Design of earthing grounding system in a substation grid. Powertech labs conducts ground grid assessments and studies, and facilitates different grounding related testing. Gsflow is a coupled groundwater and surfacewater flow model based on the usgs precipitationrunoff modeling system prms, modflow2005, and modflownwt. This paper will present ground potential rise gpr causes, effects, variations in the values gpr in high voltage substations. Substation at a high soil resistivity site using cymgrd software. Gsa grounding system analysis for regular application applicable in most. Standard equations are used in the design of earthing system to get desired parameters such as touch and step voltage criteria for safety, earth. Introduction in designing and construction of an electric substation, one of the most important issues that must be considered is designing of protective system to the earth. For comparison of the calculations done by both techniques, the obtained results are shown in table 3. Pdf upgrading existing grounding system for substation. Advanced power concepts grounding analysis and design software. It is clear that the ground potential rise gpr as well as. Our 2 thick ground grid is perfect for all sorts of projects.
This software is suited for grounding studies of electrically small installations where circulating currents within the grid are negligible, where. Advanced grounding concepts grounding analysis and. The ground grid system ggs module included in latest version of etap i. Pdf soil resistivity and ground resistance for dry and wet soil. The ground grid will be for a substation with a low side of 34. Nov 15, 2010 this is the first time that ill be doing a calculation on the ground grid study of a plant. The ground fault current in this study is assumed to be 7 ka. The presenter brings a case where the soil, site environment, and power system properties present challenges that can be solved with the use of a software package.
Called the etap tech support, but could not get information. Fast analysis of irregular largescale renewable ground grid application. Because the grid model is not perfectly aligned with the ground there is a whole field of study on this, there is distortion depending where you are on the grid. Nov 08, 2014 design analysis and optimization of ground grid mesh of extra high voltage substation using an intelligent software abstract. A rectangular grid configuration with dimension 150 m. Standartpark easypave grid 2 depth permeable paver system 88,000 lb load rated diy rv pads, driveways, parking, and more. Software development of optimal substation ground grid. A grid scale factor can be computed and the combination of the grid and elevation scale factors is known as the combined scale factor or csf. This paper also details a ground grid integrity testing method that can be deployed to track the health of the ground grid. Also he is involved in the study of software applications in the. Furthermore, amount of current that may flow through.
Ground grid study windturbinesarefine electrical 18 jan 10. Ieee guide for safety in ac substation grounding limits. The main objective of a substation grounding study is to design safe. Power substation design calculations a checklist of 18. Difference between the symmetrical current wave and the actual current wave during a power system transient condition, see fig 2. Classical grounding studies low frequency, equipotential systems. Just to let you know i only had to take my airframe and general. Location of maximum touch and step potential can be known by fem method from the plots. Soil measurement data based on wenner fourpin method. Made from polyethylene material which lasts the test of time, and will hold any type of aggregate or filling you desire to fill. The maximum touch voltage within a mesh of a ground grid. Tylavsky, chair john undrill raja ayyanar arizona state university. The use of a swage ground connection improves field safety, facilitates a better quality installation, improves constructability and project efficiency with time and labor savings in all weather site conditions. Computer aided design of transformer stations grounding.
Safety assessment of a substation ground grid with a software. Optimal substation ground grid design based on genetic. We use skms stateoftheart groundmat software module. Gpr studies use a series of calculations to determine step and touch voltages in accordance with specific standards. From cdegs the concrete foundations reinforcement bars are generally connected to the grounding grid and may improve the grounding performance of the grid. Grounding grid calculations in etap mike holts forum. Development of earth parameter estimation software and its.
The indices for ground grid safety are expressed and grounding grid analysis had done with the cymgrd software. An extensive study of earthing grids using safegrid software designed for determining performance of grids of arbitrary geometrical configuration in two layer soils has been undertaken. Choose the type of study you want to dolike basic bible study or sermon prepand logos walks you through each step. The grounding systems described in this study consists of a 110 x 80 m grounding grid plus additional ring 5m away from grid. To consider substation expansions, the ground grid is examined using software and, if required, extended to meet the ground potential rise gpr, touch and. The steps to create a ground grid system presentation ground grid design are as follows.
