This paper investigates the reliability of an isolated buck-boost DC-DC converter (IBBC) based on the configuration of a series resonant converter (SRC). Two approaches are employed to predict the IBBC reliability, which are based on the MIL-HDBK-217F handbook and FIDES guide. The latter approach can take into account how the failure rate of the converter components based on the physics of failure is influenced by a varying yearly mission profile. To do this, the thermal loading of each IBBC component is obtained, taking into account the photovoltaic (PV) mission profile of the solar irradiance and ambient temperature. In such a case, the PV module is operating at the maximum power point (MPP) and the IBBC transfers this power into the DC microgrid (MG). Second, the component-level failure rate is calculated with both reliability assessment approaches, to evaluate the converter-level failure rate. Therefore, the converter reliability can be defined while taking the serial reliability connection of the converter components into account. The reliability analysis is carried out using a cloud Python engine installed and running in a Google Colaboratory notebook. The results indicate that the primary semiconductors are the most vulnerable component in the IBBC. The B10B_{10} lifetime of the case-study IBBC calculated using the MIL-HDBK-217F and FIDES approaches is 14.80 and 23.20 years, respectively. This indicates that, when compared to the methodology from the MIL-HDBK-217F handbook, the approach from the FIDES guide can provide a more accurate prediction for the IBBC lifespan considering the real field mission profile.

中文翻译：

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隔离式升降压DC-DC串联谐振变换器的可靠性评估


本文研究了基于串联谐振转换器 (SRC) 配置的隔离式降压升压 DC-DC 转换器 (IBBC) 的可靠性。采用两种方法来预测 IBBC 可靠性，这些方法基于 MIL-HDBK-217F 手册和 FIDES 指南。后一种方法可以考虑基于故障物理原理的转换器组件的故障率如何受到变化的年度任务概况的影响。为此，需要考虑太阳辐照度和环境温度的光伏 (PV) 任务曲线，获得每个 IBBC 组件的热负荷。在这种情况下，光伏模块在最大功率点（MPP）运行，IBBC 将此功率传输到直流微电网（MG）。其次，通过两种可靠性评估方法计算组件级故障率，以评估转换器级故障率。因此，可以在考虑转换器组件的串联可靠性连接的同时定义转换器可靠性。可靠性分析是使用安装在 Google Colaboratory 笔记本中并运行的云 Python 引擎进行的。结果表明，初级半导体是 IBBC 中最脆弱的组件。使用 MIL-HDBK-217F 和 FIDES 方法计算的案例研究 IBBC 的 B10B_{10} 寿命分别为 14.80 和 23.20 年。这表明，与 MIL-HDBK-217F 手册中的方法相比，FIDES 指南中的方法可以在考虑实际现场任务概况的情况下为 IBBC 寿命提供更准确的预测。