Int ern at i onal  Journ al of  P ower E le ctr on i cs a n d  Drive  S ystem   (I J PE D S )   Vo l.   11 ,  No.   4 ,  Decem be r 202 0 , p p.   18 44 ~ 1 856   IS S N:  20 88 - 8694 ,  DOI: 10 .11 591/ ij peds . v11.i 4 . pp18 4 4 - 1 856       1844       Journ al h om e page :  http: // ij pe ds .i aescore.c om   An   im pr oved   zero - vo lt ag e   zero - curr ent   t ransitio n   boost   convert er   employi ng   L - C - S   reson ant   netwo rk       Anand h   N. 1 ,   Ak hil esh   Sh ar ma 2 ,   Ju li us   Fu sic   S. 3 ,   R ames h   H. 4   1   Depa rtment   of   El e ct ri ca l   and   E l ec tron ic s   Eng ineeri ng,   Manip al   I nstit ute   of   Techn ology,   Man ipa l   Aca dem y   of   Hig her ,  India   2   Depa rtment   of   El e ct ri ca l   Eng in ee ring ,   North   E a stern   Reg iona l   I nstit ute   of   Sc ie n ce   and   Technol o gy ,  Indi a   3,4   Depa rtment   of   Mec ha tronics   E ngine er ing,   Thia gar ajar   Col le g e   of   Engi n ee rin g,   I ndia       Art ic le   In f o     ABSTR A CT   Art ic le   hist o ry:   Re cei ved   Dec   6 ,   201 9   Re vised   M a r   18 ,   20 20   Accepte d   M a y   19 ,   20 20       An   im prove d   ze ro - vol ta g e   ze ro - cur ren t   tra nsit ion   b oost   conve rt er   (IZ VZCTBC)   is   int rodu ce d .   Th i s   conve rt er   is   b asic a ll y   a   four th - orde r   DC - DC   conve rte r   w her ei n   a   L - C - S   ( Induc tor – Cap ac i tor – Sw it ch)   reso nant   c irc ui t   is   em b edde d   for   soft - sw it chi ng .   L - C - S   ta nk   ne twork   is   th e   modi f ie d   v ersion   of   conve n ti on al   ZVZCT   sw itch   ce l l.   The   m ai n   f ea tur e   of   L - C - S   ta nk   ci r cui t   is   to   enh anc e   th e   p erf orm anc e   of   z ero - voltage   z ero - cur ren t   tra ns it ion   boost   conve r t er   in   te r ms   of   el i mi na ting   the   high   cur ren t   stress,   d ec r ea sing   th e   sw it chi ng   losses   and   inc r ea sing   the   eff i ci en cy   of   converte r .   This   conve rt er   exhi bit s   both   z ero - voltage   turn   on   and   ze ro - c urr ent   turn   off   sw it chi ng   cha ra cteri sti cs   b ase d   on   the   g at i ng   signa ls   appl i ed   to   sw it che s .   The   prin ci pl e   of   oper at ion   and   time   dom ai n   ex pre ss ions   of   I Z VZCT   boost   co nver te r   with   L - C - S   c el l   ar e   p rese nte d .   For   th e   cl osed   loop   op era t ion,   digital   c ontrol ler   is   designe d   and   th e   p erf orm anc e   of   th e   cont ro ll er   has   be en   validated   t hroug h   simul ation   for   diffe ren t   l ine   a nd   loa d   var i at i ons.   The   m at he ma tica l   and   the ore ti c al   an alys is   is   v eri fi ed   ac cur ately   by   a   12 - 24   V,   30   W   conve rt er   through   PS IM   simul ation   soft ware   and   th e   r esult s   ensure s   t hat   ov eral l   eff icienc y   of   th e   conve rt er   has   im prove d   to   97 %   al ong   with   elimi na ti on   of   cur ren t   stress.   Ke yw or d s :   Digital   co ntr oller   High   c urren t   stress   Im prov e d   z vzc t   boos t   c onve rter   L - C - S   res onant   netw ork   So ft - switc hing   This   is   an   open   acc ess   arti cl e   un der   the   CC   BY - SA   l ic ense .     Corres pond in g   Aut h or :   An a ndh   N .,     Dep a rtme nt   of   Ele ct rical   and   Ele ct ro nics   E nginee rin g,   M a nip al   I ns ti tu te   of   Tech nolo gy,   M a nip al   Acad e my   of   Higher   Ed ucati on,   M a nip al   -   576104,   Ka rn at a ka,   India.   Emai l:   anand h.n@ mani pal.edu       1.   INTROD U CTION   M ode rn   era   de al s   with   ne w   powe r   el ect r onic   te ch no l og ie s   to   sat isfy   the   needs   a nd   r eq uireme nts   of   industries.   High   f re qu e nc y   DC - DC   co nverter s   a re   pr edomina ntly   util iz ed   to   se rv e   in dustria l   nee ds.   Converte rs   wi th   high   fr e qu e nc y   has   more   adv a ntage s   c ompare d   to   l ow   f reque ncy   op e rati ons,   in c reased   fr e qu e nc y   pro vid es   la r ge   po wer   de ns it y,   quic k   res pons e ,   re du ct i on   in   phys ic al   siz e,   cost   a nd   weig ht   of   reacti ve   el eme nts.   Be si des   th ese   me rits,   it   a lso   offer s   dem erit s   s uch   as   hi gh   s witc hing   losses   an d   stres s,   poo r   eff ic ie nc y   an d   el ect romag net ic   inter fer e nce   noise .   T hese   diff ic ulti es   ca n   be   recti fie d   with   s oft - s witc hin g   te chnolo gies   a nd   the y   a re   of   mainl y   f our   typ e s,   i)   Ze ro - Vo lt age   S witc hing,   ii)   Zer o - Current   Sw it c hing,   iii)   Zero - Vo lt age   Transi ti on ,   iv)   Zero - Cu rr e nt   Transi ti on .   Among   the   f our ,   fi rst   two   s witc hin g   te c hn i qu es   mainly   deals   with   inc reasin g   ef fici ency   an d   reduc ing   t he   los ses   but   it   do es   not   account   on   s witc h   stres s,   but   the   seco nd   t wo   tra ns it ion   te c hn i ques   prov i des   hi gh   e ff ic i enc y,   reduce d   losse s   an d   switc h   stress.   Apart   f rom   the   Evaluation Warning : The document was created with Spire.PDF for Python.
