JPH0564304A - Regenerative brake system for motor vehicle - Google Patents

Abstract

PURPOSE:To effect regenerative brake even when an acceleration signal is zero under high speed driving and to realize smooth switching between regenerative brake mode and driving mode by deciding a decelerating state based on the rotational speed of motor and the acceleration signal and then controlling the extent of regenerative brake according to thus decided decelerating state. CONSTITUTION:Output voltages thetaTH, Ne of an accelerator opening sensor 42 and a rotational speed sensor 90 are read in by operating an accelerator grip 41. A mode decision table is then referred to and a mode is decided based on thus read in output voltages thetaTH and Ne. Upon decision of regenerative brake mode, a regenerative brake duty ratio table is referred to and a regenerative brake duty ratio is read out based on the output voltage thetaTH with the output voltage Ne as a parameter. FETs 44a-44f are then turned ON/OFF with thus read out duty ratio through a switching circuit 45 thus performing output processing required for regenerative brake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative braking system for an electric vehicle, and more particularly to a regenerative braking system for an electric vehicle that regeneratively brakes in accordance with a deceleration state determined based on a motor speed and an accelerator signal.

[0002]

2. Description of the Related Art As is well known, an electric vehicle is equipped with an electric motor for driving the vehicle, and the electric motor is powered by a battery to run. In such an electric vehicle, regenerative braking is performed during braking, the kinetic energy of the vehicle is recovered as electric power, and the battery is charged.

On the other hand, when the accelerator signal decreases in order to provide the electric vehicle with a function equivalent to the engine brake of an internal combustion engine vehicle, the differential value is taken, and the period is switched to the regenerative braking state according to the differential value. It has been proposed to put an electric vehicle in a braking state for a certain period (Japanese Patent Publication Sho 52).
-12446 gazette).

[0004]

However, according to the above-mentioned conventional regenerative braking system, when the accelerator signal is returned to zero during high speed traveling, regenerative braking works only for a period corresponding to the differential value of the accelerator signal, After that period, there was a problem that regenerative braking did not work even though the speed was increasing and the accelerator signal was zero.

Further, since the drive mode and the regenerative braking mode are switched on and off at the boundary corresponding to the differential value, there is a problem that the regenerative braking cannot be smoothly performed.

The present invention has been made in view of the above, and determines the deceleration state from the motor rotation speed and the accelerator signal, and controls the strength of regenerative braking in accordance with the determined deceleration state to allow high-speed running. Even when the accelerator signal is zero, regenerative braking works, and the switching between the regenerative braking mode and the drive mode is smooth, and a regenerative braking system for an electric vehicle that provides a function corresponding to the engine brake of an internal combustion engine vehicle is provided. The purpose is to provide.

[0007]

A regenerative braking system for an electric vehicle according to the present invention comprises a rotation sensor for detecting the number of rotations of a motor,
An accelerator opening sensor, a discriminating means for discriminating between the regenerative braking mode and the drive mode based on the motor rotational speed and the accelerator opening, and on / off duty ratio information of the switching element of the inverter in the regenerative braking mode. Storage means stored corresponding to the number of revolutions and the accelerator opening,
When it is determined that the regenerative braking mode is determined by the determination means, the on / off duty ratio information corresponding to the motor rotation speed and the accelerator opening is retrieved from the storage means, and the on / off corresponding to the retrieved on / off duty ratio information. And a control unit that controls the switch element with a duty ratio to perform regenerative braking.

Further, the discrimination boundary between the regenerative braking mode and the driving mode in the discrimination means may be in the vicinity of the motor driving force zero line.

[0009]

According to the regenerative braking device for an electric vehicle of the present invention, when it is determined that the regenerative braking mode is in correspondence with the motor rotation speed and the accelerator opening, the motor rotation speed and the accelerator opening are stored in the storage means. The on / off duty ratio information is retrieved, the switch element is controlled by the on / off duty ratio based on the retrieved on / off duty ratio information, and regenerative braking is performed.

