In this paper, we performed an insulation diagnosis technique for oil-immersed power transformers by an acoustic detection method. Electrode system such as needle to plane electrode was fabricated to simulate a defect of power transformers. In addition, the frequency spectrum of acoustic signals with partial discharge (PD) in insulating oil was analyzed. From the FFT result, the frequency spect...

power transformers are key components in electrical power supplies and their failure could cause severe consequences on continuity of service and also generates substantial costs. identifying problems at an early stage, before catastrophic failure occurs, is a great benefit for reliable operation of power transformers. frequency response analysis (fra) is a new, well-known and powerful diagnost...

This paper presents a detailed review of the streaming electrification phenomena different insulating fluids for power transformers. The comparison techniques used to assess charging tendency is discussed depending on flow type (planar or centrifugal), volume oil, and interface material. charge separation between fluid metallic/pressboard interfaces explained in terms electrical double layer fo...

Power transformers in service are subjected to a wide variety of electrical, mechanical and thermal stresses capable of producing insulation faults. This type of failure figures amongst the most costly faults in distribution networks since it produces both machine outage and electrical supply interruption. Major research effort has therefore focused on the early detection of faults in the insul...

Static secondary ion mass spectrometry was used to study the corrosion inhibitor Irgamet®39 on the surface of copper treated in insulating oils and the effect of temperature changes, by means of temperature programmed desorption experiments under vacuum, on metal coverage. Four commercial oils, both corrosive and noncorrosive, showed no significant influence on the stability of the tolyltriazol...

Abstract Oil-impregnated paper is the most widely used insulating material for power transformers. Power transformers inevitably generate a lot of heat during operation. Among them, thermal aging one main forms paper. In this study, ab initio molecular dynamics method based on density functional theory to simulate cracking mechanism cellobiose under transient high temperature. The results show ...

The immersed-oil power transformer is so vital equipment in power system that maintenanceengineers take more monitor from transformer’s insulating oil to diagnose what is condition of operation. Then the dissolved gas analysis (DGA) is known for an effective technique on detecting incipient faults in oil-immersed power transformers. In this paper, a practical method is presented which consists ...

Power transformers are key components in electrical power supplies and their failure could cause severe consequences on continuity of service and also generates substantial costs. Identifying problems at an early stage, before catastrophic failure occurs, is a great benefit for reliable operation of power transformers. Frequency Response Analysis (FRA) is a new, well-known and powerful diagnost...

In this paper, Artificial Neural Networks are used to solve a complex problem concerning to power transformers and characterized by non-linearity and hard dynamic modeling. The operation conditions and integrity of a power transformer can be detected by analysis of physical-chemical and chromatographic isolating oil, allowing establish procedures for operating and maintaining the equipment. How...