Ministry of Power, Govt. of India, as a part of Reforms in the Power Sector, has launched the Restructured Accelerated Power Development and Reforms Programme (R-APDRP) as a Central sector scheme on July, 2008. The focus of the program is on the actual demonstrable performance in terms of AT&C loss reduction, establishment of the reliable and automated sustainable systems for collection of base line data, adoption of information technology in the areas of energy accounting, consumer care and strengthening of Distribution network of State Power Utilities.
RAPDRP Work Undertaken by Coordtech
- Town boundary identification and mapping within the area of interest(AOI)as per the physical ring fencing by the utility.
- Lead time for procurement of satellite images & finalization of AOI.
- Base map preparation through conversion of satellite imagery of 1M resolution for listed town areas (AOI).
- Surveying of existing geographic features such as Buildings, Roads, Railways, Water bodies, Trans structures and Collection of Important landmarks (Govt. offices, Religious places, Building Names, Shops, Street Names, educational institutes ,major transportation centers etc.).
- DGPS survey (sub meter accuracy) of substations (33KV/11KV),Poles and Distribution Transformers located within town area (AOI) with attributes as per the prescribed format for different types of assets.
- Identification and tracking of service line through hand sketch(SLD) during “Door to Door” survey for consumer indexing.
- Asset code of all assets (Transformers, Poles and Breakers etc including LT poles) is to be legibly painted on the asset as per the specified color scheme by the Utility, surface preparation, etc to be done before painting.
- Periodical submission of softcopy and hardcopy as per the instructions/ requirements from the Utility.
RAPDRP Methodology by Coordtech
As the field survey for both Electrical assets and consumer data are challenging tasks in this project, our approach begins with building the fruitful relations with the technicians of Power Distribution companies.
With the help of low level technicians (Line men), feeder route and its designations, limits and other possible existing data will be gathered.
As we have already in process of recruiting the Senior persons (Rtd.) from the Discoms as consultants for this project, the above task will be made easy.
To minimize the risks in consumer data collection, the surveyors are recruited locally town wise and sub-division wise. And required training will be provided.
DGPS Devices will capture the Latitude and Longitude of Electrical Assets. For this the DGPS Base Station should be established at central station and the surveying people will take the DGPS Rovers for surveying Electrical Network. All the collected data should be overlaid on to the Geo-referenced Base Map.
Network surveyors will follow the maps along with technicians of Discoms to collect the pole and other asset locations with DGPS.
The proposed work specified the attributes to be collected for GIS Survey and Consumer Indexing. The exhaustive list of attributes data to be collected for all the Electrical Assets as per the scope of work. Further, the Network Analysis Tool is also being implemented the data requirement for the above tools is also to be surveyed.
We will process base map from satellite imagery of 0.6m(can be changed as per proposal) resolution. The image should be provided by Client.
Image will be studied to capture some of the prominent locations (at least 5 points in each square kilometer area). Positional details (latitude, longitude and altitude) will be collected through a DGPS survey for the locations identified. These details are then used in the process of registering the map. Industry standard GIS/Image processing tools will be used to carry-out the process of rectification & registration.
It is often necessary to locate a satellite image, or an aerial photograph in its correct spatial location and orientation for use as a backdrop in a GIS display or map. The name given to various methods used to accomplish this is Geo-rectification.
Geo-rectification involves identifying Ground Control Points (GCP) on both the image and in relation to a known datum. Software is then used to resample the image such that its spatial location and orientation best matches that defined by the selected GCPs. GCPs will ideally be spread throughout the image with a good coverage near the edges.
Base map preparation through conversion of satellite imagery (Buildings, Roads, Railways, Water bodies, Trans structures and Collection of Important landmarks).
Base map will be created to the scale of 1:1000 for each project area under both R-APDRP.
Town maps (scale 1:10,000 to 1:20,000) will be (obtained from local government agencies) used for the further reference.
New features will be captured / updated using satellite imagery / DGPS survey.
Separate layers of town maps / SOI toposheets / satellite imagery will be created and stored after rectification in digital form. The network map will be integrated with the background map.
