JP2004034929A - Power transmission and four-wheel-drive car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively constitute a power transmission useful for a driving device having a plurality of shafts, in particular, a four-wheel-drive car and facilitating gear shift control (speed control) of an auxiliary drive shaft comparatively. <P>SOLUTION: Primary current of an induction motor 8 of coil winding type is conducted by electric power outputted from a power generator 6 and fed by a three-phase strong line 12. Frequency f<SB>G</SB>of the primary current can be obtained from the number of revolutions N<SB>e</SB>of an engine because it is proportional to the number of revolutions N<SB>e</SB>of the engine. Consequently, gate control angle β of an inverter can be determined based on the number of revolutions N<SB>vF</SB>of a front wheel 1 and the number of revolutions N<SB>e</SB>of the engine to satisfy expression (V<SB>1</SB>/V<SB>2</SB>)cosβ= (1 -N<SB>VF</SB>P<SB>M</SB>/ aP<SB>G</SB>N<SB>e</SB>b) so that the number of revolutions of the front wheel 1 (main driving shaft 2) and a rear wheel 7 (auxiliary driving shaft 10) agrees actively. P<SB>M</SB>is the number of pairs of pole of the induction motor 8, and P<SB>G</SB>is the number of pairs of pole of the power generator 6. <P>COPYRIGHT: (C)2004,JPO

Description

【数２】
Ｎ_Ｍ＝（１−Ｓ）Ｎ_１　　　　　　　　　　　　　　　　　　　　…（２）
【数３】
Ｓ＝（Ｖ_１／Ｖ_２）ｃｏｓβ　　　　　　　　　　　　　　　　　…（３）
ただし、上記の角度βは、後述のインバータ（図３のＩＮＶ．）のゲート制御角を表すものとする。
【００２４】
したがって、次式（４）が成り立つ様に、誘導モータ８の回転数Ｎ_Ｍを制御すれば、前輪１（主駆動軸２）と後輪７（副駆動軸１０）の回転数Ｎ_ＶＦ，Ｎ_ＶＢを積極的に一致させることができる。
【数４】

【００２５】
言い換えれば、上記の定数ａ，ｂ，Ｐ_Ｇ，Ｐ_Ｍと変数Ｎ_ＶＦ，Ｎ_ｅ等に基づいて、次式（５）が成り立つ様にゲート制御角βを随時決定し、その値に基づいて誘導モータ８の回転数Ｎ_Ｍを制御すれば、前輪１（主駆動軸２）と後輪７（副駆動軸１０）の両回転数を積極的に一致させることができる。
【数５】
（Ｖ_１／Ｖ_２）ｃｏｓβ＝（１−Ｎ_ＶＦＰ_Ｍ／ａＰ_ＧＮ_ｅｂ）　　　…（５）
【００２６】
以下、より具体的な回路に照らして、本実施例を詳細に説明する。
図３は、本第１実施例における、誘導モータ８のロータ回転数の制御方式を例示する回路図であり、本回路は、上記の式（５）を用いて制御される。
