JP2004312944A - Drive controller of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance stability during straight driving by a simple means even in the case of a vehicle where left and right wheels are driven through individual drive motors. <P>SOLUTION: Motors 4RL and 4RR for driving left and right wheels 3L and 3R, respectively, are provided. These two drive motors 4RL and 4RR are driven with electric power from a generator 7 which is driven through an engine. The two drive motors 4RL and 4RR and the generator 7 are connected electrically in series. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

ここで、
Ｖ ：発電機７の電圧
Ｉａ：発電機７の電機子電流
Ｎｈ：発電機７の回転数
Ｋ３：効率
Ｋ２：係数
である。
ステップＳ６０では、下記式に基づき、余剰トルクつまり発電機７で負荷すべき目標の発電負荷トルクＴｈを求め、復帰する。
【００２６】
Ｔｈ ＝ ＴＧ ＋ ＴΔＶＦ
次に、目標トルク制限部８Ｆの処理について、図６に基づいて説明する。
すなわち、まず、ステップＳ１１０で、上記目標発電負荷トルクＴｈが、発電機７の最大負荷容量ＨＱより大きいか否かを判定する。目標発電負荷トルクＴｈが当該発電機７の最大負荷容量ＨＱ以下と判定した場合には、復帰する。一方、目標発電負荷トルクＴｈが発電機７の最大負荷容量ＨＱよりも大きいと判定した場合には、ステップＳ１２０に移行する。
【００２７】
ステップＳ１２０では、目標の発電負荷トルクＴｈにおける最大負荷容量ＨＱを越える超過トルクΔＴｂを下記式によって求め、ステップＳ１３０に移行する。
ΔＴｂ＝ Ｔｈ − ＨＱ
ステップＳ１３０では、エンジン回転数検出センサ２１及びスロットルセンサからの信号等に基づいて、現在のエンジントルクＴｅを演算してステップＳ１４０に移行する。
【００２８】
ステップＳ１４０では、下記式のように、上記エンジントルクＴｅから上記超過トルクΔＴｂを減算したエンジントルク上限値ＴｅＭを演算し、求めたエンジントルク上限値ＴｅＭをエンジンコントローラ１８に出力した後に、ステップＳ１５０に移行する。
ＴｅＭ ＝Ｔｅ −ΔＴｂ
ステップＳ１５０では、目標発電負荷トルクＴｈに最大負荷容量ＨＱを代入した後に、復帰する。
【００２９】
次に、余剰トルク変換部８Ｇの処理について、図７に基づいて説明する。
なお、この余剰トルク変換部８Ｇの処理の全部若しくは１部の処理については、駆動モータ毎に個別に実施しても良い。
まず、ステップＳ２００で、Ｔｈが０より大きいか否かを判定する。Ｔｈ＞０と判定されれば、前輪１Ｌ、１Ｒが加速スリップしているので、ステップＳ２２０に移行する。また、Ｔｈ≦０と判定されれば、前輪１Ｌ、１Ｒは加速スリップしていない状態であるので、そのまま復帰する。
【００３０】
次に、ステップＳ２２０では、駆動モータ用回転数センサ２１が検出した駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍを入力し、その駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍに応じた目標駆動モータ界磁電流Ｉｆｍを算出し、当該目標駆動モータ界磁電流Ｉｆｍを電動モータ制御部８Ｃに出力した後、ステップＳ２３０に移行する。
【００３１】
ここで、上記駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍに対する目標駆動モータ界磁電流Ｉｆｍは、回転数Ｎｍが所定回転数以下の場合には一定の所定電流値とし、駆動モータ４ＲＬ、４ＲＲが所定の回転数以上になった場合には、公知の弱め界磁制御方式で駆動モータ４ＲＬ、４ＲＲの界磁電流Ｉｆｍを小さくする。すなわち、駆動モータ４ＲＬ、４ＲＲが高速回転になると駆動モータ４ＲＬ、４ＲＲの誘起電圧Ｅの上昇により駆動モータトルクが低下することから、上述のように、駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍが所定値以上になったら駆動モータ４ＲＬ、４ＲＲの界磁電流Ｉｆｍを小さくして誘起電圧Ｅを低下させることで駆動モータ４ＲＬ、４ＲＲに流れる電流を増加させて所要駆動モータトルクを得るようにする。この結果、駆動モータ４ＲＬ、４ＲＲが高速回転になっても駆動モータ４ＲＬ、４ＲＲの誘起電圧Ｅの上昇を抑えて駆動モータトルクの低下を抑制するため、所要の駆動モータトルクを得ることができる。また、駆動モータ界磁電流Ｉｆｍを所定の回転数未満と所定の回転数以上との２段階で制御することで、連続的な界磁電流制御に比べ制御の電子回路を安価にできる。
【００３２】
なお、所要の駆動モータトルクに対し駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍに応じて界磁電流Ｉｆｍを調整することで駆動モータトルクを連続的に補正する駆動モータトルク補正手段を備えても良い。すなわち、２段階切替えに対し、駆動モータ４ＲＬ、４ＲＲの回転数Ｎｍに応じて駆動モータ４ＲＬ、４ＲＲの界磁電流Ｉｆｍを調整すると良い。この結果、駆動モータ４ＲＬ、４ＲＲが高速回転になっても駆動モータ４ＲＬ、４ＲＲの誘起電圧Ｅの上昇を抑え駆動モータトルクの低下を抑制するため、所要の駆動モータトルクを得ることができる。また、なめらかな駆動モータトルク特性にできるため、２段階制御に比べ車両は安定して走行できるし、常に駆動モータ４ＲＬ、４ＲＲの駆動効率が良い状態にすることができる。
【００３３】
次に、ステップＳ２３０では、上記余剰トルク演算部８Ｅが演算した発電負荷トルクＴｈに基づきマップなどから対応する目標駆動モータトルクＴｍ（ｎ）を算出して、ステップＳ２４０に移行する。
ステップＳ２４０では、上記目標駆動モータトルクＴｍ（ｎ）及び目標駆動モータ界磁電流Ｉｆｍを変数として、マップなどに基づき、対応する目標電機子電流Ｉａを求め、ステップＳ３１０に移行する。
【００３４】
ステップＳ３１０では、上記目標電機子電流Ｉａに基づき、発電機制御指令値であるデューティ比ｃ１を演算し出力した後に、復帰する。
次に、モータ制御部８Ｃの処理を説明する。モータ制御部８Ｃでは、余剰トルク変換部８Ｇが求めた目標駆動モータ界磁電流Ｉｆｍとなるように、２台の駆動モータ４ＲＬ、４ＲＲの界磁電流をそれぞれ調整することで、当該駆動モータ４ＲＬ、４ＲＲのトルクを所要の値に調整する。
【００３５】
次に、エンジンコントローラ１８の処理について説明する。
エンジンコントローラ１８では、所定のサンプリング時間毎に、入力した各信号に基づいて図８に示すような処理が行われる。
すなわち、まずステップＳ６１０で、アクセルセンサ４０からの検出信号に基づいて、運転者の要求する目標出力トルクＴｅＮを演算して、ステップＳ６２０に移行する。
【００３６】
ステップＳ６２０では、４ＷＤコントローラ８から制限出力トルクＴｅＭの入力があるか否かを判定する。入力が有ると判定するとステップＳ６３０に移行する。一方、入力が無いと判定した場合にはステップＳ６７０に移行する。
ステップＳ６３０では、目標出力トルクＴｅＮが制限出力トルクＴｅＭよりも大きいか否かを判定する。制限出力トルクＴｅＭよりも目標出力トルクＴｅＮの方が大きいと判定した場合には、ステップＳ６４０に移行する。一方、制限出力トルクＴｅＭの方が大きいか目標出力トルクＴｅＮと等しければステップＳ６７０に移行する。
【００３７】
ステップＳ６４０では、目標出力トルクＴｅＮに制限出力トルクＴｅＭを代入することで目標出力トルクＴｅＮを減少して、ステップＳ６７０に移行する。
ステップＳ６７０では、スロットル開度やエンジン回転数などに基づき、現在の出力トルクＴｅを算出してステップＳ６８０に移行する。
ステップＳ６８０では、現在の出力トルクＴｅに対する目標出力トルクＴｅＮのの偏差分ΔＴｅ′を下記式に基づき出力して、ステップＳ６９０に移行する。
【００３８】
ΔＴｅ′ ＝ＴｅＮ − Ｔｅ
ステップＳ６９０では、その偏差分ΔＴｅに応じたスロットル開度θの変化分Δθを演算し、その開度の変化分Δθに対応する開度信号を上記ステップモータ１９に出力して、復帰する。
次に、上記構成の装置における作用などについて説明する。
【００３９】
路面μが小さいためや運転者によるアクセルペダル１７の踏み込み量が大きいなどによって、エンジン２から前輪１Ｌ、１Ｒに伝達されたトルクが路面反力限界トルクよりも大きくなると、つまり、主駆動輪である前輪１Ｌ、１Ｒが加速スリップすると、各クラッチ１２ＲＬ、１２ＲＲが接続されると共に、その加速スリップ量に応じた発電負荷トルクＴｈで発電機７が発電することで、４輪駆動状態に移行する。続いて、前輪１Ｌ、１Ｒに伝達される駆動トルクが、当該前輪１Ｌ、１Ｒの路面反力限界トルクに近づくように調整されることで、２輪駆動状態に移行する。この結果、主駆動輪である前輪１Ｌ、１Ｒでの加速スリップが抑えられる。
