The Importance of Partial Discharge Monitoring in High-Voltage Systems

Partial discharge (PD) is one of the most critical indicators of insulation failure in high-voltage systems.
Left undetected, PD can lead to unexpected outages, equipment damage, and safety hazards.

Understanding and monitoring PD activity is essential for modern power systems.

What Is Partial Discharge?

Partial discharge is a localized electrical discharge that occurs within insulation or at interfaces under high voltage stress.
Although small, repeated PD events gradually degrade insulation, leading to eventual breakdown.

Common PD sources include:

• Voids in insulation

• Surface contamination

• Poor cable joints

• Aging switchgear components

Why PD Is a Silent Threat

PD activity often:

• Occurs without visible symptoms

• Does not immediately trigger protection systems

• Accelerates over time

By the time a failure occurs, damage is often extensive and costly.

Modern PD Detection Techniques

Advanced PD detectors use multiple sensing technologies:

• UHF (Ultra High Frequency) detection

• TEV (Transient Earth Voltage) measurements

• Ultrasonic sensors for surface discharge

These methods allow online, non-intrusive diagnostics, enabling testing without shutting down the system.

Benefits of PD Monitoring

Implementing PD monitoring provides:

• Early detection of insulation defects

• Improved maintenance planning

• Reduced unplanned outages

• Increased equipment lifespan

• Enhanced personnel safety

Conclusion

Partial discharge monitoring is no longer optional for high-voltage systems.
It is a predictive maintenance tool that protects assets, improves reliability, and supports long-term network stability.

Need reliable PD diagnostics?
Contact Oryona to explore advanced partial discharge detection solutions.