Therefore, regenerative braking can be made to work even when the accelerator opening is zero during high-speed running, and the on / off duty ratio at the boundary between the regenerative braking mode and the drive mode in the determining means can be changed. By reducing the change, even when the regenerative braking mode and the drive mode are switched to each other, the switching is smoothly performed and a sudden change feeling is not given.

[0011]

EXAMPLES The present invention will be described below with reference to examples.

This embodiment exemplifies a case where the present invention is applied to an electric motorcycle.

FIG. 1 is an overall side view of an electric motorcycle V according to the present invention. A vehicle body frame F is composed of a front frame F ₁ made of steel pipe, a central frame F ₂ and a rear frame F ₃ , and the outside thereof. Is covered by a body B made of synthetic resin, which is composed of a leg shield B ₁ , a step floor B ₂ , a rear cover B ₃ and an under cover B ₄ . The head pipe 1 fixed to the front frame F ₁ is pivotally supported by a front fork 4 having a steering handle 2 at the upper end and a front wheel Wf mounted on the lower end via a front cushion 3.

At the rear of the central frame F ₂ , a front end of a swing type power unit P as a rear fork having a rear wheel Wr mounted cantilevered at the rear end is pivotally supported by a pivot 5 so as to be vertically swingable. The rear upper surface of the power unit P and the rear frame F ₃ are connected via a rear cushion 6.

The stand 7 provided on the central frame F ₂ is
It covers the lower surface of the front portion of the power unit P at the storage position shown in the drawing, and also serves as a protective member for a drive motor, which will be described later, housed inside the power unit P. Above the power unit P, there is provided a storage section 9 which is opened and closed by a seat 8 which is supported by the vehicle body so as to be vertically swingable.

The storage portion 9 is formed of a material such as a conductive resin that shields the magnetism so that the magnetic field generated by the motor does not affect the stored contents such as the floppy disk.

The central frame F ₂ is provided with a battery box 10 for storing a battery 10A as a power source for driving the motor. Further, in front of the head pipe 1, a controller 11 for controlling driving of a motor and a charger 12 for charging the battery 10A are provided.

Next, the structure of the power unit P will be described in detail with reference to FIG. The power unit P is provided with a transmission case 13 at the front end thereof, through which the pivot 5 penetrates left and right, and a motor M provided at the front portion thereof and a reduction gear 1 provided at the rear portion thereof.
4 are connected via a belt type continuously variable transmission 15.

The motor M is housed inside a motor housing 16 formed integrally with the front part of the transmission case 13, and the opening on the right side surface thereof is closed by a lid member 18 fixed with a bolt 17. The rotary shaft 19 of the motor M is supported by a ball bearing 20 provided on the lid member 18 and a ball bearing 21 provided on a wall portion 16 ₁ at the left end of the motor housing 16.

A cooling fan 22 is provided at the right end of the rotary shaft 19 projecting from the lid member 18, and the outer periphery thereof is covered with a fan cover 23 having an air intake 23 ₁ . And
The air introduced from the air inlet 23 ₁ by the cooling fan 22 flows into the inside of the motor housing 16 through the through hole 18 ₁ of the lid member 18, cools the motor M, and then the through hole of the wall portion 16 ₁ . It is supplied from 16 ₂ into the transmission case 13.

The air further flows rearward in the transmission case 13 to cool the belt type continuously variable transmission 15, and then is discharged to the outside from an air outlet 13 ₁ formed at the rear end of the transmission case 13. On the other hand, the wall portion 16 of the motor housing 16
Rotating shaft 19 penetrating ₁ and extending inside the transmission case 13
The left end of is directly used as the input shaft of the belt type continuously variable transmission 15.

The motor M is a DC brushless motor and has a permanent magnet 3 on the outer periphery of an iron core 31 fixed to the rotary shaft 19.
2 is wound around a rotor 33 and an iron core 35 fixed to the inside of the motor housing 16 with bolts 34,
A rotor position is provided with a stator 37 including Y-connected coils 36U, 36V, and 36W, and a magnet 38 fixed to the rotating shaft 19 and three Hall elements 39 arranged so as to face the outer periphery of the magnet 38. A sensor 40 and a rotation speed sensor 90 that detects the rotation speed of the motor M are provided.

