Design and Control of a Novel Grid-tied Fast Charging Architecture for EV using PFC Interleaved Boost Converter
Subhabrata Pal, Avik Bhattacharya
Abstract
In this paper, a novel fast charging architecture is developed where Interleaved Boost Converter (IBC) functions as power factor correction (PFC) and Dual Active Bridge (DAB) DC-DC converter works as the main component for power transfer between the output of IBC and the EV battery. Here IBC operated in dual control loop. The outer loop maintains the desired DC-link voltage and inner current loop ensures unity power factor operation between grid voltage and grid current. To ensure faster operation of inner current loop, it is operated by PR controller whereas the outer loop employs PI controller for stable dynamic operation. PR controller ensures quicker elimination of steady state error; thus it reduces current tracking error faster than PI controller. Dual Active Bridge (DAB) converter is the most preferred DC-DC converter due to presence of its several advantages like: galvanic isolation, high power density, Bidirectional power flow capability, innate soft switching for maintaining the fast charging application. A well maintained closed loop control is designed for integrating the DAB with the main grid via PFC Interleaved Boost converter. With a constant voltage application, the DAB operates in a closed loop under variable load conditions. For variable load the THD of the grid current adheres the prescribed IEEE standard (IEEE-519). Here load is assumed to be resistive load. The overall system is verified by MATLAB/Simulink and thus it proves efficacy of the proposed fast charging architecture.