基于改进ΔU⁃I轨迹法的变压器绕组变形在线检测方法

Online Detection Method on Winding Deformation of Transformer Based on Improved ΔU⁃I Locus Method

绕组变形是电力变压器最容易发生的故障之一,未及时检测到的绕组变形增加了变压器发生灾难性事故可能性。为了准确灵敏地检测出任何轻微的绕组变形,在原有ΔU⁃I轨迹法的基础上提出了改进方法。文中首先阐述了原有方法的原理,并通过仿真说明了其在应用中所存在的缺陷。基于原有方法的不足,提出了负载标准化方法,解决了原方法在实际应用中受负载影响较大的问题;在此基础上,进一步提出了改进方法,并探究了测量误差对原方法和改进方法的影响情况。仿真结果表明,与原方法相比,改进方法在反映轻微绕组变形时具有更高的准确度和灵敏性。

Winding deformation is one of the most common faults in power transformers.The winding deformation which has not been detected in time increases the possibility of catastrophic accidents of transformer.In order to detect any slight winding deformation accurately and sensitively,an improved method is proposed on the basis of the original ΔU-I locus method.The principle of the original method is described firstly.The defect of it in the application is illustrated by simulation.Based on the shortcomings of the original method,the load standardization method is proposed,which solves the problem of the original method with big load influence in practical application and,on this basis,the modification method is proposed further.The influence of the measurement error on the original and the improved method is also discussed.The simulation results show that the improved method,compared to the original method,has higher accuracy and sensitivity in reflecting slight winding deformation.