JP3709715B2 - Vehicle driving force control device - Google Patents

Description

ただし、G:ＣＶＴ変速比
Gf:ファイナルギアの減速比
J1:エンジンおよびＣＶＴの入力側の慣性モーメント
J2:ＣＶＴ出力からファイナルギア入力までの慣性モーメント
J3:ファイナルギアから駆動輪までの慣性モーメント
ω_W:車輪の角速度
なお、▲２▼式右辺カッコ内の第２項のdω_W/dtは角速度ω_Wの変化率であるが、車輪速V_Wの変化率dV_W/dtとの間にはdV_W/dt＝R・dω_W/dtの関係があり、その差は比例定数としてのRでしかないこと、また角速度より車輪速のほうがよく使われることから、以下ではω_Wを車輪速、dω_W/dtを車輪速の変化率という。また、駆動輪と従動輪を区別するときは、ω_W1を駆動輪速、dω_W1/dtを駆動輪速の変化率、またω_W2を従動輪速、dω_W2/dtを従動輪速の変化率という。
【００４０】
ここで、▲２▼式の右辺カッコ内の第３項が変速比の時間的変化に対応した（変速比の変化率dG/dtに比例した）イナーシャトルク分の補正量、同じく第２項が車輪速の時間的変化に対応した（車輪速の変化率dω_W/dtに比例した）イナーシャトルク分の補正量である。
【００４１】
▲２▼式において、変速比Gと車輪速ω_Wが分かれば、これらと車両の諸元値（Gf、J1、J2、J3）を用いて、▲２▼式の右辺カッコ内の第２項、第３項のトルク補正量を演算することができ、これらのトルク補正量で右辺カッコ内の第１項の目標駆動トルクtTdを補正することにより、目標エンジントルクtTeを求めることができる。
【００４２】
しかしながら、従来装置では▲２▼式の右辺カッコ内の第２項を省略した次式、
【００４３】
【数３】
tTe＝(１/(G・Gf))×｛tTd＋J1・ω_W・G・Gf²・(dG/dt)｝ …▲３▼
によって目標エンジントルクtTeを演算していた。つまり従来は変速比の時間的変化に対応したイナーシャトルク分だけの補正であったので、加減速時に目標駆動トルクが得られず、運転者の意図した通りの車両挙動を実現できなかったわけである。
【００４４】
これに対処するため本発明では、目標エンジントルクを上記の▲２▼式で演算することにより、加減速時に車輪速の時間的変化に対応したイナーシャトルクの影響を受けても、目標駆動トルクからのずれが生じないようにする。たとえば、加速動作が行われた場合に、▲３▼式を用いて目標エンジントルクを算出したときは、図４に示したように、車体速が変化している間は目標駆動トルクが得られないのに対して、図４と同じ条件で、▲２▼式を用いて目標エンジントルクを算出したときは、図５のように車体速が変化している間も目標駆動トルクを精度良く実現することが可能となるのである。
【００４５】
しかしながら、上記の▲２▼式を用いる場合、右辺カッコ内の第２項（車輪速の時間的変化に対応したイナーシャトルク分の補正量）に車輪速変化率dω_W/dtが入っているため、車輪速を駆動輪で検出している場合に、駆動輪にホイールスピンが生じたときは、同第２項の影響により車輪速（エンジン回転）が急激に上昇する可能性がある。
【００４６】
そこで、いま駆動輪にホイールスピンが生じていないと仮定すると、次式
【００４７】
【数４】
(F−Fr)/M＝R・(dω_W/dt) …▲４▼
ただし、F:駆動力
Fr:走行抵抗
M:車両質量
R:タイヤ有効半径
が成り立つ。
【００４８】
ここで、エンジンの遅れは微小であると仮定し、この▲４▼式を用いて▲２▼式を変形すると、次式
【００４９】
【数５】

に変形される。
【００５０】
ただし、▲５▼式右辺カッコ内の第２項の係数αは
【００５１】
【数６】
α＝(J1・G²・Gf²＋J2・Gf²＋J3)/(M・R²) …▲６▼
である（Gと車両の諸元により定まる値）。
【００５２】
この数５式右辺カッコ内の第２項の（ tTd − Fr ・ R ）・α（第２補正量相当）は、車輪速変化率dω_W/dtを陽に含んでいないため、数２式を用いた場合のように車輪速（エンジン回転）が急激に上昇する可能性はない。よって、数５式を用いれば、ホイールスピンを生じていないときは目標駆動トルクを精度良く実現でき、また、ホイールスピンを生じるような低μ路でも、車輪速（エンジン回転）が急激に上昇するのを防止できる。
【００５３】
たとえば、低μ路において、図４、図５の場合と同じ条件で加速動作が行われた場合の作用を図６、図７に示すと、▲２▼式を用いて目標エンジントルクの算出したときは図６のようになり、ひとたびホイールスピンが生じると、駆動トルクは所望の値を実現できないまま駆動輪速のみが上昇する現象が生じている。これに対して、▲５▼式を用いて目標エンジントルクを算出したときは図７のようになり、ホイールスピンが生じても駆動輪速の上昇を防止できている。ホイールスピンが生じていないとき（図５参照）と比較すれば、精度は若干落ちるものの駆動トルクもほぼ目標値を実現することができている。
【００５４】
このように本発明では、▲２▼式または▲５▼式を用いて目標エンジントルクを算出することになると、車輪速に駆動輪の車輪速を用いるのか、従動輪の車輪速を用いるのかをも考え合わせて、次の５つの実施形態が考えられる。
【００５５】
〈１〉ホイールスピンを生じていないとき駆動輪速を用いて▲２▼式により、またホイールスピンを生じたとき従動輪速を用いて▲２▼式により目標エンジントルクを演算する。
【００５６】
〈２〉ホイールスピンの有無に関係なく、常に従動輪速を用いて▲２▼式により目標エンジントルクを演算する。
【００５７】
〈３〉ホイールスピンの有無に関係なく、▲５▼式により目標エンジントルクを演算する。
【００５８】
〈４〉ホイールスピンを生じていないときは、▲５▼式より▲２▼式のほうが精度良く目標駆動トルクを実現できるため、ホイールスピンを生じていないとき、▲２▼式を用いて、またホイールスピンを生じたとき▲５▼式を用いて目標エンジントルクを演算する。
【００５９】
〈５〉加減速時にだけ車輪速の時間的変化に対応したイナーシャトルク分の補正量（▲２▼式、▲５▼式の右辺カッコ内の各第２項）を演算する。
【００６０】
なお、上記の〈３〉、〈４〉において▲５▼式を用いるときは、▲５▼式右辺カッコ内の第２項の演算に走行抵抗Frが必要である。この場合、一般に車体速と走行抵抗Frとの間には後述する図１８のような関係があるため、図１８のデータをテーブル値としてプログラム中に持たせておけば、車体速から走行抵抗Frを求めることができる。また、車体速に代えて従動輪速あるいは駆動輪速を用いても、およその走行抵抗Frの値を演算することができる。さらに、▲５▼式右辺カッコ内の第２項において、走行抵抗Frの項（Fr・R）が目標駆動トルクtTdに対して微小であれば、運転条件によらず常に一定値あるいはこの項を無視（Fr＝０に相当）してもよい。
【００６１】
上記の〈１〉、〈４〉、〈５〉においては、ホイールスピンが生じたときと生じていないときとで目標エンジントルクの演算式を切換えなければいけないので、この切換に伴って制御のハンチングが生じないようにする必要がある。
【００６２】
以下、フローチャートを用いて具体的に説明する。
