Beyond Efficiency in Grid Power Transformers

Evaluating power transformer proposals is usually limited to first cost and efficiency calculations, yielding a total cost of ownership over the” expected life” of the transformer.  This calculation is rendered meaningless if premature failure or high maintenance costs are incurred.  Additional insight into what is being proposed is needed to ensure long asset life and stem the "race to the bottom" in value being driven in the industry by so-called low evaluated price purchases.

What really determines the expected life is the field stress analysis derived during the design review.   Field stress calculations tell the expected performance of insulating media (both hard and liquid) to achieve electrical performance.  They are the basis of  the manufacturer's cost calculation and design philosophy, because modeling allows value-engineered minimums to reduce first cost of manufacture.  Higher stresses can degrade insulation and oil quality, cause gassing, increase oil processing interval, reduce resiliency to grid events.

Large grid power transformers must be designed to generate a price proposal.  By requesting field stress calculations, in addition to eficiency and first cost, your grid wil be more reliable and resilient.  Transformers are the longest lead time, most expensive and critical asset in power transmission. This simple addition to your specification helps ensure the best value.