JPH06319210A - Vehicle driven by electric motor - Google Patents

Abstract

PURPOSE:To alleviate the shift shock of an automatic speed change gear without the delay in response by the torque control of an electric motor. CONSTITUTION:When the number of revolution of a motor Nm becomes lower than a preset value DELTANm1 nat the up-shift of 1 2, the reaching of inertial phases 2-3 is recognized, and the correcting control is started. Under this state, the torque command value Im is gradually decreased, and the fluctuation part Y of the output torque To caused by the effect of the inertia is absorbed. When the difference between the number of revolutions Nm of the motor and the number of revolutions No of the output becomes the value lower than the preset value DELTANm2, a clutch is completely linked, and the finish 3 of the inertia phase is judged. The torque command value Im is returned to the original value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle having an electric motor and an automatic transmission, for example, an electric motor driven vehicle such as an electric vehicle and a hybrid vehicle, and more particularly to a device for reducing shift shock of the automatic transmission. .

[0002]

2. Description of the Related Art Recently, electric vehicles and hybrid vehicles, which emit no exhaust gas or significantly reduce exhaust gas, have been attracting attention due to increasing environmental problems.

Some vehicles of this type, particularly hybrid vehicles, transmit the rotation from the power source to the wheels via an automatic transmission. The automatic transmission changes the transmission path of a transmission gear mechanism including a planetary gear by engaging or disengaging a friction engagement member such as a clutch or a brake to obtain a desired torque ratio. When engaging or releasing the coupling member, a sudden change occurs in the output torque, which causes a shift shock.

Conventionally, in an automatic transmission, an accumulator, an orifice, etc. are arranged in a control hydraulic circuit for controlling a friction engagement member, and a cushion plate is interposed in the friction engagement member to reduce shift shock. There is.

Further, Japanese Patent Laid-Open No. 63-203430 discloses a hybrid drive vehicle in which front wheels are driven by an engine via an automatic transmission and rear wheels are driven by an electric motor via the automatic transmission. In, the output torque of the engine and the output torque of the electric motor are respectively detected by the torque sensor, and the output torque of the electric motor is controlled so that the total value of the output torque does not change even during the gear shift period. A driving force control device for reducing the driving force is disclosed.

[0006]

The reduction of the shift shock by tuning the accumulator or the like as described above is not enough to reduce the shift shock due to variations in individual automatic transmissions and deterioration of friction engagement members and oil. It is difficult, especially in the case of hybrid vehicles, because the engine and electric motor have different inertias and shift points.
It is difficult to tune to an optimum value at the same time when the engine is driven and when the electric motor is driven.

Further, in the method using the torque sensor described above, the torque sensor is expensive and is made up of large parts, so that it is difficult in terms of cost and installation space, and at the same time, the electric motor is detected after the output torque fluctuation is detected by the torque sensor. However, if the output is controlled, the response delay is apt to occur, and it is difficult to sufficiently reduce the shift shock.

Therefore, the present invention provides an electric motor drive vehicle which solves the above-mentioned problems by predicting the speed change situation from the number of revolutions of the electric motor or the like and controlling the torque of the electric motor so as to reduce the shift shock. That is the purpose.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and the torque of an electric motor (10) is passed through an automatic transmission (9) to drive wheels (33a, 33a,
33b), in an electric motor drive vehicle, a motor rotation detecting means (35) for detecting the rotation speed (Nm) of the electric motor (10), and an output rotation speed (No) of the automatic transmission (9). Output rotation speed detection means (3
6) and the motor rotation speed and output rotation speed detecting means (3
5) and (36), a calculation means (37) for judging the shift condition of the automatic transmission, and a motor torque control means (for controlling the torque of the electric motor (10) based on the calculation of the calculation means (37). 40), and controlling the torque of the electric motor (10) so that the output torque fluctuation of the automatic transmission is smoothed during a shift of the automatic transmission.

