Installation Of Arresters Research Articles

Analysis of Determining the Surge Arrester Protective Distance for Protection on 60 MVA Power Transformers at the 150 KV Main Substation in Surabaya Barat

Because it provides electrical energy to customers that require protection from lightning interference, the substation is a crucial location. An electrical equipment's defense against lightning strikes is provided by a lighting arrestor. The arrester should be placed as near to the transformer as feasible for optimal protection. In order to restrict the installation of arresters to safeguard equipment, the maximum distance for arrester installation must be established. This study only looks at one 60 MVA transformer in the Surabaya Barat Main Substation, and its goal is to determine the minimum amount of error in transformer protection. Based on the maximum possible surge arrester surge arrester jarak with a power transformer at the Surabaya Barat Main Substation, the maximum possible surge arrester distance is 8,135 meters. Based on surge arrester capability, the transformer may be protected from over voltage since the maximum voltage that can occur is just 150.83 kV, with the maximum voltage remaining below the transverse impulse drop of around 650 kV.

Influence of a shield wire flashover on the indirect lightning performance assessment of distribution lines

This paper presents a new aspect of shield wire (SW) modeling for assessing the indirect lightning performance of overhead medium-voltage distribution lines: a flashover (FO) between an SW and the reinforcing bars of a distribution pole or a crossarm (SWFO). In general, an SW is periodically grounded approximately every four to ten poles and not grounded at the other poles. However, owing to lightning-induced overvoltages, the voltage difference between the SW and the distribution pole may even exceed 100 kV, and the SWFO can occur. In this paper, we evaluate the effect of the SWFO on the number of FO occurrences of phase-conductor insulators by the Monte Carlo method using a 2D finite-difference time-domain-based indirect lightning surge analysis program. The effect of the SWFO is more significant in lines with high soil resistivity (a soil resistivity of 1000 Ωm was assumed) regardless of the installation of surge arresters: the total number of FO occurrences markedly differs by up to 50% between cases in which the SWFO is considered and not considered. The analysis presented in this paper will assist the formulation of lightning protection measures particularly, in regions with high-resistivity soils.

Mitigation of Insulator Lightning-Induced Voltages by Installing Parallel Low-Voltage Surge Arresters

In this paper, we propose a mitigation method for reducing lightning-induced insulator voltages based on the installation of low-voltage surge arresters aligned parallelly to the insulator. The three-dimensional finite-difference time-domain (FDTD) method is applied to numerically model a real surge arrester residual voltage evaluation system. The application of a transient current pulse, typical of lightning discharges, is considered in our numerical model. We considered cases with one or two surge arresters installed per phase, in three different geometric and parametric configurations for installing distribution surge arresters. In addition to the Kirchhoff current division, which reduces both the absorbed energy and the thermal stress, the results associated with the installation of two surge arresters parallelly aligned to the insulator show that the interaction of magnetic fields generated by the surge arresters’ currents can produce an additional strong reduction in lightning-induced voltage over the insulator, as presented in this paper. Conditions for maximum voltage reduction are also identified. A brief cost-effectiveness analysis is also provided.

Investigation of line surge arresters application to the 150 kV system of Rhodes

• The application of line surge arresters to 150 kV overhead lines is investigated. • The required energy absorption capability of line surge arresters is determined. • Non-gapped line arresters and externally gapped line arresters are compared. • Surge arrester installation configurations are evaluated for critical lines. • Lightning performance improvement of a critical 150 kV overhead line is quantified. This paper investigates the application of Line Surge Arresters (LSAs) to 150 kV double-circuit overhead lines through ATP-EMTP simulations. The 150 kV lines under study are the backbone of the autonomous electrical system of Rhodes island in southeastern Aegean Sea, Greece. Hence, lightning-related insulation flashovers causing outages of these lines may lead to a blackout of this isolated system. In this work, both Non-Gapped Line Arresters (NGLAs) and Externally Gapped Line Arresters (EGLAs) are evaluated. Two installation configurations with 3 and 6 LSAs per tower are considered protecting one circuit and both circuits of the line, respectively. Simulations were performed for both lightning strikes to phase conductors and tower; these may cause shielding failure flashover and backflashover, respectively. The conducted current through the LSAs and the voltage at their terminals are computed, enabling the estimation of the energy stressing the LSAs. The effects of the lightning current time to half value, the phase angle of the operating voltage, and the power frequency ground resistance of towers are assessed. The required LSA energy absorption capability is determined. The lightning performance of a critical overhead line of the Rhodes 150 kV system is estimated and its improvement due to LSA installation is quantified.

