Abstract: Sensorlesscontrolstrategyforrotorsystemofthesinglegimbalcontrolmomentgyro(SGCMG)couldreducecomplexityandpromotereliabilityofthewholeset.Themethodsbasedonthebackelectromotiveforce(EMF)detectionofthehalfbridgedrivebrushlessDCmotor(BLDC)andthedisturbanceeliminatingmethodswithoutlowpassfilterwereproposed,whichcouldachieveshighdetectionprecision.Forthestartupprocess,afoursegmentstrategywasproposedincludingorientationsegment,I/fstartupsegment,speedestimationstartupsegmentandswitchsegment,whichrealizedareliablestartupprocess.Simulationsandexperimentsprovetheeffectivenessoftheproposedmethod.ReliableandaccuratesensorlesssystemforSGCMGhighspeedrotorisrealized.

Key words: Singlegimbalcontrolmomentgyro, Highspeedrotor, Sensorless, BackEMFdetection, Openloopstartup