Reliability and Mission Profiles of Photovoltaic Systems: A FIDES Approach

Abstract

Current methods for reliability prediction are based on Physics-of-Failure approaches. Such is the case of the FIDES methodology, that takes into account the times sequences of operation of an electronic assembly. In this paper, the reliability of a DC/DC converter aimed at photovoltaic applications is explored, considering the mission profiles for three different installations sites, at latitudes ranging from N 18.65 to N 32.67. Meteorological data collected in a 10-years time span was available for these sites. The mission profiles were obtained by first dividing the output power provided by a PV panel into ten levels, and then retrieving the temperature and humidity conditions that concur at each level. The components with the highest contribution to the overall failure rate  were the diodes, followed by the capacitor at the output. The results indicate that the thermal factor has the largest impact on the failure rate , highlighting the importance of efficient heatmanagement techniques. When the effect of the individual operational phases was assessed, it was also found that those linked to power levels above 70 % are responsible of the largest contribution to . In the case of the dormant condition, the highest humidity produces the highest failure rate.

Pursuing Photovoltaic Cost-Effectiveness: Absolute Active Power Control Offers Hope in Single-Phase PV Systems

“…A mission profile is normally referred to as a simplified representation of relevant conditions under which the considered system is operating [35]- [37]. For the grid-connected PV systems, the mission profile includes the solar irradiance and the ambient temperature of certain locations, where the PV systems were installed, and it can be taken as a reflection of the intermittent nature of the solar PV energy.…”

Silicon carbide MOSFETs in more electric aircraft power converters: The performance and reliability benefits over silicon IGBTs for a specified flight mission profile

“…It is based on the consideration of three components, namely technology, process and use. The FIDES approach has been reported as a valid and useful tool [19] and though largely applied to aviation reliability calculations, it has also been used in other applications such as photovoltaic systems [20]. The FIDES method is used for the calculations presented herein.…”

Reliability Assessment of Transformerless PV Inverters considering Mission Profiles

“…A mission profile is normally referred to a simplified representation of relevant conditions under which the system is operating [27,32]. As a result, for the grid-connected PV systems, the mission profile (i.e., solar irradiance and ambient temperature) is actually a reflection of the intermittent nature of the solar PV energy [38,39], and consequently it has an inherent relationship with the entire system performance, including the thermal loading performance.…”

“…The varying thermal loading (appears as fluctuating junction temperature) of the power switching devices is one of the main failure contributors for the power electronics devices [22][23][24][25][26][27][28][29]. As a consequence, the thermal stress difference among the power switching devices will possibly make the entire transformerless PV inverter fail to operate [25][26][27][28][29][30][31][32]. Although more advanced transformerless inverters with a main focus on efficiency are coming on market, there is still a lack of a reliability-oriented investigation considering mission profiles for those PV inverters.…”