Influence of sinusoidal and square voltages on partial discharge inception in geometries with point‐like termination. Issue 1 (1st March 2018) - Abdelmalik, Abdelghaffar A.
Abstract : High‐voltage equipment involves both electrical and electronic components. In electrical power network, which consists of rotating machine, power transformers and transmission lines, field enhancement at critical regions can lead to local breakdown [partial discharges (PD)]. The continuous occurrence of PDs can lead to complete breakdown. While in large power equipment sharp edges can be avoided, this is not the case in power converter due to the miniature nature of the semiconductor device. Sharp edges can also be present in any power equipment in the shape of conducting particles, either stuck at a barrier or freely moving in the bulk oil. This creates high‐field regions, prone to PD activities. Different power equipment operates at different voltages such as AC, DC, square voltage, pulse voltage, fast‐rise transient voltage etc. This study presents the influence of sinusoidal voltage, slow‐ and fast‐rise square voltage on PDs in two different geometries using optical PD measurement technique. Fast‐rise square voltage has the lowest PD inception voltage while the sinusoidal voltage has the highest. This is may be due to the influence of homo‐ and hetero‐charges. Fast‐rise square voltage displayed higher PD magnitude at inception which may be connected to the rise time of the voltage.