JP3786082B2 - Control device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a hybrid vehicle that improves fuel consumption. <P>SOLUTION: In the controller device for a hybrid vehicle which is provided with an engine and a motor as drive control sources, and a battery that feeds and receives power between the motor and the battery, when the distance to a destination is shorter than a prescribed value, a position far from the destination is set as a virtual destination, a target charging state at the virtual destination when traveling to the virtual destination from a present position is set, and when the distance to a destination is below a prescribed value, the target charging state at the virtual destination is set so as to reduce fuel consumption to the virtual destination. Based on a vehicle speed, a drive control command value and a charging state, drive points of the engine, and the motor are determined so as to be in the set target charging states. <P>COPYRIGHT: (C)2004,JPO

Description

【００３８】
に低減して再計算する。逆に、目的地における予測ＳＯＣ(ｐ＿ＳＯＣ(ｎ))が目的地におけるｔ＿ＳＯＣより小さい場合は、ＳＯＣｃを、
【００３９】
【数２】

【００４０】
に増加して再計算する。
【００４１】
以上の演算を、目的地における予測ＳＯＣ（ｐ＿ＳＯＣ(ｎ))が目的地におけるｔ＿ＳＯＣとほぼ一致するまで、つまり両者の差が所定値以下になるまで繰り返し、両者がほぼ一致した場合のＳＯＣｃ＿ｊ（ｊは０以上の整数）を最終的なＳＯＣ換算指標ＳＯＣｃに決定する。この演算は、目的地の新規入力または変更、誘導経路の逸脱、あるいは渋滞状況の変化があった際に行われる。
【００４２】
ここで、αは、繰り返し演算が発散しない程度の固定値とする。あるいは、ＳＯＣｃ＿０としては、交通情報などに応じて決定してもよい。例えば、渋滞が激しい場合、現在のＳＯＣ(ｄ＿ＳＯＣ)が小さい場合はＳＯＣｃ＿０を小さめの値とする。あるいは以前に走行したことがある経路の場合は、そのときのＳＯＣｃに基づいて現在のＳＯＣ(ｄ＿ＳＯＣ)が小さいほど小さめに補正した値を初期値とする。
【００４３】
《エンジン／モーターの運転点決定方法》
次に、図４および図５により、クラッチ締結時のエンジン／モーター運転点の決定方法を説明する。なお、図４の運転点Ａ、Ｎ、Ｂ、Ｃ、Ｄ、Ｅは図５の運転点Ａ、Ｎ、Ｂ、Ｃ、Ｄ、Ｅにそれぞれ対応する。
【００４４】
ＳＯＣ換算指標ＳＯＣｃを決定するための演算を行っているときには、仮設定中のＳＯＣｃと、各分割区間ｗａｙ(ｉ)ごとの予測車速ｐ＿Ｖｓｐ(ｉ)および予測制駆動力指令値ｐ＿ｔＴｄ(ｉ)とに基づいて、エンジン２およびモーター１、４の仮の運転点を決定する。また一方、ＳＯＣｃの決定が終了し、実際に目的地へ向かって走行しているときには、決定したＳＯＣｃ（＝ＳＯＣｃ＿ｊ）と、車速検出値ｄ＿Ｖｓｐと、制駆動力指令値の演算値ｄ＿ｔＴｄとに基づいて、エンジン２およびモーター１、４の走行時の正式な運転点を決定する。なお、制駆動力指令値の演算値ｄ＿ｔＴｄは、車速検出値ｄ＿Ｖｓｐとアクセル開度検出値とに基づいて予め設定した制駆動力指令値テーブルから表引き演算して求める。
【００４５】
いずれの運転点決定時においても、ＳＯＣｃ＿ｊまたはＳＯＣｃが大きいほどバッテリー充電時の燃料利用効率が高くなる場合にだけ充電を行うように運転点を決定する。
【００４６】
図４は車速５０ｋｍ／ｈ、制駆動力指令値１０００Ｎのときのエンジン／モーター運転点を示し、図５は同一の車速および制駆動力指令値におけるエンジン／モーター運転点とバッテリー充電量との関係を示す。
【００４７】
図４において、太線は同一エンジン出力を得る場合に燃料消費量が最少となる運転点を結んでできる最適燃費線であり、エンジン２、モーター１、４、無段変速機５の効率を考慮したものとなっている。エンジン／モーター運転点は、必ずこの太線上に定められる。点Ａは、できる限りモーター１、４で車両を駆動（例えばメインバッテリー１５から取り出せる最大の電力をモーター１、４へ供給して車両を駆動）し、不足分をエンジン２の出力でまかなう場合の運転点である。一方、点Ｅは、バッテリー１５の充電量を多くするためにエンジン２で車両を駆動するとともにモーター１、４を駆動して発電させる場合の運転点である。
【００４８】
今、メインバッテリー１５が放電している運転点Ａにおいて、エンジン２への燃料供給量を増加していくと点Ｎでメインバッテリー１５の充放電量が０となり、さらに点Ｂ→Ｃ→Ｄ→Ｅの順にメインバッテリー１５の充電量が増加していく。ちなみに、図５に示すように、点Ｂにおける充電量はｃ＿ｂ［ｋＷ］、点Ｃにおける充電量はｃ＿ｃ［ｋＷ］、点Ｄにおける充電量はｃ＿ｄ［ｋＷ］、点Ｅにおける充電量はｃ＿ｅ［ｋＷ］である。
【００４９】
点Ａにおける燃料供給量を基準として、燃料増加量Δｆｕｅｌに対する充電電力増加量Δｂａｔと充電電力Ｂａｔの関係を図５の曲線▲１▼に示す。また、曲線▲１▼から燃料増加量Δｆｕｅｌに対する充電電力増加量Δｂａｔの比（＝Δｂａｔ／Δｆｕｅｌ）を求めたものが曲線▲２▼であり、この明細書ではこの比を感度Ｓと呼ぶ。なお、これらの曲線▲１▼、▲２▼は予め実験などにより車速と制駆動力の条件ごとに求めておく。
【００５０】
図５に示すように、ＳＯＣ換算指標が大きいほど大きな感度Ｓに対応づける。この例では、ＳＯＣ換算指標＝７０％に対して感度Ｓをｓ１７０に、ＳＯＣ換算指標＝５０％に対して感度Ｓをｓ１５０に、ＳＯＣ換算指標＝３０％に対して感度Ｓをｓ１３０にそれぞれ設定している。
【００５１】
そして、ＳＯＣ換算指標に応じた感度Ｓの充電電力Ｂａｔを実現するエンジン／モーター運転点を演算する。例えば、ＳＯＣ換算指標が７０％の場合には、感度曲線▲２▼上の感度Ｓ＝ｓ１７０を満たす点Ｂ１を求め、さらに感度ｓ１７０を実現する燃料供給量の曲線▲１▼上の点Ｂを求め、この点Ｂに対応する図４の点Ｂをエンジン２およびモーター１、４の運転点とすればよい。なお、感度Ｓを満たす曲線▲２▼上の点が２個ある場合は、充電電力Ｂａｔが多い点を採用する。また、感度Ｓを満たす点が曲線▲２▼上にない場合、すなわち感度Ｓで充電を行うことができる運転点が今現在の車速と制駆動力の条件下では存在しない場合、図４の点Ａをエンジン２およびモーター１、４の運転点とする。
【００５２】
曲線▲１▼、▲２▼は、車速と制駆動力の条件ごとに異なるので、感度Ｓの最高値も車速と制駆動力の条件ごとに異なる。よって、ＳＯＣ換算指標が大きい場合は、限られた車速と制駆動力の条件下でのみ、感度Ｓを満たす運転点を取ることができる。反対にＳＯＣ換算指標が小さい場合は、広い範囲の車速と制駆動力の条件下で感度Ｓを満たす運転点を取ることができる。
【００５３】
これにより、ＳＯＣ換算指標が大きいほど、バッテリー１５への充電を行う機会が少なくなり、反対にＳＯＣ換算指標が小さいほど充電の機会は多くなる。また、ＳＯＣ換算指標が大きいほど充電実行時の燃料利用効率が高くなり、反対にＳＯＣ換算指標が小さいほど充電実行時の燃料利用効率が低くなる。
【００５４】
なお、以上の説明では、ＳＯＣ換算指標に応じた感度Ｓを求め、さらに感度Ｓを実現する充電電力Ｂａｔを求め、充電電力Ｂａｔに対応するエンジン／モーター運転点を求める例を示したが、ＳＯＣ換算指標に対する充電電力Ｂａｔおよびエンジン／モーター運転点を関連付けたデータを記憶しておき、そのデータを読み出して充電電力Ｂａｔおよびエンジン／モーター運転点を求めるようにしてもよい。これにより、エンジン／モーター運転点の演算を容易にできる。
【００５５】
また、図５の特性曲線▲１▼については、電装品の消費電力を考慮した上で、点Ｎより左側の放電時についてはメインバッテリー１５の放電効率を、点Ｎより右側の充電時についてはメインバッテリー１５の充電効率を考慮して関連づけるとよい。
【００５６】
無段変速機５の変速比は、車速とエンジン／モーター運転点の回転速度を実現する変速比に調整する。さらに、モーター１と４のトルクは、予め設定した配分にし、モーター１、４とエンジン２により目標制駆動力指令値を実現できる値を演算する。
【００５７】
クラッチ３の動作点は予め図６に示すように関係づけておき、この関係にしたがって締結と解放を制御する。クラッチ解放時は、エンジン２とモーター１の回転速度が一致し、定常的にはエンジン２のトルクと、モーター１のトルクのエンジン軸回り換算値とが等しいという条件のもとに、図４および図５により説明した方法によりエンジン２およびモーター１、４の運転点を決定する。
【００５８】
この実施の形態では、ＳＯＣ換算指標の演算には上述したエンジンとモーターの運転点決定方法を用いており、逆に、エンジンとモーターの運転点の決定には上述したＳＯＣ換算指標を用いるため、いずれか一方を先に決定しないとどちらも演算できないことになる。そこで上述したように、ＳＯＣ換算指標ＳＯＣｃの演算において、まずＳＯＣｃの値に何らかの値、上記例では初期値ＳＯＣｃ＿０を設定してエンジンとモーターの仮の運転点を求め、さらに目的地におけるＳＯＣ（ｐ＿ＳＯＣ（ｎ））を予測する。そして、所定値αを用いて数式１と数式２により、目的地における予測ＳＯＣ（ｐ＿ＳＯＣ（ｎ））が目標ＳＯＣ（ｔ＿ＳＯＣ）と一致するまでＳＯＣ換算指標ＳＯＣｃの演算を繰り返し、演算が収束したときのＳＯＣｃ＿ｊを最終的なＳＯＣ換算指標ＳＯＣｃに決定する。
【００５９】
そして、決定したＳＯＣ換算指標ＳＯＣｃに基づいてエンジンとモーターの実際の運転点を決定する。まず、車速とアクセル開度とに基づいて予め設定した制駆動力指令値のテーブルから、検出車速ｄ＿Ｖｓｐと検出アクセル開度ｄ＿Ａｃｃに対応する制駆動力指令値ｄ＿ｔＴｄを表引き演算する。次に、ＳＯＣ換算指標ＳＯＣｃと、車速検出値ｄ＿Ｖｓｐと、制駆動力指令値の演算値ｄ＿ｔＴｄとに基づいて、エンジンとモーターの走行時の正式な運転点を決定する。そして、この運転点でエンジン２とモーター１、４を制御する。
【００６０】
これにより、目的地までの誘導経路において、ＳＯＣ換算指標ＳＯＣｃを用いてエンジン２とモーター１、４の運転点が決定されることになり、目的地までの誘導経路における燃料消費量を最少限に抑制しながら、目的地におけるメインバッテリー１５のＳＯＣをその目標値ｔ＿ＳＯＣにすることができる。
【００６１】
図７および図８は車両制御プログラムを示すフローチャートであり、これらのフローチャートにより第１の実施の形態の動作を説明する。車両コントローラー１６は所定時間ごとにこの制御プログラムを実行する。ステップ１において現在地を検出する。なお、２回目以降の実行時には分割区間ｗａｙ（ｉ)（ｉ＝１〜ｎ）のどの位置にいるかも検出する。続くステップ２で、目的地の新規入力または変更、誘導経路の逸脱、あるいは渋滞状況の変化があったかどうかを確認し、いずれかがあったときはステップ３へ進み、何もなかったときはステップ１１へ進む。なお、渋滞状況の変化はＶＩＣＳなどの路車間通信装置により入手する。
【００６２】
目的地の新規入力または変更、誘導経路の逸脱、渋滞状況の変化のいずれかがあったときは、ステップ３で目的地までの誘導経路を探索する。続くステップ４で、目的地までの誘導経路をｎ区間ｗａｙ（ｉ）（ｉ＝１〜ｎ）に分割する。この経路分割方法には、勾配変化地点、交差点、道路種別変化地点、渋滞開始地点、渋滞終了地点、高速道路の料金所など、道路環境の内の特徴のある地点を区分点として区分する方法や、目的地までの距離をｎ等分して区分する方法などがある。
【００６３】
なお、目的地までの距離が遠い場合には、目的地までの誘導経路上の通過点を仮想目的地として経路分割を行ってもよい。一方、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合には、現在地からの距離が所定距離の目的地を通る略延長線上の地点を仮想目的地と設定し、目的地と仮想目的地の道路環境を予め設定した標準的な道路環境（道路種別・渋滞度・勾配が混在する環境）として、仮想目的地を目的地とみなして経路分割を行ってもよい。
【００６４】
また、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合に、道路環境、例えば目的地の標高とその周辺道路の標高との高低をナビゲーションに保存されている標高の道路環境データにより比較し、目的地がその周辺道路よりも高い場合には、目的地通過後に下り坂が続く可能性が高いとして、目的地と仮想目的地の間を下り坂（例えば目的地より先１ｋｍは勾配−２％で、その先０％）とおき、逆に目的地がその周辺道路よりも低い場合には、目的地通過後に上り坂が続く可能性が高いとして、目的地と仮想目的地の間を上り坂（例えば目的地より先１ｋｍは勾配２％で、その先０％）と設定する。そのうえで、仮想目的地を目的地とみなして経路分割を行ってもよい。
【００６５】
また標高だけでなく、道路種別についても、目的地近傍の道路種別が目的地より先でも継続するようにおいてもよい。
【００６６】
このように、目的地までの距離が所定距離より近い場合に、目的地と仮想目的地間の道路環境を目的地における道路環境に基づき設定するため、例えば、目的地の標高が周辺道路の標高より高い場合には、目的地通過後に下り坂が続く可能性が高いとして、目的地と仮想目的地との間を下り坂と推定し、エンジンとモータの運転点を調整できる。これにより、目的地より先の道路環境を考慮して省燃費運転が可能となる。
【００６７】
また、経路分割数の決定方法には、勾配変化度合い、交差点数、道路種別に応じて決定する方法や、目的地までの距離に比例した分割数を決定する方法などがある。
【００６８】
ステップ５では、各分割区間ｗａｙ（ｉ）における平均勾配、交差点位置、曲率半径、標高などの道路環境を検出する。続くステップ６で、目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）を所定値（例えば６０％）に決定する。
【００６９】
ステップ７で、各分割区間ｗａｙ（ｉ）の道路環境に基づいて現在地と目的地の間の各分割区間ｗａｙ（ｉ）における車速ｐ＿Ｖｓｐ（ｉ）と制駆動力指令値ｐ＿ｔＴｄ（ｉ）を予測する。車速ｐ＿Ｖｓｐ（ｉ）の予測は、例えば次のようにする。誘導経路では道路の制限速度を予測値とする。右左折をする交差点では例えば減速度０．１Ｇで車速が０になり、３秒停止後に加速度０．１Ｇで巡航速度に戻るような車速ｐ＿Ｖｓｐ（ｉ）を予測し、曲線路区間では道路の曲率に応じた加減速度と通過速度に基づいて車速ｐ＿Ｖｓｐ（ｉ）を予測する。また、ＶＩＣＳなどの路車間通信装置から渋滞情報を得た場合は、渋滞区間の渋滞がひどいほど平均車速が低くなるような車速ｐ＿Ｖｓｐ（ｉ）を予測する。各分割区間ｗａｙ（ｉ）の制駆動力指令値ｐ＿ｔＴｄ（ｉ）には、車速ｐ＿ｖｓｐ（ｉ）に応じた走行抵抗分（空気抵抗分＋転がり抵抗分）の駆動力と、前区間との速度差に応じた加減速度分の制駆動力と、道路勾配に応じた車両のポテンシャルエネルギー変化を吸収するための加減速分の制駆動力との和の制駆動力を設定する。
【００７０】
なお、後述するステップ１４で車速と制駆動力指令値の予測のずれが大きいと判断されてステップ７を実行するときは、予測値と実際値とのずれの方向を検出し、ずれの方向を考慮して車速ｐ＿Ｖｓｐ（ｉ）と制駆動力指令値ｐ−ｔＴｄ（ｉ）を再予測する。例えば走行中の予測車速ｐ＿Ｖｓｐ（ｉ）が実際の車速より高い傾向にあるときは予測車速ｐ＿Ｖｓｐ（ｉ）を低めの値にし、走行中の予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）が実際の制駆動力指令値よりも小さいときは予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）を大きめの値にする。あるいは、誘導経路が以前に通ったことのある経路の場合には、以前に通ったときの経路区間の車速ｍ＿Ｖｓｐ（ｉ）を予測車速ｐ＿Ｖｓｐ（ｉ）としてもよいし、予測車速ｐ＿Ｖｓｐ（ｉ）と以前の車速ｍ＿Ｖｓｐ（ｉ）との内分値をとってもよい。ただし、その場合には少なくとも車両が以前に通った経路区間における車速ｍ＿Ｖｓｐ（ｉ）を記憶しておく必要がある。
【００７１】
ステップ８において現在のＳＯＣ（ｄ＿ＳＯＣ）を検出し、続くステップ９では上述した方法によりＳＯＣ換算指標ＳＯＣｃを演算する。さらに標準ＳＯＣ換算指標値（標準制御パラメータ）ＳＯＣｃｍを用いてＳＯＣ換算指標ＳＯＣｃを補正してもよい。標準ＳＯＣ換算指標値ＳＯＣｃｍは、標準的な道路環境において所定のＳＯＣを維持できる値であって、つまり、代表的な道路環境を走行したときに初期ＳＯＣと最終ＳＯＣとが略一致するＳＯＣ換算指標値であり、実験あるいはシミュレーションを用いて予め記憶しておく。今、便宜的に演算したＳＯＣ換算指標ＳＯＣｃをＳＯＣ＿００とおき、ＳＯＣ＿００をＳＯＣｃｍに近づける向きに補正し、補正した値をＳＯＣ換算指標ＳＯＣｃと設定する。
【００７２】
目的地までの道のりが所定距離（例えば、１０ｋｍ）より短い場合のＳＯＣ＿００の補正方法としては、例えば、目的地までの道のりＤｘに応じてＳＯＣ＿００とＳＯＣｃｍの内分点を選択する方法がある。
【００７３】
【数３】

