Optimal energy management and shift scheduling control of a parallel plug-in hybrid electric vehicle

Online Synthesis of an Optimal Battery State-of-Charge Reference Trajectory for a Plug-in Hybrid Electric City Bus

“…The PHEV powertrain backward-looking model and the corresponding energy management control strategy are outlined based on the previous publications [9,18], respectively.…”

“…The engine torque τ e and the transmission gear ratio h are selected as control variables, which in combination with the driving cycle-defined wheel torque and speed variables τ w and ω w define the remaining powertrain variables (see Equations (1) and ( 2)). The control strategy is based on a combination of a rule-based (RB) controller and an equivalent consumption minimization strategy (ECMS) (see Figure 2 and [18]). The RB controller consists of an SoC controller and engine start-stop logic.…”

“…Exceptionally, the engine will be kept switched on regardless of the P * e signal if the M/G machine itself cannot deliver the demanded power P d due to its speed-dependent torque limit denoted in Figure 1d. The ECMS [18,20] provides an instantaneous minimization of the equivalent fuel consumption . m eq with respect to the control inputs τ e and h (2D-ECMS) [18]:…”

“…The ECMS [18,20] provides an instantaneous minimization of the equivalent fuel consumption . m eq with respect to the control inputs τ e and h (2D-ECMS) [18]:…”

“…Finally, the online synthesis method performs an SoC reference trajectory recalculation in each time step, to incorporate adaptive features with respect to memorized driving cycle characteristics from the trip start until the current time instant. The proposed methods are verified against the DP optimization benchmark, based on a PHEV-type city bus model and a previously developed PHEV control strategy comprising of an explicit SoC controller and an equivalent consumption minimization strategy (ECMS) [18]. In addition, a robustness analysis with respect to prediction errors of the road grade profile, mean velocity and mean demanded power is conducted.…”