In t J  P ow Elec   & Dri S ys t   IS S N: 20 88 - 8 694       An  i mp r ove d  z ero - v olta ge  zer o - c ur re nt tra nsi ti on  bo os t c onvert er em plo yi ng L - C - S  …  ( A nandh N )   1845   mentio ned   te c hn i qu e s,   the re   is   ano the r   te chn i qu e   t hat   com bin es   bo t h   ZVT   a nd   ZC T   methods ,   ca ll ed   as   ZVZCT   te c hniqu e   w hich   offe rs   a dv a ntage s   of   both   the   te c hn i qu e s   [1 - 10] .     An   act i ve   s nubber   cel l   based   Z VZCT   boos t   conve rter   was   i ntr oduce d   w he rein   the   snu bb e r   cel l   plays   a   r ole   in   pr ov i ding   Z VT   an d   ZCT   f or   mai n   switc h   of   the   c onve rter   [1].   A   ZV T/ZC T/PW M   s nubber   c el l   based   conve rter   was   repor te d   in   w hi ch   the   cel l   off ers   Z VT   tu r n   on   a nd   ZCT   tu r n   off   f or   main   switc h   by   em pl oy in g   sing le   quasi   r eso nating   net work   [ 2].   A   s nubber   cel l   ba sed   Z VT/ZCT   DC - DC   c onve rter   was   i ntr oduce d,   wh e re   ad diti on al   cur re nt/v oltage   stress   a re   ne glect ed   on   mai n   switc h   a nd   c urren t   stre ss   on   add it io nal   swi tc h   is   reduce d   by   c ouplin g   in duct ance   [ 3] .   A   ne w   snu bb e r   c el l   ba sed   Z VT - Z CT   co nverte r   was   prese nted   w hich   increases   the   c onve rter   e ff ic i ency,   powe r   de ns it y   a nd   re duces   t he   E M I   no ise   [ 4].   In   Z CZVT   quasi - r eso nan t   bu c k   c onve rter ,   w her e   an   act i ve   s nubber   net work   re nd e rs   ZVT   tu r n   on   a nd   ZCT   tu rn   off   c ollec ti vely   for   the   switc hes   pr ese nt   in   the   co nve rter   with out   an y   ot her   vo lt age   and   c urren t   str ess   [5].   A   zer o - volt age/ze r o - c urrent   transiti on   co nv erter   usi ng   s nubb e r   was   de ve lop e d   in   [6],   wh e re   the   oper at ion   w as   ve rif ie d   on   a   high   powe r   conve rter   wh e r ei n   a   high   e ff ic ie ncy   of   a bout   98%   w as   ob ta i ned   at   100   kHz   switc hi ng   f requen c y.     A   t hr ee - le vel   half   bri dge   Z VZCS   P WM   DC/DC   c onve r te r   was   i ntr oduced   wh e rein   ZVS   a nd   ZCS   are   ac hiev ed   t hro ugh   pa rasit ic   in du ct a nce   of   tra nsfo rme r ,   s nubber   ca pa ci tors   an d   ta p pe d   in duct or   ty pe   smoothi ng   filt er,   this   c onve rte r   does   not   poss ess   ancil la ry   re so na nt   ci rc uit   to   obta in   s oft - s witc hing   [ 7].   A   ne w   ZVZCT   boos t   conve rter   em ployin g   a   c oupling   in du ct or   was   dev el ope d,   in   w hich   t he   switc hes   a nd   diodes   unde rgo   soft - s witc hing   an d   i mpro ves   the   e ff ic ie nc y   with   re duced   ci rc ul at ing   c urre nt   due   to   the   c ouplin g   eff ect   [ 8].   An   op ti mize d   Z VZCT   boos t   c onve rter   wa s   achieve d   by   usi ng   a   c ouplin g   in du ct or,   the   main   adv a ntage   of   t his   to polo gy   is   that   the   ste ad y - sta te   c onditi on   of   m ai n   s w it ch   c an   be   opti mize d   by   fixi ng   the   couplin g   in duc ta nce   r at io   f or   each   desire d   l oad   [ 9].   A   s of t - switc hi ng   bo ost   co nv e rter   wi th   co uple d   i nd ucto r   and   an   e xtra   s witc h   wa s   anal yzed,   he re   the   coupled - in duct or   delive rs   the   energ y   to   the   load ,   w hich   mi nimize s   the   a ux il ia r y   s witc h   c urre nt   stress   a nd   al s o   hel ps   in   imp r ov i ng   the   e ff i ci ency   of   co nverter   [10].   V oltage - mu lt ipli er   cel l   an d   c ouple d - inducto rs   i ntegr at e d   high   st at ic   gain   DC/ DC   s of t - switc hing   c onve rter   was   pr ese nted ,   in   wh ic h   t he   mu l ti plier   cel l   al ong   with   c oupl ed - i nducto rs   pl ay   a   vital   ro l e   in   re duci ng   switc h   vo lt age ,   c ondu ct ion   l os ses   an d   it   al s o   im pro ves   t he   e ff ic ie nc y   [11 ].   