Effect of Engine Start and Clutch Slip Losses on the Energy Management Problem of a Hybrid DCT Powertrain

A Dynamic Programming (DP) formulation is developed to find the global optimal solution to the energy management of a parallel Plug-in Hybrid Electric Vehicle (PHEV) equipped with a Dual-Clutch Transmission (DCT). The effects of integrating in the DP formulation the losses accounting for gearshifts and engine starts are studied in terms of the overall fuel consumption; the optimal control solutions obtained depends on the occurrence of these transient events. These sources of dissipation are modeled through physical considerations thus enabling the DP algorithm to decide when it is more convenient, in terms of minimizing the total energy consumption, to perform either a gearshift or an engine start. This capability differentiates the DP formulation here presented from those presented in previous studies.