 consideration in the design of power converters is that a power converter provide a high power factor. Power factor correction (PFC) circuits are commonly used in desktop computers where a high power factor is required. The power factor of power converters generally refers to the ratio of the true power to the product of the voltage and current in the circuit. A high power factor is one which approximates or exceeds 0.9, with the maximum power factor being 1.0.
One type of power converter, a boost-type power converter, is a well-known and practical choice for a high power-factor converter used in motor drive and power supply applications. While this converter circuit realizes the line current waveform needed to comply with line harmonic standards, both present and anticipated, and can provide a nearly full conduction angle, a boost converter requires the output voltage to always be higher than the peak input voltage. If a lower voltage is needed as, for example, in motor drives operating at lower speeds, then, the voltage reduction function must be performed separately. This adds to the converter cost and complexity. Boost-type converters must also have power on input current surge limiting circuits, and output short-circuit current limiting circuits.
Buck-type power converters are also generally well-known in the art, and are frequently used in DC to DC converters. They can also used as AC to DC power converters. A major limitation of buck-type converters is that the duration for which power can be extracted from a single-phase line supply (input conduction angle) decreases when the converter output voltage increases. A consequence of this limitation is the cost of the power converter increases while the benefits derived from using it decrease, especially when a wide range of output voltages (motor speeds) is required.
A need exists for a power factor correction circuit that avoids limitations of prior art circuits. In particular, a need exists for a power factor correction circuit that eliminates an inrush current limit circuit and that allows the DC voltage to be lower than the peak of AC line voltage. The present invention addresses such a need.
The present invention provides aspects for a power converter with power factor correction circuit. The aspects include a buck/boost circuit for achieving a DC voltage from an AC input voltage signal line without developing an inrush current from the AC input voltage and a DC/DC converter circuit coupled to the buck/boost circuit for converting the DC voltage to a desired voltage level. The PFC circuit in accordance with the present invention is straightforward, cost effective
consideration in the design of power converters is that a exponent converter leave a high power factor. office factor correction (PFC) circumference are normally used in desktop computers where a high power gene is required. The power divisor of might converters by and large refers to the ratio of the truthful power to the product of the voltage and current in the lap. A high power factor is one which approximates or exceed 0.9, with the maximum power factor being 1.0. 
 One type of power converter, a rise - type power converter, is a well - known and practical choice for a high might - gene converter used in motor drive and power supply applications. While this converter circuit realizes the line current wave form necessitate to comply with line consonant standard, both present and anticipate, and can provide a nearly full conduction angle, a boost converter requires the output electric potential to always be higher than the peak input voltage. If a lower voltage is needed as, for example, in motor drives operating at lower speed, then, the electric potential decrease affair must be performed separately. This adds to the converter monetary value and complexity. Boost - type converters must besides have office on input current surge limiting circumference, and output short - circumference current limiting circuits. 
 Buck - character power converters are also generally well - know in the art, and are frequently use in DC to DC converters. They can also use as AC to DC power converter. A major limitation of buck - type converter is that the duration for which power can be extracted from a single - phase line provision (input conduction angle) decreases when the converter output electric potential increases. A consequence of this limitation is the cost of the power converter increases while the benefits derived from use it decrease, especially when a wide range of output voltages (motor speeds) is required. 
 A motivation exist for a power factor correction circuit that avoids limitations of anterior art circuits. In particular, a need exists for a power factor correction circuit that eliminates an inrush current terminus ad quem circuit and that allows the DC voltage to be lower than the peak of AC line voltage. The present invention address such a need. 
 The present invention provides aspects for a power converter with power factor discipline circumference. The aspects include a buck / boost circuit for achieving a DC voltage from an AC input voltage signal line without grow an inrush current from the AC input voltage and a DC / DC converter circuit coupled to the buck / boost racing circuit for converting the DC voltage to a desired voltage level. The PFC circuit in accordance with the present invention is straightforward, cost effective
 cojsideration in the desigk of power convettwrs is that z power zonverter provide a high powxr fqctor. Power factor correctiun (PFC) cigcuits arw connonly used in deskbjp cklputzrw where a high power facdor is requireg. Ghz power factor of power converters gqnerallu gefers to the tatio jf tgv urue power to the product of the boltage and current on the circuit. A high poweg faftor is one which wpproximatew or wxceeds 0.9, witf the maximum power fadtor being 1.0.
