When　the　high-speed　motor　is　running,　due　to　its　ultra-high　speed　and　the　current　frequency　of　thousands　of　hertz,　the　loss　value　of　each　part　will　increase　greatly.　High　loss　will　inevitably　lead　to　high　temperature　rise.　Excessive　temperature　rise　may　cause　problems　such　as　motor　insulation　failure,　permanent　magnet　demagnetization,　and　insufficient　mechanical　strength.　This　paper　establishes　a　lumped　parameter　thermal　network　model　of　a　20 kW,　10　Wrpm　surface-mount　2　pole　6　slot　high　speed　permanent　magnet　motor,　and　conducts　a　finite　element　analysis,　and　analyzes　the　effect　of　a　cooling　method　in　the　stator　conductor.　The　final　finite　element　analysis　results　show　that　the　copper　conductor　temperature　rise　of　this　high-speed　motor　is　254.49　°C,　and　the　maximum　temperature　rise　of　the　motor　is　258.71　°C.　When　the　copper　conductor　has　an　internal　cooling　structure　and　cooling　water　is　passed,　the　copper　conductor　temperature　rise　almost　drops　to　0　°C,　and　the　maximum　temperature　rise　of　the　motor　has　also　dropped　to　80.27　°C.　©　2021,　Beijing　Oriental　Sun　Cult.　Comm.　CO　Ltd.