optimization of multiple transmission layouts for minimal energy consumption of a battery electric vehicle

Battery electric vehicles (bevs) are a promising solution for reducing the impacts of passenger vehicles on the environment. however, their driving range is restricted due to the limitations of battery technologies. this range can be extended by adoption of multiplespeed transmissions. most of the comparisons in the related studies are based on nonoptimal designs or limited to modal driving cycles. furthermore, the impact of powersplit continuously variable transmission (pscvt) layout with type iii power flow on the power consumption of bevs has never been examined. in this paper, single, two and threespeed transmissions along with pscvts with type i and iii power flows are optimized for a case study bev. furthermore, the effect of push belt and fulltoroidal cvts in construction of pscvt are compared. the results demonstrate that a pscvt with type i power flow equipped with the fulltoroidal cvt has the best performance. however, it reduces the energy consumption by 0.36% compared to the optimal twospeed layout. in addition, its ratio range is more limited which can negatively impact the dynamic performance. finally, simulation of the optimal designs along a different cycle proves that the obtained results are consistent, regardless of the driving cycle.