A   ma gnet ic al ly   co upl ed   a uxil ia ry   ne twork   base d   ZCZ VT   inve rter   is   propose d   in   [12],   w hic h   ov e rc om es   the   react ive   e nergy   pro blem   a nd   im pro ves     the   ef fici enc y.     A   ZCZVT   c ommutat io n   cel l   base d   DC/D C   P WM   c onve rter   was   a ddr essed   [ 13]   w hi ch   offe rs   t he   ben e fits   of   bo t h   s oft - tra ns it io n   meth ods.   A   c om m utati on   ce ll   base d   tr ue   Z CZVT   DC/DC   P WM   c onve rter   was   exp la ine d   in   wh ic h   c ommu ta ti on   cel l   off ers   ZC S   a nd   ZVS   f or   mai n   switc h   duri ng   tur n   off   an d   tur n   on   simult ane ou sl y   [ 14].   A   hi gh   e ff ic ie nt   ZV ZCT   c onve rter   for   batte r y   cel l   e qu al iz at io n   wa s   a ddresse d   w her ei n   by   em ployin g   the   volt - sec   balance   pri nci ple   of   in du ct or   a nd   tra ns f or mer   c oupli ng,   the   batte r y   c el ls   are   equ al iz e d   a nd   by   incl ud i ng   a ncill ary   res ona nt   netw ork   at   the   mai n   s witc hing   de vices,   ZV S   a nd   ZC S   are   achieve d   with   el imi nation   of   losses   [ 15].   A   sy nc hro nous   r ect ific at ion   ba sed   ZCZV T   forw a rd   c onve rter   wa s   introd uced,   w he rein   the   c onve rter   is   operate d   with   s ynch r onous   recti ficat ion   to   minimi z e   cond uction   l os ses   of   the   recti fier   at   load   side   a nd   to   im prove   the   ove rall   eff ic ie ncy   to   89%   [ 16].   A   s of t - s wi tc hin g   ZCZVT   boos t   powe r   c onver t er   was   a nalyz ed   a nd   a   cl ass ic al   con tr oller   was   desi gn e d   in   order   to   ne gl ect   sour ce   vo lt age   var ia ti on   a nd   to   at ta in   l oad   volt age   regulat ion   [ 17].   A   zer o - volt ag e   transiti on   fif th - order   boos t   conver te r   un derg oes   soft - s witc hing   f or   t he   switc hi ng   dev ic es   a nd   al so   vo lt age - m ode   di gital   con t ro ll er   for   the   conve rter   hav e   been   disc u sse d   in   [18 ].   A   LCLC   resona nt   netw ork   base d   bid i recti on al   s of t - switc hing   DC/ DC   c onve rter   was   anal yzed,   this   co nverter   is   an   impro ved   ve rs ion   of   tra diti onal   bid irect io na l   co nv e rter   by   rep la ci ng   the   isolat ion   tra ns f ormer   wit h   LCLC   resona nce   ci rc uit   to   achie ve   hi gh   e ff ic ie nc y   with   high   boost   rati os   [ 19].   An   e nh a nce d   z ero - volt age   tra ns it ion   boos ti ng   c onve rter   was   intr oduce d   in   w hic h   a   LCS   res onant   cel l   is   emp loy e d   to   at ta in   the   soft - s witc hing   of   the   de vices,   to   impro ve   ef fici ency   an d   to   el i minate   the   pea k   c urren t   s tress   of   the   co nvert er   [ 20] .     A   s oft - s witc hin g   inte rleave d   bo os t   c onve rter   for   f uel   cel l   ap plica ti on   w as   pr opos e d,   in   w hich   tw o   simi la r   boos t   conve rters   a re   co nn ect e d   in   par al le l   an d   con t ro ll ed   by   interl eave d   s w it ching   si gnal s.   This   conve rter   is   w idely   us e d   f or   hi gh   ef fici en cy   fu el   cel l   powe r   sy ste m s   in   wh ic h   it   im pro ves   t he   el e ct rical   performa nce,   e ff ic ie nc y   an d   it   al so   reduces   t he   switc hing   loss,   siz e   a nd   weig ht   of   the   c onve rter   [ 21].   A   ne w   zero   vo lt age   tr ansiti on   bid ire ct ion al   DC - DC   co nverter   was   intr odu ce d   f or   batte r y   bac k - up   s ys te ms   in   hybri d   el ect ric   veh ic l es,   w hic h   re duces   t he   tu rn - on   switc hing   losses,   switc h   cu rr e nt   stres s   an d   im pro ve s   the   eff ic ie nc y   [ 22 ].   A   rev ie w   of   va rio us   soft - switc hing   te ch niques   wa s   ca rr ie d   out   base d   on   the   to po logy,   resona nt   c irc ui t   locat ion,   perf ormance   ch ara ct erist ic s   an d   pri nciple   of   ope rati on.   In   ad dit ion ,   c onver te rs   area   of   ap plica ti on ,   merit s   an d   de merit s   are   al so   addresse d   [23 ].             Evaluation Warning : The document was created with Spire.PDF for Python.
