Creeping Control Strategy for Direct Shift Gearbox Based on the Investigation of Temperature Variation of the Wet Clutch
Proposing an appropriate control strategy is an effective and practical way to address the overheat problems of the wet multi-plate clutch in Direct Shift Gearbox under the long-time creeping condition. To do so, the temperature variation of the wet multi-plate clutch is investigated firstly by establishing a thermal resistance model for the gearbox cooling system. To calculate the generated heat flux and predict the clutch temperature precisely, the friction torque model is optimized by introducing an improved friction coefficient, which is related to the pressure, the relative speed and the temperature. After that, the heat transfer model and the reasonable friction torque model are employed by the vehicle powertrain model to construct a comprehensive co-simulation model for the Direct Shift Gearbox (DSG) vehicle. A creeping control strategy is then proposed and, to evaluate the vehicle performance, the safety temperature (250 ℃) is particularly adopted as an important metric. During the creeping process, the temperature of two clutches is always under the safety value (250 ℃), which demonstrates the effectiveness of the proposed control strategy in avoiding the thermal failures of clutches.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.2643921Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 599
 P. Walker, B. Zhu, N. Zhang, “Powertrain dynamics and control of a two speed dual clutch transmission for electric vehicles,” Mech. Syst. Sig. Process. Vol. 85 pp. 1-15, 2017.
 M. Kulkarni, T. Shim, Y. Zhang, “Shift dynamics and control of dual-clutch transmissions,” Mech. Mach. Theory, vol. 42(2) pp. 168-182, 2007.
 J. Liu, B. Ma, H. Li, M. Chen, G. Li, “Control strategy optimization for a dual-clutch transmission downshift with a single slipping clutch during the torque phase,” J. Proc. Inst. Mech. Eng. Part D-J. Automob. Eng. Vol, 232(5), pp. 651-666, 2017.
 M. Goetz, M.C. Levesle, D.A. Crolla, “Dynamics and control of gearshifts on twin-clutch transmissions,” J. Proc. Inst. Mech. Eng. Part D-J. Automob. Eng. Vol, 219(8) pp. 951-963, 2005.
 G. Xuexun, F. Chang, C. Fei, Y. Jun, Y. Zhang, “Modeling and simulation research of dual clutch transmission based on fuzzy control,” SAE Technical Paper, 2007.
 Z.G. Zhao, H.J. Chen, Z.X. Zhen, Y.Y. Yang, “Optimal torque coordinating control of the launching with twin clutches simultaneously involved for dry dual-clutch transmission,” Veh. Syst. Dyn. Vol, 52(6) pp. 776-801, 2014.
 J.P. Holman, “Heat transfer,” New York: McGraw-hill, 1986, pp.521-565.