The　transmission　lines　need　to　be　modeled　accurately　to　predict　the　voltage　reflections　and　EMI　levels　of　the　converter　system.　In　this　paper,　a　transmission　line　model　based　on　fast　vector　fitting　algorithm　is　proposed.　At　high　frequencies,　the　parasitic　capacitance　of　the　cable　conductor　causes　the　cable　impedance　to　resonate.　Due　to　skin　effect　and　proximity　effect,　the　cable　parameters　change　with　frequency.　The　frequency　equivalent　model　is　used　to　characterize　the　effect　of　cable　parameters　varying　with　frequency.　When　cable　is　open-circuited　and　short-circuited,　and　the　high-frequency　impedance　characteristics　of　the　cable　are　measured　using　an　impedance　analyzer.　Through　the　relationship　between　measured　impedance　and　model　impedance,　the　impedance　of　the　model　is　obtained.　The　impedance　is　fitted　by　fast　vector　fitting　algorithm.　Finally,　the　feasibility　and　validity　of　the　proposed　model　are　verified　by　comparing　the　simulation　and　measurement　results　in　the　frequency　and　time　domains.　©　2022　The　authors　and　IOS　Press.