Kupararira kwesimba remagetsi mumagetsi eAC kwakafanana, uye chinangwa chezvinhu zvinodzivirira tambo ndechekuisa dielectric constant, iyo isingakanganiswi nekupisa. Kusiyana neizvi, kupararira kwesimba mumagetsi eDC kwakakwira padanho remukati rekudzivirira uye kunokonzerwa nekudzivirira kwechinhu chinodzivirira. Zvinhu zvinodzivirira tambo zvinoratidza temperature coefficient yekupisa isina kunaka, zvichireva kuti sezvo tembiricha ichiwedzera, kudzivirira kunoderera.
Kana tambo iri kushanda, kurasikirwa kwepakati kunokonzera kuti tembiricha ikwire, zvichikonzera shanduko mukusimba kwechinhu chinodziisa. Izvi, zvinoita kuti kushushikana kwemagetsi mukati mechikamu chinodziisa kushanduke. Nemamwe mashoko, nekuda kweukobvu hwakafanana hwechinhu chinodziisa, voltage yekupwanyika inoderera sezvo tembiricha ichikwira. Kune DC trunk lines munzvimbo dzemagetsi dzakapararira, mwero wekukwegura kwechinhu chinodziisa unokurumidza zvikuru nekuda kwekuchinja-chinja kwetembiricha yemhepo zvichienzaniswa netambo dzakavigwa, inova pfungwa yakakosha yekucherechedza.
Munguva yekugadzira tambo dzinodzivirira kusvibiswa, tsvina inoiswa. Tsvina idzi dzine resistivity yakaderera yekudzivirira kusvibiswa uye dzinopararira zvisina kuenzana munzira ye radial ye insulation layer. Izvi zvinoguma nekusiyana kwe volume resistivity munzvimbo dzakasiyana. Pasi pe DC voltage, simba remagetsi riri mukati me insulation layer richasiyanawo, zvichiita kuti nzvimbo dzine resistivity yakaderera yevhoriyamu dzikurumidze kukura uye dzive nzvimbo dzinogona kukundikana.
Tambo dzeAC hadziratidzi izvi. Nemashoko akareruka, kushushikana kwezvinhu zveAC cable kunogoverwa zvakaenzana, nepo muDC cables, kushushikana kwekudzivirira kunogara kwakatarisana nenzvimbo dzisina kusimba. Nokudaro, maitiro ekugadzira uye mwero wetambo dzeAC neDC dzinofanira kutarisirwa zvakasiyana.
Polyethylene yakabatana nemuchinjikwa (XLPE)Tambo dzakadzivirirwa dzinoshandiswa zvakanyanya muAC nekuda kwehunhu hwadzo hwakanaka hwe dielectric uye physical, pamwe ne cost-performance ratio yadzo yepamusoro. Zvisinei, kana dzichishandiswa se DC cables, dzinosangana nedambudziko guru rine chekuita nekuchaja kwenzvimbo, izvo zvinonyanya kukosha mu DC cables dzine voltage yakawanda. Kana ma polymers achishandiswa se DC cable insulation, nhamba yakawanda ye localized traps mukati me insulation layer inokonzera kuunganidzwa kwe space charges. Mhedzisiro ye space charges pazvinhu zve insulation inonyanya kuratidzwa muzvikamu zviviri: electric field distortion uye non-electrical field distortion effects, zvese izvi zvinokanganisa zvakanyanya insulation material.
Kuchaja kwenzvimbo kunoreva kuchaja kwakawandisa kunopfuura kusapindirana kwemagetsi mukati meyuniti yechimiro chezvinhu zvikuru. Muzvinhu zvakasimba, kuchaja kwenzvimbo kwakanaka kana kusina kunaka kunosungirwa kumazinga esimba ari munzvimbo, zvichipa mhedzisiro yepolarization muchimiro chebound polarons. Kuchaja kwenzvimbo kwakanaka kunoitika kana ma free ions aripo mune dielectric material. Nekuda kwekufamba kwemaion, ma negative ions anoungana panzvimbo iri pedyo ne positive electrode, uye ma positive ions anoungana panzvimbo iri pedyo ne negative electrode. Mu AC electric field, kufamba kwe positive ne negative charges hakugone kuenderana nekuchinja nekukurumidza mumunda wemagetsi we power frequency, saka mhedzisiro ye space charge haiitike. Mumunda wemagetsi weDC, zvisinei, munda wemagetsi unopararira zvichienderana ne resistivity, zvichitungamira pakuumbwa kwe space charges uye kukanganisa kugoverwa kwemunda wemagetsi. XLPE insulation ine huwandu hwakawanda hwenzvimbo dziri munzvimbo, zvichiita kuti mhedzisiro ye space charge ive yakanyanya kuipa.
Kudzivirira kweXLPE kwakabatana nemakemikari, zvichigadzira chimiro chakabatana. Sepolymer isiri polar, tambo pachayo inogona kufananidzwa necapacitor hombe. Kana DC transmission yamira, zvakafanana nekuchaja capacitor. Kunyangwe core yeconductor iri pasi, kuburitsa simba hakuitiki, zvichisiya simba rakawanda reDC rakachengetwa mutambo sechaja dzemuchadenga. Kusiyana netambo dzemagetsi dzeAC, uko chaja dzemuchadenga dzinopararira kuburikidza nekurasikirwa kwe dielectric, chaja idzi dzinoungana kana tambo dzakanganisa.
Nekufamba kwenguva, nekukanganiswa kwesimba remagetsi kakawanda kana kuchinja-chinja kwesimba remagetsi, tambo dzeXLPE dzakadzivirirwa dzinowedzera kubhadharisa nzvimbo, zvichiita kuti kuchembera kwechikamu chekudzivirira kupisa kuwedzere uye kuderedza hupenyu hwebasa retambo.
Nguva yekutumira: Kurume-10-2025