Dupont groundgrid ground stabilization system is a geotextile grid used for ground stabilization in landscape and construction projects. Is using cdegs for design of the substation earthing. A comparison of ground grid mesh design and optimization for. Eligible to design and analyze the ground grid area up to 10,000 square meters. I am performing a ground grid study using etap, but am not able to understand how it works. I scored 96% on my airframe and a 98% on my general. Sep 12, 2014 overview on etap capabilities in ground grid system design and analysis using ieee 80 standard and finite element method fem. Recommends an optimallydesigned safe ground grid that uses accurate modeling techniques, and enables possible material and labor savings while meeting all ieee 80 safety requirements. There are six distribution feeders on the low side coming from the wind farm generation and the step up transformers are wyewye.
Standartpark 2 thick geo grid ground grid polyethylene 160 sq ft 1885 lbs per sq ft strength. The software is powerful and has a lot of capabilities but is not the most intuitive when it comes to the user interface compared to some other programs. At substations, grounding grids serve a dual purpose of providing currents with a safe path to earth under normal and fault conditions without exceeding the operating tolerances of station equipment. In 2009, uzunlar and kalenderli used cymgrd software to make a computer model for analysis of grounding systems conforming to ieee standards.
If done the first time, clicking the new study case button will create a copy of the default study case. Logos reads all your books instantly, delivering just what you need at each step in your bible study. It is designed to help optimize grid design or reinforce existing grids of any shape. Eatons cymgrd software is a substation grounding grid design and analysis program specially developed to help engineers optimize the design of new grids. Soil resistivity and ground resistance for dry and wet soil. Analytical methods for earth surface potential calculation. The plant which im doing the study on is definitely bigger than that. Pvsyst is a pc software package for the study, sizing, simulation and data analysis of complete pv systems. Safety assessment of a substation ground grid with a software package this presentation covers the case study of a substation ground grid safety performance. For the love of physics walter lewin may 16, 2011 duration. These studies also help to determine grid hot spots enabling the. The maximum touch voltage experienced while standing within a mesh of a ground grid and touching a grounding object.
Pdf design analysis and optimization of ground grid mesh of extra. Ground grid systems software capabilities fast analysis of irregular largescale renewable ground grid application. Development of earth parameter estimation software and its application in the design of ground grid. Dupont groundgrid ground stabilization 4 x 25 small grid. The single lineto ground fault current is actually divided and redivided as it passes through the grid, reducing the actual current at any given point in the system. Design analysis and optimization of ground grid mesh of extra. Dec 11, 2015 for the love of physics walter lewin may 16, 2011 duration. The purpose of this paper is provide knowledge about the gpr, substation grounding grid and step and touch potentials. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software mithun mondal, dr r. Integrated software for power engineers the ptw study case manager is the ultimate tool for storing and comparing study results. Etap does this by creating a duplicate copy of the existing study case. In high and medium voltage air insulated substations ais the electromagnetic field, which causes are the static charges of bare cable and conductors and by the atmospheric conditions surges, induce voltages at nolive parts of the installation that create potential differences between metallic parts and ground and also between different points of. Optimal design of substation grounding grid based on genetic.
Short circuit analysis short circuit software etap. Design and analysis of substation grounding grid with and. Analyzers, plots and reports allow for quick determination of the worstcase fault current device duty. It uses a generalpurpose finite element algorithm for potential analysis and graphical facilities to validate ground system. Grounding, electromagnetic fields, interference and lightning. Grounding grid consists of rectangular cross section fezn. Jr, arkansas northeast college the software was a fantastic study guide. Figure 3 illustrates the 3 dimensions 3d and contour profile for the case r014p16. Skm groundmat is a program for substation ground grid design and analysis. Optimal substation ground grid design based on genetic algorithm and pattern search by qianzhi zhang a thesis presented in partial fulfillment of the requirements for the degree master of science approved november 2014 by the graduate supervisory committee.
During my simulation of the ground grid study, i noticed that the maximum grid area that etap can calculate is 10,000 sqm. Flow of the earth system, cause voltage gradients ground. About applying a ground to grid correctionhelp arcgis. Overview on etap capabilities in ground grid system design and analysis using ieee 80 standard and finite element method fem. Simply expand the threedimensional honeycomb structure, place it on your project surface and fill with gravel, soil, sand or other mineral infill to create a strong and stable surface. Standartpark 4 inch thick geo grid ground grid polyethylene. The study of each of the mentioned parameters has been used to develop weight factors based on the effect of each parameter upon the grounding grid performance represented in grounding grid.