               ISSN :   2088 - 8 694   In t J   P ow  Ele c  &  D ri   S ys t,   V ol .  11 , N o.   4 ,  D ecembe r  2020   :   18 44   –   1 856   1846   2.   ANALY SIS   A ND   PR IN CIP LE   OF   OPE R ATIO N   OF   I ZVZCTB C   The   pro po se d   Im pro ved   Ze ro - V oltage   Ze ro - Cu rr e nt   Tra ns it ion   B oost   Converte r   is   presente d   in   Figure   1.   N ormal ly,   an   a ux il ia ry   net work   c omprisin g   of   a dd it io nal   s witc h,   di od e ,   i nduc tor   an d   capaci t or   are   su f fici ent   to   re al iz e   the   reson ance   phe nome non   in   t he   co nverter   w hich   offe rs   hi gh e r   ef fici ency   an d   re du ce d   switc hing   l os s es,   but   the re   is   a   huge   cu rr e nt   stress   an d   co nductio n   losses   acro s s   the   mai n   s witc h.   In   or der   to   avo i d   this ,   a   sl igh t   m odific at ion   in   t he   a ux il ia ry   netw ork   is   done   by   a dd ing   one   m or e   series   in duct or   with   main   switc h   a nd   the   pro pose d   L - C - S   res on ant   netw ork   c omp rised   of   a uxil ia ry   s witc h   (S Aux ),   a uxil ia ry   di ode   (D Aux ),   res onat ing   i nducto r   (L r ),   re sonat in g   c apacit or   (C r )   a nd   a   main   serie s   inducto r   (L Main ).   T he   res ona nce   is   ta kin g   place   a mong   t he   a ux il ia ry   s of t - switc hing   ca pacit or   (C r )   an d   e ne rgy   tra ns fe rr i ng   i nducto r   (L r ).   A lso,   for   a   short   i nter val   of   per io d,   the   resonati ng   ca pa ci tor   e xch a ng es   ene rgy   with   the   par al le l   co mb inati on   of   L r   an d   L Main .   Prop e r   s el ect ion   of   C r ,   L r   an d   L Main   will   be   vital   for   a chievin g   t he   IZ VZCT   operati on.   Fo ll o wing   are   the   ass umpti ons   to   be   ma de   in   or der   to   ma ke   the   anal ys is   simpler.   At   in pu t   si de,   t he   existe nce   of   huge   in duct or   (L 1 )   in   se ries   with   volt age   sou rce   has   bee n   s ub sti tute d   with   the   ma gn it ude   of   I g   (constant   s our ce   current ).   At   load   side ,   the   existe nce   of   huge   ca pacit or   (C o )   in   par al le l   with   load   ha s   been   su bst it uted   with   the   mag nitu de   of   V 0   (cons ta nt   source   volt age) .   It   is   ass um e d   that   al l   the   s witc hing   de vices   and   e nerg y   st or i ng   c omp onents   are   ideal .   The   sta tus   of   ind i vidual   s witc hing   de vi ces   in   each   mode   of   IZVZC T   op e ra ti on   is   giv e n   in   the   Ta ble   1.   Wav e f or m s   of   vo lt age s   a nd   c urren ts   acr os s/ thr ough   the   di f fer e nt   switc hes   durin g   one   cycle   of   op e rati on   are   s how n   in   Fig ur e   2,   Fig ure s   3   &   4   de picts   the   structu ral   va r ia ti on s   in   Z VT/ZCT   operati ons.         Table   1.   Stat us   of   in div i du al   s witc hing   dev ic es   in   eac h   mod e   of   I ZVZCT   operati on   Mod e   of   o p eration   Tim e   d u ration   S Ma in   S Au x   D Ma in   D Au x   Mod e   1   t 0 <t<t 1   Х   √   √   √   Mod e   2   t 1 <t<t 2   Х   √   Х   √   Mod e   3   t 2 <t<t 3   Х   (Bo d y   d io d e   -   ON)   √   Х   √   Mod e   4   t 3 <t<t 4   Х   (Bo d y   d io d e   -   ON)   Х   (Bo d y   d io d e   -   ON)   Х   √   Mod e   5   t 4 <t<t 5   Х   (Bo d y   d io d e   -   ON)   Х   Х   √   Mod e   6   t 5 <t<t 6   Х   (Bo d y   d io d e   -   ON)   Х   √   Х   Mod e   7   t 6 <t<t 7   √   Х   √   Х   Mod e   8   t 7 <t<t 8   √   Х   Х   Х   Mod e   9   t 8 <t<t 9   √   √   Х   Х   Mod e   10   t 9 <t<t 10   √   √   Х   √   Mod e   11   t 10 <t<t 11   Х   (Bo d y   d io d e   -   ON)   Х   (Bo d y   d io d e   -   ON)   Х   √   Mod e   12   t 11 <t<t 12   Х   Х   Х   √   Mod e   13   t 12 <t<T s   Х   Х   √   Х       V g R l o a d D M a i n L 2 L 1 L M a i n L r C r C 0 C 1 D A u x S M a i n S A u x     Figure  1. Pro pose d  I mpr ov e d ZVZCT  Bo os t  Co nv e rter   Evaluation Warning : The document was created with Spire.PDF for Python.
In t J  P ow Elec   & Dri S ys t   IS S N: 20 88 - 8 694       An  i mp r ove d  z ero - v olta ge  zer o - c ur re nt tra nsi ti on  bo os t c onvert er em plo yi ng L - C - S  …  ( A nandh N )   1847   t 1 t 0 t 5 t 6 t 4 t 3 t 2 T s t 7 t 1 1 t 1 2 t 1 0 t 9 t 8     Figure   2.   V oltage/ Curre nt   wa veforms   of   va r iou s   switc hi ng   dev ic es   in   IZ V ZCT   ope rati on       L 2 L r C r C 1 V o I g L 2 L r C r C 1 V o I g D A S M L 2 C r C 1 V o I g D A S M D M L 2 C 1 V o I g M O D E - V I M O D E - V M O D E - I V M O D E - I I I M O D E - I I M O D E - I D A L 2 L r C r C 1 V o I g D A L 2 L r C r C 1 V o I g D A S M D M S M L M L M S A S A S A S A L M L M     Figure   3.   Str uc tural   var ia ti ons   in   Z VT   operat ion   Evaluation Warning : The document was created with Spire.PDF for Python.
