JP2004286026A - Engine exhaust emission control device - Google Patents

Engine exhaust emission control device Download PDF

Info

Publication number
JP2004286026A
JP2004286026A JP2004057888A JP2004057888A JP2004286026A JP 2004286026 A JP2004286026 A JP 2004286026A JP 2004057888 A JP2004057888 A JP 2004057888A JP 2004057888 A JP2004057888 A JP 2004057888A JP 2004286026 A JP2004286026 A JP 2004286026A
Authority
JP
Japan
Prior art keywords
engine
reference value
amount
regeneration
exhaust
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2004057888A
Other languages
Japanese (ja)
Other versions
JP4370942B2 (en
Inventor
Makoto Otake
真 大竹
Junichi Kawashima
純一 川島
Takao Inoue
尊雄 井上
Mitsunori Kondo
光徳 近藤
Toshimasa Koga
俊雅 古賀
Naoya Tsutsumoto
直哉 筒本
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nissan Motor Co Ltd
Original Assignee
Nissan Motor Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nissan Motor Co Ltd filed Critical Nissan Motor Co Ltd
Priority to JP2004057888A priority Critical patent/JP4370942B2/en
Publication of JP2004286026A publication Critical patent/JP2004286026A/en
Application granted granted Critical
Publication of JP4370942B2 publication Critical patent/JP4370942B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • 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)
  • Filtering Of Dispersed Particles In Gases (AREA)
  • Supercharger (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Processes For Solid Components From Exhaust (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deposition of minute particles caused by continuing idle operation while suppressing deterioration in fuel consumption due to recycling, in an exhaust emission control device recycling a filter for catching exhaust minute particles of an engine by exhaust temperature rise. <P>SOLUTION: When an idle operation state continues, filter recycling is conducted only after depositing amount of the exhaust fine particles becomes not less than a second depositing amount reference value PMe higher than a first depositing amount reference value PMn that is a determining reference of recycling under a high load. The reference value starting recycling is gradually set according to an engine operation state, so that the deposition of the exhaust fine particles can be suppressed while decreasing the number of opportunities for raising exhaust temperature that tends to deteriorate fuel consumption at the time of idle operation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明はエンジンの排気浄化装置に関し、詳しくはエンジン排気中の微粒子状物質を捕集するフィルタの再生処理技術の改良に関する。   The present invention relates to an exhaust gas purifying apparatus for an engine, and more particularly, to an improvement in a technique for regenerating a filter for trapping particulate matter in engine exhaust.

ディーゼルエンジン等から排出される微粒子状物質（以下「排気微粒子」という。）を浄化処理するためにエンジン排気系統にフィルタを設け、捕捉した排気微粒子を所定のインターバルで酸化もしくは焼却することによりフィルタ再生するようにした装置が知られている。
特開平６−５８１３７号公報 A filter is provided in the engine exhaust system for purifying particulate matter (hereinafter referred to as “exhaust particulates”) discharged from a diesel engine or the like, and the captured exhaust particulates are oxidized or incinerated at predetermined intervals to regenerate the filter. There is known an apparatus for performing such operations.
JP-A-6-58137

フィルタで捕捉した排気微粒子の処理には従来は電気ヒータを用いるものが多く提案されているが、近年では燃料噴射時期の遅角化や二次噴射などエンジン制御により排気温度を上昇させるようにしたものが構造、信頼性、コストの面から注目されている。しかしながら、従来のエンジン制御による処理手法では、発生熱量が少ないアイドル運転時には燃費悪化を避けるために再生を行わないようにしていたので、アイドル運転が長時間続くとフィルタ内に排気微粒子が過度に堆積してしまうおそれがあった。   Conventionally, many methods using an electric heater have been proposed to treat exhaust particulates captured by a filter. In recent years, exhaust temperature has been increased by engine control such as retarding fuel injection timing and secondary injection. Things are attracting attention in terms of structure, reliability, and cost. However, in the conventional processing method based on engine control, regeneration is not performed during idling operation with a small amount of generated heat in order to avoid deterioration of fuel efficiency, so if the idling operation continues for a long time, exhaust particulates will excessively accumulate in the filter. There was a risk of doing it.

本発明では、エンジン制御によりフィルタ再生を開始する基準値として、負荷の高いエンジン運転状態にて再生を開始させるための第１の堆積量基準値に加えて、これよりも大きな第２の堆積量基準値を設定し、アイドル時など負荷の低いエンジン運転状態では微粒子堆積量がこの第２の堆積量基準値以上となったときにフィルタ再生を開始させる。   According to the present invention, as the reference value for starting the filter regeneration by the engine control, in addition to the first deposition amount reference value for starting the regeneration in an engine operating state with a high load, a second deposition amount larger than this is set. A reference value is set, and filter regeneration is started when the amount of accumulated particulates becomes equal to or more than the second reference value of the accumulated amount in an engine operating state with a low load, such as during idling.