[0010]

Based on the above construction, when the automatic transmission (9) is upshifted or downshifted, the automatic transmission (9) is changed in speed by the motor rotation speed detection means (35) and the output rotation speed detection means (36). The situation is predicted and determined by the calculation means (37). For example, when the motor rotation speed (Nm) decreases or increases by a predetermined number with respect to the reference rotation speed based on the output rotation speed (No), the shift is started, and when it reaches another predetermined number, the shift is ended. ,to decide.

By the judgment based on the calculation means (37),
The motor torque control means (40) is an electric motor (10).
The output torque (To) is controlled so that the part that causes a shift shock during the shift is removed.
Smooth the fluctuations of. In addition, the code in the above brackets is
The purpose is to contrast with the drawings, but the structure of the present invention is not limited thereto.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention in which a two-speed automatic transmission composed of an underdrive mechanism (U / D) is connected downstream of the transmission of an engine and an electric motor.

An internal combustion engine 1 such as gasoline or diesel is laterally mounted on a bonnet portion of a hybrid vehicle, a converter housing 2 is fixedly connected to the engine 1, and a transaxle case 3 is further connected. Also, the motor case 5 is integrally fixed. Then, the torque converter 6, the input clutch 7, the second speed automatic transmission 9 are aligned with the engine output shaft 1a.
And an electric motor 10 are arranged, and a differential device 11 is further arranged below the electric motor 10, and these devices are integrally connected to the case (housing) 2,
It is stored in 3,5.

Torque converter 6 which is a fluid transmission device
Is arranged in the converter housing 2 and has a pump impeller 12, a turbine runner 13, a stator 15 and a lockup clutch 16. The pump impeller 12 is connected to the engine output shaft 1a,
Output sides of the turbine runner 13 and the lockup clutch 16 are connected to an input shaft 17. In addition, the stator 15
Is supported on the one-way clutch 19, and the inner race of the one-way clutch 19 is fixed to the housing 2. A hydraulic pump 20 is arranged between the torque converter 6 and the input clutch 7, and the drive gear portion of the pump 20 is connected to the pump impeller 12.

The input clutch 7 comprises a hydraulic wet multi-plate clutch, the input side of which is connected to the input shaft 17 and the output side of which is connected to an intermediate shaft 21 extending toward the automatic transmission 9. . A sleeve-shaped output shaft 22 is rotatably fitted on the intermediate shaft 21, and a counter drive gear 23 is fixed to one end of the output shaft 22 adjacent to the input clutch 7. .

The two-speed automatic transmission 9 is provided with an underdrive mechanism (U / D) having a single planetary gear unit 25 constituting a transmission gear unit, its ring gear R is connected to the intermediate shaft 21, and its carrier CR is It is connected to the output shaft 22. Further, a direct clutch C2 forming a friction engagement member is interposed between the carrier CR and the sun gear S, and a low speed clutch forming a friction engagement member is also formed between the sun gear S and the case 3. The brake B and the one-way clutch F are interposed.

On the other hand, the electric motor 10 is a brushless DC.
It is composed of a hollow motor such as a motor, an induction motor, and a DC shunt motor, and is arranged in the motor case 5. The electric motor 10 has a flat stator 26 and a flat rotor 27.
Is fixed to the inner wall of the rotor and is wound with a coil 28, and the rotor 27 is connected to the ring gear R of the planetary gear unit 25 together with the intermediate shaft 21. Therefore, the electric motor 10 has a large cylindrical hollow portion A extending in the axial direction at the center thereof, and the second speed automatic transmission is provided in the hollow portion A over a part of the axle case 3. A device 9 is arranged.

A counter shaft 29 and a differential device 11 are arranged below the transaxle case 3, and a counter driven gear 30 and a pinion 31 meshing with the drive gear 23 are fixed to the counter shaft 29. . The differential device 11 has a ring gear 32 that meshes with the pinion 31, and the torque from the gear 32 is transmitted to the left and right front wheels 33a and 33b according to the load torque.

Next, the operation of this embodiment will be described.

