Critical electrical infrastructure faces an unseen threat that operates silently and creates gradual deterioration until operations suffer abrupt interruptions from system failures. Such events do not exist only in science fiction movies but represent real-life consequences of undetected partial discharge (PD).

High-voltage electrical systems face a substantial threat from partial discharge, although this serious problem usually stays unnoticed until system breakdowns occur. When undiscovered, PD causes massive system breakdowns, which produce expensive shutdowns and safety-threatening situations.

This article analyzes the troubling nature of PD and demonstrates the vital importance of early detection mechanisms for worldwide utility and industrial facilities.

What is partial discharge?

Partial discharge is an electrical event that appears when insulation in high-voltage equipment starts breaking down inside its structure. The slow deterioration process progresses over months or years until it reaches a system-wide breakdown stage unlike full electrical breakdowns that immediately fail equipment.

PD emerges from weak insulation areas inside aging transformers, switchgear components, cables, insulators, or any part where insulation deteriorates. Different forms of discharge exist, including corona discharge, surface, and internal discharge, which have distinct damaging effects.

The biggest challenge? The nature of partial discharge prevents direct human perception because it remains undetectable to both eyes and ears until observed through specialized detection instruments.

What makes partial discharge a serious issue for electrical systems?

It weakens electrical insulation

The main purpose of electrical insulation within systems is to block undesired current transmission. PD attacks insulation by producing small areas of damage that accumulate throughout time. The deterioration process puts insulation at risk of failure, thereby producing short circuits, arc flashes, and complete system breakdowns.

It causes unplanned power outages

Unstable electrical infrastructure directly affects the reliability of power delivery. PD attacks on system components make them more vulnerable to random hardware breakdowns.

Utilities, industrial facilities and vital operational sites such as hospitals and data centers need uninterrupted power supplies in order to function. Power disruptions resulting from unidentified PD failures lead to expensive system downtime and operational interruptions that also pose safety hazards for personnel.

It leads to expensive repairs and replacements

The costs associated with PD-related system breakdowns become extremely high. The process of repairing a transformer during failure typically costs hundreds of thousands of dollars, combined with secondary expenses from lost business functions. Early partial discharge detection and proactive care minimizes emergency repair situations that create costly and damaging effects on infrastructure.

It poses safety risks to workers and equipment

Partial discharge leads to equipment harm and also produces unsafe working situations. When insulation fails, it creates dangerous scenarios that lead to electrical fires, generate arc flashes, and equipment explosions, which pose life-threatening risks to workers and surrounding facilities. An early PD detection allows utilities to establish safer working sites.

The impact of partial discharge on electrical assets

Different electrical assets undergo specific impacts during partial discharge events.

Transformers

Transformer failure occurs when PD damages the winding insulation, which leads to voltage regulation failure. This creates extensive power outages, which makes partial discharge detection a necessity for maintaining electrical grid stability.

High-voltage cables

PD activates over time to form pinhole defects in cable insulation, which finally results in cable failure. The cost of underground high-voltage cable replacement and disruptive procedures makes predictive maintenance an absolute necessity.

Switchgear and circuit breakers

PD in switchgear equipment results in breakdown of insulation followed by system malfunctions and breaker tripping events. Such power disruptions affect critical operations while generating additional maintenance expenses.

Insulators and bushings

The insulation of bushings and overhead insulators becomes progressively thinner because of PD activity, which results in flashovers that decrease system reliability. It is essential to keep these components free of PD to avoid systemic failure incidents.

What steps exist to detect partial discharge?

The early detection of partial discharge enables preventive measures to stop it from becoming a failure-causing situation. The market offers multiple cutting-edge solutions which help utilities and industries track PD activity.

Acoustic imaging technology

The ultrasonic signals produced by PD fall outside the audible range of human hearing. Acoustic cameras possess the ability to detect and display such signals, which lets maintenance staff exactly locate PD areas. This detection technique proves highly effective for identifying corona discharges and surface discharge on open-air electric equipment.

Ultrasonic testing

Handheld ultrasonic sensors have the capability to identify high-frequency signals generated by PD activity during inspection. Ultrasonic testing proves valuable when examining enclosed electrical components like switchgear and transformers.

Partial discharge monitors

Strategic installations of predictive PD monitoring devices within critical infrastructures enable operators to obtain current data about insulation performance. The monitoring systems detect rising PD levels, thus sending warnings to operational teams who can intervene actively before equipment breakdown happens.

Thermal imaging

Thermal cameras read PD-related insulation failure indications through their ability to detect temperature hotspots. Predictive maintenance programs make extensive use of infrared cameras for their inspections.

Preventing partial discharge to ensure power reliability

Regular condition monitoring

Modern electrical infrastructure demands continuous maintenance because the “fix-it-when-it-breaks” methodology is outdated. PD detection tools should be used during planned inspections to catch problems before they escalate into major issues.

Upgrading aging equipment

PD typically occurs in aged electrical components that show signs of deteriorating insulating materials. Upgrading the aging infrastructure with modern safety-resistant electrical equipment produces more reliable power systems.

Implementing predictive maintenance strategies

PD monitors and acoustic cameras provide maintenance personnel with data that allows them to move from reactive to predictive maintenance strategies. PD monitoring strategies help electrical assets operate longer periods before expense-driven breakdowns occur.

Training personnel on PD awareness

Proper knowledge and training enable the prevention of electrical failures that originate from PD occurrences. Industrial staff members must learn PD detection approaches and best maintenance practices to maintain reliability systems through proactive interventions.

Conclusion

Power reliability faces a significant but unnoticeable menace from partial discharge. Modern detection technologies paired with proactive maintenance practices enable organizations to prevent PD risks, which leads to extended electrical asset life and uninterrupted power supply. Organizations that monitor their infrastructure with acoustic imaging cameras and stay vigilant can protect their facilities from failure events, which lead to operational continuity.