ただし、符号Ｌ_ｄは直流リアクトルを表しており、また、本回路において、整流回路（ＲＥＣ．）の直流側電圧Ｅ_ｄは次式（６）を満たし、かつ、インバータ（ＩＮＶ．）の直流側電圧Ｅ_ｉは次式（７）を満たしている。
【数６】
Ｖ_１＝πＥ_ｉ／（３・２^１／２ｃｏｓβ）　　　　　　　　　　　　…（６）
【数７】
Ｖ_２＝πＥ_ｄ／（３・２^１／２Ｓ）　　　　　　　　　　　　　　　…（７）
【００２７】
例えばこの様に、トランジスタＴｒｎ（ｎ＝１，２，．．，６）を有する３相駆動型のインバータ（ＩＮＶ．）を用いて直流側電圧Ｅ_ｉ，Ｅ_ｄを制御することができる。言い換えれば、前記のＥＣＵ１４は、インバータのゲート制御角βを随時制御することにより誘導モータ８の２次電流を制御し、これにより、式（４）が成り立つ様に、誘導モータ８の回転数Ｎ_Ｍを制御するものである。
【００２８】
図４は、上記の回路（図３）を用いて誘導モータ８のロータ回転数を制御する際の制御方式を例示するフローチャートである。即ち、この制御手順は、本発明のロータ回転数可変手段を具現する制御手順を具体的に例示するものである。
本制御手順では、まず最初に、ステップ４１０，４２０において、下記の発電機６の起動条件（発電実行条件）を判定し、これらが共に成立する場合には、ステップ４３０に進む。定数Ｖ０の適当な値としては、例えば１０Ｋｍ／ｈ程度が良い。
【００２９】
＜発電機６の起動条件＞
（ａ）アクセルＯＮ，
かつ、
（ｂ）車速Ｖ≦定数Ｖ０．
或いは、その他にも、前輪と後輪との間における車輪速偏差や、エンジン回転数等を加味しても差し支えない。
また、車両の加速度や、或いは、アクセル・ペダル、ブレーキ・ペダル等の操作量（踏み込み量）等を加味して、発電機６の起動条件を規定しても良い。
【００３０】
ステップ４３０では、発電機６の起動スイッチＧｓｗをＯＮにして、発電機６を起動する。ただし、元来、Ｇｓｗ＝ＯＮだった場合には、本ステップ４３０では何もしなくとも良い。
ステップ４４０では、一次電圧Ｖ_１、エンジン回転数Ｎ_ｅ、及び主駆動軸２の回転数Ｎ_ＶＦの各測定値を入力する。
【００３１】
ステップ４５０では、前述の式（５）を用いて、インバータのゲート制御角βを算出し、更にこの値に基づいて、図３の各トランジスタＴｒｎに対する各出力信号Ｓｎ（ｎ＝１，２，．．，６）の値を決定する。
ステップ４６０では、この出力信号Ｓｎを各トランジスタＴｒｎに対して出力する。
【００３２】
ただし、上記の発電機６の起動条件が成立しなかった場合には、ステップ４７０にて発電機６を停止して（Ｇｓｗ＝ＯＦＦ）、更に、ステップ４８０にて、各出力信号Ｓｎ（ｎ＝１，２，．．，６）の値をすべてＯＦＦにする。尚、元来、Ｇｓｗ＝ＯＦＦである場合には、本ステップ４７０、４８０においては何もしなくとも良い。
【００３３】
ロータ回転数Ｎ_Ｍに関する以上の制御により、誘導モータ８の二次電流が前述の式（４）を満たす様に制御することができる。したがって、例えば以上の様な制御方式に従えば、前輪１（主駆動軸２）と後輪７（副駆動軸１０）の回転数を積極的に一致させることができる。
【００３４】
また、以上の構成によれば、副駆動軸の変速制御（速度制御）が比較的容易な動力伝達装置を、従来より安価に製造することができる。
また、以上の構成に従えば、一般的な車種に対する構造的な差異が比較的小さく、よって、既存の一般車種をも含めて、搭載対象となり得る適用範囲の比較的広い四輪駆動車用の動力伝達装置を、従来より安価に製造することができる。
【００３５】
また、上記の発電機６の起動条件（（ａ）かつ（ｂ））に従えば、車速Ｖの低速領域において、前後輪間の車輪速偏差が生じる前から副駆動軸が駆動されるため、車輪速偏差が生じてから副駆動軸の駆動を開始する従来の動力伝達装置よりも、特に、車両発進時等における走行安定性に優れた装置を提供することができる。
【００３６】
〔第２実施例〕
図５は、本発明の第２実施例に係わる誘導モータ８のロータ回転数の制御方式を例示する回路図である。例えばこの様な昇降圧回路を用いれば、ＦＥＴ（Ｔｒ７，Ｔｒ８）のスイッチング・デューティーを変化させることにより、電圧Ｅ_ｕを自在に制御することができるので、この様な制御方式によっても、ロータ回転数Ｎ_Ｍを所望の値に制御することができる。
また、この方式では、誘導モータの２次側から給電される電力を回生して、図中のバッテリーに蓄電することも可能である。
【００３７】
〔その他の変形例〕