【００４０】
しかも、発電機７で発電した余剰の電力によって駆動モータ４ＲＬ、４ＲＲが駆動されて従駆動輪である後輪３Ｌ、３Ｒも駆動されることで、車両の加速性が向上する。
このとき、主駆動輪１Ｌ、１Ｒの路面反力限界トルクを越えた余剰のトルクで駆動モータ４ＲＬ、４ＲＲを駆動するため、エネルギー効率が向上し、燃費の向上に繋がる。
【００４１】
４輪駆動状態となったときに、共通の電源である発電機７から左右の駆動モータ４ＲＬ、４ＲＲに対して電機子電流が供給されるが、図３に示すように、発電機７に対して左右の駆動モータ４ＲＬ、４ＲＲが直列に接続されている結果、左右の駆動モータ４ＲＬ、４ＲＲの電機子電流が同じとなり、当該左右の駆動モータ４ＲＬ、４ＲＲの駆動トルクが同じ値に、さらには、その各駆動モータ４ＲＬ、４ＲＲに駆動される左右輪で発生する駆動力が同じ値になる。この結果、左右後輪３Ｌ、３Ｒが個別にモータで駆動される車両であっても、車両の直進走行時の安定性が向上する。
【００４２】
また、左右の駆動モータ４ＲＬ、４ＲＲは、それぞれ対応する車輪の近傍に配置される結果、つまり、車両中央部に２台の駆動モータ４ＲＬ、４ＲＲを配置しない結果、車体後側のフロアを下げてフロアスペースを大きくする効果も有する。
もっとも、従来例のように、左右の駆動モータ４ＲＬ、４ＲＲを車幅方向中央部に配置してもよい。
【００４３】
ここで、上記実施形態では、前輪が加速スリップした場合に後輪３Ｌ、３Ｒを駆動する構成で説明しているが、アクセル開度などに応じて４輪駆動状態に移行するシステムであっても適用可能である。また、４ＷＤスイッチを設け、４ＷＤスイッチによって４輪駆動状態と２輪駆動状態とを切り替える駆動制御構成であっても良い。すなわち、駆動モータ４ＲＬ、４ＲＲの駆動制御は上記制御に限定されない。
【００４４】
また、上記実施形態では、発電機７の発電した電圧で駆動モータ４ＲＬ、４ＲＲを駆動して４輪駆動を構成する場合で説明しているが、これに限定されない。２台の駆動駆動モータ４ＲＬ、４ＲＲヘ電力供給できる共通のバッテリを備えるシステムに採用しても良い。この場合には、バッテリから電力を供給するようにすればよいし、さらにはバッテリからの供給と共に発電機７からの電力供給も併行して行うようにしてもよい。
【００４５】
または、上記実施形態では、主駆動源として内燃機関を例示しているが、主駆動源をモータから構成しても良い。
次に、第２実施形態について図面を参照しつつ説明する。なお、上記実施形態と同様な部分については同一の符号を付して説明する。
本実施形態の基本構成は、上記第１実施形態と同じであるが、モータ制御部８Ｃの処理が異なる。
【００４６】
本実施形態のモータ制御部８Ｃは、図９に示すように、作動判定部５０、目標ヨーレート検出部５１、実ヨーレート検出部５２、上記偏差演算部５３、極性反転部５４、左後輪制御部５５、及び右後輪制御部５６を備える。偏差演算部５３が、駆動力差検出手段を構成し、極性反転部５４、左後輪制御部５５、及び右後輪制御部５６が、界磁電流補正手段を構成する。
【００４７】
作動判定部５０は、２台の駆動モータ４ＲＬ、４ＲＲの界磁電流指令値を補正するか否かを判定する。作動判定部５０は、次の▲１▼〜▲３▼の条件を満足していると判定すると、界磁電流指令値を補正を実施するとして、目標ヨーレート検出部５１、実ヨーレート検出部５２に起動指令を出力する。また、下記の▲１▼〜▲３▼の条件を満足し無くなると、停止指令を出力する。
【００４８】
▲１▼Ｔｈ＞０、つまり、発電機７が発電して４輪駆動状態となっている。
▲２▼ＴＣＳ制御などの強制制動制御が実施されていない。
▲３▼ステアリングホイールの操舵角がゼロ近傍、つまり、操舵角の絶対値が所定角度以内である。所定角度とは、運転者が直進走行を指示しているとされる、ステアリングホイールの操作量の範囲内であることを指す。
【００４９】
次に、目標ヨーレート検出部５１は、起動指令を入力すると作動を開始して、舵角センサからの操舵角検出値を入力すると共に車速センサから車速を入力して、公知の計算によって目標ヨーレートを演算して偏差演算部５３に連続的に出力する。
同様に、実ヨーレート検出部５２は、ヨーレートセンサからの信号に基づき実ヨーレート値を偏差演算部５３に連続的に出力する。
【００５０】
偏差演算部５３は、入力した目標ヨーレートと実ヨーレートとの偏差を演算して、その偏差量に応じた値を、直接に左後輪制御部５５へ出力すると共に、極性反転部５４を介して極性を反転させてから右後輪制御部５６に出力する。
上記偏差演算部５３は、作動増幅部５３Ａ、積分回路５３Ｂ、及びサンプル／ホールド回路５３Ｃから構成される。作動増幅部５３Ａは、目標ヨーレートよりも実ヨーレートが右旋回傾向にある場合を「プラス値」、左旋回傾向にある場合を「マイナス値」として偏差量を求め、続いて積分回路５３Ｂで、例えば時定数１秒程度のフィルタでＡＣ分を除去し、サンプル／ホールド回路５３Ｃで車輪スリップ時及び舵角が所定舵角以上の場合には直前の値を保持する処理を行う。
【００５１】
次に、左後輪制御部５５は、余剰トルク変換部８Ｇが求めた目標駆動モータ界磁電流Ｉｆｍに偏差演算部５３から入力した偏差値を加算した値を左後輪側駆動モータ４ＲＬ、４ＲＲのモータ界磁電流となるように制御する。
また、右後輪制御部５６は、余剰トルク変換部８Ｇが求めた目標駆動モータ界磁電流Ｉｆｍに偏差演算部５３から入力した、極性を反転した偏差値を加算した値を右後輪側駆動モータ４ＲＬ、４ＲＲのモータ界磁電流となるように制御する。
【００５２】
本実施形態の作用効果などについて説明する。
理論的には、第１実施形態で説明したように、直進走行状態では、左右の駆動モータ４ＲＬ、４ＲＲの駆動トルクは等しいはずであるが、機械・磁界効率の違いなどによって、左右の駆動モータ４ＲＬ、４ＲＲの駆動トルクに差が出るおそれがある。これに対して、本実施形態では、目標ヨーレートと実ヨーレートとの偏差から、左右後輪３Ｌ、３Ｒの発生駆動力差に応じた値を演算し、その偏差が小さくなる方向に、左右の駆動モータ４ＲＬ、４ＲＲの界磁電流値をそれぞれ補正しているので、より直進走行時の安定性が向上する。
【００５３】
ここで、界磁電流の補正は、路面摩擦係数の左右アンバランスの影響を受けないように、ＴＣＳ制御などが行われていないグリップ走行時に行っている。さらに、旋回時のヨーレートで偏差を検出しないように舵角がゼロ近傍付近の場合にのみ界磁電流の補正を行うようにしている。
また、界磁電流の変化で２つのモータの端子電圧の和が変化しないように、界磁電流の補正量の絶対値が左右の駆動モータ４ＲＬ、４ＲＲで同じ値となるように修正している。また、左右の界磁電流の補正値は、一方の値の極性を反転しているだけであるので、演算が簡易である。
【００５４】
その他の構成や作用・効果は第１実施形態と同様である。
次に、第３実施形態について図面を参照しつつ説明する。なお、上記各実施形態と同様な部分については同一の符号を付して説明する。
本実施形態の基本構成は、上記第２実施形態と同じであるが、モータ制御部８Ｃの処理の一部が異なる。
【００５５】
本実施形態のモータ制御部８Ｃは、図１０に示すように、作動判定部５０、右輪駆動トルク演算部６１、左輪駆動トルク演算部６２、偏差演算部５３、極性反転部５４、左後輪制御部５５、及び右後輪制御部５６を備える。
右輪駆動トルク演算部６１は、右側の駆動モータ４ＲＬ、４ＲＲに設けたトルクセンサからの信号に基づき右後輪３Ｌ、３Ｒの駆動トルクを演算して作動増幅部５３Ａに出力する。左輪駆動トルク演算部６２は、左側の駆動モータ４ＲＬ、４ＲＲに設けたトルクセンサからの信号に基づき左後輪３Ｌ、３Ｒの駆動トルクを演算して作動増幅部５３Ａに出力する。作動増幅部５３Ａは、右輪駆動トルクが大きいときにプラス値で偏差を出力し、左輪駆動トルクが大きいときにマイナス値で偏差を出力する。
【００５６】
その他のモータ制御部８Ｃの構成は、上記第２実施形態のモータ制御部８Ｃと同じである。
そして、本実施形態では、左右の駆動トルク差から左右輪の発生駆動力の偏差に応じた値を演算し、その偏差が小さくなるように左右の駆動モータ４ＲＬ、４ＲＲの界磁電流値をそれぞれ補正する。
【００５７】
作用・効果などについては上記第２実施形態と同様である。
次に、第４実施形態について図面を参照しつつ説明する。なお、上記各実施形態と同様な部分については同一の符号を付して説明する。
図１１は本実施形態の駆動制御装置の構成図を示す図である。
本実施形態では、図１１に示すように、左右前輪もそれぞれ、第１実施形態で説明した構造の駆動モータ４ＦＬ、４ＦＲで個別に駆動可能となっている。
【００５８】
そして、４輪にそれぞれ対応する４台の駆動モータ４ＲＬ、４ＲＲ、４ＦＬ、４ＦＲに対して、上記発電機７から電力が供給可能となっている。本実施形態では、図１２に示すように、共通の電源である発電機７に対して、４台の駆動モータ４ＲＬ、４ＲＲ、４ＦＬ、４ＦＲは電気的に直列に接続されている。
