Optimal powertrain design and control of a 2-IWD electric race car

In this work, the optimal powertrain design and control problem of a 2-independent-wheel-driving (2-IWD) electric race car aiming at minimizing the lap time on a given track is formulated and solved with a developed optimal control software GDYNOPT, which is based on the direct transcription method and nonlinear programming (NLP). There are three innovative features of this work with respect to the state of the art literature. The first original contribution is that both the static design parameters of the powertrain and time variant control parameters are selected as the parameters to be optimized in the formulated problem. The second one is that a nonlinear load transfer model considering the aerodynamics is derived and taken into account in the formulated problem. The last one is that the dependence of the mass of the powertrain on the design parameters is considered and described with the derived mass model of the motors and gearboxes. The formulated optimal design and control problem with a 7 degrees of freedom (7-DOF) vehicle model considering the nonlinear load transfer moving in a curvilinear coordinated system is solved. The obtained results of the optimal design and control are presented in the last section of this paper.