尚、上記の各実施例では、主駆動輪の半径ρ_１と副駆動輪の半径ρ_２とが等しい場合について例示したが、主駆動輪の半径ρ_１と副駆動輪の半径ρ_２とが相異なる場合には、両駆動輪の単位時間当たりの各路面送り長が等しくなる様に制御すれば、主駆動輪のスリップを回避又は緩和することができる。即ち、その様な場合には、次式（８）が成り立つ様に制御すれば良い。
【数８】
２πρ_２ａＮ_Ｍ＝２πρ_１Ｎ_ＶＦ　　　　　　　　　　　　　　　　…（８）
【００３８】
したがって、上記の様な場合には、前述のギヤ比ａの代わりに、次式（９）の定数αを用いれば、上記の実施例と同様の作用・効果を得ることができる。
【数９】
α＝ａ×ρ_２／ρ_１　　　　　　　　　　　　　　　　　　　　　…（９）
【００３９】
また、上記の各実施例では、ＦＦベースの４ＷＤシステムを本発明の動力伝達装置の適用対象システムと仮定し、前輪を主駆動輪としたが、本発明の動力伝達装置の適用対象システムとしては、後輪を主駆動輪とし、前輪を副駆動輪としても良い。即ち、本発明は、ＦＲベースの４ＷＤシステムや、或いはＲＲベースの４ＷＤシステム等にも適用することが可能である。
【００４０】
また、上記の各実施例では、整流器とインバータ、或いは、整流器と昇降圧回路を用いて、誘導モータの速度を制御する方式を例示したが、これらの誘導モータの速度制御には、サイクロコンバータを用いても良い。
【００４１】
また、上記の各実施例では、３相の巻線型の誘導モータを使用した例を示したが、例えば２相の誘導モータ等を使用しても、上記の実施例と略同等の作用・効果を得ることができる。
【図面の簡単な説明】
【図１】本発明の実施例に係わる動力伝達装置を用いた複数軸駆動装置１００のシステム構成図。
【図２】本発明の実施例に係わる動力伝達装置の誘導モータ８の駆動形態を説明する説明図。
【図３】本発明の第１実施例に係わる誘導モータ８のロータ回転数の制御方式を例示する回路図。
【図４】本発明の第１実施例に係わる誘導モータ８のロータ回転数の制御方式を例示するフローチャート。
【図５】本発明の第２実施例に係わる誘導モータ８のロータ回転数の制御方式を例示する回路図。
【図６】従来の動力伝達装置を用いた複数軸駆動装置のシステム構成図。
【符号の説明】
１００　…　複数軸駆動装置
１　…　主駆動輪（前輪）
２　…　主駆動軸
３　…　原動機（エンジン）
４　…　変速機（トランスミッション）
５　…　差動装置（ディファレンシャル・ギヤ）
６　…　発電機
７　…　副駆動輪（後輪）
８　…　誘導モータ
９　…　減速機
１０　…　副駆動軸
１１　…　差動装置（ディファレンシャル・ギヤ）
１２　…　三相強電ライン
１３　…　車輪速センサ
１４　…　ＥＣＵ（電子制御装置）
１６　…　電圧センサ
１９　…　変速機（トランスミッション）
ω　　…　主駆動軸の回転角速度
ｘ　　…　ωの関連値（１例：車輪速Ｎ_ＶＦ）
ａ　　…　減速機９のギヤ比
ｂ　　…　原動機３と発電機６のプーリー比
ｆ_Ｇ　…　発電機６が出力する電力の周波数
Ｐ_Ｇ　…　発電機６の極対数
Ｎ_ｅ　…　原動機３のエンジン回転数〔回転／分〕
Ｎ_ＶＦ　…　車輪速（主駆動輪１の回転数）〔回転／分〕
Ｎ_ＶＢ　…　車輪速（副駆動輪７の回転数）〔回転／分〕
Ｎ_Ｍ　…　誘導モータ８の回転数〔回転／分〕
Ｎ_１　…　誘導モータ８の１次側の回転磁界の回転数〔回転／分〕
Ｐ_Ｍ　…　誘導モータ８の極対数
Ｓ　　…　誘導モータ８のすべり
Ｖ_１　…　誘導モータ８の１次側の電圧（線間電圧実効値）
Ｖ_２　…　誘導モータ８のＮ_Ｍ＝０の時の２次側の誘起電圧（線間電圧実効値）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power transmission device useful for a multi-axis drive device included in a vehicle or the like, and a four-wheel drive vehicle. In particular, miniaturization, weight reduction, cost reduction, and the like are expected in the field of a four-wheel drive vehicle and the like. This is useful for a multi-axis drive device.
