Kawaradduka Bara Shugaban Karkashin Kirkiro
Idan da yake wani abu a cikin bus bars, kuma tana juye da kammal wannan mafi yawan tabbataccen kungiyar kasa. Akwai karshen masu iya zama na musamman da ke daidai. Abubuwan da ke gudanar da suka shafi da suna gudanar da bus zone faults sun haɗa da tsawon insulators, yanayin cutarwa a circuit breakers, ko abubuwa daban-daban da suka zama a cikin bus bars. Don haka, za a buƙaci duk circuits da suka shiga section da ke da fault.
Mafi girman bus zone protection schemes sun hada da:
Backup Protection for Bus - Bars
Backup protection yana nuna hanyar da yake da ita don inganta bus bars daga faults. Faults a cikin bus bar yana faruwar da supply system, saboda haka backup protection ya fi yawa a kan supply system. Taurari a nan ya bayyana setup na biyu na bus-bar protection. A nan, bus A an inganta ta hanyar distance protection mechanism ta bus B. Idan yake fault a bus A, device na ingantaccen ta bus B zai faɗi, a lokacin da relay ya yi aiki a baya da 0.4 seconds.
Idan a cikin bus bars yake wani abu, kuma tana juye da kammal wannan mafi yawan tabbataccen kungiyar kasa. Akwai karshen masu iya zama na musamman da ke daidai. Abubuwan da ke gudanar da suka shafi da suna gudanar da bus zone faults sun haɗa da tsawon insulators, yanayin cutarwa a circuit breakers, ko abubuwa daban-daban da suka zama a cikin bus bars. Don haka, za a buƙaci duk circuits da suka shiga section da ke da fault.
Mafi girman bus zone protection schemes sun hada da:
Backup Protection for Bus - Bars
Backup protection yana nuna hanyar da yake da ita don inganta bus bars daga faults. Faults a cikin bus bar yana faruwar da supply system, saboda haka backup protection ya fi yawa a kan supply system. Taurari a nan ya bayyana setup na biyu na bus-bar protection. A nan, bus A an inganta ta hanyar distance protection mechanism ta bus B. Idan yake fault a bus A, device na ingantaccen ta bus B zai faɗi, a lokacin da relay ya yi aiki a baya da 0.4 seconds.
Circulating Current Protection and Voltage Differential Protection Relay
Circulating Current Protection
A cikin hanyar circulating current protection, sum of currents ta current transformers (CTs) tana ɗauki a coil na relay. Idan current ta ɗauki a coils na relay, yana nuna cewa akwai short-circuit current a cikin CTs' secondaries. Saboda haka, relay tana bani signal zuwa circuit breakers, don haka suna ɗaukan contacts su da kuma isolar da section da ke da fault a cikin electrical system.
Amma, wani matsaloli na muhimmanci na wannan hanyar protection shine iron-cored current transformers zai iya buƙatar relay malfunctions a lokacin external faults. Muhimman magana na iron-cored CTs zai iya buƙatar unequal current transformation ratios a lokacin abunun gaba, wanda zai taimakawa relay zuwa false tripping.
Voltage Differential Protection Relay
Hanyar voltage differential protection relay yana amfani da coreless CTs, wadanda suke da linearity mai kyau da iron-cored counterparts. Linear couplers sun amfani a cikin hakan don sake ƙara number of turns a cikin secondary sides of these CTs, wanda yana sahihi sensitivity da accuracy na system na protection.
A cikin wannan setup, secondary relays suna ɗaukar da series via pilot wires. Kuma, coil na relay tana ɗauka da series da terminal na biyu ta relevant circuit. Wannan configuration tana ba ni aiki mai kyau wa comparison of electrical quantities, wanda yana ba protection system aiki mai kyau don tabbatar da internal faults, kuma yana ci gaba da abubuwan da ke buƙatar false operations a cikin hanyar traditional iron-cored CT-based schemes.
A cikin electrical system da ba da fault ko idan yake external fault, algebraic sum of the secondary currents of the current transformers (CTs) ce zero. Wannan balance tana nuna normal flow of current through the system's healthy components, with the CTs accurately reflecting the current distribution. Amma, idan yake internal fault a cikin protected zone, normal current flow tana rubuta. Fault current tana ɗauki a cikin differential relay, wanda tana rubuta balanced current state da aka sanya.
Idan differential relay ta tabbatar da abnormal current flow, tana faɗi. Tana bayyana command zuwa associated circuit breakers, don haka suka ɗaukan contacts. Ta haka, tana ci gaba da isolation da faulty section of the system, differential protection mechanism tana daidaita cutar da damage to equipment da kuma inganta stability of the overall electrical system. Wannan rapid response tana taimaka wajen minimize downtime da potential hazards, safeguarding the integrity of the power grid.
