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. This connection is not ideal due to the resistivity of the soil within which the earth grid is buried. User guide secondary substation earthing design tool icp. This voltage gradient should not exceed the tolerable human body limit. The functions of grounding systems or earth mat in include.
Over the years grounding design terms and definitionsprocedures have been developed. The grounding system in substation is very important. Design of earthing grounding system in a substation grid. Pdf earth mat design for 233kv substation in rivers. Substation earthing is critical both to the operational performance of the power system, and the provision of a safe working environment. Highvoltage substations are fed by transmission lines with the earthing system solidly bonded to the substation earth grid.
Civil drawings substation plans and elevations, earth mat layout drawings etc. Fireproofing the substation ceiling and sealing the cable ducts against transformer oil leakage is vital in the event of a fire. Substation earthing system grounding system earthing mat. Under substation fault, both the substation earth grid and the pole grid. The cross section of the buried cable should calculated in accordance with the value of the phaseto earth short. Design and analysis of substation grounding grid with and. The earthing system, sometimes simply called earthing, is the total set of measures used to connect an electrically conductive part to earth. Earthing mat design for a power substation ms excel. Today we are going to discuss the design of substation earthing system. Technical specification 4124 issue 2016 guidelines. We have already given an introduction to substation earthing system in an article published earlier. It is well that the earthing systems are intended to protect equipment and personnel in and around the substation. International journal of engineering trends and technology.
The earthing system must be designed using latest version of the cdegs design software package. The function of substation earthing system is to provide a grounding mat below the earth surface in and around the substation which will have uniformly zero potential with respect to ground and lower earth. There are a variety of national and international standards available, which provide empirical formulae for the calculation of earthing design parameters and shock potential safety limits. Pdf guideline for earthing of buildings and industrial. Earth resistance design and evaluation of substation. The factors which influence the earth mat design are. Substation absd equipotential earth mat application guide. Substation and transmission lines earthing system design. Most affected parameters for design of earthing grids are. Any proposed design shall be approved by es networks at the design. In this design, these additional rods or mats are made to bond with the existing main ground mat.
Substation grounding tutorial ground matesh effect of safety regulations and safe working practices on earth mats copper lattice earthing earth mat design goa electricity department earthing mat design for substationearth mats copper lattice earthingearthing mat design for substationwhat does a good grounding of the power substation andsubstation earthing designearth mat design. Design safe buried earthing and grounding systems for applications including substations. International journal of engineering trends and technology ijett volume 15 number 8 sep 2014. Substation lightning protection and earthing standard documents should be brought to the immediate attention of tasnetworks for resolution and no action must be taken that might result in a breach of. Earth mat design substation earth system will have a combination of. Optimal design of substation grounding grid based on. Optimized design of earthing system for substations with.
Application guide for equipotential earth mat installation on substation structure mounted switches version. It is a salient area of design when either constructing a new substation or extending or modifying an existing substation. Substation grounding grid design therefore requires calculating of parameters related to earth. The substation earthing system comprises of a grid earth mat formed by a horizontal buried conductors. Earth mat design for 233kv substation in rivers state using etap. The substation earth grid is used as an electrical connection to earth at zero potential reference. Introduction earthing is essential wherever electricity is generated, transmitted and distributed or user, to ensure safety and proper operation of the electrical system. Ensure safety to personnel in substations against electrical shocks. The designer must use suitable cdegs earthing design module to model the grid and any third party infrastructure if it has been affected by development of the relevant substation. Earthing mat design for substation spreadsheet photo by input fields as per ansiieee std 801986 code.
Successful operation of entire power system depends to a considerable extent on efficient and satisfactory performance of substations. Substation lightning protection and earthing standard. Etap model for earth mat design etap model for earth. Advanced grounding s ground impedance and soil earthing mat design for substation earthing mat design for substation electrical power system grounding and ground resistance basics of substation design october 2016 earthing mat design for substationearth mats copper lattice earthingearthing mat design for substationwhat does a good grounding of the power substation andsubstation earthing. Important formulas for designing a substation grid earthing system. Hence substations in general can be considered as heart of overall power system. Earthing ofsurge arresters is through the earthing system. Build custom earthing systems, using finiteelements determine a safe design overview features videos screenshots faq testimonials training overview determine earthing system performance, touch and step voltage safety compliance. The substation grounding system comprises of a grid earth mat formed by a horizontal buried conductors. South african national standard miniature substations for rated a. Earth mat design can be done by manual calculations as well as with the help of computer software. Substation earth mat design the earth images revimage. Etap model for earth mat design etap model for earth mat. The earthing design tool will start and connect to the backend database as shown below.
Read about design of substation earthing system here. The legacy approach to secondary substation earthing design was based on one or two earth rods and combining hv and lv earths if the measured earth resistance was less than 1 ohm. Earth mat design for hv and ehv substation electrical. Though manual calculation is a good, software tools ensure a detailed design so that the earth mat is neither underdesigned hence safe nor this paper presents the complete design of earth mat. Earth mat designing of substation free download as powerpoint presentation.
Earth mats manufactured from high conductivity copper tape also reduce the danger of exposure to high step and touch voltages to substation and authorised personnel working on high voltage switching providing reliable earthing in high fault current and step potential avoidance applications, such as high voltage substations. Scribd is the worlds largest social reading and publishing site. Guideline for earthing of buildings and indust rial plants 1. Earth mat design substation earth system will have a combination of buried horizontal conductors in rows and columns and vertical electrodes. A sold metallic plate or a system of closely spaced bare conductors that are connected to and often placed in shallow depths. Earthing system thus design must be easily maintained and future expansion must be taken into account while designing the dimensions of earth mat. The ergon energy design philosophy is to provide substations.
A lot of studies were made to describe and analyze the substation grounding grid design criteria. Earth current considerations for earth mat design in hv substations by the late alan ware. This paper is concerned with earthing practices and design for outdoor ac substation for power frequency in the range of 50 hz. Safegrid earthing electrotechnik pty ltdelectrical. 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 earth grid for a 3311kv gis substation at a. Fault levels for all voltages at substation or site these are used. Before 1960s the design criterion of substation earthing system was low earth resistance.
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