする。リーン燃焼気筒とリッチ燃焼気筒との上記噴射量の設定によれば、気筒＃１〜＃４のそれぞれに充填される空気量が同一であるなら、内燃機関１０の各気筒＃１〜＃４から排出される排気全体の成分を、気筒＃１〜＃４の全てで燃焼対象とする混合気の空燃比を目標空燃比とした場合と同等とすることができる。なお、上記噴射量の設定によれば、気筒＃１〜＃４のそれぞれに充填される空気量が同一であるなら、各気筒において燃焼対象とされる混合気の燃空比の平均値の逆数が目標空燃比となる。なお、燃空比とは、空燃比の逆数のことである。 On the other hand, when determining that there is a temperature increase request (S22: YES), the CPU 32 calculates and outputs a correction request value (injection amount correction request value α) of the request injection amount Qd (S28). The injection amount correction request value α targets the air-fuel ratio of the air-fuel mixture that is to be burned in all the cylinders # 1 to # 4 with the components of the entire exhaust discharged from each of the cylinders # 1 to # 4 of the internal combustion engine 10 This is the correction amount of the required injection amount Qd required by the dither control in which the air-fuel ratio of the mixture to be burned is made different among the cylinders while being made equal to the air-fuel ratio. Here, in the dither control according to the present embodiment, a rich combustion cylinder in which one of the first cylinder # 1 to the fourth cylinder # 4 is made richer in air-fuel ratio of air-fuel mixture than stoichiometric air-fuel ratio Let the remaining three cylinders be lean-burning cylinders in which the air-fuel ratio of the mixture is leaner than the stoichiometric air-fuel ratio. Then, the injection amount in the rich combustion cylinder is made “1 + α” times the required injection amount Qd, and the injection amount in the lean combustion cylinder is made “1− (α / 3)” times the required injection amount Qd. According to the setting of the injection amount of the lean combustion cylinder and the rich combustion cylinder, if the amount of air charged in each of the cylinders # 1 to # 4 is the same, from each cylinder # 1 to # 4 of the internal combustion engine 10 The component of the entire exhaust gas to be discharged can be made equal to the case where the air-fuel ratio of the mixture to be burned in all the cylinders # 1 to # 4 is made the target air-fuel ratio. Note that according to the setting of the injection amount, if the amount of air charged in each of the cylinders # 1 to # 4 is the same, the reciprocal of the average value of the fuel / air ratio of the mixture to be burned in each cylinder Becomes the target air-fuel ratio. The fuel-air ratio is the reciprocal of the air-fuel ratio.
詳しくは、ＣＰＵ３２は、内燃機関１０の動作点を規定する回転速度ＮＥおよび負荷率ＫＬに基づき、噴射量補正要求値αを可変設定する。ここで、負荷率ＫＬは、燃焼室１６内に充填される空気量を示すパラメータであり、ＣＰＵ３２により、吸入空気量Ｇａに基づき算出される。負荷率ＫＬは、基準流入空気量に対する、１気筒の１燃焼サイクル当たりの流入空気量の比である。ちなみに、基準流入空気量は、回転速度ＮＥに応じて可変設定される量としてもよい。 Specifically, the CPU 32 variably sets the injection amount correction request value α based on the rotational speed NE and the load factor KL that define the operating point of the internal combustion engine 10. Here, the load factor KL is a parameter indicating the amount of air charged into the combustion chamber 16, and is calculated by the CPU 32 based on the amount of intake air Ga. The load factor KL is a ratio of the amount of inflowing air per one combustion cycle of one cylinder to the reference amount of inflowing air. Incidentally, the reference inflow air amount may be an amount variably set according to the rotational speed NE.
そして、ＣＰＵ３２は、燃料噴射の対象となる気筒がリッチ燃焼気筒であるか否かを判定する（Ｓ３０）。ＣＰＵ３２は、リッチ燃焼気筒であると判定する場合（Ｓ３０：ＹＥＳ）、噴射量指令値Ｑ＊に、「Ｑｄ・（１＋α）」を代入し（Ｓ３２）、Ｓ２６の処理に移行する。これに対し、ＣＰＵ３２は、リーン燃焼気筒であると判定する場合（Ｓ３０：ＮＯ）、噴射量指令値Ｑ＊に、「Ｑｄ・｛１−（α／３）｝」を代入し（Ｓ３４）、Ｓ２６の処理に移行する。 Then, the CPU 32 determines whether the cylinder targeted for fuel injection is a rich combustion cylinder (S30). When determining that the cylinder is a rich combustion cylinder (S30: YES), the CPU 32 substitutes “Qd · (1 + α)” for the injection amount command value Q * (S32), and shifts to the processing of S26. On the other hand, when determining that the cylinder is a lean combustion cylinder (S30: NO), the CPU 32 substitutes “Qd · {1- (α / 3)}” for the injection amount command value Q * (S34), It shifts to the processing of S26.