【００７４】
また、目的地までの道のりが所定距離（例えば、１０ｋｍ）を越える場合には、ＳＯＣｃｍ＝ＳＯＣ＿００と設定する。標準ＳＯＣ換算指標値ＳＯＣｃｍを用いた場合には、次のステップ１０の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））は補正後のＳＯＣ換算指標ＳＯＣｃを用いる。
【００７５】
ここでステップ４とステップ９の関係について図９を用いて説明する。ステップ４では、仮想目的地は現在位置より先、例えば１０ｋｍの地点に設定され、そこまでの燃料消費量が抑制されるようにＳＯＣ換算指標ＳＯＣｃが演算され、その値に基づきエンジンとモータの運転点が調整される。演算されたＳＯＣｃは▲３▼のＳＯＣのスケジューリングに相当するものである。対してステップ９では、目的地におけるＳＯＣが目標ＳＯＣとなるように演算されるＳＯＣ換算指標は、▲１▼のＳＯＣのスケジューリングに相当するものであり、標準ＳＯＣ換算指標ＳＯＣｃｍは、▲２▼のＳＯＣのスケジューリングに相当するものである。そしてこれらの値には次の関係がある。▲３▼のＳＯＣのスケジューリングに相当するＳＯＣ換算指標ＳＯＣｃは、目的地におけるＳＯＣが目標ＳＯＣとなるように演算されるＳＯＣ換算指標と、標準ＳＯＣ換算指標ＳＯＣｃｍとの間にある。
【００７６】
すなわち、目的地におけるＳＯＣが目標ＳＯＣとなるように演算されるＳＯＣ換算指標を標準ＳＯＣ換算指標ＳＯＣｃｍに近づける向きに補正することで、ステップ４に行う制御内容と同様であるといえる。
【００７７】
さらに標準ＳＯＣ換算指標値ＳＯＣｃｍを目的地の特徴に基づいて推定した道路環境を走行する際に、ＳＯＣを維持する値として、補正して用いればさらに精度を高めることができる。補正の方法としては、例えば、目的地の標高とその周辺道路の標高との高低をナビゲーションに記憶されている標高データと比較し、その比較結果に基づいて補正する。もし目的地の標高がその周辺道路の標高より高い場合には、目的地通過後に下り坂が続き、回生エネルギが回収できる可能性が高いとしてＳＯＣｃｍを大きめに補正し、たとえば２だけ加算する。対して、目的地の標高がその周辺道路の標高より低い場合には、目的地通過後に上り坂が続き、運動エネルギを必要とする可能性が高いとしてＳＯＣｃｍを小さめに補正し、例えば２だけ減算する。また、目的地とその周辺道路との標高に差異がない場合にはＳＯＣｃｍは補正しない。このような制御を行うことにより、目的地より先の道路環境を考慮することで省燃費運転が可能になる。
【００７８】
ステップ１０で、算出したＳＯＣ換算指標ＳＯＣｃと予測車速ｐ＿Ｖｓｐ（ｉ）と予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とに基づいて、各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））を予測する。まず、ＳＯＣ換算指標ＳＯＣｃと予測車速ｐ＿Ｖｓｐ（ｉ）と予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とに基づいて、上述したように各分割区間ｗａｙ（ｉ）におけるエンジン２およびモーター１、４の仮の運転点を求めると、各分割区間における予測バッテリー充放電電力ｐ＿Ｂａｔ（ｉ）が求まる。したがって、現在のＳＯＣ（ｄ＿ＳＯＣ）を初期値として各分割区間ｗａｙ（ｉ）の予測バッテリー充放電電力ｐ＿Ｂａｔ（ｉ）を時間積分すると、各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））を予測することができる。
【００７９】
ステップ１１で車速センサー２３により車速ｄ＿Ｖｓｐを検出し、続くステップ１２でアクセルセンサー２２によりアクセル開度ｄ＿Ａｃｃを検出する。ステップ１３では、車速とアクセル開度とに基づいて予め設定した制駆動力指令値のテーブルから、検出車速ｄ＿Ｖｓｐと検出アクセル開度ｄ＿Ａｃｃに対応する制駆動力指令値ｄ＿ｔＴｄを表引き演算する。
【００８０】
ステップ１４では、各分割区間ｗａｙ（ｉ）の終点において、各分割区間の例えば平均車速ｄ＿Ｖｓｐ（ｉ）および平均制駆動力指令値ｄ＿ｔＴｄ（ｉ）と、予測車速ｐ＿Ｖｓｐ（ｉ）および予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とのずれがそれぞれの所定値より大きいか否かを判断し、大きい場合にはステップ７へ戻り、所定値以下の場合はステップ１５へ進む。
【００８１】
なお、ずれの指標としては、例えば、車速の二乗誤差と制駆動力指令値の二乗誤差の和ＥＲＲ＿１を指標とする方法がある。
【００８２】
【数４】

【００８３】
上式において、Ｋ１は定数であり、Σは前回予測値を更新した時点から現時点までのｉにおける総和を表す。
【００８４】
また、車両に及ぼす仕事率が、この実施の形態で注目する消費燃料と充放電電力に対する相関が高いとして、仕事率相当値（車速×制駆動力）の二乗誤差ＥＲＲ＿２を指標とする方法もある。
【００８５】
【数５】

【００８６】
上式において、Σは前回予測値を更新した時点から現時点までのｉにおける総和を表す。なお、車速と制駆動力指令値の予測が大きいと判断されてこのステップからステップ７へ進んだ場合には、予測値と実際値とのずれの方向を検出し、ずれの方向を考慮してステップ７で車速ｐ＿Ｖｓｐ（ｉ）と制駆動力指令値ｐ＿ｔＴｄ（ｉ）を再予測する。例えば、走行中の予測車速ｐ＿Ｖｓｐ（ｉ）が実際の車速より高い傾向にあるときは予測車速ｐ＿Ｖｓｐ（ｉ）を低めの値にし、走行中の予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）が実際の制駆動力指令値よりも小さいときは予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）を大きめの値にする。あるいは、誘導経路が以前に通ったことのある経路の場合には、以前に通ったときの経路区間の車速パターンｍ＿Ｖｓｐ（ｉ）を予測車速ｐ＿Ｖｓｐ（ｉ）としてもよいし、予測車速ｐ＿Ｖｓｐ（ｉ）と以前の車速ｍ＿Ｖｓｐ（ｉ）との内分値をとってもよい。ただし、その場合には少なくとも車両が以前に通った経路区間における車速ｍ＿Ｖｓｐ（ｉ）を記憶しておく必要がある。
【００８７】
ステップ１５では、各分割区間ｗａｙ（ｉ）の終点において、現在のＳＯＣ（ｄ＿ＳＯＣ）と予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））とのずれが所定値より大きいか否かを判断し、大きい場合はステップ９へ戻り、所定値以下の場合はステップ１６へ進む。なお、ずれの指標としては例えば次式に示すようなものがある。
【００８８】
【数６】

