Analysis of Partial Discharge Due to Movement of Spherical Particle in Power Transformer Using Computational Fluid Dynamics

Power transformer is costly and very important equipment in power sector. Failure of power transformer causes colossal damage to the power system. One of the important reasons for transformer failure is event of Partial Discharge (PD) in the transformer. Numbers of non-conducting and conducting particle are available in the transformer. Conducting particles available in the transformer or mineral oil entering into winding space, strike the energized winding of the transformer cause PD to occur. Movement pattern of particle administrates the probability of particle striking the winding. Analysis of movement of particles proximate to HV winding helps in understanding the occurrence of PD. This paper deals with tracking of aluminum and copper particles of various sizes available inside the transformer.

Experimental Study on the Movement of Conducting Spheroidal Particles under Electric Field in Air

Study on the movement of conducting particle is useful for managing particles in gas insulation systems. The authors observed the movement of conducting prolate spheroidal particles under uniform electric field in air. From the experimental results we found three patterns of the movement. The critical electric field results in particle rotating or lifting. The particles rotated about the contact point before lifting in most cases. The measured particle-rotating field was lower than the analytical ones by 6 and 21% for 9 and 18 mm gaps, respectively. From the experiment, the size of the particles and the gap distance affect the critical field. The voltage polarity has no effect on the critical field for particle movement because of little difference between the experimental values of positive and negative polarities.