Different Types Of Insulators Research Articles

Comprehensive Analysis of Insulator Performance in High Voltage Transmission Systems: Implications for Efficient Power Transfer

This research article examines the performance of insulators in high-voltage transmission systems, specifically focusing on their role in facilitating efficient power transfer along transmission lines. The study evaluates different types of insulators used in various geographical regions and assesses their withstand voltage characteristics. The research demonstrates that glass insulators outperform plastic and ceramic insulators in terms of electric field behavior. The study also investigates the behavior of AC-energized insulators in polluted and non-polluted conditions, providing insights for improving HVAC insulation design in polluted environments. The research recommends further experiments to examine insulator behavior under different applied voltage scenarios. Overall, the study emphasizes the importance of insulators in high-voltage transmission systems and provides valuable insights for developing advanced insulator technologies to enhance power transfer efficiency.

Environmental Effects on Parameters of Leakage Current Equivalent Circuits of Outdoor Insulators

The performance of outdoor insulators in transmission lines may deteriorate due to aging and can even be enhanced by the presence of pollutants. Leakage current (LC) measurement is one of the most effective methods to diagnose the insulator condition, utilizing LC parameters such as magnitude and total harmonic distortion (THD). However, research on the interpretation of these parameters is still limited. This paper discusses the diagnostic method by simulation, employing the LC equivalent circuits of different types of insulators and examining the influence of environmental factors, such as humidity and pollutant levels. LC waveforms are first obtained through experiments on various insulator types, including traditional ceramic and glass insulators, advanced composite insulators, or the hybrid type of RTV silicone rubber-coated and conducting glazed insulators. Subsequently, simulations on the LC circuits of Suwarno’s and Kizilcay’s models are performed to obtain similar LC waveforms and properties. The values of the equivalent circuit parameters are then used to diagnose each insulator’s characteristics and environmental effects. The results indicate that composite insulators of epoxy resin or SiR have a larger intrinsic resistance of ~40 GΩ and nonlinear resistance (a few MΩ to tens of GΩ), representing high surface resistance of the insulators against water and pollutants. A comparison of these parameters is expected to indicate the severity levels of insulator condition. Doi: 10.28991/ESJ-2024-08-01-022 Full Text: PDF

Method of calculation of temperature parameters and service life of 10 kv cable lines

This study is based on the analysis of the methodology for calculating the temperature parameters of 10 kV cable lines and calculating the service life of insulation under various operating conditions, as well as identifying dependencies that allow the most accurate selection of cable parameters during operation at industrial facilities. The results of the study can be used to improve the energy efficiency of enterprises, and contribute to reducing the number of emergency failures of cable lines that may occur due to thermal breakdowns caused by incorrect choice of cable parameters under certain operating conditions, which may cause an increase in production costs in general. Conducting research and calculations of temperature parameters of cable lines at a voltage of 10 kV with different laying methods and with different capacity factors according to the climatology of the Republic of Tatarstan, as well as identifying key dependencies that will enable to draw appropriate conclusions on the operation of cables in the conditions under consideration. The article uses methods for calculating temperature parameters and cable service life, as well as methods for processing the data obtained as a result of calculations, including the method of function approximation. Special software is also used to visualize the results obtained after the calculations. The results of calculations of temperature parameters of 10 kV cable lines for various laying methods, with different types of insulation and with different capacity factors according to climatology of the Republic of Tatarstan are presented. Calculations of the service life of cable lines under the conditions under study have been made and conclusions have been drawn on optimal cable loads that will not lead to premature thermal aging of insulation under certain operating conditions. The initial data for the calculations and the methodology used comply with GOST standards for cable lines. The results of the study and the calculations performed can be used to evaluate and select the optimal load of cable lines under selected conditions at the design stage of power supply systems.

