Grounding Electrode Resistance Research Articles

Tower impulse grounding resistance measurement based on multiple frequency impedance

AbstractTower impulse grounding resistance is important for judging the lightning protection performance of transmission lines. Therefore, it is significant to accurately measure the tower impulse grounding resistance. Existing measurement methods mainly contain the real‐type test method and the impulse coefficient method. However, the real‐type test method requires heavy and complex excitation and measuring equipment, which is difficult to be used in a practical environment. The impulse coefficient method adopts the empirical equations, which could have large measurement errors in different environments. To solve the above problems, this paper studies a novel impulse grounding resistance measurement method (IGRMM) based on multiple frequency impedance. Spectrum characteristics of typical lightning currents and the calculation method of impulse grounding resistance of grounding electrodes are studied, the IGRMM is proposed. Finally, a case study and on‐site tests are carried out. The results show that the proposed IGRMM can accurately obtain the impulse grounding resistance by measuring grounding impedance at a few frequency points, which helps accurate and convenient evaluation of impulse grounding performance in practical environments and lightning protection performance of the power transmission systems.

ANALISIS PENGARUH PENAMBAHAN ELEKTRODA TERHADAP NILAI TAHANAN PENTANAHAN TOWER 105 SUTT 150KV MANINJAU - PADANG LUAR

In the process of distributing electrical energy, the transmission system plays an important role, for the conductor of the 150 kV High Voltage Air Line (SUTT) that connects the GI. Review with GI. The Padang Luar grounding system plays a very important role in reducing the impact of disturbances caused by lightning. For this reason, security is needed that can secure this SUTT from various disturbances that occur along its path. The value of the stability of this grounding system must be maintained in accordance with predetermined standards in order to maintain the quality of the distribution, especially when there is potential for interference from the transmission line.The standard for the grounding value that must be used is that it must be below 10 . Evaluation of the value of grounding resistance in the conductor is carried out to maintain, maintain and or improve the quality of the grounding because the value of grounding resistance can change from time to time due to the influence of the resistance value of the soil type and the grounding system itself.Tower 105 which has a grounding resistance value above 10 , it is necessary to reduce the ground resistance value, based on the calculations carried out, more effective results are obtained by using a grounding system of two electrode rods planted perpendicular to the ground for S > L, using an electrode with a diameter of 1 “(25.40 mm) can reduce the value of grounding resistance at the foot of the tower (stub. A) by 37.72% from 12.46 W to 7.76 W; tower foot (stub. B) by 37.71 % from 12.65 W to 7.88 W; tower foot (stub. C) by 37.70% from 13.37 W to 8.33 W; and the tower legs (stub. D) amounted to 37.74% from 14.31 W becomes 8.91 W. Keywords: transmission, soil resistivity, electrode grounding resistance

Influence of Nonlinear Processes in Soils on the Impulse Resistance of Grounding Electrodes

The article presents the results of laboratory studies of nonlinear processes during the flow of pulsed currents into moistened soil from electrodes modelling grounding devices of electric power facilities. A methodology for studying the pulse parameters of grounding devices has been developed and a laboratory stand and a generator measuring system have been developed on which these investigation were performed. The experiments were carried out on three types of electrodes at voltages of 20 - 50 kV and pulse durations from units to hundreds of microseconds. The article presents the combined results of optical and oscillographic studies. It is shown that the cause of the formation of spark channels during the nonlinear spreading of the pulsed current in the soil, when there is a sharp decrease in the grounding resistance, is the ionization-overheating instability that occurs when the current density on the electrode is greater than the critical one. The development of instability leads to an inhomogeneous current distribution and the appearance of spark channels. On the basis of experimental data, the current-voltage characteristics of the electrodes are obtained.

