Misalai a Cikin Tsuron Karamin Kirki?
Me kadan Sag a Overhead Conductor?
Takaitaccen Sag
Sag a linya da ke koyarwa yana nufin fassan masu tarihi daga cikin hukuma da suka fi shi da zama mai yawa na conductor.
Dalilai Sag
Amfani da sag mai yawa yana ba linyar koyarwa gaskiya da tsayi da karfi ga tashin tarihi da adadin mafi yawa, hasisen da ake amfani da ita a wurare da abubuwan da ba a yi laifi.Sag yana bukatar a cikin suspension da conductor. Conductors suna haɗa a nan biyu da sag mai yawa.Sag yana da muhimmanci saboda yana ba waɗanda conductors bata zuwa karfin tarihi da adadin mafi yawa, wanda ya ci gaskiyar damar ita.
Idan ake saka conductor daidai a lokacin tattalin, ido yana ba shi karfi, saboda haka conductor yana samun sakamako ko ake kawo daga dukkanta. Saboda haka ana amfani da sag a lokacin suspension da conductor.
Abubuwan da ya danganta a duba
Idan dukkantuka biyu na sama ta shahara suna haɗa da conductor, za a faru shape mai kasa a cikin conductor. Sag yana da alama da yawa a matsayin span da conductor.
Curve da take faruwa a kan sag na parabolic.
A cikin kowane yanayi a kan conductor, karfi yana daidai tangential, wanda ya ci gaskiyar balanci a kan span.
Karrabu mai horizontal da ke karfi a kan conductor yana daidai a duk inganci da conductor.
Karfi a dukkantukan yana daidai da karfi a kowane yanayi a kan conductor.
Takaitaccen Tushen Saki
Idan an tabbatar da sag a linya da ke koyarwa, an buƙata abubuwa biyu da za a duba:
Idan dukkantukan suka da matafiyoyi daidai
Idan dukkantukan ba suka da matafiyoyi daidai ba
Formula da ake amfani da ita don tabbatar da sag yana yawan sa a kan abin da dukkantukan (wato transmission towers da ke haɗa da overhead conductor) suka da matafiyoyi daidai.
Tushen Saki Idan Dukkantukan Su Da Matafiyoyi Daidai
Suppose, AOB shi ne conductor. A da B su ne points of supports. Point O shi ne lowest point da kuma midpoint.Let, L = length of the span, i.e. ABw is the weight per unit length of the conductorT is the tension in the conductor.We have chosen any point on the conductor, say point P.The distance of point P from the Lowest point O is x.y is the height from point O to point P.
Equating two moments of two forces about point O as per the figure above we get,
Tushen Saki Idan Dukkantukan Ba Su Da Matafiyoyi Daidai Ba
Suppose AOB shi ne conductor da ke da point O as the lowest point.L is the Span of the conductor.h is the difference in height level between two supports.X 1 is the distance of support at the lower level point A from O.x2 is the distance of support at the upper-level point B from O.T is the tension of the conductor.w is the weight per unit length of the conductor.
So, having calculated the value of x 1 and x2, we can easily find out the value of sag S1 and sag S2. This formula calculates sag under conditions of still air and normal temperature, where only the conductor’s own weight affects it.
Environmental Impact
Some of the effects of ice and wind on sag include:
The weight per unit length of the conductor is changed when the wind blows at a certain force on the conductor and ice accumulate around the conductor.
Wind force acts on the conductor to change the conductor self-weight per unit length horizontally in the direction of the airflow.Ice loading acts on the conductor to change the conductor self-weight per unit length vertically downward.Considering wind force and ice loading both at a time, the conductor will have a resultant weight per unit length.
The resultant weight will create an angle with the ice loading down ward direction.Let us assume, w is the weight of the conductor per unit length.wi is the weight of ice per unit lengthwi= density of ice × volume of ice per unit length w is the force of wind per unit length.ww = wind pressure per unit area × projected area per unit length
So, the total weight of the conductor per unit length is
The sag in the conductor is given by
So the vertical sag
Safety Considerations
Proper sag calculation is vital for maintaining the structural integrity and operational reliability of transmission lines.
