This focuses on the cooperative control of the drive motor and clutches for the gear shift of a parallel hybrid electric vehicle (HEV) with dual-clutch transmission (DCT). To achieve outstanding gear shift performance, a HEV with DCT powertrain requires sophisticated control of two clutch actuators and power sources. To improve shift quality, a new shift control strategy based on feedback of both speed and torque states is implemented in this slide.

1. Cooperative Control Of Drive MotorAnd
Clutch For Gear Shift Of Hybrid Electric
Vehicles With Dual-clutch Transmission
PRESENTED BY
MOHAMMED SAHAD

2. CONTENTS
1. LITERATURE REVIEW
2. INTRODUCTION
3. DRIVELINE MODELING AND TORQUE ESTIMATION
4. CONTROL STRATEGY DEVELOPMENT
5. CONCLUSION
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3. Author/Year Journal paper
Sooyoung Kim
Seibum B. Choi
(2022)
Cooperative Control of Drive Motor and Clutch for Gear Shift of Hybrid Electric
Vehicles with Dual-clutch Transmission
Pierluigi Pisu
Giorgio Rizzoni
(2007)
A Comparative Study Of Supervisory Control Strategies for Hybrid Electric Vehicles
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4. Hybrid Electric Vehicle (HEV)
• A HEV is EV with second source of power as the alternative power unit (APU).
• A HEV can achieve the cruising range and performance advantages of conventional vehicles
• Consume less fuel than conventional engine-driven vehicles.
• HEVs provide lower emissions than conventional engine-driven vehicles by effectively using
dual energy sources (a fuel and electrical energy).
• The APU is used as a second source of energy, to overcoming some of the problems of pure
electric vehicles.
INTRODUCTION
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DEPT. OF MECHANICAL ENGG. IETCU

5. 4
• Two types of hybrid vehicle configurations
• Parallel Hybrids
• Series Hybrids
• Study deals gear shift control of parallel HEV equipped
with dry dual-clutch transmission (DCT)
• Main objective is minimize fuel consumption
Configuration of a parallel HEV

6. 5
• Managing power distribution between two sources and identifying optimal gear ratio in any driving
situations are critical for improving HEV performance.
• Since there is no smoothing effect of torque converters, DCT are likely to cause an awkward shift shock
during gear shifting, especially when shifting is performed quickly .
• Fast gear shifting is generally required to achieve good fuel economy
• And minimize vehicle acceleration losses .

7. 6
• Smooth and fast shifting conditions are generally regarded as two main goals of shift control .
• Smooth and fast shifting conditions are in conflict with each other
• In this work, an output shaft torque based shift control strategy is proposed to improve the gear shift
performance .
• The output shaft torque and the slip speed of the on-coming clutch are selected as the outputs
• And are controlled by three actuators: off-going clutch, on coming clutch, and the power source (drive
motor).

8. Driveline Model
• The HEV dealt with in this work has two additional electric
machines: an ISG and a drive motor.
• We only consider its parallel mode operations where engine clutch
is engaged ( vehicle is partially or fully driven by the engine).
• we define slip speed of on-coming clutch (clutch 2), torsion rate of
output shaft, output shaft torque as three states
Driveline model structure
DRIVELINE MODELING AND TORQUE ESTIMATION
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9. Driveline Model
Driveline model structure
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10. 9
• The dynamics of the HEV driveline operating in
parallel mode is described as

11. Torque Observer Design
• The lack of torque sensors in production cars, knowing the torque states of the driveline is crucial for precise
control
• It is one of the biggest challenges facing gear change management.
• linear state observer is developed to estimate the output shaft torque as
• The vehicle load torque estimated by combining net input torque multiplied by gear ratios and vehicle
inertia,
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12. Overview
• The control strategy is developed for the 1-2 upshift, which is difficult to control due to the large
amount of torque transmission
• A gear shift process of DCT usually discriminated as two phases:
• Torque Phase : Torque handover from the off-going clutch to the on-coming one occurs
• inertia phase : The on-coming clutch with a new gear ratio is synchronized with the power sources
• We consider End Phase additionally, which comes immediately after the inertia phase, for more
accurate driveline oscillation control
• In case of HEV, the drive motor can used for reducing driveline oscillations during the end phase
CONTROL STRATEGY DEVELOPMENT
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13. • To provide smooth and rapid shifting, the proposed control employs a dynamic torque observer to precisely
track the appropriate transient torque as well as the clutch slip speed during the inertia phase.
• Due to the sluggish dynamics of the engine, engine control is often employed only in gear shifts.
• In HEV, the quick dynamic properties of the drive motor allow for more effective transient torque control
through the vehicle driveline than engine control alone.
• A robust multivariable controller is designed for coordinated control of the drive motor and the approaching
clutch, particularly during the inertia period, which influences the overall shift quality.
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14. 13
Typical responses of vehicle with DCT during an upshift(1st to 2nd gear)
Control Strategy for Each Shifting Phase

15. Gear Shift ProcessAnalysis
• If the disengagement of the off-going clutch and the engagement of the on-coming clutch are optimally
controlled, output torque dip is unavoidable unless the power source torque is further increased.
• During the inertia phase, the speed or power of the power sources should be reduced to be synchronized with the
input shaft with a new gear ratio.
• In the HEVs, the regenerative operation of the drive motor can be used for the inertia torque compensation
• As the on-coming clutch is fully engaged with the drive motor, the end phase begins
• The lock-up of the on-coming clutch often accompanies driveline oscillations.
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16. 15
Torque Phase Control
• The intention of torque phase control is to free the off-going
clutch
• And engage the on-coming clutch at the right point to provide
optimal drivability.
• Open-loop control method is applied to avoid the negative
consequences of stick-slip vibrations generated by
insufficient feedback control.

17. 16
Inertia Phase Control
• In the inertia phase, cooperative control of the on-coming clutch and the power
sources is crucial.
• Multivariable feedback control of output torque and slip speed to ensure fast and
smooth shift.
• In HEVs, the usage of the drive motor may increase the whole control
performance.

18. • This paper proposed an integrated torque and speed control strategy for gear shift processes of a parallel-
type HEV with DCT.
• For the inertia phase, in particular, a robust multivariable controller based on H-infinity loop shaping was
designed to effectively control both clutch slip speed and output shaft torque.
• An adaptive torque observer was developed to concurrently monitor the transmitted torque of both clutches
and the output shaft in the driveline, which was used to improve the torque control performance of the
proposed controller.
CONCLUSION
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19. THANK YOU