FIELD EXPERIMENTAL INVESTIGATION OF THE INSULATION DETERIORATION CHARACTERISTICS OF OVERHEAD PIPELINE FOR STEAM HEATING NETWORK

The thermal insulation performance of pipeline is significant for the safety and economical operation of vapor steam network. In order to investigate the long-time insulation performance of pipeline, a field test was carried out in pipelines of 12 different heating networks with the operating time ranging from 1 to 11 years. Two different types of insulation coating layer were included. The total heat flux and surface heat flux in a pipeline were measured to obtain the equivalent thermal conductivity of the insulation coating layer, and a deterioration coefficient was applied to analyze the insulation deterioration characteristics. The results show that the one-dimensional thermal conduction method is feasible to calculate the heat flux of the pre-manufactured pipeline with hard insulation materials, and an error less than 2% for pipeline 1 was obtained. Further, a proper size of slip in the insulation coating layer has improved the insulation performance by 13.6% in pipeline 2. For the soft type insulation coating, the structure has been changed under the long-term effect of gravity. Accordingly, a single thermal conductivity cannot accurately characterize the heat transfer process within the insulation layer. The surface heat flux accounts for less than 30% of the total heat loss. The insulation deterioration trend with operating time cannot exactly be obtained by the surface heat flux. In addition to the thickness reduction at the top and hollow at the bottom, the convection heat leakage from the gaps should also be a concern for long time operation.

FEM Analysis of the Electric Field and Potential of Various Types of Insulators under Uniform Pollution

This work aims to present an analysis of the behaviour of the electric field and the potential for three different types of insulators, the glass, the porcelain and the polymeric. Since pollution is an important factor for their insulation performance and reliability in high-voltage systems, it is essential to understand how a uniform pollution layer could influence the distribution of the field and the electric potential for each of these insulators. For this purpose, COMSOL Multiphysics was used to study these distributions in both clean and polluted conditions, using the finite element method. The results show that the uniform pollution layer reduces the distribution of the electric field of insulator. Keywords: COMSOL Multiphysics; electric field; finite element method; glass insulator; porcelain insulator; silicone insulator; uniform pollution

Thermal Evaluation of Silica-Based Insulated Magnet Wires from the Sol-Gel Process.

The conventional enameling process used in the fabrication of magnet wires requires harmful processes and products. The target of the industry in the actual context of electrification is to increase the electrical machines' efficiency. Indeed, the electrical insulation systems (EIS) of an electrical machine undergo various environmental constraints that can shorten their lifespans. Consequently, aspects of the insulation need to be improved, such as its thermal resistance. One of the challenges is to implement sustainable technology without losing performance. This work consists of the thermal performance evaluation of new magnet wires insulated by three types of composites of silica-based solution from the Sol-gel process and amorphous polyamide-imide (PAI). These composite coats are overcoated by an extruded thermoplastic resin with and without fillers. Different types of insulation are tested and compared to determine the better configuration. Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) analysis, scanning electron microscopy (SEM) analysis, curing characteristics by tangent delta curve, and thermal-aging tests at three temperatures were carried out on the different EIS systems. Dielectric measurements were made between thermal-aging cycles. Their basic mechanical, electrical, and thermal characteristics are promising: the cut-through temperature is situated above 430 °C, their breakdown voltage values are between 5 kV and 9 kV (grade 3), and a good adhesion (overcoming more than 140 turns on a peel test). The thermal-aging results have been consistent with the TGA analysis results. The thermal index following the IEC standards was estimated for the selected EIS, which would have the main basic characteristics of a magnet wire of 200 class; moreover, it would be a greener enameled wire compared to the conventional one.

Air-conditioning cost savings, CO2 emission benefits and return on investment by using waste in porotherm bricks in hot-arid and warm-temperate climates

Building energy consumption has dramatically increased globally during the last few decades. This energy is primarily utilized to keep air-conditioned buildings at a comfortable temperature. As the worldwide demand for energy increases, net-zero or green buildings will undoubtedly become more and more crucial to address challenges related to climate change. It is well-known in this regard that the use of thermal insulation materials inside the building can contribute with temperature management and thermal comfort by preventing heat transmission. The present study examines the thermo-economic aspects of porotherm blocks filled with discarded insulations. Six different types of insulation were therefore investigated, and each was inserted into the porotherm brick cavities, including plastic powder, tire powder, cloth powder, leather powder, rockwool, and coconut pith. The effects of these newly developed brick configurations on air-conditioning costs, carbon dioxide emissions and payback time are compared to those of conventional porotherm blocks and burnt clay bricks. Thermo-physical properties of the aforementioned insulating materials, as well as porotherm brick and burnt clay brick, were established by experimental analysis. The thermo-economic analysis was carried out based on the number of degree-hours of heating and cooling to determine the building's annual energy usage. The thermo-economic performance of insulation-stuffed porotherm bricks was evaluated in two locations in India with distinct climatic characteristics: (28.57° N 75.12° E) New Delhi (warm-temperate climate) and (28.00° N 73.30° E) Bikaner (hot-arid climate). The rockwool porotherm brick wall demonstrated the best results in terms of lower unsteady transmittance, greater air conditioning cost-savings, appropriate payback spans, and improved yearly carbon mitigation values of 0.29 W/m2K, 0.83 $/m2, 0.95 years, and 15.65 kg/kWh, respectively, in hot-dry climates.

