Analysis of Capacitor Parameters Signature Variation with Ageing in Critical Healthcare Power Management Systems

Medical engineering applications have brought more stringent requirements in the reliability of critical power electronics healthcare monitoring systems. Medical electronics devices play vital role in everyone's life now. These electronic devices are powered by main supply or battery and managed by dedicated power management unit (PMU). Significant caution is to be taken while designing power management unit so that uninterrupted DC power supply is provided to all sub-circuits be it an oxygen level indicator or a display connected laparoscopy instrument. Power management unit consists of buck/boost DC-DC converter which scales the voltage in accordance with sub-circuit voltage requirement. Electrolytic capacitor failure is one of the major reasons behind power supply failure. This paper focuses on analysing reasons for power converter failure due to electrolytic capacitor failure by studying signature attributes variation with ageing and operational conditions.