The current medium power PPS®5000 thruster unit which equips several satellites uses xenon as its propellant. However due to a sharp rise in costs and an emerging shortage of xenon, significant impacts on the economics of certain future mission profiles such as those planned for the replacement of current geostationary (GEO) telecommunication satellites are expected. It is thus necessary to seek alternative more abundant and cheaper propellant alternatives such as krypton. However, today there is no European thruster available on the market in the range 2.5 to 5 kW qualified to be used with krypton. The replacement of xenon by krypton would normally require a full qualification comprising many hours years of ground testing to be performed prior to obtain the ‘ready for flight’ status as required by the current ECSS standards. This full qualification serves to provide a high level of confidence in the thrusters operational abilities but it is a timely and costly process. INVICTUS proposes to implement a delta-qualification approach to extend the qualification status of an established electrical propulsion system. The successful acceptance of this approach by the satellite integrator and operators, will be an important stepping stone to help future programs towards a clear evolution in the ECSS standards. It will also be possible to generalize this approach to changes not only limited to propellant or cathode emitter material, but will help address other future potential modifications driven by innovation such as changes in discharge chamber wall material or electro-magnet coils settings. By the end of project, the PPS ®5000 will be ready for flight (TRL8) using krypton, a worldwide first-of-a-kind based on two delta qualifications exercises (xenon to krypton with the necessary adaptations to the fluidic regulator and PPU NG2, and a change from an Asian to an EU supplier for the Cathode emitter) allowing the deployment of these thruster units by 2026.

Faced with the increasing demands of satellite contractors in terms of costs and mission capabilities, the EU’s space sector must be ready to react as quickly as possible to the needs related to the evolution of space infrastructures and markets to stand out from the competition at global level. Electric Propulsion (EP), based on Hall-Effect Thruster (HET), is strategic to foster the EU’s space sector competitiveness. Europe needs competitive EP Systems or EPS (combination of a Power Processing Unit (PPU) driving and delivering electrical power to a HET). The PPU has a strong impact on the EPS cost and performances. Completed in 2021, the H2020 GaNOMIC project demonstrated the feasibility of major disruptive technologies for the PPU. A PPU based on these technologies will open the way to extend drastically the mission field capability and efficiency of EPS, pushing propulsion systems to an unprecedented level of competitiveness, capability, and efficiency. To achieve these impacts, ECOPROPU, takes over from GaNOMIC and will develop five key generic Building Blocks for the PPU which are crucial to unlock the target performances of the EPS: three functions of the PPU (Anode module, Digital processing module, Magnet power converter) and two other Building Blocks on which the Anode module rely (DAB digital controller and Planar transformer). ECOPROPU will also prepare and evaluate the HET adaptation to high voltage operation brought by this innovative PPU by better understanding stability and magnet-related phenomena and a complete operation mapping of a large domain thruster (2-7kW, 250-700V operating domain). The impact of this project will be to give the consortium industry the capacity by 2025 to develop disruptive and economic PPU and versatile EPS (medium to high power class), allowing to reach a European worldwide leadership in EPS and offer to European space primes and agencies improved performances and cost reduction for their space missions.

For the future of space exploration and space logistics, and to reduce costs for orbit transportation of future payloads, very high-power Hall Effect thrusters of 20 kW or above are at the forefront of several initiatives today. Be it as single or clustered units, the combined thrust of these electric propulsion systems (EPS) paves the way to allowing larger spacecraft and more ambitious missions to be envisaged. However, given that these missions would require significant burn time of the EPS, several important issues must be addressed that go beyond the simple ability of manufacturing larger EPS components. Specifically, qualifying such electric thrusters for lifetime is currently a showstopper. In the race to the Moon and Mars, as well as other lucrative commercial missions within earths orbit beyond 2030, the European Space industry must catch up with the US. Studies within Europe have already been initiated for the incremental development of 20-kW class Hall thrusters such as the FP7 HiPER project which produced the PPS20k ML thruster up to TRL4, FP7 CHEOPS project which permitted SITAEL to develop their 20kW HET, ESA projects allowing UNIPI to develop their nested multi-channel TANDEM thruster or the ongoing H2020 ASPIRE project led by SITAEL. Nevertheless, given the challenges and the opportunities that VHP present, research such as proposed in CHEOPS-VHP-BB must be anticipated now ahead of its effective deployment in 2030-40. Project activities will complement ongoing thruster-focused development activities with research and development on key building blocks essential for the future use of VHP Hall thruster systems: overall system architecture against various mission use cases, robust and cost-effective approach to qualification using Probabilistic Failure Analysis, manufacturability of key components subject to wear, notably the discharge chamber and cathode and the ability to envisage alternative propellants and power sources for future missions.