【００８９】
ステップ１６において、ＳＯＣ換算指標ＳＯＣｃの収束値ＳＯＣｃ＿ｊと、現在の車速検出値ｄ＿Ｖｓｐと、制駆動力指令値の演算値ｄ＿ｔＴｄとに基づいてエンジンとモーターの走行時の正式な運転点を演算する。このとき、検出ＳＯＣ（ｄ＿ＳＯＣ）がメインバッテリー１５の保護のために予め設定されている上下限値付近にある場合には、バッテリー１５の保護を優先させ、ＳＯＣ換算指標ＳＯＣｃの代わりに検出ＳＯＣ（ｄ＿ＳＯＣ）を用いて演算するものとする。続くステップ１７では、エンジン／モーター運転点を実現するように、エンジン２のトルク、モーター１および４のトルク、無段変速機５の変速比、クラッチ３の締結／解放を制御する。
【００９０】
なお、ナビゲーション装置３３が動作していないとき、あるいは目的地が設定されていない場合は、図７および図８に示すフローチャートのステップ８→１１→１２→１３→１６→１７の順に実行する。ただし、目的地が設定されていないがナビゲーション装置３３が動作している場合は、車両が過去に走行したことのある通勤経路や日常良く走行する経路を走行していることを検出し、過去の走行時の情報から例えば通勤先やスーパーなどの目的地を特定してステップ３以降を実行するようにしてもよい。
【００９１】
なお、ＳＯＣ換算指標ＳＯＣｃを演算するに当たっては、すべての分割区間ｗａｙ（ｉ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を演算することになるので、ステップ１０における予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））の演算値としては、ステップ９においてＳＯＣｃ＝ＳＯＣｃ＿ｊとした各分割区間の値を用いてもよい。
【００９２】
また、仮想目的地を設定し、ＳＯＣ換算指標ＳＯＣｃを用いた場合、さらに標準ＳＯＣ換算指標ＳＯＣｃｍを用いた場合には、各分割区間における予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を目標ＳＯＣとし、各区間にてＳＯＣが予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））に一致するように、エンジンおよびモータの運転点を調整し、バッテリの充放電量を加減してもよい。より具体的には、ＳＯＣが予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））より小さい場合には、エンジンの出力を上げ、モータの回生電力を増やすようにエンジン及びモータの運転点を調整することでバッテリへの充電量を増やす。逆に、ＳＯＣが予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））より大きい場合には、エンジンの出力を下げ、モータの回生電力を減らすようにエンジン及びモータの運転点を調整することでバッテリへの放電量を増やせばよい。これにより、ステップ４において、目的地までの道のりが所定距離以下の場合に仮想目的地を設定し、仮想目的地でのＳＯＣを目標ＳＯＣとし、仮想目的地までの総燃料消費量が小さく抑えられるように仮想目的地までの目標ＳＯＣをスケジューリングする（図１０参照）。したがって、目的地以降の車両走行状態を考慮して総燃料消費量が抑制される確率を高めることができる。
【００９３】
また、出発地から目的地までの誘導経路上の道路情報およびＳＯＣに基づき、仮想目的地におけるＳＯＣが目標ＳＯＣとなるようにＳＯＣ換算指標ＳＯＣｃを演算し、ＳＯＣ換算指標ＳＯＣｃに基づいてエンジンおよびモータの運転点を決定するため、総燃料消費量を抑えられる。
【００９４】
このように、第１の実施の形態では、目的地までの誘導経路を分割し、ナビゲーションの道路環境情報に基づいて誘導経路の各分割区間における車速ｐ＿Ｖｓｐと制駆動力指令値ｐ＿ｔＴｄを予測し、各分割区間の予測車速ｐ＿Ｖｓｐと予測制駆動力指令値ｐ＿ｔＴｄおよびバッテリーＳＯＣの初期値ＳＯＣｃ＿０を設定したＳＯＣ換算指標ＳＯＣｃに基づいて燃料利用効率の良いエンジンとモーターの運転点を仮に決定する。次に、各分割区間のエンジンとモーターの仮運転点と現在のＳＯＣ検出値ｄ＿ＳＯＣとに基づいて目的地におけるＳＯＣを予測し、目的地における予測ＳＯＣ（ｐ＿ＳＯＣ）が目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）に略一致するまでＳＯＣ換算指標ＳＯＣｃを収束値ＳＯＣｃ＿ｊに収束させる。そして、車速検出値ｄ＿Ｖｓｐとアクセル開度検出値とに基づいて予め設定した制駆動力指令値テーブルから制駆動力指令値ｄ＿ｔＴｄを表引き演算し、車速検出値ｄ＿Ｖｓｐ、制駆動力指令値の演算値ｄ＿ｔＴｄおよびＳＯＣ換算指標の収束値ＳＯＣｃ＿ｊに基づいて、エンジンとモーターの最終的な運転点を決定する。
【００９５】
この第１の実施形態によれば、ＳＯＣ換算指標ＳＯＣｃを導入し、ナビゲーション装置により検出された道路環境情報に基づいて誘導経路の車速と制駆動力指令値を予測し、目的地よりも先を考慮した上で燃料利用効率の良いエンジンとモーターの運転点を仮に決定する。そのため、目的地までの車速検出値と制駆動力指令値の演算値がそれぞれ予測車速と予測制駆動力指令値と一致するときは、燃料消費量を最少限に抑制することができる。また、実際にエンジンとモーターの運転点を決定し走行するときには、予測車速と予測制駆動力指令値に代えて、車速検出値と制駆動力指令値の演算値を用いて正式な運転点を演算するので、予測車速と予測制駆動力指令値が実際値からずれたときでも、燃料利用効率の悪い運転点が選択されるようなことがなく、燃料消費量の低減効果を維持できる。
【００９６】
《第２の実施の形態》
ＳＯＣ換算指標ＳＯＣｃの他の演算方法を説明する。なお、この第２の実施の形態の構成は図１および図２に示す構成と同様であり、図示と説明を省略する。
【００９７】
図１１および図１２は、ＳＯＣ換算指標の他の演算方法を含む車両制御プログラムを示すフローチャートである。これらのフローチャートにより、第２の実施の形態の動作を説明する。なお、図７および図８に示す動作と同様な動作を行うステップに対しては同一のステップ番号を付して相違点を中心に説明する。
【００９８】
車両コントローラー１６は所定時間ごとにこの制御プログラムを実行する。ステップ１で現在地を検出した後、ステップ８で現在のＳＯＣ（ｄ＿ＳＯＣ）を検出する。続くステップ２で、上述したように目的地の新規入力または変更、誘導経路の逸脱、あるいは渋滞状況の変化があったかどうかを確認し、いずれかがあったときはステップ３へ進み、何もなかったときはステップ１１へ進む。
【００９９】
目的地の新規入力または変更、誘導経路の逸脱、渋滞状況の変化のいずれかがあったときは、ステップ３で目的地までの誘導経路を探索する。次に、ステップ４で、上述したように目的地までの誘導経路をｍ区間ｗａｙ（ｊ）（ｊ＝１〜ｍ）に分割し、さらに各区間ｗａｙ（ｊ）をｐ分割することによって目的地までの誘導経路をｎ（＝ｍ・ｐ）区間ｗａｙ（ｉ）（ｉ＝１〜ｎ）に分割する。
【０１００】
なお、目的地までの距離が遠い場合には、目的地までの誘導経路上の通過点を仮想目的地として経路分割を行ってもよい。一方、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合には、現在地からの距離が所定距離の目的地を通る略延長線上の地点を仮想目的地と設定し、目的地と仮想目的地の道路環境を予め設定した標準的な道路環境（道路種別・渋滞度・勾配が混在する環境）として、仮想目的地を目的地とみなして経路分割を行ってもよい。また、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合には、現在地から所定距離の位置の地点を仮想目的地と設定し、目的地と仮想目的地の道路環境を目的地とその周辺の道路環境に応じて設定する。その上で、仮想目的地を目的地とみなして経路分割を行ってもよい。
【０１０１】
続くステップ５では各分割区間ｗａｙ（ｊ）における平均勾配、交差点位置、曲率半径、標高などの道路環境を検出する。続くステップ６で目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）を所定値（例えば６０％）に決定する。
【０１０２】
ステップ２１において、車両の動力性能を考慮して各区間ｗａｙ（ｊ）ごとの道路環境に応じたＳＯＣの上下限値を設定する。例えば図１３に示すように、経路途中のある区間ｗａｙ（ｋ）から先５ｋｍに渡って上り坂が続くと見込まれる場合は、モーター１、４による駆動力を十分に持続させるために区間ｗａｙ（ｋ）におけるＳＯＣ下限値を５０％とし、１０ｋｍに渡って上り坂が続く場合にはＳＯＣ下限値を６０％にする。
【０１０３】
なお、原則として各分割区間のＳＯＣ上下限値は、図１３に示すようにバッテリー保護のために８０％以下、２０％以上とする。また、ＳＯＣの上下限値は、全区間にわたって設定してもよいし、各区間ｗａｙ（ｊ）ごとに設定してもよい。さらに、誘導経路上の任意の地点に対して設定してもよい。もちろん、上限値のみ、あるいは下限値のみを設定してもよい。
【０１０４】
ステップ７では、上述したように、各分割区間ｗａｙ（ｊ）の道路環境に基づいて現在地と目的地の間の各分割区間ｗａｙ（ｉ）における車速ｐ＿Ｖｓｐ（ｉ）と制駆動力指令値ｐ＿ｔＴｄ（ｉ）を予測する。車速ｐ＿Ｖｓｐ（ｉ）の予測は、例えば次のようにする。誘導経路では区間ｗａｙ（ｊ）の制限速度を予測値とする。また、右左折をする交差点、踏切、あるいは料金所では、例えば減速度０．１Ｇで車速が０になり、３秒停止後に加速度０．１Ｇで巡航速度に戻るような車速ｐ＿Ｖｓｐ（ｉ）を予測し、曲線路区間では道路の曲率に応じた加減速度と通過速度に基づいて車速ｐ＿Ｖｓｐ（ｉ）を予測する。また、ＶＩＣＳなどの路車間通信装置から渋滞情報を得た場合は、渋滞区間の渋滞がひどいほど平均車速が低くなるような車速ｐ＿Ｖｓｐ（ｉ）を予測する。一方、各分割区間ｗａｙ（ｉ）の制駆動力指令値ｐ＿ｔＴｄ（ｉ）には、車速ｐ＿Ｖｓｐ（ｉ）に応じた走行抵抗分（空気抵抗分＋転がり抵抗分）の駆動力と、前区間との速度差に応じた加減速度分の制駆動力と、道路勾配に応じた車両のポテンシャルエネルギー変化を吸収するための加減速分の制駆動力との和の制駆動力を設定する。
【０１０５】
ステップ９では、第１の実施の形態で上述した方法によりＳＯＣ換算指標ＳＯＣｃを演算する。ステップ１０で、算出したＳＯＣ換算指標ＳＯＣｃと予測車速ｐ＿Ｖｓｐ（ｉ）と予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とに基づいて、各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））を予測する。まず、ＳＯＣ換算指標ＳＯＣｃと予測車速ｐ＿Ｖｓｐ（ｉ）と予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とに基づいて、上述したように各分割区間ｗａｙ（ｉ）におけるエンジン２およびモーター１、４の仮の運転点を求めると、各分割区間における予測バッテリー充放電電力ｐ＿Ｂａｔ（ｉ）が求まる。したがって、現在のＳＯＣ（ｄ＿ＳＯＣ）を初期値として各分割区間ｗａｙ（ｉ）の予測バッテリー充放電電力ｐ＿Ｂａｔ（ｉ）を時間積分すると、各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））を予測することができる。
【０１０６】
ステップ２２において、予測した各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））がステップ２１で設定した上下限値を超えているかどうかを確認し、超えていればステップ２３へ進み、超えていなければステップ１１へ進む。
【０１０７】
各分割区間ｗａｙ（ｉ）のＳＯＣ（ｐ＿ＳＯＣ（ｉ））がステップ２１で設定した上下限値を超えていない場合で、かつ目的地までの道のりが所定距離（たとえば、１０ｋｍ）以下の場合に、演算したＳＯＣ換算指標値をＳＯＣ＿００として、このＳＯＣ＿００をコントローラ１６に予め記憶した標準ＳＯＣ換算指標値ＳＯＣｃｍに近づける向きに補正し、補正した値をＳＯＣ換算指標値ＳＯＣｃと設定し、この値に基づいて目的地までの予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を演算した上で、ステップ１１に進むようにしてもよい。この時のＳＯＣ＿００の補正は式（６）に基づくものとする。このとき、標準ＳＯＣ換算指標値ＳＯＣｃｍを目的地の特徴に基づいて推定した道路環境を走行する際に、ＳＯＣを維持する値として、補正して用いればさらに精度を高めることができる。補正の方法としては、ステップ９に記載の通りである。
【０１０８】
予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））が上下限値を超えている場合は、ステップ２３でＳＯＣ換算指標ＳＯＣｃの補正演算を行う。例えば図１４に示すように、予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））が目的地までの経路途中のＰＡ地点で下限値を超える場合（▲１▼）には、下限値を超えないところ（▲２▼の線）までＳＯＣ換算指標ＳＯＣｃを上記数式１により補正して小さくする。逆に、予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））が上限値を超える場合には、上限値を超えないところまでＳＯＣ換算指標ＳＯＣｃを上記数式２により補正して大きくする。ただし、補正の過程で上限値および下限値をともに超えてしまう場合には、車両の現在地に近い方（ｉの値が小さい方）のＳＯＣ予測値ｐ＿ＳＯＣ（ｉ）を優先的に採用し、上下限内に収まるようにＳＯＣ換算指標ＳＯＣｃを数式１または数式２により補正する。
【０１０９】
次に、ステップ２４で各区間ｗａｙ（ｉ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））がＳＯＣ上下限内に収まるようになった地点、例えば図１４に示すように予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））の変化曲線がＳＯＣ上下限値に最接近する地点、または予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））の変化曲線とＳＯＣ上下限値との交点“ＰＡ”を記憶しておく。このとき、▲２▼の線の目的地における予測ＳＯＣ（ｐ＿ＳＯＣ（ｎ））は目標ＳＯＣ（ｔ＿ＳＯＣ）に一致しないため、ステップ２３で演算したＳＯＣ換算指標ＳＯＣｃを目的地まで使用すれば、目的地における実際のＳＯＣが目標ＳＯＣ（ｔ＿ＳＯＣ）に一致しないことになる。そこで、車両が地点ＰＡに達するまではステップ２３で演算したＳＯＣ換算指標ＳＯＣｃを使用し、車両が地点ＰＡに達したことを後述のステップ２６で判定した後は、ステップ９でＳＯＣ換算指標ＳＯＣｃを演算し直し、その値に基づいて車両の運転点を改めて決定していくことで、目的地における実際のＳＯＣを目標ＳＯＣ（ｔ＿ＳＯＣ）にほぼ一致させることができる。
【０１１０】
目的地の新規入力または変更、誘導経路の逸脱、渋滞状況の変化のいずれもなかったときは、ステップ１１で車速センサー２３により車速ｄ＿Ｖｓｐを検出し、続くステップ１２でアクセルセンサー２２によりアクセル開度ｄ＿Ａｃｃを検出する。ステップ１３では、車速とアクセル開度とに基づいて予め設定した制駆動力指令値のテーブルから、検出車速ｄ＿Ｖｓｐと検出アクセル開度ｄ＿Ａｃｃに対応する制駆動力指令値ｄ＿ｔＴｄを表引き演算する。
【０１１１】
ステップ１４では、各分割区間ｗａｙ（ｊ）の終点において、各分割区間の平均車速ｄ＿ｖｓｐ（ｉ）および平均制駆動力指令値ｄ＿ｔＴｄ（ｉ）と、予測車速ｐ＿Ｖｓｐ（ｉ）および予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）とのずれがそれぞれの判定基準値より大きいか否かを判断し、大きい場合にはステップ７へ戻り、予測車速ｐ＿Ｖｓｐ（ｉ）および予測制駆動力指令値ｐ＿ｔＴｄ（ｉ）を再計算する。一方、車速と制駆動力指令値の予測値と実際値のずれが判定基準値以下の場合はステップ１５へ進む。なお、ずれの指標としては、上述した数式３に示す車速の二乗誤差と制駆動力指令値の二乗誤差との和ＥＲＲ＿１を用いたり、あるいは数式４に示す仕事率相当値の二乗誤差ＥＲＲ＿２を用いることができる。ステップ１５では、各分割区間ｗａｙ（ｉ）の終点において、現在のＳＯＣ（ｄ＿ＳＯＣ）と予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））とのずれが判定基準値より大きいか否かを判断し、大きい場合はステップ９へ戻り、ＳＯＣ換算指標ＳＯＣｃを再計算する。一方、ＳＯＣの予測値と実際値とのずれが判定基準値以下の場合はステップ２５へ進む。なお、ずれの指標としては例えば上記数式５に示すＥＲＲ＿３を用いることができる。
【０１１２】
車速、制駆動力指令値およびＳＯＣの予測値と実際値とのずれが小さいときは、ステップ２５で現在のＳＯＣ（ｄ＿ＳＯＣ）とステップ２１で設定したＳＯＣ上下限値との差が所定値δＳＯＣ以下かどうかを確認する。ここで、所定値δＳＯＣには、ＳＯＣがその上下限値に接近したことを判定するための適当な値を設定する。現在のＳＯＣがその上下限値に接近したときはステップ９へ戻り、ＳＯＣ換算指標ＳＯＣｃを再計算する。一方、現在のＳＯＣがその上下限値に接近していないときはステップ２６へ進み、車両が地点ＰＡに到達したかどうかを確認する。ここで、地点ＰＡは、現在のＳＯＣ（ｄ＿ＳＯＣ）がステップ２１で設定したＳＯＣ上下限値に達する地点である。地点ＰＡに到達したときはステップ９へ戻り、ＳＯＣ換算指標ＳＯＣｃを再計算する。一方、まだ地点ＰＡへ到達していないときはステップ１６へ進む。
【０１１３】
ステップ１６では、ＳＯＣ換算指標ＳＯＣｃの収束値ＳＯＣｃ＿ｊと、現在の車速検出値ｄ＿Ｖｓｐと、制駆動力指令値の演算値ｄ＿ｔＴｄとに基づいてエンジンとモーターの走行時の正式な運転点を演算する。続くステップ１７では、エンジン／モーター運転点を実現するように、エンジン２のトルク、モーター１および４のトルク、無段変速機５の変速比、クラッチ３の締結／解放を制御する。
【０１１４】
また、第１の実施形態と同様に各分割区間における予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を目標ＳＯＣとし、各区間にてＳＯＣが予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））に一致するように、エンジンおよびモータの運転点を調整することでバッテリの充放電量を加減すればよい。
【０１１５】
このように、第２の実施の形態では、車両の動力性能を考慮して各区間ｗａｙ（ｉ）ごとの道路環境に応じたＳＯＣの上下限値を設定し、ＳＯＣ換算指標ＳＯＣｃと各区間ｗａｙ（ｉ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を演算する。そして、各区間ｗａｙ（ｉ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））がＳＯＣの上下限値を超えている場合は、上下限値の範囲内に収まるようにＳＯＣ換算指標ＳＯＣｃを再計算し、各区間ｗａｙ（ｉ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））の変化曲線がＳＯＣ上下限値に最接近する地点、または予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））の変化曲線とＳＯＣ上下限値との交点ＰＡを記憶する。ＳＯＣ換算指標ＳＯＣｃに基づいてエンジン／モーターの運転点を決定し走行しているときに、現在のＳＯＣ（ｄ＿ＳＯＣ）がＳＯＣ上下限値に接近または上記地点ＰＡに到達したら、それ以降のＳＯＣ換算指標ＳＯＣｃを演算し直し、新しいＳＯＣ換算指標ＳＯＣｃに基づいてエンジン／モーターの運転点を決定し、目的地への走行を続ける。これにより、目的地までとどまらず、目的地より先も考慮した上で、車両を効率よく運転させることがきる。
【０１１６】
《第３の実施の形態》
ＳＯＣ換算指標ＳＯＣｃの他の演算方法を説明する。なお、この第３の実施の形態の構成は図１および図２に示す構成と基本的に同様であるが、この第３の実施の形態では目的地までの各分割区間の車速と制駆動力指令値を予測する走行条件予測機能１６ａ（図２参照）が不要である。
【０１１７】
図１５および図１６は、ＳＯＣ換算指標の他の演算方法を含む車両制御プログラムを示すフローチャートである。これらのフローチャートにより、第３の実施の形態の動作を説明する。なお、図７および図８に示す動作と同様な動作を行うステップに対しては同一のステップ番号を付して相違点を中心に説明する。
【０１１８】
車両コントローラー１６は所定時間ごとにこの制御プログラムを実行する。ステップ１において現在地を検出する。続くステップ２で、目的地の新規入力または変更、誘導経路の逸脱、あるいは渋滞状況の変化があったかどうかを確認し、いずれかがあったときはステップ３へ進み、何もなかったときはステップ１１へ進む。目的地の新規入力または変更、誘導経路の逸脱、渋滞状況の変化のいずれかがあったときは、ステップ３で目的地までの誘導経路を探索する。続くステップ４では、上述したように道路環境の内の特徴のある地点を区分点として目的地までの誘導経路をｍ区間ｗａｙ（ｊ）（ｊ＝１〜ｍ）に分割する。
【０１１９】
なお、目的地までの距離が遠い場合には、目的地までの誘導経路上の通過点を仮の目的地として経路分割を行ってもよい。一方、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合には、現在地からの距離が所定距離の目的地を通る略延長線上の地点を仮想目的地と設定し、目的地と仮想目的地の道路環境を予め設定した標準的な道路環境（道路種別・渋滞度・勾配が混在する環境）として、仮想目的地を目的地とみなして経路分割を行ってもよい。また、目的地までの距離が所定距離（例えば、１０ｋｍ）より近い場合には、現在地から所定距離の位置の地点を仮想目的地と設定し、目的地と仮想目的地の道路環境を目的地とその周辺の道路環境に応じて設定する。その上で、仮想目的地を目的地とみなして経路分割を行ってもよい。
【０１２０】
ステップ５で各分割区間ｗａｙ（ｊ）における平均勾配、交差点位置、曲率半径、標高などの道路環境を検出し、続くステップ６で、目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）を所定値（例えば６０％）に決定する。
【０１２１】
次に、ステップ８で現在のＳＯＣ（ｄ＿ＳＯＣ）を検出し、続くステップ３１で次のようにしてＳＯＣ換算指標ＳＯＣｃを演算する。まず、道路環境ごとに走行パターンを想定し、それらの走行パターンをＳＯＣ換算指標ＳＯＣｃで走行した場合の単位距離あたりのＳＯＣ変化量データ（MAP2Ｄ＿ＳＯＣ）として予めメモリに記憶しておく。そして、このデータ（ＭＡＰ２Ｄ＿ＳＯＣ）からＳＯＣ換算指標ＳＯＣｃと各区間ｗａｙ（ｊ）ごとの道路環境とに対応したＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｊ）を表引き演算し、現在のＳＯＣ（ｄ＿ＳＯＣ）を初期値として各区間ｗａｙ（ｊ）のＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｊ）を積分することによって、各区間ｗａｙ（ｊ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｊ））と目的地における予測ＳＯＣ（ｐ＿ＳＯＣ（ｍ））を求める。この演算を、目的地における予測ＳＯＣ（ｐ＿ＳＯＣ（ｍ））が目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）とほぼ一致するまで実行し、両者がほぼ一致したときのＳＯＣ換算指標を最終的な指標ＳＯＣｃとする。
【０１２２】
または標準ＳＯＣ換算指標値ＳＯＣｃｍを用いてＳＯＣ換算指標ＳＯＣｃを補正してもよい。標準ＳＯＣ換算指標値ＳＯＣｃｍは、標準的な道路環境においてＳＯＣを維持できる値であって、つまり、代表的な道路環境を走行したときに初期ＳＯＣと最終ＳＯＣとが略一致するＳＯＣ換算指標値であり、実験あるいはシミュレーションを用いてコントローラに予め記憶しておく。今、便宜的に演算したＳＯＣ換算指標ＳＯＣｃをＳＯＣ＿００とおき、ＳＯＣ＿００をＳＯＣｃｍに近づける向きに補正し、補正した値をＳＯＣ換算指標ＳＯＣｃと設定する。
【０１２３】
目的地までの道のりが所定距離（例えば、１０ｋｍ）より短い場合のＳＯＣ＿００の補正方法としては、例えば、目的地までの道のりＤｘに応じてＳＯＣ＿００とＳＯＣｃｍの内分点を選択する方法がある。
【０１２４】
【数６】