なお、ＣＰＵ３２は、Ｓ２６の処理が完了する場合には、図２に示す一連の処理を一旦終了する。
以下、本実施形態の作用および効果について説明する。
When the process of S26 is completed, the CPU 32 temporarily ends the series of processes shown in FIG.
Hereinafter, the operation and effect of the present embodiment will be described.
ＣＰＵ３２は、三元触媒２４の昇温要求が生じると、ディザ制御を実行する。この場合、リッチ燃焼気筒の排気成分とリーン燃焼気筒の排気成分とが異なることから、空燃比センサ４０によって検出される空燃比Ａｆが、ディザ制御を実行していない場合よりも大きく変動することがある。そしてその場合、回転速度ＮＥなどが変化した際、空燃比フィードバック制御の制御周期と、ディザに起因した空燃比Ａｆの変動等が干渉し、フィードバック制御が共振、発散に陥り、空燃比制御の制御性が低下するおそれがある。そこで、本実施形態では、ディザ制御を実行する場合、フィードバック制御の比例ゲインＫｐを、ディザ制御が実行されていない場合よりも小さい値とする。これにより、比例ゲインＫｐを小さくしない場合と比較して、フィードバック制御が発散しにくくなることから、空燃比制御の制御性の低下を抑制できる。 The CPU 32 executes dither control when a temperature increase request for the three-way catalyst 24 occurs. In this case, since the exhaust component of the rich combustion cylinder and the exhaust component of the lean combustion cylinder are different, the air-fuel ratio Af detected by the air-fuel ratio sensor 40 fluctuates more than when dither control is not performed. is there. In that case, when the rotational speed NE or the like changes, the control period of the air-fuel ratio feedback control interferes with the fluctuation of the air-fuel ratio Af caused by the dither, and the feedback control falls into resonance and divergence, and the control of the air-fuel ratio control There is a risk that the sex may decline. Therefore, in the present embodiment, when performing dither control, the proportional gain Kp of feedback control is set to a smaller value than when dither control is not performed. As a result, compared to the case where the proportional gain Kp is not reduced, the feedback control is less likely to diverge, so that it is possible to suppress the decrease in the controllability of the air-fuel ratio control.
ちなみに、上記実施形態では、空燃比センサ４０を、気筒＃１〜＃４のそれぞれが排出する排気が合流した部分の排気成分を感知するものとしたが、これに代えて、合流した部分よりも上流側において、気筒毎にその排出した排気成分を感知する空燃比センサを設けることも考えられる。この場合、それぞれの空燃比センサが検出する空燃比をその気筒の目標値にフィードバック制御するなら、フィードバック制御が共振、発散に陥ることを抑制することが可能となる。ただしその場合、制御が煩雑となる。 Incidentally, in the above embodiment, the air-fuel ratio sensor 40 senses the exhaust component of the portion where the exhausts discharged from each of the cylinders # 1 to # 4 merge, but instead of this, it is better than the merged portion On the upstream side, it is also conceivable to provide an air-fuel ratio sensor that senses the exhausted exhaust component for each cylinder. In this case, if the air-fuel ratio detected by each air-fuel ratio sensor is feedback-controlled to the target value of the cylinder, it is possible to suppress feedback control from falling into resonance and divergence. However, in that case, control becomes complicated.
＜対応関係＞
上記実施形態における事項と、上記「課題を解決するための手段」の欄に記載した事項との対応関係は、次の通りである。排気浄化装置は、三元触媒２４に対応し、ディザ制御処理は、Ｓ２６〜Ｓ３４の処理に対応し、フィードバック処理は、Ｓ１８，Ｓ２０の処理に対応し、低減処理は、Ｓ１２〜Ｓ１６の処理に対応する。
<Correspondence relationship>
Correspondence between the matters in the above-mentioned embodiment and the matters described in the above-mentioned "means for solving the problem" is as follows. The exhaust purification device corresponds to the three-way catalyst 24, the dither control processing corresponds to the processing of S26 to S34, the feedback processing corresponds to the processing of S18 and S20, and the reduction processing corresponds to the processing of S12 to S16. It corresponds.