[0002]
[Prior art]
As a power transmission device useful for a multi-axis drive device having a main drive shaft and a sub drive shaft, for example, a device described in Japanese Patent Application Laid-Open Publication No. 2000-264086: Four-wheel drive device is generally widely used. Are known.
FIG. 6 is a system configuration diagram illustrating a multi-axis drive device using these conventional power transmission devices.
[0003]
The above power transmission device has the following features.
(1) The motor that drives the sub-drive shaft to rotate is driven by the AC power generated based on the rotational drive force whose rotational speed is proportional to the wheel speed (the rotational speed of the main drive shaft).
(2) The generator is provided between the main drive shaft and a transmission for driving the main drive shaft at a variable speed.
(3) The motor that rotationally drives the sub drive shaft outputs torque when a speed deviation occurs between the rotation speed of the front wheels and the rotation speed of the rear wheels.
[0004]
[Problems to be solved by the invention]
These conventional devices have the following problems.
(Problem 1) Continuously variable transmission and high-speed response When a transmission for rotating the auxiliary drive shaft (rear transmission for rear wheel drive) is used as in the conventional device, mechanical transmission control means is required. Therefore, it is not easy to achieve a continuously variable transmission or a high-speed response with a sufficiently inexpensive rear-wheel drive transmission in the current state of the art.
[0005]
(Problem 2) Installation space In the conventional device, it is necessary to drive the generator with rotation synchronized with the rotation of the main drive wheels. For this reason, it is necessary to attach a generator near the main drive shaft, but it is often not easy to secure such a space near the main drive shaft, and in particular, such as in a four-wheel drive vehicle, etc. The problem has to be noticeable.
[0006]
(Problem 3) Connection interface When a generator is mounted on the main drive shaft, a large change is required in the vicinity of the main drive shaft, particularly in gears for driving the main drive shaft.
[0007]
(Problem 4) Apparatus configuration and control means The conventional apparatus requires the following apparatuses and means for controlling these apparatuses.
(A) Rear-wheel drive power control device (b) Rear-wheel drive transmission device These devices and the control means of these devices are not inexpensive, and therefore, their influence on the entire power transmission device cannot be ignored.
[0008]
(Problem 5) Driving condition of sub-drive shaft The sub-drive shaft is driven to rotate only after a difference in rotational speed (wheel speed deviation) occurs between the main drive shaft and the sub-drive shaft. For this reason, when this conventional power transmission device is applied to, for example, a four-wheel drive vehicle or the like, there occurs a problem that the sub-drive shaft is not driven to rotate unless the main drive shaft slips, and a positive active Slip or the like cannot be avoided beforehand by the operation.
[0009]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power transmission device that is useful for a multi-axis drive device and that can relatively easily control the speed change (speed control) of a sub-drive shaft. That is, the configuration can be made at a lower cost than before.
A further object of the present invention is to provide a four-wheel drive vehicle having a relatively small structural difference with respect to a general vehicle model, and thus having a relatively wide applicable range including a general vehicle model. Is to be configured at a lower cost than before.
[0010]
Means for Solving the Problems, Functions and Effects of the Invention
In order to solve the above-mentioned problems, the following means are effective.
That is, a first means of the present invention is a power transmission device useful for a multi-axis drive device having a main drive shaft and a sub drive shaft, wherein the main transmission device transmits the rotational driving force output by the prime mover to the main drive shaft. A generator driven by the rotational driving force output by the prime mover, an induction motor that is rotationally driven with the alternating current output by the generator as a primary current, and a rotational driving force output by the induction motor to the sub-drive shaft. a secondary transmission device for transmitting, provided with an input interface for inputting a rotation angular velocity ω or a related value x of the main drive shaft, and a rotor rotational speed varying means for varying a rotor rotational speed N _M of the induction motor, the rotor rotational speed by varying means, based on the rotational angular speed ω or related value x, it is to determine the rotor rotational speed N _M.
