Power Management Strategy Based on Vehicle Dynamics for the Performance Improvement of Electric Vehicles

Abstract

The performance of an Electric Vehicle can be improved by using a power management strategy based on vehicle dynamics. The dynamic behaviour of the vehicle is analysed using drive cycles (DC). The frequent occurrence of traffic lights in the city requires increased starting and stopping of the vehicle and hence performance of vehicle is affected along with battery life. The Ultra capacitor(UC) used with the battery can be controlled to ensure lesser stress on battery. The proposed fuzzy logic controller operates the system to allow the UC to solely supply the power requirement during frequent velocity changes and supports the battery during normal running conditions. The methodology considers the power demand and the vehicle velocity to generate the control action on the dc-dc converters. The performance of the vehicle with the controller is evaluated using simulation experiments in Matlab/Simulink. The experiment used a modified drive cycle based on a case study in Trivandrum city. The control strategy ensures energy savings and also reduces the size of the battery pack. The proposed strategy is compared with frequency sharing based algorithm and it is found to yield an energy savings of 4.38%.