Online Monitoring Of Power Transformer Winding Faults And Software Verification

Power transformer has been widely used in many fields.With the aging of power transformer,its winding is easy to go wrong.These failures will have an influence on user and grid more or less.Therefore,it is necessary to investigate the detect technology of power transformer winding faults.First,This paper tells the research background and significance of this topic,this paper introduces the structure and the transformer fault,and a common online monitoring of transformer on-line monitoring scope and all kinds of fault diagnosis principle.Tthe background and meaning of the research is presented in this paper,and then,frequency.response analysis,short circuit impedance method and low voltage impulse method are introduced.When these techniques are used to detect the winding deformation,the transformer has to be switched off and taken out of service.Second,two most common models of power transformer are compared and three different methods to obtain distributed parameter are described.And then,a distributed parameter model used in this paper is presented.Based on distributed parameter model,this paper introduces a new online technique to detect internal faults within a power transformer.The technique is relying on constructing a locus between the voltage difference in the high.and the low.voltage sides of a particular phase against the input current.A digital image.processing technique is used to compare the healthy and faulty loci and to determine the type of fault.Unlike FRA which uses a sweep frequency in the range of 2 MHz,this technique is performed at the power frequency and,hence,meet the national demand pushed the smart grid construction,satisfy the mechanical state of transformer on-line monitoring,effectively prevent the transformer winding deformation cause accidents online monitoring of transformer mechanical conditions can be realized.Moreover,the method does not call for any additional equipment since it uses the metering equipment attached to any power transformer to monitor the input/output voltages and the input current.Also,the method does not call for an expert person to conduct or to analyze the results.