[0011]
According to the above configuration, the speed control of the sub-drive shaft can be easily performed by the above-described rotor rotation speed varying unit. More specifically, in the speed control of the sub drive shaft according to the above configuration, the shift can be continuously performed with high response by electronic control or the like that executes PWM conversion. Further, since a mechanical multi-stage transmission or a drive power control device for the sub-drive shaft is not required, the device can be configured at a lower cost than before. In addition, such speed control can be easily and simply configured by the above-described electronic control or the like.
In addition, according to the above configuration, a mechanical transmission is not required, so that the device can be configured at a lower cost than before.
[0012]
According to a second aspect of the present invention, in the first aspect, a power regenerating means for regenerating surplus power of the power input to the induction motor is provided.
[0013]
According to such a configuration, the problem of heat generation when the surplus power is consumed by the electric resistance can be avoided, and the power once regenerated in the battery can be reused later for other uses.
[0014]
According to a third aspect of the present invention, in a four-wheel drive vehicle having any one of the power transmission devices described above, a front wheel is driven by a main drive shaft, and a rear wheel is driven by a sub drive shaft. the variable rotational speed means is that each road feeding length per unit time of the front and rear wheels to determine the rotor rotational speed N _M as equal.
[0015]
Here, the road surface feed length per unit time is the distance that the wheel kicks the road surface per unit time, and is represented by 2πρN where ρ is the radius of the wheel and N is the number of revolutions. Therefore, when the wheel radius ([rho) are equal at the front and rear wheels, each rotation speed of the front wheels and the rear wheels may be determined rotor rotational speed N _M as matches.
[0016]
According to such a configuration, the generator can be driven by the rotational driving force synchronized with the engine speed, so that the generator is located at substantially the same position as a normal power generation device provided in a normal vehicle. Can also be arranged. For this reason, the arrangement of the above-mentioned generator becomes easy, and the above-mentioned problem of the installation space and further the problem of the connection interface are solved.
In the above configuration, the front wheel and the rear wheel are interchangeable.
[0017]
That is, a fourth means of the present invention provides a four-wheel drive vehicle having any one of the power transmission devices described above, wherein the front wheels are driven by a sub drive shaft, the rear wheels are driven by a main drive shaft, the variable rotational speed means is that each road feeding length per unit time of the front and rear wheels to determine the rotor rotational speed N _M as equal.
By the means of the present invention described above, the above problems can be effectively or rationally solved.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on specific examples. However, the present invention is not limited to the embodiments described below.
[First embodiment]
FIG. 1 shows a system configuration diagram of a multi-axis drive device 100 using a power transmission device according to the present invention. The object to be driven by the multi-axis drive device 100 is two drive shafts, a main drive shaft 2 and a sub-drive shaft 10, and main drive wheels (front wheels) 1 of a four-wheel drive vehicle are provided at both ends of the main drive shaft 2. Each is fixed. Further, auxiliary drive wheels (rear wheels) 7 of a four-wheel drive vehicle are fixed to both ends of the auxiliary drive shaft 10, respectively.
[0019]
The multi-shaft drive device 100 includes a prime mover (engine) 3 and a power transmission device according to the present invention. In other words, this power transmission device is composed of a part obtained by subtracting the prime mover (engine) 3 from the multi-shaft drive device 100 of FIG. A main transmission device including a device (differential gear) 5; a subtransmission device including a reduction gear 9 and a differential device (differential gear) 11; a generator 6; 8, an input interface unit for inputting a detection signal of the wheel speed sensor 13, an ECU (electronic control unit) 14, a battery 15, a voltage sensor 16, and the like.
[0020]
In the configuration of the power transmission device according to the present invention described above, the control method for driving and controlling the winding type induction motor 8, that is, the speed control method for the auxiliary drive shaft 10 has the following features.
(1) The primary current of the winding-type induction motor 8 is supplied by the power output from the generator 6 and transmitted by the three-phase high-power line 12, and the frequency f _G [Hz] of the primary current is is proportional to the engine speed N _e [rev / min], the frequency f _G (Hz) can be determined from the engine speed N _e.