【００６３】
なお、上記の〈１〉〜〈５〉の順に対応して、後述する図８、図１５、図１６、図１７、図１９の各フローチャートが組まれている。
【００６４】
図８のフローチャートは第１実施形態で、10ms毎に実行する。
【００６５】
ステップ1101では、スロットルセンサにより検出されるアクセル操作量APS、車速センサにより検出される車体速V_V、駆動輪速センサ（図２参照）により検出される駆動輪速ω_W1、従動輪速センサ（図２参照）により検出される従動輪速ω_W2、ＣＶＴの実変速比（駆動輪速とＣＶＴ入力軸回転数に基づいて計算される）Gを読み込む。
【００６６】
このうちアクセル操作量APSと車体速V_Vから、ステップ1102において図９を内容とするマップを検索して目標駆動トルクtTdを求める。
【００６７】
ステップ1103では、実変速比Gからその変化率dG/dtを計算する。この値は変速制御の目標変速比を用いて計算してもかまわない。
【００６８】
ステップ1104、1105では駆動輪速ω_W1からその変化率dω_W1/dtを、従動輪速ω_W2からその変化率dω_W2/dtをそれぞれ計算する。
【００６９】
ステップ1106では、フラグFSPINをみる。このフラグFSPINは、FSPIN＝１のときホイールスピンが生じていることを、またFSPIN＝０のときホイールスピンが生じていないことを表す。このフラグの設定（ホイールスピンの有無の判定）については図１０〜図１２のフローにより説明する。
【００７０】
図１０〜図１２のフローは図８のフローと独立に10ms毎に実行する。
【００７１】
まず図１０から説明すると、ステップ1201、1202で駆動輪速ω_W1と従動輪速ω_W2を読み込み、これらの速度差dω（＝ω_W1−ω_W2）をステップ1203において計算する。
【００７２】
ステップ1204〜1206はヒステリシスつきのホイールスピンの有無判定部分で、上記の速度差dωが第１判定値dωHを超えたときホイールスピンが発生したと判断し、速度差dωが第１判定値dωHよりも小さな第２判定値dωL以下になったときホイールスピンは発生していないと判断する。
【００７３】
詳細には、ステップ1204でフラグFSPIN（“０”に初期設定）をみる。初期設定の状態であれば、FSPIN＝０よりステップ1205に進み、速度差dωと第１判定値dωHを比較する。dω＞dωHであるときはホイールスピンが発生したと判断し、ステップ1207に進んでFSPIN＝１として今回の処理を終了する。
【００７４】
このFSPIN＝１より次回からはステップ1204よりステップ1206に進み、今度は速度差dωと第２判定値dωLを比較する。ここで、第２判定値dωLは第１判定値dωHより小さな値である。dω≧dωLであるときはステップ1207の処理を行って（つまりフラグの値はそのまま）今回の処理を終了する。dωがdωL未満となったときホイールスピンが発生していないと判断し、ステップ1206よりステップ1208に進んでFSPIN＝０とする。
【００７５】
上記２つの判定値dωH、dωLは定数でも良いし、スロットル開度、車速等の運転条件に基づくテーブル値、マップ値などでもよい。
【００７６】
このように、フラグFSPINの“０”から“１”への、あるいはその逆への切換にヒステリシスを設けることで、ハンチングの発生を防止できる。
【００７７】
図１０のフローではヒステリシスによってハンチングの発生を防止したのに対して、図１１のフローは、ホイールスピンが実際に生じなくなったときから所定の時間の経過後にフラグFSPINを“１”から“０”へと切換えることにより、ハンチングの発生を防止するものである。
【００７８】
なお、図１０と同一部分には同一のステップ番号を付けており、図１０と異なる部分を中心に説明する。
【００７９】
ステップ1205で速度差dωが判定値dωHより大きいときはステップ1207に進んでフラグFSPIN＝１とした後、ステップ1301でカウンタTを０にリセットして今回の処理を終了する。
【００８０】
速度差dωがdωH以下になるとホイールスピンが生じなくなったと判断し、ステップ1205よりステップ1302に進んでカウンタTと所定値T0を比較する。ここで、所定値T0は経過時間を定める値である。T0は定数でも良いし、スロットル開度、車速等の運転条件に基づくテーブル値、マップ値などでもよい。
【００８１】
カウンタTが所定値T0以下であれば、ステップ1303、1304に進み、フラグFSPIN＝１とするとともに、カウンタTを１インクリメントして今回の処理を終了する。
【００８２】
dω≦dω_Hの状態でステップ1304のインクリメントが繰り返され、やがてT＞T0となった（つまりホイールスピンが生じなくなったときから所定の時間T0が経過した）とき、ステップ1208に進んでフラグFSPIN＝０とする。
【００８３】
図１０、図１１では駆動輪速ω_W1と従動輪速ω_W2の速度差dωに基づいてホイールスピンの有無を判定する構成としたが、これに限るものでなく、両車輪速の比率に基づいてホイールスピンの有無を判定する構成としてもよい。
【００８４】
図１２のフローは、駆動輪速の変化率に基づいてホイールスピンの有無を判定するようにしたものである。図１０と同一部分には同一のステップ番号を付けており、図１１と異なる部分を中心に説明する。
【００８５】
初期設定の状態であれば、FSPIN＝０であるので、ステップ1204よりステップ1401に進み、駆動輪速ω_W1からその変化率dω_W1/dtを計算し、この変化率dω_W1/dtと判定値dω_W1H/dtをステップ1402において比較する。
【００８６】
dω_W1/dt≦dω_W1H/dtであるときは、ホイールスピンが生じていないので、ステップ1402よりステップ1403に進み、フラグFSPIN＝０として今回の処理を終了する。dω_W1/dt＞dω_W1H/dtになるとホイールスピンが生じたと判断し、ステップ1402よりステップ1207に進み、FSPIN＝１として今回の処理を終了する。
【００８７】
一方、FSPIN＝１のときは、ステップ1204より1404に進み、駆動輪速ω_W1と判定値ω_W1Hを比較する。
【００８８】
駆動輪速ω_W1が判定値ω_W1Hを超えているときは、まだスリップが生じていると判断し、ステップ1207でフラグFSPIN＝１として今回の処理を終了する。やがて、ω_W1≦ω_W1Hとなれば、スリップがやんだとしてステップ1404よりステップ1208に進み、FSPIN＝０として今回の処理を終了する。
【００８９】
上記の判定値dω_W1H/dtとω_W1Hは、たとえばスロットル開度、車速等の運転条件に基づくテーブル値、マップ値などである。判定値dω_W1H/dtのマップの例を図１３に、判定値ω_W1Hのマップの例を図１４に示す。
【００９０】
以上、図１０〜図１２によりフラグFSPINの設定について３つの方法を説明したが、いずれを用いてもかまわない。
【００９１】
図８に戻り、フラグFSPIN＝０（ホイールスピンが生じていない）のときはステップ1108に進み、駆動輪速変化率dω_W1/dtを用いて前述の▲２▼式により目標エンジントルクtTeを、これに対して、FSPIN＝１（ホイールスピンが生じている）のときはステップ1107に進み、従動輪速変化率dω_W2/dtを用いて前述の▲２▼式により目標エンジントルクtTeを演算する。
