The design concept of equipotential ground grids in substation building as well as connection of gis enclosures to. One type of substation is an open air substation, which is the traditional design that uses the insulation properties of ambient air as an external insulating medium. The substation site must be reasonably central to the distribution area to be served. The purpose of a ground mat study is to provide for the safety and wellbeing of anyone that can be exposed to the. Also, the grounding system of the building in gis indoor substation has to. Design of grounding system for an electrical substation. Ge provides a full range of gasinsulated substations gis for utilities and industries worldwide. It accounts for the impedance of the conductors making up the grounding system and allows currents to be injected into the.
A variety of advanced solvers provide adapted approaches to. An urban gis substation grounding system design is a complicated task in. This is largely due to the fact that gis systems are significantly smaller and weigh less despite the gas weighing more than air. By means an iterative process, new elements are added to the grounding. Design of earth grid for a 3311kv gis substation at a high. This voltage, gpr, is equal to the maximum grid current times the grid resistance. This bulletin is an update and revision of previous rea bulletin 651, design guide for rural substations revised june 1978. Gis substation grounding, earthing, software ses india. Earthing system is made of a mesh of buried bare copper cable, with additional earth rods, and shall be calculated, being recommended to use ieee std. Design of earthing grounding system in a substation grid. The five volume report comprises the user manual, installation, and validation manual and an applications guide for the sga substation grounding analysis software package.
The main ground grid design is performed according to ieee std. Substation at a high soil resistivity site using cymgrd software. An ebook reader can be a software application for use on a. The maximum electrical potential that a substation grounding grid may attain relative to a distant grounding point assumed to be at the potential of remote earth. Moreover, the software output also has been seen for crosschecking of theoretical calculation. Research on lightning intruding waves in 220 kv gis substation. Innovative construction uses bricks and mortar to create a spiral line building smart bricks duration. Grounding must be taking into account to protect passersby during a shortcircuit in the transmission system 7. Safety design of ground grid in distribution substation gmsarn. Gis highvoltage gas insulated switchgear substations. In the video we use the soil resistivity analyzer to determine a soil model from wenner resistivity measurements, then proceed to import our grounding systems for the substation, steel factory, and adjacent.
Grounding of high voltage substations is a very important subject in electric power technology since it is decisive when it comes to touch and step voltages that will arise within a substation area during an earth fault. The methodology takes the reference from the ieee std. The gis substation has most of its electrical structure contained in sealed tubular enclosures. Before the design of the grounding system begins, soil resistivity measurements need to be taken at the substation. The problem is formulated as a mixedinteger linear. Gis solutions for power generation and transmission services. The main purpose of this work is to design the grounding system for 400kv darbhanga gis substation. Electrical engineers use powertools to perform harmonic analysis, transient stability analysis, short circuit analysis, and to determine demand load, voltage drop, arcflash hazard analysis and protective device coordination. The resulting earthing types are displayed both on the one line diagram and for the various connected cables. Local control cabinet lcc in gas insulated substationgis.
With gis experience spanning 50 years across a wide range of industries and applications, ge is a leader in the. Conventional switching and gis substations with or without transformers. Design and analysis of ground grid system for substation. 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. In smaller distribution substations the usually acceptable range is from. Grounding design calculations part seventeen electrical. We provide sustainable solutions that help our customers effectively manage electrical, hydraulic and mechanical power more safely, more efficiently and more reliably. These electrical substation platforms allow multiple workers the ability to access control boxes for repairs or maintainence without the risk of a stand alone ladder. 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. Grounding and soil structure cdegs software package. Importance of an adequate substation ground grid design. These substations are generally constructed in an open, nonenclosed, nonatmospherically controlled environment and can be built either outdoors or indoors. Pdf grounding system design in electrical substation. If the system has 50 ka total connected load what will be the fault current.
Optimized design of substation grounding system using newly. The portfolio includes gis solutions from 60 to 800 kv, along with secondary products to maximize switchgear and network operation. The proper grounding of a substation is essential and very important for the following two reasons. Gis substation are considered safe and complies with all recommended guides gis pdf\generallayout gis. Grounding system, design criteria, calculation note. The cross section of the buried cable should calculated in accordance with the value of the phasetoearth short. The reader is well justified in wondering whether the best approach might be.
Cdegs c urrent d istribution, e lectromagnetic interference, g rounding and s oil structure analysis is a powerful set of integrated software tools designed to accurately analyze a variety of electromagnetic related problems encountered in all industries involving electric networks. Design and analysis of substation grounding grid with and. Substation grounding software eaton s mission is to improve the quality of life and the environment through the use of power management technologies and services. High voltage substation grounding has previously been an experienced. System grounding and earthing types analysis software etap. For most transmission and other large substations, the ground resistance is usually about 1.