Lightning Performance Improvement Of 123 kV Line Ston – Komolac By Use Of Line Surge Arresters

This paper presents HEP - Transmission System Operator Ltd. Line surge arrester (LSA) application pilot project on the Ston – Komolac 123 kV line. This 44 km long single circuit shielded transmission line operates in the region with a high lightning activity (keraunic level about 70 thunder days). In addition, it was very difficult to obtain good footing resistance. For these reasons, considered line used to have very bad lightning performance. It was decided to install Line surge arresters for line lightning performance improvement. In order to optimize arrester installation configuration sigma slp software simulations were performed. LSA are installed according to the results of the software simulations. LSA are installed in summer 2007 (110 gapless, IEC-class II Line arresters). Sixty one LSA are equipped with Excount - II monitoring sensors (monitoring arrester leakage current and peak of the impulse current). Based on the 8-month experience, LSA installation has improved line lightning performance. New line performance is close to the targeted once (improvement by 50 to 60 %). Surge arrester monitors collect very interesting information. Collected info will be compared with the software simulations.

The Possibility of Insulation Level Reduction on 110 kV Overhead Line with Built-in Post Insulators Using Line Surge Arresters

Installation of line surge arresters (LSA) on overhead lines is normally accomplished with aim of line performance improvement. Co-ordination insulation procedure carried out during the line design in most cases doesn't take into account a suppression of overvoltages by using any overvoltage limiting devices. The decision supported by poor line performance to install LSA is usually made later. The reduction of overvoltage level depends mainly on the number of LSA installed, but in any case it is considerable. It means that insulation regarding dielectric strength might this way be over dimensioned. This fact could be considered for reduction of phase-to-ground and phase-to-phase distances, which lead to greater level of line compaction. This is of the most importance for lines with post insulators, since shorter insulators could be used and consequently narrower right of way achieved. Our target was to investigate the possibility of reducing lightning overvoltages by using LSA’s attached parallel to the insulators. For the analyses purpose we implemented a mathematical model of a single-system 110 kV compact overhead line. The Sigma Slp software was used for computer simulations. The line was investigated from the perspective of lightning over-voltages as they are the factors the most severely stressing the insulation. We focused to lightning strikes at a tower top for the case of single-phase (C) LSA installation configuration. The main influencing parameters were varied such as lightning current, surge shape and tower earthing resistance according to their most probable values to obtain overvoltage properties. We concluded, that adoption of LSA’s does not only reduce the overvoltage amplitude in that phase but also changes its shape, which has to be taken into account for test impulses generation. The physical model of wooden pole with composite line post insulators was built for testing in high-voltage laboratory. Power frequency and impulse tests were performed on insulators (phase-to-ground) and between phase conductors (phase-to-phase) in dry and wet conditions when necessary. Besides standard also non-standard impulse shape tests were accomplished to obtain withstand voltages for different arching distances. Based on our comparison with the simulation results we concluded that - speaking in terms of lightning overvoltages - it is possible to use insulators for the insulation level Um = 72,5 kV (140/325 kV), if LSA’s in phases A, B and C would be installed. To verify the conclusion in all other respects, further analyses are needed.