【００９２】
このように第１実施形態は、目標エンジントルクの演算に前述の▲２▼式を用い、ホイールスピンの有無により演算に用いる車輪速変化率を切換えるようにしたので、ホイールスピンが生じても車輪速の急激な上昇が生じることがなく、また、ホイールスピンが生じていないときは高精度に目標駆動トルクを実現することができる。
【００９３】
図１５は第２実施形態で、第１実施形態の図８に対応する。図８と同一部分には同一のステップ番号を付けている。
【００９４】
第２実施形態は、ホイールスピンの有無に関係なく、常に従動輪速の変化率dω_W2/dtを用いて前述の▲２▼式により目標エンジントルクtTeを演算するようにしたもので、この実施形態によっても、第１実施形態と同様の作用効果が生じる。
【００９５】
なお、フラグFSPINによる切換が無くなった以外、各ステップは第１実施形態の図８と同じであるので、詳細な説明は省略する。
【００９６】
図１６は第３実施形態、図１７は第４実施形態で、第１実施形態の図８に対応する。図８と同一部分には同一のステップ番号を付けている。
【００９７】
図１６の第３実施形態は、ホイールスピンの有無に関係なく前述の▲５▼式により目標エンジントルクtTeを演算するようにしたもの、図１７の第４実施形態は、ホイールスピンが生じていないとき前述の▲２▼式に基づいて、またホイールスピンが生じているとき前述の▲５▼式に基づいてそれぞれ目標エンジントルクを演算するようにしたもので、これら２つの実施形態によっても、第１実施形態と同様の作用効果が生じる。
【００９８】
図１６、図１７において、図８と異なる部分を主に説明すると、ステップ1601で変速比Gを用いて上記の▲６▼式により係数αを計算し、ステップ1602では車体速V_Vから図１８を内容とするテーブルを検索して走行抵抗Frを求める。ステップ1603ではこれらの係数α、走行抵抗Frを用いて前述の▲５▼式により目標エンジントルクtTeを演算する。
【００９９】
ここで、走行抵抗Frを求めるに際しては、車体速の代わりに従動輪速を用いてもかまわない。従動輪速を検出するセンサを備えていない場合は、駆動輪速を用いてもよいが、その場合は、駆動輪速が大きくなった場合にテーブル値が発散することを防止するため、リミッタを用いる。
【０１００】
図１９は第５実施形態で、第１実施形態の図８に対応する。図８と同一部分には同一のステップ番号を付けている。
【０１０１】
第５実施形態は、従動輪速の変化率dω_W2/dtの絶対値が所定値を超える過渡時にのみ、車輪速の時間的変化に対応したイナーシャトルク分のトルク補正を行うようにしたものである。
【０１０２】
図８と異なる部分を主に説明すると、ステップ1801では、
【０１０３】
【数７】
tTe＝(1/(G・Gf))×｛tTd＋J1・ω_W2・G・Gf²・(dG/dt)｝ …▲７▼
の式により基本目標エンジントルクtTe0を演算する。
【０１０４】
ここで、▲７▼式は前述の▲２▼式において、右辺第１項と右辺第３項を足し合わせたものである。
【０１０５】
ステップ1802では従動輪速の変化率dω_W2/dtの絶対値と所定値dω_WL/dtを比較する。ここで、所定値dω_WL/dtは、たとえばスロットル開度、車速等の運転条件に基づくテーブル値、マップ値などである。
【０１０６】
｜dω_W2/dt｜＞dω_WL/dtであるとき（過渡時）は、ステップ1106に進み、フラグ FSPIN ＝１のときはステップ1803で従動輪速変化率dω_W2/dtを用いて、またFSPIN＝０のときはステップ1804で駆動輪速変化率dω_W1/dtを用いてdTeを演算する。また、｜dω_W2/dt｜≦dω_WL/dtである（過渡時でない）ときはステップ1802よりステップ1805に進み、dTe＝０とする。
【０１０７】
ステップ1806では上記の基本目標エンジントルクtTe0とdTeとを足し合わせたものを目標エンジントルクtTeとして演算する。
【０１０８】
このように第５実施形態では、従動輪速の変化率dω_W2/dtの絶対値が所定値を超える過渡時にのみ、車輪速の時間的変化に対応したエンジントルクの補正を行うようにした。これによって、過渡時以外では車輪速の時間的変化に対応したトルク補正量の演算を行う必要がないので、演算負荷を抑えることができる。
【０１０９】
第５実施形態では、第１実施形態のエンジントルク補正を、従動輪速変化率dω_W2/dtの絶対値が所定値を超える過渡時にのみ行うようにしたものであるが、第２から第４の各実施形態に対しても、同様の考え方を適用することができる。
【０１１０】
実施形態では、ガソリンエンジンを用いた場合で説明したが、これに限られるものでなく、ディーゼルエンジンあるいはモータを用いる場合でも同様の効果を実現することができる。
【０１１１】
また、本発明の駆動力制御を行うことにより、駆動力の実現精度が向上するため、特にＡＳＣＤ（オートスピードコントロールデバイス）やＡＣＣ（アダプティブクルーズコントロール：前車追従車間距離制御）等での車速追従性等の性能が向上し、運転者のフィーリング感も向上する。
【図面の簡単な説明】
【図１】一実施形態の車両全体のシステム図。
【図２】PCM11の構成図。
【図３】駆動系モデルのパラメータの説明図。
【図４】数３式を用いたときの加速時の車両挙動を説明するための波形図。
【図５】数２式を用いたときの加速時の車両挙動を説明するための波形図。
【図６】低μ路で数２式を用いたときの車両挙動を説明するための波形図。
【図７】低μ路で数５式を用いたときの車両挙動を説明するための波形図。
【図８】第１実施形態の目標エンジントルクの演算を説明するためのフローチャート。
【図９】目標駆動トルクの特性図。
【図１０】ホイールスピンの有無の判定を説明するためのフローチャート。
【図１１】ホイールスピンの有無の判定を説明するためのフローチャート。
【図１２】ホイールスピンの有無の判定を説明するためのフローチャート。
【図１３】判定値dω_W1H/dtの特性図。
【図１４】判定値ω_W1Hの特性図。
【図１５】第２実施形態の目標エンジントルクの演算を説明するためのフローチャート。
【図１６】第３実施形態の目標エンジントルクの演算を説明するためのフローチャート。
【図１７】第４実施形態の目標エンジントルクの演算を説明するためのフローチャート。
【図１８】走行抵抗の特性図。
【図１９】第５実施形態の目標エンジントルクの演算を説明するためのフローチャート。
【図２０】第１、２の発明のクレーム対応図。
【図２１】第３の発明のクレーム対応図。
【図２２】第４の発明のクレーム対応図。
【符号の説明】
３ ＣＶＴ
６ 電子制御スロットル装置
11 PCM[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle driving force control device, and more particularly to control in a transient state in which a vehicle body speed and a gear ratio are changing.
