Sungwha Hong

Shift control of a 2-speed dual clutch transmission for electric vehicle

This paper suggested a shift control algorithm for improving the shift quality(SQ) by modeling a dual clutch transmission(DCT)-type 2-speed transmission system for an electric vehicle(EV). In 2-speed transmission system, the driving comfort decreased when the driveshaft torque of the vehicle fluctuated by shifting gear, unlike with the existing single-gear ratio EV. To improve this, a shift control algorithm was proposed that controlled two units of shift actuators and a unit of a driving motor for the subject DCT. To evaluate the proposed shift control algorithm, a shift performance simulator based on MATLAB/Simulink that consisted of a motor, DCT, actuator, and vehicle model was developed by modeling a DCT-type EV with 2-speed transmission system. The SQ improvement was verified by reducing the overshoot torque of the driveshaft during inertia phase.

Simultaneous optical model analyses of elastic scattering, breakup, and fusion cross-section data for the He-6 + Bi-209 system at near Coulomb barrier energies

Based on an approach recently proposed by us, simultaneous

Mode shift control for a dual-mode power-split-type hybrid electric vehicle:

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Shift control of a dry-type two-speed dual-clutch transmission for an electric vehicle:

-analyses are performed for elastic scattering, direct reaction (DR) and fusion cross sections data for the

Development of a gear fork control algorithm to improve the shift quality of a dual-clutch transmission

^{6}

Extended optical model analyses of elastic scattering and fusion cross sections for the {sup 6}Li+{sup 208}Pb system at near-Coulomb-barrier energies using a folding potential

He+

Extended optical model analyses of elastic scattering, direct reaction, and fusion cross sections for the {sup 9}Be+{sup 208}Pb system at near-Coulomb-barrier energies

^{209}

Extended optical model analyses of elastic scattering and fusion cross section data for the {sup 12}C+{sup 208}Pb system at near-Coulomb-barrier energies by using a folding potential

Bi system at near-Coulomb-barrier energies to determine the parameters of the polarization potential consisting of DR and fusion parts. We show that the data are well reproduced by the resultant potential, which also satisfies the proper dispersion relation. A discussion is given of the nature of the threshold anomaly seen in the potential.

Development of a pressure control algorithm without a pressure sensor for a four-wheel drive unit:

This paper presents a mode shift control algorithm for reducing the variation in the driveshaft torque for a dual-mode power-split-type hybrid electric vehicle. To evaluate the shift characteristics of this hybrid electric vehicle, dynamic models for the hybrid electric vehicle powertrain were developed. Using the dynamic models, a mode shift performance simulator was developed, and simulations were performed. To analyse the shift characteristics during the mode shift, bond-graph models for the transient state were constructed, and state equations were derived. From the bond-graph models and state equations, it was found that the transient torque occurs because of the inertia torques of the first motor–generator and the second motor–generator. Based on the transient torque, a mode shift control algorithm was proposed, which compensates for the transient torque. To evaluate the performance of the proposed control algorithm, a test bench for the dual-mode power-split-type hybrid electric vehicle was developed. From the simulations and test results, it was found that the variation in the driveshaft torque was reduced by the proposed control algorithm, which provides improved shift quality.

Motor-generator control to improve shift quality for a dual mode power split transmission

In this paper, a shift control algorithm to improve the shift quality was proposed for an electric vehicle with a dry-type two-speed dual-clutch transmission. To analyse the shift characteristics of the target electric vehicle, dynamic models for the two-speed dual-clutch transmission and the drivetrain were developed. Based on the dynamic models, dynamic equations for the transient shift states were derived, and a shift performance simulator was constructed. From analysis of the transient shift state, it was found that the fluctuations in the driveshaft torque, which cause the shift quality to deteriorate, occurred as a result of the inertia torque. Based on the analytical results, a control algorithm was proposed using traction motor torque control as well as shift actuator stroke control. For traction motor control, a compensation torque was applied during the inertia phase. In that phase, actuator stroke control was performed by considering the torque margin and the kissing point during the torque phase instead of the existing map-based control. To evaluate the performance of the proposed control algorithm, a test bench for the target electric vehicle was developed. From the experimental results, it was found that the variations in the driveshaft torque and in the jerk were reduced by the proposed control algorithm, which thereby provides an improved shift quality.