Controlling azimuthal spoke modes in cylindrical Hall thruster using a segmented anode

TL;DR

This paper presents a method to actively control azimuthal spoke modes in cylindrical Hall thrusters by adjusting the segmented anode's boundary conditions, influencing plasma behavior and device performance.

Contribution

It introduces a novel active control technique for azimuthal modes in Hall thrusters using segmented anode voltage and phase adjustments.

Findings

Controlling azimuthal modes alters plasma properties.

Phase variation affects spoke mode characteristics.

Technique can induce or suppress azimuthal activity.

Abstract

Azimuthal spoke-like modes commonly occur in ExB discharges. The natural occurrence of the spoke mode is correlated with changes of plasma parameters. Here, instead of allowing these changes to occur naturally, we report a technique for actively controlling the spoke by adjusting the boundary condition at the anode. The technique is demonstrated using a cylindrical Hall thruster equipped with a segmented anode. By varying the voltage and the relative phases of the anode segments, properties of the azimuthal mode can be altered substantially, as shown by fast camera images and probe diagnostics. This technique may be extended to other Hall discharges in order to either induce or suppress azimuthal activities, and thereby controlling the operation and the performance of the devices.