負荷の高い運転状態のときは排気微粒子の堆積量が第１の堆積量基準値以上となったときに排気温度上昇によりフィルタ再生が行われ、排気微粒子の堆積が抑制される。一方、アイドル時など負荷の低い運転状態が継続したときには、排気微粒子の堆積量が第１の堆積量基準値よりも高い第２の堆積量基準値以上となったときに初めてフィルタ再生が開始される。   In a high load operation state, when the amount of exhaust particulates becomes equal to or greater than the first reference value of the amount of accumulated particulates, filter regeneration is performed due to an increase in exhaust gas temperature, and the accumulation of exhaust particulates is suppressed. On the other hand, when an operation state with a low load such as during idling continues, the filter regeneration is started only when the amount of exhaust particulates becomes equal to or more than a second reference value of the deposition amount higher than the first reference value of the reference amount. You.

このように、フィルタ再生のためのエンジン制御を開始する基準値をエンジン運転状態に応じて段階的に設定したことにより、低負荷運転時において燃費悪化傾向となる排気温度上昇を行う機会を少なくしつつ排気微粒子の堆積を抑制することができる。   As described above, the reference value for starting the engine control for the filter regeneration is set stepwise according to the engine operating state, so that the opportunity to increase the exhaust gas temperature, which tends to deteriorate the fuel efficiency during the low load operation, is reduced. In addition, the accumulation of exhaust particulates can be suppressed.

以下本発明の実施形態を図面に基づいて説明する。図１は本発明を適用可能なエンジンシステムの一例を示している。図において、１はエンジンの本体、２は吸気通路、３は排気通路である。エンジン本体１には燃料噴射弁４と燃料噴射ポンプ５が取り付けられている。吸気通路２には、上流側からエアクリーナ６、エアフロメータ７、排気ターボチャージャ８のコンプレッサ９、インタークーラ１０、スロットルバルブ１１が介装されている。排気通路３には、上流側から排気ターボチャージャ８のタービン１２、排気微粒子を捕集するフィルタ（ＤＰＦ）１３が介装されている。１４と１５はそれぞれフィルタ１３の入口温度と出口温度を検出する温度センサ、１６はフィルタ１２の前後圧力差を検出する圧力センサである。１７は吸気通路２と排気通路３とを連通するＥＧＲ通路であり、その途中にＥＧＲバルブ１８とＥＧＲクーラ１９が介装されている。排気ターボチャージャ８はそのタービン１２に流入する排気の流速を加減することができる可変ノズル２０を備えている。２１はエンジン回転数およびクランク位置を検出するクランク角センサである。   Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example of an engine system to which the present invention can be applied. In the figure, reference numeral 1 denotes an engine main body, 2 denotes an intake passage, and 3 denotes an exhaust passage. A fuel injection valve 4 and a fuel injection pump 5 are attached to the engine body 1. In the intake passage 2, an air cleaner 6, an air flow meter 7, a compressor 9 of an exhaust turbocharger 8, an intercooler 10, and a throttle valve 11 are interposed from the upstream side. The exhaust passage 3 is provided with a turbine 12 of the exhaust turbocharger 8 and a filter (DPF) 13 for collecting exhaust particulates from the upstream side. Reference numerals 14 and 15 denote temperature sensors for detecting the inlet and outlet temperatures of the filter 13, respectively, and reference numeral 16 denotes a pressure sensor for detecting a pressure difference between the front and rear of the filter 12. Reference numeral 17 denotes an EGR passage connecting the intake passage 2 and the exhaust passage 3, and an EGR valve 18 and an EGR cooler 19 are interposed in the EGR passage. The exhaust turbocharger 8 includes a variable nozzle 20 that can adjust the flow rate of the exhaust gas flowing into the turbine 12. Reference numeral 21 denotes a crank angle sensor that detects an engine speed and a crank position.

２２はコントロールユニットであり、ＣＰＵ、メモリおよびその周辺装置からなるマイクロコンピュータにより構成されている。コントロールユニット２２は、前記各種センサからの信号に基づき、燃料噴射時期、燃料噴射量、スロットルバルブ開度、ＥＧＲ量、可変ノズル開度等を制御すると共に、フィルタ１３の微粒子堆積量を算出する堆積量算出手段およびエンジン制御により排気温度を上昇させる再生制御手段として機能する。   Reference numeral 22 denotes a control unit, which is configured by a microcomputer including a CPU, a memory, and peripheral devices thereof. The control unit 22 controls the fuel injection timing, the fuel injection amount, the throttle valve opening, the EGR amount, the variable nozzle opening, and the like based on signals from the various sensors, and calculates the amount of fine particles deposited on the filter 13. It functions as an amount calculation unit and a regeneration control unit that raises the exhaust gas temperature by engine control.