With multipoint grounding and the resulting many parallel paths for the current from an internal fault to flow to the substation ground grid, it is easy to keep the touch and step voltages for a gis to the safe levels prescribed in ieee 80. Analysis of vfto across bushing in 765kv gas insulated substation using emtp software. The paper describes aspect of designing earth mat for gis substations with high. Nov 30, 2014 3d substation design and modelling, south africa.
Guidelines to properly designed substation grounding system eep. In a properly designed system, this gradient should not exceed the limits that can be tolerated by the human body. Esgsd is preliminary developed in order to assist the engineers in the design of substation grounding system. Gis indoor substation normally occupies only 1025% of the land required for conventional ais. The robust and low maintenance gis based design minimizes the substation s footprint by as much as 70 percent, enabling it to be installed indoors, in busy urban areas and in harsh environments. For example, for a small substation with some transformers, if there is a fault in the system how will the fault current flow into the grounding system. Gis solutions for power generation and transmission services balancing the need to develop new markets, improve system reliability, and reduce operation costs is the greatest challenge for todays utility decision makersa challenge that is successfully met with esri s geographic information system gis software. Optimal design of substation grounding grid based on. Earthing design service utilising cdegs software package earthing system audits ea technologys earthing system audit provides an essential assessment of the earthing system in and around substations and other power assets, along with the associated maintenance procedures. Design of earthing system of a 400230 kv gis substation with high. And how would i calculate what percentage of the fault current will flow into the ground.
A grounding grid is designed with the capacity to minimize the very fast transient overvoltage generated during switching operations in a gas insulated substation gis. Substation system software applications cyme grids eaton. Cdegs worldwide leader in grounding, earthing, lightning. Substations may also be owned by manufacturing, industrial, or large commercial customers. Pdf safety performance evaluation of fence grounding.
Substation grounding software is not a substitute for autocad. 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. Design and simulation of a grounding grid for gis substation. Substation grounding study specification introduction. The substation grounding system is an essential part of the every electrical system. Introduction the design consideration of substation grounding is important for providing low resistance path to ground, to allow. Engineering guide nccses gas insulated substation grounding analysis. A good grounding system provides a low resistance to remote earth in order to minimize the ground potential rise.
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. Important formulas for designing a substation grid earthing system. These conductive enclosures, underground grounding grid and above ground bus bars, all contribute to the grounding system. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software mithun mondal, dr r. Substation grounding programs technical report osti. Cdegs current distribution, electromagnetic interference, grounding and soil structure analysis is a powerful set of integrated software tools designed to accurately. Furthermore, the analysis of software graph is done by fdm finite difference method which is one of the mathematical solutions and it shows that how the graph generates in software. Home technical articles gis vs ais substation earthing aeg gis gas insulated switchgear up to 420 kv compressed sf6 gas used in mv and hv switchgears as an insulating medium has led to the development of compact gasinsulated substation cis technology figure 1. First, it provides a means of dissipating electric current into the earth without exceeding the operating limits of the equipment. Comparison of ais and gis based on grounding design a. With ses, you input the total fault from your fault analysis program, along with data on shield wires, tower grounds, source substation ground resistance, etc. Thus, measurements should be made at multiple locations within the site.
Introduction he optimization of the design of substation grounding grids placement of gis an issue that has assumed an increasing importance, since it seeks to reduce the amount of conductive. Substation engineering ais and gis substations beta. Easypower is partnering with the industryleading grounding and emi analysis expert company, sint ingegneria, which offers a software package to analyze and design grounding, lightning and electromagnetic interference problems by focusing on its powerful and yet affordable grounding analysis software packages, xgslab. Gis technology originated in japan, where there was a substantial need to develop technology to make substations as compact as possible. Substation grounding software is a utility program accessible through the software menu structure, that allows the user to alternate between the autocad and substation grounding software environments. Cymgrd is a software program specialized in the substation grounding mat design. Design of grounding system for gis indoor substation.
So the software should be capable of meddling above ground and below ground structures. Our indepth knowledge of the power value chain, as well as grid codes and utility practices in use around the world, enable us to provide turnkey. All rus borrowers rus electric staff effective date. Flow of the earth system, cause voltage gradients ground.