また、４ＷＤコントローラ８では、アクセル開度に応じて発電機７を発電させると共に、４ＷＤスイッチからの信号に基づき、左右後輪側のクラッチ１２ＲＬ、１２ＲＲの接続・非接続を実行して４輪駆動状態と２輪駆動状態との切替を行う。なお、主駆動輪が前輪の場合で説明しているが、２輪駆動時に駆動される主駆動輪は後輪３Ｌ、３Ｒであっても良いし、前輪後輪切替スイッチなどを設けて、状況に応じて２輪駆動時に駆動される車輪を前輪若しくは後輪３Ｌ、３Ｒに切替可能になっていても良い。
【００５９】
また、上記第２及び第３実施形態で説明した界磁電流値の補正制御を行う場合には、左右で対になる車輪間で界磁電流値の補正を実施するので、左右前輪間でも上記界磁電流値の補正を、左右後輪間の界磁電流値の補正とは別に行う。
また、上記説明では、４台の駆動モータ４ＲＬ、４ＲＲ、４ＦＬ、４ＦＲが全て直列に発電機７に接続されると説明しているが、左右で対をなす車輪の駆動モータ４ＲＬ、４ＲＲ間が電気的に直列に接続されていればよい。すなわち、図１３に示すように、左右前輪に対応した２個の駆動モータ４ＲＬ、４ＲＲを直列に接続すると共に、左右後輪３Ｌ、３Ｒに対応した２個の駆動モータ４ＲＬ、４ＲＲを直列に接続するが、発電機７に対して、左右前輪に対応した２個の駆動モータ４ＦＬ、４ＦＲと左右後輪３Ｌ、３Ｒに対応した２個の駆動モータ４ＲＬ、４ＲＲとを並列に接続しても良い。
【００６０】
このように、左右前輪もそれぞれ駆動モータ４ＦＬ、４ＦＲで駆動制御される構成であっても、車両の直進走行における安定性が向上する。
ここで、上記実施形態では、左右後輪側の駆動モータ４ＲＬ、４ＲＲの電源と、左右前輪側の駆動モータ４ＦＬ、４ＦＲの電源とを共通の発電機７としているが、左右後輪側の駆動モータ４ＲＬ、４ＲＲの電源と、左右前輪側の駆動モータ４ＦＬ、４ＦＲの電源とを別に構成しても良い。要は、左右で対向する車輪の組を駆動するモータが、それぞれ共通の電源に対して直列に接続されていればよい。
【００６１】
次に、第５実施形態について図面を参照しつつ説明する。なお、上記各実施形態と同様な部分については同一の符号を付して説明する。
本実施形態の基本構成は、図１４に示すように、上記第４実施形態と同様であるが、共通の電源が、図１５に示すように、発電機７、バッテリ７０、及び電流制御回路７１から構成されている。
本実施形態にあっては、バッテリ７０を備えていても、４台の駆動モータ４ＲＬ、４ＲＲ、４ＦＬ、４ＦＲを直列に接続する結果、電流制御回路７１が１つで済む。
その他の構成や作用・効果については上記第４実施形態と同様である。
【図面の簡単な説明】
【図１】本発明に基づく第１実施形態に係る概略装置構成図である。
【図２】本発明に基づく第１実施形態に係るモータと車輪との接続を示す構成図である。
【図３】本発明に基づく第１実施形態に係る発電機と各モータとの接続状態を示す図である。
【図４】本発明に基づく第１実施形態に係る４ＷＤコントローラを示すブロック図である。
【図５】本発明に基づく第１実施形態に係る余剰トルク演算部の処理を示す図である。
【図６】本発明に基づく第１実施形態に係る目標トルク制御部の処理を示す図である。
【図７】本発明に基づく第１実施形態に係る余剰トルク変換部の処理を示す図である。
【図８】本発明に基づく実施形態に係るエンジンコントローラの処理を示す図である。
【図９】本発明に基づく第２実施形態に係るモータ制御部を示すブロック図である。
【図１０】本発明に基づく第３実施形態に係るモータ制御部を示すブロック図である。
【図１１】本発明に基づく第４実施形態に係る概略装置構成図である。
【図１２】本発明に基づく第４実施形態に係るモータと車輪との接続を示す構成図である。
【図１３】本発明に基づく第４実施形態に係る別の概略装置構成図である。
【図１４】本発明に基づく第５実施形態に係る概略装置構成図である。
【図１５】本発明に基づく第５実施形態に係るモータと車輪との接続を示す構成図である。
【符号の説明】
１Ｌ、１Ｒ 前輪
２ エンジン
３Ｌ、３Ｒ 後輪
４ＲＬ、４ＲＲ、４ＦＬ、４ＦＲ
駆動モータ
６ ベルト
７ 発電機
８ ４ＷＤコントローラ
８Ａ 発電機制御部
８Ｂ リレー制御部
８Ｃ モータ制御部
８Ｄ クラッチ制御部
８Ｅ 余剰トルク演算部
８Ｆ 目標トルク制限部
８Ｇ 余剰トルク変換部
９ 電線
１０ ジャンクションボックス
１１ＲＬ、１１ＲＲ 減速機
１２ＲＬ、１２ＲＲ クラッチ
１４ 吸気管路
１５ メインスロットルバルブ
１６ サブスロットルバルブ
１８ エンジンコントローラ
１９ ステップモータ
２０ 駆動モータコントローラ
２１ エンジン回転数センサ
２２ 電圧調整器
２３ 電流センサ
２６ 駆動モータ用回転数センサ
２７ＦＬ、２７ＦＲ、２７ＲＬ、２７ＲＲ
車輪速センサ
３０ トランスミッション
３１ ディファレンシャル・ギヤ
３２ シフト位置検出手段
３４ ブレーキペダル
３５ ブレーキストロークセンサ
３６ 制動コントローラ
３７ＦＬ、３７ＦＲ、３７ＲＬ、３７ＲＲ
制動装置
４０ アクセルセンサ
５０ 作動判定部
５１ 目標ヨーレート検出部
５２ 実ヨーレート検出部
５３ 偏差演算部
５３Ａ 作動増幅部
５３Ｂ 積分回路
５３Ｃ サンプル／ホールド回路
５４ 極性反転部
５５ 左後輪制御部
５６ 右後輪制御部
６１ 右輪駆動トルク演算部
６２ 左輪駆動トルク演算部
７０ バッテリ
７１ 電流制御回路
Ｉｆｈ 発電機の界磁電流
Ｖ 発電機の電圧
Ｎｈ 発電機の回転数
Ｉａ 目標電機子電流
Ｉｆｍ 目標駆動モータ界磁電流
Ｅ 駆動モータの誘起電圧
Ｎｍ 駆動モータの回転数（回転速度）
ΔＮｍ 駆動モータの回転加速度
ＴＧ 発電機負荷トルク
Ｔｈ 目標発電機負荷トルク
Ｔｅ エンジンの出力トルク[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drive control device for a vehicle that drives all or a part of wheels by a motor.
[0002]
[Prior art]
2. Description of the Related Art As a conventional drive control device that drives a part of a plurality of wheels by a motor, for example, there is a drive control device described in Patent Document 1.
In this drive control device, the left and right front wheels are driven by an engine, and the left and right rear wheels are driven by individual motors. Two motors for driving the left and right rear wheels, respectively, are arranged at the center of the vehicle width direction on the rear side of the vehicle, and each motor is connected to the corresponding wheel via a respective speed reducer.
[0003]
The two motors are supplied with power from a second generator, which is a power source, and the field current is controlled by an electronic control unit to control the electromotive force, and further the generated driving force at each connected wheel. I do. In the related art, a power supply including the second generator and the two motors are electrically connected in parallel.
[0004]
[Patent Document 1]
JP 2000-318473 A
[Problems to be solved by the invention]
When the motors for individually driving the left and right wheels are arranged at the center in the vehicle width direction as described above, the rear floor height increases accordingly.
In addition, since two motors are connected in parallel to the power supply, the armature current values of the two motors differ due to variations in the DC resistance and back electromotive force of the motors. There may be a difference in force. The difference between the left and right driving forces affects the stability during straight running.
