Weibull Analysis Applications in Unexpected Electrical Breakdown of Ion Thruster

Abstract

The unexpected electrical breakdown (UEBD) of ion thruster is a critical problem. It directly affects the reliability and performance of the ion thruster. The basic UEBD characteristics and Weibull theory are introduced. The self-consistency and applicability of Weibull analysis for UEBD study are discussed. The UEBD period is a proper characteristic variable for Weibull analysis. The approaches to study the factors affecting the UEBD period are presented: (i) distinguishing the effect of coupled factors with the shape parameter of a mixed Weibull distribution, and (ii) studying the effect of a single factor with its respective parameters of the Weibull distribution. The factors discussed include electric field strength, grid material, and ion density. Further aspects to investigate involving the coupling of these factors and mechanisms are prospected.