In　this　paper,　we　study　the　flux-weaken　control　with　the　method　of　the　advanced　angle　of　currents　in　the　interior　permanent　magnet　synchronous　motor　of　the　electric　cars.　We　adopt　the　first-order　digital　filter　to　handle　the　data　acquired　from　three　phase　currents　and　realize　the　speed　and　current　double　closed　loop　control　by　the　incremental　PI　regulation.　In　Matlab/Simulink,　we　build　the　flux-weaken　control　system　simulation　model　with　the　double　closed　loop.　For　the　40kw　IPMSM,　we　develop　the　experimental　platform　based　on　TMS320F28335.　The　simulation　and　experiment　archive　a　good　control　effect.