[0006]
The present invention has been made in view of the above-mentioned problems, and improves the stability in straight running by simple means even in a vehicle in which the left and right wheels are individually driven by respective drive motors. The task is to be able to do it.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention provides a vehicle including at least one pair of left and right wheels, a plurality of motors that individually drive at least each of the one pair of left and right wheels. A power supply for supplying power to the plurality of motors,
A plurality of motors respectively driving left and right pairs of wheels are electrically connected in series to the power supply.
The "pair of left and right wheels" is a pair of left and right front wheels and another pair of left and right rear wheels in a vehicle including four left and right front wheels and right and left rear wheels.
[0008]
【The invention's effect】
According to the present invention, since the motors of the left and right wheels are connected in series to the common power supply, the armature current values to the respective motors become equal, so that the generated driving forces of the left and right wheels are adjusted to the same value. It will be easier.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a system configuration of a vehicle according to the present embodiment.
As shown in FIG. 1, in the vehicle of the present embodiment, left and right front wheels 1L, 1R are driven by an engine 2, which is an internal combustion engine, and left and right rear wheels 3L, 3R are individually driven by drive motors 4RL, 4RR. Can be driven. That is, the left and right rear wheels 3L, 3R are driven by individual drive motors 4RL, 4RR, respectively.
[0010]
In the present embodiment, as shown in FIG. 2, the drive shafts of the drive motors 4RL and 4RR are directly connected to the axles of the corresponding rear wheels 3L and 3R via the speed reducers 11RL and 11RR and the clutches 12RL and 12RR. It is connected.
The output torque Te of the engine 2 is transmitted to the left and right front wheels 1L and 1R through the transmission 30 and the difference gear 31.
[0011]
The transmission 30 is provided with a shift position detecting means 32 for detecting a current shift range. The shift position detecting means 32 outputs a detected shift position signal to the 4WD controller 8.
A main throttle valve 15 and a sub-throttle valve 16 are interposed in an intake pipe 14 (for example, an intake manifold) of the engine 2. The throttle opening of the main throttle valve 15 is adjusted and controlled according to the amount of depression of an accelerator pedal 17 which is an accelerator opening instruction device (acceleration instruction operation unit). The engine controller 18 electrically controls the main throttle valve 15 in response to the depression amount of the accelerator pedal 17 mechanically or in accordance with a depression amount detection value of an accelerator sensor 40 for detecting the depression amount of the accelerator pedal 17. , The throttle opening is adjusted. The depression amount detection value of the accelerator sensor 40 is also output to the 4WD controller 8.
[0012]
The opening of the sub-throttle valve 16 is adjusted and controlled by a rotation angle corresponding to the number of steps, using a step motor 19 as an actuator. The rotation angle of the step motor 19 is adjusted and controlled by a drive signal from a drive motor controller 20. The sub-throttle valve 16 is provided with a throttle sensor, and the number of steps of the step motor 19 is feedback-controlled based on a throttle opening detection value detected by the throttle sensor. Here, the output torque of the engine 2 is controlled independently of the operation of the accelerator pedal by the driver by adjusting the throttle opening of the sub-throttle valve 16 to the opening of the main throttle valve 15 or less. Can be.
