Cost-effectiveness of base isolation for large transformers in areas of high seismic intensity

Abstract

One of the most important components of an electrical substation is its power transformer, but this component is vulnerable to earthquakes. Several studies have demonstrated the good potential of base isolation to improve the seismic resistance of transformers. However, cost-effectiveness of a base isolation system is as important to the managers of a power grid as its isolation efficiency. Therefore, to investigate the cost-effectiveness of base isolation for large transformers, the framework of this two-part study comprised: (1) shaking table testing and (2) cost-effectiveness analysis. In the shaking table testing, the isolation efficiency of a friction pendulum system for a 220 kV transformer-bushing system was validated. In the cost-effectiveness analysis, the converter transformers of a typical substation were taken as examples to calculate the expected cost in a single earthquake event and the expected total life-cycle cost with/without the base isolation. The base isolation could impart considerable economic benefits in an extreme earthquake event and significantly reduce the risk of unacceptable earthquake-induced losses during the life period. Together, these two parts demonstrated the great cost-effectiveness of base isolation for large transformers in areas of high seismic intensity, underscoring the importance of further development and applications of this technology.

Keywords:

• Base isolation
• cost-effectiveness
• friction pendulum
• shaking table testing
• transformer-bushing system

Additional information

Funding

This work was supported by the National Natural Science Foundation, China under Grant [No. 51878508 and National Key R&D Program, China under Grant No. 2018YFC0809400.National Natural Science Foundation of China; National Key R&D Program of China.