Successful Implementation of GIS Techniques for
Route Alignment & Surveys of Power Transmission Projects
of POWERGRID
Power Grid Corporation Of India Ltd
To optimize cost of transmission line
Line length, number of locations, deviations Minimum river crossings Minimum forest areas Accessibility, right of way considerations To assess route constraints and do construction planning
To ensure statutory clearances
Ground clearance Horizontal/Right of way clearance Clearances from power lines, railway lines, road crossings etc.
Why Surveying Is Important ?
UHV Transmission Lines UHV Transmission Lines - 765 kV , Requiring Large ROW - 765 kV , Requiring Large ROW
Long Distance Transmission Long Distance Transmission Lines – 500 kV HVDCLines – 500 kV HVDC
Transmission Lines Transmission Lines thru’ Agricultural fieldsthru’ Agricultural fields
Transmission Lines in Hilly areasTransmission Lines in Hilly areas
Multiple Transmission Lines Through Same Corridor
Transmission Line River CrossingsTransmission Line River Crossings
Project Conceptualization / Project Feasibility StageFaster and accurate techniques required to evaluate various line routes
Pre-Construction StageRoute alignment, Detailed Mapping of right of way, ground profiling, finalisation of tower locations with geo technical detailsDetailed contouring of undulated terrain for estimation of benching and revetment quantities
Project Construction StageCheck Survey only
Transmission Line Surveying
Large Quantity variations during execution stage avoided Constraints assessed in advance Engineering activities can be taken in advance Construction work can be taken up immediately after
contract award Reduction in IDC due to reduction in project execution time – offsetting cost of survey using modern techniques Reduction of even 1-2 kms line length would offset
cost of surveying using modern techniques
Advantages of Conducting Detailed Survey in Advance
Detailed Survey – Modern TechniquesDetailed Survey – Modern Techniques
Route Alignment using latest satellite Route Alignment using latest satellite imageries (PAN + LISS III Merged imageries (PAN + LISS III Merged products) superimposed on Survey of products) superimposed on Survey of India Topographical MapsIndia Topographical Maps
Digital terrain modeling in hilly terrain Digital terrain modeling in hilly terrain using contouring datausing contouring data
Detailed Survey using GPS, Total stations Detailed Survey using GPS, Total stations or alternatively ALTMor alternatively ALTM
Digitized contouring at undulated / hilly Digitized contouring at undulated / hilly tower locationstower locations
Identification of Route constraints,Identification of Route constraints, Identification of infrastructure details Identification of infrastructure details
Detailed Survey – Modern Detailed Survey – Modern TechniquesTechniques
Tower spotting & optimization of Tower spotting & optimization of locations using commercial software locations using commercial software like PLS CADDlike PLS CADD
Estimation Of BOQEstimation Of BOQ Preparation Of Survey reportsPreparation Of Survey reports Soil InvestigationSoil Investigation
METHODOLOGY
Acquisition of Remote Sensing Data
Digitization of Base details from SOI
sheets
Preparation of Updated Digitized Maps
Selection of corridors/alternatives
Route Selection Reconnaissance Survey
GPS/Total Station Survey
Digitized Profiling
Computer-aided tower spotting
BOQ Estimation, Reports etc.
Geotechnical Investigations
Digitized ToposheetDigitized Toposheet
Survey of India Topo Sheet Corresponding Digitized Map indicating relevant information
Digitized Satellite ImageDigitized Satellite Image
Satellite Imagery (5.8/20 m resolution)
Corresponding Digitized Image indicating relevant information
Selection of Alternative RoutesSelection of Alternative Routes
Bee Line
Existing Line
Alternative 3
Alternative 2
Alternative 1
Computerized Route Optimization by Study Computerized Route Optimization by Study of Alternative Routesof Alternative Routes
Bee Line
Existing Line
Alternative 3
Alternative 2
Alternative 1
Digital Terrain ModelDigital Terrain Model
Computerized Three Dimensional Image
Bee Line Alternative-3Alternative-1
Alternative-2
Advantages of Modern Advantages of Modern Survey Techniques over Survey Techniques over
Traditional survey MethodTraditional survey Method
Topographic Sheet – Indicates only Nala
Satellite Image – Indicates Large waterbody
Topographic Sheet – Indicates only a part of Canal
Satellite Image – Indicates Another Branch of Canal
Topographic Sheet – Not many details
Satellite Image – Indicates Recent Infrastructure Developments, Landslide Areas
Transmission Line Survey through GIS
Change of River Course
Detailed Survey on Selected RouteDetailed Survey on Selected Route
Detailed Survey is done on the selected route using Total Stations.
