Design and analysis of substation grounding grid with and without considering seasonal. The rod length is varied to determine the influence of rod length on gpr, furthermore, when the soil structure is. The electrical grid transmits power over wires to our houses, and our bryan cockfield has covered it very well in his electrical grid demystified series, but what part does the earth ground play. Over the years grounding design terms and definitionsprocedures have been developed. Abstract the main purpose of this paper is to acquaint the reader with various types of grounding systems prevalent in an electrical substation and their importance. Soil testing and soil data is typically provided by others. Electrical 20142018 sardar vallabhbhai institute of technology, vasad vadodara, india abstractthe paper depicts about design of ground grid system for 6611kv rectangular substation.
Covers general issues related to site design, foundation design and control house design. Access above ground level shall be from mobile or fixed platforms though the latter may be accessed by. The following data given in the table is considered for the substation ground grid design table 1. Design of earthing grounding system in a substation grid. Optimized design of substation grounding system using. Substation grounding design challenges and lessons learned. Modeling and simulation are carried out on the current distribution electromagnetic a. For comparison of the calculations done by both techniques, the obtained results are shown in table 3.
The following steps were established by the ieee standard 802000 for the design of the ground grid. But the generation plant is right beside the new substation. This paper presents a safety design of ground grid for a practical 120 mva, 11524 kv substation grounding grid system in mea. Pdf design of groundmat for 11kv substation using auto grid pro. I am trying to design a ground grid, but i need to add a ground well a ground. Clearing times for single line to ground and double line to ground faults. Hence substations in general can be considered as heart of overall power system. Several parameters define the geometry of the grid, but the area of the grounding system, the conductor spacing, and the depth of the ground.
This bulletin is an update and revision of previous rea bulletin 651, design guide for rural substations revised june 1978. Chapter 2 explains ground fault currents and chapter 3 covers grounding conductors. Ground potential rise gpr the substation earth grid is used as an electrical connection to earth at zero potential reference. This bulletin provides a basic design guide and a reference tool for designing rural substations. Subsequent chapters cover the types of voltages that must be addressed and how to design a ground grid. This paper presents performance analysis of actual step and mesh voltages of a substation grounding system under the variance of length and number of ground rods. Welldesigned grounding system is very much essential as far as the safety of the crew and the substation equipments are concerned. Abdelhadi ragab introduction objectives of a grounding system may be summarized as follows.
In this paper a procedure of transformer grounding system design and spatial distribution of touch and step voltage on the ground surface level is analysed by using the cdegs current distribution electromagnetic interference grounding and soil structure analysis software. The substation grounding system is an essential part of the every electrical system. The following sitedependent parameters have been found to have substantial impact on the grid design. Ground grid systems software ground grid design ieee. Ground potential rise also mainly depends on the length and numbers of ground rods and grid spacing. For calculation of this current grid resistance and fault resistance are assumed to be zero. Ground grid design ground grid design poutchi electrical op 9 apr 08 10. Therefore, this number should be as close to the realworld. 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 grounding system for a substation is complex due to the involvement of numerous parameters. Design of groundmat for 11kv substation using auto grid pro.
International journal of engineering trends and technology ijett volume 15 number 8 sep 2014. Fence is outside of ground grid area, but is not connected to the substation ground grid. Computer aided design of transformer stations grounding. Wherever two of these threads of light intersect, a vortex is formed. The comparison between theoretical values and experimental values for various types of grounding grid performance at fixed depth is carried out 5,6. 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.
Pdf design and analysis of substation grounding grid. Covers the design of the ground grid for safety and proper operation. Fence is outside of ground grid area and is connected to the substation ground grid. Design and analysis of ground grid system for substation. The size of the soil model is calculated as a multiple of the grounding grid size and is closely dependent on the accuracy of calculations. My question is how can i measure the resistivity of the area as there is an existing plant right there. The epr is caused only by the current injected into the ground by the earthing grid. You can see this grid as a fine lattice of light pulsations. Ground grid systems software ground grid design ieee 80. Cost effective grounding grid design for substation soni m, dr. In this video, i mentioned the basic steps for designing power substation grounding grid using custom codeprogram made under matlab environment. Ieee guide for safety in ac substation grounding ieee std.
Design and analysis of substation grounding grid with and. Optimal substation ground grid design based on genetic algorithm. Cold sites do not require any special design principles and the touch and step voltages are deemed to be safe by inference. High voltage electronic system area is to bereferred as substation. Kasirawat safety design of ground grid in distribution substation. We use skms stateoftheart groundmat software module and accurately determine the touch and step potentials. These substation grounding design can be designed to regulate the system, to switch or changing the voltage of electricity in and out of a system. Etap model for earth mat design etap model for earth. The proper grounding of a substation is essential and very important for the following two reasons. In contrast, the topology of grounding grid is based on substation equipment layout and therefore it may not necessarily be equally spaced grid as.
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. Covers the design of bus support structures and connectors. Omega red group are the uk market leaders in the specialist design, supply, installation, testing and maintenance of electrical earthing and lightning protection systems. Substation grounding grid design and analysis module is specially designed to help. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software. From the past, ground grid design without rods and with rods was carried out. Chapter 1 is a general discussion of grounding issues. Grounding design calculations part sixteen electrical knowhow. Earthing design of 11kv and 33kv rural substations in the uk.
Pdf this study presents an advanced methodology and a computer model for analysis of. The fence is connected to a separate grounding conductor. Oct 30, 2012 in this video, i mentioned the basic steps for designing power substation grounding grid using custom codeprogram made under matlab environment. Over the years grounding design terms and definitionsprocedures have. I am working on a ground grid for a new substation. Two other important design parameters, which depend upon the value of the ground. Shows the basic shock situations for the substation ground grid. Integrated grounding, equipotential bonding and lightning. Whitepaper substation grounding identifying and implementing. Therefore, the design is based on single line to ground fault current.