Index terms conductor material saving, ground rods, optimization of substation grounding grid, sveraks method. The design concept of equipotential ground grids in substation building as well as connection of gis enclosures to main ground grid is described. At the beginning of the gis technology, the grounding design was based in the classical approach of limiting the power frequency enclosure potentials to safe levels based on the maximum expected faultcurrent conditions. Therefore, the grounded area of gis indoor substation is also reduced.
Ieee guide for safety in ac substation grounding ieee std 802000. Electrical and physical arrangement, grounding, testing. A reader responded with the question of whether the best approach might be to ignore the rebar bonding. Basics of designing power substations 3 phase associates. The grounding system design for gis indoor substation is proposed in this paper. Not long ago i wrote an article on substation grounding for electrical business that raised the issue of whether one should interconnect the building reinforcing steel with the station ground electrode. Userfriendly data entry, efficient analysis algorithms and powerful graphical. Design of earth grid for a 3311kv gis substation at a high soil. During factory acceptance test fat, all the operations and logics from lcc are checked by customer.
In the tutorial, a substation grounding system is subjected to a fault and transfers the groundearth potential rise to the connected steel factory grounding system. The lightning intruding waves in 220 kv gis substation model was built by using atpemtp software, calculate the lightning overvoltages on electric equipment in substation with different running modes, different grounding resistance and lightning shielding failure. In the video we use the soil resistivity analyzer to determine a soil model from wenner resistivity measurements, then proceed to import our grounding systems for the substation, steel factory, and adjacent site entrance from an existing dxf. Since then, more than 40,000 gis bays have been installed in substations worldwide.
Before the software can aid the substation design engineer, the electrical single line and ground grid for the substation will have to be designed and modeled within the software. Then after the grounding design is done for identical 400kv ais substation and comparison made between both types of the substation for grounding design. How to calculate fault current in electrical substation. Here software named economical substation grounding system designer. Provide a safe and costeffective conceptual grounding system design for the substation by means of. This module can evaluate the estimate places for the danger voltage points in the grid and its. This computer program can be used directly to determine the grounding cable size requirements for. Following snip shows various results gis substation using xgslab grounding design software. Review of substation grounding practices, safety and. The maximum touch voltage within a mesh of a ground grid. A gas insulated substation gis is a high voltage substation in which the major structures are contained in a sealed environment with sulfur hexafluoride gas as the insulating medium.
This software is suitable for grounding systems of any size. Safe step and touch voltage criteria based on body weight defined in ieee std. Multigroundz and multigroundzplus software packages. This substation grounding course covers effective relaying and insulation of equipment. An effective substation earthing system typically consists of earth rods, connecting cables from buried earthing grid to metallic parts of structures and equipment. Three years later, mitsubishi electric constructed the worlds first 550kv fully gas insulated switchyard at the ohi nuclear power station, which is the largest nuclear power plant in japan. Provided the technician doesnt need to handle the gas itself, gis substations are quicker to install. The design of grounding grids for substations and buildings is a vital part of the overall power system infrastructure assuring constant power supply to consumers.
It implements theoretical concepts given in 9 in the software form. Cyme power engineering software and solutions substation. The robust and low maintenance gis based design minimizes the substations footprint by as much as 70 percent, enabling it to be installed indoors, in busy urban areas and in harsh environments. In 1973, it installed the first 500kv hybrid gasinsulated substation. Substation engineers must accurately assess the condition of grounding systems to ensure they are capable of dissipating additional fault current. Civil and electrical engineers need pointed analyses that assure installations are fully secure for personnel and also sound and economical construction, connection and operation of the grids along with proper equipment. Substation grounding training the electricity forum. This is a great advantage if compare with other grounding programs that the split factor is to be input usualy assumed. In this work the safety provided by several fence grounding techniques commonly used in high voltage installations is evaluated for a 15020 kv air insulated substation, a 400 kv stepup gis.
Figure 1 show shows the technical ideas of the gis intelligent lcc and photo 3 show an intelligent installed in a substation in china country. Stations with uniform resistivity throughout the entire area are rarely found. It may be used to make a new design for new grids or to optimize and enhance an existing one of any shape. This paper presents an accurate electromagnetic field theory method to model and analyze a realistic grounding system involving gasinsulated substation g.
Dc substation gis and lightening effects are not covered in this paper. Other advantage is that the program determine the worst case scenario after many automatic iterations usually located somewere in the line outside the substation. The soil resistivity test results will also be required as. Design of earth grid for a 3311kv gis substation at a. Distribution substations michigan technological university. Safety analysis for grounding system of two neighbouring. Installing a gis high voltage substation can be faster than installing its metalclad ais counterpart. Abstractthispaper describes the design ofan earthing system for agas insulated switchgear gis substation using cymgrd software.