简介:本文论述感应电动机中的断裂导条检测问题。作为检测之根据的假设时,当转子导条断裂时,感应电动机的转子表观电阻将会增加,为了检测断裂导条,定子电压和电流的测量是通过一个用于转速和转子电阻同时估测的扩展卡尔曼滤波器进行的,特别是,对转子电阻进行估测并与它的正常值作比较,以检测断裂导条,在所建议的扩展卡尔曼滤波器方法中,状态协方差矩阵补充分加权。导致一个比较好的动态状态估测,它的主要优点是,甚至对一台空载的感应电动机,也能作出正确的转子电阻估测,作为该估测过程的一个部分,有必要对转子电阻中的热变化加以补偿,对于一台4-kW4极鼠笼型感应电动机所进行的计算机模拟,令人鼓舞地证实了所建议的无传感器断条检测技术的有效性。
简介:<正>NatureandaimoftheGroupGorporationChinaHydropowerEngineeringConsultingGroupCorporationsetupattheendof2002withtheapprovaloftheStateCouncilhadrestructuredsevenresearchinstitutesofinvestigationanddesign(Beijing,EastChina,Northwest,Mid-south,Chengdu,Guiyang,Kunminginstitutes)andChinaWaterResourcesandHydropowerConstructionEngi-
简介:<正>ChinaPowerEngineeringConsultingGroupCorporationestablishedonthefoundationofChinaPowerEngineering(Group)CompanyLtd.affiliateseightsolely-ownedemterprisesandcompaniesandaninstitution,theyare:Northeast,EastChina,Central-South.NorthwestandSouthwestpowerdesigninstitutes,EngineeringCompanyLtd.underGuohuaNorthChinaPowerDesignIn-stitute,ChinaPowerConstructionConsultationCorporation,ChinaPowerEngineeringConsultation(Group)CompanyLtd,andthePowerPlanningandDesignGeneralInstitute.
简介:<正>NatureoftheGroupCorporationChinaWaterResourcesandHydropowerConstructingGroupCorporationisastate-ownedenterpriseapprovedbytheStateCouncilandorganizedonthefoundationofChinaWaterResourcesandHydropowerEngineeringConstructionCompanyandrelevantenterprisesundertheformerStatePowerComorationofChina.Itsmainmembershipincludes23solely-ownedenterprisesand2stockholdingenterprises.
简介:利用飞秒激光三光束干涉在ZnO晶体表面制备微米-纳米复合周期结构。该结构由两部分组成:由激光干涉强度花样决定的微米长周期结构以及由飞秒激光偏振决定的短周期纳米条纹结构。利用800nm激光激发大面积的微米-纳米复合周期结构后发现,该结构的荧光强度得到了极大提高。显微发光照片表明,该结构在平板显示、高密度光存储以及光子晶体制备上都具有潜在的应用价值。