Prognostic models should properly take into account the effects of operating conditions on the degradation process and on the signal measurements used for monitoring. In this paper, we develop a particle filter-based (PF) prognostic model for the estimation of the remaining useful life (RUL) of aluminum electrolytic capacitors used in electrical automotive drives, whose operation is characterized by continuously varying conditions. The capacitor degradation process, which remarkably depends on the temperature experienced by the component, is typically monitored by observing the capacitor equivalent series resistance (ESR). However, the ESR measurement is influenced by the temperature at which the measurement is performed, which changes depending on the operating conditions. To address this problem, we introduce a novel degradation indicator independent from the measurement temperature. Such indicator can, then, be used for the prediction of the capacitor degradation and its RUL. For this, we develop a particle filter prognostic model, whose performance is verified on data collected in simulated and experimental degradation tests

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

This study presents the analysis and design of a novel technique that improves the efficiency of the conventional forward DC-DC converter by reducing switching losses, along with a comprehensive analysis of the circuit and detailed information for designers. The converter uses the current control mode to trigger the switches. To use this control mode, an equalising circuit is presented in the input port to guarantee that the voltage in each half-switching period will be equal; otherwise, the current control mode cannot be applied. A 5 kW step-down (from 350-500 to 28.8 V) prototype is presented and compared with the traditional hard-switching forward converter for fully electric vehicle applications. In addition, the small-signal characteristics and the dynamic response for load variation are presented. Efficiency improvements of over 2% are obtained.

No abstract