Grounding can be done any time, any place, anywhere and no one has to know. A safe grounding design thus serves two main objectives open electrical, 2017. Two day national conference rteece2014 17th,18th january 2014 88 optimized design of substation grounding system. Improving the reliability of power systems with more accurate. The cross section of the buried cable should calculated in accordance with the value of the phasetoearth short. Pdf three dimensional grounding grid design researchgate. Difference between grounding and earthing one of the major difference between the grounding and the earthing is that in grounding, the current carrying part is connected to the ground whereas in earthing the noncurrent carrying parts is connected to ground. Most utility systems which supply service for commercial and industrial systems are solidly grounded. Apr 09, 20 high voltage electronic system area is to bereferred as substation. The practice came in to existence in the early days of electricity when the.
Design of earthing system for 400 kv ac substation a case study. This course is intended to prepare the target persons with the ability to perform all electrical grounding system design for domestic, commercial and industrial facilities and ac substations. No attempt is made to cover the grounding problems peculiar to dc substations. This design standard has the purpose of creating a consistent application for the grounding and bonding of electrical systems throughout the east side union high school district. Importance of grounding techniques 0 5 10 15 20 25 30 35 40 45 percent used grounding 42% case shield 22% cable shielding 18% filtering 12% pcb layout 6% grounding 42% case 22% cable 18%. Connections used in substation grounding, new york. Abstract substation grounding is a critical part of the overall electric power system.
This example shows the method for designing a grounding grid following the standard ieee 80 safety criteria. These factors make the design of an earthing system. Ieee industry applications society atlanta chapter january 19, 2010 meeting 2 purpose of grounding lightning and surge protection stabilize circuit potential and assist in proper operation of. Design standard grounding and bonding for electrical systems. The earth must be treated as a semiconductor, while the grounding electrode itself is a pure conductor.
Grounding impedance measurements in maintenance and inspection. Third, soil resis tivity directly affects the design of a grounding system, and it is to that task that this discussion is directed. Article 250 is organized into 10 different parts that deal with specific requirements with regards to bonding and grounding. 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. After modeling the area, we will engineer an electrical grounding system design that will meet your performance objectives. You can also think of it as distraction, centering, a safe place, looking. Statistically, 9095% of all system shortcircuits are ground faults so this is an important topic. A quantitative analysis of the effects of lightning surges is also beyond the scope of this guide. 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. Optimized design of substation grounding system using.
Wellman, optimal ground grid design for large ehv substations with autotransformer, publication no. The impacts of failure to adhere to proven and acceptable grounding practices for the design and. Engineers want to design systems that protect human and equipment while providing an optimized economic solution without over designing grounding systems. Grounding design calculations part seventeen electrical. Distraction works by focusing outward on the external worldrather than inward toward the self. This practice is suitable when that ground point has a high frequency low impedance path to the equipment creating the condition. Electrical grounding practices for aerospace hardware reflected in the standard procedures and techniques resulted in reliable circuits that presented minimum hazard to personnel and equipment. This is a discussion of the basic principles behind grounding systems and how grounding is related to safety and the effective operation of circuit protection devices such as fuses and circuit breakers. Grounding and bonding for electrical systems version 1. The design of a grounding grid in a substation is formulated as a. Design and analysis of substation grounding grid with and. The engineers at comsite construction company can help you plan and execute an electrical grounding design that will provide the best performance available within the constraints of your available area, budget, and.
Earthing or grounding is a technique which is as old as the use of electrical power on a commercial scale. Grounding system design calculations 1 course description. Pdf the main purpose of this work is the development of an optimization model for the design of the grounding grid in electrical substations. Substations involves many earthlings through individual electrodes, which will have fairly high resistance. Principles of electrical grounding john pfeiffer, p. Substation grounding design challenges and lessons learned. Over the years grounding design terms and definitionsprocedures have been developed as well as appropriate standards, most notable. 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. Cost effective grounding grid design for substation. Industrial power system grounding design handbook by j. It depends on the frequency and can be determined using a.
Substation grounding system design studies are increasing as available fault currents increase on todays electrical power grid. High voltage electronic system area is to bereferred as substation. In this case study a normal earthing design is done using etap. Shields is a comprehensive study guide for the design of industrial and commercial electrical power systems as dictated by neutral grounding and groundfault protection practices. Over the years grounding design terms and definitionsprocedures. There are two primary functions of a safe earthing system. Ieee guide for safety in ac substation grounding ieee std. Technique for grounding system design in distribution. A key parameter in the design of lightning protection systems for critical or. The problems of system grounding, that is, connection to ground of. Importance of grounding techniques 0 5 10 15 20 25 30 35 40 45 percent used. The values of these parameters have to be kept within certain established emits, keeping.
Importance and need of accurate modelling of soil of high. Hence substations in general can be considered as heart of overall power system. Earth rod dimensions depending on the design specification of the earthing system and the corresponding earthing wells, various earth rods of different dimensions would be incorporated. It shows the procedure for designing the grounding grid of a substation with voltage levels of 115 kv and 34. Ground design objectives for emc minimize cross talk.
Isbn 073815640x ss95700 no part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Optimal design of grounding system for a substation is complex due to the involvement of numerous parameters. Effective length is the length above which, no considerable reduction of the high frequency impedance of the electrode is observed. All this data is fed to the etap and the grid design is done as shown in figure. An important aspect of substation grounding system design is the calculation of the ground resistance offered by the grounding grid, and the values of the mesh and step voltages on the surface. Pdf substation grounding grid design using alternative. Review of substation grounding practices, safety and. The design team andor contractor are held responsible to be familiar with the. The disaster will happen when a fault occurs in the substation. Background solectria prepared this document to aid the pv developers with the design of grounding bank in order to be.
