The design requirements of electrical substations of high and extra high voltage have radically changed in recent years. The design times have gone from years to months, and the demands are increasing.This creates a new challenge for engineering firms: it is necessary to make designs in the shortest possible time, while maintaining its quality and requires an effort in aligning work teams. In addition to the technical challenges, other asspects, play an important factor; for example the difficulties of finding land with the appropriate conditions (dimension, soil conditions, topography, acces, etc) for the substation, that demands to the engineers studied several alternatives within the same deadlines assigned, whereas acquisition of lots and environmental restrictions.Likewise, during the process of basic and detailed design of a substation, it is indispensable to make adjustments due to factors external to the design team (changes of the lot, change of equipment, stakeholders change orderss, adjustment of incomings of power lines, etc.); or internal factors such as lack of, sufficient and experienced qualified personnel, or high rotation of this personnel, failure of unified management of the information (parameters and criteria of designs, specifications and requirements of customers, versioning of drawings and documents, etc.).This has created great pressure on the engineering firms, expected to efficiently address ongoing requirements of changes in the scope requested by various stakeholders in the project, without affecting delivery times, costs of the work and quality of the designs.During the past 10 years, HMV engineers Ltda., has developed two complementary tools in design assisted by computer (HMVTools and DISAC) which allow optimizing the time and reduce risk in the design of high and extra high voltage substations. These tools integrate an environment of applications oriented to make the electrical, mechanical and civil calculations(including the memories required to sustain the results), complemented with a CAD design platform that allows to generate the three-dimensional model of the substation, associated with the results of the calculation reports obtained during the design process.These tools are supported by the knowledge and experience acquired during 50 years in the practice of consulting, management and design of electrical projects of high and extra high voltage transmission systems, and taking advantage of advances in information systems and technologies BIM (Building Information Model).The working method generated by the use of these tools guarantee a correct workflow between different disciplines that interact in the project, reducing considerably the time of design and minimizing the risk of errors during the design stage which can affect the construction process of the substation. In this way it avoids greater durations and cost overruns for the projects. Figura 2. Model integrated disciplines2. HMV ToolsHMV Tools is a software tool developed under a WEB environment, allowing a design team distributed geographically to work on the same model, achieving benefits such as:• Unification of design procedures: standardized calculations based on international standards and the compilation of good practices of engineering that HMV has developed.• Avoid the calculations in work sheets or personal programs routings and formulas: This allows to reduce errors due to engineering knowledge problems, inadequate use of formulation ”copy and paste” problems; working with outdated file, loss of the calculation by accidental deletion of the file on the user's computer between others.• Unification of information design: the design input parameters, as well as the output results , will be available in only one place and not distributed on various computers, files, or posts.• Reduce design time: engineers are more dedicated to the concept of engineering and analysis of results instead of reports and formulas to present to the client..• Reprocesses time reduction: A change can be identified in time, so the adjustment to the design will take less time.The programs are based on the requirements of international standards (IEC, IEEE) and unifies an installation input data to have a single source of information and the form of presentation of the results, establishing a template standard for the presentation of the calculation reports.HMV Tools creates an automatic workflow, with facilities that allow registration of the stages of revision, the versions, approvals, and quality control of designs, ensuring reliable results because of the use of controlled procedures and data.HMVTools has the following calculations, grouped by modules of disciplines:Input general data: Project Manager provides the design parameters for all the variables that have impact on the design, such as height above sea level, short circuit levels, temperature and wind conditioners (averages and maximums), seismic intensity, voltages and current ratings, etc. This information is used by all designers and can only be edited by the Project Director, ensuring a unique source of information. Figure 3. integrated process modelElectromechanical module: This module includes the calculations required by the electrical engineering as:• Selection of the surge arrester• Coordination of insulation (IEC 60071)• Conductor verification (Flexible or rigid) o Operating temperature of the conductor (IEEE 738, CICRE 207)o Cable section for current of short circuit(IEEE 605)o Corona effect (IEEE 605) • Calculation of mechanical stress, tensions and sag of strain bus (finite elements)• Calculation of effort in pipes (rigid busbar) and calculation of efforts in insulators.• Calculation of short circuit efforts for strain bus (IEC 60865)• Calculation of shielding (IEEE Std 998).• Estimation of soil resistivity (model 2 layers using genetic algorithms).• Calculation grounding (by method of images). Figure 4. HVMTools, Calculatios for level voltaje. Figure 5. HMVTols,. Segurity configuration.Structures module: this module enables structural engineers to calculate the loads transmitted to Foundation-level by structures and equipment, as well as loads for the calculation of foundations and anchoring bolts. This calculations are made interacting with other applications of the same HMV Tools. The module consists basically of four subroutines:• Loads on equipment calculations (weight, wind, earthquake, short circuit).• Loads on the structure support calculations(weight, wind, earthquake).• Combination of loads in accordance with the regulations of different countries.