Application of UHF PD Detection for Dead Tank Breaker (DTB)

Breakthrough Technology for Detecting Partial Discharge in Dead Tank Circuit Breakers

Dead tank circuit breakers have historically shown higher failure rates than their GIS counterparts—particularly in voltage classes above 300kV where failure rates exceed 1%. While Ultra High Frequency (UHF) partial discharge monitoring has successfully protected GIS equipment for over 20 years, applying this proven technology to dead tank breakers has remained an unsolved challenge. Until now.

This technical whitepaper from Qualitrol and ABB reveals how innovative frequency adaptation and sensor design have finally enabled reliable UHF PD detection for DTBs, overcoming obstacles that defeated previous approaches. The breakthrough addresses a critical vulnerability: particles and other defects inside dead tank breakers that can lead to catastrophic failures.

What You'll Discover:

Learn why conventional PD measurement methods fail on dead tank breakers. The paper explains how silicone rubber bushings generate surface discharges that mask internal problems, and why external disturbances from overhead lines overwhelm traditional detection systems. Understand the fundamental physics of why DTB bushings act as low-pass filters with relatively high cutoff frequencies.

Explore the engineering solution: specially designed UHF sensors that mount in existing gas valve openings, eliminating the need for breaker modifications. Discover how shifting the measurement frequency band above the bushing cutoff frequency effectively filters out external noise while maintaining sensitivity to dangerous internal discharges.

Review detailed defect simulation results demonstrating successful detection of the most common failure modes—free particles, busbar corona, and chamber corona. See how particles exhibit unexpected "floating element" discharge patterns as they slide across internal surfaces before lifting off. Learn about time-of-flight localization techniques that pinpoint defect locations within the breaker tank.

The research validates this methodology for both routine testing and continuous online monitoring applications, offering utilities a powerful new tool for preventing dead tank breaker failures.

Download this groundbreaking whitepaper to understand how UHF technology is finally bringing advanced condition monitoring to dead tank circuit breakers.