Computing grounding resistance and impulse impedance of horizontal electrodes parallel or perpendicular to the interface of a vertically stratified soil using transmission line theory

This work shows a procedure to compute the resistance and harmonic impedance of horizontal grounding electrodes buried in a vertically stratified soil. Such electrodes can be parallel or perpendicular to the interface of the vertically stratified soil. An additional resistive element is developed for such condition of soil. A procedure based on transmission line (TL) theory is applied using the developed expressions for grounding harmonic impedance, including different dielectric permittivities for each soil layer. Solutions obtained for slow and fast transients, similar to that from lightning currents, are compared to a rigorous electromagnetic (EM) model. The cases evaluated show a good agreement compared to EM technique, which supports the suitability of the developed procedure, when the procedure premises are a good approximation for the problem. Furthermore, the results for TL procedure agree with the overestimation commonly reported by literature and, for this peculiar soil model, indicate the conditions that are capable to modify significantly the whole behavior of the grounding, i.e., the values of grounding resistance and impulse impedance, for a condition where the interface is parallel or perpendicular to the conductors. The conclusions are supported by the analysis of practical and similar real-world conditions.

An Estimator of the Resistance of Large Grounding Electrodes from Its Geometric Characterization

An estimator of the grounding resistance of large extension electrodes from the total length and geometric properties of the electrode is proposed in this work. The approximation is valid for electrodes buried in a soil that can be assumed as homogeneous and it will be verified that the resistance estimation improves as electrode size increases. Both the burial depth and the radius of the conductors, within certain practical limits, have little effect on the value of the grounding resistance. The shape and size of the electrode are defined by a geometric index that measures the degree of compaction of the conductors that make it up, which has the greatest weight in the final value of the resistance. The expression obtained to quantify the estimate of the grounding resistance is tested in several numerical examples and in a currently operating grounding electrode, obtaining in all cases an estimated value of the resistance reasonably close to the true value.

Analysis on Behavior Grounding Electrode Resistance base on Profiling Method

An earthing system or known as grounding system in an electrical installation where by the grounding system connects specific parts of that installation with the Earth’s conductive surface for safety and functional purposes. It is the process of transferring the immediate discharge with the aid of the low resistance wire of the electrical energy directly to the earth. It is really an important role playing in electrical system part as grounding system give protection during fault or lightning occur. In addition, grounding system also give protection for human electrical appliance and building from electrical shocks due to electrical fault or lighting occur. In this research will shows that to identify the best location to install the grounding electrode. This method is used on 10 x 10 meters which is 121 point will be investigated. The result of 0.3m, 0.6m, and 0.9m were analyzed using MATLAB software to produce profiling and shows the perfect location to install the Grounding system electrode.

Simulasi Sistem Pentanahan Dengan Memodifikasi Konsentrasi Kadar Garam

Grounding system takes a very important role in the electricity and electronics device protection system. The system is used for releasing current disturbance to the ground method. The smaller value of grounding system will give better system. In the certain ground, grounding resistance value is influenced by the depth and distance within the electrodes. The goal of this research is to find the characteristic of rod electrode grounding resistance and design computation method to calculate rod electrode resistance by changing its values and finally it can be used for the protection devices system reference. This research uses three point method to inject AC current into the electrode under test and a current probe and will give a potential between the earth electrode and the potential electrode, so the value of grounding resistance can be found. The result of the analysis indicates that the value of grounding resistance will be smaller when the deep of the planting, the amount of the rod electrode buried and the distance of it are added. The decrease of grounding resistance value will be effective to 75 cm in deep and 300 cm in distance. While planting of rod electrode is deeper more than 75 cm and more 300 cm in distance not effective, because it can reduce the value of grounding resistance which does not have any mean. Therefore, to get the small value of grounding resistance effectively, it is advised to add the amount of the electrode which is planted parallely. With the rod electrode installed before. However, it is important to notice when making the grounding system is the resistivity value of small and great of the ground where the stability of grounding resistance is mounted. Finally, in planting grounding electrode it is important to have the geology data of the ground where the system applied.

Estimation of an Upper Bound to the Value of the Step Potentials in Two-Layered Soils from Grounding Resistance Measurements.

