Ninaitwa Oliver, mtaalamu wa kutest kwa transformer za current kwa miaka minne. Leo, hebu tufafanulie njia mpya na zamani za kutest polarity kwa GIS current transformers—jinsi zinavyofanya kazi na faida na madhara yao.
1.Njia za Kutest
1.1Njia Mpya
Ufundi kabla ya kutest: Fungua FDS21/FDS22 disconnectors wa haraka + DS23 disconnector. Funga CB21 breaker, basi ES21/ES22 grounding disconnectors. Tengua ground ya SF6-shell ya ES21.
Umeme: Unganisha battery kati ya contact inayozunguka (negative grounded) ya ES21 + ground electrode. Hii itawezesha umeme kuenda L1→L2 katika primary coil ya TA. Unganisha K1 (CT secondary) kwa DC milliammeter +ve, K2 kwa -ve.
Test: Tumia njia ya DC—elekea DC kwenye primary, angalia deflection ya milliammeter. Tumia range ≤100mA (100μA ni bora kwa deflection safi). Unganisha/vutia kwa ujumla contact inayozunguka ya ES21 + K - battery +ve. Deflection chanya (battery imewekwa) + hasi (battery imevutiwa) inamaanisha L1 (CT) na K1 (secondary) ni sawa polarity. Jaza maeneo ya CT primary coil; piga matokeo.
1.2 Njia Zamani
Ufundi kabla ya kutest: Funga FDS21/FDS22 disconnector, disconnector uliyopatana. Fungua ES21/ES22 grounding disconnectors. Funga CB21 breaker.
Umeme: Unganisha battery +ve kwenye 110kV inlet bushing (Ⅰ/Ⅱ), -ve kwenye GIS outlet bushing. Unganisha/vutia kwa ujumla. Deflection chanya (imefunika) + hasi (imefungwa) inamaanisha L1/K1 ni sawa polarity. Jaza maeneo ya CT; piga matokeo.

2 Ulinganisho wa Njia
Mpya: Umeme rahisi/ufundi, upungufu wa nishati chache, inaweza kutumika na batilinya ndogo. Milliammeter hutikisa kwa nguvu—sensitivity chanya, sahihi.
Zamani: Hatua ngumu, mizizi mrefu—matatizo mahali pa kutest. Hazards za juu (umeme wa batilinya kwenye bushings). Vifaa vya series vigumu → impedance chanya → matokeo isiyostahimili. Mara nyingi huchukua batilinya kubwa (zuri sana mahali pa kutest), kusababisha majibu machafu.
3. Matumizi Yanayohitajika kwa Usalama
Fuatilia sequence gani: Weka CB21 wazi → fungua FDS21/FDS22 (line) + DS23 (bus) → funge ES21/ES22 (grounding). Muhimu kwa mitindo ya umeme/buses—kuzuia ajali za “live + ground disconnector”.
4. Mwisho
Njia mpya inatibisha matatizo ya kutest polarity mahali pa kutest, husaidia relay protection ikisafiri, na kukabiliana na grid. Baada ya miaka minne katika kutest, ninashuhudia: kutagua njia sahihi inabalance usalama + ukurasa.