Plotting of Surveyed Route on the Topographical Maps
Tower Spotting and profiling is done using PLS-CADD Software.
PLS CADD Software PLS CADD Software
Power Line Systems Computer Aided Design and Drafting (PLS CADD) is a software developed by Power line systems Inc. USA.
The software is used for Tower Spotting.
The software automatically provide SAG Clearances.
The software automatically calculates wind & Weight Span.
The software prepares the “Plan & Profile View” of the T/L line.
Report Generation.
The overall organization of the PLS CADD software is shown in the following slide.
PLS CADD SoftwarePLS CADD Software
3-D Model of3-D Model ofLine in CorridorLine in Corridor
3-D Terrain3-D Terrain
Survey DataSurvey DataFeature CodesFeature Codes
Design CriteriaDesign Criteria
LoadsLoadsClearancesClearances
StructuresStructures
GeometryGeometryStrengthStrength
CablesCables
All PropertiesAll Properties
ReportsReportsMaterial ListMaterial ListSpecificationSpecification
Etc.Etc.
DrawingsDrawingsPlan & ProfilePlan & ProfileExported toExported toCAD systemCAD system
ArchivingArchivingLineLine
ManagementManagement
FutureFutureModificationsModifications
Corridor TerrainCorridor Terrain
Ground + ObstaclesGround + Obstacles
InstallationInstallationSpottingSpotting
AutomaticAutomaticManualManual
StringingStringingSaggingSagging
Etc.Etc.
CalculationsCalculations
Sag TensionSag TensionClearancesClearances
Struct-StrengthStruct-StrengthSwingsSwings
Etc.Etc.
LibrariesLibraries
InputInput ProcessingProcessing OutputOutput
Plan & Profile DrawingPlan & Profile Drawing
Key AdvantagesKey Advantages
PLS Cadd – software used for PLS Cadd – software used for preparing “Plan & Profile Drawing” preparing “Plan & Profile Drawing” and “Report Generation”and “Report Generation”
Eliminates manual error in Report Eliminates manual error in Report generation.generation.
Empowers Managers to move / modify Empowers Managers to move / modify structures and see the effect on the structures and see the effect on the Line.Line.
Reports / Calculations of modified Reports / Calculations of modified structures can be viewed instantly. structures can be viewed instantly.
Airborne Laser Terrain Mapping(ALTM)
First reflection(first pulse)
Last reflection(last pulse)
The laser locator installed onboard records both returns from the vegetation cover and objects on the ground (that is the first pulse) and from the terrain under the vegetation (that is the last pulse). This system together with data processing software are used to create digital terrain model not affected by the vegetation.
New Line ConstructionNew Line Construction
Knowing exact geometry along the route with as many details desirable as it makes design process much more productive. With laser survey much more efficient and fast to collect the information along the route for new power line design and construction.
Evaluation Of ClearancesEvaluation Of Clearances
Thermal Uprate StudiesThermal Uprate Studies
Thermal uprate study will become much less complicated process with laser survey data. Three-dimensional information about actual power line geometry and condition brings all relevant details along the route of the power line.
TEESTA-V (Route Alignment using satellite imagery) SRINAGAR-LEH (Route Alignment using satellite imagery) PARBATI-II, KOLDAM KAHALGAON BARH KUDAMKULAM NEYVELI RANCHI-SIPAT RAPP-5&6 MAITHON WR STRENGTHENING PARBATI-III URI-II etc. etc.
DETAILED SURVEY USING MODERN TECHNIQUESFOR PROJECTS
– COMPLETED / UNDER IMPLEMENTATION
Thank You