The rotation speed sensor 90 is composed of a magnet fixed to the rotating shaft 19 and an MR provided to face the outer circumference of the magnet.
It is composed of a magnetically sensitive element such as an element.

FIG. 3 is a circuit diagram showing the control system of the motor M.
In order to control the rotation speed of the motor M, the output potential of the accelerator opening sensor 42, which is a potentiometer for detecting the rotation angle of the accelerator grip 41 of the steering handle 2, and the rotor detected by the rotor position sensor 40. 33
Is input to the controller 11, and the output of the rotation speed sensor 90 is input to the controller 11 to regeneratively brake the motor M.

Further, between the controller 11 and the motor M
A driver 43 controlled by the output of the controller 11 is installed.
Each driver 43 has a diode D._a
~ D _fField-effect transistors connected in parallel
(Hereinafter abbreviated as FET) 44a to 44f and RO
Based on the on / off duty ratio information stored in M112
The FET44 group by controlling the stator current of the motor M.
And a switching circuit 45 for sequentially switching
It Here, the controller 11 and the FETs 44a to 44
f, the switching circuit 45 cooperates to form an inverter
is doing.

The controller 11 includes a central processing unit (C
PU) 111, ROM 112 storing programs, and RAM 113 having a work area. ROM11
2, a mode discrimination table storing mode discrimination information for discriminating the drive / regenerative braking mode based on the output voltage Ne of the rotation speed sensor 90 and the output voltage θ _TH of the accelerator opening sensor 42 (see FIG. 11). ), A drive duty ratio table storing drive duty information based on the output voltage Ne and the output voltage θ _TH (see FIG. 12), and a regenerative braking duty ratio storing regenerative duty information based on the output voltage Ne and the output voltage θ _TH. Table (see Figure 13)
Is stored.

Therefore, the mode discrimination table is referred to and the mode is discriminated based on the output voltage Ne and the output voltage θ _TH, and the drive duty ratio table is referred to in the drive mode corresponding to the discriminated mode. The drive duty ratio is read out by referring to the regenerative braking duty ratio table in the regenerative braking mode.

As shown in FIGS. 4 to 9, at the tip of the handle pipe 46 on the right side of the steering handle 2, an accelerator grip comprising a substantially cylindrical rotary bracket 47 and a grip body 48 integrally fitted to the outer periphery thereof. 41 is rotatably supported.

On the other hand, in the vicinity of the base of the accelerator grip 41 of the handle pipe 46, an upper cover 49 and a lower cover 50 which are vertically divided into two are mounted. Both covers 4
Reference numerals 9 and 50 include small-diameter mounting portions 49 ₁ and 50 ₁ supported by the handle pipe 46, and large-diameter storage portions 49 ₂ and 50 ₂ that cover the accelerator opening sensor 42.
The lower cover 5 is attached to the opening 49 ₃ formed in the mounting portion 49 _{1 of the} 9
The protrusions 50 ₃ of 0 are engaged with each other through the bolts 51 and are fixed to the handle pipe 46 by the other bolts 52.

The flange 47 ₁ formed at the base of the rotating bracket 47 of the accelerator grip 41 is provided on both covers 4.
It extends inside the accommodating portions 49 ₂ and 50 ₂ of 9 and 50, and is locked to one end of a torsion spring 53 wound around the outer circumference of the handle pipe 46. As a result, the accelerator grip 41 is
The stopper surface 47 ₂ formed on the flange 47 ₁ has an operating member 8 of the brake switch 81 provided on the lower cover 50.
It is urged in the direction of arrow a toward the unloaded position where it abuts the second stopper surface 82 ₁ (see FIG. 8).

