Implementation of power electronics in nuclear power plants: DC electrical system conceptual design and its financial analysis

Abstract

A Power Electronic (PE) device is a semiconductor-based device which enable many advanced conversion of electricity which have been used widely in many industries. Due to the recent development in both circuit design and switches, these devices have become more competitive to traditional AC technologies. The design section of this study demonstrates the feasibility of high-level implementation of PE technology to a Nuclear Power Plant electrical system by conceptually designing a DC electrical system and comparing it to a reference AC system. The DC system meets the same design requirements as the AC system does. Furthermore, results from the financial analysis illustrate the advantages and disadvantages of implementing PE technology. Overall, the DC electrical system is able to significantly reduce generating costs due to, mostly, the more efficient pumping control with Variable Speed Drive. Other design options such as systems with less PE device implementation are examined in this study, which shows similar result. Besides, the technological benefit and challenge is discussed along with possible application to other plants, regulatory impacts, and scaling of the system. Additionally, several sensitivity analyses regarding the equipment cost and O&M cost are also performed. In summary, the implementation of PE technology seems to have financial and technological benefits, but there are also challenges associated with the technology itself and the standardization.