Tri-objective LPV controller design for the thermal management of motor drive parameters in an electric vehicle

The increase in consumption of fossil fuels in transportation sector causes global warming and greenhouse gas emissions. Electric vehicles (EVs) provide an alternate solution to this combustion of fossil fuels. They use traction motor drives (mostly induction type) instead of combustion engines, but these drives suffer from parameter (stator, rotor resistance and mutual inductance) variations that result in the deterioration of drive as well as vehicular performance. The increase in the ambient and operating temperatures experienced by EV in its desired driving cycle is the major cause of such parameter variations. This paper proposes a tri-objective linear parameter varying (LPV) controller and observer design that allows these variations without affecting the performance of motor drive and vehicle. The controller design incorporates the linear matrix inequalities (LMIs) to guarantee the inherent system stability and L2 gain bound. The performance of LPV controller is compared with that of proportional-integral-derivative (PID) controller in case of motor drive and vehicular dynamics. The MATLABbased nonlinear simulations are carried out and the results are presented in terms of driveś terminal characteristics and highway fuel economy test (HWFET) drive cycle. These results ensure the excellent robust performance of the proposed control technique.