Seite - 239 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2016,9, 410 Table4.Performancecomparisonswithotherpublishedconverters. Items Topology ThisWork [17] [22] [23] Switchingcontrol structure two-phase single-phase single-phase single-phase Outputripple Low High Medium Medium Step-upconversionratio 4/(1´Db) n/(1´Db) 2/(1´Db) 1/(1´Db)2 Step-downconversionratio Dd/4 Dd/(1+n´nDd) Dd/2 (Dd)2 High-sidevoltage 385V 400V 200V 62.5V Low-sidevoltage 48V 48V 24V 10V Realizedprototypepowerrating 500W 200W 200W 100W Numberofmainswitches 8 4 4 4 Numberofstoragecomponents 7 5 5 5 Maximumefficiency(chargestate) 96% 91.6% 94.8% 91.5% Maximumefficiency(dischargestate) 95% 94.3% 94.1% 92.5% n: the turnsratioofcoupled inductor [17]. Load Source Scope Converter Controller Power Meter Figure23.Photographof therealizedBDCprototypeandthe testbenchsystem. 5.Conclusions Anovel BDC topologywith high voltage conversion ratio is developed and a 500W rating prototype systemwith 48Vbattery input is constructed. Applying thedevelopedBDC topology to the48Vmini-hybridpowertrainsystemisalsoexpected in the future [27]. In this study, thanks to theULClocatedat the low-sidestage,highpowerdensityandefficiency inall loadrangemake thestudiedBDCapromisingtwo-stagepowerarchitecture. Furthermore, the IBCPClocatedat the high-side stagecanachieveamuchhighervoltageconversion ratioundera reasonabledutycycle. Insummary, theproposednovelBDCoffers the following improvements: (1)highvoltageconversion ratio; (2) lowripplecurrent; (3) it is simpler todesign, implementandcontrol. Finally,a500Wrating low-powerprototypesystemisgivenasanexampleforverifyingthevalidityoftheoperationprinciple. Experimental results show that ahighest efficiencyof 96%and95%canbeachieved, respectively, in chargeanddischarge states. Certainly, bymakinga suitableprintedcircuit board (PCB) layout, andwithgoodcomponentplacementandgoodheatdissipationtransferprocess, thenovelBDCcan be implementedforhigherpowerconversionapplications. Acknowledgments:ThisresearchissponsoredbytheMinistryofScienceandTechnology,Taiwan,undercontracts 104-2221-E-027-125, 104-2623-E-027-005-ET, and104-2622-E-027-023-CC3. Theauthorwould like to thank the student, Jie-TingLi for forhishelp in theexperimentandDr.Yuan-ChihLinforhissuggestions. Conflictsof Interest:Theauthordeclaresnoconflictof interest. References 1. Lai,C.M.; Pan,C.T.; Cheng,M.C.High-efficiencymodularhigh step-up interleavedboost converter for dc-microgridapplications. IEEETrans. Ind.Appl. 2012,48, 161–171. [CrossRef] 2. Boroyevich,D.;Cvetkovic, I.;Burgos,R.;Dong,D. Intergrid:Afutureelectronicenergynetwork? IEEEJ. Emerg. Sel. Top. PowerElectron. 2013,1, 127–138. [CrossRef] 239