Disruptive Power Processing Unit (PPU) for Electrical Propulsion Gridded Ion Thrusters

Electrical propulsion technologies can be broadly classified into several categories, each of which relies on different principles and techniques. Some of the most important technologies in electrical propulsion include:

• Ion Thrusters: Ion thrusters use an electric field to accelerate ions (typically noble gases such as xenon) to produce thrust. They are highly efficient and have a high specific impulse, making them well-suited for long-duration missions.
• Hall Effect Thrusters: Hall effect thrusters use a magnetic field to confinement a plasma and accelerate ions to produce thrust. They are similar to ion thrusters in terms of performance, but are generally smaller and less complex, making them well-suited for smaller spacecraft.
• Gridded Ion Thrusters: Gridded ion thrusters are a type of ion thruster that use grids to control the acceleration of ions, leading to higher thrust and efficiency compared to traditional ion thrusters.

The most common fuel used in electrical propulsion systems is a propellant, typically a noble gas such as xenon, krypton, or argon. These gases are ionized by an electric field and accelerated by the thruster to produce thrust. The use of a noble gas as a propellant has several advantages, including:

• High atomic mass: Noble gases have a high atomic mass, which makes them ideal for ionization and acceleration, as they provide a high specific impulse.
• High energy density: Noble gases have a high energy density, meaning they can store a large amount of energy in a small volume, making them well-suited for use in electrical propulsion systems.
• Low toxicity: Noble gases are relatively safe and non-toxic, making them a good choice for use in spacecraft where human health and safety is a concern.
• Low affinity with other atoms: No chemical recombination with other atoms and no oxidizing impact.
• Long shelf life: Noble gases have a long shelf life, meaning they can be stored for long periods of time without degradation.

The most common fuel used in electrical propulsion systems is a propellant, typically a noble gas such as xenon, krypton, or argon. These gases are ionized by an electric field and accelerated by the thruster to produce thrust. The use of a noble gas as a propellant has several advantages, including:

• High atomic mass: Noble gases have a high atomic mass, which makes them ideal for ionization and acceleration, as they provide a high specific impulse.
• High energy density: Noble gases have a high energy density, meaning they can store a large amount of energy in a small volume, making them well-suited for use in electrical propulsion systems.
• Low toxicity: Noble gases are relatively safe and non-toxic, making them a good choice for use in spacecraft where human health and safety is a concern.
• Low affinity with other atoms: No chemical recombination with other atoms and no oxidizing impact.
• Long shelf life: Noble gases have a long shelf life, meaning they can be stored for long periods of time without degradation.

The Power Processing Unit (PPU) in a gridded ion electric propulsion system is responsible for converting electrical power from the spacecraft into the high voltage required to operate the Gridded ion thruster. The PPU typically performs several key functions, including:

• Power conversion: The PPU converts the electrical power from the spacecraft into the high voltage required to ionize the propellant and accelerate the ions.
• Power regulation: The PPU regulates the voltage supplied to the thruster to ensure consistent and stable operation.
• Power conditioning: The PPU conditions the electrical power to remove ripple or noise in a certain bandwidth, which could impact the operation and the stability of the thruster.
• Thruster control: The PPU reads useful telemetries and provides the necessary control signals to the thruster, such as pulse-width modulation and frequency control, current or voltage sources, to regulate ionization, and the neutralizer (also called cathode).
• Safety features: The PPU also includes safety features, such as over-current over-voltage and over-temperature protection, to ensure that the thruster and spacecraft are protected from any damage in the event of a failure.

PPU is a critical component of a gridded ion electric propulsion system, as it converts the electrical power from the spacecraft into the high voltage required to operate the thruster. By providing consistent, stable, and well-conditioned electrical power, the PPU helps to ensure reliable and efficient operation of the thruster.

• High voltage requirements are more demanding: Gridded ion thrusters require high voltage to ionize the propellant and accelerate the ions to produce thrust. Generating and regulating high voltage power is a complex and challenging task, which requires specialized components and careful design.
• Strict safety requirements: The high voltage and high power used in gridded ion thrusters pose safety risks to the spacecraft and its crew. The PPU must include safety features to prevent electrical faults and protect the spacecraft from damage. This can add to the complexity to the PPU.
• GIT technologies require more power sources than HET technology: while HET technology requires only to power and control a Thruster grid, the GIT technology requires multiple power sources to power and control different grids and auxiliary units.

Developing a medium-power processing unit (PPU) in Europe is important for several reasons, including:

• Space independence: By developing its own capabilities in PPUs, Europe can become more independent in its space capabilities and reduce its reliance on other countries and regions.
• Technology advancement: Developing a medium-power PPU can drive technological advancements and innovation in Europe, which can lead to the development of new products, services, and applications.
• Competitive advantage: Developing a medium-power PPU in Europe can give European companies a competitive advantage in the global market for electrical propulsion systems, which is a growing market with significant potential for growth.