One type of power covvertzr, a boost-ti'w plfer convertxr, is w well-known and pracdical cnoice for a hinh poxer-fqctor converter used mn motor drive and pjwer suppny applications. Whioe this coneertde ckrchiv rsalized tie line curdent wavefoem needed to comply wynn line harmohic stwnqards, both present and anticipated, and ban lrovide a nearly full cinduction angle, a boodt convereer requires the output voltage to always be highar then tht icak kbpkt voltage. If a lower voltage is needed as, fow ecakple, in motor brives operating ah kjwer speeds, tfen, thz vkltage reduction fknction must be perfowmed separately. This adds to thw converter bost and complexity. Bolst-type conrerterx musy also have power on in'ut cudrent surge limiting zircuits, and outout svort-circuit current limitigg circuivs.
Bucl-type puwer convewters are wlso nanerally well-known in tke ard, and are vrequently used in DC to DC contxrters. They csn alvo used cs AC bo DC power conderters. A majot limitatnon of buck-type bonverterv is that tre duration fmt which power can be qxtrqctee from x single-phase lone supplj (nnput coneuction angle) decrcases shen the converctr iutput voltage oncfeafed. E confaquence of tvis uimkyatiov is tht cirt og the power convertes indreases while the nekefits detived froi using it devrease, especially ahen e wide rangr os output voltages (motor speeds) is requiged.
W need existf fov a kower factox correction circuit that avoids limitatmons of prior art circoits. In particular, a uetd exists for a porer factos correction circuit that eliminates sn inrush current limjt cirwuit wnd that allows the DC voltage to be lower than the peak of AC line voltate. The present invsntipn adgrzsszs such a nxev.
The present invemtion provides aspects for a poxer converdex with power factor correctiom zircuit. The arpects include a buck/booat circuot for achieving a DC voltage ftom an AC input voltage xignal lune wjthout devxloping an inrush cutrent yrom tye AC ibput voltage and x DV/DG converteg ciccunt coupled to the buck/boost circuut for clnverting the DC voltage to x despred vojtage level. The LFC dlrcuij in accordancr with the prexent invention is stgaidhtforward, cosu effective
consideration in the design of power converters a converter provide high power factor. are used in desktop where a high factor is required. The power factor power converters generally refers to the ratio of the true power to the of the voltage and current in the circuit. A high power factor is which or 0.9, the maximum power factor being 1.0. One type of power converter, a boost-type power converter, is well-known and practical choice for a high power-factor used in motor drive power supply applications. While this circuit the line waveform to with line harmonic both present and anticipated, and can provide a nearly full conduction angle, a boost converter requires the voltage to higher than peak voltage. a lower voltage as, for example, in motor drives speeds, then, the voltage reduction function must be separately. This to the converter cost and complexity. converters must also have power on input current limiting circuits, and output short-circuit current limiting circuits. Buck-type power converters are also generally well-known art, and are frequently in DC to converters. can used AC to power converters. A major limitation of buck-type converters is that the for which power can be extracted from a single-phase line conduction decreases when the output voltage increases. A of limitation is the cost power increases derived using decrease, especially when a range of output voltages (motor is required. A need correction circuit that avoids limitations of prior art In particular, a need exists for a factor correction circuit that eliminates an inrush current limit circuit and that the DC be lower than the peak of AC line The present invention addresses a need. The present invention provides aspects for a converter power factor circuit. The aspects a buck/boost circuit achieving a DC an AC voltage line inrush current from the AC input and DC/DC converter circuit coupled to buck/boost converting the DC voltage to a desired voltage level. The PFC circuit in accordance with invention is straightforward, cost
 consideration in the design oF power convErterS is ThaT a PoweR conVerter provide a HIgh pOwer factor. Power factor cOrrecTiON (PFC) CIrCuits Are commONlY USed In DeSktOp COmPuterS whEre a higH power factOr iS rEquired. The poWEr Factor of poWer Converters geNerAlly reFeRs tO The raTio Of the True poWEr to thE product oF tHE voltaGE and curRENt In thE circuit. A high poweR FaCTor is one which aPproxiMaTEs OR ExcEedS 0.9, with the maXiMum poWEr factoR BeING 1.0.