図２は、前記コントロールユニット２２により実行されるフィルタ再生制御のフローを表している。このフローは一定時間ごとに周期的に実行される。以下の説明およびフロー中で符号Ｓを付して示した数字は処理ステップ番号である。   FIG. 2 shows a flow of the filter regeneration control executed by the control unit 22. This flow is executed periodically at regular intervals. In the following description and the flow, the numbers indicated by reference symbols S are processing step numbers.

この制御では、まずＳ１にてエンジン運転状態としてバックグラウンドで常時的に検出している負荷Ｑと回転数Ｎｅとを用いて排気微粒子の堆積量ＰＭ１を算出する。負荷Ｑはその代表値として燃料噴射量指令値又はアクセルペダル開度を使用し、回転数Ｎｅはクランク角センサ２１の信号を読み取っている。微粒子堆積量の算出手法は種々知られているが、例えば図３に示したように負荷Ｑおよび回転数Ｎｅに応じて一定時間Δt１内にエンジンから排出される排気微粒子量（排出ＰＭ量）を割り当てたテーブルを実験的に作成しておき、その一定時間毎の読み取り値を積算することで、例えば、PM1=PM1(i)=PM(i-1)+f(Q,Ne)のように微粒子堆積量ＰＭ１を求められる。ここで、PM(i-1)は、前回、ステップＳ１で計算された微粒子堆積量である。PM1(i)は、現在の微粒子堆積量である。ＰＭ排出レートf(Q,Ne)は一定時間Δt１内にエンジンから排出される微粒子状物質量である。一定時間は、ステップＳ１が繰り返される時間間隔である。ＰＭ排出レートf(Q,Ne)は、図３のマップをルックアップして、エンジン負荷ＱおよびエンジンスピードＮｅに基づいて定められる。制御ルーチンスタート時にPM(i-1)は初期値PM0に設定されている。フィルタが完全に再生された後（ステップＳ１０の後）制御ルーチンがスタートする場合、初期値PM0はゼロである。フィルタが不完全に再生された後（ステップＳ８の後）制御ルーチンがスタートする場合、初期値PM0はゼロでない。   In this control, first, in S1, the deposition amount PM1 of the exhaust particulates is calculated using the load Q and the rotation speed Ne which are constantly detected in the background as the engine operation state. The load Q uses a fuel injection amount command value or an accelerator pedal opening as a representative value, and the number of revolutions Ne reads a signal from the crank angle sensor 21. Various methods for calculating the amount of accumulated particulates are known. For example, as shown in FIG. 3, the amount of exhaust particulates (the amount of exhaust PM) discharged from the engine within a predetermined time Δt1 according to the load Q and the rotation speed Ne is determined. By experimentally creating the assigned table and integrating the readings at regular intervals, for example, PM1 = PM1 (i) = PM (i-1) + f (Q, Ne) The particle deposition amount PM1 is obtained. Here, PM (i-1) is the particle deposition amount calculated in the previous step S1. PM1 (i) is the current amount of accumulated fine particles. The PM emission rate f (Q, Ne) is the amount of particulate matter emitted from the engine within a certain time Δt1. The certain time is a time interval at which step S1 is repeated. The PM emission rate f (Q, Ne) is determined based on the engine load Q and the engine speed Ne by looking up the map of FIG. At the start of the control routine, PM (i-1) is set to an initial value PM0. When the control routine starts after the filter has been completely regenerated (after step S10), the initial value PM0 is zero. When the control routine starts after the filter is incompletely reproduced (after step S8), the initial value PM0 is not zero.

Ｓ２では前記排気微粒子堆積量ＰＭ１が堆積量基準値ＰＭｎ以上であるか否かを判定する。ＰＭｎはフィルタ再生を行う必要があるか否かの第１の判定基準値となるものであり、ＰＭ＜ＰＭｎのときはフィルタ再生をする必要がないので何もせずにフローの初めに戻る。ＰＭ≧ＰＭｎのときは、Ｓ３にて平均運転状態を判定する。これは制御の安定性を確保するために、例えば過去５分間の運転状態（Ｑ，Ｎｅ）の平均値を算出し、それが図４に示したようなマップ上のどの点にあたるかを判定する。   In S2, it is determined whether or not the exhaust particulate accumulation amount PM1 is equal to or greater than the accumulation amount reference value PMn. PMn is a first criterion value for determining whether or not it is necessary to perform the filter regeneration. When PM <PMn, there is no need to perform the filter regeneration, so that the process returns to the beginning of the flow without doing anything. When PM ≧ PMn, the average operating state is determined in S3. In order to ensure the stability of the control, for example, the average value of the operating state (Q, Ne) for the past 5 minutes is calculated, and it is determined which point on the map as shown in FIG. .

