Thanks to their high efficiency, constantly increasing thrust levels, and achievable total impulses, electric satellite thrusters are becoming increasingly important in modern space propulsion systems. As a result of the ongoing miniaturization of electronic components and increasingly efficient manufacturing processes, electric propulsion systems are also becoming more and more interesting for very small satellites, e.g., CubeSats. Due to the low electrical power in the range of a few watts available in these satellites and the limited space in CubeSats, the thrusters used must have sufficient reliability and service life in addition to low power consumption and size. The pulsed vacuum arc thruster (VAT) is a promising type of thruster for CubeSats due to the simple design of the thruster head and the associated power electronics. VATs were first mentioned in the 1970s and have been explicitly investigated for use in CubeSats since the early 2000s. However, they are not yet ready for operational use, except for laboratory prototypes and technology demonstrators. The main reasons for this are the achievable pulse numbers of a few 100,000 pulses and the insufficient reliability of the ignition. Based on these limitations, the causes of this were investigated in this thesis, technical solutions were identified, and the HERVAT system was developed. The focus here was on a significant increase in the achievable pulse numbers to more than 10,000,000 pulses, with a pulse energy of ≤ 1 J, as well as maintaining the simplest possible design and a competitive thrust efficiency. For this purpose, a pulse generator system (PPD) was first developed, which covers all necessary ignition methods and thus ensures reliable operation. The required ignition method is selected automatically, without an additional control and regulation circuit, and adapts to the conditions at the engine head. In addition to high-voltage ignition, triggerless ignition and short-circuit ignition of the engine can also be carried out. The novel thruster head of the HERVAT system achieves more than 10,000,000 pulses by using a hollow cathode and an auxiliary anode without the need for a cathode feeding mechanism. The thrust measurements performed showed that the HERVAT system is competitive with other VAT systems, with a thrust efficiency of up to 3 µN W−1 when using a titanium cathode. The result of this work is a reliable and durable vacuum arc thruster, which can significantly influence the development of future pulsed vacuum arc thruster systems due to its simple design in combination with the high achievable pulse numbers.
«Thanks to their high efficiency, constantly increasing thrust levels, and achievable total impulses, electric satellite thrusters are becoming increasingly important in modern space propulsion systems. As a result of the ongoing miniaturization of electronic components and increasingly efficient manufacturing processes, electric propulsion systems are also becoming more and more interesting for very small satellites, e.g., CubeSats. Due to the low electrical power in the range of a few watts ava...
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