One of the phenomena associated with all energized electrical devices, including high-voltage transmission lines, is corona. The localized electric field near a conductor can be sufficiently concentrated to ionize air close to the conductors. This can result in a partial discharge of electrical energy called a corona discharge.

Corona Ti thermal Imaging

What is Corona?

– It is a phenomenon associated with all transmission lines. Under certain conditions, the localized electric field near energized components and conductors can produce a tiny electric discharge or corona that causes the surrounding air molecules to ionize, or undergo a slight localized change of electric charge.

– Corona occurs on all types of transmission lines, but it becomes more noticeable at higher voltages (345 kV and higher).

What’s The Fuss?

– Corona from conductors and hardware may cause audible noise and radio noise

– Audible noise from conductors may violate noise standards

– Radio noise from conductors may interfere with communications or navigation

– Loss may be significant when compared with resistive loss of conductors

– Can cause possible damage to polymeric insulators


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Corona Ti thermal imaging inspection