前記領域判定においてアイドルを含む低負荷領域（図４のＡ領域）であると判定された場合には、次いでＳ４にて低負荷領域での堆積量ＰＭ２を前記ＰＭ１と同様のテーブル検索の手法で運転状態に応じて算出し、Ｓ５にてこれをＰＭ１に加えたものを新たにＰＭ１とする。   If it is determined in the area determination that the area is a low load area including the idle (the area A in FIG. 4), then in S4, the deposition amount PM2 in the low load area is determined by the same table search method as that for PM1. It is calculated according to the operating state, and in S5, a value obtained by adding this to PM1 is newly defined as PM1.

Ｓ６では現在の運転状態が低負荷領域(図４のＡ領域)内に維持されているかを判定し、維持されていればＳ７にて前記ＰＭ１を第２の堆積量基準値ＰＭｅと比較する。ＰＭｅは図５にも示したように第１の基準値ＰＭｎよりも大きく、フィルタ１３の許容最大堆積量Ｐｍａｘよりも小さな値に設定されている。例えば、ＰＭｅは、Ｐｍａｘの９０％、ＰＭｎはＰｍａｘの７０％に設定される。許容最大堆積量Ｐｍａｘは、それ以上ではフィルタの詰りによりエンジントラブルが発生する堆積量であるか、或いはそれ以上では微粒子がフィルタを通って外部に排出される堆積量である。この判定においてＰＭ１＜ＰＭｅであるときはＳ４の処理に戻り、低負荷領域である限りＰＭ２の算出およびＰＭ１の更新を繰り返す。   In S6, it is determined whether or not the current operation state is maintained within the low load region (A region in FIG. 4). If the current operation state is maintained, the PM1 is compared with the second reference value PMe in S7. PMe is set to a value larger than the first reference value PMn and smaller than the maximum allowable deposition amount Pmax of the filter 13 as shown in FIG. For example, PMe is set to 90% of Pmax, and PMn is set to 70% of Pmax. The allowable maximum deposition amount Pmax is a deposition amount above which an engine trouble occurs due to clogging of the filter, or a deposition amount above which particulates are discharged outside through the filter. If PM1 <PMe in this determination, the process returns to S4, and the calculation of PM2 and the update of PM1 are repeated as long as the load region is low.

Ｓ７の判断においてＰＭ１≧ＰＭｅとなったときには、Ｓ８においてバランスポイント再生処理（ＢＰＴ再生処理）を実施する。ＢＰＴ再生処理とは、この再生モード（Ｓ８）に入ったときに残存するフィルタ１３の微粒子堆積量を増やしもせず減らしもしないようにする制御のことである。これは、低車速走行の多い運転モードでは、フィルタ１３に堆積している微粒子のすべてを例えば５分間連続走行で燃焼し切るには無理があるので、フィルタ１３の微粒子堆積量を増やすこともせず減らすこともしないように現状を維持させ、車速が高速度側の再生モード（Ｓ１０）になったときに、フィルタ１３に堆積している微粒子のすべてを例えば５分間連続走行で燃焼し切るようにするものである。   When PM1 ≧ PMe in the determination of S7, the balance point regeneration process (BPT regeneration process) is performed in S8. The BPT regeneration process is a control for preventing the remaining amount of fine particles of the filter 13 from increasing or decreasing when the regeneration mode (S8) is entered. This is because, in the operation mode in which the vehicle travels at a low speed, it is impossible to completely burn all of the fine particles deposited on the filter 13 by, for example, continuous running for 5 minutes. The current state is maintained so as not to reduce it, and when the vehicle speed enters the regeneration mode (S10) on the high speed side, all the particulates deposited on the filter 13 are burned off by continuous running, for example, for 5 minutes. Is what you do.

