80http://dlkc.cbpt.cnki.net电力勘测设计第1期DOI:10.13500/j.dlkcsj.issn1671-9913.2023.01.01410kV站用变回路电流互感器的选择唐忠达(南瑞电力设计有限公司,江苏南京211000)摘要:站用变回路负荷电流较小,随着系统短路电流越来越大,有时可达负荷电流的数千倍,互感器的选择难以同时满足测量及计量精度、继电保护整定、短路不饱和等条件,这是目前工程设计普遍遇到的难题。结合相关文献,指出了当互感器额定准确限值电流大于2倍的保护装置一次电流整定值,且裕度系数不小于2时,在互感器过饱和的情况下,仍能够确保继电保护正确动作,提出了站用变回路电流互感器的选择方法,最后通过工程实例,计算了站用变回路电流互感器额定一次电流比与准确限值系数。关键词:站用变;电流互感器;饱和;整定中图分类号:TM645文献标志码:A文章编号:1671-9913(2023)01-80-04SelectionofCurrentTransformerfor10kVAuxiliaryTransformerTANGZhongda(NARIElectricPowerDesignCorporation,Nanjing211000,China)Abstract:Theloadcurrentofauxiliarytransformercircuitissmall.Withtheincreaseofshort-circuitcurrentinthesystem,sometimesthousandsoftimesofloadcurrent,theselectionofcurrenttransformerisdifficulttomeettheconditionsofmeasurementandmeteringaccuracy,relayprotectionsetting,short-circuitunsaturated,whichisacommonprobleminelectricpowerengineeringdesign.Combinedwithrelevantliterature,itispointedoutthatwhentheratedaccuratelimitcurrentofthecurrenttransformerisgreaterthan2timesofthesettingvalueoftheprimarycurrentoftheprotectiondevice,andthecoefficientisnotlessthan2,therelayprotectioncanstilloperatecorrectlyundertheconditionofcurrenttransformeroversaturation.Theselectionmethodofthecurrenttransformerinthecircuitoftheauxiliarytransformerisproposed.Finally,theratedprimarycurrentratioandaccuratelimitcoefficientofcurrenttransformerintheauxiliarytransformeriscalculatedthroughanexample.Keywords:auxiliarytransformer;currenttransformer;saturated;protectionsetting*收稿日期:2021-03-17作者简介:唐忠达(1980—),男,高级工程师,从事电力工程设计与管理工作。0引言电流互感器作为变电站中重要的电气设备,其用途是将一次大电流变换成二次小电流,供仪表及二次装置实现测量、计量、监...