All Wheel Control for Electric Drive Vehicles - Outlander PHEV S-AWC - - PowerPoint PPT Presentation

May, 2019

All Wheel Control for Electric Drive Vehicles

• Outlander PHEV S-AWC -

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MITSUBISHI MOTORS

EV/Powertrain Engineering Development Div.

Kaoru SAWASE, Ph.D. & Tomo KATO

All Wheel Control History

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1987 2013 2019 2007 2010

6th Galant VR-4 (1987) [4WD/4WS/ABS] Outlander PHEV (2013) Lancer Evolution X(2007) Outlander (2010) Eclipse Cross (2017) Technology Development Concept Integrated Vehicle Dynamics Control System 2nd Pajero (1991) [SS4]

1996

8th Galant VR-4 (1996) [AYC/ASC] Grandis (2003) [EC-4WD]

1990 2003

Lancer Evolution VII (2001) [ACD] Diamante (1990) [TCL] 3rd Pajero (1999) [SS4-Ⅱ]

1999

AWC : Technology Development Concept

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 To provide “Driving pleasure”and “Toughness & Safety” by making the best use of four tire friction forces (since 1987)

lateral G acceleration G deceleration G

tire friction circle center of gravity longitudinal G lateral G

longitudinal force side force

four wheel model G bowl

S-AWC : Integrated Vehicle Dynamics Control System

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Lateral Torque Vectoring AYC 4WD ABS

＆

ASC

Integrated Vehicle Dynamics Control System

Longitudinal Torque Distribution 4-wheel Brake Control

lateral G acceleration G deceleration G effective Area lateral G acceleration G deceleration G lateral G acceleration G deceleration G effective area effective area

Longitudinal Torque Distribution

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Device Differential Gear Clutch E-Motor

System Configuration Torque Distribution Characteristics

engine T/M engine T/M

clutch

M

differential gear

M

E-motor E-motor

front wheel torque rear wheel torque limit by clutch torque < In case of FWD vehicle base > during only FW speed > RW speed flexible distribution fixed distribution by design phase

 3 kinds of device with different characteristics

front wheel torque front wheel torque rear wheel torque rear wheel torque

Target Dynamic Performance of S-AWC

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 “Confident Driving” as a vehicle behavior is faithful to the driver’s input, namely accelerator, steering, and brake, under any driving condition.

traction performance 1 2 3 4 5 1 2 3 4 5 handling & stability performance Ideal target

OUTLANDER PHEV (S-AWC) ECLIPSE CROSS (S-AWC) PAJERO SPORT ICE FR 4WD Electrified 4WD ICE FF 4WD Japanese Vehicle B European Vehicle C Japanese Vehicle A European Vehicle D

Confident Driving

Control Policy of S-AWC

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lateral G acceleration G deceleration G control for cornering control for stability control for traction

 Smooth and seamless control provides predictable vehicle behavior

control for traction control for cornering control for stability

mixing at anytime 4WD AYC ABS&ASC 4WD AYC ABS&ASC switching by situation

Usual Control

vehicle behavior

control for traction control for cornering control for stability

lateral G acceleration G deceleration G control for cornering control for stability control for traction vehicle behavior

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lateral G steer angle / base steer angle 1

snow road w/o S-AWC small difference from dry paved road characteristics predictable cornering limit

30R

cornering characteristics test

drive to course

mild acceleration

stability factor : A

Control Policy of S-AWC

 To realize robust vehicle behavior for various driving conditions

snow road w/ S-AWC dry paved road w/o S-AWC dry paved road w/ S-AWC

Lancer Evolution X S-AWC

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 The All Weather Sport Sedan, the first application of S-AWC （2007-2015） Longitudinal Torque Distribution ： ACD Lateral Torque Vectoring ： AYC Differential + Brake AYC 4-wheel Brake Control ： ABS & ASC

Outlander PHEV S-AWC

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Twin Motor 4WD

ABS/ASC unit

Brake AYC Yaw Moment

PHEV ECU

(S-AWC Controller)

 Plugin Hybrid EV equipped with state-of-the-art S-AWC（2013-） Longitudinal Torque Distribution ： Twin Motor 4WD Lateral Torque Vectoring ： Brake AYC 4-wheel Brake Control ： ABS & ASC

Advantage of Twin Motor 4WD

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ideal control of longitudinal torque distribution high flexibility of torque control responses highly efficient 4WD system

０ time driving torque

response characteristics

 3 Advantages

Control Diagram of Twin Motor 4WD

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Total drive torque T

＋

Basic Distribution Control

＋

Target Slip Difference Control Yaw Rate Feedback Control

TDNFB TYRFB TF0 TR0

＋ ＋ ＋ － TFB

Front drive torque TF Feedback Control

 Basic Distribution Control to realize Ideal Longitudinal Torque Distribution

Basic Distribution Control Rear drive torque TR

Ideal Longitudinal Torque Distribution

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 Led from 4-wheel model

GX :Longitudinal G GYmax :Maximum Lateral G GYfmax , GYrmax :Maximum Front / Rear Lateral G Tf , Tr :Front / Rear Distribution Torque Tvf , Tvr :Front / Rear Vectoring Torque Mf , Mr :Yaw Moment Generated by Front / Rear Torque Vectoring Ri :Tire Friction Force of i Di :Driving Force of i Cmi :Maximum Cornering Force of i i = fl, fr, rl, rr :Wheel Position (Front Left, Front Right, Rear Left, Rear Right) mf , mr :Front / Rear Vehicle Mass L :Wheel Base Hg :Height of Center of Gravity Wf , Wr :Front / Rear Track Kf , Kr :Front / Rear Vehicle Roll Stiffness Hf , Hr :Height of Front / Rear Roll Center Hs :Distance between Center of Gravity and Roll Axis Tire Friction Circle Ri : Radius

GX Tvf Tvr GYmax GYfmax GYrmax Cmi Di Mg = Mf + Mr Engine Tf Tr

Ideal Longitudinal Torque Distribution

14 Front Wheel Torque[Nm] Rear Wheel Torque[Nm]

GY

( μ = 1.0 )

 Analysis result on μ = 1.0

Ideal Longitudinal Torque Distribution

15 Front Wheel Torque[Nm] Rear Wheel Torque[Nm]

GY

( μ = 0.7 )

 Analysis result on μ = 0.7

Ideal Longitudinal Torque Distribution

16 Front Wheel Torque[Nm] Rear Wheel Torque[Nm]

GY

( μ = 0.4 )

 Analysis result on μ = 0.4

Ideal Longitudinal Torque Distribution

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Front Wheel Torque[Nm] Rear Wheel Torque[Nm]

GY = 0.6G GY = 0G GY = 0.2G GY = 0.4G

a b

 Ideal distribution is achieved from GX and GY as kF kF = a / ( a + b)

Basic Distribution Control

Total Drive Torque Longitudinal Acceleration Lateral Acceleration Front Wheel Basic Distribution Ratio

Effect of Ideal Longitudinal Torque Distribution

 Achieve smooth vehicle behavior

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Road : Packed snow Steering : Fix Accelerator : 50% Front wheel drive base cont. Rear wheel drive base cont. Ideal Distribution cont.

Conclusion

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• Technology development concept AWC was described.
• Integrated vehicle dynamics control system S-AWC was defined, and its

target performance, control policy and the configuration of each vehicles were described.

• The ideal longitudinal torque distribution, the method to realize it in Twin

Motor 4WD, and its effect were described.

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