Line Surge Arresters Applications On The Compact Transmission Lines

This paper presents application of line surge arresters on the compact transmission lines. Single and double circuit compact transmission lines are considered. Line lightning performance is computed using sigma slp simulation software. Different line surge arrester installation configurations are considered. Line lightning performance is computed for different tower footing resistance. Line performance before and after line surge arrester installation are compared. Line lightning performance of the unshielded line with line surge arresters is compared with the performance of the shielded line without line surge arresters. For double circuit shielded compact lines, double circuit outage rate is computed. Influence of the tower footing resistance on the double circuit outage rate is presented.

Risk management of cable termination faults and effective maintenance using partial discharge (PD-LT) device

One of the most important equipment in distribution networks is cable termination. The widespread use of this equipment makes it one of the most important equipment in the electricity industry and at the same time, it includes a major part of the causes of outages in power networks. For example, in 2021, this equipment is the second influential factor in the amount of undistributed energy and the increase of the SAIDI index in Isfahan Electricity Distribution Company and Conventional methods such as periodic inspections and imaging using thermovision cameras and the installation of surge arresters and the construction of parallel earths, etc. has not a significant impact on detecting faulty cable terminations and preventing outages. In this paper, an attempt has been made to obtain a solution to identify and prevent defects in cable terminations and joints by using Partial Discharge measurement by measuring the magnetic field and converting it into an audio unit by a PD-LT device. Initially, 720 cable terminations in the city of Baharestan1 were tested and analyzed. The information obtained was analyzed by Power BI software, which led to the prediction of the useful life of the tested cables. The amount of partial discharge can be a good indicator to measure the risk of failure in distribution networks.

Variasi Nilai Tegangan Percik Arrester Akibat Pengaruh Kapasitas Trafo Daya dan Jarak Arrester

The ability of each substation to withstand lightning and overvoltage affects the power distribution of the power system. In order to make the best operation of the substations, it is necessary to install Arresters which are used to protect the transformers in each substation from overvoltage caused by lightning surges. In this study, the effect of capacity on the placement distance of the arrester is discussed with 30 MVA and 60 MVA transformers. The purpose of this study was to determine the effect of the power transformer capacity of the four substations on the value of the arrester spark voltage and to obtain the optimal arrester installation technique at each substation using the Lagrange optimization method. Lagrange optimization method is used to determine the optimal distance between the arrester and the power transformer. The calculation results show that in a transformer with a capacity of 60 MVA, the Arrester spark voltage occurs at t = 20 microseconds with a voltage drop of 390.49 kV. Meanwhile, in a transformer with a capacity of 30 MVA, the Arrester spark time is at t = 13.9 microseconds with a voltage drop of 266.3 kV. This shows the capacity of the transformer that affects the magnitude of the Arrester's spark voltage and the spark time. Thus, the smaller the transformer capacity, the smaller the arrester spark time with the large voltage drop

Optimal placement of surge arresters for transmission lines lightning performance improvement

Installation of transmission line surge arresters (TLSA) is one of the solutions found to improve the lightning performance of overhead transmission lines (OHTL). This work proposes a new multi-criteria methodology for the optimal placement of surge arresters on OHTL based on a multi-objective optimization algorithm coupled with ATP (Alternative Transient Program) software. Lightning performance calculation is performed considering the transfer effect of the lightning surge due to arresters operation. This transfer mechanism that can lead the adjacent towers to flashover is rarely mentioned in the literature. A case study considering a 230 kV transmission line with 231 towers and 105 km long operating in Brazil is presented. Compared to the real performance data, the solution found with the best cost-benefit ratio allows a reduction of 68% in the line outages with the use of 90 surge arresters (i.e., 0.86 TLSAs/km of line). This is practically 50% of the number of arresters calculated using the classical placement method based on the tower-footing impedance value. Regarding the transfer effect of the lightning surge, the results show that the performance levels and, consequently, the number of TLSAs to protect the line may be underestimated if this effect is not considered in the modelling.

