4 June 2020

On-line monitoring solutions to detect potential transformer failures

Understanding the reasons why power transformers and other energy infrastructure assets fail is critical in the development of industry standards, products and practices that can limit risk and improve the overall reliability of energy networks. Capturing failure data enables all stakeholders to determine areas for improvement and predict future behavior when managing electric power system assets.

Below is a visual representation of data collected from the standardized survey that was developed to allow network operators capture the causes of power transformer failures.

Based on CIGRE Transformer Survey Data collected by its Study Committee A2

Through an understanding of the most common causes of power transformer failures, it is possible to develop an on-line monitoring strategy that reduces risk by providing advanced warning of potential problems developing in a transformer.

Why on-line monitoring?

Historically, manual processes and testing procedures have been used to detect transformer issues and supplement scheduled maintenance. But these manual processes only provide a snapshot of the transformers condition at a moment in time and cannot be fully relied upon to predict impending issues or failures. On-line monitoring continually checks the status of the transformer, providing actionable data that can be used to schedule essential maintenance or, ultimately in the event of a pending catastrophic failure, shut down the asset.

By using the failure data Weidmann has available, transformer operators and manufacturers can determine which on-line monitoring solution can provide them with the highest return on investment based on budget and infrastructure in place. A solution that offers them the highest likelihood of providing data that increases the reliability of the electrical asset, while minimizing the need for unscheduled or unnecessary maintenance.

Is it worth the investment?

It is common decision to repair a faulty transformer to make savings. Nevertheless, this operation already costs up to 80% of the price of a new transformer. On the other side, investing in monitoring devices represents less than 4% of the cost of a new transformer. Not only do these monitors have a low total cost of ownership, but they will also lenghten the lifespan of the transformer: using monitoring solutions decreases the failure rate by nearly 43%, avoiding unnecessary repairing costs.

On-line monitoring with Weidmann Electrical Technology

Taking a simple statistical approach, Weidmann Electrical Technology offers a comprehensive, cost effective suite of monitoring products that enables operators to capture key data in near real-time. This data can significantly contribute to reducing failures and improving management strategies for key assets.

By analyzing failure data, a combination of InsuLogix® on-line monitoring solutions can be used to significantly reduce your risk of transformer failure, provide data to enable needs-based maintenance planning, and optimize the life of your transformer asset.

50.2% of potential failure causes detected

InsuLogix® H/M
Cost effective solution to catch faults in transformers, with high-tech detection of hydrogen gas and moisture-in-oil.
Communication protocols for data acquisition: DNP3, Modbus

38.8% of potential failure causes detected 

InsuLogix® SGS
This smart gauge provides a cost effective solution, displaying liquid and winding temperature data, with the ability to calculate hot spot and transformer loss of life per IEEE and IEC mathematical models.
Communication protocols for data acquisition: DNP3, Modbus

InsuLogix® T / Smart Spacer®
Monitors up to 16 measurement channels and offers reliable hot spot winding temperature monitoring. Uniquely available with optional Certified Smart Spacer® for the most advanced and robust transformer temperature monitoring system available.
Communication protocols for data acquisition: DNP3, IEC61850, IEC60870-104

17.2% of potential failure causes detected 

InsuLogix® B
Acquires, analyzes and trends data pertaining to AC insulation power factor of high voltage bushings to determine accurate condition and potential failures.
Communication protocols for data acquisition: DNP3, IEC61850