Study of kinetic behavior of silicone rubber used on the cover of polymeric insulators

There is a vital need to understand the flashover process of polymeric insulators for safe and reliable power system operation. This paper provides a rigorous investigation of forecasting the flashover parameters of High Temperature Vulcanized (HTV) silicone rubber based on environmental and polluted conditions using machine learning. The modified solid layer method based on the IEC 60507 standard was utilised to prepare samples in the laboratory. The effect of various factors including Equivalent Salt Deposit Density (ESDD), Non-soluble Salt Deposit Density (NSDD), relative humidity and ambient temperature, were investigated on arc inception voltage, flashover voltage and surface resistance. The experimental results were utilised to engineer a machine learning based intelligent system for predicting the aforementioned flashover parameters. A number of machine learning algorithms such as Artificial Neural Network (ANN), Polynomial Support Vector Machine (PSVM), Gaussian SVM (GSVM), Decision Tree (DT) and Least-Squares Boosting Ensemble (LSBE) were explored in forecasting of the flashover parameters. The prediction accuracy of the model was validated with a number of error cost functions, such as Root Mean Squared Error (RMSE), Normalized RMSE (NRMSE), Mean Absolute Percentage Error (MAPE) and R. For improved prediction accuracy, bootstrapping was used to increase the sample space. The proposed PSVM technique demonstrated the best performance accuracy compared to other machine learning models. The presented machine learning model provides promising results and demonstrates highly accurate prediction of the arc inception voltage, flashover voltage and surface resistance of silicone rubber insulators in various contaminated and humid conditions.

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Experimental Study on Optimization of Filler Concentration of Silicon Rubber Compound Used in High Voltage Insulators

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.39282 ◽

2021 ◽

Vol 9 (12) ◽

pp. 327-346

Author(s):

Allu Shanmukha Rao

Keyword(s):

Tensile Strength ◽

Specific Gravity ◽

Polymeric Material ◽

Silicone Rubber ◽

Power Transmission ◽

Dielectric Strength ◽

Filler Material ◽

Inclined Plane ◽

Tear Strength ◽

Polymeric Insulators

Abstract: In any power transmission system, insulators are essential for a reliable electrical power supply. The Efficiency of insulators will be decided by their electrical and mechanical properties. Recently in many of the power transmission systems, the conventional porcelain insulators are being replaced by polymeric insulators due to various advantages in their properties. Polymeric insulators have been increasingly popular in recent years as a result of their superior performance in contaminated environments due to their hydrophobic nature. However, research is still being carried out on Polymeric material with regards to ageing condition and feasibility for large scale utilization. Ageing of insulation is due to Environmental, Tracking and Erosion conditions. Ageing leads to immature failures and uncertainty in the performance of the insulators. The constituent materials and their properties have a significant impact on the performance of polymeric insulators. There is a strong need to look into newer filler materials which can be added to the existing polymeric base materials to constitute a composite. Keeping this in mind, in the proposed research uses Silicone rubber as base polymeric material and along with that additives are added to arrive at three different composites. A new filler material will be added to the base material forming a new composite. All these HTV Silicone rubber based composites are then tested the recovery of hydrophobicity, dielectric strength, hardness, specific gravity, tensile strength , ultimate elongation ,tear strength properties based on ASTM standards. Further, Inclined plane Tracking and Erosion studies are also conducted on the polymeric test samples for 6 hours to evaluate the SiR housing material suitability for outdoor insulator applications by subjecting them to AC high voltages under laboratory conditions as per IEC 60587 standards. Keywords: Recovery of hydrophobicity, dielectric strength, hardness, specific gravity, tensile strength, ultimate elongation, tear strength, inclined plane tracking and erosion, ageing, filler material.

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Computing cell tractions from particle displacements on silicone rubber substrata

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168542 ◽

1994 ◽

Vol 52 ◽

pp. 162-163

Author(s):

Tim Oliver ◽

Akira Ishihara ◽

Ken Jacobsen ◽

Micah Dembo

Keyword(s):

Plane Stress ◽

Linear Elasticity ◽

Silicone Rubber ◽

Mathematical Analysis ◽

Elastic Recovery ◽

Video Images ◽

Cell Traction Forces ◽

Latex Beads ◽

Cell Traction ◽

Better Than

In order to better understand the distribution of cell traction forces generated by rapidly locomoting cells, we have applied a mathematical analysis to our modified silicone rubber traction assay, based on the plane stress Green’s function of linear elasticity. To achieve this, we made crosslinked silicone rubber films into which we incorporated many more latex beads than previously possible (Figs. 1 and 6), using a modified airbrush. These films could be deformed by fish keratocytes, were virtually drift-free, and showed better than a 90% elastic recovery to micromanipulation (data not shown). Video images of cells locomoting on these films were recorded. From a pair of images representing the undisturbed and stressed states of the film, we recorded the cell’s outline and the associated displacements of bead centroids using Image-1 (Fig. 1). Next, using our own software, a mesh of quadrilaterals was plotted (Fig. 2) to represent the cell outline and to superimpose on the outline a traction density distribution. The net displacement of each bead in the film was calculated from centroid data and displayed with the mesh outline (Fig. 3).

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Video-microscopic measurement of cell-substratum traction forces generated by locomoting keratocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146783 ◽

1993 ◽

Vol 51 ◽

pp. 188-189

Author(s):

Tim Oliver ◽

Michelle Leonard ◽

Juliet Lee ◽

Akira Ishihara ◽

Ken Jacobson

Keyword(s):

Silicone Rubber ◽

Molecular Motors ◽

Video Frame ◽

Traction Forces ◽

Cell Traction Forces ◽

Latex Beads ◽

Cell Traction ◽

Local Cell ◽

Microscopic Measurement ◽

Kinetics Of

We are using video-enhanced light microscopy to investigate the pattern and magnitude of forces that fish keratocytes exert on flexible silicone rubber substrata. Our goal is a clearer understanding of the way molecular motors acting through the cytoskeleton co-ordinate their efforts into locomotion at cell velocities up to 1 μm/sec. Cell traction forces were previously observed as wrinkles(Fig.l) in strong silicone rubber films by Harris.(l) These forces are now measureable by two independant means.In the first of these assays, weakly crosslinked films are made, into which latex beads have been embedded.(Fig.2) These films report local cell-mediated traction forces as bead displacements in the plane of the film(Fig.3), which recover when the applied force is released. Calibrated flexible glass microneedles are then used to reproduce the translation of individual beads. We estimate the force required to distort these films to be 0.5 mdyne/μm of bead movement. Video-frame analysis of bead trajectories is providing data on the relative localisation, dissipation and kinetics of traction forces.

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