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This paper aims to present simulation studies on voltage and electric field characteristics for imperfect ceramic insulators using QuickField^TM software. Based on previous studies, it is accepted that string insulator can still serve the transmission line although imperfect of certain insulator exist in a string. However, different materials of porcelain and glass type had made these insulators own different abilities to carry electricity to be transferred to the consumers.

Cap and pin type of porcelain and glass insulators are used as the main subject for comparison. The simulation works begins with modeling a single insulator, followed by string of ten insulators with their respective applied voltage, that is, 11 and 132 kV. The insulator was modeled in alternate current conduction analysis problem type using QuickField Professional Software. Technical parameters for porcelain and glass insulator were manually inserted in the modeling.

This paper presents an investigation on the influence of broken porcelain and glass insulators in string for voltage and electric field characteristics. For single insulator, the voltage distribution may literally reduce when experiencing external damages; whereby the broken porcelain insulator condition is worse than the glass insulator. In terms of electric field distribution, the glass insulator is badly affected compared with the porcelain insulator, as it is pulverized comprehensively.

Further work needs to be done to establish whether the experiments of these simulations study will present coequal outcomes. This study endeavors in promoting a good example of voltage and electric field characteristics across high voltage (HV) insulator with the presence of broken insulator in the string.

This study is beneficial to future researchers and manufacturing companies in strategic management and research planning when they involve in the field of HV insulators. It will also serve as a future reference for academic and study purposes. This research will also educate many people on how HV insulators work.

This study will be helpful to the industry and business practitioners in training for the additional results and knowledge to be updated in the area of HV insulators.

This paper presents the analysis of porcelain and glass insulators according to their respective logic conditions when broken. Consequently, the existence of a damage insulator in a string may alter the distribution of voltage and electric field which may ultimately lead to the insulation breakdown after some time. This is because the broken insulator may cause other insulators to withstand the remaining voltage allocated for that particular insulator and may affect the insulators in terms of the life span. Therefore, the distribution of voltage and electrical field characteristics in the presence of broken insulators had been studied in this project.

This paper, a case study, aims to illustrate the application of Six Sigma in a small-scale ceramic manufacturing industry. The purpose of this paper is to demonstrate the empirical application of DMAIC methodology to reduce failure rate at high voltage (HV) testing of one of the most critical products, insulator.

The case study is based on primary data collected from a real-life situation prevailing in the industry. The case study methodology adopted here is at one small-scale unit wherein the authors have applied DMAIC methodology and observed and recorded the improvement results, especially, reduction in failure rate at HV testing of insulator and, thus, increase in Sigma level.

The results found after implementation of the solutions are very significant. The rejection percentage has been reduced from 0.5 to 0.1 percent and consequently the Sigma level has been improved from 4.4 to 5.0.

This success story can be a guiding roadmap for other such industries to successfully implement Six Sigma to improve quality, productivity and profitability.

This case study will serve as one of the resource bases for the industries which have till not implemented Six Sigma and benefited from the same.

Improved quality and productivity leads to better economy. This case will help industries to serve the society with better economy with improved quality and productivity.

Though ceramic industries in India are having enormous potential for growth, majority of them, especially, small and medium industries are either not aware of or not implementing Six Sigma to reap its multidimensional benefits of improving quality, productivity and profitability. This study highlights the benefits reaped by small-scale ceramic manufacturing industry opening up the avenues for its application at other such organizations.

In the paper, some cases of using HV insulator in SF6 gas medium are discussed. Computations, permitting to optimize the insulation system geometry and to make use of the HV insulator in atypical constructions, were carried out. The equipotential lines and diagrams of the electric field strength, enabling to draw conclusions concerning shapes of constructions are presented.

The aim of the paper is to present the results of investigations of fine particle generation by small biomass combustion and the possibility of reducing the emissions by electrostatic precipitation.

The grains, wood‐logs, wood‐, mixed‐ and straw‐pellets were combusted in two stoves and two boilers. The set‐ups were operated according to DIN‐4702. Particle number concentration in the gas flow was measured by Scanning Mobility Particle Sizer and particle mass concentration was measured according to the Guidelines VDI‐2066 upstream and downstream a novel space charge electrostatic precipitator (ESP). The ESP consists of an ioniser and a grounded brush inside of a tube form grounded collector electrode.

The ESP ensures stable operation at gas temperatures up to 350°C. The use of sharp‐points high voltage electrode ensures effective particle charging at high particle number concentrations. The combustion of wood‐pellets is characterized by lower particle mass concentrations. The highest particle mass concentrations were observed by the straw‐pellets combustion. The ESP ensures particle collection with mass collection efficiency 87±3% for wood‐logs and 82±2% for wood‐pellets combustion.

The novel ESP is recommended for exhaust gas cleaning from small scale biomass combustion facilities and domestic heating units. The use of the ESP would reduce the emissions of fine aerosol into the atmosphere and improve the air quality.

The paper presents the comparative analysis of particle size distribution and particle mass concentrations in the exhaust gas from small‐scale combustion units for different types of biomass. The study confirms the possibility to reduce particle emissions by electrostatic precipitation. The originality of the technology and apparatus is patently protected.

The paper first discusses the question of which objectives may be meaningful for the optimization of high‐voltage insulators, and exhaustively analyses the relationship between field strength and the geometrical properties of the boundary surfaces of a Boundary Value Problem (BVP). Afterwards a theoretical formulation of the optimization task is presented. In order to seek the parameters that may play a role in the optimization task, a formula for the global field derivative for shaping boundaries is derived. The parameters which can be determined by means of the numerical field calculation are discussed. These can be used as a point of reference for the development of an optimization procedure.

