旋转变压器(角度传感器)的基本原理 Encoder Resolver.pdf

《旋转变压器(角度传感器)的基本原理 Encoder Resolver.pdf》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、E-learningResourcesinMicroelectronicsResolverUniversitätPaderbornDocumentInformation1.IntroductionAuthors:StaffofUniversitätPaderborn1.IntroductionTheresolveroperatesontheprincipleofarotarytransformer.Inarotarytransformertherotorconsistsofacoil(winding)which,togetherwiththestatorwindi

2、ng,constitutesatransformer.Theresolverisbasicallydesignedexactlyinthesameway,withthedifferencethatthestatorismadeupoftwowindingsdisplacedby90°tooneanother,insteadofonewinding.Theresolverisusedtodeterminetheabsolutepositionofthemotorshaftoveronerevolution,especiallywithservo-drives.Fur

3、thermore,thespeedandtheencodersimulationforthepositioncontrolcanbederivedfromtheresolversignal.Fig1.SchematicdesignofaresolverTherotoroftheresolverismountedonthemotorshaft.Boththestatorandtherotorareprovidedwithanadditionalwindingeachtoallowforbrushlesstransmissionofthestatorprimaryvo

4、ltagetotherotor.Withtheaidoftheseadditionalwindingstheprimaryvoltageofthestatorwindingwithacarrierfrequencyofabout8kHzistransmittedtotherotor(rotatingtransformer).Thetwowindingscarriedontherotorarecoupledelectricallysothatthevoltagetransmittedfromthestatortotherotorisalsopresentonthes

5、econdwindingoftherotor.Voltagesofdifferentmagnitudeareinducedinthestatorwindings,dependingonthepositionoftherotor.Thewindingthroughwhichthereisfullcurrentflowatg=0°(seeFig1.)hasthemaximumvoltagepresentatthispointintime.Iftherotorisrotating,thenvoltageV1onthiswindingdecreasesuntilithas

6、attainedthevaluezeroatanangleof90°.Iftherotorisfurtherrotated,thevoltageagainincreaseswithinversepolarityuntilithasagainreacheditsmaximumat180°.VoltageV1hasacosinecurveasenvelope.VoltageV2,whichisdisplacedby90°tovoltageV1,hasavalueof0Vat0°.Itincreasesuntilithasattaineditsmaximumvaluea

7、t90°,andthendecreasesagain.TheenvelopeofV2isthereforeasinecurve.Thisistheknownprincipleofamplitudemodulation.TheoutputvoltagesV1andV2arecalculatedasafunctionoftheinputvoltageVeby:Input:Output:whereg=rotoranglew=carrierfrequencyofVeVS=inputvoltagepeakvalueOutputvoltagesV1andV2ofthereso

8、lverP