Example Problem #1 230kV XLPE Cable Splice

Example Problem #1 230kV XLPE Cable Splice Description: Dielectric model of a cable splice consisting of two conductors, crimp connector, insulation, and an outer shield. Solver: 2D RZ Electrostatic

Example Problem #1 230kV XLPE Cable Splice Basic Procedure: Create new 2D Electrostatic project Import cable.sm2 file, and make four modifications as necessary Setup materials Setup boundaries/sources Solve Post Process

Example Problem #1 230kV XLPE Cable Splice Step 1: Create 2D RZ Electrostatic project: splice The splice.pjt will open automatically

Example Problem #1 230kV XLPE Cable Splice Step 2.1: Change drawing plane to: RZ Plane Verify that the solver is set to: Electrostatic Enter the modeler using: Define Model/Draw Model File Import/ ../emprojects/floppy/cable.sm2

Example Problem #1 230kV XLPE Cable Splice Step 2.2: Set grid: Window/Grid/Suggested Spacing/Ok or hit “g” on keyboard/Suggested Spacing/Ok Change units to mm: Model/Drawing Units/mm/Rescale to new units/Ok Change view: Window/Change View/Fit All of hit “f” on keyboard

Example Problem #1 230kV XLPE Cable Splice Step 2.3: Zoom in Reset grid: Window/ Grid/ Suggested Spacing/ Ok Draw crimp connector using polyline command: Object/ Polyline Name: connector Color: green

Example Problem #1 230kV XLPE Cable Splice Step 2.4: Modify e_shield by removing edge and adding lower arc Zoom in Reset grid: Window/ Grid/ Suggested Spacing/ Ok Delete lower straight edge: Reshape/edge/delete Add additional vertical edge: Object/Polyline/click/double click to end Create clockwise arc: Object/Arc/clockwise/Ok click on center/click on start point/click on end point/Ok/Ok Select e_shield and then Boolean/ Simplify to remove extra vertices that are not necessary (refer to drawing on next page)

Example Problem #1 230kV XLPE Cable Splice 10mm

Example Problem #1 230kV XLPE Cable Splice Step 2.5: Modify block insulator: Zoom in Turn on hatches for block insulator Move vertex on epoxy block insulator: reshape/vertex/move Turn off hatches for block insulator

Example Problem #1 230kV XLPE Cable Splice Step 2.6: Duplicate top cable insulation to create the bottom insulation: Edit/ Deselect All Click inside of top cable insulation to select it Edit/Duplicate/ Mirror duplicate/ click on (0,0) click on (100,0) to “define mirror” Edit/Attributes/Rename/ (type in insul_bottom)/ Rename/ Ok to change the copied object to insul_bottom

Example Problem #1 230kV XLPE Cable Splice Step 2.7: Finish modifying and exit: Fit model to window: f Fill solids: [control-hold] f Edit/ Visibility/ Show All Deselect All File Save/File Exit

Example Problem #1 230kV XLPE Cable Splice Step 2.8: Group objects with same material and excitation (voltage) together: Define model/Group Objects insul_top/insul_bottom  insulation/Ok cond_top/cond_bottom  conductor/Ok/Exit/Yes

Example Problem #1 230kV XLPE Cable Splice Step 3: Setup Material Properties: [conductor] and connector/copper/assign e_shield and outershield/aluminum/assign Material/add/XLPE1/eps=3.25/cond=0/Enter [insulation]/XLPE1/assign Material/add/XLPE2/eps=7.0/cond=0/Enter [block_insulator]/XLPE2/assign Background/ Exclude/ Exit

Example Problem #1 230kV XLPE Cable Splice

Example Problem #1 230kV XLPE Cable Splice Step 4: Setup Boundary/Sources: Edit/Select/Object/by clicking/ conductor, connector, and e_shield/ right click Assign/Source/Solid/Name: line/132800 volts/Assign Edit/Select/ Object/by clicking/ outershield/right click Assign/Source/Solid/Name: ground/0 volts/color green/Assign File/Save/File/Exit

Example Problem #1 230kV XLPE Cable Splice Step 5: Solve the problem: Solve/Nominal problem (please note it is not always necessary to go into Setup Solution/Options) View the Convergence table View the Profile information

Example Problem #1 230kV XLPE Cable Splice

Example Problem #1 230kV XLPE Cable Splice Step 6.1 Post process the problem and create an equipotential plot: Select the Post Processor/Nominal Problem Plot/Field/Plot Quantity: phi/ On Geometry: Surface -all- / In Area: -all- / Ok Uncheck filled (to get a contour plot) and accept all other default conditions by clicking on Ok

Example Problem #1 230kV XLPE Cable Splice

Example Problem #1 230kV XLPE Cable Splice Step 6.2 Create an E-field plot: Choose Plot/ Visibility and turn off the voltage plot Plot/Field/Plot Quantity: mag E / On Geometry: Surface -all- / In Area: -all- / Ok Check filled to get a shaded plot Select “use limits” and change maximum to 2e7 Accept all other default conditions by clicking on Ok

Example Problem #1 230kV XLPE Cable Splice E-field in V/m

Example Problem #1 230kV XLPE Cable Splice Step 6.3 Change the units on the E-field plot to kV/mm: Choose Plot/ Visibility and turn off the E-field plot Select Data/ Calculator Choose Constant/ Conversion Constants and select: Quantity: ElectricField, From V/m, To kV/mm and click on Ok Exch/ Rlup/ * / RlDn Plot/ Name: E (kV/mm) Change maximum to 20 instead of 2e7 Accept all other default conditions by clicking on Ok

Example Problem #1 230kV XLPE Cable Splice E-field in kV/mm

Example Problem #1 230kV XLPE Cable Splice Step 6.4 Graph E-field along front of e_shield using the line already created in the 2D modeler: Choose Plot/ Visibility and turn off the E (kV/mm) shade plot Select Data/ Calculator Pop/ Geom/ Line/ e_shield_front/ ok/ 2D plot/ Name: Magnitude/ ok Note: the line e_shield_front was drawn in the modeler and was automatically imported into the post processor

Example Problem #1 230kV XLPE Cable Splice Step 6.5 Decompose E-field along front of e_shield into R, Z, normal, and tangential components: Select: Data /Calculator /Quantity/ E/ Smooth/ Number/ Scalar/ 1e-6/ ok/ * Scalar R/ exchange/ 2D Plot/ Name: R component/ ok Exchange/ Undo/ Scalar Z/ Exchange/ 2D Plot/ Name: Z component/ ok Exchange/ Undo/ Exchange/ Normal/ Undo/ 2D plot/ Name: Normal/ ok Exchange/ Undo/ pop/ Exchange/ Tangent/ Undo/ 2D plot/ Name: Tangent/ ok Choose Plot/ Format/ Axis and add following descriptions: Heading: Components of E Field along front of shield X Label: Distance (mm) Y Label: E Field (kV/mm)

Example Problem #1 230kV XLPE Cable Splice