Supply & Application of HVIC by Epsilon Asia Group: 08 to 11 May 2012

Application of Epsilon Midsun 570 Gen-4 RTV

HVIC (High Voltage Insulator Coating)

At

Extremely Polluted 132kV Switchyard

Epsilon: Key Partners in India

• Epsilon an engineering company and is

exclusive national partners with:

• Dongfang India for Minimal-Oil Boiler

Combustion Systems

• Dongfang-Hitachi VFDs, PV Inverters

• SYCG/Nexans XLPE Cable

• Epsilon Midsun HVIC & Silicones

132kV Switchyard Overview

• Insulators prone to severe contamination

• Leakage Current & Corona observed

• Various conventional methods to avoid flashovers tried

• Unplanned outages caused production losses

• Customer has a strong commitment to safety & environment

• A safe & effective solution was required

132kV Switchyard Prone to contamination due to surroundings and industry type

Targets:

Mitigate Risks of Leakage Current

Reduce the need for Insulator Washing

Mitigate Risks of Flashovers

HVIC of Choice:

Epsilon Midsun 570 Gen-4 RTV Ultra-Hydrophobic RTV High Voltage Insulator Coating (HVIC)

Conductive Tracking Path Cannot be Formed (All drops of water are discrete)

IEEE Evaluation of RTV Coating in Coastal Conditions

• IEEE Evaluation of RTV Coating for Station Insulators subjected to Coastal Pollution – H.M Schneider, Senior Member, EPRI High Voltage Research

Centre)

•Performance of Breaker Support Insulators (BSIs) tested before and after application of RTV Coating •Resistance to Flashovers tested in field tests to check for additional equivalent creepage imparted by the coating

… The results

Measurements are given in ESDD as: Quantity of NaCl per unit area (mg/cm2) Test Reports showed ESDD as high as 0.034 mg/cm2 several months after wind storms, natural and manual washing •Uncoated BSIs flashed over at 209kV •RTV coated BSIs flashed over at 300kV Improvement of performance of:

43.5% withstand voltage

Hydrophobicity Recovery

Hydrophobicity Tested (CPRI Labs)

Hydrophobicity Classification (HC level as per STRI)

Virgin Sample HC 1

After 100-hours continuous exposure to Corona

HC 6

Epsilon Midsun Hydrophobicity Recovery within 48 hours of Corona Destruction

HC2

•It is essential for the silicone material to recover its hydrophobicity for long-term effective performance

•Epsilon HVIC Test Results of Hydrophobicity recovery at CPRI

Hydrophobicity (Water-Repellency) Classification

Hydrophobicity Classification (HC) goes from HC1 to HC7 HC1: Completely Hydrophobic HC7: Completely Hydrophilic

Typical Examples from HC1 to HC6

HC Description

HC1 Only discrete droplets formed. θr≈80° (or larger) for majority of droplets

HC2 Only discrete droplets formed. 50°<θr< 80° for the majority of droplets.

HC3 Only discrete droplets formed. 20°< θr<50° for majority of droplets. Usually they are no longer circular

HC6 Wetted areas cover > 90% small un-wetted areas still observed

HC7 Continuous water film

Application Procedure

Contaminated Insulator Surfaces

Step 1: Remove Loose Contaminant

Step 2: Gently Scrape Oily Deposits

Step 3: Warm Soap Spray Cleaning

Step 4: Solvent Wipe

Step 5: Agitate Epsilon Midsun HVIC

Step 6: Application of Epsilon HVIC

Spray Application

Step 7:Coating Thickness Measurement

Checking Coating Thickness (WFT)

Post-Application Switchyard Clearing

Touch up + Removal of Protective Sheets

Coated Insulators

Epsilon HVIC

Team

Safety Training +

Documentation

07 May 2012

Scheduled Start:

08 May 2012

Actual Start:

08 May 2012

Scheduled End:

11 May 2012

Actual End:

11 May 2012

Thank you

Epsilon Asia Group X29 Hauz Khas, New Delhi, India

Level 29, Offices at CentralWorld, Bangkok, Thailand +91. 11. 4101.4888; www.epsilonasia.com