具体的には、再生処理を開始し、排気温度を目標値（約４００℃）へと上昇させると、フィルタ１３に堆積している微粒子が穏やかに燃焼する。その一方で、フィルタ１３の再生処理中にも排気中の微粒子が流入してきてフィルタ１３のベッドに堆積する。そこで、フィルタ１３に流入してきてベッドに堆積する微粒子の量と、燃焼によりベッドより消失する微粒子量とが一致するようにフィルタ１３に流入してくる微粒子量を調整する（減少させる）。   Specifically, when the regeneration process is started and the exhaust gas temperature is raised to a target value (about 400 ° C.), the fine particles deposited on the filter 13 burn gently. On the other hand, even during the regeneration process of the filter 13, the fine particles in the exhaust gas flow in and accumulate on the bed of the filter 13. Therefore, the amount of the fine particles flowing into the filter 13 is adjusted (decreased) so that the amount of the fine particles flowing into the filter 13 and accumulating on the bed coincides with the amount of the fine particles disappearing from the bed due to combustion.

図２Ａ内、Ｓ１１、１２、１３がＢＰＴ再生処理のフローチャートである。Ｓ１１では排気温度を目標値（約４００℃に設定）まで昇温手段を用いて上昇させる。昇温手段としては、メイン噴射を制御するもの、メイン噴射時期をリタードするもの、吸気絞り（吸気量制御）を行うもの、燃料のポスト噴射量を増加させるもの、ポスト噴射時期をリタードさせるもの、可変ノズル排気ターボチャージャのノズル開度制御、ＥＧＲ制御が考えられる。また、昇温手段として、エアコンプレッサやオルタネータなどの補機類の負荷を増大すること（補機類負荷制御）も考えられる。なお、ＢＰＴ再生では、排気温度上昇制御に伴う燃費の悪化を最小限に抑制できる。   In FIG. 2A, S11, S12, and S13 are flowcharts of the BPT playback processing. In S11, the exhaust gas temperature is raised to a target value (set at about 400 ° C.) using a temperature raising means. As the temperature raising means, those for controlling the main injection, those for retarding the main injection timing, those for performing the intake throttle (intake amount control), those for increasing the post injection amount of the fuel, those for retarding the post injection timing, The nozzle opening degree control and the EGR control of the variable nozzle exhaust turbocharger can be considered. It is also conceivable to increase the load of auxiliary equipment such as an air compressor and an alternator (accessory load control) as the temperature raising means. In the BPT regeneration, it is possible to minimize deterioration of fuel efficiency due to the exhaust gas temperature rise control.

Ｓ１２では、スモーク低減運転を行い、Ｓ１３ではフィルタ１３の前後差圧が増加したかどうかをみる。フィルタ１３前後差圧が増加すれば、フィルタ１３に流入してベッドに堆積する微粒子量のほうが、燃焼によりベッドより消失する微粒子量を上回っていると判断してＳ１２に戻りスモーク低減運転を継続する。   In S12, the smoke reduction operation is performed, and in S13, it is determined whether the pressure difference across the filter 13 has increased. If the differential pressure across the filter 13 increases, it is determined that the amount of fine particles flowing into the filter 13 and accumulating on the bed is greater than the amount of fine particles disappearing from the bed due to combustion, and the process returns to S12 to continue the smoke reduction operation. .

ここで、スモーク低減とは微粒子低減の別表現であり、フィルタ１３前後差圧が増加すればスモーク低減運転を行うことで、この再生モードに入ったときに残存するフィルタ１３の微粒子堆積量を、増やしもせず減らしもしないようにすることができる。   Here, the smoke reduction is another expression of the particle reduction. When the pressure difference before and after the filter 13 increases, the smoke reduction operation is performed, so that the particle accumulation amount of the filter 13 remaining when entering the regeneration mode is reduced. It can be neither increased nor decreased.

Ｓ１２の機能を果たす手段（スモーク低減運転手段）としては、ＥＧＲ量を低減するもの、パイロット噴射量を低減するもの（ディーゼルエンジンの場合）、パイロット噴射のインターバルを大きくするもの、吸気ポートのすぐ上流位置に設けているスワールコントロールバルブを閉じてスワール強さを強化するものが考えられる。   Means that fulfill the function of S12 (smoke reduction operation means) include those that reduce the amount of EGR, those that reduce the amount of pilot injection (in the case of a diesel engine), those that increase the interval of pilot injection, and those that are immediately upstream of the intake port. A swirl control valve provided at the position may be closed to enhance the swirl strength.

