Electroacoustic characteristics of short gap suspended electrode discharge

The discharge and breakdown behavior of air gaps under high-voltage excitation critically informs the design of external insulation in power transmission and transformation systems. Unlike single-gap configurations, composite gaps containing suspended conductors exhibit complex interactions: the floating conductor alters the spatial field distribution, and when one sub-gap undergoes breakdown, its charge injection or pilot streamer development modulates the conductor’s potential, thereby influencing the discharge dynamics of adjacent sub-gaps. In this work, we systematically investigate the electroacoustic response of short air gaps augmented with suspended electrodes. Time-domain waveforms of the acoustic emissions are captured throughout the entire discharge process for varying suspended-electrode positions. Our analysis reveals that the inclusion of a suspended electrode accelerates the acoustic decay, elevates the dominant oscillation frequency, and reduces the waveform amplitude. Moreover, as the suspended electrode is moved closer to the anode, the primary frequency further increases, the amplitude diminishes, and the acoustic attenuation accelerates. These findings advance the fundamental understanding of multi-gap discharge mechanisms and suggest novel diagnostic metrics for plasma–acoustic interactions in complex insulating geometries.