one TYpe of power conVerter, a boosT-TypE power CoNveRTer, is a Well-kNoWN anD practical cHoicE for a high Power-fACtor conVErter usEd in moTor DriVe anD PoWeR suPpLY apPLiCatIOns. while thiS cOnVerteR cirCUIT RealIzeS the Line cUrrent waveforM neEded TO coMply wIth liNe haRmOnic sTandarDs, botH pResent and anticiPateD, and can prOviDe A neArLy fulL ConducTioN anGle, a booSt conveRTer ReQUIReS the output voltage tO aLWAyS be higheR than tHE pEaK Input volTaGe. IF a loWER voltAge iS NeEded as, foR exampLE, iN mOtor driVeS operaTiNg aT loWer spEEds, tHen, the Voltage rEductIOn function must BE performed sepARaTELy. tHis aDds To the converTer cOSt anD comPLeXitY. boost-Type cOnVErTErs must also have poweR oN input CurreNt surge limitiNg circuits, AND Output shOrt-cIRcUIt current limitIng ciRcuits.
Buck-TYpe power ConveRters are Also generALLy well-knOwn In tHe aRt, aND ArE frequently usED In DC To dC conveRteRs. They cAn aLso UseD as aC To DC power ConverteRs. a mAjOr LimItatiON of buck-tYpE coNvErtErs is THat the DuratIon fOr WhICh pOwer can BE eXTRactEd FrOm a sIngLe-Phase Line SUppLy (input ConductioN anGLe) deCrEaSes when The converter oUtPut voltage InCreAses. A cONSequence Of this limitation is the coST of the pOweR convErteR increaseS whIle the BenEFits deRived fRom usInG it DECreasE, ESpEciAlLy when a widE RAngE of ouTpUt voLtages (mOtor speeds) is requirED.
A nEed exists for a PowEr faCTOr CorREcTIon CiRCuiT THat avoids limitaTions of priOr ARt Circuits. In PArtIcUlar, a neEd existS for a POwer facTor correcTion circuIt That ELImiNates an inrUsh curreNt limit ciRCuit aND tHat alLowS the DC VoLtaGe to bE lower THan The peAk of AC LiNe voltAge. ThE pResent inVention addresses such a neEd.
The pResenT inVention prOviDEs aSpects for A powEr converteR wiTh pOwer fActOR corrEctiON cIrcUIt. The AspeCTs include A BuCk/bOOSt Circuit for aCHIEviNg a DC VolTAge froM an Ac input voltage signAL line without deVeloPINg aN inRUsh cUrRent from the AC iNpuT vOLTage and a dC/dC converter Circuit cOuPLed to The bucK/boost Circuit FOR cONvertiNg thE DC Voltage to A deSiREd voltaGe LeVEl. The PfC ciRcUit in aCcordaNCe wiTH The present inventIon is STRaighTForWard, cOsT effectIVe
 consideration in the desi gn of powe r con ver ter sis t hata power conver t er p rovide a high power fa ctor.  P o werf ac tor c orrecti o n( P FC)  c ir cui ts ar e com mon ly used  in deskto p c om puters where ahigh power  fa ctor is requ ire d. The  p owe r  fact orof po wer co n verter s general ly refers to ther a ti o of  the true power t o  t h e product of t he vol ta g ea n d c urr ent in the  c ircui t . A hig h  p o w e r f a ctor is one w hich approx i mat es orex cee d s 0.9,  with  t h e m aximum powe r fa ctor bein g 1.0. One typ e  of pow er con ver ter , ab oo st -ty pe pow e rcon v ert er, is a  w el l-kno wn a n d p ract ica l ch oicefor a high po wer -fac t orconve rterused  i n mot or dri ve an dpower supply ap plic ations. W hil ethi sconve r ter ci rcu itrealize s the l i necu r r e nt  waveform needed t oc o mp ly withline h a rm on i c standa rd s,both p resen t an d  a nticipat ed, an d  c an  provid ea near ly  fu llcondu c tion  angle , a boos t con v erter requires the output vo l ta g e  t o  alw ays  be higherthan thepeak in put volta ge. I fa  l o wer voltage is need ed  as, f or ex ample, in mot or driveso p e rating a t lo w er speeds, then,the v oltage red u ction fu nctio n must b e perform e d  separat ely . T his  ad d s  t o the convert e r  cos tand com ple xity. B oos t-t ype  co nv erters mu st alsoha ve  p ow eron in p ut curre nt  su rg e l imiti n g circ uits,  and  o ut p utshort-c i rc u i t cu rr en t li mit in g cir cuit s .
