The　Weibull　distribution　model　was　used　to　evaluate　the　life　distribution　of　the　high-voltage　clips　in　an　off-stack　nuclear　test　system　of　a　nuclear　power　plant.　Based　on　the　characteristics　of　the　nuclear　power　plant,　we　propose　to　add　the　proportion　of　failure　data　and　non-failure　data　in　the　calculation　based　on　the　original　data,　and　use　the　particle　swarm　algorithm　to　find　the　optimal　weibull　distribution　model　parameters　and　cable　life　distribution　curve.　The　results　show　that　the　high-voltage　clamps　of　this　nuclear　power　plant　start　to　fail　after　about　1.7 years　of　operation,　and　enter　the　aging　period　in　about　5.6 years,　with　a　maximum　life　of　about　8 years.　This　approach　for　the　unfailed　data　provides　a　new　idea　of　parameter　estimation　for　the　case　of　less　failure　data.　©　2022,　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.