Digital ZVS Full-Bridge Phase-Shift Converter For EV Charger

Electric vehicle has become a hot spot with the consideration about energy andenvironment. The focus of the industry is to design a charger to provide safe andeffective service for EV.This study is aimed to design and implement a10kW EV charger. To achievehigher power capability and conversion efficiency, a phase-shift full-bridge (PS-FB)ZVS DC/DC converter is adopted. The operation modes and design considerationssuch as duty loss,soft-switching,rectifying voltage spike and ringing effect areanalyzed. To be modular and integrated, this charger is controlled by a DSP which isresponsible for executing phase-shift control, secondary active clamping andself-tunning PI algorithm.Firstly, this paper introduces the development of EV charger and DC/DCconverter, including devices, soft-switching and control strategy as well as sometypical problems and improvements. Secondly, this paper analyzes the operationmodes and some key design considerations such as duty loss,soft-switching,rectifyingvoltage spike and ringing effect. Thirdly, this paper introduces the design of maincircuit including the calculations of parameters and the the type selection as well asthe driver,sample, protect circuit and power PCB. Fourthly, this paper introduces thedesign of control circuit including the selection of digital controller and humaninterface,and the phase-shift control,secondary active clamping and self-tunning PIalgorithm.Fifthly,this paper simulate the main circuit in PLECS to verify thecalculations and build a platform to test the performance of the converter. Finally, theconclusion and prospect is presented.This study designs and implements a digital DC/DC converter for EV charger. Anovel control strategy and algorithm is presented to achieve the ZVS and the ringingproblem is well solved. The platform built in this study can be used for furtherresearch.