In the suburbs and highways, in order to drive the vehicle at high speed and over long distances, the engine drive mode is set by an electronic control unit such as a mode changeover switch. In this state, the input clutch 7 is in the connected state based on the hydraulic control circuit (not shown), and the input shaft 17 and the intermediate shaft 21 are connected. The rotation of the engine output shaft 1a is transmitted to the torque converter 6, transmitted to the input shaft 17 via the oil flow or the lockup clutch 16, and further transmitted to the intermediate shaft 21 via the input clutch 7. It Therefore, in the engine running mode, although the output characteristic of the engine 1 is low at low rotation speed, the torque converter 6 automatically and smoothly increases the torque, thereby starting, accelerating and You can smoothly and reliably climb uphill.

The rotation of the intermediate shaft 21 is shifted to the second speed by the automatic transmission 9 based on the throttle opening and the vehicle speed and transmitted to the output shaft 22. That is, in the first speed state, the direct clutch C2 is disengaged and the one-way clutch F is in the locked state. In this state, the intermediate shaft 21
Is transmitted to the ring gear R, and further, based on the sun gear S in the locked state, the carrier CR is decelerated while rotating the pinion P, and the decelerated rotation (U / D) is output to the output shaft 2
2 is transmitted. During engine braking (coast), the brake B is engaged and the sun gear S
To stop.

Then, in the second speed state, the direct clutch C2 is engaged. In this state, the sun gear S and the carrier CR are integrated by the clutch C2, and the gear unit 25 integrally rotates. Therefore, the rotation of the intermediate shaft 21 is directly transmitted to the output shaft 22.

The rotation of the output shaft 22 is transmitted from the counter drive gear 23 to the driven gear 30, and further transmitted to the differential device 11 via the differential drive pinion 32. Further, the differential device 11 transmits differential rotation to the left and right front wheels 33a and 33b, respectively.

The rotation of the engine output shaft 1a is transmitted to the hydraulic pump 20 via the converter case, and the pump produces a predetermined hydraulic pressure. Further, in the engine running mode, the circuit of the coil 28 is open,
In the electric motor 10, the rotor 27 that is integral with the intermediate shaft 21 is idling. The circuit of the coil may be connected to a battery to charge the battery with an electromotive force based on the rotation of the rotor 27, or the battery may be charged by operating as a regenerative brake during braking.

On the other hand, repeatedly start at low speeds such as driving in urban areas.
When stopped, the electric motor drive mode is set by the mode changeover switch, electronic control unit, or the like. In this state, the input clutch 7 is disengaged, and the input shaft 17 and the intermediate shaft 2
When the interlocking of 1 is cut off, a predetermined current is passed through the coil 28 from the motor driver to drive the electric motor 10. Then, the rotation of the rotor 27 of the electric motor 10 will be 2
It is transmitted to the output shaft 22 via the high speed automatic transmission device 9, and further transmitted to the left and right front wheels 33a and 33a via the counter drive gear 23, the driven gear 30, the pinion 31 and the differential device 11.

At this time, the engine 1 is constantly rotating in a predetermined low-speed state in which exhaust gas and noise are little generated, and the rotation of the output shaft 1a is transmitted to the hydraulic pump 20 via the converter case 15 to a predetermined value. Hydraulic pressure is generated. The rotation of the engine output shaft 1a is not transmitted to the intermediate shaft 21 because the input clutch 7 is disengaged.

In the electric motor running mode, when a large load torque is applied at the time of starting, accelerating, or climbing the hill, the automatic transmission 9 is in the first speed state and the electric motor 10 Increase the torque of the front wheel 33
a, 33b, and when a high rotation speed is required for normal traveling or the like, the automatic transmission 9 is in the second speed state and transmits a high speed rotation. Therefore, even if the size of the electric motor 10 is not increased, a predetermined request is required. It can handle torque.

Further, in the electric motor traveling mode, since the torque converter 6 is not used for power transmission, power loss by the torque converter 6 does not occur, and torque can be transmitted to the wheels with high transmission efficiency. Therefore, it is possible to secure a relatively long cruising distance while using a battery having a low energy density. Further, in the electric motor running mode, the electric motor 10 itself has the characteristics of smoothly rising from zero rotation speed to high speed and having high torque at low rotation speed, without passing through the torque converter 6. , Smooth start and acceleration are possible.

