ANALYSIS OF METHODS DETERMINATION GROUND RESISTANCE OF HUMAN FEET

Abstract

To reduce the touch voltage at power plants and substations use the laying of a surface layer with a resistivity greater than the original soil. Determining the ground resistance of human foot (resistance of the surface of such a layer) is an important characteristic that must be taken into account both when designing a grounding device and during operation. Despite the practical measurement of the specified value by the specialists of Institute “Molniya” of the NTU “KhPI”, the issue of determining the resistance of the base is not covered in scientific and scientific-practical publications of Ukraine. Therefore, one of the goals of the authors is to draw attention and raise a dispute regarding the methods for determining this parameter. The first step towards this was the review and analysis of existing methods of determination. The experimental and computational methods for determining the ground resistance of human feet and recommendations for their use are were analyzed. The analysis of all known methods for determining the resistance of base made it possible to group ones into groups of calculation and experimental methods (the total number of analyzed methods is 21). Based on the results of the analysis of a number of literature sources and practical experience of monitoring the condition of grounding system, the advantages and disadvantages of each method are determined. Recommendations for their use depending on the condition of the object (current or designed), weather conditions, the presence of additional local inclusions or service areas. The practical significance of the work is the ability to optimally choose the method of determining the resistance of the surface during the control of the state of the grounding device The analysis determines the limits of the use of specific engineering techniques and is useful for designers and highly qualified specialists who perform work on diagnosing grounding devices of existing power facilities.