Partial discharges (according to IEC standard 60270) are harmful electrical discharges in electrical systems.
The early detection of these anomalies, as well as the identification of the exact location of the emission, will help to carry out corrective actions on time and with high efficiency. These discharges release energy from time to time, creating a distinctive acoustic signature that can be captured by an ultrasound listening device (ULD).
According to current statistics, 85% of power failures occur in medium and high voltage transformers. Partial discharges such as the corona effect are the main causes of power loss and damage to electrical equipment insulation, hence the need to have an inspection tool for these discharges at hand. This is more so the case in acoustic inspection, where there is often no temperature increase in corona discharges.
UL101 APPLICATIONS FOR PARTIAL DISCHARGE DETECTION
Corona - High energy electrical discharge
Cause: the ionization of the surrounding air due to the escape of free electrons from our circuits
Damage: mechanical, electrical, and thermal
Cost: loss of expensive power management components
Tracking/Electrical Treeing - First stage of electrical arcing
Cause: excessive electrical field stress within small regions of the dielectric
Damage: reduced insulation and the ability to leak current from the conductor
Electric Arcing - Short circuiting and flame-like discharge
Cause: two electrodes subjected to a potential differential and placed within a rarefied gaseous atmosphere
Damage: security risk and imminent failure