HEMPT-NG addresses the topic COMPET-3-2016-a on Incremental Technologies part of the SRC electrical propulsion in line with the EPIC roadmap “to increase the competitiveness of EP systems developed in Europe” by developing an integrated solution based on HEMPT (Highly Efficient Multistage Plasma Thruster) , the fluidic management system, and the power processing unit. The proposed development will raise the performance of all components beyond current state-of-the-art. The results will offer an ideal EPS system for LEO application up to 700 W and for Telecom/Navigation application up 5 kW. The HEMPT technology offers unique innovative features compared to other EP technologies and makes HEMP a key candidate to overcome all the currently identified deficiencies: 1. No discharge channel erosion leading to higher lifetimes of the thruster, 2. Acceleration voltages enabling a high specific Impulse (ISP) leading to a drastic reduction of propellant consumption, 3. Unique large range of thrust offer enormous flexibility, 4. Minimal complexity of concept providing an excellent basis for economic competitiveness. The HEMPT-NG consortium is led by TES (Thales Electronic System GmbH), subsidiary of the Thales Group, worldwide leader in the development and production of space products, responsible for thruster equipment and integrated EPS. European industrial partners are: Thales, OHB, Airbus and Aerospazio, who bring their expertise in spacecraft mission studies, equipment development and testing capacities. The University of Greifswald will provide plasma simulation to support the thrusters developed. These eight partners in five European member-states (Germany, France, UK, Belgium, Italy) will develop an economical and well-performing HEMPT LEO and GEO EPS to guarantee European leadership and competitiveness, as well as the non-dependence of European capabilities in electric propulsion. This proposal falls under the CONFIDENTIALITY rules described in Section 5.

To prepare future large satellite missions, replace obsolete networks or introduce new on-board technological advances, Europe must offer to its satellite industry a competitive and highly reliable European dual mode Hall-effect Electric Propulsion System able to provide sufficient power to perform both orbit raising (7kW) and station keeping (3kW) duties. Based on CHEOPS Phase I results, CHEOPS MEDIUM POWER will perform incremental developments on system and sub-system levels in order to achieve TRL6/7 by 2025. CHEOPS MEDIUM POWER will further mature the different system elements (Thruster Unit, PPU, FMS) by addressing the following key challenges: non-recurring and recurring cost reduction in terms of design, manufacturing, test qualification and time to deliver, as well as propellent efficiency in order to increase valuable payload and generate revenues. These advancements will fit into a less than 10kg thruster working between 300 and 450V. CHEOPS MEDIUM POWER will deliver for the thruster unit an optimised design for a very high thrust and improved lifecycle durations. On an industrial level the project aims at reduced fabrication cycles, improved quality, leaner manufacture, faster assembly lead times, and improved tolerance management. The Power processing unit will be optimised by removing unnecessary functions and re-selecting cheaper key components with at least constant reliability levels. The project’s scope extends to FMS level where space qualifiable COTS will be used to provide maximum mission suitability for variable number of thrusters per satellite. CHEOPS MEDIUM POWER will have a medium-term impact on the European space industry and its overall competitiveness, but also on the satellite design and manufacturing paradigm in the long term.