In the above-described embodiment, the engine running mode and the electric motor running mode are switched and used.
It may be used as a so-called series (series) type in which only the electric motor is constantly used for traveling and the battery is charged by constantly rotating the engine irrespective of the suburbs or the suburbs. In this case, the input clutch 7 is disengaged, and the engine output shaft 1a is linked to the generator via the hydraulic pressure of the hydraulic pump 20 or a belt transmission device (not shown). In addition, even in the case of this, in an emergency, it is possible to connect the input clutch 7 and run with the output of the engine or with the output of the electric motor assisting the output of the engine.

On the other hand, a rotation speed sensor 35 for detecting the rotation of the rotor 27 of the electric motor 10, that is, the input rotation of the automatic transmission 9, and a rotation speed sensor 36 for detecting the output rotation speed of the automatic transmission are installed. ing. These rotation sensors 35, 36 are, for example, optical, magnetic or contact type pickup sensors set, or the motor rotation speed sensor 35 also serves as a motor control sensor such as an encoder, a hall element or a resolver. Alternatively, these rotation speed sensors may be installed in another place to detect by converting the gear ratio, and the signals from both rotation speed sensors 35 and 36 are controlled as shown in FIG. Sent to device 37.
The controller 37 includes a large number of input / output ports 37a, a CPU 37b, a ROM 37c, a RAM 37.
The CPU is provided with d and the like, and in cooperation with the data of the ROM and the RAM, the CPU calculates the values from the both rotation speed sensors 35 and 36 to judge the shift condition of the automatic transmission 9. Motor driver 4 constituting motor torque control means
Output to 0. As a result, when the automatic transmission 9 shifts (1 → 2, 2 → 1 shift), the electric motor 10 is torque-controlled so as to smooth output torque fluctuations of the automatic transmission.

Next, the torque control of the electric motor will be specifically described with reference to FIGS. It should be noted that this torque control is performed in the electric motor running mode of the hybrid vehicle described above, and when running by an electric motor when used as a series type, that is, when running only by the electric motor and while being assisted by the engine. It works when traveling in. Further, not only the hybrid vehicle but also the electric vehicle in which only the electric motor is mounted together with the automatic transmission function similarly.

3 to 5 show the case where the automatic transmission 9 is upshifted from the first speed to the second speed, that is, the direct clutch C2 is switched from the released state (the first speed) to the engaged state (the second speed). It shows the situation.

FIG. 3 shows upshifts and states when torque control by the electric motor is not performed.
Is the clutch pressure P when the direct clutch C2 is engaged
The change of c is shown. In the figure, A is a clutch C2
Hydraulic pressure until the friction material of the clutch abuts, between A and B the hydraulic pressure from the friction material of the clutch to the start of the operation of the accumulator, C shows the hydraulic pressure until the end of the operation of the accumulator, and Represents the end of the clutch piston stroke, the point represents the end of the torque phase (between; torque phase), and the point represents the end of the inertia phase (between; inertia phase).

At this time, the output torque To is, as shown in FIG. 3 (b), the clutch C2 in the torque phase (-).
The torque of the one-way clutch F, which is a reaction force element, decreases with an increase in the torque of 1) and decreases, and becomes the same value as the motor torque Tm (FIG. 3 (d)), that is, the input torque at a point. Up to this point, one-way clutch F
Since the elements are engaged with each other, the speed of each element does not change, and the inertia torque is not generated. However, when the torque phase ends () and enters the inertia phase (-), the one-way clutch F
Is released, the reaction force becomes zero, and inertia torque is generated as the rotational speed of each element changes. Due to the influence of the inertia torque, the output torque To increases over the inertia phase (-) as indicated by Y, and at the point, the clutch C
2 is completely engaged and coincides with the motor (input) torque Tm.