[0021]
(2) Therefore, the rotation speed N _VF [rotation / minute] of the front wheel 1, that is, the related value N _VF (= 60 × ω / 2π [rotation / minute]) of the rotation angular velocity ω [rad / sec] of the main drive shaft 2 ) And the above-described engine speed _Ne , the rotor speed _NM [rotation / minute] of the induction motor 8 can be appropriately determined. Thereby, the rotation speeds of the front wheel 1 (main drive shaft 2) and the rear wheel 7 (sub drive shaft 10) can be positively matched.
[0022]
Hereinafter, such a speed control method of the sub drive shaft 10 will be described in detail.
FIG. 2 is an explanatory diagram illustrating a driving mode of the induction motor 8 in the power transmission device according to the present invention. The gear ratio of the speed reducer 9 is assumed to be a. Further, the pulley ratio between the prime mover 3 and the generator 6 is represented by b. Hereinafter, the following symbols are used.
(symbol)
_NVB : Rear wheel speed [rev / min]
P _G : Number of pole pairs of generator 6 P _M : Number of pole pairs of induction motor N _M : Number of rotations of induction motor 8 [rotation / minute]
N ₁ ··· The number of rotations of the rotating magnetic field on the primary side of the induction motor 8 [revolutions / minute]
S: slip of the induction motor 8 V ₁ : voltage on the primary side of the induction motor 8 (line voltage effective value)
V ₂ ... Induced voltage on the secondary side when N _M = 0 of the induction motor 8 (line voltage effective value)
[0023]
However, here, the following equation (1) is established from the relationship shown in FIG. 2, and the following equations (2) and (3) are established from the properties of the induction motor 8 and the like.
(Equation 1)

(Equation 2)
N _M = (1-S) N ₁ (2)
[Equation 3]
S = (V ₁ / V ₂ ) cos β (3)
However, the angle β represents a gate control angle of an inverter (INV. In FIG. 3) described later.
[0024]
Therefore, as the following equation (4) holds, by controlling the rotational speed _{N M} of the induction motor 8, the rotational speed _N VF of the front wheels 1 (main drive shaft 2) and the rear wheel 7 (the auxiliary drive shaft 10), N _VB can be positively matched.
(Equation 4)

[0025]
In other words, the above constants _{a, b, P G, P} M and variables _N VF, based on the _{N e,} etc., needed to determine the gate control angle β as the following equation (5) holds, on the basis of the value by controlling the rotational speed N _M of the induction motor 8, it is possible to positively match both rotational speed of the rear wheel 7 (the auxiliary drive shaft 10) the front wheel 1 (main drive shaft 2).
(Equation 5)
_{(V 1 / V 2) cosβ} = (1-N VF P M / aP G N e b) ... (5)
[0026]
Hereinafter, the present embodiment will be described in detail with reference to a more specific circuit.
FIG. 3 is a circuit diagram illustrating a control method of the rotor speed of the induction motor 8 in the first embodiment, and this circuit is controlled using the above equation (5).
However, the code _{L d} denotes a DC reactor, also in this circuit, the DC-side voltage _{E d} of the rectifier circuit (REC.) Satisfies the following equation (6), and the DC side of the inverter (INV.) voltage _{E i} satisfies the following equation (7).
(Equation 6)
^{_{V 1 = πE i / (3}} · 2 1/2 cosβ) ... (6)
(Equation 7)
^{_{V 2 = πE d / (3}} · 2 1/2 S) ... (7)
[0027]
For example Thus, the transistor Trn (n = 1,2, .., 6) can be controlled DC side voltage _E i, the _{E d} with 3-phase drive type inverter (INV.) With. In other words, the ECU 14 controls the secondary current of the induction motor 8 by controlling the gate control angle β of the inverter as needed, whereby the rotation speed N of the induction motor 8 is controlled so that the equation (4) is satisfied. _M is controlled.
[0028]
FIG. 4 is a flowchart illustrating a control method for controlling the rotor speed of the induction motor 8 using the above-described circuit (FIG. 3). That is, this control procedure specifically illustrates a control procedure that embodies the rotor rotation speed varying means of the present invention.
In this control procedure, first, in steps 410 and 420, the following start-up conditions (power generation execution conditions) of the generator 6 are determined, and if both are satisfied, the process proceeds to step 430. An appropriate value of the constant V0 is, for example, about 10 km / h.