【０１２５】
また、目的地までの道のりが所定距離（例えば、１０ｋｍ）を越える場合には、ＳＯＣｃｍ＝ＳＯＣ＿００と設定する。標準ＳＯＣ換算指標値ＳＯＣｃｍを用いた場合には、次のステップ１０の予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））は補正後のＳＯＣ換算指標ＳＯＣｃを用いる。
【０１２６】
さらに標準ＳＯＣ換算指標値ＳＯＣｃｍを目的地の特徴に基づいて推定した道路環境を走行する際に、ＳＯＣを維持する値として、ステップ９に示すように補正して用いればさらに精度を高めることができる。
【０１２７】
ステップ１１で車速センサー２３により車速ｄ＿Ｖｓｐを検出し、続くステップ１２でアクセルセンサー２２によりアクセル開度ｄ＿Ａｃｃを検出する。ステップ１３では、車速とアクセル開度とに基づいて予め設定した制駆動力指令値テーブルから、検出車速ｄ＿Ｖｓｐと検出アクセル開度ｄ＿Ａｃｃに対応する制駆動力指令値ｄ＿ｔＴｄを表引き演算する。
【０１２８】
ステップ３２において、各区間ｗａｙ（ｊ）のＳＯＣ変化量（ｐ＿ｄ＿ＳＯＣ（ｊ））の誤差が大きいかどうかを判定する。つまり、各区間ｗａｙ（ｊ）の終点ごとに、直前に通過した区間ｗａｙ（ｋ）の実際のＳＯＣ変化量（ｄ＿ｄ＿ＳＯＣ（ｋ））と算出したＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｋ）とを比較し、ずれが大きい場合は補正する。なお、ずれの判定基準値には例えば次式により求めた値ＥＲＲ４を用いることができる。
【０１２９】
【数７】

【０１３０】
ずれが大きいときはステップ８へ戻ってＳＯＣ換算指標ＳＯＣｃを再計算し、ずれが小さいときはステップ１５へ進む。
【０１３１】
ステップ１５では、各分割区間ｗａｙ（ｊ）の終点において、現在のＳＯＣ（ｄ＿ＳＯＣ）と予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））とのずれが判定基準値より大きいか否かを判断し、大きい場合はステップ９へ戻り、判定基準値以下の場合はステップ１６へ進む。なお、判定基準値としては上記数式３に基準値ＥＲＲ＿３を用いることができる。示すずれの指標としては例えば次式に示すようなものがある。
【０１３２】
ステップ１６において、ＳＯＣ換算指標ＳＯＣｃの収束値ＳＯＣｃ＿ｊと、現在の車速検出値ｄ＿Ｖｓｐと、制駆動力指令値の演算値ｄ＿ｔＴｄとに基づいてエンジンとモーターの走行時の正式な運転点を演算する。このとき、検出ＳＯＣ（ｄ＿ＳＯＣ）がメインバッテリー１５の保護のために予め設定されている上下限値付近にある場合には、バッテリー１５の保護を優先させ、ＳＯＣ換算指標ＳＯＣｃの代わりに検出ＳＯＣ（ｄ＿ＳＯＣ）を用いて演算するものとする。続くステップ１７では、エンジン／モーター運転点を実現するように、エンジン２のトルク、モーター１および４のトルク、無段変速機５の変速比、クラッチ３の締結／解放を制御する。
【０１３３】
また、第１の実施形態と同様に各分割区間における予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））を目標ＳＯＣとし、各区間にてＳＯＣが予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））に一致するように、エンジンおよびモータの運転点を調整することでバッテリの充放電量を加減すればよい。
【０１３４】
なお、走行経路の道路環境情報、ＳＯＣ換算指標およびＳＯＣ変化量を記憶しておき、この過去の走行経路のデータを考慮して区間ｗａｙ（ｊ）ごとのＳＯＣ変化量を予測するようにしてもよい。それにより、より正確な区間ｗａｙ（ｊ）ごとのＳＯＣ変化量を予測することができる。
【０１３５】
このように、第３の実施の形態によれば、道路環境ごとに走行パターンを想定し、それらの走行パターンを種々のＳＯＣ換算指標で走行した場合の単位走行距離あたりのＳＯＣ変化量データを予めメモリに記憶しておく。そして、この単位走行距離あたりのＳＯＣ変化量データから、ＳＯＣ換算指標ＳＯＣｃと各区間ｗａｙ（ｊ）ごとの道路環境とに対応したＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｊ）を表引き演算し、現在のＳＯＣ（ｄ＿ＳＯＣ）を初期値として各区間ｗａｙ（ｊ）のＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｊ）を積分することによって、各区間ｗａｙ（ｊ）の予測ＳＯＣ（ｐ＿ＳＯＣ（ｊ））と目的地における予測ＳＯＣ（ｐ＿ＳＯＣ（ｍ））を求める。この演算を目的地における予測ＳＯＣ（ｐ＿ＳＯＣｍ）が目的地における目標ＳＯＣ（ｔ＿ＳＯＣ）とほぼ一致するまで実行し、両者がほぼ一致したときのＳＯＣ換算指標を最終的な指標ＳＯＣｃとする。このＳＯＣ換算指標ＳＯＣｃに基づいてエンジン／モーターの運転点を決定し走行しているときに、各区間ｗａｙ（ｋ）の実際のＳＯＣ変化量ｄ＿ｄ＿ＳＯＣ（ｋ）と算出したＳＯＣ変化量ｐ＿ｄ＿ＳＯＣ（ｋ）とを比較し、ずれが大きい場合はＳＯＣ換算指標（ＳＯＣ）を補正する。また、各区間ｗａｙ（ｊ）において、現在のＳＯＣ（ｄ＿ＳＯＣ）と予測ＳＯＣ（ｐ＿ＳＯＣ（ｉ））とを比較し、ずれが判定基準値よりも大きい場合はＳＯＣ換算指標（ＳＯＣ）を補正する。これにより、目的地までの燃料利用効率を向上させながらこれにより、目的地までとどまらず、目的地より先も考慮した上で、車両を効率よく運転させることがきる。
【０１３６】
以上の実施の形態では、燃料増加量Δｆｕｅｌに対する充電電力増加量Δｂａｔの比（Δｂａｔ／Δｆｕｅｌ）、すなわち感度ＳをＳＯＣ換算指標とする例を示したが、ＳＯＣ換算指標は感度Ｓに限定されない。例えば、ＳＯＣが低いときには発電を促進し、高いときには発電を抑制する制御を行うハイブリッド車両に対しては、ＳＯＣそのものをＳＯＣ換算指標としてもよい。この場合は、車両の進行経路上に所定距離以上の下り坂がある場合には、目標ＳＯＣを検出ＳＯＣに対して小さめに補正すればよい。また、ＳＯＣ検出値と目的地における目標ＳＯＣとの差が大きいほどＳＯＣの補正量を大きくしてもよい。
【０１３７】
また本実施形態においては、バッテリの充電状態を示すＳＯＣを用いて説明してきたが、これに限らずバッテリの蓄電状態を示すものであればよく、例えばＤＯＤでもよい。
【０１３８】
なお、運転者に代わり状況に応じて車両の制駆動力を自動調整するような制駆動力自動調整システムにおいては、上述した実施の形態の“アクセル開度”を制駆動力自動調整システムの制駆動力指令値に置き換えることによって、上述した実施の形態と同様な効果を得ることができる。
【０１３９】
また、上述した一実施の形態では、クラッチ３の締結によりパラレル・ハイブリッド走行を実現するとともに、クラッチ３の開放によりシリーズ・ハイブリッド走行も行う車両への適用例を示したが、パラレル・ハイブリッド走行のみ、またはシリーズ・ハイブリッド走行のみを行う車両へも同様に適用できる。
【０１４０】
さらに、上述した一実施の形態では無段変速機を例に上げて説明したが、変速機は無段変速機に限定されず、有段変速機でもよい。また、変速機の配置も上述した一実施の形態に限定されない。
【０１４１】
さらにまた、本願発明は、前輪駆動、後輪駆動、４輪駆動などのすべての駆動方式の車両に適用することができ、エンジンで前輪を駆動し、モーターで後輪を駆動する形態などのすべての駆動源形態の車両に適用することができる。
【０１４２】
もちろん、遊星歯車を備えエンジンとモータの動作回転数を自在に取れるような機構のハイブリッドシステムにも同じように適用できる。
【０１４３】
このようなハイブリッドシステムとしては、たとえば、遊星歯車のプラネタリキャリアにエンジンを接続し、サンギアに発電モータ、リングギアに車両駆動用モータを接続して構成されるもの（Toyota Hybrid System）などがある。前述の実施例の形態では、エンジン及びモータの作動回転速度は、無段変速機の変速比を調整することにより調整できるシステムへの適用を示したが、このようなハイブリッドシステムにおいては、遊星歯車の特性を鑑み、発電モータの回転速度を調整することにより、エンジン及びモータの作動回転速度を調整できるシステムとして、実施例と同様の考え方により本発明を適用することができる。
【０１４４】
もちろん同様に、他の遊星歯車を備えたハイブリッドシステムにも適用可能である。例えば図１７、１８は、遊星歯車機構を２セット有する形態であるが、本機構においてもモータ１（図示ＭＧ１）あるいはモータ２（図示ＭＧ２）の回転速度を調整することにより、エンジンおよびモータの差動回転数を調整することが可能であり、実施例と同様の考え方により本発明を適用することができる。
【０１４５】
本発明は、上記した実施形態に限定されるものではなく、本発明の技術的思想の範囲内でさまざまな変更がなしうることは明白である。
【図面の簡単な説明】
【図１】一実施の形態の構成を示す図である。
【図２】同じく一実施の形態の構成を示す図である。
【図３】ＳＯＣ換算指標の演算方法を説明するための図である。
【図４】エンジンの運転点を示す図である。
【図５】エンジンの燃料増加量Δｆｕｅｌに対する充電電力増加量δｂａｔ、充電電力Ｂａｔ、感度Ｓを示す図である。
【図６】クラッチの動作点を設定するマップである。
【図７】第１の実施形態の車両制御プログラムを示すフローチャートである。
【図８】同じく車両制御プログラムを示すフローチャートである。
【図９】請求項４の作用を説明する図である。
【図１０】請求項１の作用を説明する図である。
【図１１】第２の実施の形態の車両制御プログラムを示すフローチャートである。
【図１２】同じく車両制御プログラムを示すフローチャートである。
【図１３】ＳＯＣ上下限値の設定方法を説明するための図である。
【図１４】ＳＯＣ換算指標の補正方法を説明するための図である。
【図１５】第３の実施の形態の車両制御プログラムを示すフローチャートである。
【図１６】同じく車両制御プログラムを示すフローチャートである。
【図１７】本発明を適用できる他のハイブリッドシステムを説明する図である。
【図１８】本発明を適用できる他のハイブリッドシステムを説明する図である。
【図１９】従来の方法の課題を説明する図である。
【符号の説明】
１ モータ
２ エンジン
４ モータ
５ 無段変速機
９ 油圧装置
１０ モータ
１１ インバータ
１２ インバータ
１３ インバータ
１５ バッテリ
１６ コントローラ
２３ 車速センサ
２５ ＳＯＣセンサ
３３ ナビゲーション装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a hybrid vehicle, and more particularly, to a control device for a hybrid vehicle that improves fuel consumption while maintaining a storage amount of a battery in a desired range.
[0002]
[Prior art]
There is a hybrid vehicle control device that obtains road information related to a guidance route from a navigation device in advance and controls an engine and a motor so that the guidance route can be driven with low fuel consumption based on the road information (see, for example, Patent Document 1). .
[0003]
In this prior art, an SOC (State Of Charge, indicating the state of charge of the battery) conversion index SOCc is introduced as a parameter representing the charge / discharge degree of the battery, and the fuel consumption and driving force characteristics in the guide route traveling are improved. I am doing so.
[0004]
The SOC conversion index SOCc is associated in advance with the operating points of the engine and the motor such that the larger the value, the more the battery discharge amount (less charge amount) and the higher the fuel consumption efficiency of the engine. Accordingly, if the SOC conversion index SOCc is set to a large value, an operating point with high fuel consumption efficiency can be realized although the amount of charge to the battery is small (the discharge amount is large), and conversely, the SOC conversion index SOCc is set to a small value. For example, it is possible to realize an operating point with low fuel consumption efficiency but with a large amount of charge to the battery (low amount of discharge). In particular, before driving the route, based on the road information of the guidance route obtained from the navigation device, the SOC conversion index SOCc capable of realizing low fuel consumption while maintaining the SOC within a predetermined range is calculated, and the actual accelerator during driving is calculated. By determining the operating points of the engine and the motor based on the opening degree, the actual vehicle speed, and its SOC-converted index SOCc, the fuel consumption at the time of traveling through the guide route is reduced. Further, the fuel consumption reduction effect is further improved by repeating the recalculation of the SOC conversion index SOCc during traveling on the guidance route, and the braking / driving force characteristics of the vehicle are determined by determining the SOC conversion index SOCc so that the SOC falls within a predetermined range. Has improved.
[0005]
Here, the SOC conversion index SOCc is derived so that the SOC at the destination becomes a preset target value (hereinafter referred to as t_SOC).
[0006]
[Patent Document 1]
JP 2001-298805 A
[0007]
[Problems to be solved by the invention]
However, such a conventional method has the following problems.
[0008]
Problem 1) Assuming that the distance from the departure point to the destination is relatively short (for example, 100 m) and the difference between the current SOC and the t_SOC at the destination is large (for example, the difference is 30%), FIG. There is a case of b). In the case of (a), an operating point in which the fuel consumption efficiency of the engine is remarkably bad is realized although the amount of charge is large so that the SOC at the destination becomes t_SOC. As a result, although the SOC at the destination approaches t_SOC, the total fuel consumption including after passing through the destination is not always good, and there is room for improving the fuel consumption. In the case of (b), the battery power is positively discharged so that the SOC at the destination becomes t_SOC. As a result, although the SOC at the destination approaches t_SOC, the total fuel consumption including after passing through the destination is not always good, and there is room for improving the fuel consumption.
[0009]
Problem 2) Even if the road from the departure point to the destination is long, depending on the driving situation of the vehicle (for example, by taking a rest at a highway SA, PA or a store along a general road) There is a case where the difference between the current SOC and t_SOC at the destination becomes large (for example, the difference is 30%) at a point approaching the destination (for example, 100 m before). In such a case, the recalculation of the SOC conversion index SOCc has the same problem as the problem 1.
[0010]
In other words, the conventional method only considers the destination, and does not consider driving beyond the destination, so there is a problem that the total fuel consumption including the destination is not necessarily improved. It was.
[0011]
The present invention has been made in view of such problems, and an object thereof is to provide a control device for a hybrid vehicle that improves fuel consumption.
[0012]
[Means for Solving the Problems]
The present invention relates to a hybrid vehicle control device that includes an engine and a motor as braking / driving sources, and a battery that transmits and receives electric power between the motor, vehicle speed detection means for detecting the speed of the vehicle, The braking / driving force command value detecting means for detecting the braking / driving force command value, the storage state detecting means for detecting the storage state of the battery, and a map including road information are stored, and the current position of the vehicle is specified on the map. A navigation device for estimating a vehicle travel route to a destination, a virtual destination setting means for setting a position far from the destination as a virtual destination when the distance to the destination is closer than a predetermined value, and a current position A first target power storage state setting means for setting a target power storage state at a virtual destination when traveling from a virtual destination to a virtual destination, and when the distance to the destination is less than a predetermined value, Second target power storage state control means for setting a target power storage state to the virtual destination so that fuel consumption to the ground is reduced, and the setting based on the vehicle speed detection value, the braking / driving force command value, and the power storage state An operating point determining means for determining the operating point of the engine and the motor so as to achieve the set target storage state, an engine operating point adjusting means for adjusting the operating point of the engine based on the determined operating point, and the determined operating point Motor operating point adjusting means for adjusting the operating point of the motor on the basis thereof.
[0013]
【The invention's effect】
According to the present invention, when the distance to the destination is closer than the predetermined distance, the virtual destination is set, and the target storage state to the virtual destination is set so that the fuel consumption to the virtual destination is suppressed. In order to control, the fuel consumption can be suppressed in consideration of the running state of the vehicle after the actual destination.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the configuration of an embodiment. In the figure, a thick solid line indicates a transmission path of mechanical force, and a thick broken line indicates a power line. A thin solid line indicates a control line, and a double line indicates a hydraulic system.
