Electric Propulsion systems based on HET thrusters are now the de facto standard for more than half of the GEO telecommunications and MEO navigation satellites launched each year, with Fakel's SPT-140d model representing the solution until early 2022 baseline for nearly all LSIs worldwide. This is due to its extreme reliability, the long heritage accumulated over the years, and the considerably lower selling price than the few existing competitors (Safran -France-, Aerojet and Busek -USA-). With the outbreak of war in Ukraine, all LSI found themselves in the need to find an alternative to Fakel's Hall effect thruster. As the only product that can be purchased on the western market together with Aerojet Rocketdyne's XR-5, from February 2022 Safran's PPS©5000 became the de facto new incumbent as it is not subject to ITAR restrictions. The F4F project aims at developing an alternative system, based on a different thruster, SITAEL’s HT5k, featuring magnetic shielding for very long life operations and able to be fed with both Xenon and Krypton. The TU will be coupled with an evolution of flight-proven Thales Belgium Mk3 PPU, the Mk3 EVO, and with an European solution for low pressure flow management from the German Company AST. The three subsystems will be modified to reduce complexity and limit at the bare minimum ITAR/EAR controlled items. Through a full coupling test, F4F will demonstrate performance at system level with the thruster unit operated with both xenon and krypton, and advance its TRL towards a full qualification.

Discrete GaN power electronic devices have penetrated the consumer market and first products have amply demonstrated a disruptive improvement of the performance and reduction of the form factor. With demonstrated robustness for heavy ion radiation and neutron radiation, p-GaN enhancement mode HEMTs allow disruptive innovative designs for space applications. However, to unlock the full potential of the technology for point of load convertors, three important limitations need to be solved, as addressed in this project, i.e. 1) the reduction of the inductive parasitics through monolithic integration of drivers and power devices (GaN-IC) 2) optimization of the inductive passive components together with the active devices 3) a strong interaction between point of load convertor design and GaN-IC design. Electrical performance and radiation robustness will be evaluated and assessed for space applications in the upcoming frame of satellites massive digitalization. The project with duration of 36 months, comprises of two learning cycles in definition and refinement of the application requirements, design and manufacturing of the GaN-ICs and passive devices, and development of the point of load convertor boards, first with focus on the basic building blocks and initial prototypes, followed by further optimization towards the target requirements. The consortium has been joined by Thales Alenia Space (France and Belgium) and Würth Elektronik as space and terrestrial point of load convertor manufacturers. IMEC contributes with its state-of-art GaN-IC platform technology and Würth Elektronik with the design and prototype manufacturing of the passives. MinDCet designs the optimized GaN-ICs and contributes with a state-of-art controller. This project contributes to EU non-dependence of GaN technology as discrete GaN transistors are, so far, mostly produced by Asian and/or North American manufacturers and pushes the state-of-the-art with higher level of integration (GaN-IC).

The main objective of the HV-EPSA project is to break the current state-of-the-art in satellite electrical & power subsystem, expand the present application domain of the classical technologies and perform a full system analysis and validation to optimize the electrical chain including the new electrical propulsion units and communication systems The electrical & power subsystem (EPS) is mainly devoted to provide electrical power to all the active systems of a satellite. It generates and distributes a “primary power bus” whose characteristics are optimized to the mission needs. This bus is usually generated from solar arrays and electrochemical batteries. These power sources are controlled by a Power Conditioning Unit (PCU) which delivers the power bus. EPS is a major constituent of a satellite : its cost may reach up to 30% of the total platform cost. There is a large design variety of power buses, with voltage levels typically ranging from 28 to 100V. This state-of-the-art is well adapted to past and current needs in term of power conditioning & distribution for science and telecommunication satellites. Nevertheless, a short-term need is raising for higher operating voltages, especially for the new electrical propulsion systems and high power payloads Increasing the bus voltage represents a real technical challenge. During its life, the satellite has to face many “harsh” environment constraints (radiations, pressure, plasma,…) which limit the choice of high voltage electronic parts and favor destructive electrical discharges or arcs. This study will consider: solar arrays, power conditioning and distribution units (PCDU), cables and connectors, up to the main driving units for high voltage feeds: the EPCs (Electrical Power Conditioner for radio frequency amplifiers supply) and PPUs (Plasma Propulsion Unit for electric thrusters). This study will enable a full system analysis including units optimization and materials testing within representative environment.

MINOTOR’s strategic objective is to demonstrate the feasibility of the ECRA technology as a disruptive game-changer in electric propulsion, and to prepare roadmaps paving the way for the 2nd EPIC call, in close alignment with the overall SRC-EPIC strategy. Based on electron cyclotron resonance (ECR) as the sole ionization and acceleration process, ECRA is a cathodeless thruster with magnetic nozzle, allowing thrust vectoring. It has a considerable advantage in terms of global system cost, where a reduction of at least a factor of 2 is expected, and reliability compared to mature technologies. It is also scalable and can potentially be considered for all electric propulsion applications, from microsatellites to space tugs. Although the first results obtained with ECRA have been encouraging, the complexity of the physics at play has been an obstacle for the understanding and development of the technology. Thus an in-depth numerical and experimental investigation plan has been devised for the project, in order to bring the technology from TRL3 to TRL5. The strong consortium is composed of academic experts to perform the research activities on ECRA, including alternative propellants, along with experienced industrial partners to quantify its disruptive advantages on the propulsion subsystem and its market positioning. ECRA’s advantages as an electric thruster technology can be a disruptive force in a mostly cost-driven satellite market. It would increase European competitiveness, help develop low-cost satellite missions such as constellations, provide end-of-life propulsion, and pave the way for future emerging electric propulsion technologies. The 36 months MINOTOR project requests a total EC grant of 1 485 809 M€ for an experienced consortium of 7 partners from 4 countries: ONERA (FR, Coordinator), industries Thales Alenia Space (BE), Thales Microelectronics (FR), SNECMA (FR), Universities Carlos III (ES) and Giessen (GE), and SME L-up (FR).

The European Direct-Drive Architecture (EDDA) project aims at optimizing the power chain efficiency of a spacecraft using electric propulsion, which is at the heart of technological roadmaps for future spacecraft. The objective is to develop, build and test a demonstrator of a high voltage and high power direct-drive concept. This innovative architecture supplies directly electric thrusters by a 300V-400V Solar Array without power conversion vs 28-100V in the current state of the art. The advantages are to remove power converters, to save mass, dissipation and cost, and to improve significantly the overall efficiency and reduce the thermal dissipation. In addition, at satellite level, it corresponds to a reduction of thrust duration, saving mission time. The ability of the concept to be applied to various thrusters technologies is key to maximize the impact of the architecture. Therefore this study is based on a transversal aspect of Electric Propulsion to be demonstrated on two different Electric Thruster technologies: Hall Effect Thruster (HET) from Sitael (Italy) and High Efficiency Multistage Plasma Thruster (HEMPT) from Thales-D (Germany). EDDA demonstration is based on a thruster plasma analysis (UC3M, Spain). Cathod Reference Point electronics, HET, vacuum chamber for complete testing are provided by Sitael. The bus voltage control loop and associated hardware are designed and manufactured by TAS-B. Coordination at satellite level is performed by TAS-F. Efficient Innovation provides effective management and associated tools. Tests will follow real operational conditions: no Sun, variation of illumination, thruster start-up and switch off, quick variation of consumption, and will demonstrate the robustness of this architecture easily adaptable to spacecraft (telecommunication satellites for Electric Orbit Raising reduction, In Orbit Servicing and Space-tugs, interplanetary carriers).