Ground grid, ground potential rise, step voltage, touch voltage 1 introduction metropolitan electricity authority mea is an electric. Optimized design of substation grounding system using newly developed ieee compliant software issn. Grounding grid integrity energiforskrapport 2017405. Below is the sequence of procedure to design the ground.
This voltage, gpr, is equal to the maximum grid current times the grid resistance. The uniform and two layer soil structure for substation ground grid design is mostly used in india 4,5. Successful operation of entire power system depends to a considerable extent on efficient and satisfactory performance of substations. Some of them are already fully activated, while others still await their time. Grounding grid design using matlab for power substations. 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.
Fault current computations may be obtained from the owner or calculated by ees consulting. Design guide for rural substations usda rural development. Jul 12, 2010 the purpose of this paper is to report a new test method and make a recommendation to improve the procedures according to the findings. Optimized design of substation grounding system using newly. National grid substations technical specification ngts 2. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software mithun mondal, dr r. Etap facilitates an engineer to carry out ground grid design as well as analysis with considerations specified in various standards such as ieee801986, ieee802000 and ieee6651995. International journal of engineering trends and technology. Earth grid commissioning for new electrical systems routine earth testing for preexisting systems high voltage safety compliance audits accreditations asnzs2067 asnzs3007 1016 0 267 373 earth grid design and testing. The maximum touch voltage within a mesh of a ground grid. Pdf three dimensional grounding grid design researchgate. Substations volume x grounding a pdh online course. The test method involves measurement of high voltage substations earth grid impedance, by utilization of a variable frequency current source and frequency selective measurement techniques. Modeling and simulation is carried out on the current distribution electromagnetic interference grounding and soil structure cdegs program.
Flexible design methodologies allow for quick autodesigned layouts or very detailed schemes. Ground network design algorithm block diagram in figure 1 is the sort earthing studies. Performance analysis of actual step and mesh voltage of. The ground grid systems module enables engineers to quickly and accurately design and analyze ground protection. It would be conservative to assume no existing power plant ground grid, as far as the design of the new substation grounding is. Index terms conductor material saving, ground rods, optimization of substation grounding grid, sveraks method. Design of grounding system for an electrical substation. High efficient multicore parallel calculation allows fast analysis of irregular largescale renewable applications. Determination of maximum grid current a single line to ground fault is more common and causes more fault current as compared to a double line to ground fault. Cost effective grounding grid design for substation. The ergon energy design philosophy is to provide substations. Ees consulting provides ground grid design as part of the substation design based on ieee standard 80. Moreover, this software also provides finite element modeling fem of the ground grid for detailed analysis. Similar designs are used in substations in the grid.
Optimal substation ground grid design based on genetic. In particular, protection relay data including characteristic curve, overcurrent setting, time multiplier setting, instantaneous. These revisions may include smaller conductor spacing, additional ground rods, and use of closer. I am trying to design a ground grid, but i need to add a ground well a ground rod that is driven deep enough till it is in water, e. First, it provides a means of dissipating electric current into the earth without exceeding the operating limits of the equipment. High voltage substation earth grid impedance testing. This connection, however, is not ideal due to the resistivity of the soil within which the earth grid is buried. Conductors a substation earthing grid will consist of a earthing system of bonded cross conductors. The comparison between theoretical values and experimental values for various types of grounding grid performance at fixed depth is carried out. Power station grounding grid design using field methods 39 parameters as the construction materials of the grounding grid. 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.
Underlying the b grid is another grid system called the a grid or master grid. Jul 25, 2017 the electrical grid transmits power over wires to our houses, and our bryan cockfield has covered it very well in his electrical grid demystified series, but what part does the earth ground play. Calculationofimportantdesignparametersforgroundingsystemsi. Mortezaeei 2 1 electrical engineering department, seraj higher education institute, tabriz, iran, n. Connections from equipment and structures to ground grid. Etap model for earth mat design etap model for earth mat design.
Connections used in substation grounding, new york. Effects of ground grid configuration of two neighbouring. The problem is, when i do this it seems that the soil resistivity. Calculationofimportantdesignparametersforgroundingsystemsinsu. Design and analysis of ground grid system for substation using etap software and fdm code in matlab deep b. Grounding design calculations part sixteen electrical.
A vertical rod is more effective electrode than a horizontal rod. Student 2,3assistant professor 1,2,3 department of electrical engineering 1, 2, 3 g. The grounding grid was installed upon the construction. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software article pdf available april 20 with 3,151 reads how we measure reads. Bs 7354 code of practice for design of highvoltage openterminal substations. Substation grounding grid design and analysis module is specially designed to help engineers optimize the design of new grids and reinforce existing grids, of any. Abstract substation grounding is a critical part of the overall electric power system. Design of grounding grid according to ieee standards. Safety design of ground grid in distribution substation. Integrated grounding, equipotential bonding and lightning protection in smart grids and smart buildings a multifaced approach. Identifying and implementing costsaving design practices 3 fault magnitude the magnitude of the fault current into the earth via the substation ground grid is directly proportional to the ground potential rise gpr at the substation. The simulation results show the effects of the changes on the design and analysis of power. The substation design manual is not intended to replace asset management standards, but rather to act as a reference document that crossreferences existing standards and process documentation and plugs any gaps where asset management documentation does not exist. Part 3 c ode of practice for the design of industrial type stairs, permanent ladders and walkways.
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