Here, two layer soil models are considered with upper and lower layer soil resistivity of 400 ohmm each is used. Display any combination of variables from multiple studiescases on a single graph. The new study case button initializes the creation of a new study case. Is a module for earth grid calculation and design in the frequency domain, including soil analysis and represents the state of the art of grounding software.
Mathematically, the actual fault current can be broken into two parts, a symmetrical alternating component and a unidirectional. The computation program modules resap, malt and fcdist are used for this study. Communicate results more efficiently with graphical comparisons. We use skms stateof theart groundmat software module and accurately determine the touch and step. Advanced power concepts po box 49116, atlanta ga 30359, phone fax. The 500kv substations are important for power system in pakistan.
They cover large area meeting the power requirement of whole power system. The etap software version 12 is used for modeling and analysis of network. Etap short circuit software makes it easy to go from selecting elements, from the comprehensive library of short circuit current ratings, to performing dozens of different types of short circuit analysis. My main problem is how to enter data in the ground grid and how to link the ground grid to the single line. Annex c of the standard uses a graphical method to approximate the grid current. Integrated grounding system analysis program for windows. A surveyor may measure angles on the ground relative to any of several definitions of north. Design of earth grid for a 3311kv gis substation at a.
The difference in potential between metallic objects or structures within the substation site that may be bridged by direct handtohand or handtofeet contact. Ground potential rise gpr is a concern in the design of substation grounding grid. Install mesh grounding system as shown in figure 9 to create an equipotential surface. Made from polyethylene material which lasts the test of time, and will hold any type of aggregate or filling.
Once done, the new study case will be available on the dropdown menu. If you are also using the smart ground meter for measurements that data also integrates into the program as well. The open circuit handtofoot voltage during a ground fault. Ground grid systems software ground grid design ieee. It uses a generalpurpose finite element algorithm for potential analysis and graphical facilities to validate ground system efficiency. This software is suited for grounding studies of electrically small installations where circulating currents within the grid are negligible, where above ground structures and busses are not relevant for the study and where extensive external metallic infrastructure does not exist close to the substation. Review of substation grounding practices, safety and. A ground grid mat study will determine if your substation grounding grid design is safe and will limit the touch and step potential to values below the ieee 80 standard ieee guide for safety in ac substation grounding limits. Ground grid systems software ground grid design ieee 80. You may set constants the ground to grid correction for directions and distances so that the software can correctly convert between the ground and grid measurements. Aug 02, 2017 an extensive study of earthing grids using safegrid software designed for determining performance of grids of arbitrary geometrical configuration in two layer soils has been undertaken.
This voltage, gpr, is equal to the maximum grid current times the grid resistance. The concrete itself, being a very hygroscopic material, tends to attract moisture from the neighboring soil and will eventually acquire to same resistivity as the soil it is in contact with. International journal of engineering trends and technology. The analysis of mesh is carried out using both ieee 802000 and finite element methods for the evaluation of important ground grid mesh parameters. It is suitable for grid connected, standalone and dc grid public transport systems, and offers an extensive meteorological and pvcomponents database.
The cymgrd software is a substation grounding grid design and analysis program specially developed to help engineers optimize the design of new grids and reinforce existing grids, of any shape, by virtue of easy to use, builtin danger point evaluation facilities. Detailed short circuit calculation using etap pac basics. Access rights manager can enable it and security admins to quickly analyze user authorizations and access permissions to systems, data, and files, and help them protect their organizations from the potential risks of data loss and data breaches. Modflowusg uses an unstructuredgrid approach to simulate groundwater flow and tightly coupled processes using a control volume finitedifference formulation. Cyme power engineering software the cyme power engineering software is a suite of applications composed of a network editor, analysis modules and usercustomizable model libraries from which you can choose to get the most powerful solution. Extensive study of earthing grids electrotechnik pty ltd. The study confirms work by dawalibi and mukhedkar undertaken using similar software called cdegs. The voltage between local soil and a grounded object that extends. By using your testprep software and audio files i am currently carrying a 4. Grounding design calculations part ten electrical knowhow.
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