The actuating member 82 is larger than the torsion spring 53.
Due to the strong spring 83, the elastic force of the torsion spring 53
The accelerator grip 41 is biased in the opposite direction.
Flange 47 with hand released₁And actuation
The member 82 stops at the position shown. At this time, the operating member
Conductor 82 provided on 82₂Is a pair of contacts 84₁, 84 ₂
The brake switch 81 is located at a position shown in FIG.
Is off, but accelerator grip 41 is unloaded
Beyond the position, resist the spring 83 and expose in the direction of arrow a.
When rotated to the₁Is pressed by the operating part
As the material 82 descends, its conductor 82₂Through
Both contacts 84₁, 84₂And the brake switch 8
1 works. Turn on the brake switch 81
For example, the load and rotation angle are 10 kgf / cm and
And 4 ° is appropriate.

The schematic annular stationary housing 55 which is bolted 54 to the lower surface of the lower cover 50 disposed so as to surround the outer periphery of the handle pipe 46 in the housing portion 49 _2, 50 ₂ of the covers 49, 50 To be done. Fixed housing 5
A printed circuit board 56 is integrally provided in the inside of 5, and a resistor 56 ₁ and a conductor 56 ₂ described later are printed on one surface thereof.

Inside the fixed housing 55, there is provided a brush 57 having _two contacts 57 ₁ and 57 ₂ which are in sliding contact with the printed circuit board 56, and a part of the inner circumference is a metal cylinder 58 _3.
A rotary housing 58 reinforced by is housed therein. Both housings 55, 58 are relatively rotatable via a pair of seals 59, and the annular projection 5 provided on the rotary housing 58.
8 ₁ is engaged with an annular groove 55 ₁ provided in the fixed housing 55 so as to be immovably coupled in the axial direction.

Then, two engaging projections 58 axially formed on the rotary housing 58 are provided in engaging holes 47 ₃ provided at two positions on the flange 47 ₁ of the rotating bracket 47.
₂ fits loosely with a slight gap. This prevents the axial play of the accelerator grip 41 from being transmitted to the rotary housing 58 while transmitting the rotation of the accelerator grip 41 to the rotary housing 58.

As will be apparent by referring also to FIG.
Further, the brush 57 facing the printed circuit board 56 is about 15 °.
It is formed in an arc shape with a central angle of
A substantially circular resistor 56 printed on the printed circuit board 56₁Left of
Half and substantially semicircular conductor 56 ₂All of the brushes
57 are arranged along the moving path.

[0036] In Thus, when in the unloaded position rotated in the forward position by the elastic force of the accelerator grip 41 is the torsion spring 53, i.e. the stopper surface 47 ₂ of the rotary bracket 47 of the lower cover 50 in FIG. 8 When the brush 57 is in contact with the stopper surface 50 ₄ , the brush 57 is at the position shown by the solid line in FIG. 10, and the two contacts 57 ₁ and 57 ₂ thereof both come into contact with the conductor 56 ₂ and therefore the resistor 56 ₁ And conductor 56 ₂
Is cut off and the electric resistance value between the terminals 56 ₃ and 56 ₄ becomes infinite.

When the accelerator grip 41 is rotated toward the front position against the torsion spring 53, that is, in the direction of arrow b in FIGS. 8 and 10, the contact 57 ₁ causes the resistor 56 ₁ to move.
, And the electrical resistance between the terminals 56 ₃ and 56 ₄ becomes large including most of the left half of the resistor 56 ₁ α.

When the accelerator grip 41 is further rotated, the brush 57 is moved to the full load position shown by the chain line in FIG. 10, and the electric resistance between the terminals 56 ₃ and 56 ₄ is changed to the resistor 56.
_It is a small one containing only the lower part β of the left half of ₁ .

[0039] In Thus, the both terminals 56 _3, 56 between ₄ corresponds to the full load position from the unloaded position, for example 0V~5
The voltage of V is output.

Reference numeral 50 ₅ in FIG. 7 is a drain hole, and reference numeral 60 in FIGS. 5 and 7 is a terminal 56 _3.
Is a lead line connected to to 56 _5.

Next, referring again to FIG. 2, the transmission case 13
The structure of the belt type continuously variable transmission 15 housed inside will be described. The belt type continuously variable transmission 15 includes a drive pulley 61 provided on a rotating shaft 19 protruding from the motor housing 16 side into the transmission case 13, and a driven pulley provided on a speed reducer input shaft 62 supported at a rear portion of the transmission case 13. 63, and an endless belt 64 is wound around both pulleys 61, 63.