Techniques for the improvement of the lightning back-flashover performance of double circuit HVDC lines

This paper addresses different issues regarding the lightning back-flashover performance of HVDC lines, especially regarding double-circuit configurations. In such configurations, two poles may present very similar flashover risks due to a lightning strike, leading to a double flashover. Therefore, it is of particular interest to investigate solutions to protect at least one circuit from flashovers and avoid the temporary loss of the transmitted power and the associated consequences to the system. In this work, electromagnetic transient models are implemented to investigate two solutions for the improvement of the lightning performance: the installation of surge arresters and the use of unbalanced insulation. The results are analysed thoroughly and the mechanisms and theoretical bases behind them are explained. In addition to the grounding resistance of the tower, the coupling between the conductors and the DC pole configuration within the tower also play a major role in determining the lightning back-flashover performance of a double circuit HVDC line. The installation of a single arrester can achieve a very significant improvement of the overall lightning performance of a tower. A proper implementation of an unbalanced insulation solution is very effective in limiting the incidence of double flashovers while maintaining an optimal overall performance.

Experimental study on detonation propagation in industrial scale pipelines used in petrochemical plants

Based on the lack of systematic research on flame propagation in large-diameter and long-distance pipelines in the tank area of petrochemical plants, an experimental device for flame propagation in DN50-DN500 industrial-scale pipelines was designed and built. In this paper, effects of concentration of gas mixture for propagation characteristics of steady gaseous detonation waves in ethylene-air mixtures with DN50 pipeline were studied experimentally. The volume concentration of gas mixture was 5.6%, 5.93%, 6.6%, 7.15%, 8.0% ethylene in air. Homogeneous C2H4/air (6.6%) and C3H8/air (4.2%) mixtures were used with 9 kinds of pipelines which were from DN50 to DN500 to study the effects of pipeline diameter for propagation characteristics of steady gaseous detonation. The experimental results show that the concentration of combustible gas has an effect on flame propagation and detonation. The detonation runup distance is short and steady detonation is more likely to be formed when it is close to chemical equivalent concentration, when the combustible mixture is poorer or richer, the steady detonation will need more runup distance. The detonation flame speed and pressure are more affected by the type of combustible gas instead of pipe diameter. The detonation pressure of the mixture of 6.6% C2H4/air and the mixture of 4.2% C3H8/air is 15.17 and 14.47 times of the initial pressure, respectively, which is different from the reference value given by the ISO16852 standard where the ratio pm/p0 (the average value of the detonation pressure to initial pressure) increases with pipe diameter. The detonation pressure of pipeline below DN150 is far higher than the reference value which is 10 and 12. It’s suggested that in the design of pipelines and selection and installation of flame arresters for connecting pipelines in the tank areas, detonation pressure requires careful consideration and appropriate arresters should be selected in combination with the installation position.

Comparison of Backflashover performance between a novel composite pylon and metallic towers

A design of a fully composite pylon with external grounding down-leads has been proposed for new-generation 400 kV transmission towers, able to save lines corridors and to reduce visual impact. This paper investigates and compares the backflashover performance of a composite pylon and two conventional metallic towers, which have been widely installed in Denmark. The transient models of overhead lines and all three towers were established respectively and the transient analysis was carried out in PSCAD. Monte Carlo method was used to estimate backflashover rate. The backflashover rate of composite pylon is 0.4526 cases per 100 km per year, which is in the same range, but slightly higher than that of metallic towers. The separated grounding down-leads of double circuits on composite pylon eliminates the danger of simultaneous backflashover of double circuits, which exists in transmission lines supported by metallic towers. After comparing the overvoltages to three phases of the three towers from backflashover, it is worthy considering that the installation of surge arresters at all three phases of composite pylon has a strong impact on the backflashover rather, but for the two metallic towers only the surge arresters at the upper phase has an impact.