[0029]
<Start-up condition of generator 6>
(A) Accelerator ON,
And,
(B) Vehicle speed V ≦ constant V0.
Alternatively, in addition to the above, the wheel speed deviation between the front wheels and the rear wheels, the engine speed, and the like may be added.
In addition, the starting condition of the generator 6 may be defined in consideration of the acceleration of the vehicle, the operation amount (depressed amount) of an accelerator pedal, a brake pedal, and the like.
[0030]
In Step 430, the start switch Gsw of the generator 6 is turned on to start the generator 6. However, if Gsw = ON originally, there is no need to do anything in step 430.
In step 440, the input primary voltage _{V 1,} the engine speed _{N e,} and the measured values of the rotational speed _{N VF} of the main drive shaft 2.
[0031]
In step 450, the gate control angle β of the inverter is calculated using the above equation (5), and based on this value, each output signal Sn (n = 1, 2,...) For each transistor Trn in FIG. , 6) are determined.
In step 460, the output signal Sn is output to each transistor Trn.
[0032]
However, when the above-mentioned starting condition of the generator 6 is not satisfied, the generator 6 is stopped in step 470 (Gsw = OFF), and further, in step 480, each output signal Sn (n = Turn off all the values of 1, 2, ..., 6). When Gsw = OFF, originally, there is no need to do anything in steps 470 and 480.
[0033]
By the above control about the rotor rotational speed N _M, the secondary current of the induction motor 8 can be controlled so as to satisfy the equation (4) above. Therefore, for example, according to the above-described control method, the rotational speeds of the front wheel 1 (main drive shaft 2) and the rear wheel 7 (sub drive shaft 10) can be positively matched.
[0034]
Further, according to the above configuration, it is possible to manufacture a power transmission device in which the speed change control (speed control) of the sub drive shaft is relatively easy at a lower cost than before.
Further, according to the above configuration, the structural difference with respect to a general vehicle model is relatively small, and therefore, for a four-wheel drive vehicle having a relatively wide applicable range that can be mounted, including an existing general vehicle model. The power transmission device can be manufactured at a lower cost than before.
[0035]
Further, according to the above-described starting conditions ((a) and (b)) of the generator 6, in the low-speed region of the vehicle speed V, the sub-drive shaft is driven before a wheel speed deviation occurs between the front and rear wheels. It is possible to provide a device that is more excellent in running stability particularly at the time of starting the vehicle than a conventional power transmission device that starts driving the sub-drive shaft after a wheel speed deviation occurs.
[0036]
[Second embodiment]
FIG. 5 is a circuit diagram illustrating a control method of the rotation speed of the induction motor 8 according to the second embodiment of the present invention. For example, if such a step-up / step-down circuit is used, the voltage _Eu can be freely controlled by changing the switching duty of the FETs (Tr7, Tr8). the number N _M can be controlled to a desired value.
Further, in this system, it is also possible to regenerate the electric power supplied from the secondary side of the induction motor and store it in the battery in the drawing.
[0037]
[Other modifications]
In the above embodiments has been illustrated for the case of the main drive wheel radius [rho ₁ and the radius [rho ₂ of the auxiliary drive wheels is equal, and the radius [rho ₂ of radius [rho ₁ and the auxiliary drive wheel of the main driving wheels In the case where the driving wheels are different from each other, by controlling the road surface feed lengths of both driving wheels per unit time to be equal, the slip of the main driving wheels can be avoided or reduced. That is, in such a case, control may be performed so that the following equation (8) is satisfied.
(Equation 8)
2πρ ₂ aN _M = 2πρ ₁ N _VF (8)
[0038]
Therefore, in the above case, the same operation and effect as in the above embodiment can be obtained by using the constant α in the following equation (9) instead of the gear ratio a.
(Equation 9)
α = a × ρ ₂ / ρ ₁ (9)
[0039]
In each of the above embodiments, the front wheels are used as the main drive wheels, assuming that the FF-based 4WD system is a system to which the power transmission device of the present invention is applied. However, the system to which the power transmission device of the present invention is applied is as follows. Alternatively, the rear wheels may be used as main drive wheels, and the front wheels may be used as auxiliary drive wheels. That is, the present invention can be applied to an FR-based 4WD system, an RR-based 4WD system, and the like.
