Three-phase　Vienna　PFC　circuit　is　widely　used　because　of　its　high　power　factor　and　low　harmonic　current.　In　this　paper,　dual　closed-loop　PI　control　strategy　is　used　to　analyze　and　design　the　circuit　control　loop.　For　the　problem　that　When　the　PI　controller　is　saturated,　the　integral　part　cannot　be　desaturation　in　time,　thus　affecting　the　response　speed　of　the　circuit.　The　design　of　an　integral　modified　PI　controller　is　proposed.　On　the　basis　of　the　traditional　double　closed　loop　PI　control　strategy,　the　integral　correction　link　is　added　to　speed　up　the　dynamic　response　of　the　system.　The　simulation　model　of　the　system　is　built　in　MATLAB,　and　the　response　speed　of　the　improved　circuit　is　analyzed　and　compared.　The　effectiveness　of　the　Vienna　rectifier　system　and　the　superiority　of　the　proposed　controller　are　verified　by　simulation.　©　2018　IEEE.