School of Civil Engineering, SASTRA University, Thanjavur, Tamilnadu, India
The distances of electric poles and houses were not considered to the fullest extent while giving electrical connections of houses there by paving way for uneconomic situations. The availability of electric poles for a certain area is in such a way that some of the electrical connections given to houses are from nearby poles and that of other houses to faraway poles while compared with respect to the distance. If the connections given were to faraway poles, the required length of wires will be more and the stability due to air etc. will be less. Hence, it is important to give due priority of the connections to be given to houses from different poles. In this paper, a methodology using GPS and Buffer Wizard of Arc Map GIS software has been explained for optimising the service wires.
The spatial data for houses and electric poles was acquired using Global Positioning System (GPS) and fed into Geographical Information System (GIS). Buffer Wizard of ArcMap GIS was used for feasibility study of electrical connections. Two electric poles nearer to a house, by view, were selected. The distance between any one of the selected poles and the house was measured using GIS software from the shape file created and the same was given as buffer distance for drawing the buffer. If it was found that no pole exists inside the buffer, then the connection could be given to the pole with which the buffer is drawn. Else, if any one of the poles was found inside the buffer, then connection could be given to that particular pole so that the length of the wire used for connections can be reduced. Factors like availability of trees, water bodies, transformer capacity and phase connections may be supplemented with buffer analysis for optimising new electrical connections for better accuracy.
This method was implemented for studying the feasibility of available electrical connections with the poles in part of Kabisthalam village, Thanjavur district, Tamilnadu, India extending between 10˚ 56’35” and 10˚ 56’42”N latitudes and 79˚ 15’03”and 79˚ 15’09”E longitudes.
The non-spatial data like the electrical connections of houses with concerned poles were collected from the Tamilnadu Electricity Board, Kabisthalam. The spatial data (latitude and longitude) of the houses and poles was acquired in person using a handheld GPS. The spatial coordinates collected were given as input to ArcMap GIS software through Add xy data of Tools menu and converted to shape file. The creation of new field tables with house numbers was done using the ArcMap GIS. The data collected from TNEB was fed in GIS and a shape file for electrical connections was created. The electrical connections for respective houses are shown in Figure1.
A pilot analysis for feasibility was discussed for two different houses numbered 3/199 and 3/210. For house 3/199, it is clearly identified in Figure 1 that electric poles kp170 and kp163 were at nearer distance from the house. Hence, kp163, kp170 and house 3/199 were considered for buffer wizard analysis. The existing connection was between house and pole kp170 and thus the buffer was drawn using the distance between the house and pole kp170. The output is shown in Figure 2. In Figure 2, the electric pole kp163 was found inside the buffer and it is inferred that the economic mode of connection is that of house with kp163. Similarly for the house 3/210 as shown in Figure 1, kp168 and kp167 were found closer. Hence 3/210, kp168 and kp167 were selected for buffer wizard analysis. Since the existing connection was found between kp167 and house 3/210 in Figure 1, the buffer was drawn between kp167 and 3/210 and the result is shown in Figure 3 from where it can be concluded that the existing one is economical.
Thus, it is concluded that the use of GIS buffer wizard for feasibility analysis of electrical connections is more efficient since accurate predictions were possible for the reason that it involves spatial data and this analysis consumes very less time. It can be used for deciding the electrical connections that are to be given in future so that economy and efficiency can be achieved.
Figure 1: Existing Electrical Connections of Houses with Electric poles. The blue dots indicate availability of houses with their identification numbers. The nine electric poles and their available connections with the different houses are distinctly shown using different colours.
Figure 2: Buffer Map for House No 3/199. The nearby available electric poles for the house 3/199 seen over from figure 1 are shown as kp163 and kp170 using blue and red colours for distinction. The pole kp170 is connected to the house 3/199 at present. Buffer, shown in light blue colour is drawn for the distance between kp170 and house 3/199. The buffer results show pole kp163 is nearer by distance, as it is present inside the buffer. Hence the available connection is not feasible.
Figure 3: Buffer Map for House No 3/210. The nearby available electric poles for the house 3/210 seen over from figure 1 are shown as kp167 and kp168 using blue and red colours for distinction. The pole kp168 is connected to the house 3/210 at present. Buffer, shown in pink colour is drawn for the distance between kp168 and house 3/210. The buffer results show pole kp168 is nearer by distance, as kp167 is found outside the buffer. Hence the available connection is feasible.
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