The ionization of the air surrounding the phase conductor in high-voltage transmission lines results in a phenomenon known as the Corona effect. To avoid this, Corona rings are used to dampen the electric field imposed on the insulator. The purpose of this study is to present a fast and intelligent surrogate model for determination of the electric field imposed on the surface of a 120 kV composite insulator, in presence of the Corona ring.

Usually, the structural design parameters of the Corona ring are selected through an optimization procedure combined with some numerical simulations such as finite element method (FEM). These methods are slow and computationally expensive and thus, extremely reducing the speed of optimization problems. In this paper, a novel surrogate model was proposed that could calculate the maximum electric field imposed on a ceramic insulator in a 120 kV line. The surrogate model was created based on the different scenarios of height, radius and inner radius of the Corona ring, as the inputs of the model, while the maximum electric field on the body of the insulator was considered as the output.

The proposed model was based on artificial intelligence techniques that have high accuracy and low computational time. Three methods were used here to develop the AI-based surrogate model, namely, Cascade forward neural network (CFNN), support vector regression and K-nearest neighbors regression. The results indicated that the CFNN has the highest accuracy among these methods with 99.81% R-squared and only 0.045468 root mean squared error while the testing time is less than 10 ms.

To the best of the authors’ knowledge, for the first time, a surrogate method is proposed for the prediction of the maximum electric field imposed on the high voltage insulators in the presence Corona ring which is faster than any conventional finite element method.

The purpose of this paper is to propose an improved charge simulation method (CSM) based on the real‐coded genetic algorithm (GA), in which the tedious testing and adjusting work in the traditional CSM is avoided. In addition, less simulation charges are used in the simulation model for the same object compared with the traditional CSM.

In the improved CSM, the information of testing points are combined with the matching points, hence the size and locations of simulation charges can be only computed by the information of matching points, and the testing calculation in the traditional CSM is avoided. According to the Maxwell equations, an overdetermined equation is reformulated, and an improved GA is used to solve it. The process to create the initial population is improved, boundary condition information of part matching points and human experience are added into the initial population, which enhanced the convergence rate of the search calculation.

Combining the information of testing points into that of the matching points in the improved CSM, the tedious testing calculation can be avoided, and the GA is effective to solve the overdetermined equation for the improved CSM. By importing the information of part matching points and human experience, the search process can be accelerated and the convergence of the method is ensured. Comparison between the efficiency of traditional CSM and the improved CSM is presented, less simulation charges are used compared with the traditional CSM for the same object.

The improved CSM cannot adjust the count of simulation charges in the equivalent model automatically.

Calculations of a sphere‐plane electrode model and a 64 kV insulator string are carried out to verify the validity of the improved CSM. In addition, it can also be used to compute the power frequency electric field of HV transmission apparatuses.

By improving the process of the traditional CSM and importing the GA, an improved CSM for the calculation of power frequency electric fields produced by high‐voltage apparatuses is presented in the paper, which can avoid the tedious testing and adjusting work in the traditional CSM.

The purpose of this paper is to introduce an efficient model for analysis of the voltage distribution along the long ceramic insulator strings in a high‐voltage tower window, especially when the structure and parameters of the ceramic insulator are unknown. The effect of the grading ring on the voltage distribution is also investigated.

A circuit model composed of capacitors is used to analyze the voltage distribution along the ceramic insulator strings in a transmission tower window. The capacitances of the disk insulators, line conductors, and tower are obtained by using the finite element method, charge simulation method, boundary element method, and measurement according to their characteristics.

The model is very efficient. The voltage distribution along insulator strings can be optimized by adjusting the parameters of the grading ring. The maximum amount of voltage applied to a single insulator disk can be reduced effectively by increasing either the diameter of the grading ring or the distance from the upper surface of the grading ring to the high‐voltage end of the insulator string.

The model is very efficient for analysis of the voltage distribution along the long ceramic insulator strings, especially when the structure and parameters of the ceramic insulator are unknown.

A hybrid formulation is proposed that incorporates finite element substructuring and Galerkin boundary elements in the numerical solution of Poisson's or Laplace's equation with open boundaries. Substructuring the problem can dramatically decreases the size of matrix to be solved. It is shown that the boundary integration that results from application of Green's first theorem to the weighted residual statement can be used to advantage by imposing potential and flux continuity through the contour which separates the interior and exterior regions. In fact, the boundary integration is of exactly the same form as that found in Galerkin boundary elements.

The purpose of this paper is to propose a new approach for designing different parts of a high voltage bushing. It also aims to consider technical and economical criteria for the optimum solution of the design problem.

A novel method for finding the optimal contours of different elements of high voltage bushings, including ceramic insulator, electrode, and flange angle is presented. The rational Bézier curves are used for defining the surface of the insulators and conductors of the equipment. Then, these curves are optimally adjusted to obtain an appropriate techno‐economical solution. The utilized optimization method is the improved bacterial foraging algorithm (BFA) with variable step sizes. In the design procedure, two‐dimensional finite element method (2D FEM) is used to calculate the performance parameters in each step of the design procedure. In order to evaluate the performance of the proposed algorithm, optimal design of different elements of a 110 kV bushing using BFA and genetic algorithm is presented, compared, and discussed as well.

The results of this research show that the technical design criteria and economical costs are satisfied by the proposed method. It is concluded that the rational Bézier curves can be implemented for other similar applications and optimal design of other equipment in the electrical engineering field combined with heuristic optimization techniques.

Bezier curves are used for the first time for bushing design purpose. Two heuristic techniques are also implemented in order to facilitate the comparison and avoid local solutions.