Authors:

David Rubin

Date Created:

Not specified

Course Title:

Professor:

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About Paper:

Hollow cathodes have long been used as the operation principle of neutralizers for electric propulsion but are expensive to replace if a failure occurs. Particularly in lab settings, they can be prone to poisoning which severely shortens their lifespan. This research seeks to propose a new system in place of the traditional hollow cathode neutralizer, operating with inductively coupled plasma to properly neutralize the thruster and allow steady operation. To evaluate this system, copper coils were wrapped around a glass tube and tested with varying parameters of power frequency and tube diameter. The system was connected to an external generator and amplifier and tested under high vacuum. Visual observations were collected about plume intensity and a bidirectional coupler was used in series to read the forward and reflected power. Initial measurements indicated that the neutralizer was generating enough power to adequately supply the thruster, but steady state running was not observed. It is believed that the voltage drop within the plasma was too high due to a small contact surface with the electrode. To overcome this, copper inserts were installed to extend the electrode contact area within the plasma. Similar visual results and power measurements were collected as the original design, but the new system allowed the thruster to achieve stable ignition and run for several seconds. This work tackles the issue of having reliable and easily replaceable neutralizers which will enable the operation of electric thrusters in lab settings. Keywords: Plasma; Electric Propulsion; Neutralizer; Hall-Effect Thruster; Radio Frequency

Source:

Purdue University / 2025

Topics:

No topics listed

Co-authors:

David Rubin