A　bearingless　motor　needs　to　keep　stable　suspension　during　standstill　and　startup　processes,　and　accurate　information　detection　of　the　radial　displacement　of　the　rotor　is　a　key　for　the　stable　suspension　operation.　However,　sensor　applications　are　sensitive　to　environments,　thus　reducing　system　reliability,　and　increasing　costs.　A　novel　radial　displacement　sensorless　control　method　with　high-frequency　current　injection　for　single-winding　bearingless　flux-switching　permanent　magnet　motor　is　proposed　to　address　the　stable　suspension　sensorless　control　during　startup.　First,　based　on　the　mathematical　model　of　inductance,　the　relationship　between　the　amplitude　of　the　effective　high-frequency　bias-EMF　and　rotor　radial　displacement　is　established　with　the　high-frequency　rotating　current　injected　into　the　torque　plane.　The　amplitude　of　the　effective　high-frequency　bias-EMF　is　extracted　by　the　linear　sinusoidal　tracker.　Thereafter,　based　on　the　relationship　between　the　amplitude　of　the　bias-EMF　and　rotor　radial　displacement,　a　rotor　radial　displacement　observer　is　constructed.　Finally,　combining　the　observed　displacement　with　the　active　disturbance　rejection　control　method,　a　high-performance　control　strategy　with　radial　displacement　sensorless　control　strategy　is　constructed.　The　theoretical　analysis　and　experimental　results　verify　the　validity　of　the　proposed　method.　©2023　Chin.Soc.for　Elec.Eng.