Investigations on dielectric and partial discharge properties of nano SiO2 modified FR3 transformer oil

Abstract

Electrical energy is the prime source of life for day to day activitie In order to meet the periodically increasing electric power demand electrical utilities are developing ultra high voltage power transmission lines In India power transmission at 400 kV AC is now upgraded to 765 kV AC system Very soon electrical utilities are planning to run the power transmission system at 1200 kV ultra high voltage level The major benefits of electric power transmission at ultra high voltages are increase in voltage reduces the current carrying limit of conductors and hence sizes of the conductors are reduced This also leads to decrease in losses which results in improved efficiency Since the current flow in transmission line is reduced it results in less voltage drop and hence it improves voltage regulation Considering these facts in the present work lightning impulse withstand and breakdown characteristics lightning impulse streamer propagation velocity characteristics partial discharge characteristics breakdown strength characteristic tan delta characteristics and volume resistivity characteristics of nanofluid insulation prepared with base FR3 oil and nano SiO2 fillers at different wt concentrations were evaluated in the laboratory at different electrode configurations and at different test conditions. Results show that addition of SiO2nanofillers certainly improves the dielectric characteristics of FR3 oil significantly and hence these test results will be very much useful for electrical utilities for developing better condition monitoring system for power transformers filled with nanofluids newline