Low　frequency　spectral　lines　based　on　frequency　domain　dielectric　spectra　contain　multiple　conductance　dispersion　processes.　In　order　to　solve　the　lack　of　low-frequency　response　analysis　method　and　imperfect　equivalent　circuit　model,　Kramers　Kronig　transformation　method　is　used　to　analyze　the　conductance,　infinite　frequency　capacitance　and　relaxation　process,　and　then　introduce　the　Dissado-Hill　model　to　establish　the　low-frequency　dielectric　response　equivalent　circuit　model.　Finally,　the　oil　paper　with　different　moisture　content　was　prepared　Insulation　samples　underwent　FDS　measurements,　and　the　obtained　frequency　domain　test　data　were　analyzed　by　analytical　spectral　line　analysis　and　equivalent　circuit　model　parameter　identification.　The　results　show　that　the　Kramers　Kronig　transform　can　effectively　uncouple　and　analyze　the　polarization　process,　conductance　process　and　infinite　frequency　capacitance,　and　it　also　proved　that　the　Dissado-Hill　model　has　good　fitting　with　different　moisture　content　sample.　©　2022　IEEE.