               ISSN :   2088 - 8 694   In t J   P ow  Ele c  &  D ri   S ys t,   V ol .  11 , N o.   4 ,  D ecembe r  2020   :   18 44   –   1 856   1848   L 2 C 1 D M S M V o L 2 C 1 V o I g S M L 2 L r C r C 1 V o I g S M S A L 2 L r C r C 1 V o I g D A S M S A L 2 L M L r C r C 1 V o I g L 2 C r C 1 V o I g L 2 C 1 V o I g I g D A S M S A D A D M M O D E - X I I M O D E - X I M O D E - X M O D E - I X M O D E - V I I I M O D E - V I I M O D E - X I I I L M L M L M L M     Figure   4.   Str uc tural   var ia ti ons   in   ZCT   oper at ion       2.1.   Oper at in g   mode s   in   a   s witchin g   cy cl e   Mo de   I   ( t 0   -   t 1 ) :   Pr io r   to   this   m od e ,   the   ci rc uit   wa s   in   f reewh eel ing   m od e   with   mai n   diode   al one   co nduct ing .   Be fore   trigg e rin g   main   s witc h,   trig ge r   the   au xili ary   switc h   in   subs equ e nt   ti me   w hich   re du ce s   the   volt age   ac r oss   main   switc h   to   become   zer o,   be f ore   it   tur ns   ON   ( with   Z VS   co ndit ion).   The   du rati on   of   t his   mode   of   ope ra ti on   is   giv e n   by   t 1 .     In it ia l   co nd it io ns :     ( 0 ) = ,   ( 0 ) = 0 ,   ( 0 ) = 0     1 = 1 1  − 1 ( 2 )     (1)     Mo de   II   ( t 1   -   t 2 ) :   In it ia l   co nd it io ns :     ( 0 ) =  [ 1 ( 1 − 0 ) ] ,   1 ( 0 ) = −  [ 1 ( 1 − 0 ) ] ,   ( 0 ) =  [ 1 ( 1 − ) ] ,   ( 0 ) = ( 0 ) A Dg iI =     The   ti me   doma in   eq uati on   of   this   m ode   is,     2 = 1 + ( 1 1 )  − 1 [  { ( 1 − 0 ) } ]     (2)     By   the   c omplet ion   of   this   mode,   the   volt age   acr os s   m ai n   s witc h   go es   to   zer o   a nd   favo rab le   conditi ons   for   ZVS   t urn   on   of   S M   will   pre vail.     Mo de   I II   ( t 2   -   t 3 ) :   In it ia l   co nd it io ns :   Evaluation Warning : The document was created with Spire.PDF for Python.
In t J  P ow Elec   & Dri S ys t   IS S N: 20 88 - 8 694       An  i mp r ove d  z ero - v olta ge  zer o - c ur re nt tra nsi ti on  bo os t c onvert er em plo yi ng L - C - S  …  ( A nandh N )   1849   ( 0 ) 0 r C v = ,   ( 0 ) = ,   ( 0 ) = − [  { ( 2 − 1 ) − 1 ( 1 − 0 ) } ]     Durin g   t his   mode,   res onat ing   c apacit or   sta rts   c hargi ng   an d   main   induct or   c ur ren t   e quat ion     ob ta ine d   is ,     ( 1 ) = − 2 [  { ( 2 − 1 ) − 1 ( 1 − 0 ) } ]     (3)     Mo de   IV   ( t 3   -   t 4 ) :   Re so natin g   ca pacit or   (C r )   c ha rg es   to   its   f ul l   value   be f or e   this   mode .   D ur i ng   t his   m ode, = ,   main   in duct or   (L M )   c harges   li near l y   th rou gh   a   ste ad y   s ource   cu rr e nt   (I g ).     Mo de   V   ( t 4   -   t 5 ) :   In   this   m ode,   main   s witc h   is   switc he d   OF F   in   ha r d - s witc hi ng   co ndit ion .     Mo de   VI   ( t 5   -   t 6 ) :   This   durati on   is   eq uiv al e nt   to   fr ee - w heeli ng   i nter v al   of   tra di ti on al   bo os t   c onve rter.     Mo de   V II   ( t 6   -   t 7 ) :   The   ti me   doma in   eq uatio n   of   this   m ode   is,     7 = ( 2 + ) 0     (4)     Mo de   V III   ( t 7   -   t 8 ) :   In   this   i nter val,   a   ste ady - sta t e   current   e qu a l   to   I g   flo ws   t hro ugh   the   ma in   switc h   a nd   thi s   interval   exists   till   the   fi rin g   of   a uxil ia ry   s witc h.     8 = ( D - D Sau x )     (5)     Mo de   IX   ( t 8   -   t 9 ) :   This   m od e   begi ns   with   the   s witc hing   ON   of   a uxil ia ry   s witc h   an d   the   ti m e   domain   eq ua ti on   is   giv e n   by   t 9 ,   I niti al   co nd it io ns :     ( 0 ) = ,   ( 0 ) = 0 ,   ( 0 ) = 0   9 = 8 + 2 √     (6)     Mo de   X   ( t 9   -   t 10 ) :   In it ia l   co nd it io ns :       ( 0 ) = ,   ( 0 ) = 0 ,   ( 0 ) = 0 ,   2 ( 0 ) = 0 ,       and   the   ti me   domain   eq uatio n   of   this   m ode   is,     10 = 9 + [ 1 ]  − 1 [ { − √ 1 + /  ( 9 − 8 ) } + 1 ]     (7)     Mo de   XI   ( t 10   -   t 11 ) :   The   ti me   doma in   eq uatio n   of   this   m ode   is,     11 = 9 + [ 1 ] [ +  − 1 { − 1 + ( √ 1 + / s i n ( ( 9 − 8 ) ) ) } ]     (8)     Mo de   X II   ( t 11   -   t 12 ) :   Durin g   t his   m ode,   t he   mai n   di od e   volt age   wi ll   be   dec reasi ng   as   the   res on a ti ng   ca pacit or   is   cha rg i ng.     12 = 11 + [ { − Si n [ { ( 9 − 8 ) } { Si n [ ( 11 − 10 ) ] } ] ( √ 1 + / ) } ]     (9)     Evaluation Warning : The document was created with Spire.PDF for Python.
