The calculation of the characteristic and non-characteristic harmonic current of the rectifying system

Transcription

1 The calculato of the chaactestc a o-chaactestc hamoc cuet of the ectfyg system Zhag Ruhua, u Shagag, a Luguag, u Zhegguo The sttute of Electcal Egeeg, Chese Acaemy of Sceces, ejg, 00080, Cha. Zhag Ruhua, Telephoe: , E-mal: uhuazh@mal.ee.ac.c, a Luguag, Telephoe: , E-mal: lgya@mal.ee.ac.c, u Shagag, E-mal: shgu@mal.ee.ac.c, u Zhegguo, E-mal: zhgu@mal.ee.ac.c.eywos: Rectfyg System, Chaactestc Hamoc, o-chaactestc Hamoc Abstact The pape aalyzes the easos fo poucg o-chaactestc hamocs ectfyg system. Some fomulas fo hamoc cuet calculato ae eve. The theoetcal a calculatve fouatos fo flte esg ae pove, we ca see that we shoul pay atteto to the o-chaactestc hamoc cuet eve f we use -pulse covete. Topc: 4 touce ecause of the electc electo evce s use the powe system, the hamoc s becomg moe a moe heavly, the maglev system, t s covete that supply powe to the vehcle to ajust the spee of the vehcle, the covete wll ceate hamoc cuet to the powe supply system clug chaactestc hamoc a o-chaactestc hamoc, oe to stall flte to euce the hamoc level, we shoul calculate the hamoc cuet of the covete. Chaactestc hamoc calculato oe to euce the hamoc cuet, may case, the covete s -pulse, ts schematc s show fgue [, theoy, t ca cotacts th hamoc cuet a 7th hamoc cuet, the th a th hamoc cuet ae ts chaactestc hamoc cuet We suppose the electcal souce s balaceable as flows: ea Em s a eb Em s a ec Em s a The the le cuet of bge the powe system se s: s s s7 s s L 7 446

2 A C 4 g. The schematc agam of the covete The le cuet of bge the powe system se s: s s s7 s s L 7 all the jot cuet of two cotolle bges the powe system se s: So 4 c s s s L The jot cuet of two o-cotolle bges powe system se s: uc 4 s α s α s α L The total cuet powe system se s: 4 cos80 a o-chaactestc hamoc calculato fact, the covete ca ot cotacte all the th a 7th hamoc cuet completly because of the tasfome ato whch ca lea to the ubalace voltage s ot balace, th a 7th hamoc cuet ae calle o-chaactestc hamoc a -pulse ectfes, may case, the o-chaactestc wll be so hgh that th a 7th flte wll be eee to esue the hamoc level. Thee ae two easos that lea to the o-chaactestc hamoc the ectfyg system, oe s the ubalace of the loa betwee two ectfe bges, the othe s the phase coveso pocess. 447

3 448. The fluece of the loa ubalace betwee two ectfe bges o the o-chaactestc hamoc cuet A a U o U o g. the equvalet agam of two paallel ectfe bges g s the equvalet agam of two paallel ectfe bges, fom ths agam we ca see: ths fomula, s the covet coeffcet of the eactace, 6 0. s the umbe of -coecte wgs a the umbe of coecte wgs. The ubalace cuet betwee two bges s : s The hamoc cuet cause by the ubalace loa cuet s as follows: s9 9 s 7 s7 7 s s L 6 ±,,, the most sevee stuato, So the ampltue ato of o-chaactestc hamoc cuet a the fuametal cuet s:

4 l ma. The fluece of phase coveso o the o-chaactestc hamoc cuet ealty, whe ectfe system s opeato, because of the eactace, the le cuet s ot ectagula wavefom but tapezoal wavefom The phase coveso pocess shoul meet the followg equato:. c a L eac L t t eac Em s a s a a c c 0 To solve ths equato, we ca get: the fomula, a c cos a cos a s the eactace AC se, ω L cos γ γ s the ovelappg agle phase coveso. The epesso of the cuet AC se ca be epesete table. Table. the epesso of the cuet AC se, ω t a 0 ω t < γ [ cos a cos a γ ωt < cos γ a ωt < γ cos a cos γ a γ ωt < 0 To oue aalyss the epesso of the cuet, we ca get the epesso of the effectve value of fuametal cuet a all the hamoc cuet. 449

5 6 [ [ s s cos s s cos α a E cosα cos α E s s s s cos a 6±,,,, o o-chaactestc hamoc cuet, the phase-agle ffeece of a s 80 0,so A E E the fomula,, 7, 7, 9 A s s s s cos a 4 Cocluso The pape aalyzes the easos fo poucg o-chaactestc hamocs ectfyg system. Some fomulas fo hamoc cuet ae eve. The theoetcal a calculatve fouatos fo amsteg hamoc ae pove. om ths pape, we ca see that the flte shoul be stalle the substato to euce the hamoc cuet. ase o a moel of powe supply system of the Maglev to smulate the stbuto of hamoc cuet, the hamoc cuet of the Maglev ffeet stuatos s calculate. The easos fo poucg o-chaactestc hamocs ectfyg system ae aalyze. Some fomulas fo hamoc cuet calculato ae eve. Eve f we use -pulse covete, we shoul calculate that th a 7th hamoc cuet a stall appopate flte system to mae sue that the powe level meet the hamoc staa. REERECE: [ Zhag Ruhua, u Shagag, a Luguag, u Zhegguo, Optmal Desg of ltes the Powe Supply System of Maglev, maglev004 cofeece, , Shagha, Cha [Wu agmg, Maglev ta, Shagha Scece a Techology Publshg House, 00. [ Wag Zhaoa, Hamoc lmtg a eactve powe compesato, Cha Mache Pess, 00. [4 a Luguag. Cha ees Hgh-Spee Magetcally Levtate Ta. Chese Egeeg Scece, Vol., o., May 000, pp. 8-. [ Huag Dahua, e Lsheg, o selecto of stuctue type of ectfome fo use -pusle ectfe, powe souce a ts applcato,