Why Do Transformers Fail?

With an aging infrastructure and extreme weather conditions, transformers may sometimes fail due to various reasons. Are the causes the same for all incidents?Transformer Failure Fire Veracity Asset Management In “An Analysis of Transformer Failures”, William H. Bartley, P.E., from Hartford Steam Boiler Inspection and Insurance, points out key elements regarding transformer failures.

The average age at failure is 18 years. Most of the transformers installed in the 1950s to 1980s have entered the aging part of their life cycles. “Power consumption continues to increase at a rate of about 2 percent per year, even though installation of new transformers is declining.” (William H. Bartley).

 Overview of the main causes of failure: Power Transformer Failure Veracity Asset Management Group

Preventing transformer explosions, leakage and other damages is not always possible. Factors like a proper installation and operation, oil test and thorough maintenance can help decrease failures. Nevertheless, even with the best efforts, no one can prevent a lightning to strike a transformer or other electrical equipment.

The bathtub curve

The following graph describes the relative failure rate of a whole group of similar products. During their life cycle, products will go through three different periods of failure rates, which explains the “bathtub” shape.

Bathtub Curve Failure Rate Veracity Asset

Let’s describe them:

  • Infant Mortality: failures are the least expected. Design, manufacturing or material defects are common causes and requires from the manufacturer a deep analysis of the incidents.
  • Normal Life, also called Useful Life: random failures occur. This is the lowest constant failure rate.
  • End of Life Wear-Out: wear and tear make products fail more often, and signal the end of their life cycle.

As mentioned by William H. Bartley, a large population of transformers is now reaching the end of life wear-out stage. This is a challenge for companies to anticipate upcoming failure, as the lead time for new transformers is from 6 months on to a couple of years, and the extreme weather is also increasing risks.

How then can we improve our answer to such issues?

Transformers are considered as critical spares. The lack of back-up slows down utility companies’ actions when a failure happens. Sourcing the right equipment with the right timing is a challenge that companies in the energy sector have to take up. One of the most relevant solutions is a collaborative platform specifically designed for the utility industry.

This is why Veracity Asset Management Group has developed Veracity Connect, a cloud-based platform designed to foster collaboration among utility industry members, suppliers and resellers. Connecting the right people, sharing knowledge and expertise allow the utilities to have immediate access to critical spares data and strategic management.

Veracity Connect, collaborative platform

When a transformer shows risks of failure – or age – the company can adopt a proactive approach to critical spares management and quickly locate a replacement. It cannot prevent the failures, but it helps utilities avoid lengthy negative situations and keep delivering quality customer service.

Contact us at 1-866-694-1252 or info@veracityamg.com. We will be glad to answer your questions and bring you the best of our services.

Transformers Asset Management Cloud Veracity ConnectOur website: http://www.veracityamg.com

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Sources :

“An Analysis of Transformer Failures”, William H. Bartley, P.E., Hartford Steam Boiler – http://ow.ly/AciXd

The Transformer & Electrical Co Ltd – General Causes of Transformer Failure in the Field – http://www.teccoltd.com/failure.html

The Bathtub Curve and Product Failure Behavior – http://www.weibull.com/hotwire/issue21/hottopics21.htm

1 thought on “Why Do Transformers Fail?

  1. Pingback: Transformers: An Essential Link of the Electrical Grid | Veracity Asset Management Group

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