Corona Discharge

Detect and analyze electrical anomalies with unparalleled clarity.

What is Corona Discharge?

Corona discharge is the luminous partial discharge of conductors and insulators due to air ionization, occurring when the electric field surpasses a critical threshold.

The intense local electric field ionizes the surrounding air, resulting in a discharge. This process is accompanied by the excitation of nitrogen molecules, leading to the emission of UV radiation. The accumulation of ionization only takes place when the electron moves sufficiently quickly, that is, when the electric field exceeds its critical value.

Thus, a component generating a localized high electric field, due to a defect or fault, will exhibit corona activity. Some molecules are not ionized but are excited – and upon relaxation, they emit photons.

Corona creates corrosive substances: ozone and nitrogen oxides, which in the presence of water vapor, form nitric acid. Utility companies are often alerted to the presence of corona through complaints about faulty radio or television signals. Since corona is invisible to the human eye in daylight, maintenance personnel employ tools such as corona cameras or radio antennas, targeting suspicious areas to track and monitor the corona activity.

Detrimental Effects of Corona Discharges

Corona Concerns

Corona discharges pose various detrimental and environmentally disruptive effects.

  • Corrosive Production: Generation of corrosive substances, such as ozone and nitrogen oxides, which form nitric acid under high humidity conditions. These corrosive elements can reduce the lifespan of high-voltage lines and substation components.
  • Impact on Insulators: Corona causes damage to HV insulators, particularly non-ceramic insulators (NCIs).
  • Radio Interference: Primarily affecting AM transmissions, this radio interference (RI/RFI) can be a notable concern.
  • Audible Noise: The noise caused by corona might result in complaints from customers.
  • Thermal Limitations: Corona produces minimal heat, which means it remains undetectable by thermal cameras.
  • Preventative Maintenance and Reduced Downtime: Our technology empowers you to detect electrical system faults early, preventing costly equipment damage and minimizing disruptive downtime. This allows for proactive maintenance and ensures your systems operate smoothly and efficiently.
  • Enhanced Safety and Peace of Mind: By identifying potential problems before they escalate, this technology contributes to a safer working environment. This proactive approach minimizes the risk of accidents and fosters peace of mind.
  • Optimized Power Transmission and Reduced Costs: The technology helps you maintain the integrity of insulators and other electrical components, minimizing energy loss and boosting the reliability of your power transmission system. This translates to reduced operational costs and a more efficient electrical infrastructure.

Diverse Corona & Arcing Detection Systems

Integrators can now enhance their testing toolkit with UV detection functionalities and advance their current inspection systems with PD visualization sensors.

Ofil presents two variants of dual-spectrum UV-Visible block cameras, suitable for integration into fast-moving motorized setups like trains, vehicles, and off-roaders, or for use as fixed monitoring tools.

DayCor® primary cameras introduce the UV layer, shedding light on concealed issues for those assessing the state of facilities and structures. The information gathered through DayCor® is both thorough and robust. This is the reason Ofil’s cameras have the moniker “UV Eyes” – they extend the normal visual spectrum of humans to encompass UV light.

Advanced Inspection Tools

Explore the innovative range of aerial inspection instruments from our partner, OFIL Systems, each designed to elevate the precision and efficiency of your surveillance operations.

The DayCor® micROM HD is a cutting-edge corona camera tailored for UAV deployment. Featuring both UV & Visible dual sensors, it’s adept at daylight corona detection and imaging. Its compact, lightweight design, combined with electromagnetic shielding and efficient energy management, allows for longer, agile UAV flights, ideal for inspecting power lines.

The camera not only streams & records in HD – ensuring clear, detailed visuals of equipment for maintenance referencing – but also offers real-time corona discharge representation. This clarity aids in promptly pinpointing and assessing the severity of faults. Optional integration solutions available.

LuminarHD is a premium handheld corona camera tailored for indoor and outdoor electrical inspections. Powered by Ofil’s DayCor® technology, it ensures unmatched sensitivity to UV radiation, capturing precise images of corona discharges. Its ergonomic design is complemented by features like a Sun Readable LCD and a potent LED flashlight.

Integrated GPS and environment sensors provide accurate, location-specific data, all displayed in real-time on a crisp screen. With LuminarHD, gain swift insights into electrical anomalies and overall asset condition.

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