Solar photovoltaic power electronic systems: Design for reliability approach

This paper proposes reliability block diagrams for various photovoltaic (PV) system topologies and evaluates their reliability functions and mean time to failure (MTTF). The paper presents sensitivity analysis of the system MTTF with respect to individual failure rates of power electronic converters. The proposed approach can be used to determine reliability specifications of required converters in terms of desired MTTFs based on a desired PV system MTTF. This creates a reliability feedback loop to refine the PV system topology leading to a “design for reliability” approach. Results and reliability models proposed in this paper can be used for further comparing the reliability of different power electronic topologies in PV applications, and can extend to a wide range of energy systems utilizing power electronic converters.