また、Ｓ１３でフィルタ前後差圧が増加したか否かを判断するには、例えば次のようにすればよい。すなわち、この再生モードに入った直後のフィルタ１３の前後差圧を差圧センサ１６により検出してこれをメモリに記憶しておき、その後に差圧センサ１６により検出される実際のフィルタ前後差圧とこのメモリ値を比較し、実際のフィルタ前後差圧がこのメモリ値より増えるとフィルタ前後差圧が増加したと、この逆に実際のフィルタ前後差圧がこのメモリ値以下であればフィルタ前後差圧が増加していないと判断させればよい。   To determine whether or not the differential pressure across the filter has increased in S13, for example, the following may be performed. That is, the differential pressure across the filter 13 immediately after entering the regeneration mode is detected by the differential pressure sensor 16 and stored in a memory, and then the actual differential pressure between the filters detected by the differential pressure sensor 16 is detected. This memory value is compared with the memory value. When the actual differential pressure across the filter increases below this memory value, the differential pressure across the filter increases. What is necessary is just to let it judge that pressure is not increasing.

一方、前記Ｓ３またはＳ６の運転領域判断において高負荷領域と判定された場合には、Ｓ１０の高負荷領域での再生処理のサブルーチンを実施する。これは、例えば図４に示した比較的低負荷のＢ領域では燃費悪化を抑制するために定量再生を行い、より負荷が高く排気の熱量も大きいＣ領域では再生のための燃費の負担が少ないことから堆積微粒子がなくなるまで処理を続ける完全再生を行う。なお、Ｄ領域は排気温度制御を行うまでもなく再生に十分な排気温度が得られる自然再生領域である。   On the other hand, if it is determined in the operation region determination of S3 or S6 that the region is a high load region, a subroutine of the regeneration process in the high load region of S10 is performed. This is because, for example, in the relatively low load B region shown in FIG. 4, quantitative regeneration is performed in order to suppress the deterioration of fuel efficiency, and in the C region where the load is higher and the calorific value of the exhaust gas is large, the burden of the fuel consumption for regeneration is small. For this reason, complete regeneration is performed, in which the processing is continued until the accumulated fine particles disappear. The region D is a natural regeneration region in which an exhaust gas temperature sufficient for regeneration can be obtained without performing exhaust gas temperature control.

この制御では、低負荷領域内での運転域判断処理（Ｓ６）では瞬時運転状態にて高負荷時再生処理に移行させているが、これにより再生効率の高い高負荷運転状態への移行に対応して速やかに再生を行わせることができる。この高負荷時再生処理が終了した後は再び図２の処理の当初に戻り、微粒子堆積量と運転領域に応じた再生処理を繰り返す。   In this control, in the operation range determination process in the low load region (S6), the process is shifted to the high load regeneration process in the instantaneous operation state. Then, the reproduction can be promptly performed. After the end of the high load regeneration process, the process returns to the beginning of the process of FIG. 2 again, and the regeneration process according to the amount of accumulated fine particles and the operation region is repeated.

本発明の排気浄化装置は、ディーゼルエンジンなどの自動車エンジンの排気浄化装置として利用できる。   The exhaust gas purification device of the present invention can be used as an exhaust gas purification device for an automobile engine such as a diesel engine.

本発明を適用可能なエンジンシステムの概略図。1 is a schematic diagram of an engine system to which the present invention can be applied. 本発明の一実施形態に係る再生制御の処理手順を示す流れ図。5 is a flowchart showing a processing procedure of reproduction control according to an embodiment of the present invention. ＢＰＴ再生処理の処理手順を示す流れ図。9 is a flowchart showing a processing procedure of a BPT reproduction process. 前記再生制御で用いる堆積量算出のためのテーブルの説明図。FIG. 4 is an explanatory diagram of a table for calculating a deposition amount used in the regeneration control. 運転領域の説明図。Explanatory drawing of an operation area. 堆積量の基準値の説明図。FIG. 4 is an explanatory diagram of a reference value of a deposition amount.

符号の説明Explanation of reference numerals

１ エンジン本体
２ 吸気通路
３ 排気通路
４ 燃料噴射弁
５ 燃料噴射ポンプ
７ エアフロメータ
８ 排気ターボチャージャ
９ コンプレッサ
１１ スロットルバルブ
１２ タービン
１３ フィルタ
１７ ＥＧＲ通路
１８ ＥＧＲバルブ１８
２０ ターボチャージャの可変ノズル
２１ クランク角センサ
２２ コントロールユニット DESCRIPTION OF SYMBOLS 1 Engine main body 2 Intake passage 3 Exhaust passage 4 Fuel injection valve 5 Fuel injection pump 7 Air flow meter 8 Exhaust turbocharger 9 Compressor 11 Throttle valve 12 Turbine 13 Filter 17 EGR passage 18 EGR valve 18
20 Variable nozzle of turbocharger 21 Crank angle sensor 22 Control unit

Claims (8)