Due to the constant updating of regulatory standards on safety issues in electrical installations, limits are established for the maximum step potential that an installation can hold in a ground fault situation. In this paper, an upper bound to the maximum value of the step potentials arising in the soil surface when a fault takes place in a grounded electrical installation is estimated by means of a simple procedure. The direct measurement of the grounding electrode resistance together with some information about the soil resistivity and the knowledge of characteristic parameters of the electrode are used for the calculation of that upper bound. The procedure is tested at numerical simulation level by using different electrodes in several different scenarios corresponding to two-layered soils with different resistivity ratios. The dependency of the calculated upper bound with the electrode burial depth is also studied. Finally, a real case study is presented, and the results of the field measurements are shown as an example of the validity of the procedure.

A study on copper and galvanized grounding performance using palm oil fuel ash as new additive material

This paper aimed to study the improvement of grounding performance by reducing the grounding electrode resistance using palm oil fuel ash as the backfill. This is achieved by mixing the soil with a specific portion of palm oil fuel ash and obtains the grounding electrode resistance value by using Three Pin Method. In order to obtain the grounding electrode resistance, the mixture of palm oil fuel ash and soil were compacted and installed with electrodes. Two types of electrodes were connected to measuring device which is Kyoritsu Digital Earth Tester Model 4105A and grounding electrode resistance values were displayed. The two types of electrodes used in this study were copper and galvanized steel electrodes. It was found that by adding palm oil fuel ash to the soil, the grounding performance can be improved to at least 90% and above for both copper and galvanized steel electrodes. The palm oil fuel ash is very effective in improving the grounding performance at low cost and environmentally friendly.

Grounding systems under lightning surges with soil ionization for high voltage substations by using two layer capacitors (TLC) model

The grounding system behavior in the time domain for the high voltage substations is the key-parameter to ensure the system reliability during transient conditions. Many approaches are used to investigate the behavior of the grounding systems subjected to the lightning surges. These approaches aim to simplify the grounding systems by equivalent lumped circuit-parameters (RLC) or by using the electromagnetic field theory. The soil ionization phenomenon can effectively reduce the grounding electrode resistance because of changing the electrode equivalent radius located in the soils. Yet, most of these approaches have their relative assumptions with merits and demerits. The current work introduces a proposed model based on a developed grounding unit cell using the Two Layer Capacitors (TLC). The proposed cell is implemented as a unit cell to simulate the performance of the grounding system under lightning strikes with considering the soil ionization effects. Different developed models of the grounding-cells are used to simulate the behavior of the grounding system including the soil ionization process. Finite Difference Time Domain FDTD scheme is used to calculate the electromagnetic fields inside the different proposed unit cells during lightning surges. The application of the grounding unit cell is extended to be implemented for a typical high voltage substation of 500/220 kV. The grounding unit cells are presented as T neighboring sections to evaluate the overlapping between the different elementary electrodes and conductors of the complex grounding systems over the whole area of the substation. The circuit-model of the grounding unit cell is developed using EMTP-RV/MATLAB. Finally, the obtained results are compared with the similar results found in the literature with good consistency.

Improvement of safety of autonomous electrical installations by implementing a method for calculating the electrolytic grounding electrodes parameters

We have solved the task of safety improvement in the grounding process of autonomous mobile electrical installations. Existing procedures for the calculation of normalized resistance of grounding electrodes in electric installations have been examined and studied. Their main drawbacks have been revealed: the difficulty and complexity of calculations; the probabilistic and approximate character; the use of source data taken to calculate the electrophysical parameters of stationary grounding electrodes; the calculations do not account for the structural-phase structure of soil and the volume of electrolyte. Based on the application of percolation theory and the apparatus of fractal-cluster geometry, we have modeled the process of electrolytic grounding in heterogeneous soils of different porous structure, which possess the percolation and fractal properties. A physical model of the process of electrolytic grounding has been developed, which takes into consideration the soil structure properties when changing the fractal dimensionality of a cluster over a certain range that forms the electrolytic grounding conductor with the normalized resistance. It has been shown that the model of conductivity of the electrolytic grounding electrode is defined by the soil electrical conductivity in a percolation channel of the porous structure of soil and can be considered as a function of the volumetric concentration of the electrolyte and the size of the volumetric structure of the electrolytic percolation cluster. We have derived analytical expressions to relate the normalized resistance of electrolytic grounding conductors and the specific resistivity of soil to the fractal dimensionality, volume of the electrolyte, the number of pores to the electrolyte, density of a geometrical volumetric body. We have improved a method for calculating the electrophysical parameters of electrolytic grounding conductors, based on accounting for the main linear size of the cluster of an electrolytic volumetric body, which coincides with the electrolyte penetration depth for various soil structures. We have established conditions for conductivity of the electrolytic grounding conductor in order to ensure safety during operation of the autonomous mobile electrical installation