[0002]
[Prior art]
In a vehicle equipped with an engine capable of controlling engine output torque independent of the driver's accelerator pedal operation and a CVT (Continuous Variable Transmission), based on the amount of accelerator pedal operation and driving conditions There is a concept of “driving force control” in which the positive and negative target driving torques calculated in this way are realized by a predetermined engine torque and a CVT gear ratio.
[0003]
In this driving force control method, the dynamic characteristics of the vehicle can be easily changed by creating the target driving torque, and the point where the engine fuel consumption rate is the smallest is used when calculating the engine torque and the CVT gear ratio. If the logic is configured, the desired target driving torque can be realized with optimum fuel efficiency.
[0004]
Here, there is inertia in the engine and CVT, and the drive torque is deviated from the target value due to this influence during CVT shift (that is, due to inertia torque corresponding to the temporal change in the gear ratio). In order to compensate, a technique is known in which a torque correction amount corresponding to a temporal change in the gear ratio is calculated, and the engine torque is corrected by this correction amount to control the drive torque so as to match the target value ( JP, 62-199536, A).
[0005]
[Problems to be solved by the invention]
However, at the time of acceleration / deceleration, not only the inertia torque corresponding to the temporal change of the gear ratio but also the inertia torque corresponding to the temporal change of the wheel speed (vehicle speed) shifts the drive torque from the target value. As described above, if the torque correction corresponding to the inertia torque corresponding to the temporal change of the gear ratio is performed, the target drive torque cannot be obtained at the time of acceleration / deceleration, and thus the vehicle behavior as intended by the driver cannot be realized.
[0006]
Therefore, in addition to the correction for the inertia torque corresponding to the temporal change of the gear ratio, the torque correction for the inertia torque corresponding to the temporal change of the wheel speed is also performed, so that the target drive torque can be reduced even during acceleration / deceleration. It is the first object of the present invention to be obtained.
[0007]
On the other hand, when the torque correction amount for the inertia torque corresponding to the temporal change of the wheel speed is obtained from the wheel speed of the driving wheel, when the wheel spin occurs on the driving wheel on a low μ road, the torque The correction works in the direction of increasing the wheel spin, which requires the driver to frequently operate the accelerator, or activates the TCS when driving force control is used in a TCS (traction control system). May increase frequency.
[0008]
  Therefore, instead of changing the wheel speed over time, the gear ratio and target driveMotionBy calculating the torque correction amount equivalent to the inertia torque corresponding to the temporal change of the wheel speed based on the torque, the target drive torque can be obtained even if wheel spin occurs in the drive wheel Is the second object of the present invention.
[0009]
[Means for Solving the Problems]
  As shown in FIG. 20, the first invention is a means 101 for calculating a target drive torque tTd of a vehicle, and a means for calculating a first correction amount of engine torque corresponding to a temporal change in the transmission gear ratio G. 102, means 103 for calculating a second correction amount of the engine torque corresponding to the temporal change of the wheel speed, and means 104 for calculating the target engine torque tTe by correcting the target drive torque tTd with these two correction amounts And means 105 for realizing the calculated target engine torque., Means for determining whether or not wheel spin is occurring on the driving wheel, and based on the determination result based on the driving wheel speed when no wheel spin is occurring and on the driven wheel speed when wheel spinning is occurring Each calculates the second correction amount.
As shown in FIG. 20, the second invention is a target drive torque for a vehicle. tTd Means to calculate 101 And the gear ratio of the transmission G Means for calculating a first correction amount of engine torque corresponding to a temporal change of 102 And means for calculating a second correction amount of the engine torque corresponding to the temporal change of the wheel speed 103 And the target drive torque with these two correction amounts. tTd Correct the target engine torque tTe Means to calculate 104 And means for realizing the calculated target engine torque 105 The second correction amount is always calculated based on the driven wheel speed.
[0010]
  First3As shown in FIG. 21, the invention includes means 101 for calculating the target drive torque tTd of the vehicle, and means 102 for calculating the first correction amount of the engine torque corresponding to the temporal change of the transmission gear ratio G. , The gear ratio G and the target driveMotionBased on the torque tTd, the means 111 for calculating the second correction amount equivalent of the engine torque corresponding to the temporal change of the wheel speed, and the target drive torque tTd is corrected by the first correction amount and the second correction amount. Means 104 for calculating the target engine torque tTe and means 105 for realizing the calculated target engine torque.
[0011]
  First4As shown in FIG. 22, the invention includes means 101 for calculating the target drive torque tTd of the vehicle, and means 102 for calculating the first correction amount of the engine torque corresponding to the temporal change of the transmission gear ratio G. , Means 103 for calculating a second correction amount of the engine torque corresponding to the temporal change of the wheel speed, the gear ratio G and the target driveMotionBased on the torque tTd, a means 111 for calculating a second correction amount equivalent to the engine torque corresponding to the temporal change in the wheel speed, a means 121 for determining whether or not wheel spin has occurred in the drive wheel, Based on the means 122 for selecting the second correction amount when the wheel spin is generated, and the second correction amount when the wheel spin is not generated, and the selected correction amount and the first correction amount. And means 123 for calculating the target engine torque tTe by correcting the target drive torque tTd and means 105 for realizing the calculated target engine torque.
[0013]
  In the fifth invention,4In the invention, the second correction amount is always calculated based on the driven wheel speed.
[0014]
  In the sixth invention,3Or4thIn the invention, the second correction amount equivalent is also calculated based on the running resistance.
[0015]
According to a seventh aspect, in the sixth aspect, the running resistance is calculated based on the driving wheel speed.
[0016]
In an eighth aspect based on the sixth aspect, the running resistance is calculated based on the driven wheel speed.
[0017]
In a ninth aspect, the running resistance is fixed to a constant value in the sixth aspect.
[0018]
  In the tenth invention,1Alternatively, in the fourth invention, the wheel spin is determined based on the driving wheel speed and the driven wheel speed.
[0019]
  In the eleventh invention,1Alternatively, in the fourth invention, the wheel spin is determined based on a change rate of the driving wheel speed.
[0020]
In a twelfth aspect of the invention, in any one of the first to eleventh aspects of the invention, the second correction amount or the second correction amount or the second correction amount is changed only when the change rate of the wheel speed (drive wheel speed or driven wheel speed) is a predetermined value or more. 2. Torque correction corresponding to 2 correction amounts is performed.
[0021]
In a thirteenth aspect of the invention, in any one of the tenth to twelfth aspects of the invention, a hysteresis characteristic is given to the determination of the presence or absence of the wheel spin.
[0022]
In a fourteenth invention, in any one of the tenth to twelfth inventions, a time difference is provided in the determination of the presence or absence of wheel spin (wheel spin is generated after a predetermined time has elapsed from when wheel spin does not actually occur. To determine that it is gone).
[0023]
【The invention's effect】
  First2According to the present invention, it is possible to compensate for the drive torque deviation that occurs due to the influence of the inertia torque corresponding to the temporal change in the wheel speed at the time of acceleration / deceleration of the vehicle. Also, the target drive torque can be realized with high accuracy.
