Me ke gini GIS (Gas-Insulated Switchgear)? Abubuwa Daban-Daban Types da Applications
Zai da ne GIS Equipment?
GIS ita ce tushen Gas Insulated Switchgear, wanda a yi karshe a Turanci na Gas-Insulated Metal-Enclosed Switchgear. Yana amfani da gas sulfur hexafluoride (SF6) a matsayin mafi girgizarwa da kuma mafi girgizarwancin hankali. GIS ta gudanar da, tun daga tushen babbar masu sayarwa a substation—kafin bayan aikace-ta—kamar circuit breakers (CB), disconnectors (DS), earthing switches (ES/FES), busbars (BUS), current transformers (CT), voltage transformers (VT), surge arresters (LA), cable terminations, da kuma incoming/outgoing line bushings—a cikin wurin zane mai kyau, ta haɗa sararin yadda ake ƙunshi.
Yanzu, mutane da suka samu GIS equipment suna da tsari daban-daban, to jin da 72.5 kV zuwa 1200 kV.
Abubuwan da suka bi GIS Equipment
Gas SF6 tana da kyakkyawan mafi girgizarwa, mafi girgizarwancin hankali, da kuma kyakkyawan kimiyar. Saboda haka, GIS equipment tana da tsari mai kusa, kadan mai kusa, inganci mai fiye, lokacin da aka kare mai kusa, da kuma kyakkyawan mafi girgizarwa ga abubuwan da suka fito a kan electromagnetic interference. Da kuma saboda wurin da ke mai kyau, abubuwan da suke cikin su ne da su iya magance waɗannan abubuwan da ke kan al'adu (kamar dust, moisture, da salt fog), wanda ya ba su karfin rike, kadan mai kusa, da kuma kare mai kusa.
Amma, mafi girgizarwar da ake amfani da shi a kan SF6 gas tana da kyakkyawan mafi girgizarwa ga electric field uniformity. Abubuwan da suka bi da a cikin su kamar burrs, metallic particles, ko flaws, za su iya magance partial discharge ko kuma insulation breakdown. Kuma, saboda wurin da ke mai kyau na GIS, diagnosis da kuma kare mai kusa a cikin su zai iya zama mafi kyau, domin abubuwan da ake amfani da su a kan diagnostic tools suka bi da muhimmanci. Kyakkyawan mafi girgizarwa na water ingress ko kuma gas leakage, tana iya haifar da darajar da suka bi da su a kan safety na equipment.
Abubuwan Electrical Contacts a GIS Conduction Circuits
Conduction circuit a GIS tana da abubuwan da suka bi, da za su iya haɗa da su a kan tsari uku:
Fixed Contact: Electrical connections secured by bolts or other fasteners, with no relative movement during operation, such as the connection between a busbar and a basin-type insulator.
Separable Contact: Electrical contacts that can be opened or closed during operation, such as the contacts in circuit breakers and disconnectors.
Sliding or Rolling Contact: Contacts that allow relative sliding or rolling between contact surfaces but cannot be separated, such as intermediate contacts in switchgear.
Bayanin HGIS
Kafin da GIS, akwai wata kawai na HGIS (Hybrid Gas-Insulated Switchgear), wanda ake kira hybrid gas-insulated switchgear. HGIS ba tana da abubuwan kamar busbars, busbar voltage transformers, ko busbar surge arresters, wanda ya ba su karfin tsari mai kusa. Ita ce da ita da kyakkyawan mafi girgizarwa a wurare da take sauraro ko kuma wurare da take saukar da space, da kuma ita da kyakkyawan mafi girgizarwa ga layout.
Classification of GIS Equipment
By Installation Location: Indoor and outdoor types.
By Structure: Single-phase single-enclosure and three-phase common-enclosure. Generally, busbars at voltage levels of 110 kV and below can adopt the three-phase common-enclosure design, while voltage levels of 220 kV and above typically use the single-phase single-enclosure design to reduce the risk of phase-to-phase faults.
Basic Operating Principles
Under normal conditions, GIS circuit breakers and disconnectors are primarily operated remotely. The "Remote/Local" selector switch should be set to the "Remote" position.
Earthing switches can only be operated locally. During operation, the "Disconnector/Earthing Switch" selector switch must be switched to the "Local" position.
All operations must follow programmed procedures. The "Interlock Release Switch" on the control cabinet must remain in the "Interlock" position. The unlocking key, along with the microcomputer anti-misoperation unlocking key, must be sealed and managed strictly according to regulations.
Basic Operational Requirements
For indoor SF6 equipment rooms frequently accessed by personnel, ventilation should be performed at least once per shift for no less than 15 minutes, with air exchange volume exceeding 3–5 times the room volume. Air exhaust outlets should be located at the lower part of the room. For areas not frequently entered, ventilation for 15 minutes is required before entry.
During operation, the induced voltage on accessible parts of the GIS enclosure and structure should not exceed 36 V under normal conditions.
Temperature Rise Limits:
Easily accessible parts: no more than 30 K;
Parts easily touched but not contacted during operation: no more than 40 K;
Rarely accessible individual parts: no more than 65 K.
SF6 switchgear should be inspected at least once daily. For unattended substations, inspections should be conducted according to established procedures. Inspections should focus on visual checks for abnormalities such as unusual sounds, leaks, or abnormal indications, with records maintained accordingly.
