Integrated Battery Charger with Delta Connected BLDC Motor for Electric Vehicle Applications

Abstract

Battery chargers and charging infrastructures are playing a vital role in the deployment of electric vehicles (EVs). Battery chargers must have advantages like high efficiency, more reliable, high power density, low cost, less volume, and weight. Four important factors are barriers in the development of EVs these are 1. battery life and high cost, 2. complexity of chargers, 3. lack of charging infrastructure and 4. chargers introducing harmonic to the utility grid. To reduce cost, weight, and size of on-board chargers, integrated battery chargers are proposed in kinds of literature. Integrated charger topology works with two modes of operation separately, propulsion (motoring) mode and charging mode. In this paper delta connected brushless direct current (BLDC) motor has been used for propulsion mode and same motor stator windings used as coupled inductances for charging mode of operation. In this paper hardware results with boost converter as a power factor correction circuit and MATLAB simulation results of two-channel interleaved boost converter (TCIBC) are presented. Total harmonic distortion (THD) for grid current with a single-channel boost converter (SCBC) 6.68% and simulation results with TCIBC 1.45% respectively. Also, mathematical modeling with delta connected motor is presented and a steady-state voltage gain equation has been derived with TCIBC.