CYMGRD software is a special program developed for grounding grid analysis and design to help optimize the design of new grounding grids as well as analyze and evaluate existing grounding grids for substations, power plants, industrial parks, industrial and civil plants. CYMGRD complies with grounding grid design standards such as IEEE 80 2013, IEEE 81 1983 and IEEE 837 2002. In addition, CYMGRD integrates a friendly user interface, optimized analysis algorithms, a diverse library system with soil resistivity, surface material layers, realistic models and powerful 2-D, 3-D graphics that allow users to switch between CYMGRD and AutoCAD, perform calculations and produce results quickly.
♦ Basic and advanced functions:
CYMGRD software provides a variety of functions, analysis modules, library systems, different grounding grid installation layout options suitable for actual conditions for comprehensive analysis and evaluation of the grounding system with the most accurate and reliable results. The main functions include:
– Finite element analysis of the ground grid conductors and rods
– Computation of the station ground resistance (Rg) and the Ground Potential Rise (GPR)
– Touch and surface potential analysis, inside and outside the grid perimeter, with color display in 2D or 3D representation
– Step voltage analysis
– Uniform or two-layer soil model from field measurements or user-defined values
– Computation of reduction factor (Cs)
– Library of the most common types of surface layer materials
– Library of typical station soil resistivity values
– Safety assessment calculations for maximum permissible touch and step voltages as per IEEE 80 2013
– Current Split Factor (SF) estimated from substation configuration data as per IEEE 80 2013
– Computation of the Decrement Factor (DF) from bus X/R ratio and shock duration data as per IEEE 80 2000
– DC component of asymmetrical fault current taken into account in the computations
– Electrode analysis for the optimal sizing of conductors and rods based on the most common type of electrode material as per IEEE 80 2013 and IEEE 837 2002
– Supports symmetrical or asymmetrical grids of any shape
– Arbitrarily located ground rods
– Ability to model return electrodes and distinct electrodes
– Ability to model concrete encased rods
– Grounding grid analysis using GEM chemicals
– Computation of maximum allowable single phase to ground fault current for a specified grid
– Import/export, ground grid construction and environment conversion between CYMGRD and AUTOCAD
♦ Applicable standards:
– IEEE 80-2013, IEEE 81-2012, IEEE 837-2002 Standards
– IEC 60474 Standards
– BS7354-1990 Standards
– EA-TS 41-24 1992 Standards
– CENELEC HD 637 S1 1999 Standards
– EN 50522 2012 Standards
♦ Attached documents:
– Cymgrd software: BR917034EN-CYMGRD – Substation Grounding Grid Design and Analysis