[0013]
The engine rotation speed sensor 21 detects the rotation speed of the engine 2, and outputs the detected signal to the engine controller 18 and the 4WD controller 8.
Reference numeral 34 denotes a brake pedal which constitutes a braking instruction operation unit. The stroke amount of the brake pedal 34 is detected by a brake stroke sensor 35. The brake stroke sensor 35 outputs the detected brake stroke amount to the brake controller 36 and the 4WD controller 8.
[0014]
The braking controller 36 controls the braking force acting on the vehicle through braking devices 37FL, 37FR, 37RL, 37RR such as disk brakes mounted on each of the wheels 1L, 2R, 3L, 3R according to the input brake stroke amount. .
In addition, a part of the rotational torque Te of the engine 2 is transmitted to the generator 7 via the endless belt 6, and the generator 7 rotates the rotational speed Ne of the engine 2 by a pulley ratio. Rotate at Nh.
[0015]
The generator 7 includes a voltage regulator 22 (regulator) for adjusting the output voltage V. The generator control command value c1 (duty ratio) is controlled by the 4WD controller 8, so that the generator 7 controls the field current Ifh. The power generation load torque Th for the engine 2 and the voltage V for power generation are controlled. That is, the voltage regulator 22 receives the generator control command c1 (field current value) from the 4WD controller 8, adjusts the field current Ifh of the generator 7 to a value corresponding to the generator control command c1, and , The output voltage V of the generator 7 can be detected and output to the 4WD controller 8. The rotation speed Nh of the generator 7 can be calculated from the rotation speed Ne of the engine 2 based on the pulley ratio.
[0016]
The power generated by the generator 7 can be supplied to the two drive motors 4RL and 4RR via the electric wire 9. The generator 7 and the two drive motors 4RL and 4RR are electrically connected in series as shown in FIG.
A junction box 10 is provided in the middle of the electric wire 9. A current sensor 23 is provided in the junction box 10, and the current sensor 23 detects a current value Ia of electric power supplied from the generator 7 to the two drive motors 4RL and 4RR, and detects the detected armature current. The signal is output to the 4WD controller 8. Further, a voltage value (voltage of the drive motors 4RL, 4RR) flowing through the electric wire 9 is detected by the 4WD controller 8. Reference numeral 24 denotes a relay, which controls interruption and connection of a voltage (current) supplied to the drive motors 4RL and 4RR in accordance with a command from the 4WD controller 8.
[0017]
The field currents of the two drive motors 4RL and 4RR are individually controlled by a command from the 4WD controller 8, and the drive torque to the connected rear wheels 3L and 3R is adjusted by adjusting the field current. Is done.
A drive motor rotation speed sensor 26 for detecting the rotation speed Nm of the drive shaft of each of the drive motors 4RL and 4RR is provided. The drive motor rotation sensor 26 outputs a detected rotation speed signal of the drive motors 4RL and 4RR to 4WD. Output to the controller 8. The drive motor rotational speed sensor 26 constitutes an input shaft side rotational speed detecting means.
[0018]
Each of the clutches 12 is a hydraulic clutch or an electromagnetic clutch, and is brought into a connected state or a disconnected state in response to a clutch control command from the 4WD controller 8.
Further, wheel speed sensors 27FL, 27FR, 27RL, 27RR are provided for the respective wheels 1L, 1R, 3L, 3R. Each wheel speed sensor 27FL, 27FR, 27RL, 27RR outputs a pulse signal corresponding to the rotation speed of the corresponding wheel 1L, 1R, 3L, 3R to the 4WD controller 8 as a wheel speed detection value.
[0019]
As shown in FIG. 4, the 4WD controller 8 includes a generator control unit 8A, a relay control unit 8B, a motor control unit 8C, a clutch control unit 8D, a surplus torque calculation unit 8E, a target torque limit unit 8F, and a surplus torque conversion unit. 8G.
The generator control unit 8A adjusts the field current Ifh by outputting the generator command value c1 of the generator 7 while monitoring the generated voltage V of the generator 7 through the voltage regulator 22.
[0020]
The relay control unit 8B controls disconnection and connection of power supply from the generator 7 to the drive motors 4RL and 4RR.
The clutch control unit 8D controls the state of the clutches 12RL, 12RR by outputting a clutch control command to the clutches 12RL, 12RR.
Further, at every predetermined sampling time, based on the input signals, the processing is performed in the order of the surplus torque calculating section 8E → the target torque limiting section 8F → the surplus torque converting section 8G.
[0021]
Next, the surplus torque calculation unit 8E performs a process as shown in FIG.
That is, first, in step S10, the rear wheels 3L, 3R (slave drive wheels) are calculated from the wheel speeds of the front wheels 1L, 1R (main drive wheels) calculated based on the signals from the wheel speed sensors 27FL, 27FR, 27RL, 27RR. By subtracting the wheel speed, a slip speed ΔVF, which is an acceleration slip amount of the front wheels 1L and 1R, is obtained, and the process proceeds to step S20.
[0022]
Here, the calculation of the slip speed ΔVF is performed, for example, as follows.
The average front wheel speed VWf, which is the average value of the left and right wheel speeds at the front wheels 1L, 1R, and the average rear wheel speed VWr, which is the average value of the left and right wheel speeds at the rear wheels 3L, 3R, are calculated by the following equations.
VWf = (VWfl + VWfr) / 2
VWr = (VWrl + VWrr) / 2
Next, from the deviation between the average front wheel speed VWf and the average rear wheel speed VWr, the slip speed (acceleration slip amount) ΔVF of the front wheels 1L, 1R, which are the main drive wheels, is calculated by the following equation.
ΔVF = VWf−VWr
[0023]
In step S20, it is determined whether the obtained slip speed ΔVF is larger than a predetermined value, for example, zero. If the slip speed ΔVF is determined to be 0 or less, it is estimated that the front wheels 1L and 1R are not accelerating and slipping. Therefore, the process proceeds to step S30, and the process returns after substituting zero for Th.
[0024]
On the other hand, if it is determined in step S20 that the slip speed ΔVF is greater than 0, it is estimated that the front wheels 1L and 1R are accelerating and the process proceeds to step S40.
In step S40, the absorption torque TΔVF required to suppress the acceleration slip of the front wheels 1L, 1R is calculated by the following equation, and the process proceeds to step S50. This absorption torque TΔVF is an amount proportional to the acceleration slip amount.
[0025]
TΔVF = K1 × ΔVF
Here, K1 is a gain obtained by an experiment or the like.
In step S50, the current load torque TG of the generator 7 is calculated based on the following equation, and then the process proceeds to step S60.

here,
V: voltage Ia of the generator 7: armature current Nh of the generator 7: rotation speed K3 of the generator 7: efficiency K2: coefficient.
In step S60, a surplus torque, that is, a target power generation load torque Th to be loaded by the generator 7 is determined based on the following equation, and the process returns.
[0026]
Th = TG + TΔVF
Next, the processing of the target torque limiting unit 8F will be described with reference to FIG.
That is, first, in step S110, it is determined whether the target power generation load torque Th is greater than the maximum load capacity HQ of the generator 7. When it is determined that the target power generation load torque Th is equal to or less than the maximum load capacity HQ of the generator 7, the process returns. On the other hand, when it is determined that the target power generation load torque Th is larger than the maximum load capacity HQ of the generator 7, the process proceeds to step S120.
[0027]
In step S120, the excess torque ΔTb exceeding the maximum load capacity HQ at the target power generation load torque Th is obtained by the following equation, and the process proceeds to step S130.
ΔTb = Th−HQ
In step S130, the current engine torque Te is calculated based on the signals from the engine speed detection sensor 21 and the throttle sensor and the like, and the process proceeds to step S140.
