Yüksek gerilim teçhizatlarında dış etken kaynaklı arızaların analizi ve azaltılması
Öz
Bu çalışmada, yüksek gerilim güç sistemlerinde arızaların en çok yaşandığı teçhizatlar olan izolatörler ve
porselen dış yüzeye sahip şalt ekipmanları incelenmiştir. Bu teçhizatlarda arızalara neden olan dış ortam
etkileri belirlenmiştir.
Dış ortam etkilerinin teçhizatlar üzerinde meydana getirdiği arızalar aşama aşama incelenmiştir. Kirlilik
etmenlerinin ortamın nemli ve yağışlı yapısıyla birleşerek izolatör yüzeylerinde yüzey kaçak akımları
oluşturduğu, oluşan kaçak akımların kuru band bölgelerini meydana getirdiği bilinmektedir. İzolatör
yüzeyinde oluşan kısmi arkların tüm yüzeye yayılarak atlamaya neden olması sonucu izolatörde deformasyon
oluştuğu saptanmıştır. Bu arızaların sonucunda elektrik kesintileri ve maddi kayıplar oluşmaktadır.
Bu çalışmada, meydana gelen bu arızaların azaltılması için porselen izolatörlerin silikon kaplama
materyalleriyle kaplanması ya da silikon izolatörlerle değiştirilmesi gerekliliği ortaya konulmuştur. Yüksek
gerilim şalt ekipmanlarının da silikon kaplamayla kaplanması gerekmektedir. Bu yöntem ile porselen
izolatörlerin hidrofobikliğinin arttırılması ve bu sayede yüzey kaçak akımlarının bastırılması amaçlanmıştır.
Anahtar Kelimeler
Analysis and mitigation of external factors induced failures in high voltage equipment
Abstract
In this study, insulators and switchyard equipment
with porcelain outer surface with the most
experienced equipment failures in high voltage
power systems have been investigated. The effects of
the external environment cause malfunctions in
these equipments are determined.
Due to the external environment effects failures
occurring in equipment were examined. Firstly,
high-voltage switchgear equipments which are the
subject of study are explained. These include circuit
breakers, disconnectors, current transformers,
voltage transformers, surge arresters and insulators,
which have porcelain outer surface are counted.
External environment pollution which is exposure of
these devices is determined. Beach and industrial
dirt, the dirt is separated into two parts. How caused
pollution effects and dry dirt layer on the insulator
surface by pollution factors explained. Then it was
determined, the dry dirt layer combined with the
moist and rainy environment, creates surface
leakage current on insulator surface and leakage
current is forming a dry band arcs. After, on the
entire surface has been found to occur in the
insulator deformation with seen flashover. As a
result of these failures it was determined that the
formation of power outages and financial loss.
Different methods to reduce these defects occurring
have been proposed. These include porcelain
surface periodic manual cleaning, cleaning with
abrasive spray, washing with water, heating the
insulator surface, design changes, use surface
covering materials. The most effective among these
methods the porcelain surface is coated with the
silicone coating material. Also, porcelain insulators
to be replaced with silicon insulators necessity were
laid. The surface coating material impact and
implementation are described. With this method the
surface of the porcelain insulator to increase the
hydrophobicity and whereby the surface leakage
currents was intended the suppression.
In order to emphasize the benefits of the proposed
method within the scope of this article, operating
within the Turkey national electricity transmission
system in the Kaş district of Antalya province TEIAŞ
154 / 31.5 kV Kaş substation and 154 kV Kaş-
Fethiye power transmission lines was investigated.
Kaş substation switchgear equipment (circuit
breakers, disconnectors, current transformers,
voltage transformers, surge arresters, insulators)
coated with a silicone coating material in june in
2011 year and Kaş-Fethiye 154 kV power
transmission line porcelain insulators were replaced
with silicon insulators in the same year. The power
of transformer center which selected 50 MVA. The
length of the transmission line 82 km and conductor
grade 477 MCM. Number of 154 kV line failures
when before and after the maintenance works
occurring has been compared with 48 in 2010, the
work was completed in 2011 which fell to 5, the
number of failures has been determined to occur
among 3 to 5 in subsequent years. If additional table
1 and additional table 2 analyzed, distance
protection relays of a large proportion of the fault
has been found to be phase ground fault. This shows
that due to the loading line overcurrent fault or
phase-to-phase fault originating from the
conductives contact to each other are not seen. The
equipment was contaminated under the influence of
environmental conditions and due to the coastal
region moisture has led to formation of discharge in
the transmission line which selected.
Failure count becomes low, interruption time has
decreased. After each failure occurred, transmission
line not becomes active. Because it needs to be
replaced damaged equipment during fault.
Obtained results, the proposed method in this article
method shows that the implementation and
performance plays an important role in preventing
power outages that may occur in the transmission
lines.
Keywords