[0015]
The power train of this hybrid vehicle includes a motor 1, an engine 2, a clutch 3, a motor 4, a continuously variable transmission 5, a speed reducer 6, a differential device 7, and drive wheels 8. A clutch 3 is interposed between the engine 2 and the motor 4. The output shaft of the motor 1 and the input shaft of the engine 2 are connected to each other, and the output shaft of the engine 2 and the input shaft of the clutch 3 are connected to each other. The output shaft and the input shaft of the motor 4 are connected to each other, and the output shaft of the motor 4 and the input shaft of the continuously variable transmission 5 are connected to each other.
[0016]
When the clutch 3 is engaged, the engine 2 and the motor 4 serve as a vehicle propulsion source, and when the clutch 3 is released, only the motor 4 serves as a vehicle propulsion source. The driving force of at least one of the engine 2 and the motor 4 is transmitted to the driving wheel 8 via the continuously variable transmission 5, the speed reduction device 6, and the differential device 7. The continuously variable transmission 5 is pumped with hydraulic fluid from the hydraulic device 9 to be clamped and lubricated. The oil pump (not shown) of the hydraulic device 9 is driven by the motor 10.
[0017]
The motors 1, 4, and 10 are AC machines such as a three-phase synchronous motor or a three-phase induction motor. The motor 1 is mainly used for engine start and power generation, and the motor 4 is mainly used for vehicle propulsion and braking. The motor 10 is for driving an oil pump of the hydraulic device 9. The motors 1, 4, and 10 are not limited to AC machines, and DC motors can also be used. In addition, when the clutch 3 is engaged, the motor 1 can be used for vehicle propulsion and braking, and the motor 4 can be used for engine starting and power generation.
[0018]
The clutch 3 is a powder clutch and can control the transmission torque. The clutch 3 may be a dry single plate clutch or a wet multi-plate clutch. The continuously variable transmission 5 is a continuously variable transmission such as a belt type or a toroidal type, and can control the gear ratio steplessly.
[0019]
The driving of the motors 1, 4, and 10 is controlled by inverters 11, 12, and 13, respectively. In addition, when using a direct current motor for the motors 1, 4, and 10, a DC / DC converter is used instead of an inverter. The inverters 11 to 13 are connected to the main battery 15 via a common DC link 14. The inverter 11 to 13 converts the DC charging power of the main battery 15 into AC power and supplies it to the motors 1, 4, 10. The main battery 15 is charged by converting the AC generated power 4 into DC power. Since the inverters 11 to 13 are connected to each other via the DC link 14, the power generated by the motor during the regenerative operation can be directly supplied to the motor during the power running operation without going through the main battery 15. it can. As the main battery 15, various batteries such as a lithium ion battery, a nickel / hydrogen battery, a lead battery, and an electric double layer capacitor, so-called power capacitor, can be used.
[0020]
The vehicle controller 16 includes peripheral parts such as a microcomputer and a memory. The rotational speed and output torque of the motors 1, 4 and 10, the rotational speed and output torque of the engine 2, the engagement and release of the clutch 3, and the continuously variable transmission 5 The gear ratio is controlled.
[0021]
As shown in FIG. 2, the vehicle controller 16 includes a key switch 20, a brake switch 21, an accelerator sensor 22, a vehicle speed sensor 23, a battery temperature sensor 24, a battery SOC detector 25, an engine rotation sensor 26, a throttle sensor 27, and the like. Connected.
[0022]
The key switch 20 is turned on (closed) when the vehicle key is set to the ON position or the START position. The brake switch 21 detects the depression state of a brake pedal (not shown), and the accelerator sensor 22 detects the depression amount of the accelerator pedal (hereinafter referred to as accelerator opening). The vehicle speed sensor 23 detects the traveling speed of the vehicle, and the battery temperature sensor 24 detects the temperature of the main battery 15. The battery SOC detection device 25 detects the SOC of the main battery 15, and the engine rotation sensor 26 detects the rotation speed of the engine 2. Further, the throttle sensor 27 detects the throttle valve opening of the engine 2.
[0023]
Further, a fuel injection device 30, an ignition device 31, a throttle valve control device 32, a navigation device 33, and the like of the engine 2 are connected to the vehicle controller 16. The controller 16 controls the fuel injection device 30 to adjust supply and stop of fuel to the engine 2 and the amount of fuel injection, and also controls the ignition device 31 to ignite the engine 2 and control the throttle valve adjustment device 33. Then, the torque of the engine 2 is adjusted.
[0024]
The navigation device 33 is a satellite navigation device that detects the current location and travel route with a GPS receiver, a self-contained navigation device that detects the current location and travel route with a gyrocompass, and a road-to-vehicle communication device that receives traffic information and road information such as VICS. It has a road map database, etc., searches for the optimum route to the destination, and guides passengers along the optimum route.
[0025]
The navigation device 33 also includes a route division function 33a, a road environment detection function 33b, and a target SOC determination function 33c realized by microcomputer software. The route division function 33a divides the guidance route to the destination. The road environment detection function 33b detects road curvature radii of divided sections, road gradients, presence / absence of intersections / tunnels / crossings, regulation information such as speed limits, and area information such as city roads and mountain roads. The target SOC determination function 33c determines the target battery charge state t_SOC of the main battery 15 at the destination.
[0026]
The vehicle controller 16 includes a travel condition prediction function 16a, an SOC conversion index calculation function 16b, and an engine / motor operating point calculation function 16c realized by software of a microcomputer.
[0027]
The traveling condition prediction function 16a predicts the vehicle speed and braking / driving force command value of each divided section based on the road environment of each divided section. The SOC conversion index calculation function 16b calculates an SOC conversion index (control parameter) SOCc used when determining the engine / motor operating point. The engine / motor operating point calculation function 16c calculates the operating points of the engine 2 and the motors 1 and 4 based on the SOCc, the vehicle speed, and the braking / driving force command value.
[0028]
<< Calculation method of SOC conversion index SOCc >>
In this embodiment, the engine 2 and the motors 1 and 4 are controlled so that the SOC of the main battery 15 becomes the target value t_SOC while suppressing the fuel consumption in the guide path to the minimum.
[0029]
First, the target SOC (t_SOC) at the destination is set. This t_SOC is the target value of SOC at the destination, but the SOC of the main battery 15 does not necessarily have to be this t_SOC in the middle of the route to the destination, and the engine 2 and the motor are based on this t_SOC during traveling. The operating points of 1 and 4 are not determined. The t_SOC setting method at this destination includes a method of simply setting a constant value, for example 70%, regardless of the road environment, a method of determining according to the altitude of the destination, for example, the higher the altitude, There is a method of setting a small t_SOC in the hope that the traveling energy can be collected in the main battery 15.
[0030]
Next, in this embodiment, in order to set the SOC of the main battery 15 at the destination to t_SOC while minimizing the fuel consumption in the middle of the route to the destination, the engine on the way to the destination is set to t_SOC. 2 and an SOC conversion index SOCc for determining the operating points of the motors 1 and 4 are obtained by calculation.
[0031]
When the SOCc is large, charging is performed only when the power increase amount Δbat per unit fuel increase amount Δfuel for battery charging increases, that is, when the fuel use efficiency at the time of battery charging increases. On the contrary, when the SOCc is small, the engine / motor operating point is determined so that charging is performed even when the fuel use efficiency during battery charging is low.
[0032]
A method of calculating the SOC conversion index (control parameter) SOCc will be described with reference to FIG.
[0033]
A case where the traveling pattern to the destination is a pattern as shown in FIG. 3A will be described as an example. In FIG. 3A, the route from the departure point to the destination is divided into n sections way (i) (i = 1, 2,..., N), and the road environment for each section way (i). Based on the vehicle speed p_Vsp (i) and the braking / driving force command value p-tTd (i). A method for predicting the vehicle speed p_Vsp (i) and the braking / driving force command value p-tTd (i) will be described later. 3 (b) to 3 (d), respectively, set three types of fixed values SOCc_h, SOCc_m, and SOCc_l (where SOCc_h>SOCc_m> SOCc_l) as the SOCc, and the operation of the engine 2 and the motors 1 and 4 is performed. The minimum fuel consumption, charge / discharge amount, and SOC change when a point is determined are shown.
[0034]
As described above, the SOCc is an index representing the fuel utilization efficiency during battery charging. Therefore, as apparent from FIGS. 3B to 3D, the final SOC at the destination has the smallest value f_SOCc_h when SOCc_h is set to the maximum value SOCc_h, and the smallest SOCc. When the value SOCc_l is set, the value f_SOcc_l is the largest. That is, the actual SOC at the destination becomes smaller as the engine / motor operating point is set so as to charge only when the fuel utilization efficiency is high.
[0035]
Some value is set in the SOCc, and an engine / motor operating point determination method to be described later is performed based on the predicted vehicle speed p_Vsp (i) and the predicted braking / driving force command value p-tTd (i) of each divided section way (i). A temporary operating point of the engine 2 and the motors 1 and 4 is determined. Then, a time integration value p_Bat (i) of the charge / discharge power Bat of each divided section way (i) is obtained, and the predicted battery charge / discharge power p_Bat () of each divided section way (i) is determined using the current SOC (d_SOC) as an initial value. If i) is integrated over time, the predicted SOC (p_SOC (i)) in each divided section way (i) and the predicted SOC (p_SOC (n)) at the destination can be obtained.
[0036]
As described above, if the SOCc is increased, the predicted SOC (p_SOC (n)) at the destination is decreased. Therefore, the initial value SOCc_0 is set in the SOCc (SOCc = SOCc_0), and the predicted SOC at the destination (p_SOC (n )), If the predicted SOC at the destination (p_SOC (n)) is greater than t_SOC at the destination, SOCc is
[0037]
[Expression 1]