The driving pulley 61 is composed of a fixed pulley half 61 ₁ fixed to the rotary shaft 19 and a movable pulley half 61 ₂ axially slidably supported on the rotary shaft 19.
A centrifugal weight 66 is disposed between the movable pulley half 61 ₂ and the ramp plate 65 fixed to the rotary shaft 19 so as to be movable in the radial direction.

On the other hand, the driven pulley 63 is the reduction gear input shaft 62.
Is rotatably fitted to the needle bearing 67
Fixed pulley half 63 supported by collar 68₁And yes
Drive side pulley half 63₂And this driven pulley 63
The driving force transmitted to the front is transmitted through the automatic centrifugal clutch 69.
It is transmitted to the speed reducer input shaft 62. And the belt
Housing the continuous variable transmission 15 and the automatic centrifugal clutch 69
The side of the transmission case 13 has a removable cover 13 again.
₂Is blocked by. The automatic centrifugal clutch 69 is normally
Since the rotation of the motor M is transmitted to the rear wheel Wr during traveling,
That is, the rotation of the driven pulley 63 is transmitted to the speed reducer input shaft 62.
First clutch 69 for₁And the engine braking effect
The rotation of the rear wheel Wr is transmitted to the motor M to obtain the result.
That is, the rotation of the speed reducer input shaft 62 is controlled by the driven pulley 63.
Second clutch 69 for transmission to ₂And consists of
It

The reduction gear input shaft 62 is supported by a ball bearing 70 provided on the transmission case 13 and a ball bearing 72 provided on the reduction gear cover 71, and a pair of balls similarly provided on the transmission case 13 and the reduction gear cover 71. Axle 7 of rear wheel Wr supported by bearings 73, 74
An intermediate shaft 76 is supported between the shafts 5 and 5. The rotation of the input gear 77 of the reduction gear input shaft 62 is transmitted to the output gear 80 of the axle 75 via the two intermediate gears 78 and 79 of the intermediate shaft 76.

Next, the operation of this embodiment having the above construction will be described.

When the accelerator grip 41 is rotated from the unloaded position to the front side to start the motor M, the first clutch 69 ₁ of the automatic centrifugal clutch 69 is engaged and the driving force of the motor M is transmitted to the rear wheel Wr. It At this time, the reduction ratio of the belt type continuously variable transmission 15 is in the maximum state, but the centrifugal weight 66 is radially outward along the ramp plate 65 fixed to the rotation shaft 19 thereof due to the increase in the rotation speed of the motor M. Move to the movable pulley half of the drive pulley 61 ₂
Is moved toward the fixed pulley half 61 ₁ .

[0047] By this movement, leading to an increased effective radius of the drive pulley 61, the movable pulley half 63 ₂ fixed pulley half 63 of the driven pulley 63 via the endless belt 64 at the same time
As a result of being driven in a direction away from _1, and the effective radius thereof is reduced, the reduction ratio of the belt type continuously variable transmission 15 is reduced, the rotational speed of the rear wheels Wr is increased, and the vehicle body is accelerated.

As shown in the flowchart of FIG. 15, the output voltage θ _TH and the rotation of the accelerator opening sensor 42 are controlled by operating the accelerator grip 41 between the no-load position and the full-load position following the start of driving the motorcycle. Number sensor 9
The output voltage Ne of 0 is read (steps S1 and S2). Subsequent to step S2, the mode discrimination table is referred to, and mode discrimination is performed based on the read output voltages θ _TH and Ne (step S3). Step S3
At output voltage θ _TH and Ne at
When the vehicle enters the area B, the drive mode is determined, and when the area B is entered, the regenerative braking mode is determined.

When the drive mode is determined in step S3, the drive duty ratio table is subsequently referred to and the drive duty ratio is read based on the output voltage θ _TH using the output voltage Ne as a parameter (step S).
4). The FETs 44a to 44f are ON / OFF controlled via the switching circuit 45 at a duty ratio based on the drive duty ratio read in step S4, the motor M is energized, and the motor M is rotationally driven (step S5). As a result, the vehicle speed is controlled.

