Remaining useful life estimation of critical DIII-D subsystems

Abstract

DIII-D plays a vital role in the development of the physics basis for fusion energy and the ITER design. Designed and built in the early 1980’s, the system started operations in 1986 and has provided a reliable platform for fusion experiments for over 30 years. A hallmark of DIII-D operations has been its ability to adapt to the changing needs of the fusion research community and support a wide range of tokamak experiments for various stakeholders. An important factor in ensuring continued reliable operations is gaining a thorough understanding of the remaining useful life (RUL) of critical DIII-D systems by means of quantitative assessments of RUL. General Atomics has conducted a pilot RUL assessment project to develop an RUL estimation methodology applicable to various DIII-D systems and demonstrate its feasibility on a critical subsystem (i.e. the F8 field shaping coil). The pilot F8-coil RUL assessment project showed that under typical operating conditions, the F8-coil may be expected to achieve an overall life of >50 years and/or >106 shots and demonstrated that employing reliability engineering techniques coupled with modern analytical tools, quantitative estimates for RUL can be developed with reasonable investment.