               ISSN :   2088 - 8 694   In t J   P ow  Ele c  &  D ri   S ys t,   V ol .  11 , N o.   4 ,  D ecembe r  2020   :   18 44   –   1 856   1850   Mo de   X III   ( t 12   -   t 13 ) :   In   t his   inter val,   main   diode   c urren t   reache s   a   ste ady - sta te   value   a nd   thi s   interval   pr e va il s   ti l l   the   main   s witc h   is   tur ned   ON   at ,   13 = .         3.   GATI NG   SEQUEN CE   AND   DESIG N   OF   POWE R   STAGE   COMP ONEN T S   Gati ng   seq ue nc e   requirem en t   in   case   of   i mpro ve d   ZV Z CT   scheme   is   pr ese nted   in   Figure   5 .   Accor ding   to   the   disc us sio n,   the   m odifie d   scheme   offe r s   certai n   a dva ntages   f or   e xe cution   of   IZVZC T   op e rati on.   In   this   t he   switc hi ng   patte rn   is   s yn c hro nized   s uc h   t hat   it   help s   in   real   ti me   i mp le me ntati on.   In   case   of   nor mal   Z V ZCT   ope rati on,   the   first   pulse   of   S A,   in   w hich   the   asce nd i ng   si de   of   main   switc h   gatin g   sign al   mu st   be   matc he d   with   desce ndin g   si de   of   the   au xili ary   swi tc h   gating   puls e,   this   pulse   is   cal le d   ZV S   pulse   f or   aux il ia r y   switc h   an d   the   sec ond   pu lse   of   S A ,   in   w hich   the   desce nd i ng   si de   of   S M   an d   S A   gate   pulse s   s hould   coincide   (s houl d   be   withdra w n   sim ultane ou s ly).   This   pulse   is   cal le d   ZCT   pu lse   f or   the   a ux il ia r y   s witc h.     In   the   modifie d   ver si on   of   Z VZCT   operati on,   e ven   afte r   S M   is   switc hed   O N,   t he   gate   pu lse   of   S A   is   to   be   co ntin ue d   for   s om e   e xt end e d   ti me,   to   achieve   t he   s oft - switc hing.   T hi s   is   cal le d   ti me   delay   1   w hic h   sta rts   betwee n   t he   st arti ng   of   t he   ga ti ng   pu lse   f or   main   switc h   a nd   the   i ns ta nt   of   with dr a wing   the   ga ti ng   pulse   to   aux il ia r y   s witc h.   Simi la rly,   e ven   afte r   the   S M   is   switc he d   OFF,   t he   gate   pulse   of   S A   is   to   be   c onti nued   for   so me   exte nd e d   ti me,   in   or der   to   achie ve   t he   so ft - switc hi ng   and   this   is   cal le d   ti me   delay   2   betwee n   t he   instant   of   with dr a wal   of   the   gate   pu ls e   f or   S M   an d   the   instant   of   wit hdra wing   the   ga te   pu lse   to   S A .   On   obse rv i ng   the   gate   pulse   require ment   ne eded   f or   the   aux il ia r y   s witc h   for   both   Z V T   an d   ZCT   op e rati ons,   it   has   been   t ho ught   to   a pply   t he   co mb i natio n   of   bo t h   puls es   as   de picte d   in   Fig ur e   5.   Her e ,   the   aux il ia r y   s witc h   will   be   s witc hed   twic e   as   c ompare d   to   the   main   s witc h   in   a   giv e n   s witc hing   c ycle.   In   oth e r   words,   the   s witc hin g   fr e quen cy   of   S A   will   be   t wice   t hat   of   S M .   T he   d e sign   par am et er s   of   the   c onve rter   a re   giv e n   belo w   in   Table   2.         A u x i l i a r y   s w i t c h   g a t i n g   p u l s e M a i n   s w i t c h   g a t i n g   p u l s e S M S A T D 2 T D 1 Z C T   P u l s e Z V T   P u l s e T i m e T i m e     Figure  5. Gati ng se quence  r e quireme nt in  I Z VZCT sc heme   Table  2.   Desig n values  of  power sta ge  com pone nts   Para m eters   Desig n  valu es   Po wer  o u tp u t ( P o )   30  W   Ou tp u t  v o ltag e ( V o )   24  V   Switch in g  f requ en cy  ( f s )   100  kHz   Inp u t  in d u cto r  1  ( L 1 )   120  µH   Inp u t ind u cto r  2  ( L 2 )   25  µH   Main in d u cto r  (L M )   0 .7  µH   Load  capacito r  1 ( C 0 )   200  µF   Load  capacito r  2   ( C 1 )   52  µF   Res o n an ce ind u cto r  ( L r  )   0 .5  µH   Res o n an ce c ap acito r  ( C r )   2 00  nF         3.   1.   Nece ssa r y and su ff ic ie nt   c on di tion s  for IZ VZCT  oper ati on   In   order   to   ach ie ve   IZ VZCT   op e rati on,   the   necessa ry   a nd   su f fici ent   co nd it ion s   will   be   s ame   as   that   of   Z VZCT   m odes   of   operati on.   In   oth e r   w ords,   the   durat ion   of   the   au xi li ary   s witc h   p ulse   durin g   Z VT   an d   ZCT   ca nnot   be   the   same .   If   they   are   sa me,   f or   the   posit ive   va riat ion   of   t he   l oads,   the   vi olati on   of   t he   ZCT   so ft - switc hi ng   happe ns   al th ough   ZVT   may   be   sti ll   sat isfyin g.   Her e ,   the   in pu t   a nd   outp ut   op e rati ng   co nd it ions   are   set   suc h   t hat   Z CT   is   s at isfie d   ov e r   wide   ra nge.   If   th e   c onve rter   sat isfie s   the   ZCT   t he n   Z VT   is   automatic al ly   ens ur e d   but   vi ce - ve rsa   is   not   true.   In   su c h   case,   certai n   operati ng   c onditi on s   may   sat is fy   t he   ZVT   w hile   vi olati ng   the   Z CT   co ndit ion s .   T he   ab ove   i nformat ion   is   du e   to   t he   des ign   of   the   co nverter .   Ba sic al ly,   it   is   done   for   ac hi eving   ZCT   a nd   by   em ploy ing   s uitable   ga ti ng   se qu e nce   ZVT   a nd   IZ VZCT   op e rati ons   can   al so   be   ac hieve d.   On   obser ving   the   necessar y   and   s uffici ent   conditi ons   f or   bo t h   the   op e rat ion s ,   the   durati on   o f   ZVT   pulse   re qu i reme nt   is   le sser   tha n   t he   durati on   of   ZCT   pu lse .   In   oth e r   wor ds ,   for   the   same   ZVT   a nd   ZCT   pu lse s   of   t he   aux il ia r y   switc h,   the   mar gin   in   achie ving   Z VT   is   m or e   as   com par e d   to   Z CT   for   po sit ive   loa d   c hanges .         4.   DESIG N   OF   VOLTA GE - MO DE   CON TROLL E R   As,   t his   higher - orde r   c onve rt er   is   e xperienc ing   dif fer e nt   t opologica l   var i at ion s   over   one   switc hi ng   cycle.   Due   to   this,   it   is   a   c ha ll eng in g   ta s k   to   ac hieve   the   trans fer   f un ct ion   of   the   s ys te m   by   sta te - sp ace   Evaluation Warning : The document was created with Spire.PDF for Python.
