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| 摘要: |
| 传统的电力变压器内部故障模型都是基于绕组的分析方法,忽略漏磁通、变压器铁芯涡流效应,且考虑铁芯非线性较少。为能进一步准确地描述变压器内部故障的暂态过程,并深入了解变压器内部故障机理,基于结构为三相五芯柱变压器模型,采用磁路分析方法建立了计及涡流效应、漏磁通及铁芯非线性等因素的三相五芯柱变压器内部故障仿真模型。模型从三相五芯柱变压器磁路出发,建立了磁链方程、电压方程,并根据铁芯和铁轭的磁通和电流关系及磁路关系列出磁导计算方程;给出了仿真模型的参数确定方法,其中参数确定与变压器的结构紧密相关。为了验证仿真模型的有效性,用该模型仿真了故障后较长时间进入稳态的情况,其结果与稳态的电路方法电流有效值计算结果相一致。仿真结果的暂态趋势与试验结果基本一致,从而验证了该模型的有效性。 |
| 关键词: 变压器,短路故障,暂态模型,仿真 |
| DOI： |
| 分类号:TM401.1 |
| 基金项目: |
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| Simulation of internal fault of three-phase five-leg transformer |
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HAO Wen-bin LI Qun-zhan
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| Abstract: |
| In traditional internal fault models of power transformers based on winding analysis,the leak flux and the eddy effect of iron-leg are ignored and the non-linearity of iron-leg is less considered.In order to adequately describe the transient process of power transformer internal fault and find out internal fault causes,a simulation model is established with the magnetic circuit method,which is based on the structural model of three-phase five-leg transformer and considers eddy effect,leak flux and non-linearity.The magnetic flux linkage equations and voltage equation are established according to the magnetic circuits and the magnetic conductance equation is listed according to the relations among magnetic flux,current and magnetic circuit.The method to determine the parameters of simulation model is given,which is closely related to transformer structure.The model is applied in the simulation of fault with long recovering time and the simulative result is same as that of virtual value calculation.The transient trend of simulation is basically in accord with that of experiment,which proves the validity of proposed model. |
| Key words: transformer,short-circuit fault,transient model,simulation |
