Power Management Strategy for an Electric Vehicle Driven by Hybrid Energy Storage System

Abstract

The selection, sizing, and management of energy storage system for an electric vehicle (EV) are critical while considering later's large-scale deployment. The complementary nature of battery and ultracapacitor (UC) makes the combination a suitable hybrid energy storage system (HESS) for EV since the peak to average power demand ratio is very high especially for an urban drive commonly characterized by frequent acceleration and deceleration. A suitably sized UC combined with the battery pack provides necessary high power density as well as high energy density. The HESS makes the EV more effective with improved dynamic response, higher kilometers per charge, and longer battery life. This paper presents a fuzzy logic control based power management strategy to employ UC to relieve the battery of peak discharge currents as well as rapid charging currents. The power conditioning unit limits the battery current as well as its rate of change by maintaining the UC state of charge in the desired limits. The paper presents some of the key simulation and experimental results for a prototype EV system tested for various modes of operations.

KEYWORDS:

• Electric vehicle
• Induction motor
• LFP battery
• Multi-input bidirectional converter
• Power flow
• Three phase inverter
• Ultracapacitor

Additional information

Funding

We sincerely express our gratitude to The Institution of Engineers (India) for partially funding the project.

Notes on contributors

R. Bindu

R Bindu is currently working as an associate professor in Fr C Rodrigues Institute ofTechnology, Navi Mumbai and is pursuing PhD from the University of Mumbai. She has completed her BTech in electrical and electronics engineering from the University of Kerala in 1990 and MTech in electrical engineering (Energetics) from REC (now NIT), Calicut in 1992. Her field of interest includes electrical drives and control and power management in electric vehicles. She is a member of the IEEE and Institution of Engineers (India).

Sushil Thale

Sushil Thale received the BE and ME degrees in electrical engineering from the University of Mumbai, Mumbai, India, in 1992 and 1996, respectively. and the PhD degree from Department of Electrical Engineering, Indian Institute of Technology, Bombay (IIT-B), India, with a specialization in power electronics and power systems. Since 1995, he has been a member of the Faculty of the Department of Electrical Engineering, Fr C Rodrigues Institute of Technology, Navi Mumbai, India. Currently, he is working as professor. His areas of interest include renewable energy systems, microgrids, and electrical vehicles. Prof Thale is a Fellow of the Institution of Electronics and Telecommunication Engineers (IETE) and a senior member of IEEE. Email: [email protected]