[0024]
  First3According to the invention, it is possible to calculate the second correction amount equivalent to the engine torque corresponding to the temporal change of the wheel speed without using the temporal change of the wheel speed. The target driving torque can be realized without causing a rapid increase in the.
[0025]
  First4th,According to each of the fifth, sixth, tenth and eleventh inventions, there is no sharp increase in wheel speed even if wheel spin occurs, and when there is no wheel spin, the target drive is performed with high accuracy. Torque can be realized.
[0026]
There is a close relationship between the running resistance and the vehicle speed. In this case, according to the seventh and eighth inventions, means for detecting the vehicle speed is obtained by using the wheel speed instead of the vehicle speed. Even if it is not, an approximate running resistance can be obtained.
[0027]
According to the ninth aspect, it is possible to reduce the calculation load when calculating the second correction amount equivalent.
[0028]
According to the twelfth aspect, since the torque correction based on the second correction amount or the second correction amount is not performed except during the transition, the calculation load can be suppressed.
[0029]
According to each of the thirteenth and fourteenth aspects, frequent switching occurs between the calculation of the target engine torque when the wheel spin occurs and the calculation of the target engine torque when the wheel spin does not occur. Can be prevented.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a control system diagram of one embodiment, and FIG. 2 is a circuit configuration diagram of a control device 11.
[0031]
In FIG. 1, the output of the engine 1 is transmitted to the drive wheels 5 via the torque converter 2, CVT 3, and final gear 4.
[0032]
A so-called electronically controlled throttle device 6 that opens and closes a throttle valve 7 with a motor 8 or the like is interposed in the intake passage of the engine 1, and the amount of air taken into the engine is adjusted by the throttle valve opening, The output torque is controlled.
[0033]
A TCM (throttle control module) 9 is provided to drive the electronic control throttle device 6. In the TCM 9 to which a throttle valve opening command is transmitted from a PCM (powertrain control module) 11, the throttle valve opening command is converted into a motor drive voltage and output to the motor 8 and is detected by a throttle opening sensor. The motor drive voltage (throttle opening) is feedback-controlled so that the actual throttle valve opening matches the opening command from PCM11.
[0034]
The PCM11 is input with the accelerator operation amount (accelerator pedal depression amount) signal from the accelerator sensor, the vehicle speed signal from the vehicle speed sensor, and the select range signal from the CVT range selection lever together with the brake operation signal from the brake operation switch, etc. Then, the target drive torque is calculated based on the accelerator operation amount and the vehicle body speed, and the engine torque and the CVT gear ratio are controlled so as to obtain the target drive torque.
[0035]
The PCM 11 also performs engine control (for example, mainly control of the amount of fuel supplied to the engine and ignition timing), braking force control (brake hydraulic pressure control for each wheel to the brake actuator), and the like.
[0036]
In this way, according to the so-called driving force control system that calculates the target driving torque and controls the engine torque and the CVT gear ratio so that the target driving torque can be obtained, as described above, the target driving torque can be generated. Since it is possible to easily change the dynamic characteristics of the vehicle, when calculating the engine torque and the CVT gear ratio, if the logic is configured to use the point where the fuel consumption rate of the engine is the smallest, a desired value can be obtained. The target driving force can be achieved with optimal fuel consumption.
[0037]
This driving force control method will be described more quantitatively. Each parameter of the drive system model is taken as shown in FIG.
[0038]
[Expression 1]
Td = F × R… ▲ 1 ▼
Where F: Driving force
R: Tire effective radius
When the vehicle drive torque Td is defined by the following equation, it can be seen that the target engine torque tTe of the following equation can be realized in order to make the actual drive torque Td coincide with the target drive torque tTd.
[0039]
[Expression 2]

However, G: CVT gear ratio
Gf: Final gear reduction ratio
J1: Moment of inertia on the input side of the engine and CVT
J2: Moment of inertia from CVT output to final gear input
J3: Moment of inertia from final gear to drive wheel
ω_W: Angular speed of wheel
Note that dω in the second term in parentheses on the right side of equation (2)_W/ dt is the angular velocity ω_WThe rate of change of the wheel speed V_WRate of change dV_WdV between / dt_W/ dt = R ・ dω_WSince there is a / dt relationship, the difference is only R as a proportionality constant, and the wheel speed is often used rather than the angular speed, so_WThe wheel speed, dω_W/ dt is the rate of change of wheel speed. Also, when distinguishing between driving wheels and driven wheels,_W1 is the driving wheel speed, dω_W1 / dt is the rate of change in driving wheel speed, and ω_W2 is driven wheel speed, dω_W2 / dt is the change rate of the driven wheel speed.
[0040]
Here, the third term in parentheses on the right side of the formula (2) is the correction amount corresponding to the inertia torque corresponding to the temporal change in the gear ratio (proportional to the change rate dG / dt of the gear ratio). Corresponding to changes in wheel speed over time (change rate of wheel speed dω_WThis is the correction amount for the inertia torque (proportional to / dt).
[0041]
In equation (2), gear ratio G and wheel speed ω_WCan be used to calculate the torque correction amounts of the second and third terms in parentheses on the right side of equation (2) using these and the vehicle specification values (Gf, J1, J2, J3). The target engine torque tTe can be obtained by correcting the target drive torque tTd of the first term in the right parenthesis with these torque correction amounts.
[0042]
However, in the conventional apparatus, the following equation in which the second term in the right parenthesis of equation (2) is omitted:
[0043]
[Equation 3]
tTe = (1 / (G ・ Gf)) × {tTd + J1 ・ ω_W・ G ・ Gf²・ (DG / dt)}… ▲ 3 ▼
Was used to calculate the target engine torque tTe. In other words, in the past, correction was made only for the inertia torque corresponding to the temporal change in the gear ratio, so the target drive torque could not be obtained during acceleration / deceleration, and the vehicle behavior as intended by the driver could not be realized. .
[0044]
In order to cope with this, in the present invention, the target engine torque is calculated by the above equation (2), so that even if the inertia torque corresponding to the temporal change of the wheel speed during acceleration / deceleration is affected, Make sure that there is no deviation. For example, when the target engine torque is calculated using the equation (3) when the acceleration operation is performed, the target drive torque is obtained while the vehicle speed is changing as shown in FIG. On the other hand, when the target engine torque is calculated using equation (2) under the same conditions as in FIG. 4, the target drive torque can be accurately achieved while the vehicle speed is changing as shown in FIG. It becomes possible to do.
[0045]
However, when the above equation (2) is used, the wheel speed change rate dω is added to the second term in the right parenthesis (the correction amount for the inertia torque corresponding to the temporal change of the wheel speed)._W/ dt is included, and if wheel spin is detected on the drive wheel when the wheel speed is detected, the wheel speed (engine rotation) increases rapidly due to the effect of the second term. there is a possibility.
[0046]
Assuming that there is no wheel spin on the drive wheels,
[0047]
[Expression 4]
(F−Fr) / M = R ・ (dω_W/ dt)… ▲ 4 ▼
Where F: Driving force
Fr: Running resistance
M: Vehicle mass
R: Tire effective radius
Holds.
