Ainhoa Galarza

Analysis of the Results of Accelerated Aging Tests in Insulated Gate Bipolar Transistors

The introduction of fully electric vehicles (FEVs) into the mainstream has raised concerns about the reliability of their electronic components such as IGBT. The great variability in IGBT failure times caused by the very different operating conditions experienced and the stochasticity of their degradation processes suggests the adoption of condition-based maintenance approaches. Thus, the development of methods for assessing their healthy state and predicting their remaining useful life (RUL) is of key importance. In this paper, we investigate the results of performing accelerated aging tests. Our objective is to discuss the design and the results of accelerated aging tests performed on three different IGBT types within the electrical powertrain health monitoring for increased safety (HEMIS) of FEVs European Community project. During the tests, several electric signals were measured in different operating conditions. The results show that the case temperature (TC), the collector current (IC), and the collector-emitter voltage (VCE) are the failure precursor parameters that can be used for the development of a prognostic and health monitoring (PHM) system for FEV IGBTs and other medium-power switching supplies.

Identification of the degradation state for condition-based maintenance of insulated gate bipolar transistors: A self-organizing map approach

Abstract This paper presents an approach for the detection of the degradation onset and the identification of the degradation state of industrial components with inhomogeneous degradation behaviors due to the effects of multiple, possibly competing, degradation mechanisms and non-stationary operational and environmental conditions. The novelty of the approach is the use of dedicated Self-Organizing Maps (one for each component): each Self-Organizing Map is trained using data describing the component healthy behavior and a degradation indicator is defined by the distance between the test measurement and the Self-Organizing Map best matching unit. A case study regarding Insulated Gate Bipolar Transistors used in Fully Electrical Vehicles is considered. Data collected in experimental accelerated aging tests are used. The proposed approach is shown able to detect the initiation of the Insulated Gate Bipolar Transistors degradation process and to anticipate the component failure.

Online indirect measurement of ESR and capacity for PHM of capacitors

This paper shows a system to measure the Equivalent Series Resistance (ESR) and Capacitance (C) of capacitors. This system provides a cost effective solution for Prognostic Health Monitoring (PHM) of capacitors used in fully electric vehicles (FEV) and medium-power switching supplies. The system is based on a Hartley resonant topology formed by two inductors and a variable capacitor. This circuit is able to measure Metalized Thin Film Capacitors (MTFC) as well as electrolytic capacitors. The paper analyzes the circuit and compares the results of simulations and experiments.

HEMIS Project (Electrical Powertrain HEalth Monitoring for Increased Safety of FEVs): Limitations of Electromagnetic Standards for Vehicles Equipped with Electrical Powertrain

The HEMIS project is concerned with health monitoring of electrical powertrain in order to enhance the maintainability and safety of electric vehicles. Electromagnetic emissions from electrical powertrain will change the electromagnetic environment in vehicles, which may have implications for electromagnetic compatibility and, because of the high electrical power levels, human exposure to electromagnetic fields. This paper outlines some of the electromagnetic issues under investigation in the project, including limitations of existing test methods for electromagnetic compatibility, and a lack of test methods for the assessment of in-vehicle human exposure, as well as for both electromagnetic compatibility and human field exposure issues relating to wireless charging of traction batteries.