Electrical Characterization under Harsh Environment of DC-DC Converters used in Diagnostic Systems

In several applications (e.g. industrial plants, energy production systems, pipelines, offshore plants, wind turbines, etc) the DC-DC converter must endure harsh environmental and operating conditions. Stress as temperature, humidity, mechanical shocks and vibrations deeply affect the converter from both performance and reliability points of view. However, recent literature misses to consider a characterization of the DC-DC convert performances in presence of harsh operating environment with considerable stress levels. Trying to solve these needs, this paper presents a customized Reliability Stress Screening (RSS) test plan that includes high temperature, low temperature, high humidity and wideband vibration to characterize the electrical performances of an innovative DC-DC converter used in diagnostic systems for condition monitoring of industrial plants. The converter presented in this work has been driven using the Pulse Skipping Modulation (PSM) in spite of the well-known Pulse Width Modulation (PWM) in order to increase the conversion efficiency and the autonomy of the node. The test plan has been performed on a set of eight customized DC-DC converters to ensure significant and reliable results. The aim of this characterization under harsh environments is to propose a robust and reliable DC-DC converter that could be installed in different operating environments ensuring its proper expected performances. The measurement results highlight the stability of the proposed converter in terms of efficiency, input ripple, output ripple, step response and reliability. One of the most striking results highlighted in the manuscript is that the benefits of PSM with respect to the PWM in case of light load conditions are even more remarkable in presence of harsh environment.