エンジンの排気微粒子を捕集するフィルタと、
負荷を含むエンジン運転状態を検出する手段と、
エンジン運転状態に基づいてフィルタの微粒子堆積量を算出する堆積量演算手段と、
エンジン制御により排気温度を上昇させるフィルタ再生制御手段と、を備え、
前記再生制御手段は、高負荷の運転状態において再生を開始する第１の堆積量基準値と、アイドル運転状態において再生を開始する第２の堆積量基準値とを有し、かつ前記第２の堆積量基準値は第１の堆積量基準値よりも大に設定されていること
を特徴とするエンジンの排気浄化装置。 A filter for collecting engine exhaust particulates,
Means for detecting an engine operating state including a load;
A deposition amount calculating means for calculating a particulate deposition amount of the filter based on an engine operating state;
Filter regeneration control means for raising the exhaust gas temperature by engine control,
The regeneration control means has a first accumulation amount reference value for starting regeneration in a high-load operation state, a second accumulation amount reference value for starting regeneration in an idling operation state, and the second accumulation amount reference value. An exhaust gas purifying apparatus for an engine, wherein the reference value of the accumulation amount is set to be larger than the first reference value of the accumulation amount. 前記再生制御手段は、
再生を開始する第２の堆積量基準値を適用する運転状態として、アイドル運転状態と所定の低負荷運転状態が設定されている請求項１に記載のエンジンの排気浄化装置。 The reproduction control means includes:
The engine exhaust gas purification apparatus according to claim 1, wherein an idle operation state and a predetermined low-load operation state are set as operation states to which the second accumulation amount reference value for starting regeneration is applied. 前記再生制御手段は、
第２の堆積量基準値を適用する低負荷の運転状態では、フィルタに流入して堆積する微粒子量と燃焼により消失する微粒子量とを一致させるバランスポイント再生を行う請求項１または請求項２に記載のエンジンの排気浄化装置。 The reproduction control means includes:
3. The balance point regeneration according to claim 1 or 2, wherein in a low-load operation state to which the second accumulation amount reference value is applied, the balance point regeneration is performed so that the amount of the fine particles flowing into the filter and accumulating and the amount of the fine particles disappeared by combustion are matched. An exhaust gas purifying apparatus for an engine according to the above. 前記再生制御手段は、
第１の堆積量基準値を適用する高負荷の運転状態では完全再生を行う請求項１または請求項２に記載のエンジンの排気浄化装置。 The reproduction control means includes:
The exhaust gas purifying apparatus for an engine according to claim 1 or 2, wherein complete regeneration is performed in a high-load operating state to which the first accumulation reference value is applied. 前記再生制御手段は、
前記何れの堆積量基準値を適用するかを、運転状態を所定時間平均した結果に基づいて決定し、ただし第２の堆積量基準値に基づく再生中は、運転状態が第１の堆積量基準値を適用すべき高負荷の運転状態となったときただちに第１の堆積量基準値による再生制御に移行する請求項４に記載のエンジンの排気浄化装置。 The reproduction control means includes:
Which of the above-mentioned accumulation amount reference values is to be applied is determined based on the result of averaging the operation state for a predetermined time. However, during regeneration based on the second accumulation amount reference value, the operation state becomes the first accumulation amount reference value. 5. The exhaust gas purifying apparatus for an engine according to claim 4, wherein the control immediately proceeds to the regeneration control based on the first reference value of the accumulation amount when a high load operation state to which the value is applied is set. 前記排気温度を上昇させるエンジン制御は、
燃料噴射時期制御、燃料噴射量制御、可変ノズル排気ターボチャージャのノズル開度制御、ＥＧＲ制御、吸気量制御、補機類負荷制御、の何れかを適用して行う請求項１または請求項２に記載のエンジンの排気浄化装置。 The engine control for increasing the exhaust gas temperature includes:
The fuel injection timing control, the fuel injection amount control, the nozzle opening control of the variable nozzle exhaust turbocharger, the EGR control, the intake air amount control, and the auxiliary equipment load control are performed by applying any one of claims 1 and 2. An exhaust gas purifying apparatus for an engine according to the above. 前記再生制御手段は、
エンジン運転状態を負荷とエンジン回転数とに基づいて判定する請求項１または請求項２に記載のエンジンの排気浄化装置。 The reproduction control means includes:
3. The engine exhaust purification device according to claim 1, wherein the engine operation state is determined based on the load and the engine speed. 前記堆積量演算手段は、
エンジン負荷と回転数とから微粒子堆積量を与えるテーブルを参照することにより堆積量を算出する請求項１または請求項２に記載のエンジンの排気浄化装置。 The accumulation amount calculating means includes:
3. The engine exhaust purification device according to claim 1, wherein the amount of accumulation is calculated by referring to a table that gives the amount of accumulated particles from the engine load and the number of revolutions.
JP2004057888A 2003-03-03 2004-03-02 Engine exhaust purification system Expired - Fee Related JP4370942B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004057888A JP4370942B2 (en) 2003-03-03 2004-03-02 Engine exhaust purification system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2003055658 2003-03-03
JP2004057888A JP4370942B2 (en) 2003-03-03 2004-03-02 Engine exhaust purification system