Integration of Energy Balance of Soil Ionization in CIGRE Grounding Electrode Resistance Model

This paper proposes an improved CIGRE grounding electrode resistance model by integrating the energy balance of soil ionization. The main contribution of the improved CIGRE model is its accuracy to compute the time-dependent grounding electrode resistance under impulse condition. In addition, it can obtain correct resistance–current relation (hysteresis characteristic) of the grounding electrode. The accuracy of the improved CIGRE model is achieved by taking into account the effect of the arc resistance in soil, considering the energy balance of the soil ionization. The improved CIGRE model was validated for low resistivity soils ranging from 40 to 370 Ω·m. The comparison of the computed grounding electrode resistance obtained from the improved CIGRE model and experiment confirms the increase in the accuracy of the resistance and voltage response of the grounding electrode. The grounding electrode resistances obtained from the improved CIGRE model and experiments at current peak and current half value at decaying period (tail) have shown maximum differences of 3.5 and 2%, respectively. Moreover, precise voltage responses of grounding electrodes compared with the experimental results were obtained under different impulse currents.

The Calculation of Corrective Coefficient for Grounding Electrode Resistance according to Variation of Soil Resistivity by Field Measurement

The Calculation of Corrective Coefficient for Grounding Electrode Resistance according to Variation of Soil Resistivity by Field Measurement

An Estimate of the Uncertainty in the Grounding Resistance of Electrodes Buried in Two-Layered Soils with Non-Flat Surface

The influence of the irregular surface of a multi-layered soil on the estimation of the ground resistance of a complex electrode is studied. The electrode is placed in the first layer while the irregular surface is treated as the interface of an inhomogeneous volume filled with air and embedded in the first layer. A wide sample of irregular soils is generated and the variation of the electrode grounding resistance, as a function of a parameter that measures the surface unevenness, is evaluated. A stochastic model of the grounding resistance is proposed for which the variation of the electrode grounding resistance with its horizontal position relative to the surface is studied. The model features allow us to explain the variability found, as we are able to estimate the part of the uncertainty about the electrode grounding resistance measurements due to the non-planar soil surface.

Preliminary result on the enhancement of Ufer electrodes using recycle additives materials

Ground building pillars is to be used as ground rod. The pillars are design, fabricated, and formulated with new ground fillers. The additives will be used from recycle waste materials mainly from the palm oil plant process. Micro scale building pillars will be fabricated and install in the test ground at all of the location. Earth tester meter are used to measure and collect the data of the soil resistivity when the research is conducted. In collecting these data, 3-terminal methods are used to carry the measurements. This experiment will be conducted for 30 weeks and regular measurements at the test ground copper grids will be conducted to measure the ground electrode resistance. The study will mainly base on IEC 62503-3. The used of reinforcing rods and mixture of recycle additives could produce a better grounding system that are suitable and can be used in all kind of soil condition and large industries.