Studi Kemampuan Arrester Untuk Pengaman Transformator Pada Gardu Induk Tanjung Morawa 150 KV

Overvoltage is a voltage that can only be held for a very limited time. Overvoltage that occurs for a time that exceeds the equipment's capacity limit will damage the equipment connected to the network that is subjected to overvoltage. Lightning overvoltage is a periodic overvoltage caused by external overvoltage, both direct and indirect strikes. Lightning overvoltage only lasts a very short time but has a voltage that is so high that it exceeds the operating voltage of the equipment so it is potentially very damaging. Lightning Arrester is an installation safety equipment from overvoltage disturbances due to lightning strikes (Lightning Surge) or by switching surges (Switching Surge). Transformer / power transformer serves to distribute power / electrical power by increasing or decreasing the voltage at the substation. This research focuses on substation equipment, namely Lightning Arrester ASEA type XAR 170A3/144 which is connected to a Power I transformer (transformer) UNINDO 906007289. Good protection is obtained when the arrester is placed as close as possible to the transformer clamp. However, in practice the arrester must be located at a distance X from the transformer being protected. Therefore, the distance must be determined properly so that the resulting protection can be obtained properly. Arrester installation according to theory is 50 meters from the transformer, in practice at the TAMORA Substation the arrester distance is 3 meters from the temporary transformer based on calculations in this final project the best distance is 10.96 meters.

Desain Pemrograman Visual Pengendalian Nomor Urut

Overvoltage is a voltage that can only be held for a very limited time. Overvoltage that occurs for a time that exceeds the equipment's capacity limit will damage the equipment connected to the network that is subjected to overvoltage. Lightning overvoltage is a periodic overvoltage caused by external overvoltage, both direct and indirect strikes. Lightning overvoltage only lasts a very short time but has a voltage that is so high that it exceeds the operating voltage of the equipment so it is potentially very damaging. Lightning Arrester is an installation safety equipment from overvoltage disturbances due to lightning strikes (Lightning Surge) or by switching surges (Switching Surge). Transformer / power transformer serves to distribute power / electrical power by increasing or decreasing the voltage at the substation. This research focuses on substation equipment, namely Lightning Arrester ASEA type XAR 170A3/144 which is connected to a Power I transformer (transformer) UNINDO 906007289. Good protection is obtained when the arrester is placed as close as possible to the transformer clamp. However, in practice the arrester must be located at a distance X from the transformer being protected. Therefore, the distance must be determined properly so that the resulting protection can be obtained properly. Arrester installation according to theory is 50 meters from the transformer, in practice at the TAMORA Substation the arrester distance is 3 meters from the temporary transformer based on calculations in this final project the best distance is 10.96 meters.

Lightning Overvoltage Protection of Step-Up Transformer Inside a Nacelle of Onshore New-Generation Wind Turbines

This paper presents an electromagnetic transient analysis of lightning-initiated overvoltage stresses of the step-up transformers installed inside a nacelle of onshore, multi-megawatt, new-generation wind turbines. The increase in the wind turbine (WT) nominal power output, necessitated introducing the step-up transformer into the nacelle. A transformer installed inside a nacelle is subjected to completely different overvoltage stresses from those present if it were installed at the base of the WT tower. This has serious repercussions on its overvoltage protection (i.e., selection and installation of surge arresters) and insulation coordination. Furthermore, the overvoltage protection of medium-voltage cables (inside the tower) is also problematic when considering their length, proximity to the tower wall, and their screen grounding practices, and needs to be tackled in conjunction with that of the step-up transformer. This paper presents detailed models for the various components of the latest-generation WTs, intended for fast-front transient analysis and assembled within the EMTP software package. We further present the comprehensive results of the lightning-transient numerical simulations, covering both upward and downward (first and subsequent) strikes, their analysis, and recommendations for the optimal selection of medium-voltage surge arresters for the step-up transformers installed inside a nacelle.