＜その他の実施形態＞
本実施形態は、以下のように変更して実施することができる。本実施形態および以下の変更例は、技術的に矛盾しない範囲で互いに組み合わせて実施することができる。
<Other Embodiments>
The present embodiment can be modified as follows. The present embodiment and the following modifications can be implemented in combination with one another as long as there is no technical contradiction.
・上記実施形態は、ディザ制御が実行される場合に実行されない場合と比較して、比例ゲインＫｐを小さい値としたが、これに限らない。たとえば比例ゲインＫｐに加えて、積分ゲインＫｉを小さい値としてもよく、またたとえば、比例ゲインＫｐに加えて微分ゲインＫｄを小さい値としてもよく、さらにたとえば、比例ゲインＫｐに加えて積分ゲインＫｉおよび微分ゲインＫｄを小さい値としてもよい。また、比例ゲインＫｐを小さい値とすることも必須ではなく、たとえば積分ゲインＫｉのみを小さい値としたり、微分ゲインＫｄのみを小さい値としたりしてもよい。なお、補正比率δを、比例要素、積分要素および微分要素の各出力値の和とすることも必須ではなく、たとえば比例要素および積分要素の出力値の和であってもよく、またたとえば比例要素および微分要素の和であってもよく、またたとえば比例要素の出力値としてもよい。また、たとえば積分要素および微分要素の和であってもよい。 In the above embodiment, although the proportional gain Kp is set to a smaller value as compared with the case where it is not performed when the dither control is performed, the present invention is not limited to this. For example, integral gain Ki may be a small value in addition to proportional gain Kp, and for example, derivative gain Kd may be a small value in addition to proportional gain Kp, and for example, integral gain Ki in addition to proportional gain Kp. The derivative gain Kd may be a small value. Further, it is not essential to set the proportional gain Kp to a small value. For example, only the integral gain Ki may be set to a small value, or only the derivative gain Kd may be set to a small value. The correction ratio δ may not be the sum of the output values of the proportional element, the integral element and the differential element, but may be, for example, the sum of the output values of the proportional element and the integral element. And the sum of differential elements, and may be, for example, output values of proportional elements. Also, it may be, for example, the sum of an integral element and a differential element.
・上記実施形態では、空燃比センサ４０によって検出される空燃比Ａｆが、空燃比センサ４０の出力値自体であるのか否かについて、特に記載しなかったが、たとえば出力値にローパスフィルタ処理を施した値を空燃比Ａｆとしてもよい。これは、たとえば、今回の出力値ＡＯＵＴ（ｎ）、前回の空燃比Ａｆ（ｎ−１）、および「１」よりも大きい数Ｎを用いて、今回の空燃比Ａｆ（ｎ）を、前回の空燃比Ａｆ（ｎ−１）に、「｛ＡＯＵＴ（ｎ）−Ａｆ（ｎ−１）｝／Ｎ」を加算した値とすることにより実現できる。この場合であっても、たとえば気筒毎の空燃比の変動をある程度は検知可能な時定数を設定する場合には、空燃比Ａｆがディザ制御に起因して変動するために、フィードバック制御が不安定となるおそれがあるため、フィードバック処理のゲインを小さくすることが有効である。また、噴射量補正要求値αを大きくするほど、ローパスフィルタ処理によって空燃比Ａｆからディザ制御による変動を除きにくくなるため、噴射量補正要求値αが大きい場合にもフィードバック制御が不安定となるおそれがあるため、フィードバック処理のゲインを小さくすることが有効である。 In the above embodiment, whether or not the air-fuel ratio Af detected by the air-fuel ratio sensor 40 is the output value of the air-fuel ratio sensor 40 is not particularly described. However, for example, the output value is subjected to low-pass filter processing. Alternatively, the air-fuel ratio Af may be set as the calculated value. For example, using the current output value AOUT (n), the previous air-fuel ratio Af (n−1), and the number N larger than “1”, the current air-fuel ratio Af (n) This can be realized by setting the value obtained by adding “{AOUT (n) −Af (n−1)} / N” to the air-fuel ratio Af (n−1). Even in this case, for example, when setting a time constant capable of detecting the fluctuation of the air-fuel ratio for each cylinder to some extent, the feedback control becomes unstable because the air-fuel ratio Af fluctuates due to the dither control. Therefore, it is effective to reduce the gain of feedback processing. Further, as the injection amount correction request value α becomes larger, it becomes more difficult to remove the fluctuation due to the dither control from the air-fuel ratio Af by low-pass filter processing, so feedback control may become unstable even when the injection amount correction request value α is large. Therefore, it is effective to reduce the gain of feedback processing.
