DSP Oscilloscope for HVDC Fault Testing System

Due to frequently occurring vacuum sparking in the accelerators, snubber is used to limit the fault arc current to improve the International Thermonuclear Experimental Reactor safety. In this paper, a two-channel impulse automatic digital oscilloscope, based on field programmable gate array and digital signal processing (DSP), is designed to automatically measure fault arc current and voltage which exist in snubber-implemented high voltage direct current (HVDC) circuit whose fault can destroy many crucial components of the magnetic confinement fusion device. Experimental results from both 12 V low voltage direct current and 120 kV HVDC show that this DSP oscilloscope is stable, reliable, fully automatic, and can function well under strong electromagnetic interference conditions, which fully meet the experimental requirements.