29-06-2013, 03:23 PM
Gas Insulated Switchgear (GIS)
Gas Insulated.pdf (Size: 1.66 MB / Downloads: 69)
Overview
New HV combined electrical equipment mainly includes:
①High-parameter, advanced SF6 circuit breaker; ②Digital
optoelectronic current/voltage transformer; ③Disconnecting
switch and earthing switch; ④ Local control, protection cabinet
There are 2 basic types according to different structures:
①Open type--Single-phase electrical equipment combined
by traditional SF6 circuit breaker, disconnecting switch,
earthing switch and new digital optoelectronic current/voltage
transformer, with the disconnecting switch and earthing switch
adopting air insulated structure; ②Metal enclosed type--Singlephase
electrical equipment combined by basic components
of GIS (Gas-insulated switchgear), including circuit breaker,
disconnecting switch, earthing switch, digital optoelectronic
current/voltage transformer, which are all enclosed in the metal
case and insulated by SF6.
Since SF6 has superior insulation performance, GIS can be
designed in compact structure, and several functions can be
integrated in one substation, which effectively reduces the floor
space. In general, GIS is applicable in small space and severe
environments. The highly reliable equipment with minimum
maintenance is often used in critical fields with higher power
supply requirements.
Main features
High technical performance
ZF36-126/T3150-40 type SF6 Gas Insulated Switchgear has
high technical performance with rated current reaching 3150A,
rated short-time withstand current of main circuit and earthing
circuit up to 40kA/4s and rated peak withstand current 100kA
respectively.
Circuit breaker of excellent performance
The circuit breaker adopts the most advanced self-energized
arc-extinguishing technology. Arc suppression can be done by
the energy of electric arc in the case of high breaking current. Its
full-capacity interrupting times are up to twenty times. Spring
mechanism is introduced as a result of low operation power.
It’s completely non-oil and air-free during operation. The circuit
breaker is maintenance-free and has a long life cycle.
Structure of proper design
Circuit breakers, connection combination and bus-bar adopt
full three-phase in one tank design. Due to their compactness
and standard bay width of only 0.8m, they could be transported
together to reduce the workload of installation and
commissioning on the site.
Circuit breaker operating mechanism is located in the upper
part of GIS in order to facilitate maintenance and inspection.
The height of the two main bus-bars is reduced, making onsite
installation easy. Transportation methods are diverse as the
height of each standard bay is only 2.8m.
The shell of GIS is made of aluminum alloy with good welding,
no eddy current loss, light weight and standard bay of only 4.5
tons. It adapts to the hot and wet climate of the south area so
that it won’t rust during the transportation.