GIS BASED DISTRIBUTION SYSTEM PLANNING

Abstract

The electrical energy produced at the generating station is conveyed to the consumers through a network of transmission and distribution system. In general, distribution system is that part of power system which distributes power to the consumers for utilization. The major objective of a utility is to supply the power demand with good quality of service, through proper planning of the system. This has led to development of methods which can be used to aid the decision making process for selecting best alternative. GIS (Geographical Information System) based electricity distribution system modeling is an approach to determine an optimum planning strategy. It can facilitate information about customers, inventory, routing of distribution line, economic analysis of routing at the stage of planning, poles and overload conditions in the future period, running a load flow analysis etc. A GPS (Global Positioning System) device can also serve in a very effective and useful way for planning of electricity distribution system network. In GIS based distribution system planning GIS software is to be chosen. In this dissertation, a GIS based software ARC VIEW GIS 3.2a has been chosen for the analysis of the existing route of the radial distribution system network and location of poles of IIT Roorkee, in the form of their latitude and longitude are obtained after surveying with a GPS instrument. A three dimensional model of distribution system network has also been prepared using GIS and GPS technology. Three new layouts of the routing have been proposed which are shorter as well as feasible. A comparison between load flow analysis of existing and proposed layouts of distribution system has been performed to find out the effects on the system losses and voltage profile after finding new layouts of distribution system. Optimum conductor has been selected for each feeder. Then for finding out the optimum layout among three, cost comparison is done, which will provide the most economically- viable layout. The power flow or load-flow studies are essential for the planning of future expansion of power system as well as for determining the best operating condition of existing systems. The information obtained from the power flow study is the magnitude and phase angle of the voltage at each bus and the real and reactive power flowing in each line. Thus load flow, forms an important part of power system analysis. In addition, distribution networks extends to wide areas and contain a very large number of elements, like substations, line sections, loads of different types etc. These networks are composed of many feeders operating radially in normal conditions. The proper choice of multi-conductor cross section for radial feeders in the distribution system improves the system economy without affecting technical requirements of the system. The developed system is tested on 57 buses, 56 branches, and 6 feeders of a sample substation of IIT Roorkee distribution system. The complete set of data required for the load flow analysis including the bus voltage, line currents, kW loads, power factor, meter reading, hourly data as well as spatial data required for GIS such as location of all the substations, buses and alignments of all 11 kV and 440 volts feeders, rates of accessories used for the electricity distribution were collected in an extensive ground survey. iv