Mixed-Integer Optimal Control for Switching Powertrain System With Dwell-Time Constraints

The optimization of powertrain systems presents a challenging problem due to complex external disturbances and the computational demand arising from mixed-integer control variables. Moreover, the dwell-time constraint (DTC) of integer variables is essential to prevent frequent switching, a factor not addressed in most existing research. This brief proposes a tailored real-time control method for mixed-integer optimal problems, incorporating DTCs and time-varying external input. By decoupling the solving process of the integer variable and continuous variable, the algorithm is divided into three parts, in which the DTC is considered, aiding the controller in avoiding frequent shifting of integer variables with a negligible impact on the economics. A demonstrative simulation of the powertrain system is developed to validate the effectiveness of the proposed algorithm in terms of both control performances and computational load under the Speedgoat hardware system.