Publications (2)

Publication Number Publication Date
JP2004286026A true JP2004286026A (en) 2004-10-14
JP4370942B2 JP4370942B2 (en) 2009-11-25

Family

ID=33301987

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004057888A Expired - Fee Related JP4370942B2 (en) 2003-03-03 2004-03-02 Engine exhaust purification system

Country Status (1)

Country Link
JP (1) JP4370942B2 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1754876A3 (en) * 2005-08-18 2008-07-23 Kabushiki Kaisha Toyota Jidoshokki Exhaust purifier for diesel engine
CN103711557A (en) * 2013-12-27 2014-04-09 清华大学 Testing method and device for balance temperature of particulate filter
JP2014185644A (en) * 2014-06-05 2014-10-02 Yanmar Co Ltd Engine device
JP2020045825A (en) * 2018-09-19 2020-03-26 いすゞ自動車株式会社 Control device and pressure control method
JP2021008862A (en) * 2019-07-02 2021-01-28 三菱自動車工業株式会社 Internal combustion engine intake apparatus

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1754876A3 (en) * 2005-08-18 2008-07-23 Kabushiki Kaisha Toyota Jidoshokki Exhaust purifier for diesel engine
US7454897B2 (en) 2005-08-18 2008-11-25 Kabushiki Kaisha Toyota Jidoshokki Exhaust purifier for diesel engine
CN103711557A (en) * 2013-12-27 2014-04-09 清华大学 Testing method and device for balance temperature of particulate filter
JP2014185644A (en) * 2014-06-05 2014-10-02 Yanmar Co Ltd Engine device
JP2020045825A (en) * 2018-09-19 2020-03-26 いすゞ自動車株式会社 Control device and pressure control method
JP2021008862A (en) * 2019-07-02 2021-01-28 三菱自動車工業株式会社 Internal combustion engine intake apparatus
JP7310371B2 (en) 2019-07-02 2023-07-19 三菱自動車工業株式会社 Intake system for internal combustion engine

Also Published As

Publication number Publication date
JP4370942B2 (en) 2009-11-25

Similar Documents

Publication Publication Date Title
US7062906B2 (en) Regeneration of particulate filter
US7219493B2 (en) Filter regeneration in engine exhaust gas purification device
JP2004218484A (en) Regenerator for particulate filter, and exhaust emission control device for engine
KR20030022042A (en) Exhaust emission control device for engine
JP2004197657A (en) Reproducing apparatus for particulate filter and engine waste gas purifying facility
JP2006226119A (en) Exhaust emission control device for internal combustion engine
JP2004211650A (en) Exhaust gas cleaner of engine
JP2002303123A (en) Exhaust emission control device
JP2004197584A (en) Regenerative device for particulate filter and exhaust emission control device
EP2924270B1 (en) Exhaust gas purification system and exhaust gas purification method
JP2005048740A (en) Exhaust emission control device for engine, and particulate accumulation state determination method for particulate collection filter
JP2005264785A (en) Exhaust gas aftertreatment device of diesel engine
US7065959B2 (en) Filter regeneration control
JP4544011B2 (en) Internal combustion engine exhaust purification system
JP2003083036A (en) Regeneration control device for particulate filter
JP2004197722A (en) Reproducing apparatus of particulate filter and engine waste gas purifying facility
JP2004308439A (en) Exhaust emission cleaning device
JP5370252B2 (en) Exhaust gas purification device for internal combustion engine
JP4370942B2 (en) Engine exhaust purification system
JP2008180107A (en) Exhaust emission purifier of diesel engine
JP2008144726A (en) Exhaust emission control device for internal combustion engine
JP2008232073A (en) Exhaust emission purifier
JP4120545B2 (en) Engine exhaust purification system
JP4333230B2 (en) Exhaust gas purification system for internal combustion engine
JP2010169032A (en) Engine control device

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20070228

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20090731

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20090811

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20090824

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20120911

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20120911

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130911

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140911

Year of fee payment: 5

LAPS Cancellation because of no payment of annual fees