Multi-mode discharge behaviour induced by charged micron-nano dust and photonic characterization

This study investigates the unique multi-mode discharge mechanisms induced by charged micron-nano dust in high-voltage systems, which exhibit distinct dynamic, electromagnetic, and statistical characteristics compared to larger particles. Existing detection technologie fail to capture the attenuated, highly concealed signals from micron-nano dust-induced weak discharges, hindering mechanistic understanding. To address this gap, we develop a novel ultraviolet-visible-infrared (UV-VIS-IR) multi-spectral detection platform using silicon photomultiplier (SiPM) tube arrays with high-transmittance bandpass filters. Experiments analyze dispersed micron-nano dust discharges preceding surface flashovers and air-gap breakdowns. Surface flashovers require micron-nano dust speckle formation and contour deepening, reducing system breakdown voltage by up to 71%. Dust arrangement critically influences flashover voltage. Discharge spectral intensity inversely correlates with particle size and increases with dust mass, with VIS (350-600 nm) being dominant. The work elucidates fundamental mechanisms of micron-nano dust-induced penetrating discharges, providing a foundation for advanced detection and mitigation strategies.