In t J  P ow Elec   & Dri S ys t   IS S N: 20 88 - 8 694       An  i mp r ove d  z ero - v olta ge  zer o - c ur re nt tra nsi ti on  bo os t c onvert er em plo yi ng L - C - S  …  ( A nandh N )   1851   appr oach.   He nc e,   by   e mp l oy i ng   s ys te m   ide nt ific a ti on   t oo l   a nd   by   P   &   O   m et hod,   the   s ys t em   trans fer   fun ct ion   is   ob ta ine d   for   IZ VZCT   op erati on   with   s uitable   inter va l   (g reate r   tha n   85%).   Im ple mentat io n   of   analo g   con t ro ll ers   a re   al ready   existi ng   a nd   now - a - days   di gital   con tr ollers   are   m or e   fo c us e d   be cause   of   thei r   add e d   merit s   s uch   as   le sser   se ns it ivit y   to   noise ,   gre at er   se ns it ivit y   to   c ha ng e s   in   par a mete rs   an d   le ss   vu l ner a bili ty   to   agin g   a nd   en vi ronme ntal   issu es.   Among   dif fere nt   co ntr ol   te chn i qu e s,   the   vo lt age - m ode   scheme   is   bet te r   an d   high ly   ef fecti ve.   Fu rt her,   it   pro vid es   good   dynamic   re spo nse   an d   al so   t here   is   no   sta bili ty   pr ob le m s.   T hu s ,   a   dig it al   vo lt age - mode   c ontrolle r   is   e mp l oy e d   for   t he   m odifie d   Z VZCT   co nverter .   T he   tra ns fe r   f un ct io n   of   the   pla nt   G p (z)   f or   IZVZC T   opera ti on   has   been   obta ined   with   t he   h el p   of   s ys te m   ide ntific at io n   t oo l   an d   this   is   gi ven   in   e quat ion   10.   Ou t pu t   Er r or   ( OE)   meth od   has   bee n   a da pted   a nd   for   a   best   fit   of   88. 9% ,   the   tran sfe r   functi on   ob ta in ed   is     ^ ( ) ^ ( ) = − 0 .00313 4 z 3 +0 .127 1 z 2 − 0 .1 5 5 6 z + 0 .005 9 8 2 4 − 3 . 83 8 3 +5 .519 z 2 − 3 .5 2 5 z + 0 . 84 34     (10)     The   volt age - m od e   co ntr oller   is   desi gn e d   c on siderin g   t he   a bove   tra ns fe r   functi on   of   open   loop   s ys te m   is ,     ( ) = 0 . 10635 ∗ ( − 0 . 8 75 ) ( − 0 . 9 61 ) ( − 1 ) ( − 0 . 9 12 )     (11)     Util iz ing   the   tr ansf e r   functi on s   of   plant   (G p (z )) ,   co mp e ns at or   (G c (z )),   a nd   loop   gain   is   e xpresse d   as,     T L   (z)   =   G p   (z)   G c   (z )     (12)     Figure   6   de picts   the   cl os e d   l oop   blo c k   diag ram   of   the   c onver te r .   The   G M ,   PM   a nd   BW   val ues   f or   the   desig ne d   c on t ro ll er   are   a chieve d   fro m   t he   bode   plo ts   of   the   op e n   lo op   tra nsfer   f un ct ion   of   c onve rter   a nd   al so   with   c on tr oller   im plemen ta ti on   are   sho w n   in   Fig ure s   7   and   8.     G c ( z ) G v d ( z ) G v g ( z ) Z o ( z ) + - + + + + + + V r e f e o i C O N T R O L L E R C O N V E R T E R o v g v d u     Fi gure  6. Bl oc k diag ram of  cl os e d  lo op s ys te m       .     Figure  7. Fr e quenc y res pons e  ch a racteri sti cs of IZVZCTB C   Evaluation Warning : The document was created with Spire.PDF for Python.