Lightning Performance Evaluation of Transmission Line Based on Data-Driven Lightning Identification, Tracking, and Analysis

Lightning performance evaluation is aimed at classifying transmission lines into different risk levels of thunderstorm-induced trip-out. Its applications range from better lightning protection guidance, arrester installation design, transmission line retrofits, and line corridor design. Previous studies fail to consider the real-time lightning intensity, which is an essential factor of lightning trip-out that must not be ignored. This article proposes a novel lightning performance evaluation model based on the idea that the tower, which has a record of lightning trip-out with weaker real-time lightning intensity, is more susceptible to trip out, which means low lightning performance. In order to quantify the lightning intensity, this article puts forward a new definition of lightning intensity which includes three kinds of real-time characteristics, that is the location, the current of lightning strike, and the number of times the lightning movement track crosses the transmission line. More specifically, with the rapid development of lightning location system, a novel Lightning Identification, Tracking, and Analysis algorithm is proposed to search lightning movement track based on a database of 17 million lightning records. When lightning trip-out happens, the lightning performance level is graded according to the real-time lightning intensity. By comparing the similarity of static characteristics, the lightning performance level is extended to the tower, which has no record of lightning trip-out. By comparison with the traditional model, the proposed model is closer to the actual situation and can significantly improve the accuracy of lightning performance evaluation, which is improved by 66.7%.

Optimized Surge Arrester Allocation Based on Genetic Algorithm and ATP Simulation in Electric Distribution Systems

The efficient protection of electric power distribution networks against lightning discharges is a crucial problem for distribution electric utilities. To solve this problem, the great challenge is to find a solution for the installation of surge arresters at specific points in the electrical grid and in a sufficient quantity that can ensure an adequate level of equipment protection and be within the utility’s budget. As a solution to this problem of using ATP (Alternative Transient Program), this paper presents a methodology for optimized surge arrester allocation based on genetic algorithm (GA), with a fitness function that maximizes the number of protected equipment according to the financial availability for investment in surge arresters. As ATP may demand too much processing time when running large distribution grids, an innovative procedure is implemented to obtain an overvoltage severity description of the grid and select only the most critical electric nodes for the incidence of lightning discharges, in the GA allocation procedure. The results obtained for the IEEE-123 bus electric feeder indicate a great reduction of flashover occurrence, thus increasing the equipment protection level.

Reduction of the number of faults caused by lightning for transmission line

In this paper, author proposed an algorithm to determine method which is used to reduce the fault number caused by lightning on a transmission line. The algorithm is developed based on three methods including increase in the insulator string length, surge arrester installation, and surge arrester installation in combination with increase in the insulator string length. The output of algorithm is the proposed method which makes the number of faults caused by lightning satisfy the requirement and its investment is the cheapest in them. Based on this algorithm, the reasonable method (the number of tower positions needing to improve) to reduce the number of lightning caused faults of the transmission line can determine if we know the ratio of the required number lightning caused faults to the current value. This algorithm is applied to a transmission line to propose an improving method so that the fault number satisfies the requirement. This algorithm is implemented to a 220kV transmission line. The calculation results show the reasonable method and it also indicates in detail which towers should install surge arrester, which towers should increase the insulator string length.

Optimal Surge Arrester Placement for Extra High Voltage Substation

Lighting Phenomena is one of the important considerations during the design of Extra High Voltage and Ultra High Voltage Transmission Lines. Most of the authors have discussed regarding the benefits of using Surge Arresters as a way to improve the performance. In this paper, simulation analysis is done on 400kV/220kV Gwaka Substation, AP, India for optimal, cost effective placement of surge arresters. The most difficult configuration has been identified. A new method of “Voltage-Distance curve” is proposed to evaluate different Surge Arrester installation configurations. Finally the way to determine the optimal surge arrester configuration for each line section is then introduced in this paper.