If the regenerative braking mode is determined in step S3, the regenerative driving duty ratio table is referred to following step S3, and the regenerative braking duty ratio is read based on the output voltage θ _TH using the output voltage Ne as a parameter. (Step S6). The FETs 44a to 44f are ON / OFF controlled via the switching circuit 45 at a duty ratio based on the regenerative braking duty ratio read in step S6, and an output process for performing regenerative braking is performed (step S7).

In the output processing of the regenerative braking, the duty ratio of the drive pulse of the FETs 44a to 44c is set to 0, and the FET4
The duty ratio of the drive pulse of 4d to 44f is set to the regenerative braking duty ratio. As a result, the FETs 44a to 44c are turned off, and the FETs 44d to 44f are on / off controlled according to the regenerative braking duty ratio, and the electromotive force generated in the motor M is applied to the battery 10A to be charged.

For this charging, for example, the voltage induced in the coil 36U and the coil 36V will be described. When the voltage of the battery 10A is lower than this induced voltage, the current due to this induced voltage is the coil 36U, the diode Da, and the battery 10A. , The diode De and the coil 36V. When the voltage of the battery 10A is high, the current caused by the voltage induced in the coils 36U and 36V is the coil 36U, the FET 44d, the diode De, and the coil 3.
It flows at 6 V and is dissipated as heat.

Here, it is desirable to reduce the change in the on / off duty ratio at the boundary between the regenerative braking mode and the drive mode in the mode discrimination table. In addition,
The power corresponding to the output voltage θ _TH and the output voltage Ne is shown in Fig. 1.
4 and the thick line shows the case where the power is zero. The boundary between the regenerative braking mode and the drive mode in the mode discrimination table is set near power zero, that is, the on / off duty ratio is near zero.

By setting in this way, even when the drive mode and the regenerative braking mode are switched to each other, the change in the on / off duty ratio is small, and smooth switching is performed. I don't feel. As a result, the electric motorcycle is braked with a deceleration torque according to the regenerative duty ratio and the rotation speed of the motor M.

In FIG. 14, θ indicates running resistance, for example, the angle of a slope.

Now, during the running resistance of θ = 0, the accelerator opening degree (driving power P ₁ ) of the output voltage θ _Th = 100%
Operate the accelerator grip 41 while driving at the output voltage θ
_For example, when moving to an accelerator opening degree of _Th = 40%, as shown by the thick broken line in FIG. 14, the driving power P ₁ once decreases beyond the driving power zero, and θ _Th = 40% of the line. Along with the driving power P ₂ . In this case, the drive mode is discriminated during the period from the drive power P ₁ to zero drive power, and the FETs 44a to 44f are turned on at the duty ratio according to the drive duty ratio table.
The motor M is driven under off control.

During the period when the driving power is reduced to zero or less, the regenerative braking mode is discriminated, and the FETs 44a to 44f are on / off controlled by the duty ratio according to the regenerative duty ratio table to perform the regenerative braking process. Further, in the period from the time when the drive power becomes zero to the drive power becomes positive again until the drive power becomes P ₂ , the drive mode is discriminated and the drive control process according to the drive duty ratio table is performed.

Since the drive power is zero when the current value I flowing through the motor M is zero, the current value flowing through the motor M may be near zero at the boundary between the drive mode and the regenerative mode.

When the rider grips and operates the accelerator grip 41, the accelerator grip 41 rotatably attached to the tip of the handle pipe 46 moves slightly in the axial direction due to the play. In this case, storage unit 49 _2, 50 of the flange 47 ₁ also upper cover 49 and lower cover 50 which is formed in the rotation bracket 47 of the accelerator grip 41
_Although it moves in the axial direction within ₂ , the flange 47 ₁ and the rotary housing 58 are engaged with each other via the engaging hole 47 ₃ and the engaging projection 58 ₂ so as to be relatively movable in the axial direction. Is engaged with the fixed housing 55 through the annular projection 58 ₁ and the annular groove 55 ₁ so as to be immovable in the axial direction, so that the play of the accelerator grip 41 is not transmitted to the rotary housing 58.