[0028]
In step S140, the engine torque upper limit TeM is calculated by subtracting the excess torque ΔTb from the engine torque Te, and the calculated engine torque upper limit TeM is output to the engine controller 18 as in the following equation. Transition.
TeM = Te−ΔTb
In step S150, the process returns after substituting the maximum load capacity HQ for the target power generation load torque Th.
[0029]
Next, the processing of the surplus torque converter 8G will be described with reference to FIG.
Note that all or a part of the processing of the surplus torque conversion unit 8G may be performed individually for each drive motor.
First, in step S200, it is determined whether Th is greater than 0. If it is determined that Th> 0, it means that the front wheels 1L and 1R are performing an acceleration slip, and the process proceeds to step S220. If it is determined that Th ≦ 0, the front wheels 1L, 1R are in a state in which no acceleration slip has occurred, and thus return to the original state.
[0030]
Next, in step S220, the rotation speed Nm of the drive motors 4RL and 4RR detected by the drive motor rotation speed sensor 21 is input, and the target drive motor field current Ifm corresponding to the rotation speed Nm of the drive motors 4RL and 4RR. Is calculated and the target drive motor field current Ifm is output to the electric motor control unit 8C, and then the flow shifts to step S230.
[0031]
Here, the target drive motor field current Ifm with respect to the rotation speed Nm of the drive motors 4RL and 4RR is a constant predetermined current value when the rotation speed Nm is equal to or lower than the predetermined rotation speed. When the number of rotations becomes equal to or more than the rotation speed, the field current Ifm of the drive motors 4RL and 4RR is reduced by a known field weakening control method. That is, when the drive motors 4RL and 4RR rotate at a high speed, the drive motor torque decreases due to the increase in the induced voltage E of the drive motors 4RL and 4RR. As described above, the rotation speed Nm of the drive motors 4RL and 4RR is set to the predetermined value. When the above occurs, the field current Ifm of the drive motors 4RL and 4RR is reduced to reduce the induced voltage E, thereby increasing the current flowing through the drive motors 4RL and 4RR to obtain the required drive motor torque. As a result, even if the drive motors 4RL, 4RR rotate at a high speed, a rise in the induced voltage E of the drive motors 4RL, 4RR is suppressed and a decrease in the drive motor torque is suppressed, so that a required drive motor torque can be obtained. In addition, by controlling the drive motor field current Ifm in two stages of less than a predetermined number of revolutions and more than a predetermined number of revolutions, an electronic circuit for control can be reduced in cost as compared with continuous field current control.
[0032]
Note that a drive motor torque correction unit that continuously corrects the drive motor torque by adjusting the field current Ifm according to the rotation speed Nm of the drive motors 4RL and 4RR for the required drive motor torque may be provided. That is, it is preferable to adjust the field current Ifm of the drive motors 4RL and 4RR in accordance with the rotational speed Nm of the drive motors 4RL and 4RR for the two-stage switching. As a result, even if the drive motors 4RL and 4RR rotate at a high speed, a rise in the induced voltage E of the drive motors 4RL and 4RR is suppressed and a decrease in the drive motor torque is suppressed, so that a required drive motor torque can be obtained. Further, since the drive motor torque characteristics can be made smooth, the vehicle can run more stably as compared with the two-stage control, and the drive efficiency of the drive motors 4RL and 4RR can always be in a good state.
[0033]
Next, in step S230, the corresponding target drive motor torque Tm (n) is calculated from a map or the like based on the power generation load torque Th calculated by the surplus torque calculation unit 8E, and the process proceeds to step S240.
In step S240, using the target drive motor torque Tm (n) and the target drive motor field current Ifm as variables, a corresponding target armature current Ia is determined based on a map or the like, and the process proceeds to step S310.
[0034]
In step S310, the duty ratio c1, which is a generator control command value, is calculated and output based on the target armature current Ia, and then the process returns.
Next, processing of the motor control unit 8C will be described. The motor control unit 8C adjusts the field currents of the two drive motors 4RL and 4RR so that the target drive motor field current Ifm obtained by the surplus torque conversion unit 8G is obtained. Adjust the 4RR torque to the required value.
[0035]
Next, the processing of the engine controller 18 will be described.
In the engine controller 18, a process as shown in FIG. 8 is performed based on each input signal at every predetermined sampling time.
That is, first, in step S610, the target output torque TeN required by the driver is calculated based on the detection signal from the accelerator sensor 40, and the process proceeds to step S620.
[0036]
In step S620, it is determined whether there is an input of the limited output torque TeM from the 4WD controller 8. If it is determined that there is an input, the process moves to step S630. On the other hand, when it is determined that there is no input, the process proceeds to step S670.
In step S630, it is determined whether the target output torque TeN is larger than the limited output torque TeM. When it is determined that the target output torque TeN is larger than the limited output torque TeM, the process proceeds to step S640. On the other hand, if the limit output torque TeM is larger or equal to the target output torque TeN, the process proceeds to step S670.
[0037]
In step S640, the target output torque TeN is reduced by substituting the limit output torque TeM for the target output torque TeN, and the process proceeds to step S670.
In step S670, the current output torque Te is calculated based on the throttle opening, the engine speed, and the like, and the flow shifts to step S680.
In step S680, a deviation ΔTe ′ of the target output torque TeN from the current output torque Te is output based on the following equation, and the flow proceeds to step S690.
[0038]
ΔTe ′ = TeN−Te
In step S690, a change .DELTA..theta. In the throttle opening .theta. According to the difference .DELTA.Te is calculated, an opening signal corresponding to the change .DELTA..theta. In the throttle is output to the step motor 19, and the flow returns.
Next, the operation and the like of the apparatus having the above configuration will be described.
[0039]
If the torque transmitted from the engine 2 to the front wheels 1L, 1R becomes larger than the road surface reaction force limit torque due to a small road surface μ or a large depression amount of the accelerator pedal 17 by the driver, that is, the main drive wheel. When the front wheels 1L and 1R accelerate and slip, the clutches 12RL and 12RR are connected, and the generator 7 generates power with the power generation load torque Th corresponding to the acceleration slip amount, thereby shifting to the four-wheel drive state. Subsequently, the driving torque transmitted to the front wheels 1L and 1R is adjusted so as to approach the road surface reaction force limit torque of the front wheels 1L and 1R, thereby shifting to the two-wheel drive state. As a result, the acceleration slip in the front wheels 1L and 1R, which are the main driving wheels, is suppressed.
[0040]
Moreover, the drive motors 4RL, 4RR are driven by the surplus power generated by the generator 7, and the rear wheels 3L, 3R, which are the sub-drive wheels, are also driven, so that the acceleration of the vehicle is improved.
At this time, since the drive motors 4RL, 4RR are driven with excess torque exceeding the road surface reaction force limit torque of the main drive wheels 1L, 1R, energy efficiency is improved, leading to improvement in fuel efficiency.
[0041]
When the four-wheel drive state is set, the armature current is supplied from the generator 7 which is a common power source to the left and right drive motors 4RL and 4RR, but as shown in FIG. As a result, the left and right drive motors 4RL and 4RR are connected in series, so that the armature currents of the left and right drive motors 4RL and 4RR become the same, and the drive torques of the left and right drive motors 4RL and 4RR become the same value. The driving force generated by the left and right wheels driven by the respective driving motors 4RL, 4RR has the same value. As a result, even in a vehicle in which the left and right rear wheels 3L, 3R are individually driven by motors, the stability of the vehicle when traveling straight ahead is improved.
[0042]
In addition, the left and right drive motors 4RL and 4RR are disposed near the corresponding wheels, that is, the two drive motors 4RL and 4RR are not disposed in the center of the vehicle. It also has the effect of increasing the floor space.
