Advanced Substation Grounding Grid Design Touch Potential 3D Graph for Substation ABC PDF

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Advanced Substation Grounding Grid Design Potential (Volt) 960 920 880 840 800 760 720 680 641 601 561 521 481 441 401 361 321 281 242 202 162 122 82 42 2 Touch Potential 3D Graph for Substation ABC EDSA MICRO CORPORATION 16870 West Bernardo Drive, Suite 330 San Diego, CA 92127 U.S.A. © Copyright 20...

Description

Advanced Substation Grounding Grid Design

Potential (Volt) 960 920 880 840 800 760 720 680 641 601 561 521 481 441 401 361 321 281 242 202 162 122 82 42 2

Touch Potential 3D Graph for Substation ABC

EDSA MICRO CORPORATION

16870 West Bernardo Drive, Suite 330 San Diego, CA 92127 U.S.A. © Copyright 2008 All Rights Reserved

Version 4.80.00

October 2008

EDSA MICRO CORPORATION

WARRANTY INFORMATION There is no warranty, implied or otherwise, on EDSA software. EDSA software is licensed to you as is. This program license provides a ninety (90) day limited warranty on the media that contains the program. This, the EDSA User’s Guide, is not meant to alter the warranty situation described above. That is, the content of this document is not intended to, and does not, constitute a warranty of any sort, including warranty of merchantability or fitness for any particular purpose on your EDSA software package. EDSA Micro Corporation reserves the right to revise and make changes to this User's Guide and to the EDSA software without obligation to notify any person of, or provide any person with, such revision or change. EDSA programs come with verification and validation of methodology of calculation based on EDSA Micro Corporation's in-house software development standards. EDSA performs longhand calculation and checks the programs’ results against published samples. However, we do not guarantee, or warranty, any program outputs, results, or conclusions reached from data generated by any programs, which are all sold "as is". Since the meaning of QA/QC and the verification and validation of a program methodology are domains of vast interpretation, users are encouraged to perform their own in-house verification and validation based on their own inhouse quality assurance, quality control policies and standards. Such operations - performed at the user's expense - will meet the user's specific needs. EDSA Micro Corporation does not accept, or acknowledge, purchase instructions based on a buyer's QA/QC and/or a buyer's verification and validation standards. Therefore, purchase orders instructions are considered to be uniquely based on EDSA's own QA/QC verification and validation standards and test systems.

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Advanced Substation Grounding Grid

Table of Contents 1.

ADVANCED SUBSTATION GROUNDING GRID DESIGN CAPABILITIES, FEATURES AND FUNCTIONS ......................................................................................................................................................1

2.

FOREWORD ......................................................................................................................................................2

3.

INTRODUCTION, SUBSTATION GROUNDING...........................................................................................2

4.

SAFETY IN GROUNDING ...............................................................................................................................2

5.

GROUNDING OF AC SUBSTATIONS............................................................................................................3

6.

DESIGN PARAMETERS ..................................................................................................................................3

7.

GROUNDING SYSTEM ANALYSIS ...............................................................................................................3

8.

THEORY AND COMPUTATIONAL PROCEDURES; GENERAL CONCEPT.............................................4

9.

GROUND POTENTIAL RISE (GPR), STEP, TOUCH, MESH........................................................................4

10.

COMPUTATION OF BODY CURRENT..........................................................................................................5

11.

USE OF CRUSHED ROCK LAYER ( rs ).......................................................................................................5

12.

RESISTANCE OF THE HUMAN BODY ........................................................................................................6

13.

BASIC SHOCK SITUATIONS; RECTANGULAR GRID ..............................................................................6

14.

RESISTANCE OF THE GROUND BENEATH THE TWO FEET..................................................................7

15.

COMPUTATION OF ALLOWABLE STEP AND TOUCH POTENTIALS ...................................................7

16.

DETERMINATION OF MAXIMUM GRID CURRENT ................................................................................8

17.

SOIL MODEL ...................................................................................................................................................8

18.

SUMMARY OF THE PROGRAM CAPABILITIES .....................................................................................11

19.

INPUT DATA .................................................................................................................................................11

20.

MENUS OF SUBSTATION GROUNDING GRID DESIGN PROGRAM....................................................12

21.

HOW TO SETUP A STUDY CASE ...............................................................................................................15

22.

EXAMPLE OF SUBSTATION GROUNDING GRID ASSEMBLY HAVING SLANTED RODS .............29

23.

TUTORIAL EXAMPLE .................................................................................................................................33

24.

A FEW IMPORTANT NOTES.......................................................................................................................53

25.

SUPPLIED EXAMPLES WITH THE SUBSTATION GROUNDING GRID DESIGN PROGRAM ...........56

26.

SOIL MODEL IN EDSA’s ADVANCED GROUNDING GRID DESIGN PROGRAM...............................57

27.

