Fault Tolerant Operation of a Three-Level Boost Converter with Minimal Input Current Ripple in Both Healthy and Faulty Conditions

This paper investigates the fault tolerant operation of a two-phase three-level boost converter, used in renewable energy systems based on fuel cell, thermoelectric generator or photovoltaic cells. Firstly, the study focusses on healthy operation. Then, service continuity under open circuit switch fault conditions is studied. By optimizing carriers' phase shifts, the converter can maintain operation in postfault mode while minimizing input current ripple. The analysis highlights the benefits of this topology in terms of current ripple through the duty cycle range. Nevertheless, the post-fault mode strategy results in a reduced power mode, that could limit its applicability in some cases.