Energy efficiency of residential buildings in Tehran climate by saving energy

This paper examines and compares energy consumption in a sample building to reduce energy consumption and obtain the best performance in reducing energy consumption. Energy Plus software has done the modeling and simulation of energy consumption for a hypothetical five-story building in the climate of Tehran. The hypotheses used in this study include the use of four types of phase-change materials (PCMs) with different melting temperatures and specific latent temperatures in the Interior and exterior walls of the building, use of four different types of insulation, including glass wool (fiberglass), rock wool, elastomer and polyurethane in the outer walls of the building, the effect of the ratio of window area to exterior walls of the building on energy consumption, the use of various HVAC terminal systems including air conditioners, radiators and fan coils in the building. This study shows that, in general, the highest energy consumption with an increase of 71% compared to the reference building was related to the use of 90% of the area of the window to the external walls of the building, and the lowest energy consumption with a decrease of 20.81% compared to the reference building was related to the use of polyurethane thermal insulation.

Solar ponds-a mini review.

A solar pond is a simple system that collects and stores heat for thermal and electrical applications. Heat storage and heat extraction are the key factors in the solar pond. Salt is added to the pond with fresh water to form a salinity gradient solar pond (SGSP). The solar pond comprises of three zones, namely, the upper convective zone (UCZ), the non-convective zone (NCZ) and the lower convective zone (LCZ). The LCZ is also called the storage zone. Generally, the LCZ stores the heat energy of the incoming solar radiation, and this heat may be used for various applications. In this paper, a review is done on the study of solar ponds with various designs and modifications, heating methods, use of floating devices, use of baffle plates, use of heat exchangers, use of flat plate collectors, use of different types of insulation, etc.

Search for the optimal means for modelling the electric field of insulators

The article analyses software tools for simulation of electric field of insulators. The necessity of solving this problem is dictated by the fact that inaccuracy of simulation software allows stating that the simulation model cannot be improved correctly due to calculation errors in the program itself. Design features of different types of insulators, first of all, the most widespread and used - porcelain and glass insulators, are considered. The change of electric field in a glass and porcelain insulator operating in an AC network without contamination is described. Numerous calculation methods such as boundary element method, finite element method, integral equation method and others have been analysed. It is revealed, that from the point of view of functionality and expediency of application for solution of field problems relevant to electric power industry the finite difference method and finite element method are the most universal ones. The results of insulator electric field modelling using Ansoft Maxwell, CST EM Studio and Elcut software are given. Among Ansys, FEMLAB, Ansoft Maxwell, CST EM Studio, IES Coulomb and Elcut that were analyzed, the software Ansoft Maxwell and CST EM, where the finite element method is implemented, were chosen to solve the given problem. It was found out, which one of the software complies better with the given requirements as to accuracy (by calculation of error of deviation of mathematical modelling and experimental data) and in terms of the method incorporated in the algorithms of the software. Experimental data are compared with simulation results. The possibility of diagnosing insulators by electric field tension parameters has been revealed.

Thermal analysis of insulations used in the building shell with the optimization approach and reduction of energy consumption

Energy is one of the most important and basic needs in human life. Due to the high share of energy consumption in residential buildings, an important need to optimize energy consumption in this field is felt. In between, the role of building shell is very important, because it can play a pivotal role in this field and reduce energy consumption. In this research, initially different types of insulations used in various buildings were examined and classified. Determination of the physical and thermal characteristics of each material lead to the selection of the appropriate options. Finally, a simulation is performed using the EnergyPlus software to measure the efficiency of said materials in different roles. The work method is that first a building with all the standard specifications is designed in the software environment. The simulation is then done using the EnergyPlus software for different time periods and climate conditions in Tehran and the results are obtained. Moreover, by adding effective insulations to reduce energy consumption and re-simulation, the effect of each of them is analyzed. The results of this research show the reduction of energy consumption by up to 30%.

