The　three-phase　Vienna　rectifier　is　widely　used　in　communication　power　supply,　wind　power　generation,　and　electric　drive　due　to　its　advantages　of　no　dead　zone　between　the　same　switch　bridge,　high　reliability,　and　low　harmonic　content　of　input　current.　The　traditional　control　methods　applied　in　Vienna　rectifiers　mainly　include　proportional-integral　(PI),　single-period　control,　etc.　These　traditional　control　methods　have　simple　principles　and　convenient　designs.　However,　with　the　increasing　requirement　of　Vienna　rectifier　performance　and　the　increasing　complexity　of　the　application,　the　traditional　control　method　is　difficult　to　obtain　a　satisfactory　control　effect.　In　order　to　improve　the　control　performance　of　the　Vienna　rectifier　under　the　complex　environment,　a　model-free　predictive　current　control　strategy　based　on　adaptive　super-twisting　sliding　mode　observer　(ASTSMO-MFPCC)　is　proposed.　Firstly,　an　ultra-local　model　independent　of　system　physical　parameters　is　constructed　by　analyzing　the　mathematical　model　under　the　condition　of　model　mismatch.　Secondly,　a　super-twisting　sliding　mode　observer　is　designed　to　estimate　the　unknown　part　of　the　ultra-local　model,　which　can　effectively　suppress　the　influence　of　system　disturbance.　At　the　same　time,　an　adaptive　gain　was　designed　to　dynamically　adjust　the　parameters　of　the　super-twisting　sliding　mode　observe　to　solve　the　gain　selection　problem.　Finally,　a　two-step　predictive　cost　function　is　constructed　to　realize　the　model-free　predictive　current　control.　To　validate　the　performance　of　ASTSMO-MFPCC,　a　model-free　predictive　current　control　algorithm　based　on　traditional　sliding　mode　observer　(SMO-MFPCC)　is　realized　and　compared　under　steady-state,　dynamic,　and　parameter　mismatch　conditions.　The　simulation　and　experimental　results　show　that　the　bus　voltage　of　the　ASTSMO-MFPCC　algorithm　can　reach　the　steady　state　faster,　and　the　amplitude　of　voltage　change　is　small　in　the　given　voltage　and　load　mutation　experiments.　From　the　simulation　results　of　load　mutation,　it　can　be　found　that　the　observer　parameters　can　adjust　adaptively　after　the　load　changes.　In　the　steady-state　experiment,　the　A-phase　current　THD　of　SMO-MFPCC　is　6.7%,　while　that　of　the　ASTSMO-MFPCC　algorithm　is　only　4.26%.　In　the　parameter　mismatch　experiment,　the　D-axis　current　of　SMO-MFPCC　has　a　significant　change　and　needs　a　long　time　to　stabilize,　and　the　current　fluctuation　is　as　high　as　2.7　A.　The　ASTSMO-MFPCC　has　a　smaller　change　in　D-axis　current,　and　the　current　fluctuation　is　only　2.1　A.　According　to　the　simulation　results　of　inductance　parameter　mutation,　the　chattering　observed　by　the　adaptive　super-twisting　sliding　mode　observer　is　significantly　smaller.　Simulation　and　experimental　results　verify　the　feasibility　and　correctness　of　the　proposed　method,　and　the　following　conclusions　are　drawn:　(1)　This　strategy　combines　model-free　control　with　predictive　control　so　that　the　system　is　independent　of　the　exact　physical　parameters　of　the　rectifier　during　operation.　(2)　The　control　performance　degradation　problem　of　a　system　caused　by　the　chattering　of　the　traditional　sliding　mode　observer　is　solved,　and　the　disturbance　suppression　ability　is　improved.　At　the　same　time,　the　adaptive　gain　is　designed,　and　the　observer　parameters　are　adjusted　dynamically　to　simplify　the　gain　selection　effectively.　(3)　The　comprehensive　comparison　with　the　SMO-MFPCC　method　confirms　that　the　ASTMO-MFPCC　strategy　has　better　dynamic　and　stable　performance　and　anti-interference　ability.　©　2024　China　Machine　Press.　All　rights　reserved.