Mechanical Design And Stress Calculations For Overhead Lines
JOVE software is specialized in overhead transmission and distribution lines mechanical design. JOVE software allows the user, starting from data on line’s topography and on available material for building it, to choose the best possible places for all supports and to choose the necessary material (from conductors to foundations), checking for the respect of all conditions on clearances and on stress for conductors, insulator strings and supports (each bar of each tower may be tested in a few seconds), at any possible climatic condition for the line site. Then JOVE produces all necessary documents for control office and for site teams that will build the line. Already available in English, French, German, Italian, Spanish, Brazilian/Portuguese, Hungarian, Russian, Turkish, Arabic, Korean, Thai and Chinese, it will only take a week to have it translated in any other language, as soon as a customer will request it. A study done in any available language may then be printed in any other available language (as long as the necessary fonts will be available). Compared with more traditional design, JOVE software, that only cost the price of one tower, allows saving several towers on the very first line for which it is used!
The Accuracy of Results given by the Software depends on the Accuracy of Data Input. Therefore, Input is the object of all cares in JOVE :
- Pass-Word Protection allows Trainees to use the Software without any fear that they could disturb the Basic Data and Options (that would be impossible to detect afterward). The "Hyperfile" Organisation of this Data is such that it is impossible to get through this Protection with an Independent Editor or Spreadsheet.
- Consistency and Likelihood Controls are performed for each Input.
- Numerous help buttons are available, especially, every time a choice has to be made in a Data list.
This Basic Data is regarding the Conductor's Weight, Diameter, Elasticity, etc..., the Insulator Strings' Length, Breaking Load, the Towers' Hooking Points Position, Length Of Possible Feet Extensions, Allowable Stress, etc. (grouped in categories from Thin to Wider and from Weak to Stronger), and the Climatic Assumptions (grouped into Tables, so as to have all Extreme Conditions in Different Seasons at Line Site). For the users who want to compute Stress for each Bar inside the Tower and down to the Foundations, more details on Towers' Bars should be entered.
The other data allows the Software to adapt to any possible Local Regulation(for example, the Safety Factors and all Clearance Rules should be followed), Plotter Outputs(Characters' size, Line thickness, Title blocks etc.,), and Topographical Codes etc.
The data could be collected in many Ways. JOVE can read Data previously registered in a Spreadsheet, or on Theodolite's Diskettes (Leica, Sokkia, and Topcon Format are already implemented). It could be Raw GPS Measurement Results (Longitude, Latitude, and Altitude), allowing to have an output shown on Google Earth), or data from some Specialised Topographic Software File (EPS/Egypt, CREDO/Russia).The input data may be already projected on Line Axis for each point Cumulative Distance to Datum, Possible Deviation Angle, Information on Possible Obstacles and Forbidden Zones, for Supports, on Side Slopes, etc. The necessary Topographical Data for JOVE may also be read from an Aerial Survey File or entered directly into the Software. For using the proper Code for Obstacle and other information linked to Topography (Zone where supports are Forbidden, Allowed Ground Clearance, or for Soil's Quality, or Support's Installation Price due to Transportation Problems, etc...).
The Result is a Topographic Profile drawn on Screen where the user will be able to see the Ground Level (in Green, or In Red for Forbidden Areas), Obstacles, Side Slopes, Ground Clearance Limit (In Blue), Deviation Points (where it is compulsory to place a Support), marked by a Yellow Vertical Line. Schematic Map may also be displayed. Zoom is possible for Profile and Map.
For each New Study, the user is first guided in selection Of Necessary Material: Phase and Earth Wire Conductors, Insulator Strings, Towers. Then the Supports may be placed on Profile either one by one or by using one of the Two Automatic Spotting Facilities (Minimum and Maximum Span, Catenary Parameter or Initial Tension).
The Automatic Spotting Procedures are Very Powerful, as a very little time(few seconds) is usually enough(depending on the Computer's Processor) for placing up to 100 Supports for a Section. Defining the Size of Counter-Weights needed for limiting the Insulator String swinging on Suspension Towers. It is always possible for the Engineer to Improve and Correct the Support Spotting. Modification of Support Spotting is very easy, for example, Positioning Different Insulator Strings at Left and at Right of a Tension Tower), For Main Values (Position, Foot Extension, ...), etc.
For guiding the user in Choices and Modifications to be made, the Stress in Conductors, in Insulator Strings, and at Hooking Points inside the Towers Down to the Foundations may be Computed and Displayed for any Climatic Conditions. Installation Tension for each Span, Conductor's Clearance, Weight Spans, and Wind Spans are calculated. When displayed, these values are associated with the Resulting Security Coefficient. In case of any problem, a Red Warning (including a forefinger pointing toward the possible warning, in that case, would be displayed on the screen.
Whatever the language that has been used for Performing the Line Design, any one of the Thirteen Available Languages may be used For Editing JOVE's Results. All the output (results) available for display at the screen may be printed (for Tables) or plotted (for Drawings), Using any Printer or Plotter available. Texts may also be stored as Files, transferred to Microsoft Word (in RTF Format), or in Pdf Format. Tables can be saved in Microsoft Excel Format, and Drawings can be stored on Disk in DXF Format available for completion using Specialised Drawing Software as AUTOCAD (©Autodesk) or MICROSTATION (©Bentley).
The main difference between “Transmission” and “Distribution” line in JOVE Software:
Instead of Transmission Towers based on Foundation Blocks, on which Insulator Strings are directly Hooked, the Distribution Supports are Poles Driven in the Ground with their Top Independent Cross-Arms where Insulator Strings are Hooked.
The Transmission Module allows having up to 12 Bundles of 4 Phase Conductors with 2 Earth wires while the Distribution Module is limited to only 6 Phase Conductors and 1 Earth Wire.
The user with both Transmission and Distribution rights may also study/work on “Multiple Lines” that is from 2 to 4 different lines fixed on the same Poles with different Cross-arms (Totalling a maximum 12 Bundles Of 1 To 6 Conductors each for Phase + 2 Earth Wires).
The Structure Module dealing with Towers includes the Structure Sub-Module and the Distribution Modules includes the Low Voltage Network Sub-Module.
A Few References
Using 20 years of French experience with software Jupiter on sun workstations, JOVE has been created on pc in 1997. Since that it has kept being improved owing to its international experience, so as to be compatible with most national regulations around the world. The main customers for transmission lines are in France Sogreah and Tractebel, in new Caledonia Enercal (subsidiary of EDF) and abroad in Egypt rea (3 copies purchased through EDF), eps and shaker group, at Madagascar Jirama, in Korea Kepri, in Tunisia Cami, in Belgium Nexans (2 copies), in India reliance (2 copies), in Malaysia Toprank, in Algeria Kahrif (6 copies) and Al Elec, in Russia factor (4 copies) and in Cambodia Edc (2 copies).
Developed By G.C. Software
Distributors For India, CISTSOMAG, Nallakunta,