Improved U-Net based insulator image segmentation method based on attention mechanism

To realize the accurate identification and segmentation of the insulator string in the complex background image with diverse appearance and obscuration, this paper proposes an insulator segmentation method based on improved U-Net. The algorithm embeds the attention mechanism ECA-Net (Efficient Channel Attention Neural Networks) in the coding stage of U-Net to improve the model’s ability to extract semantic features, thereby improving the accuracy of insulator detection. Experimental results show that the average overlap IOU of the proposed method is 96.8%, which can more accurately segment different types of insulators in complex backgrounds.

Analysis of Methods of Protection of Inner Surface of Welds of Field Pipelines

In order to increase corrosion resistance, different types of insulation of the inner surface of pipes are used, but corrosion in this case often occurs on the inner surface of pipes in the zone of annular welded joints, where there is no insulation. There is no doubt that protection of the internal weld joint is an urgent task, the purpose of which is to increase the reliability of pipeline transport systems. There is a problem of insulation of the area of welded joints of pipes. In areas of welded joints of pipelines, effective corrosion protection shall be provided. A variety of methods have been used to protect internal coated welded joints from corrosion. Protective bushings are the most common method of protection of welded joints of field pipelines with internal coating.

Performance of the hygrothermal behavior of the CLT wall using different types of insulation; XPS, PF board and glass wool

The physical input values of buildings were entered into a thermal moisture simulation software called WUFI. The categorized criteria were variables of insulation type, standards of insulation (U-value), climate, and the presence or absence of vapor permeable inside and outside the wall. The simulation results graphically displayed the moisture content of the entire wall and the potential for mold growth. The results showed that a vapor barrier paper needs to be installed inside the wall to produce less mold and that the wool-type insulation materials have more moisture content than that of polyester insulation materials. Next, the actual experiment was conducted in a Facing thermo-hygrostat for evaluating the performance of the hygrothermal behavior of the CLT wall using different types of insulation, namely, XPS, PF board, and glass wool. The direction and amount of water vapor in the wall owing to temperature changes were observed in the external environment. The experimental results showed that the CLT wall containing the glass wool insulation was vulnerable to heat and humidity, whereas the CLT wall containing the PF insulation was excellent in resisting heat and humidity. Finally, CLT building with the previously studied was implemented. In this process, a life cycle cost analysis was performed by calculating the daily heating and cooling values for domestic climates to determine the optimal thickness of the insulation to used for each CLT wall.

Current State and Prospects of Development of Gas-Insulated Power-Transmission Lines and Busbars at 110–1100 kV

Issues related to the development and technical operation of gas-insulated lines are considered. A comparison of the technical parameters of lines with different types of insulation is performed. The throughput of and losses in power-transmission lines of different types are identified; the specific electric capacity and technical losses in the gas-insulated lines are determined, and their safety and environmental friendliness are evaluated. The assessment of gas-insulated line construction variants and dependence of their real dimensions on the nominal voltage is carried out. Options for using different gases in gas-insulated lines are considered. The comparison of the intensity of magnetic fields of overhead, cable, and gas-insulated power lines showing the efficiency of the gas-insulated line application is performed.

Microcontroller Device for Conductor Identification Using Acoustic Signal

When repairing and replacing electrical wiring in enterprises, the main difficulty is the lack or poor quality of documentation, plans for conductors laying. Distinguishing wires (cables) and their cores by the color of the shells or using tags attached to the ends is difficult if the shells have the same color and there are no tags. Devices and technical solutions used to identify wires and cables do not allow recognizing conductors without breaking the electrical circuit, removing insulation, and de-energizing the network. Searching for the right conductor is a time-consuming operation. (Research purpose) The research purpose is developing a new microcontroller device for identifying wires using an acoustic signal. (Materials and methods) Literature sources has been searched for devices for conductors identifying. (Results and discussion) The article proposes a method that involves feeding an acoustic signal to a wire at one point and capturing it at another, in order to recognize the desired wire. The article presents results of comparison of the developed microcontroller device for identifying conductors using an acoustic signal with known devices and methods for conductors recognizing. (Conclusions) The article reveals the shortcomings of existing methods and means of identifying wires and cables. Authors performed a theoretical calculation of the sound pressure in the conductor at a given distance. The article presents the calculation of speed of acoustic waves in conductors with different types of insulation. Authors designed a microcontroller device for identifying conductors using an acoustic signal and tested it. It was determined that the device increases the safety of work, reduces the cost of operating internal wiring and identification time; eliminates the violation of wire insulation, the need to disable electrical receivers. The convergence of theoretical calculations and experimental data was shown.

