Optimization of vacuum arc thruster efficiency through inductive energy storage circuit control

This study explores the optimization of vacuum arc thruster (VAT) performance through precise control of an inductive energy storage circuit. Two experimental approaches were investigated: (1) By varying the inductor charging time under single-pulse ignition, this experiment aims to determine the relationship between the circuit components and the performance of the VAT. (2) Implementing a dual-pulse ignition scheme with controlled inter-pulse delays, which aims to determine whether two ignitions interact with each other. In the single-pulse tests, maximum thrust performance occurred when the inductor current reached its peak. Reducing the charging current to approximately 76% of this peak resulted in decreases of 28%, 38%, and 42% in discharge energy, plasma plume, and mass ablation rate, respectively. These results demonstrate that VAT performance is strongly dependent on the energy stored in the inductor and the magnitude of the induced voltage generated upon IGBT turn-off. In the dual-pulse tests, triggering two identical inductive circuits with a 3 μs inter-pulse delay significantly enhanced performance. Compared to a 3000 μs delay, this shortest delay resulted in a 68.74% lower breakdown voltage for the second pulse, a 15.22% increase in total discharge energy, a 98.7% extension in discharge duration, and a 356% increase in the ablation rate. The highest thrust of 12.07 μN·s and thrust-to-power ratio of 29.97 μN·s/W were achieved at this shortest delay. These findings highlight that both induced voltage characteristics and short inter-pulse plasma dynamics play critical roles in maximizing VAT performance, offering practical insights for high-efficiency pulsed electric propulsion system design. • Inductive circuit control significantly enhances VAT performance. • Peak inductor current maximizes thrust and plasma generation. • Short dual-pulse delays reduce breakdown voltage by 68.7%. • Double-pulse ignition boosts thrust-to-power ratio up to 29.97 μN·s/W. • Findings provide design insights for efficient pulsed electric propulsion.