Kev Xaiv Ntawm Kev Sib Hloov Hloov Rau Zero Sequence Tam Sim No Transformer

Zero sequence tam sim no transformers feem ntau siv me me transformation ratios vim hais tias lawv tsuas muaj tso zis thaum av txhaum tshwm sim ib zaug. Cov neeg yuav tsis qhib qhov kev tiv thaiv tsuas yog thaum lub hauv av tam sim no siab (tsis xav txog kev zam qhov tam sim no). Txawm li cas los xij, vim lub fact tias thawj winding yog lub hwj chim cable nrog tsuas yog ib tug tig, lub thib ob rated lem ntawm lub 50/5 xoom sequence tam sim no transformer tsuas yog 10 lem. Yog li ntawd, cov yam ntxwv load ntawm 50/5 xoom ib ntus tam sim no transformer tsis zoo. Thaum qhov tseeb load impedance tsis ua raws li lub peev xwm ntawm xoom sequence tam sim no transformer, yuav muaj qhov yuam kev tseem ceeb, thiab qhov yuam kev tseem yuav nce hauv qab qhov ntsuas tam sim no. Yog li ntawd, nws raug pom zoo kom xaiv qhov kev hloov pauv loj dua yog tias ua tau. Cov hauv qab no yog ib qho kev taw qhia txog kev xaiv ntawm kev hloov pauv rau xoom sequence tam sim no transformers hauv qee qhov tshwj xeeb.
1. Kev xaiv qhov sib txawv ntawm qhov sib txawv thaum twb muaj kev tiv thaiv tus nqi
Nrog kev tiv thaiv kev teeb tsa twb nyob rau hauv qhov chaw, nws yog ib qho yooj yim los xaiv qhov kev hloov pauv.
Yog tias tus nqi teeb tsa yog tam sim no ntawm 80A rau kev tiv thaiv, cov qauv kev ntseeg siab hauv lub tebchaws yuav tsum raug xaiv raws li 100/5 lossis 100/1.
2. Xaiv qhov kev hloov pauv hloov pauv rau qhov kev tiv thaiv hauv av
Lub grounding tam sim no ntawm qhov kev tiv thaiv hauv av muaj ob yam, ib qho yog lub peev xwm tam sim no thiab lwm qhov yog qhov nruab nrab ntawm qhov tsis kam tam sim no, nrog qhov sib txawv ntawm 90 degrees ntawm ob. Lub zero sequence tam sim no ntawm qhov txhaum Circuit Court yog sib npaug rau qhov sib txawv ntawm lub grounding point tam sim no thiab grounding capacitor tam sim no vector ntawm kab no, uas yog sib npaug rau qhov tsis zoo tus nqi ntawm cov sum ntawm lub grounding capacitor tam sim no thiab cov resistive tam sim no vector ntawm tag nrho cov. tsis txhaum kab. Piv txwv li: Resistance grounding system (IR=1-1.5IC).
Qhia xaiv qhov kev hloov pauv ntawm pes tsawg zaus tam sim no transformer: 50/1 100/1 150/1 200/1 100/5 200/5.
3. Kev xaiv xoom ib ntus tam sim no transformer piv rau nruab nrab point ungrounded thiab arc suppression coil grounded systems
Thaum lub hauv av tam sim no siab los yog qhov tsawg kawg nkaus pib tam sim no rau kev tiv thaiv yog tsawg, loj dua xoom kab ke tam sim no transformers nrog ntau dua transformation piv yuav raug xaiv, xws li 5{{20}}/1, 100/ 1, 100/5, 150/5 thiab siab dua. Txawm li cas los xij, qee qhov nruab nrab qhov nruab nrab qhov nruab nrab tsis siv neeg feem ntau tsis tso cai rau hauv av tam sim no tshaj 10A, yog li kev tiv thaiv yuav tsum tau qhib hauv qab 10A. Lub arc suppression coil grounding system feem ntau tsis muaj qhov tam sim no tshaj 10A vim qhov nruab nrab ntawm inductor tam sim no thiab capacitor tam sim no (feem ntau overcompensation, qhov tseeb grounding tam sim no twb inductor tam sim no). Vim yog kev siv cov kev tiv thaiv dav dav (qee zaum qhov siab xoom xoom ntu tam sim no transformers thiab lawv cov relays sib xws yog siv yam tsis muaj kev tiv thaiv, saib 2). Nws yuav tsum muaj qhov teeb tsa tus nqi, feem ntau Tsawg dua lossis sib npaug li 10A. Yog tias tus nqi teeb tsa muaj qhov tam sim no ntawm 5A, xav txog 100/5A lossis 20/1A. Thaum thawj qhov tam sim no yog 5A, qhov thib ob tam sim no yog 0.25A, uas feem ntau tshaj qhov pib tam sim no ntawm kev tiv thaiv dav. Yog tias qhov tsawg kawg pib tam sim no rau kev tiv thaiv kev tiv thaiv ntau dua 0.25A, ces 75/5, 50/5, 15/1, thiab 10/1 transformer ratios tsuas yog xaiv tau. Nws yog qhov zoo tshaj plaws los siv cov lej xoom ib ntus tam sim no transformers rau cov piv txwv no, txwv tsis pub qhov tseeb yuav qis dua.
4. Kev xaiv ntawm kev hloov pauv hloov pauv rau qhov siab tam sim no hauv av
Ib-theem ib-theem grounding system nrog ib qho nruab nrab point yog ib-theem luv luv Circuit Court. Qhov kev hloov pauv tuaj yeem raug xaiv kom loj dua, xws li 150/5, 150/1 lossis siab dua, tsis yog me me, txwv tsis pub muaj qhov sib npaug tam sim no tsis tuaj yeem zam. Thov nco ntsoov tias txoj kab nruab nrab (N) yuav tsum tsis txhob hla CT.