Ofil’s proprietary material Cannot be used without Ofil's explicit permission
Ofil’s proprietary Material | 2011 Partial Discharge and the Corona Phenomenon Solar Blind Imaging Corona Inspection as a PDM tool in hand Faults Indications Methodology
Ofil’s proprietary Material | 2011 Detect PD corona & arcing - in daylight Diagnostic tool Condition monitoring of critical components Perform predictive maintenance
Trigger localized high e-fields that exceed a critical value kV/cm Generates Audio noise Corrosive materials (O 3, NO - ) Radio and TV interferences UV - corona
E field e e + e e + e e e + -V e UV Ph In the presence of a strong E-field Free electrons accelerate Collide with air molecules and ionize them Additional electrons are released Photons are released with recombination Procedure repeats itself
Ozone blocks Solar UV Signals
Goal: Collect UV events & superimpose Imaging “Black Box” input - sceneryoutput - screen
Ofil’s proprietary material Cannot be used without Ofil's explicit permission
External – surface Line of sight Voltage dependent Any weather conditions Indicator & Actor Fault early stage detection
Corrosion and erosion Pitted cement Hydrophobicity compromise RFI/TVI
3. Lineman from EMC takes down the faulty arrestor 1. Corona during hazy day 2. Camera depicts the exact corona arcing location RFI/TVI Case 1: A US Government Licensed Radio Amateur Operator: The receiving equipment was reading a noise level of some 30 dB over S9 (Signal strength is measured in S-units from S1 to S9) and the noise blanking system of the receiving equipment could not eliminate the noise.
Case 2: USA 1.RFI at FAA Control Tower during wet weather 2. The source: Bad grounding on 4.16kV, 12.47kV, 115kV insulators Case 3: Czech Republic 1.RFI at Czech Radio Telecomm Authority experienced TVI 2. The source: Pin of a ceramic insulator was wrongly installed
Tracking & loss of hydrophobicity
Brittle fracture: corona cameras can clearly show surface discharge that exists on insulators with housing imperfections in order to avoid catastrophic failure.
Faulty designs Faulty installations Poor material Existing processes
No corona ring Grading ring installed backwards
Cracked insulator Wrong design
AN, RI, TVI concern? Events per Minute Can it be damaged by corona? Corona- where? Critical component? Material type Critical location? Corona intensity? No Yes High> <Medium<5000 Low<1000 Monitor for additional signs Schedule repair or replacement Repair or replace ASAP No Yes Repair or replace ASAP
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