However, as in the conventional example, the left and right drive motors 4RL and 4RR may be arranged at the center in the vehicle width direction.
[0043]
Here, in the above-described embodiment, the configuration is described in which the rear wheels 3L and 3R are driven when the front wheels accelerate and slip, but a system that shifts to the four-wheel drive state according to the accelerator opening and the like may be used. Applicable. Alternatively, a drive control configuration may be provided in which a 4WD switch is provided and the 4WD switch switches between the four-wheel drive state and the two-wheel drive state. That is, the drive control of the drive motors 4RL and 4RR is not limited to the above control.
[0044]
Further, in the above-described embodiment, the case where the drive motors 4RL and 4RR are driven by the voltage generated by the generator 7 to form the four-wheel drive has been described, but the present invention is not limited to this. The present invention may be applied to a system including a common battery that can supply power to the two drive motors 4RL and 4RR. In this case, the electric power may be supplied from the battery, or the electric power may be supplied from the generator 7 together with the supply from the battery.
[0045]
Alternatively, in the above embodiment, an internal combustion engine is exemplified as the main drive source, but the main drive source may be configured by a motor.
Next, a second embodiment will be described with reference to the drawings. The same parts as those in the above embodiment will be described with the same reference numerals.
The basic configuration of the present embodiment is the same as that of the first embodiment, except for the processing of the motor control unit 8C.
[0046]
As shown in FIG. 9, the motor control unit 8C of the present embodiment includes an operation determination unit 50, a target yaw rate detection unit 51, an actual yaw rate detection unit 52, the above-described deviation calculation unit 53, a polarity reversal unit 54, and a left rear wheel control unit. 55 and a right rear wheel control unit 56. The deviation calculation unit 53 constitutes a driving force difference detection unit, and the polarity reversing unit 54, the left rear wheel control unit 55, and the right rear wheel control unit 56 constitute a field current correction unit.
[0047]
The operation determining unit 50 determines whether to correct the field current command values of the two drive motors 4RL and 4RR. If the operation determining unit 50 determines that the following conditions (1) to (3) are satisfied, the operation determining unit 50 determines that the field current command value is to be corrected, and the target yaw rate detecting unit 51 and the actual yaw rate detecting unit 52 Outputs start command. When the following conditions (1) to (3) are not satisfied, a stop command is output.
[0048]
{Circle around (1)} Th> 0, that is, the generator 7 generates power and is in a four-wheel drive state.
(2) Forced braking control such as TCS control is not performed.
(3) The steering angle of the steering wheel is close to zero, that is, the absolute value of the steering angle is within a predetermined angle. The predetermined angle indicates that the angle is within the range of the operation amount of the steering wheel, which is assumed to indicate that the driver is instructing straight running.
[0049]
Next, the target yaw rate detection unit 51 starts operating when a start command is input, inputs a steering angle detection value from a steering angle sensor and a vehicle speed from a vehicle speed sensor, and calculates a target yaw rate by a known calculation. The calculated value is continuously output to the deviation calculator 53.
Similarly, the actual yaw rate detector 52 continuously outputs the actual yaw rate value to the deviation calculator 53 based on the signal from the yaw rate sensor.
[0050]
The deviation calculating unit 53 calculates the deviation between the input target yaw rate and the actual yaw rate, outputs a value corresponding to the deviation directly to the left rear wheel control unit 55, and outputs the value via the polarity reversing unit 54. The polarity is inverted and then output to the right rear wheel control unit 56.
The deviation calculator 53 includes an operation amplifier 53A, an integration circuit 53B, and a sample / hold circuit 53C. The operation amplifying unit 53A calculates the deviation amount as a “plus value” when the actual yaw rate is more rightward than the target yaw rate, and a “minus value” when the actual yaw rate is more likely to turn left. Then, the integration circuit 53B calculates For example, the AC component is removed by a filter having a time constant of about 1 second, and the sample / hold circuit 53C performs processing for retaining the immediately preceding value when the wheel slips and when the steering angle is equal to or larger than the predetermined steering angle.
[0051]
Next, the left rear wheel control unit 55 adds a value obtained by adding the deviation value input from the deviation calculation unit 53 to the target drive motor field current Ifm obtained by the surplus torque conversion unit 8G to the left rear wheel side drive motors 4RL, 4RR. Is controlled so as to be the motor field current.
Further, the right rear wheel control unit 56 calculates a value obtained by adding the deviation value inverted in polarity input from the deviation calculation unit 53 to the target drive motor field current Ifm obtained by the surplus torque conversion unit 8G, to the right rear wheel drive. Control is performed so as to be the motor field current of the motors 4RL and 4RR.
[0052]
The operation and effect of the present embodiment will be described.
In theory, as described in the first embodiment, in the straight running state, the driving torques of the left and right driving motors 4RL and 4RR should be equal. There is a possibility that there is a difference between the driving torques of 4RL and 4RR. On the other hand, in the present embodiment, a value corresponding to the generated driving force difference between the left and right rear wheels 3L, 3R is calculated from the deviation between the target yaw rate and the actual yaw rate, and the left and right driving directions are reduced in a direction in which the deviation is reduced. Since the field current values of the motors 4RL and 4RR are respectively corrected, the stability during straight running is further improved.
[0053]
Here, the correction of the field current is performed at the time of grip traveling in which TCS control or the like is not performed so as not to be affected by the right and left imbalance of the road surface friction coefficient. Further, the field current is corrected only when the steering angle is near zero so that the deviation is not detected at the yaw rate at the time of turning.
Further, the absolute value of the correction amount of the field current is corrected so that the left and right drive motors 4RL and 4RR have the same value so that the sum of the terminal voltages of the two motors does not change due to the change in the field current. . In addition, since the correction values of the left and right field currents are only the inversion of the polarity of one value, the calculation is simple.
[0054]
Other configurations, operations, and effects are the same as those of the first embodiment.
Next, a third embodiment will be described with reference to the drawings. The same parts as those in the above embodiments will be described with the same reference numerals.
The basic configuration of the present embodiment is the same as that of the above-described second embodiment, but differs in part of the processing of the motor control unit 8C.
[0055]
As shown in FIG. 10, the motor control unit 8C of the present embodiment includes an operation determination unit 50, a right wheel drive torque calculation unit 61, a left wheel drive torque calculation unit 62, a deviation calculation unit 53, a polarity reversal unit 54, and a left rear wheel. A control unit 55 and a right rear wheel control unit 56 are provided.
The right wheel drive torque calculator 61 calculates the drive torque of the right rear wheels 3L, 3R based on the signals from the torque sensors provided on the right drive motors 4RL, 4RR and outputs the same to the operation amplifier 53A. The left wheel drive torque calculation unit 62 calculates the drive torque of the left rear wheels 3L, 3R based on the signals from the torque sensors provided on the left drive motors 4RL, 4RR and outputs the same to the operation amplifier 53A. The operation amplification unit 53A outputs a deviation with a positive value when the right wheel drive torque is large, and outputs a deviation with a negative value when the left wheel drive torque is large.
[0056]
The other configuration of the motor control unit 8C is the same as the motor control unit 8C of the second embodiment.
In the present embodiment, a value corresponding to the deviation of the driving force generated between the left and right wheels is calculated from the difference between the left and right driving torques, and the field current values of the left and right driving motors 4RL and 4RR are respectively reduced so as to reduce the deviation. to correct.
[0057]
The operation and effect are the same as those in the second embodiment.
Next, a fourth embodiment will be described with reference to the drawings. The same parts as those in the above embodiments will be described with the same reference numerals.
FIG. 11 is a diagram showing a configuration diagram of the drive control device of the present embodiment.
In the present embodiment, as shown in FIG. 11, the left and right front wheels can be individually driven by the drive motors 4FL and 4FR having the structure described in the first embodiment.
