关键词: 控制力矩陀螺, 框架, 永磁同步电机, 超低转速, 跟踪微分器

Abstract: Atultra-lowspeed，theprecisionofgimbalspeedmeasurementisakeyfactorwhichinfluencesthecontrolaccuracyofacontrolmomentgyro（CMG）gimbalsystem.Focusingontheproblemofnoiseamplificationbroughtbyconventionalfirst-orderbackwarddifferentiatorwhencalculatingultra-lowspeed，areal-timespeedestimationmethodbasedonanonlineartrackingdifferentiatoranditsdiscretetimeexpressionusingthefourthorderRunge-Kuttamethodwasproposed.Acompositespeedmeasuringmethodwaspresentedtosolvethetrackingdelayproblemwhenusingtrackingdifferentiatorsdirectly.Then，thenumericalsimulationandexperimentwereconducted.Thesimulationresultsdemonstratethatthespeedestimationmethodproposedcouldreducethequantizationnoisesbroughtbytachometersandmeasurementnoises.Theexperimentalresultsshowthatbyusingtracking-differentiatorsthefluctuationofgimbalspeedisreducedby67.1%.

Key words: controlmomentgyro（CMG）, gimbal, PMSM, ultra-lowspeed, trackingdifferentiators