[0048]
Here, assuming that the engine delay is very small, using equation (4) to transform equation (2),
[0049]
[Equation 5]

Transformed into
[0050]
However, the coefficient α of the second term in the parentheses on the right side of equation (5) is
[0051]
[Formula 6]
α = (J1 ・ G²・ Gf²+ J2 ・ Gf²+ J3) / (M ・ R²)… ▲ 6 ▼
(Value determined by G and vehicle specifications).
[0052]
  thisNumber 5The second term in the right parenthesis of the expressionof( tTd − Fr ・ R ) ・ Α (equivalent to the second correction amount)Is the wheel speed change rate dω_WBecause / dt is not included explicitly,Number 2There is no possibility that the wheel speed (engine rotation) suddenly increases as in the case of using the equation. Therefore,Number 5Using the formula, the target drive torque can be accurately achieved when no wheel spin occurs, and it is possible to prevent the wheel speed (engine rotation) from rapidly increasing even on a low μ road that generates wheel spin. .
[0053]
For example, when the acceleration operation is performed on the low μ road under the same conditions as in FIGS. 4 and 5, the target engine torque is calculated using the formula (2) as shown in FIGS. 6 and 7. In some cases, as shown in FIG. 6, once a wheel spin occurs, a phenomenon occurs in which only the driving wheel speed increases without realizing the desired value of the driving torque. On the other hand, when the target engine torque is calculated using the equation (5), it becomes as shown in FIG. 7, and it is possible to prevent the drive wheel speed from increasing even if wheel spin occurs. Compared to when no wheel spin occurs (see FIG. 5), although the accuracy is slightly reduced, the drive torque can also substantially achieve the target value.
[0054]
Thus, in the present invention, when the target engine torque is calculated using the formula (2) or formula (5), whether the wheel speed of the driving wheel or the wheel speed of the driven wheel is used as the wheel speed. Considering the above, the following five embodiments can be considered.
[0055]
<1> The target engine torque is calculated by equation (2) using the driving wheel speed when no wheel spin occurs, and by equation (2) using the driven wheel speed when wheel spin occurs.
[0056]
<2> Regardless of the presence or absence of wheel spin, the target engine torque is always calculated using equation (2) using the driven wheel speed.
[0057]
<3> Regardless of whether wheel spin is present or not, the target engine torque is calculated by equation (5).
[0058]
<4> When wheel spin is not generated, the target drive torque can be achieved with higher accuracy in equation (2) than in equation (5). Therefore, when wheel spin is not generated, use equation (2) When a wheel spin occurs, the target engine torque is calculated using equation (5).
[0059]
<5> A correction amount for the inertia torque corresponding to the temporal change of the wheel speed only during acceleration / deceleration (the second term in the right parenthesis of the equations (2) and (5)) is calculated.
[0060]
When the formula (5) is used in the above <3> and <4>, the running resistance Fr is required for the calculation of the second term in the parentheses on the right side of the formula (5). In this case, there is generally a relationship as shown in FIG. 18 described later between the vehicle speed and the running resistance Fr. Therefore, if the data of FIG. 18 is provided as a table value in the program, the running resistance Fr is determined from the vehicle speed. Can be requested. The approximate value of the running resistance Fr can also be calculated by using the driven wheel speed or the driving wheel speed instead of the vehicle body speed. Further, in the second term in the parenthesis on the right side of the equation (5), if the term of the running resistance Fr (Fr · R) is very small with respect to the target drive torque tTd, a constant value or this term is always set regardless of the driving conditions. It may be ignored (corresponding to Fr = 0).
[0061]
In the above <1>, <4>, and <5>, the calculation formula of the target engine torque must be switched between when the wheel spin is generated and when it is not generated. It is necessary to prevent this from occurring.
[0062]
Hereinafter, a specific description will be given using a flowchart.
[0063]
  Note that FIGS. 8, 15, 16, and 16 described later correspond to the order of <1> to <5> above.17Each flowchart of FIG. 19 is assembled.
[0064]
The flowchart in FIG. 8 is executed every 10 ms in the first embodiment.
[0065]
In step 1101, the accelerator operation amount APS detected by the throttle sensor, the vehicle speed V detected by the vehicle speed sensor_VThe driving wheel speed ω detected by the driving wheel speed sensor (see FIG. 2)_W1. Driven wheel speed ω detected by a driven wheel speed sensor (see FIG. 2)_W2. Read the actual gear ratio of CVT (calculated based on drive wheel speed and CVT input shaft speed) G.
[0066]
Of these, accelerator operation amount APS and vehicle speed V_VFrom step 1102, a map having the contents shown in FIG. 9 is searched to obtain the target drive torque tTd.
[0067]
In step 1103, the change rate dG / dt is calculated from the actual gear ratio G. This value may be calculated using the target speed ratio of the speed change control.
[0068]
In steps 1104 and 1105, the driving wheel speed ω_W1 to its rate of change dω_W1 / dt, driven wheel speed ω_W2 to the rate of change dω_WCalculate 2 / dt respectively.
[0069]
  In step 1106, the flag FSPIN is checked. This flag FSPIN indicates that wheel spin is occurring when FSPIN = 1, and FSPIN =0This means that no wheel spin has occurred. The setting of this flag (determination of the presence or absence of wheel spin) will be described with reference to the flowcharts of FIGS.
[0070]
The flow of FIGS. 10 to 12 is executed every 10 ms independently of the flow of FIG.
[0071]
First, referring to FIG. 10, in steps 1201 and 1202, the driving wheel speed ω_W1And driven wheel speed ω_W2, And the speed difference dω (= ω_W1-ω_W2) is calculated in step 1203.
[0072]
Steps 1204 to 1206 are determination portions for determining whether or not there is a wheel spin with hysteresis. When the speed difference dω exceeds the first determination value dωH, it is determined that wheel spin has occurred, and the speed difference dω is greater than the first determination value dωH. When the value falls below the small second determination value dωL, it is determined that no wheel spin has occurred.
[0073]
Specifically, in step 1204, the flag FSPIN (initial setting to “0”) is checked. If it is the initial setting state, the process proceeds to step 1205 from FSPIN = 0, and the speed difference dω is compared with the first determination value dωH. When dω> dωH, it is determined that wheel spin has occurred, and the process proceeds to step 1207 to set FSPIN = 1 and terminate the current process.
[0074]
From FSPIN = 1, the process proceeds from step 1204 to step 1206, and this time, the speed difference dω is compared with the second determination value dωL. Here, the second determination value dωL is smaller than the first determination value dωH. If dω ≧ dωL, the processing of step 1207 is performed (that is, the value of the flag is kept as it is), and the current processing is terminated. When dω is less than dωL, it is determined that no wheel spin has occurred, and the process proceeds from step 1206 to step 1208 to set FSPIN = 0.
[0075]
The two determination values dωH and dωL may be constants, table values based on operating conditions such as throttle opening, vehicle speed, or map values.
[0076]
Thus, by providing hysteresis for switching the flag FSPIN from “0” to “1” or vice versa, the occurrence of hunting can be prevented.
[0077]
In the flow of FIG. 10, the occurrence of hunting is prevented by hysteresis, whereas in the flow of FIG. 11, the flag FSPIN is changed from “1” to “0” after a lapse of a predetermined time from when wheel spin does not actually occur. By switching to, the occurrence of hunting is prevented.