[0040]
Further, in each of the above embodiments, the method of controlling the speed of the induction motor by using the rectifier and the inverter or the rectifier and the step-up / step-down circuit has been described. May be used.
[0041]
Further, in each of the above-described embodiments, an example in which a three-phase winding type induction motor is used has been described. However, even when a two-phase induction motor or the like is used, for example, the functions and effects substantially the same as those of the above-described embodiment are obtained. Can be obtained.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of a multi-axis drive device 100 using a power transmission device according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram illustrating a driving mode of an induction motor 8 of the power transmission device according to the embodiment of the present invention.
FIG. 3 is a circuit diagram illustrating a control method of a rotor rotation speed of the induction motor 8 according to the first embodiment of the present invention.
FIG. 4 is a flowchart illustrating a method of controlling the number of revolutions of the rotor of the induction motor 8 according to the first embodiment of the present invention.
FIG. 5 is a circuit diagram illustrating a control method of a rotation speed of a rotor of an induction motor 8 according to a second embodiment of the present invention.
FIG. 6 is a system configuration diagram of a multi-axis drive device using a conventional power transmission device.
[Explanation of symbols]
100 Multi-axis drive device 1 Main drive wheel (front wheel)
2… Main drive shaft 3… Motor (engine)
4 ... transmission
5… differential gear (differential gear)
6 ... generator 7 ... auxiliary drive wheel (rear wheel)
8 Induction motor 9 Reducer 10 Sub-drive shaft 11 Differential gear (differential gear)
12 ... three-phase high-power line 13 ... wheel speed sensor 14 ... ECU (electronic control unit)
16: Voltage sensor 19: Transmission
ω: rotational speed of the main drive shaft x: related value of ω (example: wheel speed N _VF )
a: gear ratio of the speed reducer 9 b: pulley ratio f _{G of the} prime mover 3 to the generator 6 frequency of the electric power output by the generator 6 P _G : number of pole pairs N _e of the generator 6 engine rotational speed of the prime mover 3 [ Rotation / min)
N _VF ... wheel speed (number of rotations of main drive wheel 1) [rotation / minute]
_NVB : Wheel speed (number of rotations of auxiliary driving wheel 7) [rotation / minute]
The number of revolutions of the N _M ... induction motor 8 [rev / min]
N ₁ ··· The number of rotations of the rotating magnetic field on the primary side of the induction motor 8 [revolutions / minute]
P _M ... 1 primary voltage of sliding V ₁ ... induction motor 8 of pole pairs S ... induction motor 8 of the induction motor 8 (the line voltage effective value)
V ₂ ... Induced voltage on the secondary side when N _M = 0 of the induction motor 8 (line voltage effective value)

Claims (4)

A power transmission device useful for a multi-axis drive device having a main drive shaft and a sub drive shaft,
A main transmission device for transmitting the rotational driving force output by the prime mover to the main drive shaft,
A generator operated by the rotational driving force output by the motor,
An induction motor that is rotationally driven with the alternating current output by the generator as a primary current,
A sub-transmission device that transmits the rotational driving force output by the induction motor to a sub-drive shaft,
An input interface for inputting a rotational angular velocity ω of the main drive shaft or a related value x thereof,
And a rotor rotational speed varying means for varying a rotor rotational speed N _M of the induction motor,
The rotor rotational speed varying means, on the basis of the rotational angular speed ω or the associated value x, the power transmission device and determines the rotor rotational speed N _M. The power transmission device according to claim 1, further comprising a power regeneration unit that regenerates surplus power of the power input to the induction motor. It has a power transmission device according to claim 1 or claim 2,
Driving the front wheels by the main drive shaft,
The rear wheels are driven by the auxiliary drive shaft,
The rotor rotational speed variation means, the front and the rear as the road surface feeding length per unit time of the wheel is equal, four-wheel drive vehicle and determines the rotor rotational speed N _M. It has a power transmission device according to claim 1 or claim 2,
Driving the front wheels by the auxiliary drive shaft,
Driving the rear wheels by the main drive shaft,
The rotor rotational speed variation means, the front and the rear as the road surface feeding length per unit time of the wheel is equal, four-wheel drive vehicle and determines the rotor rotational speed N _M.

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