It is important to identify the failure-prone components and corresponding parameters that need to be monitored for designing an effective prognostics and health management (PHM) scheme of a power converter. Cheng et al. have described the process of identifying a potential failure precursor of a component in terms of FMMEA [20]. Yang has reported a survey on reliability of power converters and provided statistics on fragile components used in power converters, as shown in Fig. 2 [11], [23]. Different condition monitoring techniques of power switches are well explained and compared in [24]. In addition, monitoring different converter electrical characteristics require in situ measurement of different parameters such as temperature, vibration, voltage, current, magnetic fields, etc. Pecht summarized the common sensors and their sensing principles used in PHM for different systems in [19].