Todobaadkan waxaan sii wadeynaa maqaalkii usbuucii hore.

1.2 Qalabka korantada (electrolytic capacitors).

Dielectric-ka loo isticmaalo capacitors electrolytic waa aluminium oxide ka samaysan daxalka aluminium, oo leh dielectric joogto ah 8 ilaa 8.5 iyo xoog dielectric shaqeeya oo ku saabsan 0.07V/A (1µm=10000A).Si kastaba ha ahaatee, suurtagal maaha in la gaaro dhumucdan oo kale.Dhumucda lakabka aluminiumku waxay yaraynaysaa awoodda awoodda (capacitance gaarka ah) ee korantada korantada sababtoo ah aluminium aluminiumku waa in la dhajiyaa si loo sameeyo filim aluminium ah oo oksijiin ah si loo helo sifooyinka kaydinta tamarta wanaagsan, dushana waxay samayn doontaa meelo badan oo aan sinnayn.Dhanka kale, iska caabinta elektrolytka waa 150Ωcm danab hooseeya iyo 5kΩcm danab sare (500V).Iska caabbinta sare ee elektrolytka ayaa xaddidaysa hadda RMS ee kapacitor-ku uu u adkeysan karo, sida caadiga ah ilaa 20mA/µF.

Sababahan dartood capacitors electrolytic waxaa loogu talagalay danab ugu badnaan 450V caadiga ah (qaar ka mid ah saarayaasha shakhsi design 600V).Sidaa darteed, si loo helo koronto sare waxaa lagama maarmaan ah in lagu gaaro iyaga oo isku xiraya capacitors si taxane ah.Si kastaba ha ahaatee, sababtoo ah kala duwanaanshaha caabbinta dahaarka ee capacitor kasta oo elektrolytic ah, resistor waa in lagu xidhaa capacitor kasta si loo dheelitiro danab kasta capacitor ku xiran yahay.Intaa waxaa dheer, capacitors electrolytic waa qalab polarized, iyo marka danab gadaashiis codsatay ka badan 1.5 jeer Un, falcelin electrochemic ah ayaa dhacaya.Marka danabka gadaale ee la dabaqay uu dheer yahay, capacitor-ku wuu daadan doonaa.Si looga fogaado dhacdadan, diode waa in lagu xiro capacitor kasta agtiisa marka la isticmaalayo.Ka sokow, iska caabinta korantada ee korantada korantada guud ahaan waa 1.15 jeer Un, kuwa wanaagsanna waxay gaari karaan 1.2 jeer Un.Markaa naqshadeeyayaashu waa inay tixgeliyaan ma aha oo kaliya korantada shaqada ee joogtada ah laakiin sidoo kale korantada kor u kaca marka la isticmaalayo.Marka la soo koobo, shaxda isbarbardhigga ee soo socota ee u dhaxaysa capacitors film iyo capacitors electrolytic waa la sawiri karaa, eeg Fig.1.

2. Falanqaynta Codsiga

Dc-Link capacitors sida filtarrada waxay u baahan yihiin nashqadaha awoodda hadda sare leh iyo kuwa sare.Tusaale ahaan waa habka ugu muhiimsan ee wadista baabuurta tamarta cusub sida ku xusan shaxanka 3.Codsigan capacitor-ku waxa uu ka ciyaaraa door kala furfurid iyo wareeggu waxa uu leeyahay awood hawleed saraysa.Capacitor-ka filimka DC-Link wuxuu leeyahay faa'iido u leh inuu u adkaysto qulqulka hawlgelinta waaweyn (Irms).Qaado 50 ~ 60kW cabbirrada baabuurta tamarta cusub tusaale ahaan, halbeegyadu waa sida soo socota: Voltage shaqeynaya 330 Vdc, Voltage 10Vrms, ripple current 150Arms@10KHz.

Markaa awoodda korantada ugu yar ayaa loo xisaabiyaa sida:

Tani way fududahay in la hirgeliyo naqshadaynta capacitor filimka.Iyadoo loo malaynayo in capacitors electrolytic la isticmaalo, haddii 20mA/μF la tixgeliyo, awoodda ugu yar ee korantada korantada ayaa loo xisaabiyaa si ay u buuxiso xuduudaha kor ku xusan sida soo socota:

Tani waxay u baahan tahay kapacitors badan oo elektrolytic ah oo isku mid ah oo ku xiran si loo helo awooddan.