・内燃機関としては、４気筒の内燃機関に限らない。また、燃料噴射弁としては、燃焼室１６に燃料を噴射するものに限らず、吸気通路１２に燃料を噴射するものであってもよい。 The internal combustion engine is not limited to a four-cylinder internal combustion engine. Further, the fuel injection valve is not limited to one injecting fuel into the combustion chamber 16, but may be one injecting fuel into the intake passage 12.
１０…内燃機関、１２…吸気通路、１４…過給機、１６…燃焼室、１８…燃料噴射弁、２０…点火装置、２２…排気通路、２４…三元触媒、３０…制御装置、３２…ＣＰＵ、３４…ＲＯＭ、３６…ＲＡＭ、４０…空燃比センサ、４４…クランク角センサ、４６…エアフローメータ。 DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 12 ... Intake passage, 14 ... Turbocharger, 16 ... Combustion chamber, 18 ... Fuel injection valve, 20 ... Ignition device, 22 ... Exhaust passage, 24 ... Three-way catalyst, 30 ... Control device, 32 ... CPU, 34: ROM, 36: RAM, 40: Air-fuel ratio sensor, 44: Crank angle sensor, 46: Air flow meter.
Claims (1)
前記複数の気筒のうちの一部の気筒を、空燃比が理論空燃比よりもリッチであるリッチ燃焼気筒とし、前記複数の気筒のうちの前記一部の気筒とは別の気筒を、空燃比が理論空燃比よりもリーンであるリーン燃焼気筒とすべく、前記燃料噴射弁を操作するディザ制御処理と、
空燃比センサによって検出される空燃比を目標値にフィードバック制御すべく前記燃料噴射弁から噴射される噴射量を補正するフィードバック処理と、
前記ディザ制御処理が実行されている場合、実行されていない場合よりも前記フィードバック処理のゲインを小さくする低減処理と、を実行する内燃機関の制御装置。 An internal combustion engine including an exhaust gas purification device for purifying exhaust gas discharged from a plurality of cylinders, and a fuel injection valve provided for each of the plurality of cylinders as a control target,
A part of the plurality of cylinders is a rich combustion cylinder whose air-fuel ratio is richer than the stoichiometric air-fuel ratio, and a cylinder other than the part of the plurality of cylinders is an air-fuel ratio Dither control processing for operating the fuel injection valve so as to make the lean combustion cylinder leaner than the stoichiometric air fuel ratio;
Feedback processing for correcting the injection amount injected from the fuel injection valve in order to feedback control the air-fuel ratio detected by the air-fuel ratio sensor to a target value;
A control device for an internal combustion engine, which executes a reduction process to make the gain of the feedback process smaller when the dither control process is performed than when the dither control process is not performed.
