Bushings
The TOTUS Bushing Monitor uses integrated intelligence and analytics to provide reliable and intuitive information to asset managers about bushing health.
The TOTUS Bushing Monitor uses integrated intelligence and analytics to provide reliable and intuitive information to asset managers about bushing health.
According to statistics published by IEEE, IEC and CIGRE, bushings contribute to roughly 15-30% of transformer failures globally.
In over 40% of cases the failure resulted in catastrophic consequences such as fire, tank rupture and explosions. CIGRE TB 755 reports:
bushings cause 5% to 50%, of transformer failures
bushing failures are the most common cause of transformer fires and can cause huge collateral damage in the switchyard
30% of generator step-up transformer failures are caused by a bushing malfunction
Online monitoring of bushings, through monitoring of internal insulation (capacitance / Tan Delta or Power Factor) and the internal electrical activity (Partial discharges) enables asset managers to detect a fault at its very preliminary stage, allowing action to be taken before reaching a critical and irreversible stage.
TOTUS allows for correlation and causation to determine failure modes, driving prescriptive actions. We monitor the following on bushings:
Thanks to monitoring a combination of leakage current & partial discharges we have saved over $10M in damages to bushings for our customers including RIP bushings
RIP bushings are made with a void-free impregnation process, designed for a Partial Discharge free operation. However, a combination of extraordinary operating and external events can result in PD in the bushings.
The resin material is not able to withstand the PD activity and will lead to fast degradation and short circuit.
Monitoring PD within the bushings is critical and allows early detection of faults, allowing for fast diagnoses and action. The Image to left shows PD trending in bushings on a RIP bushing.
Early detection of PD can significantly improve risk diagnosis, driving quicker accurate decision making.
Recognising the PD pattern makes it possible to understand the nature of the defect and correlate this with leakage current to determine the best technical action or test. In over 70% of cases monitored by Kelvatek PD was a factor, often in early stages. PD monitoring identifies:
To learn more about our capabilities in PD detection methods, click below to read our customer case study
A successful online PD program can help to inform prescriptive actions for asset managers. When selecting a PD solution, it is important to stick to four key principles:
With reliable PD monitoring, asset managers can screen their transformer fleet and focus only on those transformers with active and repetitive PD.
"Monitoring of Partial Discharges can be easy to apply and understand if put in the right context, correlation of PD with other parameters can help to provide more accurate prescriptive actions and decision making."
Dr Marco Tozzi - Senior Product Manager, Camlin Group
Learn more about our bushing monitoring solution by reading our paper on 'Bushing Failure Prevention Through Online Monitoring'.
To learn more about any of our other asset monitoring capabilities, simply click below.
Simply complete this enquiry form or call us on 028 9262 6989 (UK) to speak to a member of our team.