Improved Design of a Battery Charger for Three-Wheeler Auto Rickshaws in Bangladesh with Low Harmonic SWISS Rectifier

Three-wheeler auto-rickshaws are very popular in the developing Asian countries like Bangladesh and India due to less human effort and reduced fuel cost. These auto-rickshaws require their batteries to be charged in frequent interval and they are normally charged at night in the garage. A huge number of auto-rickshaws are being charged every day. The commercial charging system used for these vehicles are mostly step-down transformer based which are less efficient due to low power factor and inducing harmonics to the system. AC-DC conversion injects remarkable harmonics to the utility grid. Importers import low efficient chargers since there is no standard regulation prescribed by the country. In a country like Bangladesh, these harmonics and power losses are unexpected where power shortage is a crucial issue. But if proper charging infrastructure is selected, power loss would be minimized and efficiency would increase. This paper proposes an improved model for charging system with high efficiency and lower harmonics implementing SWISS rectifier which uses two-switch buck power factor correction (PFC) topology. Both slow and fast charging scheme have been implemented for the proposed model and a comparative study has been made at the end of this paper. The simulation was performed in MATLAB SIMULINK version r2018a.