REFERENCES ................................................................................................................................................58

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Advanced Substation Grounding Grid

List Of Tables

Table 1: Sample Soil Resistivity Measurements Using Wenner Method ...................................... 10 Table 2: List of Supplied Examples (Jobfiles) .............................................................................. 56 List Of Figures

Figure 1: Basic Shock Situations..................................................................................................... 6 Figure 2: Example of a Rectangular Grid ...................................................................................... 6 Figure 3: “Wenner” Soil Resistivity Test Method.......................................................................... 9 Figure 4: Starting Substation Grounding Program from EDSA Technical 2005 Main Menu..... 15 Figure 5: Main Menu of The Substation Grounding Program..................................................... 15 Figure 6: Opening A New Job file ................................................................................................ 16 Figure 7: General Data Dialog of Substation Grounding............................................................ 16 Figure 8: General Substation Data Dialog .................................................................................. 17 Figure 9: Soil Resistivity Model Data Dialog .............................................................................. 18 Figure 10: Defining the Substation Grid Land Size ..................................................................... 19 Figure 11: Regular Ground Grid Data Dialog ............................................................................ 19 Figure 12: Entering Regular Grid Data....................................................................................... 20 Figure 13: Ground Grid Rod Data Dialog................................................................................... 20 Figure 14: Viewing Substation Ground Grid Layout ................................................................... 21 Figure 15: Selection EquiPotential Calculation Option Icon ...................................................... 24 Figure 16: Defining Area for EquiPotential Calculation (setting the start point) ....................... 25 Figure 17: Defining Area for EquiPotential Calculation (setting the end point)......................... 25 Figure 18: Data Dialog for Defining Area for EquiPotential Calculation .................................. 26 Figure 19: Calculated EquiPotential Lines Plot .......................................................................... 26 Figure 20: Copying EquiPotential Plots to the Clipboard........................................................... 27 Figure 21: Printing Text Result Report for EquiPotential Calculation ....................................... 27 Figure 22: Sample Text Report..................................................................................................... 29 Figure 23: Sample Jobfile using Grounding Grid Assembly Having Slanted Rod....................... 29 Figure 24: Icons for Defining Multiple Slanted Rods and/or Single Slanted Rod ....................... 29 Figure 25: Data Dialog for Defining Single Slanted Rod ............................................................ 30 Figure 26: Data Dialog for Defining Multiple Slanted Rods ....................................................... 31 Figure 27: Multiple Slanted Rods Added...................................................................................... 31 Figure 28: EquiPotential Lines Plot for Sample Jobfile With Slanted Rods................................ 32 Figure 29: Substation Layout of a L-Shaped Grid with Ground Rods, IEEE80-2000 ................. 33 Figure 30: Opening a New Job File, IEEE80-2000 -- example b-4............................................. 34 Figure 31: General Data Dialog, IEEE80-2000 –example-b4 .................................................... 34 Figure 32: General Substation Data Dialog, IEEE80-2000-example-b4 .................................... 35 Figure 33: Soil Resistivity Data Dialog, IEEE80-2000-example-b4............................................ 35 Figure 34: Defining the substation Grid Land Size, IEEE80-2000-example-b4.......................... 36 Figure 35: Entering Ground Grid Data – Step 1, IEEE80-2000-example-b4 ............................. 36 Figure 36: Entering Regular Grid Data – Screen 1, IEEE80-2000-example-b4 ......................... 37 Figure 37: Entering Rectangular Grid– Screen 2, IEEE80-2000-example-b4 ............................ 38 Figure 38: Entering Rectangular Ground Grid Data – Screen 3, IEEE80-2000-example-b4..... 38 iii

Advanced Substation Grounding Grid

Figure 39: Entering Rectangular Ground Grid Data – Screen 4, IEEE80-2000-example-b4..... 39 Figure 40: Entering Rectangular Ground Grid Data –Screen 5, IEEE80-2000-example-b4...... 39 Figure 41: Adding Multiple Ground Rods- Screen 1.................................................................... 40 Figure 42: Adding Multiple Ground Rods- Screen 2.................................................................... 40 Figure 43: Adding Multiple Ground Rods- Screen 3.................................................................... 41 Figure 44: Adding Multiple Ground Rods- Screen 4.................................................................... 41 Figure 45: Adding Multiple Ground Rods- Screen 5.................................................................... 42 Figure 46: Adding Multiple Ground Rods- Screen 6.................................................................... 42 Figure 47: Adding Multiple Ground Rods- Screen 7.................................................................... 43 Figure 48: Adding Multiple Ground Rods-Screen 8..................................................................... 43 Figure 49: Adding Multiple Ground Rods - Screen 9................................................................... 44 Figure 50: Adding Multiple Ground Rods - Screen 10................................................................. 44 Figure 51: Adding Multiple Ground Rods - Screen 11................................................................. 45 Figure 52: Adding Multiple Ground Rods - Screen 12................................................................. 45 Figure 53: Adding Multiple Ground Rods - Screen 13................................................................. 46 Figure 54: Adding Multiple Ground Rods - Screen 14................................................................. 46 Figure 55: Adding Multiple Ground Rods - Screen 15................................................................. 47 Figure 56: Plotting 3-D Potential and Equipotential Couture lines – Screen 1 .......................... 47 Figure 57: Plotting 3-D Potential and Equipotential Couture lines – Screen 2 .......................... 48 Figure 58: Touch Potential and Equipotential lines .................................................................... 48 Figure 59: Touch Potential and 3D Graph .................................................................................. 49 Figure 60: Allowable Touch and Step Voltages ........................................................................... 49 Figure 61: Calculate Allowable Touch and Step Voltages........................................................... 50 Figure 62: Potential Along the Axis Calculation – Icon .............................................................. 50 Figure 63: Potential Along the Axis Calculation – Mouse Shape ................................................ 51 Figure 64: Potential Along the Axis Calculation – Define an Axis.............................................. 51 Figure 65: Potential Along the Axis Calculation – Define an Axis Continuation........................ 52 Figure 66: Potential Along the Axis Calculation – Step Potential Plot ....................................... 52 Figure 67: Multiple grounding systems........................................................................................ 54 Figure 68: Report for Multiple Grounding................................................................................... 55

