Photovoltaic energy based fast charging strategy for VRLA batteries in small electric vehicles for sustainable development

The use of electrical vehicles is increasing day by day to favor sustainability and mitigate energy crisis and provide an eco-friendly environment for the society. Transport in rural areas mainly depends on battery operated three wheeled vehicles (BoTV). Such vehicles are most reliable source of conveyance in rural India, especially in rural Bengal, mainly due to their lower road space requirement, easy navigation through narrow roads. Convenience of movement on any type of road with door-to-door transport. However, the charging of the batteries used in a BoTV system is becoming an alarming issue these days. Lead acid batteries are used in BoTV system because of its lower cost, but the main drawback is its longer charging period. To address such issues, the authors have proposed a modified fast charging topology in this paper. A solar powered asymmetrical half bridge rectifier with DC-DC energy recovery cell has been designed to minimize the charging time. Besides that, frequent shut down of electricity is the major problem of rural Bengal which hampers the battery charging as well as reduces the daily income of the BoTV operator. By using PV based fast charging techniques this problem can be solved leading to better sustainability. Zero-voltage switching (ZVS) technique is implemented in asymmetrical half bridge (AHB) to increase the charger power density to enhance the quality of charging. ZVS technology of AHB with energy recovery cell makes the charging method faster. According to the analysis and the results, it has been found that the overall charging time of the battery has been reduced by around 2.5 h per day and the savings of a BoTV operator has increased by at least (sic)2350 ($28.23) per month.