[0038]
Reduce and recalculate. Conversely, if the predicted SOC at the destination (p_SOC (n)) is less than t_SOC at the destination, SOCc is
[0039]
[Expression 2]

[0040]
Increase to recalculate.
[0041]
The above calculation is repeated until the predicted SOC (p_SOC (n)) at the destination substantially coincides with the t_SOC at the destination, that is, until the difference between the two becomes equal to or less than a predetermined value, and SOCc_j (j Is an integer equal to or greater than 0) as the final SOC conversion index SOCc. This calculation is performed when there is a new input or change of the destination, a departure from the guidance route, or a change in the traffic jam situation.
[0042]
Here, α is a fixed value that does not diverge the repetitive calculation. Alternatively, SOCc_0 may be determined according to traffic information or the like. For example, if the current SOC (d_SOC) is small when there is heavy traffic congestion, SOCc_0 is set to a smaller value. Alternatively, in the case of a route that has traveled before, the initial value is a value that is corrected to be smaller as the current SOC (d_SOC) is smaller based on the SOCc at that time.
[0043]
<Engine / motor operating point determination method>
Next, a method for determining the engine / motor operating point when the clutch is engaged will be described with reference to FIGS. The operation points A, N, B, C, D, and E in FIG. 4 correspond to the operation points A, N, B, C, D, and E in FIG.
[0044]
When calculation is performed to determine the SOC conversion index SOCc, the temporarily set SOCc, the predicted vehicle speed p_Vsp (i) and the predicted braking / driving force command value p_tTd (i) for each divided section way (i) Based on the above, temporary operating points of the engine 2 and the motors 1 and 4 are determined. On the other hand, when the determination of SOCc is completed and the vehicle is actually traveling toward the destination, it is based on the determined SOCc (= SOCc_j), the vehicle speed detection value d_Vsp, and the braking / driving force command value calculation value d_tTd. Thus, the official operating point when the engine 2 and the motors 1 and 4 are running is determined. The calculation value d_tTd of the braking / driving force command value is obtained by a table calculation from a braking / driving force command value table set in advance based on the vehicle speed detection value d_Vsp and the accelerator opening detection value.
[0045]
In any of the operating point determinations, the operating point is determined so that charging is performed only when the SOCc_j or SOCc is larger and the fuel use efficiency during battery charging is higher.
[0046]
FIG. 4 shows the engine / motor operating point when the vehicle speed is 50 km / h and the braking / driving force command value is 1000 N, and FIG. 5 shows the relationship between the engine / motor operating point and the battery charge amount at the same vehicle speed and braking / driving force command value. Indicates.
[0047]
In FIG. 4, the thick line is the optimum fuel consumption line that connects the operating points at which the fuel consumption is minimized when the same engine output is obtained. The efficiency of the engine 2, the motors 1, 4, and the continuously variable transmission 5 is taken into consideration. It has become a thing. The engine / motor operating point is always set on this bold line. Point A is when the vehicle is driven by the motors 1 and 4 as much as possible (for example, the vehicle is driven by supplying the maximum electric power that can be taken from the main battery 15 to the motors 1 and 4), and the shortage is covered by the output of the engine 2. It is an operating point. On the other hand, the point E is an operating point when the vehicle is driven by the engine 2 and the motors 1 and 4 are driven to generate power in order to increase the charge amount of the battery 15.
[0048]
If the fuel supply amount to the engine 2 is increased at the operating point A where the main battery 15 is discharged, the charge / discharge amount of the main battery 15 becomes 0 at the point N, and further points B → C → D → The charge amount of the main battery 15 increases in the order of E. Incidentally, as shown in FIG. 5, the charge amount at point B is c_b [kW], the charge amount at point C is c_c [kW], the charge amount at point D is c_d [kW], and the charge amount at point E is c_e [ kW].
[0049]
With reference to the fuel supply amount at the point A, the relationship between the charging power increase amount Δbat and the charging power Bat with respect to the fuel increase amount Δfuel is shown by a curve (1) in FIG. Further, the curve (2) is obtained from the curve (1) to obtain the ratio (= Δbat / Δfuel) of the charging power increase amount Δbat to the fuel increase amount Δfuel, and this ratio is called sensitivity S in this specification. These curves {circle around (1)} and {circle around (2)} are obtained in advance for each condition of vehicle speed and braking / driving force through experiments or the like.
[0050]
As shown in FIG. 5, the larger the SOC conversion index, the greater the sensitivity S is associated with. In this example, the sensitivity S is set to s170 for the SOC conversion index = 70%, the sensitivity S is set to s150 for the SOC conversion index = 50%, and the sensitivity S is set to s130 for the SOC conversion index = 30%. is doing.
[0051]
And the engine / motor operating point which implement | achieves the charging electric power Bat of the sensitivity S according to a SOC conversion parameter | index is calculated. For example, when the SOC conversion index is 70%, a point B1 satisfying the sensitivity S = s170 on the sensitivity curve {circle around (2)} is obtained, and a point B on the fuel supply amount curve {circle around (1)} realizing the sensitivity s170 is obtained. The point B in FIG. 4 corresponding to this point B may be set as the operating point of the engine 2 and the motors 1 and 4. In addition, when there are two points on the curve {circle around (2)} satisfying the sensitivity S, a point having a large charge power Bat is adopted. If the point satisfying the sensitivity S is not on the curve (2), that is, if there is no driving point that can be charged with the sensitivity S under the current vehicle speed and braking / driving force conditions, the points shown in FIG. A is an operating point of the engine 2 and the motors 1 and 4.
[0052]
The curves {circle around (1)} and {circle around (2)} differ depending on the conditions of the vehicle speed and the braking / driving force, so the maximum value of the sensitivity S also differs depending on the conditions of the vehicle speed and the braking / driving force. Therefore, when the SOC conversion index is large, an operating point that satisfies the sensitivity S can be obtained only under the conditions of the limited vehicle speed and braking / driving force. On the contrary, when the SOC conversion index is small, it is possible to take an operating point that satisfies the sensitivity S under a wide range of vehicle speed and braking / driving force conditions.
[0053]
Accordingly, the larger the SOC conversion index, the fewer the chances of charging the battery 15, and the smaller the SOC conversion index, the more the charging opportunities. Further, the larger the SOC conversion index, the higher the fuel utilization efficiency at the time of charging, and the smaller the SOC conversion index, the lower the fuel utilization efficiency at the time of charging execution.
[0054]
In the above description, the sensitivity S corresponding to the SOC conversion index is obtained, the charging power Bat for realizing the sensitivity S is obtained, and the engine / motor operating point corresponding to the charging power Bat is obtained. Data that associates the charging power Bat and the engine / motor operating point with respect to the conversion index may be stored, and the data may be read to obtain the charging power Bat and the engine / motor operating point. This facilitates the calculation of the engine / motor operating point.
[0055]
Further, with respect to the characteristic curve (1) in FIG. 5, taking into account the power consumption of the electrical components, the discharge efficiency of the main battery 15 when discharging to the left of the point N and the charging efficiency to the right of the point N are shown. It is good to relate in consideration of the charging efficiency of the main battery 15.
[0056]
The gear ratio of the continuously variable transmission 5 is adjusted to a gear ratio that realizes the vehicle speed and the rotational speed of the engine / motor operating point. Further, the torques of the motors 1 and 4 are distributed in advance, and a value that can realize the target braking / driving force command value by the motors 1, 4 and the engine 2 is calculated.
[0057]
The operating points of the clutch 3 are related in advance as shown in FIG. 6, and the engagement and release are controlled according to this relationship. When the clutch is disengaged, the rotational speeds of the engine 2 and the motor 1 coincide with each other, and the torque of the engine 2 and the converted value of the torque of the motor 1 around the engine shaft are constant. The operating points of the engine 2 and the motors 1 and 4 are determined by the method described with reference to FIG.
[0058]
In this embodiment, the above-described engine and motor operating point determination method is used to calculate the SOC conversion index, and conversely, the above-described SOC conversion index is used to determine the engine and motor operating points. If either one is not determined first, neither can be calculated. Therefore, as described above, in the calculation of the SOC conversion index SOCc, first, some value is set as the value of SOCc, in the above example, the initial value SOCc_0 is set to obtain a temporary operating point of the engine and the motor, and the SOC at the destination (p_SOC (N)) is predicted. Then, the calculation of the SOC conversion index SOCc is repeated until the predicted SOC (p_SOC (n)) at the destination matches the target SOC (t_SOC) using Formula 1 and Formula 2 using the predetermined value α, and the calculation converges Is determined as the final SOC conversion index SOCc.
[0059]
Then, actual operating points of the engine and the motor are determined based on the determined SOC conversion index SOCc. First, a braking / driving force command value d_tTd corresponding to the detected vehicle speed d_Vsp and the detected accelerator opening d_Acc is calculated from a table of braking / driving force command values set in advance based on the vehicle speed and the accelerator opening. Next, based on the SOC conversion index SOCc, the vehicle speed detection value d_Vsp, and the calculated value d_tTd of the braking / driving force command value, a formal operating point when the engine and the motor are traveling is determined. The engine 2 and the motors 1 and 4 are controlled at this operating point.
[0060]
As a result, the operating point of the engine 2 and the motors 1 and 4 is determined using the SOC conversion index SOCc in the guidance route to the destination, and the fuel consumption in the guidance route to the destination is minimized. While suppressing, the SOC of the main battery 15 at the destination can be set to the target value t_SOC.
[0061]
7 and 8 are flowcharts showing the vehicle control program, and the operation of the first embodiment will be described with reference to these flowcharts. The vehicle controller 16 executes this control program every predetermined time. In step 1, the current location is detected. In the second and subsequent executions, the position in the divided section way (i) (i = 1 to n) is also detected. In the following step 2, it is confirmed whether or not there is a new input or change of the destination, a departure from the guidance route, or a change in the traffic condition. If there is any, the process proceeds to step 3; Proceed to In addition, the change of the traffic situation is obtained by a road-to-vehicle communication device such as VICS.
[0062]
When there is any new input or change of the destination, deviation of the guidance route, or change of the traffic congestion state, the guidance route to the destination is searched in step 3. In subsequent step 4, the guidance route to the destination is divided into n sections way (i) (i = 1 to n). This route division method can be used to classify points with distinctive features in the road environment, such as slope change points, intersections, road type change points, traffic jam start points, traffic jam end points, expressway tollgates, etc. There is a method of dividing the distance to the destination into n equal parts.
[0063]
When the distance to the destination is long, the route may be divided using a passing point on the guidance route to the destination as a virtual destination. On the other hand, when the distance to the destination is shorter than a predetermined distance (for example, 10 km), a point on the substantially extension line passing through the destination with the predetermined distance from the current location is set as the virtual destination, and the destination and the virtual As a standard road environment in which the road environment of the destination is set in advance (an environment in which road types, congestion levels, and gradients are mixed), the route may be divided by regarding the virtual destination as the destination.
[0064]
In addition, when the distance to the destination is closer than a predetermined distance (for example, 10 km), the road environment, for example, the elevation of the destination and the elevation of the surrounding road is determined by the road environment data of the elevation stored in the navigation. In comparison, if the destination is higher than the surrounding road, it is likely that a downhill will continue after the destination passes, and a downhill (for example, 1km ahead of the destination is a slope between the destination and the virtual destination). -2% and 0% ahead), and if the destination is lower than the surrounding roads, it is likely that an uphill will continue after passing the destination. Is set as an uphill (for example, 1 km ahead of the destination is a gradient of 2% and 0% beyond that). In addition, route division may be performed by regarding the virtual destination as the destination.
[0065]
Further, not only the altitude but also the road type, the road type in the vicinity of the destination may continue even before the destination.
[0066]
In this way, when the distance to the destination is closer than the predetermined distance, the road environment between the destination and the virtual destination is set based on the road environment at the destination. If it is higher, the possibility that a downhill will continue after passing through the destination is high, and it is possible to estimate the downhill between the destination and the virtual destination and adjust the operating points of the engine and the motor. Thereby, the fuel-saving driving | operation becomes possible in consideration of the road environment ahead of the destination.
[0067]
In addition, as a method for determining the number of route divisions, there are a method for determining according to the degree of gradient change, the number of intersections, the road type, and a method for determining the number of divisions proportional to the distance to the destination.
[0068]
In step 5, road environment such as average gradient, intersection position, radius of curvature, altitude, etc. in each divided section way (i) is detected. In subsequent step 6, the target SOC (t_SOC) at the destination is determined to be a predetermined value (for example, 60%).
[0069]
In step 7, the vehicle speed p_Vsp (i) and the braking / driving force command value p_tTd (i) in each divided section way (i) between the current location and the destination are predicted based on the road environment of each divided section way (i). . The vehicle speed p_Vsp (i) is predicted as follows, for example. In the guidance route, the road speed limit is used as the predicted value. For example, a vehicle speed p_Vsp (i) that predicts a vehicle speed p_Vsp (i) such that the vehicle speed becomes 0 at a deceleration of 0.1G and returns to the cruising speed at an acceleration of 0.1G after 3 seconds of stopping at an intersection that makes a right or left turn. The vehicle speed p_Vsp (i) is predicted based on the acceleration / deceleration and the passing speed corresponding to the vehicle speed. Further, when traffic jam information is obtained from a road-to-vehicle communication device such as VICS, the vehicle speed p_Vsp (i) is predicted such that the average vehicle speed decreases as the traffic jam in the traffic jam section becomes worse. The braking / driving force command value p_tTd (i) of each divided section way (i) includes the driving force corresponding to the running resistance (air resistance component + rolling resistance component) corresponding to the vehicle speed p_vsp (i) and the speed of the previous section. A braking / driving force that is the sum of the braking / driving force corresponding to the acceleration / deceleration according to the difference and the braking / driving force corresponding to the acceleration / deceleration for absorbing the potential energy change of the vehicle according to the road gradient is set.
[0070]
When it is determined in step 14 that will be described later that the deviation between the prediction of the vehicle speed and the braking / driving force command value is large and step 7 is executed, the direction of deviation between the predicted value and the actual value is detected, and the direction of deviation is determined. Considering it, the vehicle speed p_Vsp (i) and the braking / driving force command value p-tTd (i) are re-predicted. For example, when the predicted vehicle speed p_Vsp (i) during traveling tends to be higher than the actual vehicle speed, the predicted vehicle speed p_Vsp (i) is set to a lower value, and the predicted braking / driving force command value p_tTd (i) during traveling is actually reduced. When it is smaller than the driving force command value, the predicted braking / driving force command value p_tTd (i) is set to a larger value. Alternatively, in the case of a route that the guidance route has taken before, the vehicle speed m_Vsp (i) of the route section when the route has passed previously may be set as the predicted vehicle speed p_Vsp (i), or the predicted vehicle speed p_Vsp (i). And an internal division value of the previous vehicle speed m_Vsp (i). However, in that case, it is necessary to store at least the vehicle speed m_Vsp (i) in the route section that the vehicle has traveled before.
[0071]
In step 8, the current SOC (d_SOC) is detected, and in the subsequent step 9, the SOC conversion index SOCc is calculated by the method described above. Further, the SOC conversion index SOCc may be corrected using the standard SOC conversion index value (standard control parameter) SOCcm. The standard SOC conversion index value SOCcm is a value that can maintain a predetermined SOC in a standard road environment, that is, an SOC conversion index in which the initial SOC and the final SOC substantially match when traveling in a typical road environment. This value is stored in advance using an experiment or simulation. Now, for convenience, the SOC conversion index SOCc calculated is set as SOC_00, SOC_00 is corrected to approach SOCcm, and the corrected value is set as the SOC conversion index SOCc.
[0072]
As a correction method of SOC_00 when the road to the destination is shorter than a predetermined distance (for example, 10 km), for example, there is a method of selecting the internal dividing points of SOC_00 and SOCcm according to the road Dx to the destination.
[0073]
[Equation 3]

[0074]
Further, when the road to the destination exceeds a predetermined distance (for example, 10 km), SOCcm = SOC_00 is set. When the standard SOC conversion index value SOCcm is used, the predicted SOC (p_SOC (i)) in the next step 10 uses the corrected SOC conversion index SOCc.
[0075]
Here, the relationship between step 4 and step 9 will be described with reference to FIG. In step 4, the virtual destination is set at a point 10 km ahead of the current position, for example, and the SOC conversion index SOCc is calculated so that the fuel consumption up to that point is suppressed. Based on the calculated value, the engine and motor operations are performed. The point is adjusted. The calculated SOCc corresponds to the SOC scheduling of (3). On the other hand, in step 9, the SOC conversion index calculated so that the SOC at the destination becomes the target SOC corresponds to the SOC scheduling of (1), and the standard SOC conversion index SOCcm is of (2). This is equivalent to SOC scheduling. These values have the following relationship: The SOC conversion index SOCc corresponding to the SOC scheduling in (3) is between the SOC conversion index calculated so that the SOC at the destination becomes the target SOC and the standard SOC conversion index SOCcm.
[0076]
That is, it can be said that it is the same as the control content performed in Step 4 by correcting the SOC conversion index calculated so that the SOC at the destination becomes the target SOC so as to approach the standard SOC conversion index SOCcm.
[0077]
Further, when the standard SOC conversion index value SOCcm is traveled in the road environment estimated based on the characteristics of the destination, the accuracy can be further improved if it is corrected and used as a value for maintaining the SOC. As a correction method, for example, the elevation of the destination and the elevation of the surrounding road are compared with the elevation data stored in the navigation, and the correction is performed based on the comparison result. If the altitude of the destination is higher than the altitudes of the surrounding roads, it is assumed that the downhill continues after passing through the destination and there is a high possibility that the regenerative energy can be recovered. On the other hand, if the altitude of the destination is lower than the altitude of the surrounding road, the uphill will continue after passing through the destination, and it is highly possible that kinetic energy is required. To do. If there is no difference in elevation between the destination and the surrounding road, the SOCcm is not corrected. By performing such control, fuel-saving driving is possible by considering the road environment ahead of the destination.
[0078]
In step 10, the SOC (p_SOC (i)) of each divided section way (i) is predicted based on the calculated SOC conversion index SOCc, the predicted vehicle speed p_Vsp (i), and the predicted braking / driving force command value p_tTd (i). To do. First, based on the SOC conversion index SOCc, the predicted vehicle speed p_Vsp (i), and the predicted braking / driving force command value p_tTd (i), as described above, the tentative of the engine 2 and the motors 1 and 4 in each divided section way (i). Is obtained, the predicted battery charge / discharge power p_Bat (i) in each divided section is obtained. Accordingly, when the current SOC (d_SOC) is used as an initial value and the estimated battery charge / discharge power p_Bat (i) of each divided section way (i) is time integrated, the SOC (p_SOC (i)) of each divided section way (i) is obtained. Can be predicted.
[0079]
In step 11, the vehicle speed d_Vsp is detected by the vehicle speed sensor 23, and in the subsequent step 12, the accelerator opening d_Acc is detected by the accelerator sensor 22. In step 13, a braking / driving force command value d_tTd corresponding to the detected vehicle speed d_Vsp and the detected accelerator opening d_Acc is calculated from a table of braking / driving force command values set in advance based on the vehicle speed and the accelerator opening.
[0080]
In step 14, at the end of each divided section way (i), for example, average vehicle speed d_Vsp (i) and average braking / driving force command value d_tTd (i), predicted vehicle speed p_Vsp (i) and predicted braking / driving force of each divided section. It is determined whether or not the deviation from the command value p_tTd (i) is larger than each predetermined value. If it is larger, the process returns to Step 7, and if it is smaller than the predetermined value, the process proceeds to Step 15.
[0081]
As an index of deviation, for example, there is a method in which the sum ERR_1 of the square error of the vehicle speed and the square error of the braking / driving force command value is used as an index.
[0082]
[Expression 4]

[0083]
In the above equation, K1 is a constant, and Σ represents the total sum in i from the time when the previous predicted value was updated to the present time.
[0084]
Further, there is a method in which the power error exerted on the vehicle has a high correlation with the fuel consumption and charge / discharge power noted in this embodiment, and the square error ERR_2 of the power equivalent value (vehicle speed × braking / driving force) is used as an index. .
[0085]
[Equation 5]

[0086]
In the above equation, Σ represents the sum in i from the time when the previous predicted value was updated to the present time. If it is determined that the prediction of the vehicle speed and the braking / driving force command value is large and the process proceeds from this step to step 7, the direction of deviation between the predicted value and the actual value is detected, and the direction of deviation is taken into consideration. In step 7, the vehicle speed p_Vsp (i) and the braking / driving force command value p_tTd (i) are re-predicted. For example, when the predicted vehicle speed p_Vsp (i) during traveling tends to be higher than the actual vehicle speed, the predicted vehicle speed p_Vsp (i) is set to a lower value, and the predicted braking / driving force command value p_tTd (i) during traveling is actually When it is smaller than the braking / driving force command value, the predicted braking / driving force command value p_tTd (i) is set to a larger value. Alternatively, in the case of a route that the guidance route has taken before, the vehicle speed pattern m_Vsp (i) of the route section when the route has passed previously may be used as the predicted vehicle speed p_Vsp (i), or the predicted vehicle speed p_Vsp (i). ) And the previous vehicle speed m_Vsp (i). However, in that case, it is necessary to store at least the vehicle speed m_Vsp (i) in the route section that the vehicle has traveled before.
[0087]
In step 15, it is determined whether or not the difference between the current SOC (d_SOC) and the predicted SOC (p_SOC (i)) is greater than a predetermined value at the end point of each divided section way (i). Returning to step 16, the process proceeds to step 16 if it is equal to or smaller than the predetermined value. As an index of deviation, for example, there is one as shown in the following equation.
[0088]
[Formula 6]

