Experimental Investigation of Arc Characteristics Between Piezoelectrically Actuated Contacts in Air, Vacuum, and Nitrogen

Piezoelectric actuators enable ultra-fast switching due to their microsecond-scale response and high acceleration capability. This study experimentally investigates arc behavior in air, vacuum, and nitrogen using round and flat contacts driven by an amplified piezoelectric actuator. Unlike prior work focused mainly on actuation dynamics, this study provides a multi-medium comparison and investigates the coupled effects of drive operating time and contact geometry on arc characteristics. Arc tests were conducted using a capacitor discharge platform, with synchronized electrical measurements and high-speed imaging. In air (140 V, 350 A), arc voltage increased with rise time, reaching 800 V, 840 V, and 1080 V at 0.5 ms, 1 ms, and 2 ms, respectively, while shorter rise times reduced arc duration but promoted reignition. In vacuum (140–200 V), arc voltage stabilized at 80–90 V, with longer rise times extending arc duration; round contacts exhibited faster voltage rise and higher peaks. In nitrogen (140–200 V), higher voltages were obtained at shorter rise times, reaching 2680 V, 2600 V, and 2320 V at 0.5 ms, 1 ms, and 2 ms, respectively, with reduced arc duration. Across all media, round contacts consistently produced higher arc voltages than flat contacts. These results demonstrate that drive dynamics and contact geometry critically influence arc voltage and duration, providing practical guidelines for the design of high-speed piezoelectric-based switching devices.