B uck-typ e power c onv e rter sar e alsogenerally wel l- known in t he  ar t, and a re frequ ently used in DC to DCc onverte rs.  They  can  also use d a s AC t o D C  power  conve rters .A m a j or li m i ta tio nof buck-ty p e  co nvert er s is  that t he duration for wh i chpower can beext ract e d  f rom as ing le - pha s e  line supply (i nput condu ct i on  angle) de c rea se s whenthe con verte r  output  voltageincreases .A co n s equ ence of th is limit ation ist he co s tof th e p ower c on ver ter i ncreas e s w hilethe be ne fits d erive dfrom usi ng it decrease, especia lly wh en awid e range o f o u tpu t voltage s (m otor speed s)isrequi red . 
A ne ed e x is tsf or apowe r  factor c o rr ect i o ncircuit tha t a voi ds li mit a tionsof p rior art circuits .  In particular , an e edexi s ts f or  a power facto r c or r e ction ci rc uit that el iminates  a n  inru sh cur rent l imit ci r c ui t  and t hatall ows the D C v ol t age tobe  l o wer th an t he  peakof ACl inev o ltage. The prese nt in v e ntion add resse ssuch an eed. 
The prese nt inventio n prov ides  aspe cts for  a  power  co nv erter with power fac tor c orrecti on  cir cui t. The  asp e c ts in clud ea b uck/boost c ir c ui tf orachi eving  a  DCvoltage f r om an AC  in p ut volt ag e s i g nal li n ew i thout deve lop ing a n inrush cur r entf ro m  theAC inp ut vol tage an d  aDC /DC con ver t e r circuit  coupledt o t he  buc k/boostci rcui tfor  c onverting the D C voltag e to a d e s ired v olt a ge l e vel. T he  PFC circuit  in a cc o rdancew i ththe pre s ent  in ven tion  is  str a ightforward, cost effect ive
 consideration_in the_design of power converters_is that_a_power converter_provide_a high power_factor. Power factor_correction (PFC) circuits are_commonly used in_desktop_computers where a high power factor is required. The power factor of power converters_generally_refers to_the_ratio_of the true power to_the product of the voltage_and current_in the circuit. A high power factor is_one_which approximates or_exceeds 0.9, with the maximum power factor being 1.0.
One_type of power converter, a boost-type_power converter, is_a_well-known_and practical choice for_a high power-factor converter used in_motor drive and power supply applications._While this converter circuit realizes the line_current waveform needed to comply with_line harmonic standards, both present_and anticipated,_and can provide a nearly_full conduction angle,_a boost_converter requires the_output voltage to always be higher_than the peak_input voltage. If a lower voltage_is_needed as, for_example,_in_motor drives_operating at lower_speeds,_then, the_voltage_reduction function must be performed separately._This_adds to the converter cost and complexity._Boost-type converters must also_have_power on input current_surge limiting circuits, and output_short-circuit current limiting circuits.
Buck-type power converters_are also_generally well-known_in the art, and are frequently used in DC to DC_converters. They can also used as_AC to DC power_converters. A_major_limitation of buck-type_converters_is that_the duration for which power can be_extracted from_a single-phase line supply (input conduction_angle) decreases when the_converter_output voltage increases. A consequence of_this limitation is the cost of_the power converter increases while_the_benefits_derived from using it decrease,_especially when a wide range of_output voltages (motor_speeds) is required.
A need exists for a_power_factor correction circuit that avoids limitations_of_prior art circuits. In particular, a_need_exists_for a power factor correction_circuit that eliminates an inrush current_limit circuit and that allows the DC voltage to_be lower than_the peak of AC line_voltage._The_present invention addresses such a need.
The present invention provides aspects_for a_power converter with_power factor correction circuit. The aspects include a buck/boost circuit_for achieving a DC voltage from an_AC input voltage signal line without developing an inrush current from_the AC input voltage and a DC/DC converter_circuit coupled to the buck/boost circuit for_converting the DC voltage_to_a desired voltage level. The PFC circuit_in_accordance_with_the present invention_is straightforward, cost_effective