Efficiency and performance analysis of DTC-based IM drivetrain using variable dc-link voltage for electric vehicle applications

摘要

In recent times, there has been a surge in R&D activities in the area of electric vehicles (EVs). This surge is fuelled by various governmental policies that aim at increasing the penetration of EVs on roads. This work aims at developing and analyzing drivetrain configurations for city commute vehicles. Since city commute involves frequent start stops, it is necessary to focus on the dynamic performance as well as the system efficiency. Here two drivetrain configurations are considered. The first has a battery pack, an inverter, and an induction motor while the second configuration has an additional dc-dc converter. A detailed control strategy for each drivetrain is presented. Moreover, an experimental setup is developed that mimics the behavior of a scaled-down vehicle. Both the configurations are subjected to extensive experimentation using the developed setup and it is found that despite the use of an additional dc-dc converter, the second configuration has better overall system efficiency in city driving conditions. To explain the results, detailed efficiency maps of the individual subsystem and the overall system are also presented. Furthermore, the drive cycle response and energy consumption analysis, for both the drivetrains for NYCC and city part-NEDC are presented.