[0078]
The same parts as those in FIG. 10 are given the same step numbers, and the description will focus on the parts different from those in FIG.
[0079]
If the speed difference dω is larger than the determination value dωH in step 1205, the process proceeds to step 1207 to set the flag FSPIN = 1, and then in step 1301, the counter T is reset to 0 and the current process is terminated.
[0080]
When the speed difference dω is equal to or less than dωH, it is determined that no wheel spin occurs, and the process proceeds from step 1205 to step 1302 where the counter T is compared with the predetermined value T0. Here, the predetermined value T0 is a value that determines the elapsed time. T0 may be a constant, a table value based on operating conditions such as throttle opening, vehicle speed, or a map value.
[0081]
If the counter T is equal to or smaller than the predetermined value T0, the process proceeds to steps 1303 and 1304, the flag FSPIN = 1 is set, the counter T is incremented by 1, and the current process is terminated.
[0082]
dω ≦ dω_HIn this state, the increment of step 1304 is repeated, and eventually T> T0 (that is, when a predetermined time T0 has elapsed since no wheel spin occurs), the process proceeds to step 1208 and the flag FSPIN = 0 is set.
[0083]
10 and 11, the driving wheel speed ω_W1 and driven wheel speed ω_WAlthough the configuration in which the presence / absence of wheel spin is determined based on the speed difference dω of 2 is not limited thereto, the configuration in which the presence / absence of wheel spin is determined based on the ratio between the two wheel speeds may be used.
[0084]
The flow of FIG. 12 is for determining the presence or absence of wheel spin based on the rate of change of the driving wheel speed. The same step numbers are assigned to the same parts as in FIG.
[0085]
In the initial setting state, since FSPIN = 0, the process proceeds from step 1204 to step 1401, and the driving wheel speed ω_W1 to its rate of change dω_WCalculate 1 / dt, and this rate of change dω_W1 / dt and judgment value dω_W1H / dt is compared in step 1402.
[0086]
dω_W1 / dt ≦ dω_WIf 1H / dt, no wheel spin has occurred, so the process proceeds from step 1402 to step 1403, where the flag FSPIN = 0 and the current process is terminated. dω_W1 / dt> dω_WWhen 1H / dt is reached, it is determined that wheel spin has occurred, and the process proceeds from step 1402 to step 1207, where FSPIN = 1 is set and the current process is terminated.
[0087]
On the other hand, when FSPIN = 1, the routine proceeds from step 1204 to 1404, where the driving wheel speed ω_W1 and judgment value ω_WCompare 1H.
[0088]
Driving wheel speed ω_W1 is the judgment value ω_WIf it exceeds 1H, it is determined that a slip is still occurring, and the flag FSPIN = 1 is set in step 1207, and the current process is terminated. Eventually, ω_W1 ≦ ω_WIf it becomes 1H, it is determined that the slip has stopped, and the process proceeds from step 1404 to step 1208, where FSPIN = 0 and the current process is terminated.
[0089]
Above judgment value dω_W1H / dt and ω_W1H is, for example, a table value or a map value based on operating conditions such as throttle opening, vehicle speed, and the like. Judgment value dω_WAn example of a 1H / dt map is shown in FIG._WAn example of the 1H map is shown in FIG.
[0090]
As described above, the three methods for setting the flag FSPIN have been described with reference to FIGS. 10 to 12, but any of them may be used.
[0091]
Returning to FIG. 8, when the flag FSPIN = 0 (no wheel spin is generated), the process proceeds to step 1108, and the driving wheel speed change rate dω_WUsing 1 / dt, the target engine torque tTe is calculated according to the above equation (2). On the other hand, when FSPIN = 1 (wheel spin is occurring), the routine proceeds to step 1107, where the driven wheel speed change rate dω_WUsing 2 / dt, the target engine torque tTe is calculated by the above equation (2).
[0092]
As described above, in the first embodiment, the above-described equation (2) is used for calculating the target engine torque, and the wheel speed change rate used for the calculation is switched depending on the presence or absence of the wheel spin. A rapid increase in speed does not occur, and when no wheel spin occurs, the target drive torque can be realized with high accuracy.
[0093]
FIG. 15 shows a second embodiment corresponding to FIG. 8 of the first embodiment. The same steps as those in FIG. 8 are given the same step numbers.
[0094]
In the second embodiment, the change rate dω of the driven wheel speed is always irrespective of the presence or absence of wheel spin._WThe target engine torque tTe is calculated by the above equation (2) using 2 / dt, and this embodiment also provides the same operational effects as the first embodiment.
[0095]
Since each step is the same as that in FIG. 8 of the first embodiment except that the switching by the flag FSPIN is eliminated, detailed description thereof is omitted.
[0096]
FIG. 16 shows a third embodiment, and FIG. 17 shows a fourth embodiment, which corresponds to FIG. 8 of the first embodiment. The same steps as those in FIG. 8 are given the same step numbers.
[0097]
The third embodiment of FIG. 16 calculates the target engine torque tTe by the above-described equation (5) regardless of the presence or absence of wheel spin, and the fourth embodiment of FIG. 17 has no wheel spin. The target engine torque is calculated based on the above equation (2) and when the wheel spin is generated based on the above equation (5). The same effect as 1 embodiment arises.
[0098]
16 and 17, the difference from FIG. 8 will be mainly described. In step 1601, the coefficient α is calculated by the above equation (6) using the gear ratio G, and in step 1602, the vehicle speed V_V18 is searched to obtain the running resistance Fr. In step 1603, the target engine torque tTe is calculated by the above equation (5) using the coefficient α and the running resistance Fr.
[0099]
Here, when determining the running resistance Fr, the driven wheel speed may be used instead of the vehicle body speed. If the sensor for detecting the driven wheel speed is not provided, the driving wheel speed may be used, but in that case, a limiter is used to prevent the table value from diverging when the driving wheel speed increases. Use.
[0100]
FIG. 19 shows a fifth embodiment corresponding to FIG. 8 of the first embodiment. The same steps as those in FIG. 8 are given the same step numbers.
[0101]
In the fifth embodiment, the change rate dω of the driven wheel speed_WOnly when the absolute value of 2 / dt exceeds a predetermined value, torque correction for the inertia torque corresponding to the temporal change of the wheel speed is performed.
[0102]
The difference from FIG. 8 will be mainly described. In step 1801,
[0103]
[Expression 7]
tTe = (1 / (G ・ Gf)) × {tTd + J1 ・ ω_W2 ・ G ・ Gf²・ (DG / dt)}… ▲ 7 ▼
The basic target engine torque tTe0 is calculated by the following formula.
[0104]
Here, Equation (7) is the sum of the first term on the right side and the third term on the right side in Equation (2) above.
[0105]
In step 1802, the change rate of the driven wheel speed dω_WAbsolute value of 2 / dt and predetermined value dω_WCompare L / dt. Where the predetermined value dω_WL / dt is, for example, a table value or a map value based on operating conditions such as throttle opening and vehicle speed.