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Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0533705A (en) * | 1991-07-31 | 1993-02-09 | Nippondenso Co Ltd | Control apparatus for internal combustion engine |
| JPH06229308A (en) * | 1993-01-29 | 1994-08-16 | Mazda Motor Corp | Air-fuel ratio controller of engine |
| JPH07166934A (en) * | 1993-12-14 | 1995-06-27 | Mazda Motor Corp | Air fuel ratio controller of engine |
| JPH09222010A (en) * | 1996-02-15 | 1997-08-26 | Nissan Motor Co Ltd | Exhaust gas purifying device for engine |
| JP2001271691A (en) * | 2000-03-27 | 2001-10-05 | Mazda Motor Corp | Exhaust emission control device for engine |
| JP2002256934A (en) * | 2001-02-27 | 2002-09-11 | Mazda Motor Corp | Exhaust emission control device of engine |
| US6651422B1 (en) * | 1998-08-24 | 2003-11-25 | Legare Joseph E. | Catalyst efficiency detection and heating method using cyclic fuel control |
| JP2004076668A (en) * | 2002-08-20 | 2004-03-11 | Toyota Motor Corp | Control unit for internal combustion engine |
| JP2004092513A (en) * | 2002-08-30 | 2004-03-25 | Toyota Motor Corp | Combustion control device for internal combustion engine |
| KR20040046822A (en) * | 2002-11-28 | 2004-06-05 | 현대자동차주식회사 | A method for air fuel raio control of go with sustenance on vehicle |
| JP2008095542A (en) * | 2006-10-06 | 2008-04-24 | Toyota Motor Corp | Control system of internal combustion engine |
| JP2009002170A (en) * | 2007-06-19 | 2009-01-08 | Toyota Motor Corp | Air-fuel ratio control device for internal combustion engine |
| JP2012087673A (en) * | 2010-10-19 | 2012-05-10 | Toyota Motor Corp | Control device of internal combustion engine |
| US20160265467A1 (en) * | 2015-03-12 | 2016-09-15 | Toyota Jidosha Kabushiki Kaisha | Exhaust purification system of internal combustion engine |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6229308B2 (en) | 2013-05-23 | 2017-11-15 | 住友電気工業株式会社 | Regeneration rate estimation device, route search system, and computer program |
| JP7166934B2 (en) | 2017-02-03 | 2022-11-08 | 株式会社半導体エネルギー研究所 | semiconductor equipment |
-
2017
- 2017-11-08 JP JP2017215925A patent/JP7196391B2/en active Active
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0533705A (en) * | 1991-07-31 | 1993-02-09 | Nippondenso Co Ltd | Control apparatus for internal combustion engine |
| JPH06229308A (en) * | 1993-01-29 | 1994-08-16 | Mazda Motor Corp | Air-fuel ratio controller of engine |
| JPH07166934A (en) * | 1993-12-14 | 1995-06-27 | Mazda Motor Corp | Air fuel ratio controller of engine |
| JPH09222010A (en) * | 1996-02-15 | 1997-08-26 | Nissan Motor Co Ltd | Exhaust gas purifying device for engine |
| US6651422B1 (en) * | 1998-08-24 | 2003-11-25 | Legare Joseph E. | Catalyst efficiency detection and heating method using cyclic fuel control |
| JP2001271691A (en) * | 2000-03-27 | 2001-10-05 | Mazda Motor Corp | Exhaust emission control device for engine |
| JP2002256934A (en) * | 2001-02-27 | 2002-09-11 | Mazda Motor Corp | Exhaust emission control device of engine |
| JP2004076668A (en) * | 2002-08-20 | 2004-03-11 | Toyota Motor Corp | Control unit for internal combustion engine |
| JP2004092513A (en) * | 2002-08-30 | 2004-03-25 | Toyota Motor Corp | Combustion control device for internal combustion engine |
| KR20040046822A (en) * | 2002-11-28 | 2004-06-05 | 현대자동차주식회사 | A method for air fuel raio control of go with sustenance on vehicle |
| JP2008095542A (en) * | 2006-10-06 | 2008-04-24 | Toyota Motor Corp | Control system of internal combustion engine |
| JP2009002170A (en) * | 2007-06-19 | 2009-01-08 | Toyota Motor Corp | Air-fuel ratio control device for internal combustion engine |
| JP2012087673A (en) * | 2010-10-19 | 2012-05-10 | Toyota Motor Corp | Control device of internal combustion engine |
| US20160265467A1 (en) * | 2015-03-12 | 2016-09-15 | Toyota Jidosha Kabushiki Kaisha | Exhaust purification system of internal combustion engine |
| JP2016169665A (en) * | 2015-03-12 | 2016-09-23 | トヨタ自動車株式会社 | Exhaust emission control device for internal combustion engine |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP4036395A1 (en) | 2021-01-28 | 2022-08-03 | Toyota Jidosha Kabushiki Kaisha | Controller for internal combustion engine, control method for internal combustion engine, and memory medium |
| US11448157B2 (en) | 2021-01-28 | 2022-09-20 | Toyota Jidosha Kabushiki Kaisha | Controller for internal combustion engine, control method for internal combustion engine, and memory medium |
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|---|---|
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