Application of Polarization and Depolarization Current in High Voltage Insulator - A Review

Deterioration of cable insulator can be caused by many factors such as aging, fault and breakdown. These factors are caused by the presence of moisture, impurities and heat due to high temperatures in an insulator. The maintenance and replacement for insulation system in power cables, power transformers and electric machine stator are generally expensive and time consuming. Thus, the performance and ability of an insulator can be monitored through polarization and depolarization current (PDC). Polarization and depolarization current (PDC) is a non- destructive test method that is used to analyse many factors that affects the behaviour of an insulator in time domain. This paper presents the review on application of polarization and depolarization current test method on different type of insulator. The factors that affects the performance of different type of insulator will be discussed in this paper. Moreover, the theory of polarization and depolarization current will be explained in order to understand the behaviour of polarization and depolarization current curve when fault occurs. Last but not least, this paper will provide a review on the different type of factors that affects the performance of different types of insulation.

Comparison on space charge and voltage distribution of high voltage insulator subjected to different contamination levels

This paper presents the study of space charge distribution on high voltage (HV) insulators under different levels of contamination. Two types of HV insulators were used in this work particularly glass and porcelain insulators. A string of 4-unit glass and porcelain insulators with 33 kV of lines voltage was designed and simulated using QuickfieldTM software. Four levels of contamination layer with different thickness have been applied on the surface of insulators to observe the effect of space charge distribution. Simulation results show that different types of insulators used at transmission lines give different effects on charge and voltage distribution. It is also found that the amplitude of charge for a single porcelain insulator is much higher compared to a single glass insulator. Similarly for a string of 4-unit insulators, the voltage distribution along the creepage distance of porcelain insulators is much higher compared to glass insulators under all contamination levels.

Experimental investigation of the aerodynamic drag of roof-mounted insulators for trains

This paper presents the results of experimental investigations on the aerodynamic drag of roof-mounted insulators for use on low- and high-speed trains. Wind tunnel investigations at different Reynolds numbers in the subcritical, critical, and supercritical flow regime were performed, in addition to investigations using wall-mounted cylinders. Furthermore, the impact of insulator sheds made of flexible material was analyzed. For a better understanding of the aerodynamic behavior of the insulators when mounted on trains, different boundary conditions representing realistic configurations as found on the roof of trains were simulated. From the measured drag, the energy demand to overcome the aerodynamic resistance of different types of insulators was calculated. Depending on the above mentioned boundary conditions, a noticeable contribution of the insulators to the entire train's aerodynamic drag could be observed. With flexible insulator sheds, a further increased air resistance was observed with the onset of fluttering. Similar to the cylinder, the aerodynamic behavior of the insulators depends on the respective Reynolds number.

Influence of pollution chemical components on AC flashover performance of various types of insulators

The pollution on insulators is composed of various chemical components, which threaten the stability of external insulation. However, the existing insulation designs have not taken this issue into consideration. This work aimed to study the influence of pollution chemical components on flashover performance of insulators with various materials. Flashover tests of porcelain, glass and silicone rubber insulators polluted by eight types of common contaminants were conducted. Based on the test data, the influence of chemical components and their solubility on equivalent salt deposit density (ESDD) and insulator flashover performance were analysed; and the electrical properties of different types of insulators were compared. Results show that the ESDD contribution rate changes with chemical components. The dissolution characteristic has a significant influence on the measurement of ESDD; slightly soluble contaminants need to be considered separately. The corresponding insulator flashover gradient for ions can be summarised as Cl− < NO3 − < SO4 2−, K+ < Na+, NH4 + < Ca2+. For a glass insulator, the flashover gradient is 4.9–17.0% higher than that of a porcelain insulator. For a silicone rubber insulator, this gap reaches 14.6–24.4 and 83.3–90% for freely soluble pollution and CaSO4, respectively, this phenomenon can be explained by the combined action of the slightly soluble character of CaSO4 and hydrophobicity transference of silicone rubber.