Integrating reliability into performance-oriented design of fault-tolerant switch-mode DC-DC converters for photovoltaic energy-conversion applications

摘要

This work bridges the disconnect between two consequential design concerns in switch-mode power converters deployed in photovoltaic energy-processing applications: steady-state performance and system reliability. A general framework for fault-tolerant design is presented in the context of a multiphase, interleaved boost converter. A unified, system-level, steady-state description for this topology is proposed. The theoretical derivations are validated against detailed numerical simulations, and their applicability over a wide range of ambient conditions is demonstrated. The steady-state characterization of the converter is then employed to specify the failure rates of circuit components and establish the effects of ambient temperature, insolation, number of phases, and device ratings on system reliability. A Markov reliability model is derived to assess the reliability of a general N-phase converter. The proposed analytical tools provide a methodical framework for design of fault-tolerant, multiphase converters employed in a wide range of photovoltaic systems.