A group of separate and dedicated team will be deployed to assess the quality of the map production. Quality check will be conducted at two levels: - On Screen Quality Check - Paper Quality Check
This process will ensure that there are no missing features, misplaced features, wrong attribution / annotation and also ensures that the defined map standards are maintained (like size of annotation, thickness and color of line features, dimension of point features etc).
Electrical Network Asset Survey and Consumer Indexing
Substation Survey: The dedicated GIS team of Coordtech collected overall 11kV Network distribution layout from utility (Site). Visited the substation and collecting Latitude-Longitude of the periphery of substation area through DGPS survey. DGPS data collection of all electrical assets within the substation (control room, power transformer, switch gear, current transformer, potential transformer, station transformer, Earth Switch, Lightning Arrestor, Isolator, Circuit Breaker etc.) as per the asset list and gathered attributes against all asset categories in consultation with on site people. Post processing, digitization of all asset categories over prepared base map and attachment of collected attributes, codification of all electrical attributes as per the specified codification logic.
HT Network Survey: Coordtech conducted HT Network survey including survey of all electrical attributes from 33/11 KV substation downwards up to distribution transformers and HT Poles. Preparation of Data Dictionary File (In DGPS Mobile application) for all individual asset categories as per the finalized attribute list along with Feeder wise HT Line survey initiated from Substation. Surveyors appointed had to move along with the 11 KV feeder line. DGPS data collection and attribute collection of all HT Poles, Feeder Line, Distribution Transformers, Fuse, Capacitor, Series Capacitor and DP Isolator etc. as per the predefined file format (DDF). All HT Poles, DTRs etc were collected as Point features in DGPS and attributes were collected against individual assets. Similarly HT Feeder lines etc. were identified as DGPS line features along with all related attributes. Different asset categories were collected in separate layer through DGPS. After identification of all Distribution Transformers within the AOI, separate data collection process initiated to collect attribute data from name plate of the distribution transformer. This data collection process included temporary shutdown of DTR connection, climbing on the DTR mounting structure and note down the required attributes. Necessary precautions had to be taken during the DTR data collection process. Attribute data were collected from different levels of utility (Supply Unit, Sub Division, Division, Circle etc.). Data download, spatial differential correction and digitization of all survey output to prepare the HT Network map after required attribute data attachment. Superimposition of prepared HT network map over the base map, and satellite imagery to visualize the actual network distribution was also done. Layout, printing and submission of HT Network map to corresponding division for checking, and rectification. This process includes sample QC (In house / on field) to identify the errors and followed by the essential rectification process. Final submission of HT Network map is done after required changes for 100% coverage approval.
LT Network Survey: Coordtech has conducted a DTR wise LT Network survey includes survey of all electrical assets from DTR downwards up to LT Poles. The LT network survey was similar to the HT Line survey with DGPS point collection and attributes collection for all LT Poles and associated electrical assets. Data downloading, post processing, data attachment and digitization of different layers were the processes to follow the DGPS survey to prepare the output map. In house as well as field QC to minimize the error percentage was carried out. Codification of all assets to built hierarchical relationship, mapping and layout preparation DTR wise for submission along with DTR wise LT network attribute details.
Codification and Painting on Assets: After completion of in house codification HT Feeder wise layout was prepared for field verification of HT Network. Similarly for LT Network verification, DTR wise layouts have to be prepared and printed. Field supervisor of Asset Painting Team went for the on field asset identification and stick the preprinted code on the asset for code painting. Colored base preparation for code writing has to be executed simultaneously with the asset identification process. After asset identification by the supervisors, Location code of assets (Distribution Transformers, HT Poles, LT poles) is to be legibly painted on the asset as per the specified scheme by the Utility.
Consumer Survey: Consumer Survey was taken up immediately after the Asset Survey or simultaneously with the asset painting. For Consumer Survey Catchment area for each transformer was taken up at a time. The consumer Survey process required door to door visit of each premise and collection of Database. Consumer surveyors were provided with the partially filled up forms (maximum fields available from existing consumer database). Consumer surveys also followed the pole code for identification of network hierarchy of the consumers. Local People involved during consumer survey for smoother survey process. Administrative help was taken from local supply office in case of refusal and in accessibilities. Consumer coding was done on the basis of approved Consumer Codification from the utility. Billing Database already available with the utility used as a reference to understand the number of consumer and to cross check the collected consumer database.