Method for controlling regenerative braking of vehicle
A method for controlling regenerative braking of a vehicle is provided, in which a driving area of a motor is decided when shifting gears during regenerative braking, and an amount of regenerative braking is determined based on the decided result. The method includes a first process of deciding whether motor torque is in a constant power mode, a second process of deciding whether the motor torque is in a constant torque mode, and a third process of deciding whether the mode of the motor torque is converted into the constant torque mode from the constant power mode.
1. A method for controlling regenerative braking of a vehicle, in which a driving area of a motor is decided when shifting gears in the vehicle during regenerative braking, and a regenerative braking amount is determined, based on the decided driving area of the motor,
wherein it is decided, in order to decide the driving area of the motor, whether a motor torque is in a constant power mode, whether the motor torque is in a constant torque mode, and whether a mode of the motor torque is converted into the constant torque mode from the constant power mode, and
wherein it is decided that the mode conversion of the motor torque occurs when the motor torque during gear shifting enters into the constant torque mode from the constant power mode, and in the mode conversion, the amount of regenerative braking is determined using a virtual motor torque value, which is fixed to the constant torque mode, and a gear ratio during gear shifting in the mode conversion.
2. The method of claim 1 , wherein, when the motor torque is in the constant power mode, the regenerative braking amount is determined using motor torque before torque intervention of a transmission control unit (TCU) and a gear ratio during gear shifting in the constant power mode.
3. The method of claim 1 , wherein, when the motor torque is in the constant power mode, the amount of regenerative braking is determined by REGEN AV _ StadyPower =T m _ BeforeInt *GR cal , and a gear ratio during gear shifting uses a value calculated by
GR
cal
=
ω
TmIn
ω
TmOut
,
wherein GR cal is the calculated gear ratio during gear shifting, ω TmIn is a transmission input speed, ω TmOut is a transmission output speed, REGEN AV _ StadyPower is the amount of regenerative braking in the constant power mode, and T m _ BeforeInt is motor torque before torque intervention.
4. The method of claim 1 , wherein, when the motor torque is in the constant power mode, the amount of regenerative braking is determined by REGEN AV _ StadyPower =T m _ BeforeInt *GR cal *Eff TM , and a gear ratio during gear shifting uses a value calculated by
GR
cal
=
ω
TmIn
ω
TmOut
,
wherein GR cal is the calculated gear ratio during gear shifting, ω TmIn is a transmission input speed, ω TmOut is a transmission output speed, REGEN AV _ StadyPower is the amount of regenerative braking in the constant power mode, T m _ BeforeInt is motor torque before torque intervention, and Eff TM is a transmission efficiency.
5. The method of claim 1 , wherein, when the motor torque is in the constant torque mode, the amount of regenerative braking is determined using the motor torque before torque intervention of a transmission control unit (TCU) and a gear ratio during gear shifting in the constant torque mode.
6. The method of claim 1 , wherein, when the motor torque is in the constant torque mode, the amount of regenerative braking is determined by REGEN AV _ StadyTorque =T m _ BeforeInt *GR cal , and a gear ratio during gear shifting uses a value calculated by
GR
c
al
=
GR
before
+
∫
T
=
0
T
shift
_
end
α
ⅆ
T
,
wherein GR cal is the gear ratio during gear shifting in the constant torque mode, GR before is a gear ratio before gear shifting, a is a gear ratio slope in the constant torque mode, REGEN AV _ StadyTorque is the amount of regenerative braking in the constant torque mode, T m _ BeforeInt is the motor torque before torque intervention, and T shift _ end is a shift end time.
7. The method of claim 1 , wherein, when the motor torque is in the constant torque mode, the regenerative braking amount is determined by REGEN AV _ StadyTorque =T m _ BeforeInt *GR cal *Eff TM , and a gear ratio during gear shifting uses a value calculated by
GR
c
al
=
GR
before
+
∫
T
=
0
T
shift
_
end
α
ⅆ
T
wherein GR cal is the calculated gear ratio during gear shifting, REGEN AV _ StadyPower is the amount of regenerative braking in the constant power mode, T m _ BeforeInt is motor torque before torque intervention, Eff TM is a transmission efficiency, GR before is a gear ratio before gear shifting, and a is a gear ratio slope in the constant torque mode.
8. The method of claim 6 , wherein the gear ratio slope in the constant torque mode is determined by
α
=
GR
diff
Δ
T
shift
,
and a differential gear ratio uses a value calculated by
GR diff =GR after −GR before ,
wherein GR after is a gear ratio after gear shifting, GR before is the gear ratio before gear shifting, and ΔT shift is a shift time.
9. The method of claim 1 , wherein, when the mode of the motor torque is converted into the constant torque mode from the constant power mode, the amount of regenerative braking is determined by REGEN AV _ ModeChange =T m _ Virtual *GR cal , and a gear ratio during gear shifting uses a value calculated by
GR
c
al
=
GR
before
+
∫
T
=
0
T
shift
_
end
γ
ⅆ
T
,
wherein REGEN Av _ ModeChange is the amount of regenerative braking in the mode conversion, T m _ Virtual is a virtual motor torque value, which is fixed to the constant torque mode, GR cal is the gear ratio during gear shifting in the mode conversion, GR before is a gear ratio before gear shifting, γ is a gear ratio slope in the mode conversion, and T shift _ end is a shift end time.
10. The method of claim 1 , wherein, when the mode of the motor torque is converted into the constant torque mode from the constant power mode, the amount of regenerative braking is determined by REGEN AV _ ModeChange =T m _ Virtual *GR cal *Eff TM , and a gear ratio during gear shifting uses a value calculated by
GR
c
al
=
GR
before
+
∫
T
=
0
T
shift
_
end
γ
ⅆ
T
,
wherein REGEN AV _ ModeChange is the amount of regenerative braking in the mode conversion, T m _ Virtual is a virtual motor torque value which is fixed to the constant torque mode, GR cal is the gear ratio during gear shifting in the mode conversion, Eff TM is a transmission efficiency, GR before is a gear ratio before gear shifting, γ is a gear ratio slope in the mode conversion, and T shift _ end is a shift end time.
11. The method of claim 9 , wherein a gear ratio slope (α) in the constant torque mode is used as the gear ratio slope (γ) in the mode conversion, and the gear ratio slope (α) is calculated by
α
=
GR
diff
Δ
T
shift
,
wherein GR diff is a differential gear ratio between before and after gear shifting, and ΔT shift is a shift time.