• Anchor bolt calculation.Civil module: This module allows civil engineer to determine the dimensions of the foundations (spread footing type), and estimate foundation steel reinforcement. Figure 6. Short Circuit Analysis - IEC 60865 with HMVTools 3. DISACDisac is a design tool for the physical layout of substations, it use AutoCAD as drawing platform, and it is applicable to air-insulate substation of high and extra high voltage.DISAC optimizes designs of substations with great quality and reduced times, through the use of the graphic environment of AutoCAD. It generates isometric drawings, plants, sections and details in 3D.The engineer does not require advanced knowledge of AutoCAD to get the model of the substation in 3D, list of materials, check interferences or clearances.The program allows model the external part of the switchyard such as dead-end structures, equipment, insulators, cables, tubes or elements or volumes of buildings. It also allows model the buried part of the switchyard as the foundations of gantries and equipment, cables ducts, and the grounding grid..All these components are saved in the database of the drawing, allowing several people work on different modules. These modules areElectromechanical module: this module includes different external elements of the switchyard.• Dead-end structures: these are configurable in the program, can be modeled as lattice or solid structures.• Equipment: Disac has a library of equipment for each voltage level, it is configurable by the user and is continuously growing. The Equipment is modeled as scaled blocks in AutoCAD, dimension and shape are very important.• Connections with flexible conductor: the library of flexible conductor has information of different cables as type, size, diameter, weight, among others, which are important to properly model the connection shape, checking clearances and calculate lengths of cables.• Module of rigid connections: this module allows drawing connections with tubes, include diameter and thickness of each type of connection.• Module of Strain Bus: this module allows drawing strain bus taking into account the cable properties, the string insulators, and other loads as the connections to equipment and concentrated loads, The module uses finite differences calculation procedures to obtain the cable deformations .. Figure 7. Disac - Structures, equipment, flexible and rigid conductorsModule of Shielding: this module includes the protection elements as shielding masts and shielding wires in order to model the lightning protection surfaces. These surfaces are calculated based on the rolling sphere method and the calculation of protection radius which are imported from the HMVTools program and calculated with the shielding module based on IEEE-998. It is also possible calculate the protection radius based on recommendations of NFPA-780, IEC 62305 and NTC 4552 for buildings or other structures in switchyard. Figure 8. Protect shielding lighting zone by DISACModule of grounding grid: this module is made up of cable routes, earthing rods and connections. The distribution routes, grounding cables and earthing rods are imported from the HMVTools program, where were calculated previously. Disac allows adjust these cable routes and earthing rods distribution, to export again to HMVTools program for a new calculation. These adjustments are necessary to prevent interferences with other modules as foundations module, trenches, or drainages. Disac also imports the touch voltage surfaces calculated in HMVTools by superimposing these on the switchyard model, to allow validating the security inside the substation and allowing to optimize the design of the mesh.Module of civil foundations: this module includes foundations in 3D for each column or equipment of the electro-mechanical module, each foundation is imported from the HMVTools program where were previously calculated. This allows generating in a reliable way the drawings of civil foundations of the switchyard. It also imports bar charts and dimensions charts for each foundation calculated in the HMVTools program.Module of cable trenches and cable ducts: this module includes the cable ducts, the trenches and the pulling boxes, in AutoCad in 3D. .Module of drainage: this module includes the pipes distribution and the man holes locations used in the drainage system of the substation. This model takes into account the inclination of the land and the slopes of each pipe of the drainage system.All these modules feed from master model , each one can be worked simultaneously by different engineers and in this way coordinate to identify interference between the different modules Figuere 9. Cable trench, drainage pipe, foundation and earth mesh Figuere 10. Estructure, equipment, foundation and earth meshModule of Materials list: this module generates detailed or summarized lists, of all components of the substation.Module for export and import to HMVTools : this module converts a substation designed in DISAC, to a digital model that is stored in a database, and then allows to import the partial or total model according to the requirements of the designers from different workstations. This facilitates that several engineers from different disciplines and specialties work on the same digital model, reducing the errors due to changes in the physical layout for the reason that they work on a single master model. Also reduces response times by updates in the design, for example: a change of an equipment location affects the drawings of civil foundations and possibly the drawings of grounding grid. With this module is not required that sections be ready, to perform the respective update.Communication of changes: in the HMVTools program, the designers and stakeholders are registered to mailing lists notification of changes that occur in the calculations or model; so, when changes are made, mail is sent to interested parties. For example a change in the dimensions of an equipment foundation are notified by mail to designers of the grounding grid, trenches and cable ducts, to verify that change does not interfere with these systems.CONCLUSIONThe BIM tools combined with centralized procedures of standardized designs and data bases, have allowed HMV engineers improve their response capacity in the design of high and extra high voltage substations, optimizing design times, reducing cost, increasing quality and facilitating the learning curve to the new designers.BIBLIOGRAPHY[1] Working Group B3-15 CIGRE. “Guidelines to cost reduction air insulted substation” August 2008.