[0058]
Then, power can be supplied from the generator 7 to the four drive motors 4RL, 4RR, 4FL, 4FR corresponding to the four wheels, respectively. In the present embodiment, as shown in FIG. 12, four drive motors 4RL, 4RR, 4FL, 4FR are electrically connected in series to a generator 7, which is a common power supply.
In addition, the 4WD controller 8 causes the generator 7 to generate electric power in accordance with the accelerator opening and, based on a signal from the 4WD switch, executes connection / disconnection of the left and right rear wheel side clutches 12RL and 12RR to perform four-wheel drive. The state and the two-wheel drive state are switched. Although the case where the main drive wheel is the front wheel has been described, the main drive wheel driven at the time of two-wheel drive may be the rear wheel 3L, 3R, or may be provided with a front-wheel / rear-wheel changeover switch and the like. May be switched to the front wheels or the rear wheels 3L, 3R in accordance with the above.
[0059]
In the case where the correction control of the field current value described in the second and third embodiments is performed, the correction of the field current value is performed between the paired wheels on the left and right. The correction of the field current value is performed separately from the correction of the field current value between the left and right rear wheels.
In the above description, the four drive motors 4RL, 4RR, 4FL, and 4FR are all connected in series to the generator 7. However, the drive motors 4RL and 4RR of the paired wheels on the left and right are connected. What is necessary is just to be electrically connected in series. That is, as shown in FIG. 13, two drive motors 4RL and 4RR corresponding to the left and right front wheels are connected in series, and two drive motors 4RL and 4RR corresponding to the left and right rear wheels 3L and 3R are connected in series. However, two drive motors 4FL, 4FR corresponding to the left and right front wheels and two drive motors 4RL, 4RR corresponding to the left and right rear wheels 3L, 3R may be connected to the generator 7 in parallel. .
[0060]
In this way, even when the left and right front wheels are also driven and controlled by the drive motors 4FL and 4FR, the stability of the vehicle when traveling straight ahead is improved.
Here, in the above-described embodiment, the power sources of the drive motors 4RL and 4RR on the left and right rear wheels and the power sources of the drive motors 4FL and 4FR on the left and right front wheels are used as the common generator 7. The power supplies for the motors 4RL and 4RR and the power supplies for the drive motors 4FL and 4FR on the left and right front wheels may be configured separately. In short, it is only necessary that the motors that drive the pair of wheels facing each other be connected in series to a common power supply.
[0061]
Next, a fifth embodiment will be described with reference to the drawings. The same parts as those in the above embodiments will be described with the same reference numerals.
The basic configuration of this embodiment is the same as that of the fourth embodiment, as shown in FIG. 14, but the common power source is a generator 7, a battery 70, and a current control circuit 71, as shown in FIG. It is composed of
In the present embodiment, even if the battery 70 is provided, as a result of connecting the four drive motors 4RL, 4RR, 4FL, and 4FR in series, only one current control circuit 71 is required.
Other configurations, operations, and effects are the same as those in the fourth embodiment.
[Brief description of the drawings]
FIG. 1 is a schematic device configuration diagram according to a first embodiment based on the present invention.
FIG. 2 is a configuration diagram showing a connection between a motor and wheels according to the first embodiment of the present invention.
FIG. 3 is a diagram showing a connection state between a generator and each motor according to the first embodiment based on the present invention.
FIG. 4 is a block diagram illustrating a 4WD controller according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a process of a surplus torque calculation unit according to the first embodiment based on the present invention.
FIG. 6 is a diagram illustrating a process of a target torque control unit according to the first embodiment based on the present invention.
FIG. 7 is a diagram showing processing of a surplus torque conversion unit according to the first embodiment based on the present invention.
FIG. 8 is a diagram showing a process of the engine controller according to the embodiment based on the present invention.
FIG. 9 is a block diagram illustrating a motor control unit according to a second embodiment of the present invention.
FIG. 10 is a block diagram showing a motor control unit according to a third embodiment based on the present invention.
FIG. 11 is a schematic device configuration diagram according to a fourth embodiment of the present invention.
FIG. 12 is a configuration diagram showing a connection between a motor and wheels according to a fourth embodiment of the present invention.
FIG. 13 is another schematic device configuration diagram according to a fourth embodiment of the present invention.
FIG. 14 is a schematic device configuration diagram according to a fifth embodiment based on the present invention.
FIG. 15 is a configuration diagram showing a connection between a motor and wheels according to a fifth embodiment based on the present invention.
[Explanation of symbols]
1L, 1R Front wheel 2 Engine 3L, 3R Rear wheel 4RL, 4RR, 4FL, 4FR
Drive motor 6 Belt 7 Generator 8 4WD controller 8A Generator control unit 8B Relay control unit 8C Motor control unit 8D Clutch control unit 8E Excess torque calculation unit 8F Target torque limit unit 8G Excess torque conversion unit 9 Electric wires 10 Junction boxes 11RL, 11RR Reduction gears 12RL, 12RR Clutch 14 Intake line 15 Main throttle valve 16 Subthrottle valve 18 Engine controller 19 Step motor 20 Drive motor controller 21 Engine speed sensor 22 Voltage regulator 23 Current sensor 26 Drive motor speed sensors 27FL, 27FR , 27RL, 27RR
Wheel speed sensor 30 Transmission 31 Differential gear 32 Shift position detecting means 34 Brake pedal 35 Brake stroke sensor 36 Brake controller 37FL, 37FR, 37RL, 37RR
Braking device 40 Accel sensor 50 Operation determination unit 51 Target yaw rate detection unit 52 Actual yaw rate detection unit 53 Deviation calculation unit 53A Operation amplification unit 53B Integration circuit 53C Sample / hold circuit 54 Polarity inversion unit 55 Left rear wheel control unit 56 Right rear wheel control Unit 61 Right wheel drive torque calculation unit 62 Left wheel drive torque calculation unit 70 Battery 71 Current control circuit Ifh Field current of generator V Voltage of generator Nh Number of revolutions of generator Ia Target armature current Ifm Target drive motor field current E Induction voltage Nm of drive motor Number of rotations (rotation speed) of drive motor
ΔNm Rotational acceleration of drive motor TG Generator load torque Th Target generator load torque Te Output torque of engine

Claims (6)

A vehicle including at least one pair of left and right pairs of wheels includes a plurality of motors for individually driving at least each of the one pair of left and right wheels, and a power supply for supplying power to the plurality of motors. ,
A drive control device for a vehicle, wherein a plurality of motors respectively driving left and right pairs of wheels are electrically connected in series to the power supply. The drive control device for a vehicle according to claim 1, wherein in the drive device for a vehicle equipped with an internal combustion engine, the power supply includes a generator driven by the power of the internal combustion engine. Of the wheels driven by the respective motors, the driving force difference detecting means for detecting the driving force difference between the left and right wheels forming a pair on the left and right, and the left and right wheels based on the detection of the driving force difference detecting means 3. The drive control device for a vehicle according to claim 1, further comprising a field current correction unit that corrects a field current value of each motor to be driven. The field current correction means performs the correction when it is determined that the vehicle is traveling straight, and the motors connected to the left and right wheels in a direction in which the driving forces of the left and right wheels become equal based on the detection of the driving force difference detection means. 4. The drive control device for a vehicle according to claim 3, wherein the field current value is corrected. The field current correction means corrects by lowering the field current value of the wheel-side motor having relatively large generated driving force and increasing the field current value of the wheel-side motor having small generated driving force. The vehicle drive control device according to claim 4, wherein: 6. The drive control device for a vehicle according to claim 5, wherein the field current correction unit makes the absolute value of the correction value of the field current of each motor corrected at the same time equal.

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