Codsiyada koronto-dhaafka ah, sida tareenada fudud, baska korontada, tareenada dhulka hoostiisa mara, iwm. Iyadoo la tixgelinayo in awoodahani ay ku xiran yihiin pantograph-ka loo yaqaan 'pantograph', xiriirka ka dhexeeya pantograph iyo pantograph waa kala go'a inta lagu jiro safarka gaadiidka.Marka labadoodu aanay xidhiidhin, sahayda korontadu waxa taageeraysa capacitor khad DC-L, iyo marka xidhiidhka dib loo soo celiyo, koronto-dhaafka ah ayaa soo baxaya.Xaaladda ugu xun waa dareere dhammaystiran oo ka yimaada korantada DC-Link marka la gooyo, halkaas oo korantada sii deyntu ay la mid tahay korantada pantograph, iyo marka xiriirka dib loo soo celiyo, natiijada korontadu waxay ku dhowdahay laba jeer heerka hawlgalka Un.Capacitors-ka filimada capacitor-ka DC-Link waa la maarayn karaa iyada oo aan tixgelin dheeraad ah la siin.Haddii capacitors electrolytic la isticmaalo, koronto-dhaafka ah waa 1.2Un.Tusaale ahaan u soo qaad metro Shanghai.Un=1500Vdc, loogu talagalay korantada korantada si loo tixgeliyo danabku waa:

Kadibna lixda 450V capacitors waa in si taxane ah loogu xidhaa.Haddii naqshadda capacitor-ka filimka loo isticmaalo 600Vdc ilaa 2000Vdc ama xitaa 3000Vdc si fudud ayaa loo gaari karaa.Intaa waxaa dheer, tamarta in kiiska si buuxda u daayo capacitor foomamka dheecaan wareegga gaaban dhexeeya labada electrodes, dhalinaya faleebo weyn hadda iyada oo loo marayo capacitor DC-Link, kaas oo inta badan ka duwan capacitors electrolytic si ay u buuxiyaan shuruudaha.

Intaa waxaa dheer, marka la barbardhigo capacitors electrolytic capacitors DC-Link film capacitors waxaa loo qaabeyn karaa si loo gaaro ESR aad u hooseeya (sida caadiga ah ka hooseeya 10mΩ, iyo xitaa hoose <1mΩ) iyo is-inductance LS (sida caadiga ah ka hooseeya 100nH, iyo xaaladaha qaarkood ka hooseeya 10 ama 20nH) .Tani waxay u ogolaaneysaa in DC-Link capacitor filimka si toos ah loogu rakibo moduleka IGBT marka la codsado, taas oo u oggolaanaysa baska in lagu daro capacitor filimka DC-Link, taas oo meesha ka saaraysa baahida loo qabo qalabka IGBT ee u go'an marka la isticmaalayo capacitors filimada, badbaadinta naqshadeeyaha lacag aad u badan.Jaantuska.2.iyo 3 waxay muujinayaan tilmaamo farsamo ee qaar ka mid ah alaabta C3A iyo C3B.

3. Gabagabo

Maalmihii hore, DC-Link capacitors inta badan waxay ahaayeen capacitors elektrolytic sababtoo ah qiimaha iyo tixgelinta cabbirka.

Si kastaba ha ahaatee, capacitors electrolytic waxaa saameeya danab iyo awood u adkeysiga hadda (ESR aad u sarreeya marka la barbar dhigo capacitors film), sidaas darteed waxaa lagama maarmaan ah in la isku xiro dhowr capacitors electrolytic si taxane ah oo barbar socda si ay u helaan awood weyn iyo buuxiyo shuruudaha isticmaalka danab sare.Intaa waxaa dheer, iyada oo la tixgelinayo isbeddelka walxaha elektrolytka, waa in si joogto ah loo beddelaa.Codsiyada tamarta cusub guud ahaan waxay u baahan yihiin nolosha badeecada 15 sano, markaa waa in la beddelaa 2 ilaa 3 jeer inta lagu jiro muddadan.Sidaa darteed, waxaa jira kharash badan iyo dhib la'aan adeegga iibka ka dib ee mashiinka oo dhan.Horumarinta tikniyoolajiyadda daahan birta ah iyo teknoolojiyadda capacitor filimka, waxaa suurtagal ah in la soo saaro awood sare oo awood leh oo shaandhada DC ah oo leh danab laga bilaabo 450V ilaa 1200V ama xitaa ka sarreeya filimka aadka u khafiifka ah ee OPP (2.7µm ugu khafiifsan, xitaa 2.4µm) iyadoo la adeegsanayo tignoolajiyada uumiga filimka badbaadada.Dhanka kale, isku dhafka DC-Link capacitors ee baska baska ayaa ka dhigaya naqshadeynta moduleka rogaha si aad u adag oo si weyn u yareysa qulqulka qulqulka wareegga si loo hagaajiyo wareegga.