Relaxation studies to identify aging with oil filled transformers - analysis

Reliable condition indicating parameters are needed in the energy sector with Web based information structure and with increased number of aged power apparatus operating in digital switching and loading environment. This project for oil-filled power transformers is taken up by Cooperative Research Centre for Integrated Engineering Asset Management (CIEAM) to develop knowledge models for prediction of remaining life of operating transformers and for other asset decision making processes in prognosis of failure rate. The aims at Queensland University of Technology (QUT) are to come up with partial discharge (PD) and relaxation condition indicators. In this paper, analysis of the earlier paper results is presented to arrive at condition indicators for aging. The time domain results are analyzed with three techniques and frequency domain results are analyzed with four techniques based on the reported dielectric response models. The study yields new dynamic information on aged status to develop the multiple diagnostic models for the prediction of the remaining life, rate of degradation and developing faults.