               ISSN :   2088 - 8 694   In t J   P ow  Ele c  &  D ri   S ys t,   V ol .  11 , N o.   4 ,  D ecembe r  2020   :   18 44   –   1 856   1852   Figure  8  in fer s   that,   the  G M  is  10. 5  dB,   P M   is   33. 5 0   an d  the   gai n  c ro s s ov e r  fr e quen cy   is  416  Hz ,  wh ic h  are  al l  sat isfying  sta bi li ty  crit eria  for  the  desig ne d  con t ro ll er .  T he   fr e quenc y  re sp onse  plo ts  of  the  Converte r  ( G p  ( z)) ,  Co ntr oller  (G c  ( z) )  a nd Loop gai n (T L  (z ) )  are  s how n  in   Figure  9.           Figure  8. PZ  m ap  a nd freq ue nc y respo ns e  pl ot of  IZVZC TBC       Figure   9.   Bo de   plo ts   of   IZVZ CTB C   [Conve r te r   (b l ue) ,   Co mp e ns at or   (green )   and   L oop   gain   (r e d)]   (GM= 10.5   dB,   PM = 33. 5   de g,   f c =4 16Hz )         5.   VA LI D ATIO N   OF   CONTROLL ER   PE RFO R MANCE   FOR   IZVZ CT   OPE R ATION   The   desig ne d   dig it al   co ntr oller   has   bee n   ver ifie d   for   dif fer e nt   in put   an d   outp ut   va riat ion s   in   simulat ion.   L oa d   va riat ion   of   ou t pu t   resist an ce   from   20   Ω   to   36   Ω   has   bee n   gi ven   an d   a fter   10   ms   the   volt age   of   the   c onve rt er   got   re gu la te d   within   2   ms   by   the   co ntr oller   act io n.   A   sudd e n   va riat ion   of   12   V   to   15   V   is   app li ed   to   the   so urce,   w hich   in   tu r n   ma de   t he   transie nts   to   die   do wn   withi n   2   ms   a nd   al so   the   pe rfo rma nce   of   the   co ntr oller   was   sat isfact ory   a nd   the   matc hing   resu lt s   a re   de picte d   in   Fi gure   10 .   Ra mp   disturba nce   of   12   V   to   15   V   from   2 0   ms   to   60   ms   has   been   giv e n   as   the   in pu t,   in   w hich   it   made   the   t ransi ents   to   die   dow n   within   2   ms   an d   al so   t he   pe rfo rma nc e   of   c on t ro ll er   is   sat isfact ory .   The   corres pondin g   resu lt s   a re   s ho wn   in   Fig ur e   11 .           Figure  10. D ynamic  r es pons e   char act e risti cs o f   IZVZC TBC ,   ( R  = 20  -   36  Ω  at  t = 10 m s; V g   = 12  -   15  V   at  t =  20  ms)       Figure  11. D ynamic  r es pons e   char act e risti cs o f   IZVZC TBC , ( V g   =  12  -   15  V  f r om 2 0  -   60  ms )           - 1 0 0 - 5 0 0 50 100 M a g n i t u d e   ( d B ) 10 0 10 2 10 4 - 1 8 0 0 180 360 P h a s e   ( d e g )     B o d e   D i a g r a m F r e q u e n c y     ( H z ) G v d z _ Z V Z C T G c z _ Z V Z C T L o o p _ Z V Z C T Evaluation Warning : The document was created with Spire.PDF for Python.
In t J  P ow Elec   & Dri S ys t   IS S N: 20 88 - 8 694       An  i mp r ove d  z ero - v olta ge  zer o - c ur re nt tra nsi ti on  bo os t c onvert er em plo yi ng L - C - S  …  ( A nandh N )   1853   6.   RESU LT S   A ND   DI SCUS S ION     As   ex plaine d   a lread y,   the   pea k   in   the   m ai n   s witc h   cu rr e nt   duri ng   tu r n   ON   transiti on   is   present   in   the   case   of   c onve nt ion al   ZVZCT   netw orks   a nd   t he   relat ively   la rg e   ne gative   pe ak   in   mai n   s witc h   cu rr e nt   will   be   el imi nated   by   inco rpor at in g   t he   imp r ov e d   s of t - switc hi ng   c el l   un de r   c on si der at io n   int o   the   co nverter .   Figure   12.   dep ic ts   t he   el imi nation   of   main   s witc h   c urre nt   stress   of   I ZVZCTBC .             Figure   12.   Eli minati on   of   ma in   switc h   c urre nt   str ess       Figures   13,   14,   15   a nd   16   de pi ct s   the   volt age /c ur re nt   wa veforms   of   main   a nd   a uxil ia ry   s witc h,   mai n   and   au xili ary   di od e.   From   the se   Fig ur e   s,   it   can   be   c on cl uded   that   al ong   with   mai n   a nd   aux il ia r y   s witc hes   the   L - C - S   ta nk   ne twork   is   al s o   capab le   of   pro vid in g   soft - tra ns it ion   co ndit ion s   for   m ai n   and   a ux il ia r y   diodes,   wh e reas   in   c onve ntio nal   Z V ZCT   net wor ks   it   can   be   noti ced   t hat   it   is   pro vid in g   soft - switc hing   c on diti on s   pr ima rily   for   S M   and   is   not   a ddressi ng   the   ha rd - switc hing   prob le m   of   oth e r   switc hing   de vices.           Figure   13.   M ai n   s witc h   volt ag e   &   c urren t       Figure   14.   A uxil ia ry   switc h   volt age   &   c urre nt       Figure   15.   M ai n   diode   vo lt a ge   &   c urren t       Figure   16.   A uxil ia ry   di od e   vol ta ge   &   c urre nt       The or et ic al   los ses   an d   ef fici ency   stu dy   f or   s of t   a nd   ha rd - s witc hed   co nve rters   has   been   done   a nd   the   resu lt s   a re   de pi ct ed   in   Fig ur e   s   17   an d   18.   Fr om   t he   plo ts ,   it   is   cl ear   t ha t,   at   li gh te r   loa ds ,   the   e ff ic ie nc y   of   hard - switc he d   conve rter   is   po or   a nd   i ncr ea s es   for   inc reasi ng   l oad s .   T he   eff ic ie nc y   will   be   ma ximum   ar ou n d   nominal   operat ing   point,   wh e r eas   in   case   of   s of t - switc he d   c onve rter,   its   li ght   loa d   ef fici en cy   is   al so   bette r   a nd   is   al mo st   co ns t ant   thr ough ou t   the   vast   var ia t ion   in   loa d.   T he   ef fici enc y   of   ha rd - s witc he d   co nverte r   is   about   89%   at   rate d   load   a nd   it   is   a bout   97%   in   c ase   of   s of t - swi tc hed   c onver te r.   Th e   t heoreti cal   ef fici encies   of   both   hard   a nd   soft - switc he d   c onve rters   ha ve   be en   plo tt ed   for   the   sa me   rated   loa d   a nd   e xa mined   that   the   soft - switc he d   c onve rter   is   res ulted   in   imp r ov e d   eff ic ie nc y   of   a bout   5   to   8% .     Evaluation Warning : The document was created with Spire.PDF for Python.