Effect of electrode shape on grounding resistances — Part 1: The focus-one protocol

Electrode grounding resistance is a major factor affecting measurement quality in electric resistivity tomography (ERT) measurements for cryospheric applications. Still, little information is available on grounding resistances in the geophysical literature, mainly because it is difficult to measure. The focus-one protocol is a new method for estimating single electrode grounding resistances by measuring the resistance between a single electrode in an ERT array and all the remaining electrodes connected in parallel. For large arrays, the measured resistance is dominated by the grounding resistance of the electrode under test, the focus electrode. We have developed an equivalent circuit model formulation for the resistance measured when applying the focus-one protocol. Our model depends on the individual grounding resistances of the electrodes of the array, the mutual resistances between electrodes, and the instrument input impedance. Using analytical formulations for the potentials around prolate and oblate spheroidal electrode models (as approximations for rod and plate electrodes), we have investigated the performance and accuracy of the focus-one protocol in estimating single-electrode grounding resistances. We also found that the focus-one protocol provided accurate estimations of electrode grounding resistances to within [Formula: see text] for arrays of 30 electrodes or more when the ratio of instrument input impedance to the half-space resistivity was [Formula: see text] or more. The focus-one protocol was of high practical value in field operations because it helped to optimize array installation, electrode design, and placement. The measured grounding resistances may also be included in future inversion schemes to improve data interpretation under difficult environmental conditions such as those encountered in cryospheric applications.

The effect of soil ionization on transient grounding electrode resistance in non-homogeneous soil conditions

The soil ionization phenomenon effectively reduces the grounding electrode resistance. The existing methods to determine the soil ionization effect on the transient resistance of a grounding electrode are valid only for homogeneous soils. However, most soil structures are non-homogeneous. Realizing the importance of the issue, this study proposes a hybrid method to incorporate the soil ionization effect on the transient resistance of a grounding electrode located in non-homogeneous soil condition. The electromagnetic field approach is utilized to compute the ionized soil volume around the electrode to determine the equivalent radius of the electrode. A circuit-based method of computing the grounding resistance of the electrode in non-homogeneous soil conditions is proposed based on the per-unit-length distributed parameter method. The proposed method is validated by using an electromagnetic field-based numerical solution for the non-homogeneity effect of the soil on grounding electrode resistance.

The Effect of Grounding Electrode Parameters on Soil Ionization and Transient Grounding Resistance Using Electromagnetic Field Approach

The soil ionization phenomenon occurs during the dispersion of lightning current into the earth. This phenomenon causes the grounding electrode resistance to be effectively reduced. The extension of the soil ionization depends on the current amplitude along the electrode and the resultant electric field intensity surrounding the electrode. The electrical and physical parameters of the grounding electrode system are found as factors that affect the electric field intensity. In this study the electromagnetic field approach and the soil breakdown theory are taken into account to investigate the effect of the mentioned factors on soil ionization and grounding resistance. Changing the parameters of the grounding electrode system affect the electric field distribution around the electrode. Based on the conditions the grounding electrode resistance was reduced between 12% to 75% by considering the soil ionization effect.

20 kHz 전력설비 접지시스템 분석에 관한 연구

In this paper, carried out for optimal ground system for ensuring safety for electricity used to power equipment in the 20 kHz frequency. Now the grounding system of the mesh electrode, electrode rods are installed for power plant safety and protection against electric shock. However, the electrical equipment grounding system in the 20 kHz were considering the increasing grounding impedance due to the high frequency and the magnetic shielding. But until now, there has been little research on the grounding system. To solve this problem, In this paper was proposed optimal grounding system due to the experiment using a mesh electrode, rod electrode, aluminum plate electrodes. Measurement results, grounding resistance was depending on the material of the electrode grounding resistance. In addition, the leakage current (induced) appeared to be affected depending on the type of electrode.

Grounding Resistance of Electrode for Electrical Landfill Leakage Detection

The grounding resistance of power electrode plays a decisive role on the source current in landfill leakage detection using electrical method. A model of grounding resistance for cylindrical electrode was set up in this paper. The corresponding resistance expression was derived, and the main influence factors were also analyzed. The results show that: 1) the electrode grounding resistance is mainly determined by the resistivity of surrounding soil; 2) as the buried depth and the diameter increase, the electrode grounding resistance reduces. When the buried depth exceeds 40cm, the electrode grounding resistance is slightly influenced by the buried depth. Therefore, the buried depth and radius of power electrode should be as large as possible in practice. In addition, the soil around the power electrode should be watered to reduce the grounding resistance. Experiments validate the conclusions.