The main issues related to ground grid design and determination of optimum method for substation mesh design is presented in this. Expert instructors with decades of substation design experience will guide you in learning how to develop reliable substation. Sep, 2017 an introduction to grounding calculations and why they are necessary. Safety design of ground grid in distribution substation gmsarn. Distribution substation a distribution substation transfers power from the transmission system to the distribution system of an area.
The designer must use suitable cdegs earthing design module to model the grid and any third party. Ieee std 8020 guide for safety in ac substation grounding ieee std 812012 guide for measuring earth resistivity, ground impedance, and earth surface potentials of a ground system ieee std 3672012 recommended practice for determining the electric power substation ground potential rise and induced voltage from a power fault. Optimal design of substation grounding grid based on genetic. It describes the detailed computer model of the east central substation grounding grid and shows how to use the malt. Welldesigned grounding system is very much essential as far as the safety of the crew and the substation equipments are concerned. Index terms electrical substation, engineering design, grounding systems, grid resistance, ground potential rise, mesh voltage, step potential, touch potential i. The comparison between theoretical values and experimental values for various types of grounding grid performance at fixed depth is carried out 5,6. Power substation design calculations a checklist of 18 studies for engineers to consider. 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. Pdf the grounding grid provides a common ground for the electrical equipment as well all the metallic structures in the substation.
This paper will present ground potential rise gpr causes, effects, variations in the values gpr in high voltage substations. National grid substations technical specification ngts 2. Pdf the design of 110kv substation grounding grid with high. The proper grounding of a substation is essential and very important for the following. First, it provides a means of dissipating electric current into the earth without exceeding the operating limits of the equipment. Pdf simplified method for substation grounding system design. The design of grounding system for gis indoor substations and ais is quite different. In high and medium voltage air insulated substations ais the electromagnetic field, which causes are the static charges of bare cable and.
Substation grounding a project presented to the faculty. Optimal design of grounding system for a substation is complex due to the involvement of numerous parameters. The main difference is that the ground grid of gis is attached to the steel. Step and touch voltage are used to derive the safety criteria for grounding grid design. 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. By accessing various other input pages like grid layout, soil model and system data, further details about. Design of grounding grid according to ieee standards. The ground grid consists of horizontal interconnected bare conductors mat and ground rods. The substation should surround the perimeter and take up as much area as possible to avoid high current concentrations. Substation earthing system design underground horizontal earth mesh matgrid the mesh is formed by placing mild steel bars placed in x and y directions in mesh formation in the soil at a. 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. Substation engineering power grid engineering, llc. Bs 7354 code of practice for design of highvoltage openterminal substations. The following points serve as guidelines to start a grounding grid.
Hence substations in general can be considered as heart of overall power system. Design and analysis of ground grid system for substation using etap software and fdm code in matlab deep b. The substation grounding grid is a system of horizontal, interconnected bare ground conductors, spaced a few meters apart, buried in the earth at a depth varying from 0. Electrical 20142018 sardar vallabhbhai institute of technology, vasad vadodara, india abstractthe paper depicts about design of ground grid system for 6611kv rectangular substation. Index terms electrical substation, engineering design, grounding systems, grid resistance, ground potential rise, mesh voltage, step potential, touch potential. Effective grounding system design is important as it deals with. This page allows access to all other input output modules. Optimized design of substation grounding system using newly. Successful operation of entire power system depends to a considerable extent on efficient and satisfactory performance of substations. Also, the expected step voltage is less than the acceptable step voltage limit.
Design and analysis of ground grid system for substation. The following points serve as guidelines to start a grounding grid design. The following data given in the table is considered for the substation ground grid design table 1. Substation ground grid touch and step calculations the ground grid is expected to produce a maximum mesh potential rise in the center of each of the corner meshes, which is less than. An air insulated substation is chosen for the analysis located in pakistan. For economy of construction the collector system operates around 35 kv, and the collector substation steps up voltage to a transmission voltage for the grid. Pdf design analysis and optimization of ground grid mesh. An introduction to grounding calculations and why they are. This fundamental course leads you through a stepbystep study of the substation design and construction process. In a properly designed system, this gradient should not exceed the limits that can be tolerated. Provide a safe and costeffective conceptual grounding system design for the substation by means of accurate calculations properly accounting for a realistic approximation of the soil structure typically a multilayered soil structure, attenuation along ground conductors i. Substation earthing system design underground horizontal earth mesh matgrid the mesh is formed by placing mild steel bars placed in x and y directions in mesh formation in the soil at a depth of about 0. Joe is a principal engineer in the substation engineering department at xcel energy and has held many roles in the department since 1998. Pdf design analysis and optimization of ground grid mesh of.
The main issues related to ground grid design and determination of optimum method for substation mesh design is presented in this paper. Design analysis and optimization of ground grid mesh of extra high voltage substation using an intelligent software conference paper pdf available november 2014 with 1,514 reads how. Overview on etap capabilities in ground grid system design and analysis using ieee 80 standard and finite element method fem. The uniform and two layer soil structure for substation ground grid design is mostly used in india 4,5. Aspects of soil resistivity measurements, area of the ground grid, calculation of tolerable limits of. The ergon energy design philosophy is to provide substations. Substation earthing and bonding and their integration into a substation and the. Perform other studies such as bus calculations and ground grid study. The design of the ground grid to control voltage levels to safe. The substation grounding system is an essential part of the every electrical system. The purpose of this paper is provide knowledge about the gpr, substation grounding grid and step and touch potentials. Chapter 4 presents the initial design of the grounding system.
