Cîhanên Pêşdestkirinê yên Bîkarhatin di Henev (Ser Ser) de

Pîşeyên Bêdewer

Piştgirîn pênc pîşey bêdewer di rêzikên barkirinê de bikar an: Pîn, Sûspensîyon, Strayn, Stay, û Shackle.

• Pîn Insulator

• Sûspensîyon Insulator

• Strayn Insulator

• Stay Insulator

• Shackle Insulator

Pîn, Sûspensîyon, û Strayn insulators di sisteman medium derbasînan derbasîne. Heke Stay û Shackle Insulators di taybetmendiyên derbasînan bi wek nezîk bikar an.

Pîn Insulator

Pîn insulators yekem pîşe yên bêdewer yên ser deman dideyên barkirinê ne hatiye vêrastkirin û heta yê din di şebêkan ênêreya 33 kV de girîng bikar an. Dibe ji bo her derbasîna da çêk behten ji bo bir, du, û sê parçeyan bêtiribîn.

Di sisteman 11 kV de, mîna yek parçeyan type insulator bikar an, ku ji yek parçeyan porcelan û glass ve were xazîn kirin.

Çimke li gorî pîşey bêdewer li ser rûpelê wekî reyekî, zêdekirina hêlka vertikal ya rûpelê yêda destûrê li ser rûpelê werdiha. We yek, du, û ya din rain sheds û petticoats di cismê insulatora de were berdestkirin bi tenê ku destûrê li ser rûpelê werdigire.

Li ser lêserîn wê, rain sheds û petticoats di insulatora de ser pirsgirêkên din dikarin. Wê were xezankirin bi tenê ku li ser baranîn rûpelê ser rûpelê werdegire vala nabe û nekonduktîf bike. Naha yek reyekî destûrê li ser rûpelê pin insulatora bêdewer nabe.

Di sisteman derbasînan yê derbasîne - wisa 33KV û 66KV - vêrastkirina yek parçeyan insulatora porcelan pîn zor dibînin. Di navbera derbasînan, pîn insulator bi tenê ku binêrîn bêtiribîne dikare piştînin bêtiribîn bêdewerê. Yek parçeyan insulatora porcelan binêrîn bêtiribîn vêrastkirina teker nabe.

Li virê caseyê, we bikar anîn parçeyan pîn insulator, ku yek parçeyan porcelan bêtiribîn bi Portland cement fix kirin bi tenê ku yek yekamîn insulator werdigire. Mîna bikar anîn du parçeyan pîn insulators ji bo 33KV, û sê parçeyan pîn insulator ji bo sisteman 66KV.

Berdestkirina Pîşey Bêdewer

Kabê derbasîn di ser serok insulatora pîn de hatiye girtin, ku derbasîn live potential yêda. Bin insulatora di ser struktura pêştimîn de fix kirin bi tenê ku potential yêda. Insulator divê potansîyal stressên di navbera kab û zemin de bixebitîne. Girra kamta di navbera kab û zemin, navendî insulatora cism, di navbera ku qetaya elektrîkî li ser havayê were bigere, belîn flashover distance.

Heke insulatora be wet, rûpelê ser rûpelê yêda konduktîf bike. Belî flashover distance insulatora werdigire. Berdestkirina insulatora bêtiribîn divê wekî reyekî ku flashover distance li ser rûpelê insulatora be wet girîng nabe. Belî pîvêkî ser rûpelê pin insulatora wekî umbrellayê were xezankirin bi tenê ku wê bibîne rest lower part of the insulator from the rain. Rûpelê ser rûpelê pîvêkî ser rûpelê topmost petticoat li ser rûpelê be wet îndikandin.

Rain sheds were made in such a way that they should not disturb the voltage distribution. They are so designed that their subsurface at a right angle to the electromagnetic lines of force.

Post Insulator

Post insulators similar to Pin insulators, but post insulators are more suitable for higher voltage applications.

Post insulators have a higher number of petticoats and a greated height compared to pin insulators. We can mount this type of insulator on supporting structure horizontally as well as vertically. The insulator is made of one piece of porcelain and it has clamp arrangement are in both top and bottom end for fixing.

The main differences between pin insulator and post insulator are:

Suspension Insulator

In higher voltage, beyond 33KV, it becomes uneconomical to use pin insulator because size, weight of the insulator become more. Handling and replacing bigger size single unit insulator are quite difficult task. For overcoming these difficulties, suspension insulator was developed.

In suspension insulator numbers of insulators are connected in series to form a string and the line conductor is carried by the bottom most insulator. Each insulator of a suspension string is called disc insulator because of their disc like shape.

Advantages of Suspension Insulator

• Each suspension disc is designed for normal voltage rating 11KV (Higher voltage rating 15KV), so by using different numbers of discs, a suspension string can be made suitable for any voltage level.

• If any one of the disc insulators in a suspension string is damaged, it can be replaced much easily.

• Mechanical stresses on the suspension insulator is less since the line hanged on a flexible suspension string.

• As the current carrying conductors are suspended from supporting structure by suspension string, the height of the conductor position is always less than the total height of the supporting structure. Therefore, the conductors may be safe from lightening.

Disadvantages of Suspension Insulator

• Suspension insulator string costlier than pin and post type insulator.

• Suspension string requires more height of supporting structure than that for pin or post insulator to maintain same ground clearance of current conductor.

• The amplitude of free swing of conductors is larger in suspension insulator system, hence, more spacing between conductors should be provided.

Strain Insulator

A suspension string used to handle significant tensile loads is called a strain insulator. It is used where there is a dead end or sharp corner in the transmission line, requiring the line to bear a heavy tensile load. A strain insulator must have considerable mechanical strength as well as the necessary electrical insulating properties.

Stay Insulator

For low voltage lines, the stays are to be insulated from ground at a height. The insulator used in the stay wire is called as the stay insulator and is usually of porcelain and is so designed that in case of breakage of the insulator the guy-wire will not fall to the ground.

Shackle Insulator

The shackle insulator (also known as a spool insulator) is usually used in low voltage distribution network. It can be used in both the horizontal or vertical positions. The use of such insulator has decreased recently after increasing the using of underground cable for distribution purpose.

The tapered hole of the spool insulator distributes the load more evenly and minimizes the possibility of breakage when heavily loaded. The conductor in the groove of shackle insulator is fixed with the help of soft binding wire.