At this time, as shown in FIG. 3 (c), the motor rotation speed Nm is temporarily reduced by changing the gear ratio based on the upshift, and the output rotation speed No is set to increase the traveling speed. , At the point where the engagement of the direct clutch C2 is completed, both rotational speeds No and Nm match. In addition, at the time of the upshift, the motor characteristic is as shown in FIG.
As shown in (e), the torque T decreases as the rotation speed Nm decreases.
Since m increases linearly, as shown in Fig. 3 (d),
The motor torque Tm gradually increases from the gear shift start point toward the gear shift end point, and coincides with the output torque To at the point.

At the output torque To described above, as shown in FIG.
As indicated by Y in (b), the fluctuation of the inertia phase (-) affected by the inertia torque is large, which adversely affects the shift shock. Further, the conventional torque sensor uses the torque fluctuation Y in the inertia phase (-) to control the motor torque, so that the torque control is performed after the point, resulting in a response delay. In FIG. 3 (b), the alternate long and short dash line shows the change in the torque ratio, and the broken line shows the change in the motor (input) torque (see FIG. 3 (d)).

FIG. 4 is a diagram showing a state in which torque control is performed by the electric motor according to the present invention in order to improve the shift shock, and FIG. 5 shows the control flow thereof.

First, in step S1 of FIG. 5, it is determined whether or not the upshift command state is currently set based on the shift line diagram including the accelerator opening degree and the vehicle speed. If the upshift command state is set, the automatic shift is performed in step S2. It is determined that the hydraulic circuit of the apparatus starts the upshift operation, that is, is in the command state of supplying hydraulic pressure to the hydraulic servo of the direct clutch C2.

Then, as shown in FIG. 4 (c), when the direct clutch C2 has started contact (torque phase-), the inertia phase is entered and the one-way clutch F is disengaged. (Input) Speed Nm
Transmits the rotation while sliding with the direct clutch C2, and thus starts decreasing. The decrease in the motor rotation speed is detected by monitoring the motor rotation speed sensor 35. Specifically, the rotation speed of the sensor 35 is stored and it is determined that the previous storage value is compared with the current value to determine that the rotation speed has decreased, or the rotation speed No of the output rotation speed sensor 36 indicates the first speed state. The input rotation speed in the completely connected state is calculated by multiplying the gear ratio of
Is compared with the actual rotation speed of the motor to determine the point at which the motor rotation speed has started to decrease.

Then, as shown in FIG. 4 (c), in order to confirm that the motor rotation speed Nm surely decreases, the deceleration rotation speed ΔNm1 is preset and the predetermined rotation speed ΔNm1 is set. Is detected by the motor rotation speed sensor 35 as described above, it is determined that the inertia phase (-) has been entered (S3), and torque correction breakdown of the electric motor is started (point a in FIG. 4). As shown in FIG. 4 (d), the torque correction control operates to decrease the normal motor torque Tm0 shown by the broken line (see FIG. 3 (c)) by a predetermined amount ΔTm (Tm = Tm0− ΔTm). The motor torque correction amount ΔTm is ΔTm = α · Nm · (ΔNo−ΔN) / ΔNo α; a constant ΔNo determined from the inertia of the rotating system ΔNo; the difference between the motor rotation speed at the correction control start point a and the output rotation speed ΔN; It is determined by the mathematical expression of the difference between the rotation speed Nm and the output rotation speed No.

When the motor torque correction control is started in step S3, a signal is output to the motor torque command value Im in step S4 so as to subtract the predetermined amount x from the current value Im for each circulation. The predetermined amount x is determined by the motor torque correction amount ΔTm. Therefore, the motor torque command value Im is a value that generally decreases linearly with a predetermined gradient from the correction control start position a as shown in FIG. 4 (e).

Then, as shown in step S5, when the difference ΔN between the motor rotation speed Nm and the output rotation speed No reaches a preset predetermined value ΔNm2, that is, when ΔN ≧ ΔNm2, the inertia is soon reached. It is determined that the phase ends, and the motor torque correction control is stopped (b in FIG. 4).
point). In this state, as shown in step S6, the motor torque value Im is returned to the original value Im0 before the correction control was started.