Note: ‰

You can view this manual on your CD as an Adobe Acrobat PDF file. The file name is: Advanced Substation Ground Grid

Ground_Grid_Design.pdf

You will find the Test/Job files used in this tutorial in the following location: ‰ C:\DesignBase\Samples\GG3D = Advanced Substation Grounding Test Files:

IEEE80-2000-EXAMPLE-B1, IEEE80-2000-EXAMPLE-B2 IEEE80-2000-EXAMPLE-B3, IEEE80-2000-EXAMPLE-B4 IEEE80-2000-EXAMPLE-B2-SLANTED

ALL RIGHTS RESERVED COPYRIGHT 2008

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Advanced Substation Grounding Grid

1. ADVANCED SUBSTATION GROUNDING GRID DESIGN CAPABILITIES, FEATURES AND FUNCTIONS

                      

R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R

IEEE 80 (2000 & 1986), IEEE 665 Modeling, and IEEE 80/IEC 490 for Safety Analysis English or Metric Units Ease of use and visual design of grounding system Fast and Accurate Analysis of complex and large grounding grid assembly Grid/Rod/Profile Wizards to Set Up Initial System Rectangular, Square, or Custom Grid Shapes and 3D Plots Optimize Number of Conductors and/or Rods Equal or Irregular Conductor Spacing Parallel or Arbitrary Oriented Run of Conductors Rods & Conductors of any shape, size and in any 3-D Direction (Vertically driven or Slanted) Built-In Library of Rods and Grids Multi Layer Soil Model Development of the Two Layer Soil Resistivity Model Based on the Wenner Measurement Techniques Using Advanced Optimization Method Passive and Return Grids and Pipe Model User Specified Fault Current Safety Analysis Including Surface Materials Based on Body and Exposure Time Parallel Resistance of Tower Footing and Substation Transformer Grounding Computation of Ground Grid Assembly Resistance, Ground Potential Rise, Step, Touch and Mesh Voltages Touch and Surface Potential Analysis Data Entry for Earth Model, Rods and Grids in Spreadsheet Format Current Decrement/Division Factor Move the ground grid assembly upward/downward/left/right with a click of mouse 3-D, Cross Sectional, and Top Graphical Interface Views Ability to Analyze the Potential Rise for Each Ground System Including Neighboring Passive Grids or Rods Calculation of Tolerable Step and Touch Voltages on the Basis of the Person Weighing, fault duration and soil resistivity Touch and Potentials within user defined irregular shapes Identification of the location of the worst touch potential (i.e. maximum touch) Identification of the location of the worst absolute potential (i.e. maximum absolute potential) Export absolute/touch/step potentials in 2-D and 3-D to Excel 2-D and 3-D touch, step, & absolute potential graphs 2-D and 3-D touch, step, & absolute potential graphs in an irregular user defined area Graphical and Color-coded display of Danger Areas Step and Touch Voltage Profile on user-defined area or along a specified path User-Defined Thresholds for Danger Area Evaluation User-Defined Color Coding for Graphical Safety Analysis Powerful Zoom Feature Zoom in/out to visualize details or global views Modeling of ground grid & rod conductors assembly & automatic setup of self & transfer impedance matrix Grid Conductor Current Displacement Using Matrix Analysis Ground Resistance Calculated Using Conductance Matrix Comprehensive Report for Grid and Rod Configuration

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Advanced Substation Grounding Grid

  

R Comprehensive Report for Surface Potential Analysis Featuring Station Data and Currents Diffused R R R R

to Ground by the Grid Elements Danger Point Evaluation Report Viewer Range Checking for Simulation Parameters Advanced numerical method for efficient and accurate conductance matrix calculations

2. FOREWORD This discussion assumes that the user is a Professional Engineer familiar with the AC Substation Ground Grid Design concepts that affect the electrical distribution systems performance during Ground Fault conditions. Determination of validity of the results, and whether the program is applicable to a system, is the user's responsibility. This program is undergoing continuous development, and EDSA is determined to make this program as comprehensive and easy to use as possible. Additional analyses capabilities will be made available as they are developed. Any comments, suggestions or errors encountered in either the results or documentation should be immediately brought to EDSA's attention. You should read and be familiar with ANSI/IEEE standards and run all the examples in the manual before building your own job file and run the program.

3. ...