A new evolutionary method for designing grounding grids by. Cost effective grounding grid design for substation soni m, dr. Electrical earthing grounding introduction electrical earthing grounding is one of the most important aspects of any electrical installation. Ground system design col john keesee 6172004 1 lesson objectives the student will. Grounding system design and measurements for critical installations mitchell guthrie, independent engineering consultant, 234 guthrie road, blanch, nc 27212 usa, 336 694 6177, 336 694 5224.
Design guide for rural substations usda rural development. Atttp76416001 grounding and bonding for network facilities design. On the other hand, if design without a knowledge of significant factor for grounding system. Grounding, therefore, is a very practical issue that should be. Design of grounding system for an electrical substation. Comply with nfpa 70, article 250, for types, sizes, and quantities of equipment grounding. Design of earthing grounding system in a substation grid. Know capabilities of typical dedicated ground systems and common multiuser. For effectivelygrounded systems this ratio is usually at least 60% 2. The problems of system grounding, that is, connection to ground of neutral, of the corner of the delta, or of the midtap of one phase, are covered.
Substation grounding grid design and analysis module is specially designed to help. This bulletin is an update and revision of previous rea bulletin 651, design guide for rural substations revised june 1978. A grounding bank design guideline to meet the effective grounding requirements per ieee p1547. Mortezaeei 2 1 electrical engineering department, seraj higher education institute, tabriz, iran, n.
Ieee std 1422007 revision of ieee std 1421991 ieee. As you can see in figure 1, this design is to prevent the secondary side from being damaged by the high voltage on the primary side, as the current will be conducted to the ground through the grounding wire to protect human lives. However, if detailed design information is not available this manual can also be used to install an appropriate earthing system. Successful operation of entire power system depends to a considerable extent on efficient and satisfactory performance of substations. Rahi1, 2abhas kumar singh, shashi kant gupta3, shilpa goyal4 electrical engineering department, national institute of technology, hamirpur, india1,2,3,4 abstract this paper presents the design of earthing system for 2 kv substations and simulation for. This bulletin provides a basic design guide and a reference tool for designing rural.
The economics is an important factor as well as human safety. The main purpose of this paper is the development of an optimization model to design grounding grids in electrical substations. Shields is a comprehensive study guide for the design of industrial and commercial electrical power systems as dictated by neutralgrounding and groundfault protection practices. Technique for grounding system design in distribution substation. Firstly, ensure that a person who is in the vicinity of earthed facilities during a fault is not exposed to the possibility of a fatal electrical shock. Transformer primary high voltage secondary low voltage grounding wire earth ground. Electrical earthing grounding is one of the most important aspects of any electrical installation.
Calculationofimportantdesignparametersforgroundingsystemsinsu. Grounding is a set of simple strategies to detach from emotional pain for example, drug cravings, selfharm impulses, anger, sadness. Effective design of large grounding systems usually involves calculation of the effective length of horizontal grounding electrodes. Pdf grounding system design in electrical substation. Design and analysis of substation grounding grid with and without considering seasonal factors using edsa software mithun mondal, dr r. The main objective of this paper is guide the first step for someone who attends to design of grounding system before study in details later. Mindfulness is a mental state achieved by focusing ones awareness on the present moment, while calmly acknowledging and accepting ones feelings, thoughts, and bodily sensations. As per the standard steps of earthing system design the values of fault current, conductor size, grounding resistance is to be found out using the associated formulas as per ieee80. Important formulas for designing a substation grid earthing system.
Design of earthing system for 400 kv ac substation a case. A grounding bank design guideline to meet the effective. The overview of grounding system can protect damage from fault such as can save a human life and power system equipment. Calculationofimportantdesignparametersforgroundingsystemsi.
Design of earthing system for 400 kv ac substation. The range of diameter for the earth rods vary from mm to 25mm mm, 16mm, 20mm, 25mm 3. Pdf this study presents an advanced methodology and a computer model for analysis of. Be able to list the functions performed by a space systems ground support system. The normal grounding practice is to connect the rfi filters to same ground point used by the equipment causing the condition. Review of substation grounding practices, safety and constructability enhancements. Welldesigned grounding system is very much essential as far as the safety of the crew and the substation equipments are concerned. Grounding of urban gis substation connected to ommercial. Student 2,3assistant professor 1,2,3 department of electrical engineering 1, 2, 3 g.
Optimized design of substation grounding system using newly developed ieee compliant software issn. 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. Difference between grounding and earthing with comparison. All intellectual property rights including without limitation any, patents, logos, designs, circuit layouts, trademarks, moral rights and know how in the.
Industrial power system grounding design handbook john. The size and type of the substation can be vary, but those design aspects are similar. Grounding puts healthy distance between you and these negative feelings. I general ii system grounding iii grounding electrode system and grounding electrode conductor iv enclosure, raceway, and service cable grounding v bonding. An urban gis substation grounding system design is a complicated task in order to provide an adequate system that meets specific criteria with regards to personnel safety and integrity of equipment during a fault condition.
Considerations for instrument grounding application note kuo yenlung. The other differences between them are explained below in the form of the comparison chart. Ieee std 4872007, recommended practice for the protection of wireline communication facilities serving electric supply locations. Designing for a low resistance earth interface grounding. The design team andor contractor are held responsible to be familiar with the provisions contained herein and with other sections of this specification as applicable to the completion of the installation. Optimized design of substation grounding system using newly. These rfi filters, like other electrical equipment, require grounding. Ansiieee std 802000, ieee guide for safety in ac substation grounding.
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