As a result, as shown by the broken line Y in FIG. 4 (b), a large output torque fluctuation due to the influence of inertia is
The motor torque Tm is absorbed by being corrected in the decreasing direction, and the output torque To is smoothed as shown by the solid line. Therefore, at the time of 1 → 2 upshift, the output torque To
Is held substantially flat, and the shift shock is almost eliminated.

Next, the state in which the automatic transmission 9 is downshifted from the second speed to the first speed, that is, the state in which the direct clutch C2 is released and the one-way clutch F is engaged will be described with reference to FIGS.

FIG. 6 shows a situation at the time of downshifting when the torque control of the electric motor according to the present invention is not carried out. When the operator pushes the accelerator, a motor torque command is issued as shown in (a). The value Im increases, and as a result, the motor torque Tm also increases (), as shown in (e).

At the same time, the hydraulic control circuit is also switched so that the direct clutch C2 is released from the engaged state.
The oil pressure of the clutch changes as shown in FIG. 6 (b).
That is, the clutch hydraulic pressure Pc does not change until the hydraulic pressure of the accumulator starts to drain, and then the hydraulic pressure from the accumulator drains, whereby the hydraulic pressure drops while the piston moves (D). Furthermore, when the accumulator piston stroke ends, the hydraulic pressure of the clutch hydraulic servo decreases while the piston moves (E).

At this time, as shown in FIG. 6 (c), the output torque To changes with the motor torque Tm and sharply increases even after the gear shift command because the direct clutch C2 is in the connected state. After that it will be constant. Then, when the hydraulic pressure is completely drained from the accumulator and the clutch C2 is released, the output torque To suddenly becomes 0, but in reality, as shown by G, the output torque To is inclined by the residual pressure due to the centrifugal force acting in the hydraulic servo. Decrease. Then, when the one-way clutch F is engaged, a reaction force acting on the planetary gear unit is received, and the output torque To is rapidly recovered (), but at this time, the abrupt engagement of the one-way clutch F causes torque fluctuations. Z is generated.

On the other hand, the rotation speed N is the motor rotation speed N because the planetary gear unit is integrally rotated by the engagement of the clutch C2 until the clutch is disengaged ().
m, the output rotational speed No, and the rotational speed Ns of the sun gear S, which is a reaction element, are the same, and these are separated after the clutch is released. That is, the output rotation speed No is substantially constant, the sun gear rotation speed Ns is stopped by the engagement of the one-way clutch F, and the motor rotation speed Nm is increased by the gear ratio. At this time, the motor characteristics change as shown in FIG. 6 (f).

The output torque fluctuation Z at the time of engagement () of the one-way clutch F described above adversely affects the shift shock at the time of downshifting.

FIG. 7 shows a method for improving the shift shock.
It is a figure which shows the state which performed the torque control of the electric motor which concerns on this invention, and FIG. 8 shows the control flow.

First, in step S7 of FIG.
In step 7, it is determined from the gear shift diagram whether or not the downshift command state is present. If the downshift command is issued, the downshift operation of the hydraulic control circuit is started (S8). During the downshift operation, the sensor 35 detects the rotation speed Nm of the motor and the sensor 36 outputs the output rotation speed Nm.
o is detected, and the input rotation speed NmF is calculated by multiplying the output rotation speed by the gear ratio, and both rotation speeds Nm and NmF are compared.

Then, as shown in FIG. 7 (d), when the difference between the two rotation speeds becomes equal to or less than a predetermined rotation speed ΔN1 (for example, 100 rpm), it is soon determined that the one-way clutch F is engaged (). That is, as shown in step S9, when Nm> NmF-ΔN1, the relief control of the electric motor torque control is started. In the relief control, as shown in step S10, the motor torque command value Im is decreased by a preset value ΔIm for a predetermined time (Im = Im−ΔIm). As shown in FIG. 7A, this state is kept constant (cd) until the calculated value shown below is reached, and the motor torque Tm is kept low during this period, so that the motor rotation speed Nm It has the effect of alleviating a sharp rise.

