Research On The Live Detection For Winding Deformation Of 110kV Transformers Based On FRA

Transformer is one of the important equipments in power system.Its safe operation is directly related to the security and reliability of power supply.With the increasing of the power network capacity,the faults of the transformer caused by the winding fault are on the rise.Traditional line detections are costly,and charged detection can detect transformer winding deformation in case of power failure,so the study of transformer winding deformation charged test method and device is significant to stable operation of power transformer and reduction of accident for transformer safe.According to deformation analysis method for the existing winding,A test method for transformer bushing winding deformation based on the test signal of the end shield of the neutral point is put forward.In this method,the frequency domain transfer function is obtained by measuring the first end of the neutral point and the first terminal of the high voltage winding,and then according to the current transfer function curve,the transformer winding deformation is judged.Combined with the actual transformer modeling and simulation and off-line detection method,the 110 k V transformer winding deformation detection system is designed.The hardware system mainly includes signal source selection and injection module,protection module,signal acquisition module and data processing module.Development of transformer winding deformation detection system software based on LabVIEW platform.The software system includes data acquisition,data analysis and processing,and historical data query.In the laboratory,a test platform for the winding deformation of charged test is set up,and the test results are compared with the field test results,which verifies the effectiveness of the system.The system can quickly and accurately obtain the frequency response curve of transformer winding,and can effectively detect 110 k V large transformer winding deformation.The main factors which influence the measurement results are discussed through experiments and field measurements.The influence of load,length and position of the wire and the voltage amplitude of the signal source on the frequency response curves are analyzed.