[0106]
  ｜ dω_W2 / dt ｜ ＞ dω_WIf L / dt (transient), go to step 1106 toG FSPIN = 1In step 1803, the driven wheel speed change rate dω_WWhen 2 / dt is used and FSPIN = 0, in step 1804, the driving wheel speed change rate dω_WCalculate dTe using 1 / dtTo do. Also, | Dω_W2 / dt | ≦ dω_WWhen it is L / dt (not during transition), the routine proceeds from step 1802 to step 1805, where dTe = 0 is set.
[0107]
In step 1806, the sum of the basic target engine torque tTe0 and dTe is calculated as the target engine torque tTe.
[0108]
Thus, in the fifth embodiment, the change rate dω of the driven wheel speed_WOnly when the absolute value of 2 / dt exceeds the predetermined value, the engine torque is corrected in accordance with the temporal change of the wheel speed. As a result, it is not necessary to calculate the torque correction amount corresponding to the temporal change of the wheel speed except during the transition, and the calculation load can be suppressed.
[0109]
In the fifth embodiment, the engine torque correction of the first embodiment is performed using the driven wheel speed change rate dω._WAlthough this is performed only at the time of transition in which the absolute value of 2 / dt exceeds a predetermined value, the same concept can be applied to the second to fourth embodiments.
[0110]
In the embodiment, the case where a gasoline engine is used has been described. However, the present invention is not limited to this, and the same effect can be realized even when a diesel engine or a motor is used.
[0111]
In addition, since the driving force control accuracy of the present invention is improved by the driving force control according to the present invention, the vehicle speed tracking particularly in ASCD (automatic speed control device), ACC (adaptive cruise control: front vehicle tracking inter-vehicle distance control), etc. The performance such as the performance is improved, and the feeling of feeling of the driver is also improved.
[Brief description of the drawings]
FIG. 1 is a system diagram of an entire vehicle according to an embodiment.
FIG. 2 is a configuration diagram of PCM11.
FIG. 3 is an explanatory diagram of parameters of a drive system model.
[Fig. 4]Number 3The wave form diagram for demonstrating the vehicle behavior at the time of acceleration when using a type | formula.
[Figure 5]Number 2The wave form diagram for demonstrating the vehicle behavior at the time of acceleration when using a type | formula.
[Figure 6] On a low μ roadNumber 2The wave form diagram for demonstrating a vehicle behavior when using a type | formula.
[Fig. 7] On a low μ roadNumber 5The wave form diagram for demonstrating a vehicle behavior when using a type | formula.
FIG. 8 is a flowchart for explaining calculation of a target engine torque according to the first embodiment.
FIG. 9 is a characteristic diagram of target drive torque.
FIG. 10 is a flowchart for explaining determination of presence / absence of wheel spin.
FIG. 11 is a flowchart for explaining determination of presence / absence of wheel spin.
FIG. 12 is a flowchart for explaining determination of the presence or absence of wheel spin.
FIG. 13: judgment value dω_W1H / dt characteristic diagram.
FIG. 14: judgment value ω_W1H characteristic diagram.
FIG. 15 is a flowchart for explaining calculation of a target engine torque according to the second embodiment.
FIG. 16 is a flowchart for explaining calculation of a target engine torque according to the third embodiment.
FIG. 17 is a flowchart for explaining calculation of a target engine torque according to the fourth embodiment.
FIG. 18 is a characteristic diagram of running resistance.
FIG. 19 is a flowchart for explaining calculation of a target engine torque according to the fifth embodiment.
FIG. 20 shows the first2FIG.
FIG. 213FIG.
FIG. 224FIG.
[Explanation of symbols]
  3 CVT
  6 Electronically controlled throttle device
  11 PCM

Claims (14)

Means for calculating a target driving torque of the vehicle;
Means for calculating a first correction amount of engine torque corresponding to a temporal change in a transmission gear ratio;
Means for calculating a second correction amount of engine torque corresponding to a temporal change in wheel speed;
Means for correcting the target drive torque with these two correction amounts to calculate the target engine torque;
Means for realizing the calculated target engine torque , and
Means for determining whether wheel spin is occurring in the drive wheel;
Based on the determination result, the second correction amount is calculated based on the driving wheel speed when no wheel spin occurs, and based on the driven wheel speed when wheel spin occurs. Force control device.   Means for calculating a target driving torque of the vehicle;
  Means for calculating a first correction amount of engine torque corresponding to a temporal change in a transmission gear ratio;
  Means for calculating a second correction amount of engine torque corresponding to a temporal change in wheel speed;
  Means for correcting the target drive torque with these two correction amounts to calculate the target engine torque;
  Means for realizing the calculated target engine torque;
  With
  The second correction amount is always calculated based on the driven wheel speed.
  A driving force control apparatus for a vehicle. Means for calculating a target driving torque of the vehicle;
Means for calculating a first correction amount of engine torque corresponding to a temporal change in a transmission gear ratio;
Means for calculating a second correction amount equivalent engine torque corresponding to the temporal change of the wheel speed based on the target drive Doto torque and the gear ratio,
Means for calculating the target engine torque by correcting the target drive torque with the first correction amount and the second correction amount;
A vehicle driving force control apparatus comprising: means for realizing the calculated target engine torque. Means for calculating a target driving torque of the vehicle;
Means for calculating a first correction amount of engine torque corresponding to a temporal change in a transmission gear ratio;
Means for calculating a second correction amount of engine torque corresponding to a temporal change in wheel speed;
Means for calculating a second correction amount equivalent engine torque corresponding to the temporal change of the wheel speed based on the target drive Doto torque and the gear ratio,
Means for determining whether wheel spin is occurring in the drive wheel;
Means for selecting the second correction amount when wheel spin occurs based on the determination result, and selecting the second correction amount when wheel spin does not occur;
Means for correcting the target drive torque with the selected correction amount and the first correction amount to calculate a target engine torque;
A vehicle driving force control apparatus comprising: means for realizing the calculated target engine torque. The vehicular driving force control apparatus according to claim 4 , wherein the second correction amount is always calculated based on a driven wheel speed. The vehicular driving force control apparatus according to claim 3 or 4 , wherein the second correction amount equivalent is calculated based on a running resistance.   The vehicle driving force control device according to claim 6, wherein the running resistance is calculated based on a driving wheel speed.   The vehicle driving force control device according to claim 6, wherein the running resistance is calculated based on a driven wheel speed.   The vehicle driving force control device according to claim 6, wherein the running resistance is fixed to a constant value. The vehicle driving force control apparatus according to claim 1 or 4, wherein the determining based on said wheel spin drive wheel speed and the driven wheel speed. The vehicle driving force control apparatus according to claim 1 or 4, wherein the determining based on said wheel spin on the change rate of the drive wheel speed.   12. The torque correction according to any one of claims 1 to 11, wherein the torque correction based on the second correction amount or the second correction amount is performed only during a transition in which a rate of change in wheel speed is equal to or greater than a predetermined value. Vehicle driving force control device.   The vehicle driving force control device according to any one of claims 10 to 12, wherein a hysteresis characteristic is given to the determination of the presence or absence of the wheel spin.   The vehicle driving force control device according to any one of claims 10 to 12, wherein a time difference is provided in the determination of the presence or absence of the wheel spin.

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