Then, as shown in step S11, the difference between the motor (input) rotation speed Nm and the converted rotation speed NmF based on the output rotation speed No is a predetermined value ΔN2 (eg, 50).
rpm (d) (Nm> NmF-ΔN2), the motor torque command is Im ← I as shown in step S12.
m + u, which is gradually increased by a predetermined amount u for each circulation. Thereby, the motor torque command value Im and the motor torque Tm
Is gradually increased from the d position as shown in FIGS. 7 (a) and 7 (e). The motor torque command value Im is ΔIm.
The time (cd) during which the reduced constant value is maintained is while the motor rotation speed Nm is NmF-ΔN1 <Nm <NmF-ΔN2.

Then, when the preset time set in step S11 ends (S13), the motor torque command value Im is returned to the value Im0 before the relief control is started, and the motor torque Tm is also increased. , As shown in FIG. 7E, the relief control by the torque control ends.

As a result, as shown by the broken line Z in FIG. 7C, the torque fluctuation due to the engagement of the one-way clutch F is
Smoothing is performed as indicated by the solid line, and shift shock during downshifting is reduced.

Although the above embodiment has been described with respect to the driving of the electric motor of the hybrid vehicle using both the electric motor and the engine, it can be similarly applied to the driving of the engine. Further, it is needless to say that the same can be applied to an electric vehicle equipped with only an electric motor.

Further, as the automatic transmission, the 2nd speed shift by the underdrive and the direct drive has been explained, but the 2nd speed shift by the direct drive and the overdrive, the 2nd speed shift by the different combination of the planetary gears, and the 3rd speed, the 4th speed. It can be applied to the above-described multi-stage gear shift similarly.

[0059]

As described above, according to the present invention,
The speed of the electric transmission and the output speed of the automatic transmission are used to judge the speed change condition of the automatic transmission, and the motor torque is controlled so that the output torque is smoothed. The shift shock can be reduced.

Further, the torque control is performed by predicting the gear shift situation based on the number of revolutions of the electric motor, so that a response delay does not occur and the shift shock can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a drive device in a hybrid vehicle to which the present invention can be applied.

FIG. 2 is a control block diagram according to the present invention.

FIG. 3 is a diagram showing changes with time during an upshift of the automatic transmission, showing a state in which electric motor torque control according to the present invention is not performed.

FIG. 4 is a view similar to FIG. 3 in a state where electric motor torque control according to the present invention is performed.

FIG. 5 is a diagram showing a control flow during an upshift.

FIG. 6 is a diagram showing changes over time during downshifting of the automatic transmission, showing a state in which electric motor torque control according to the present invention is not performed.

FIG. 7 is a view similar to FIG. 6 in a state where electric motor torque control according to the present invention is performed.

FIG. 8 is a diagram showing a control flow at the time of downshifting.

[Explanation of symbols]

 9 Automatic Transmission 10 Electric Motors 33a, 33b Drive Wheels 35 Motor Rotation Speed Detection Means (Sensor) 36 Output Rotation Speed Detection Means (Sensor) 37 Computing Means (Control Device) 40 Motor Torque Control Means (Motor Driver) Nm Motor (Input) ) Rotation speed No Output rotation speed Tm Motor torque To output torque Im Motor torque command value

Claims (1)

[Claims] 1. In an electric motor drive vehicle for transmitting torque of an electric motor to a drive wheel through an automatic transmission, motor rotation detecting means for detecting a rotation speed of the electric motor, and output rotation of the automatic transmission. Output rotation speed detection means for detecting the number of rotations, calculation means for judging the shift status of the automatic transmission based on the motor rotation speed and output rotation speed detection means, and the electric motor of the electric motor based on the calculation of the calculation means. A motor torque control means for controlling torque, wherein the torque of the electric motor is controlled so that the output torque fluctuation of the automatic transmission is smoothed during a shift of the automatic transmission. .