As a result, the brush 57 provided on the rotary housing 58 is connected to the printed circuit board 5 provided on the fixed housing 55.
The sliding angle of the accelerator grip 41 is 6 and the rotation angle of the accelerator grip 41 is accurately detected.

When the motor M is regeneratively braked as described above, the motor M functions as a generator, so that the kinetic energy of the vehicle body can be converted into electric energy. Therefore, by using this electric energy for charging the battery, the battery can be downsized.

In the above embodiment, the case of the electric two-wheeled vehicle is illustrated, but the present invention can be applied to the electric three-wheeled vehicle and the four-wheeled vehicle.

[0063]

As described above, according to the present invention, the regenerative braking mode is discriminated based on the motor rotational speed and the accelerator opening degree, and when the regenerative braking mode is discriminated, the switching element of the inverter is set to the motor rotational speed. Regenerative braking is performed by controlling the on / off duty ratio according to the accelerator opening, so regenerative braking can work even when the accelerator opening is zero during high-speed driving, and the accelerator opens when speed is high. There is no longer a case where regenerative braking cannot be applied even though the degree is zero, and regenerative braking equivalent to engine braking of an internal combustion engine vehicle can be obtained.

Furthermore, even if the regenerative braking mode and the driving mode are switched to each other by reducing the change in the on / off duty ratio at the boundary between the regenerative braking mode and the driving mode, the switching is smoothly performed. It does not give a big fluctuation.

Further, when the boundary between the regenerative braking mode and the driving mode is set near the motor driving force of zero, the mode switching becomes smooth.

Furthermore, since the effectiveness of regenerative braking can be adjusted by the accelerator opening, control of the motor speed becomes easy.

[Brief description of drawings]

FIG. 1 is an overall side view of a motorcycle according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a circuit diagram showing a control system of a motor.

FIG. 4 is a vertical sectional view of an accelerator grip portion showing a structure of an accelerator opening sensor.

5 is a sectional view taken along line VV of FIG.

6 is a cross-sectional view taken along the line VI-VI of FIG.

7 is a view taken along line VII-VII of FIG.

8 is a sectional view taken along line VIII-VIII of FIG.

9 is a sectional view taken along line IX-IX in FIG.

FIG. 10 is a partially enlarged view of FIG.

FIG. 11 is a schematic diagram showing a mode discrimination table in the present embodiment.

FIG. 12 is a schematic diagram showing a drive duty ratio table in the present embodiment.

FIG. 13 is a schematic diagram showing a regenerative braking duty ratio table in the present embodiment.

FIG. 14 is a characteristic diagram showing a relationship between accelerator opening and power in the present embodiment.

FIG. 15 is a flowchart showing the operation of one embodiment of the present invention.

[Explanation of symbols]

10A ... Battery 11 ... controller 36U, 36V, 36W ... coil 41 ... accelerator grip 42 ... accelerator opening sensor 43 ... driver 44 a to 44 f ... FET 45 ... switching circuit 46 ... handle pipe 90 ... speed sensor D _a to D _f ... Diode M ... Motor Wr ... Rear wheel

Claims (2)

[Claims] 1. A rotation sensor for detecting the number of rotations of a motor,
An accelerator opening sensor, a discriminating means for discriminating between the regenerative braking mode and the drive mode based on the motor rotational speed and the accelerator opening, and on / off duty ratio information of the switching element of the inverter in the regenerative braking mode. Storage means stored corresponding to the number of revolutions and the accelerator opening,
When it is determined that the regenerative braking mode is determined by the determination means, the on / off duty ratio information corresponding to the motor rotation speed and the accelerator opening is retrieved from the storage means, and the on / off corresponding to the retrieved on / off duty ratio information. A regenerative braking device for an electric vehicle, comprising: a control unit that controls a switch element with a duty ratio to perform regenerative braking. 2. The regenerative braking device for an electric vehicle according to claim 1, wherein the vicinity of the motor driving force zero line is a boundary between the regenerative braking mode and the driving mode in the determining means.