Voltage-time Characteristics of the Different Cellulose Particle Content Transformer Oil in A Highly Nonuniform Field under Lightning Impulse

In this work, experimental study on the voltage-time characteristics of the different cellulose particle content transformer oil in a highly non-uniform field under lightning impulse is conducted. The standard lightning impulse (SLI) wave and the oscillating lightning impulse (OLI) wave are selected as the applied impulse voltage wave. The test results show that the increase of the cellulose particle content directly affects the voltage-time characteristics of the transformer oil, which manifests as an obvious decrease of the breakdown voltage. At the same particle content, under OLI the oil breakdown voltage is higher and the breakdown time lag is longer compared with the data under SLI. This research is helpful to deepen the understanding of the effect of the cellulose particles and the impulse waveform oscillation on the oil breakdown, and can provide experimental support for the onsite withstand voltage test.