On the Role of Power Transformer Design For Resilient Future Electric Energy Systems

Power transformers play a key role in electricity systems as long as alternating current (AC) grid infrastructure is the preferred technical solution for transmission and distribution of electric energy. Further, the world-wide demand of electric energy is going to grow steadily in the next decades, and new challenges have arisen in terms of grid operation, and asset management. First, financially supported intermittent feed-in of renewable energy sources, partially in remote areas. Second, different mixtures of AC and direct current (DC) technology applied in the grid in addition to a rising share of converter based supply, and hence diminishing system inertia. Third, growing concerns about the vulnerability of the electric grid infrastructure to several exogenous system threats.

However, the current economic evaluation of reliable and resilient infrastructure, hence the methods to calculate the total cost of ownership (TCO) of power transformers, given the advancements in power transformer design, may not trigger the right incentives for investments in respective reinforcements, or new technologies.

The aim of this paper is to review some the most recent advancement in power transformer design with focus on the previously mentioned challenges in power system operation, and to highlight the problematic setting of focusing solely on purchase price and loss evaluations for a critical system element such as a transformer. It can be concluded that further improvements in the life cycle costs evaluations, and the design of specifications are needed in order to narrow the commercial gap between technical innovations and its remuneration.