Research on Sealing Performance and Electrical Performance of Electrical Penetration Assembly in Nuclear Reactor Containment

Abstract Electrical penetration assembly (EPA) are electrical conduits mounted on the containment that serve to maintain the integrity of the containment pressure boundary and provide a path for cables to traverse the containment. Currently, low-voltage electrical penetration assembly (LV-EPA) is mainly made of organic materials to realize the sealing function, and it is not clear whether the performance of organic sealing materials will be degraded in the event of a nuclear reactor under extended design conditions (DEC-B). In this paper, a representative original-size LV-EPA is selected as the research object, and the equipment life test and the test for measuring the insulation and sealing performance of the LV-EPA under severe accidents are carried out by constructing a test setup that simulates severe accident conditions. The results show that: under the condition of 200°C and 0.6MPa, with the increase of test time, the electrical performance of LV-EPA remains good, but the sealing performance will be degraded step by step; after 72h simulated DEC-B test, the sealing performance and electrical performance of the equipment satisfy the standard requirements.