[0089]
In step 16, a formal operating point when the engine and the motor are running is calculated based on the convergence value SOCc_j of the SOC conversion index SOCc, the current vehicle speed detection value d_Vsp, and the calculated value d_tTd of the braking / driving force command value. At this time, when the detected SOC (d_SOC) is in the vicinity of the upper and lower limit values set in advance for protecting the main battery 15, priority is given to the protection of the battery 15, and the detected SOC (instead of the SOC conversion index SOCc) It is assumed that the calculation is performed using d_SOC). In the following step 17, the torque of the engine 2, the torques of the motors 1 and 4, the gear ratio of the continuously variable transmission 5, and the engagement / release of the clutch 3 are controlled so as to realize the engine / motor operating point.
[0090]
When the navigation device 33 is not operating or when the destination is not set, the steps 8 → 11 → 12 → 13 → 16 → 17 of the flowcharts shown in FIGS. 7 and 8 are executed in this order. However, when the destination is not set but the navigation device 33 is operating, it is detected that the vehicle is traveling on a commuting route that has traveled in the past or a route that travels well every day. For example, a destination such as a commuting destination or a supermarket may be specified from the traveling information, and step 3 and subsequent steps may be executed.
[0091]
In calculating the SOC conversion index SOCc, the predicted SOC (p_SOC (i)) of all the divided sections way (i) is calculated. Therefore, the predicted SOC (p_SOC (i)) in step 10 is calculated. As the value, the value of each divided section where SOCc = SOCc_j in step 9 may be used.
[0092]
Further, when the virtual destination is set and the SOC conversion index SOCc is used, and further when the standard SOC conversion index SOCcm is used, the predicted SOC (p_SOC (i)) in each divided section is set as the target SOC, and each section The operating point of the engine and the motor may be adjusted so as to adjust the charge / discharge amount of the battery so that the SOC matches the predicted SOC (p_SOC (i)). More specifically, when the SOC is smaller than the predicted SOC (p_SOC (i)), the output of the engine is increased, and the operating point of the engine and the motor is adjusted so as to increase the regenerative power of the motor. Increase charge. Conversely, if the SOC is greater than the predicted SOC (p_SOC (i)), the engine output is reduced and the engine and motor operating points are adjusted to reduce the regenerative power of the motor, thereby reducing the amount of discharge to the battery. Increase it. Thereby, in step 4, when the road to the destination is less than or equal to the predetermined distance, the virtual destination is set, and the SOC at the virtual destination is set as the target SOC, and the total fuel consumption to the virtual destination can be kept small. Thus, the target SOC to the virtual destination is scheduled (see FIG. 10). Therefore, it is possible to increase the probability that the total fuel consumption is suppressed in consideration of the vehicle travel state after the destination.
[0093]
Further, based on the road information and SOC on the guidance route from the departure point to the destination, the SOC conversion index SOCc is calculated so that the SOC at the virtual destination becomes the target SOC, and the engine and motor are based on the SOC conversion index SOCc. Since the operating point is determined, the total fuel consumption can be reduced.
[0094]
As described above, in the first embodiment, the guide route to the destination is divided, and the vehicle speed p_Vsp and the braking / driving force command value p_tTd in each divided section of the guide route are predicted based on the road environment information of the navigation. Based on the predicted vehicle speed p_Vsp of each divided section, the predicted braking / driving force command value p_tTd, and the SOC conversion index SOCc in which the initial value SOCc_0 of the battery SOC is set, the operating points of the engine and the motor with good fuel utilization efficiency are temporarily determined. Next, the SOC at the destination is predicted based on the temporary operation points of the engine and motor in each divided section and the current SOC detection value d_SOC, and the predicted SOC (p_SOC) at the destination is the target SOC (t_SOC) at the destination. The SOC conversion index SOCc is converged to the convergence value SOCc_j until it substantially coincides with. The braking / driving force command value d_tTd is calculated from a preset braking / driving force command value table based on the vehicle speed detection value d_Vsp and the accelerator opening detection value, and the vehicle speed detection value d_Vsp and the braking / driving force command value are calculated. Based on the value d_tTd and the convergence value SOCc_j of the SOC conversion index, final operating points of the engine and the motor are determined.
[0095]
According to the first embodiment, the SOC conversion index SOCc is introduced, the vehicle speed and the braking / driving force command value of the guidance route are predicted based on the road environment information detected by the navigation device, and ahead of the destination. The operating point of the engine and motor with good fuel utilization efficiency will be tentatively determined after consideration. Therefore, when the vehicle speed detection value to the destination and the calculated value of the braking / driving force command value match the predicted vehicle speed and the predicted braking / driving force command value, respectively, the fuel consumption can be suppressed to the minimum. Also, when actually driving with the engine and motor operating points determined, instead of the predicted vehicle speed and predicted braking / driving force command value, the official operating point is calculated using the calculated values of the vehicle speed detection value and braking / driving force command value. Since the calculation is performed, even when the predicted vehicle speed and the predicted braking / driving force command value deviate from the actual values, an operating point with poor fuel utilization efficiency is not selected, and the effect of reducing fuel consumption can be maintained.
[0096]
<< Second Embodiment >>
Another calculation method of the SOC conversion index SOCc will be described. The configuration of the second embodiment is the same as the configuration shown in FIGS. 1 and 2, and illustration and description thereof are omitted.
[0097]
FIG. 11 and FIG. 12 are flowcharts showing a vehicle control program including another calculation method of the SOC conversion index. The operation of the second embodiment will be described with reference to these flowcharts. Steps that perform the same operations as those shown in FIG. 7 and FIG. 8 are given the same step numbers, and differences will be mainly described.
[0098]
The vehicle controller 16 executes this control program every predetermined time. After the current location is detected in step 1, the current SOC (d_SOC) is detected in step 8. In the following step 2, as described above, it is confirmed whether there is a new input or change of the destination, a departure from the guidance route, or a change in the traffic situation. If any, the process proceeds to step 3 and there is nothing. If so, go to Step 11.
[0099]
When there is any new input or change of the destination, deviation of the guidance route, or change of the traffic congestion state, the guidance route to the destination is searched in step 3. Next, in step 4, as described above, the guidance route to the destination is divided into m sections way (j) (j = 1 to m), and each section way (j) is further divided into p sections. Is divided into n (= m · p) sections way (i) (i = 1 to n).
[0100]
When the distance to the destination is long, the route may be divided using a passing point on the guidance route to the destination as a virtual destination. On the other hand, when the distance to the destination is shorter than a predetermined distance (for example, 10 km), a point on the substantially extension line passing through the destination with the predetermined distance from the current location is set as the virtual destination, and the destination and the virtual As a standard road environment in which the road environment of the destination is set in advance (an environment in which road types, congestion levels, and gradients are mixed), the route may be divided by regarding the virtual destination as the destination. When the distance to the destination is shorter than a predetermined distance (for example, 10 km), a point at a predetermined distance from the current location is set as the virtual destination, and the road environment of the destination and the virtual destination is set as the destination. Set according to the surrounding road environment. Then, route division may be performed by regarding the virtual destination as the destination.
[0101]
In subsequent step 5, road environment such as average gradient, intersection position, radius of curvature, altitude, etc. in each divided section way (j) is detected. In subsequent step 6, the target SOC (t_SOC) at the destination is determined to be a predetermined value (for example, 60%).
[0102]
In step 21, the upper and lower limit values of the SOC corresponding to the road environment for each section way (j) are set in consideration of the power performance of the vehicle. For example, as shown in FIG. 13, when an uphill is expected to continue for 5 km from a certain section way (k) in the middle of the route, the section way ( The SOC lower limit value in k) is set to 50%, and when the uphill continues for 10 km, the SOC lower limit value is set to 60%.
[0103]
In principle, the upper and lower SOC limits of each divided section are 80% or less and 20% or more for battery protection as shown in FIG. Further, the upper and lower limit values of the SOC may be set over the entire section, or may be set for each section way (j). Furthermore, you may set with respect to the arbitrary points on a guidance route. Of course, only the upper limit value or only the lower limit value may be set.
[0104]
In step 7, as described above, the vehicle speed p_Vsp (i) and the braking / driving force command value p_tTd () in each divided section way (i) between the current position and the destination based on the road environment of each divided section way (j). i) is predicted. The vehicle speed p_Vsp (i) is predicted as follows, for example. In the guidance route, the speed limit of the section way (j) is set as the predicted value. In addition, at an intersection, level crossing, or toll gate that makes a right or left turn, for example, a vehicle speed p_Vsp (i) is predicted such that the vehicle speed becomes 0 at a deceleration of 0.1G and returns to the cruising speed at an acceleration of 0.1G after stopping for 3 seconds. In the curved road section, the vehicle speed p_Vsp (i) is predicted based on the acceleration / deceleration and the passing speed according to the curvature of the road. Further, when traffic jam information is obtained from a road-to-vehicle communication device such as VICS, the vehicle speed p_Vsp (i) is predicted such that the average vehicle speed decreases as the traffic jam in the traffic jam section becomes worse. On the other hand, the braking / driving force command value p_tTd (i) of each divided section way (i) includes a driving force corresponding to the running resistance (air resistance component + rolling resistance component) corresponding to the vehicle speed p_Vsp (i), The braking / driving force that is the sum of the braking / driving force corresponding to the acceleration / deceleration according to the speed difference and the braking / driving force corresponding to the acceleration / deceleration for absorbing the potential energy change of the vehicle according to the road gradient is set.
[0105]
In step 9, the SOC conversion index SOCc is calculated by the method described above in the first embodiment. In step 10, the SOC (p_SOC (i)) of each divided section way (i) is predicted based on the calculated SOC conversion index SOCc, the predicted vehicle speed p_Vsp (i), and the predicted braking / driving force command value p_tTd (i). To do. First, based on the SOC conversion index SOCc, the predicted vehicle speed p_Vsp (i), and the predicted braking / driving force command value p_tTd (i), as described above, the tentative of the engine 2 and the motors 1 and 4 in each divided section way (i). Is obtained, the predicted battery charge / discharge power p_Bat (i) in each divided section is obtained. Accordingly, when the current SOC (d_SOC) is set as an initial value and the predicted battery charge / discharge power p_Bat (i) of each divided section way (i) is time integrated, the SOC (p_SOC (i)) of each divided section way (i) is obtained. Can be predicted.
[0106]
In step 22, it is confirmed whether the SOC (p_SOC (i)) of each predicted divided section way (i) exceeds the upper and lower limit values set in step 21. If not, go to Step 11.
[0107]
When the SOC (p_SOC (i)) of each divided section way (i) does not exceed the upper and lower limit values set in step 21, and when the distance to the destination is a predetermined distance (for example, 10 km) or less, The calculated SOC conversion index value is set as SOC_00, and this SOC_00 is corrected so as to approach the standard SOC conversion index value SOCcm stored in advance in the controller 16, and the corrected value is set as the SOC conversion index value SOCc. Based on this value After calculating the predicted SOC (p_SOC (i)) to the destination, the process may proceed to step 11. The correction of SOC_00 at this time is based on the equation (6). At this time, when traveling in a road environment in which the standard SOC conversion index value SOCcm is estimated based on the characteristics of the destination, the accuracy can be further improved if it is used as a value for maintaining the SOC. The correction method is as described in Step 9.
[0108]
If the predicted SOC (p_SOC (i)) exceeds the upper and lower limit values, the SOC conversion index SOCc is corrected in step 23. For example, as shown in FIG. 14, when the predicted SOC (p_SOC (i)) exceeds the lower limit at the PA point on the way to the destination (1), it does not exceed the lower limit (2) The SOC conversion index SOCc is corrected by Equation 1 and is reduced to the line (1). On the contrary, when the predicted SOC (p_SOC (i)) exceeds the upper limit value, the SOC conversion index SOCc is corrected by Formula 2 to a point where it does not exceed the upper limit value. However, if both the upper limit value and the lower limit value are exceeded during the correction process, the SOC predicted value p_SOC (i) closer to the current location of the vehicle (the smaller value of i) is preferentially adopted, The SOC conversion index SOCc is corrected by Equation 1 or Equation 2 so as to be within the lower limit.
[0109]
Next, at step 24, the predicted SOC (p_SOC (i)) of each section way (i) falls within the SOC upper and lower limits, for example, the predicted SOC (p_SOC (i)) as shown in FIG. The point where the change curve is closest to the SOC upper / lower limit value or the intersection “PA” between the change curve of the predicted SOC (p_SOC (i)) and the SOC upper / lower limit value is stored. At this time, since the predicted SOC (p_SOC (n)) at the destination of the line (2) does not match the target SOC (t_SOC), if the SOC conversion index SOCc calculated in step 23 is used to the destination, the destination The actual SOC at does not match the target SOC (t_SOC). Therefore, the SOC conversion index SOCc calculated in step 23 is used until the vehicle reaches point PA, and after it is determined in step 26 described later that the vehicle has reached point PA, the SOC conversion index SOCc is determined in step 9. By recalculating and determining the driving point of the vehicle again based on the value, the actual SOC at the destination can be made substantially coincident with the target SOC (t_SOC).
[0110]
When there is no new input or change of the destination, departure from the guidance route, or change in the traffic congestion state, the vehicle speed d_Vsp is detected by the vehicle speed sensor 23 at step 11, and the accelerator opening d_Acc is detected by the accelerator sensor 22 at the next step 12. Is detected. In step 13, a braking / driving force command value d_tTd corresponding to the detected vehicle speed d_Vsp and the detected accelerator opening d_Acc is calculated from a table of braking / driving force command values set in advance based on the vehicle speed and the accelerator opening.
[0111]
In step 14, the average vehicle speed d_vsp (i) and the average braking / driving force command value d_tTd (i), the predicted vehicle speed p_Vsp (i), and the predicted braking / driving force command of each divided section at the end point of each divided section way (j). It is determined whether or not the deviation from the value p_tTd (i) is larger than each determination reference value. If it is larger, the process returns to Step 7 to calculate the predicted vehicle speed p_Vsp (i) and the predicted braking / driving force command value p_tTd (i). Recalculate. On the other hand, if the difference between the predicted value of the vehicle speed and the braking / driving force command value and the actual value is equal to or less than the determination reference value, the process proceeds to step 15. As the deviation index, the sum ERR_1 of the square error of the vehicle speed and the square error of the braking / driving force command value shown in Equation 3 is used, or the square error ERR_2 of the power equivalent value shown in Equation 4 is used. be able to. In step 15, it is determined whether or not the difference between the current SOC (d_SOC) and the predicted SOC (p_SOC (i)) is larger than the criterion value at the end point of each divided section way (i). Returning to 9, the SOC conversion index SOCc is recalculated. On the other hand, if the deviation between the predicted value and the actual value of the SOC is equal to or smaller than the determination reference value, the process proceeds to step 25. Note that, for example, ERR_3 shown in Equation 5 can be used as the deviation index.
[0112]
When the difference between the vehicle speed, the braking / driving force command value, and the predicted value of SOC and the actual value is small, the difference between the current SOC (d_SOC) in step 25 and the SOC upper and lower limit values set in step 21 is less than or equal to a predetermined value δSOC. Check whether or not. Here, an appropriate value for determining that the SOC has approached the upper and lower limit values is set as the predetermined value δSOC. When the current SOC approaches the upper and lower limit values, the process returns to step 9 to recalculate the SOC conversion index SOCc. On the other hand, when the current SOC is not close to the upper and lower limit values, the routine proceeds to step 26, where it is confirmed whether or not the vehicle has reached the point PA. Here, the point PA is a point where the current SOC (d_SOC) reaches the SOC upper and lower limit values set in step 21. When the point PA is reached, the process returns to step 9 to recalculate the SOC conversion index SOCc. On the other hand, if the point PA has not been reached, the process proceeds to step 16.
[0113]
In step 16, a formal operating point when the engine and the motor are traveling is calculated based on the convergence value SOCc_j of the SOC conversion index SOCc, the current vehicle speed detection value d_Vsp, and the calculated value d_tTd of the braking / driving force command value. In the following step 17, the torque of the engine 2, the torques of the motors 1 and 4, the gear ratio of the continuously variable transmission 5, and the engagement / release of the clutch 3 are controlled so as to realize the engine / motor operating point.
[0114]
Similarly to the first embodiment, the predicted SOC (p_SOC (i)) in each divided section is set as the target SOC, and the engine and the motor are set so that the SOC matches the predicted SOC (p_SOC (i)) in each section. The amount of charge / discharge of the battery may be adjusted by adjusting the operating point.
[0115]
As described above, in the second embodiment, the upper and lower limit values of the SOC corresponding to the road environment for each section way (i) are set in consideration of the power performance of the vehicle, and the SOC conversion index SOCc and each section way are set. The predicted SOC (p_SOC (i)) of (i) is calculated. When the predicted SOC (p_SOC (i)) of each section way (i) exceeds the upper and lower limit values of the SOC, the SOC conversion index SOCc is recalculated so as to be within the upper and lower limit values. The point where the change curve of the predicted SOC (p_SOC (i)) in the section way (i) is closest to the SOC upper / lower limit value, or the intersection PA of the change curve of the predicted SOC (p_SOC (i)) and the SOC upper / lower limit value is Remember. When the engine / motor operating point is determined based on the SOC conversion index SOCc and the vehicle is running, if the current SOC (d_SOC) approaches the SOC upper or lower limit value or reaches the point PA, the subsequent SOC conversion index The SOCc is recalculated, the engine / motor operating point is determined based on the new SOC conversion index SOCc, and the vehicle continues to travel to the destination. As a result, the vehicle can be driven efficiently while considering not only the destination but also beyond the destination.
[0116]
<< Third Embodiment >>
Another calculation method of the SOC conversion index SOCc will be described. The configuration of the third embodiment is basically the same as the configuration shown in FIGS. 1 and 2, but in the third embodiment, the vehicle speed and braking / driving force of each divided section to the destination are as follows. The traveling condition prediction function 16a (see FIG. 2) for predicting the command value is unnecessary.
[0117]
15 and 16 are flowcharts showing a vehicle control program including another calculation method of the SOC conversion index. The operation of the third embodiment will be described with reference to these flowcharts. Steps that perform the same operations as those shown in FIG. 7 and FIG. 8 are given the same step numbers, and differences will be mainly described.
[0118]
The vehicle controller 16 executes this control program every predetermined time. In step 1, the current location is detected. In the following step 2, it is confirmed whether or not there is a new input or change of the destination, a departure from the guidance route, or a change in the traffic condition. If there is any, the process proceeds to step 3; Proceed to When there is any new input or change of the destination, deviation of the guidance route, or change of the traffic congestion state, the guidance route to the destination is searched in step 3. In the subsequent step 4, as described above, the guidance route to the destination is divided into m sections way (j) (j = 1 to m) using the characteristic points in the road environment as the dividing points.
[0119]
When the distance to the destination is long, the route may be divided using a passing point on the guidance route to the destination as a temporary destination. On the other hand, when the distance to the destination is shorter than a predetermined distance (for example, 10 km), a point on the substantially extended line passing through the destination of the predetermined distance from the current location is set as the virtual destination, and the destination and the virtual As a standard road environment in which the road environment of the destination is set in advance (an environment in which road types, congestion levels, and gradients are mixed), the route may be divided by regarding the virtual destination as the destination. When the distance to the destination is shorter than a predetermined distance (for example, 10 km), a point at a predetermined distance from the current location is set as the virtual destination, and the road environment of the destination and the virtual destination is set as the destination. Set according to the surrounding road environment. Then, route division may be performed by regarding the virtual destination as the destination.
[0120]
In step 5, road environment such as average gradient, intersection position, curvature radius, altitude, etc. in each divided section way (j) is detected, and in step 6, target SOC (t_SOC) at the destination is a predetermined value (for example, 60%). To decide.
[0121]
Next, in step 8, the current SOC (d_SOC) is detected, and in the following step 31, the SOC conversion index SOCc is calculated as follows. First, a driving pattern is assumed for each road environment, and these driving patterns are stored in advance in a memory as SOC change amount data (MAP2D_SOC) per unit distance when driving with the SOC conversion index SOCc. Then, the SOC change amount p_d_SOC (j) corresponding to the SOC conversion index SOCc and the road environment for each section way (j) is calculated from this data (MAP2D_SOC), and the current SOC (d_SOC) is used as an initial value. By integrating the SOC change amount p_d_SOC (j) of each section way (j), the predicted SOC (p_SOC (j)) of each section way (j) and the predicted SOC (p_SOC (m)) at the destination are obtained. This calculation is performed until the predicted SOC (p_SOC (m)) at the destination substantially matches the target SOC (t_SOC) at the destination, and the SOC conversion index when both are almost matched is set as the final index SOCc. .
[0122]
Alternatively, the SOC conversion index SOCc may be corrected using the standard SOC conversion index value SOCcm. The standard SOC conversion index value SOCcm is a value that can maintain the SOC in a standard road environment, that is, an SOC conversion index value in which the initial SOC and the final SOC substantially match when traveling in a typical road environment. Yes, pre-stored in the controller using experiments or simulations. Now, for convenience, the SOC conversion index SOCc calculated is set as SOC_00, SOC_00 is corrected to approach SOCcm, and the corrected value is set as the SOC conversion index SOCc.
[0123]
As a correction method of SOC_00 when the road to the destination is shorter than a predetermined distance (for example, 10 km), for example, there is a method of selecting the internal dividing points of SOC_00 and SOCcm according to the road Dx to the destination.
[0124]
[Formula 6]