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. Design of grounding system for an electrical substation. Since then, many additional constructions and installations have been performed on the site, and in some cases, it is unclear if the grounding grid has been properly considered in these activities. The substation earthing system comprises of a grid earth mat formed by a horizontal buried conductors. The functions of grounding systems or earth mat in include.
A substation standards switch operating platforms steel design and. Welldesigned grounding system is very much essential as far as the safety of the crew and the. Optimal substation ground grid design based on genetic. Read about design of substation earthing system here. An introduction to grounding calculations and why they are necessary. Substation grounding design challenges and lessons learned. Ieee guide for safety in ac substation grounding ieee std 802000. The objective of this paper is to design ground grid mesh of a 233kv substation with expected maximum short. The protective scheme installed in any substation should be fully active to ensure its proper and accurate operation in. Design analysis and optimization of ground grid mesh of extra high voltage substation using an intelligent software conference paper pdf available november 2014 with 1,514 reads how we.
Pge is committed to high quality services using a combination of internal and strategic external resources, and is ideally suited to the engineering, construction and design of power substations. The protective scheme installed in any substation should be fully active to ensure its proper and accurate operation in case of any fault. Cost effective grounding grid design for substation soni m, dr. The comparison between theoretical values and experimental values for various types of. Distribution substations michigan technological university. The following sitedependent parameters have been found to have substantial impact on the grid design. The purpose of a ground mat study is to provide for the safety and wellbeing of anyone that can be exposed to the. The collector substation can also provide power factor correction if it is needed, metering and control of the wind farm. Optimal design of substation grounding grid based on. Substation earthing system grounding system earthing mat. Calculationofimportantdesignparametersforgroundingsystemsi.
To ground the fence of the grounding region separately 6. In addition to substation projects, joe is active in standards work both at xcel energy and in ieee substations committee. Provide the ground connection for connecting the neutrals. Electrical 20142018 sardar vallabhbhai institute of.
Introduction to substation earthing grid in high and medium voltage 1 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 the ground. Ground potential rise gpr is a concern in the design of substation grounding grid. Ieee guide for safety in ac substation grounding ieee std. Pge is a proven leader of fullservice substation construction and engineering concept design, economic evaluations, physical design, civilstructural engineering, ground grid design and. Optimized design of substation grounding system using. All rus borrowers rus electric staff effective date. Design of earthing grounding system in a substation grid. 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.
Etap model for earth mat design etap model for earth. The grounding system in substation is very important. Since then, many additional constructions and installations have been performed on the site, and in some. Power substation design calculations a checklist of 18.
In a properly designed system, this gradient should not exceed the limits that can be tolerated by the human body. Ground grid mesh used under substation ground consist of horizontal conductors connected with vertical rods. This paper presents methods for optimization of substation ground grid. Pge is a proven leader of fullservice substation construction and engineering concept design, economic evaluations, physical design, civilstructural engineering, ground grid design and equipment specifications. The fence is connected to a separate grounding conductor. Calculations of and development grounding grid system in the substation area where the top soillayer ijtsrd, issn. A substation standards switch operating platforms steel design and details 49. The substation ground grid design is based on the substation layout plan. This paper will present ground potential rise gpr causes, effects, variations in the values. Ensure safety to personnel in substations against electrical shocks. Pdf design and analysis of substation grounding grid. The proper grounding of a substation is essential and very important for the following two reasons. Ieee std 8020 guide for safety in ac substation grounding ieee std 812012 guide for measuring earth resistivity, ground impedance, and earth surface potentials of a ground. E substation standards switch operating platforms steel design and details 48.
The grounding grid was installed upon the construction of the nuclear power plants. Pge is committed to high quality services using a combination of internal and strategic external resources. Pdf this paper presents the design of 110kv substation grounding grid with high resistivity soil. Substation grounding a project presented to the faculty of. The input for a distribution substation is typically at least. It describes the detailed computer model of the east central substation grounding grid and shows how to use the malt computation module to determine the grounding grid impedance that will be used in the computation of the fault current distribution in chapter 5 step 2. Calculationofimportantdesignparametersforgroundingsystemsinsu. Substation ground grid touch and step calculations the ground grid is expected to produce a maximum mesh potential rise in the center of each of the corner meshes, which is less than the acceptable touch voltage limit. This bulletin is an update and revision of previous rea bulletin 651, design guide for rural substations revised june 1978.
Provide a safe and costeffective conceptual grounding system design for the substation by means of. Design and analysis of substation grounding grid with and. The function of mesh is to dissipate extremely high current generated in any. The grounding grid provides a common ground for the electrical equipment as well all the metallic structures in the substation. Cost effective grounding grid design for substation. Pdf design and analysis of substation grounding grid with and.