[0125]
Further, when the road to the destination exceeds a predetermined distance (for example, 10 km), SOCcm = SOC_00 is set. When the standard SOC conversion index value SOCcm is used, the predicted SOC (p_SOC (i)) in the next step 10 uses the corrected SOC conversion index SOCc.
[0126]
Further, when traveling in a road environment in which the standard SOC conversion index value SOCcm is estimated based on the characteristics of the destination, it is possible to further improve the accuracy by using the corrected SOC value as shown in step 9 as a value for maintaining the SOC. .
[0127]
In step 11, the vehicle speed d_Vsp is detected by the vehicle speed sensor 23, and in the subsequent step 12, the accelerator opening d_Acc is detected by the accelerator sensor 22. In step 13, a braking / driving force command value d_tTd corresponding to the detected vehicle speed d_Vsp and the detected accelerator opening d_Acc is calculated from a braking / driving force command value table set in advance based on the vehicle speed and the accelerator opening.
[0128]
In step 32, it is determined whether or not the error of the SOC change amount (p_d_SOC (j)) in each section way (j) is large. That is, for each end point of each section way (j), the actual SOC change amount (d_d_SOC (k)) of the section way (k) passed immediately before is compared with the calculated SOC change amount p_d_SOC (k). If is large, correct it. For example, a value ERR4 obtained by the following equation can be used as the deviation determination reference value.
[0129]
[Expression 7]

[0130]
If the deviation is large, the process returns to step 8 to recalculate the SOC conversion index SOCc. If the deviation is small, the process proceeds to step 15.
[0131]
In step 15, it is determined whether or not the difference between the current SOC (d_SOC) and the predicted SOC (p_SOC (i)) is larger than the determination reference value at the end point of each divided section way (j). Returning to step 9, the process proceeds to step 16 if it is equal to or smaller than the determination reference value. As the determination reference value, the reference value ERR_3 can be used in Equation 3 above. As an index of deviation shown, for example, there is the one shown in the following equation.
[0132]
In step 16, a formal operating point when the engine and the motor are running is calculated based on the convergence value SOCc_j of the SOC conversion index SOCc, the current vehicle speed detection value d_Vsp, and the calculated value d_tTd of the braking / driving force command value. At this time, when the detected SOC (d_SOC) is in the vicinity of the upper and lower limit values set in advance for protecting the main battery 15, priority is given to the protection of the battery 15, and the detected SOC (instead of the SOC conversion index SOCc) It is assumed that the calculation is performed using d_SOC). In the following step 17, the torque of the engine 2, the torques of the motors 1 and 4, the gear ratio of the continuously variable transmission 5, and the engagement / release of the clutch 3 are controlled so as to realize the engine / motor operating point.
[0133]
Similarly to the first embodiment, the predicted SOC (p_SOC (i)) in each divided section is set as the target SOC, and the engine and the motor are set so that the SOC matches the predicted SOC (p_SOC (i)) in each section. The amount of charge / discharge of the battery may be adjusted by adjusting the operating point.
[0134]
The road environment information, SOC conversion index, and SOC change amount of the travel route are stored, and the SOC change amount for each section way (j) is predicted in consideration of the data of the past travel route. Good. Thereby, it is possible to predict the SOC change amount for each more accurate section way (j).
[0135]
As described above, according to the third embodiment, assuming the driving patterns for each road environment, the SOC change amount data per unit driving distance when the driving patterns are driven with various SOC conversion indexes are stored in advance. Store in memory. Then, the SOC change amount p_d_SOC (j) corresponding to the SOC conversion index SOCc and the road environment for each section way (j) is calculated from the SOC change amount data per unit travel distance, and the current SOC ( By integrating the SOC change amount p_d_SOC (j) of each section way (j) using d_SOC) as an initial value, the predicted SOC (p_SOC (j)) of each section way (j) and the predicted SOC at the destination (p_SOC (p m)). This calculation is executed until the predicted SOC (p_SOCm) at the destination substantially coincides with the target SOC (t_SOC) at the destination, and the SOC conversion index when both are almost coincident is set as the final index SOCc. The actual SOC change amount d_d_SOC (k) and the calculated SOC change amount p_d_SOC (k) in each section way (k) when the engine / motor operating point is determined based on the SOC conversion index SOCc. If the deviation is large, the SOC conversion index (SOC) is corrected. Further, in each section way (j), the current SOC (d_SOC) is compared with the predicted SOC (p_SOC (i)), and when the deviation is larger than the determination reference value, the SOC conversion index (SOC) is corrected. As a result, while improving the fuel utilization efficiency to the destination, the vehicle can be operated efficiently while considering not only the destination but also the destination.
[0136]
In the above embodiment, the ratio (Δbat / Δfuel) of the charging power increase amount Δbat to the fuel increase amount Δfuel, that is, the sensitivity S is used as the SOC conversion index, but the SOC conversion index is not limited to the sensitivity S. For example, for a hybrid vehicle that controls power generation when the SOC is low and suppresses power generation when the SOC is high, the SOC itself may be used as the SOC conversion index. In this case, when there is a downhill of a predetermined distance or more on the traveling path of the vehicle, the target SOC may be corrected to be smaller than the detected SOC. Further, the SOC correction amount may be increased as the difference between the SOC detection value and the target SOC at the destination is larger.
[0137]
Further, in the present embodiment, the description has been made using the SOC indicating the state of charge of the battery. However, the present invention is not limited to this, and any device that indicates the state of charge of the battery may be used. For example, DOD may be used.
[0138]
Note that in the braking / driving force automatic adjustment system that automatically adjusts the braking / driving force of the vehicle according to the situation on behalf of the driver, the “accelerator opening” in the above-described embodiment is controlled by the braking / driving force automatic adjustment system. By replacing the driving force command value, it is possible to obtain the same effect as that of the above-described embodiment.
[0139]
Further, in the above-described embodiment, the parallel hybrid traveling is realized by engaging the clutch 3, and the application example to the vehicle that also performs the series hybrid traveling by releasing the clutch 3 is shown. Alternatively, the present invention can be similarly applied to a vehicle that performs only series / hybrid driving.
[0140]
Furthermore, in the above-described embodiment, the continuously variable transmission has been described as an example. However, the transmission is not limited to the continuously variable transmission, and may be a stepped transmission. Further, the arrangement of the transmission is not limited to the above-described embodiment.
[0141]
Furthermore, the present invention can be applied to vehicles of all drive systems such as front wheel drive, rear wheel drive, and four wheel drive, and all forms of driving front wheels with an engine and driving rear wheels with a motor. It can be applied to a vehicle having a drive source form.
[0142]
Of course, the present invention can be similarly applied to a hybrid system having a planetary gear and having a mechanism capable of freely operating the engine and the motor.
[0143]
Such a hybrid system includes, for example, a system (Toyota Hybrid System) in which an engine is connected to a planetary carrier of a planetary gear, a power generation motor is connected to a sun gear, and a vehicle drive motor is connected to a ring gear. In the above-described embodiment, the operation rotational speeds of the engine and the motor have been shown to be applied to a system that can be adjusted by adjusting the gear ratio of the continuously variable transmission. In such a hybrid system, the planetary gear is used. In view of this characteristic, the present invention can be applied as a system that can adjust the operating rotational speed of the engine and the motor by adjusting the rotational speed of the power generation motor based on the same concept as the embodiment.
[0144]
Of course, the present invention can be similarly applied to a hybrid system including other planetary gears. For example, FIGS. 17 and 18 show a configuration having two sets of planetary gear mechanisms. In this mechanism, the difference between the engine and the motor can be adjusted by adjusting the rotational speed of the motor 1 (MG1 shown) or the motor 2 (MG2 shown). The dynamic rotational speed can be adjusted, and the present invention can be applied based on the same concept as the embodiment.
[0145]
The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea of the present invention.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an embodiment.
FIG. 2 is a diagram showing the configuration of the same embodiment.
FIG. 3 is a diagram for explaining a method of calculating an SOC conversion index.
FIG. 4 is a diagram showing operating points of the engine.
FIG. 5 is a diagram showing a charging power increase amount δbat, charging power Bat, and sensitivity S with respect to an engine fuel increase amount Δfuel;
FIG. 6 is a map for setting an operating point of a clutch.
FIG. 7 is a flowchart showing a vehicle control program according to the first embodiment.
FIG. 8 is a flowchart showing a vehicle control program.
FIG. 9 is a diagram for explaining the operation of claim 4;
FIG. 10 is a diagram for explaining the operation of claim 1;
FIG. 11 is a flowchart showing a vehicle control program according to the second embodiment.
FIG. 12 is a flowchart showing the vehicle control program.
FIG. 13 is a diagram for explaining a method for setting an SOC upper and lower limit value;
FIG. 14 is a diagram for explaining a method of correcting an SOC conversion index.
FIG. 15 is a flowchart illustrating a vehicle control program according to a third embodiment.
FIG. 16 is a flowchart showing a vehicle control program.
FIG. 17 is a diagram illustrating another hybrid system to which the present invention can be applied.
FIG. 18 is a diagram illustrating another hybrid system to which the present invention can be applied.
FIG. 19 is a diagram illustrating a problem of a conventional method.
[Explanation of symbols]
1 Motor
2 Engine
4 Motor
5 continuously variable transmission
9 Hydraulic system
10 Motor
11 Inverter
12 Inverter
13 Inverter
15 battery
16 controller
23 Vehicle speed sensor
25 SOC sensor
33 Navigation device

Claims (5)

An engine and a motor as braking / driving sources;
In a control apparatus for a hybrid vehicle including a battery that transmits and receives electric power to and from a motor,
Vehicle speed detection means for detecting the speed of the vehicle;
Braking / driving force command value detecting means for detecting a braking / driving force command value for the vehicle;
Storage state detection means for detecting a storage state of the battery;
A navigation device that stores a map including road information, identifies a current position of the vehicle on the map, and estimates a vehicle travel route to a destination;
A virtual destination setting means for setting a position far from the destination as a virtual destination when the distance to the destination is closer than a predetermined value;
First target power storage state setting means for setting a target power storage state at the virtual destination when traveling from the current position to the virtual destination;
Second target power storage state control means for setting a target power storage state to the virtual destination so that fuel consumption to the virtual destination is reduced when the distance to the destination is less than a predetermined value;
Based on the vehicle speed detection value, the braking / driving force command value, and the storage state, an operating point determination unit that determines the operating point of the engine and the motor so as to be the set target storage state,
Engine operating point adjusting means for adjusting the operating point of the engine based on the determined operating point;
Motor operating point adjusting means for adjusting the operating point of the motor based on the determined operating point;
A control apparatus for a hybrid vehicle, comprising: An engine and a motor as braking / driving sources;
In a control apparatus for a hybrid vehicle including a battery that transmits and receives electric power to and from a motor,
Vehicle speed detection means for detecting the speed of the vehicle;
Braking / driving force command value detecting means for detecting a braking / driving force command value for the vehicle;
Storage state detection means for detecting a storage state of the battery;
A navigation device that stores a map including road information, identifies a current position of the vehicle on the map, and estimates a vehicle travel route to a destination;
A virtual destination setting means for setting a position far from the destination as a virtual destination when the distance to the destination is less than a predetermined value;
Target power storage state setting means for setting a target power storage state at the virtual destination when traveling from the current position to the virtual destination;
The lower the power storage state, the higher the amount of charge to the battery, and the control parameters associated with the engine and motor operating points with poor engine fuel consumption efficiency. Based on the control parameter calculation means for calculating the control parameter so that the power storage state at the virtual destination becomes the target power storage state;
Driving point determination means for determining driving points of the engine and the motor based on the vehicle speed detection value, the braking / driving force command value, and the control parameter;
Engine operating point adjusting means for adjusting the operating point of the engine based on the determined operating point;
Motor operating point adjusting means for adjusting the operating point of the motor based on the determined operating point;
A control apparatus for a hybrid vehicle, comprising: The virtual destination setting means sets the road environment between the destination and the virtual destination according to the road environment of the destination when the distance to the destination is less than a predetermined value. The control apparatus of the hybrid vehicle as described in 1 or 2. An engine and a motor as braking / driving sources;
In a control apparatus for a hybrid vehicle including a battery that transmits and receives electric power to and from a motor,
Vehicle speed detection means for detecting the speed of the vehicle;
Braking / driving force command value detecting means for detecting a braking / driving force command value for the vehicle;
Storage state detection means for detecting a storage state of the battery;
A navigation device that stores a map including road information, identifies a current position of the vehicle on the map, and estimates a vehicle travel route to a destination;
Target power storage state setting means for setting a target power storage state at the virtual destination when traveling from the current position to the virtual destination;
The lower the power storage state, the higher the amount of charge to the battery, and the control parameters associated with the engine and motor operating points with poor engine fuel consumption efficiency. Based on the control parameter calculation means for calculating the control parameter so that the power storage state at the virtual destination becomes the target power storage state;
In a standard road environment, standard control parameter calculation means for setting a standard control parameter as a value capable of maintaining a predetermined power storage state;
Control parameter correction means for correcting the control parameter to be close to a standard parameter when the distance to the destination is less than a predetermined value;
Driving point determination means for determining driving points of the engine and the motor based on the vehicle speed detection value, the braking / driving force command value, and the control parameter;
Engine operating point adjusting means for adjusting the operating point of the engine based on the determined operating point;
Motor operating point adjusting means for adjusting the operating point of the motor based on the determined operating point;
A control apparatus for a hybrid vehicle, comprising: 5. The power storage state conversion index value setting unit sets a standard power storage state conversion index value as a value capable of maintaining a power storage state when traveling in a road environment estimated based on characteristics of a destination. The control apparatus of the hybrid vehicle as described in 2.

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