A Serial Fault-Tolerant Topology Based on Sustainable Reconfiguration for Grid-Connected Inverter

Abstract

Grid-connected inverters are widely used to integrate energy into the grid in renewable energy applications. However, the inverter usually has a high probability of failure due to a large number of semiconductor devices. In addition, especially in the field of marine renewable energy, the humid environment in offshore and coastal areas may make the inverter more prone to failure, which reduces system reliability. Therefore, a serial fault-tolerant topology based on a sustainable reconfiguration is proposed. The proposed topology can be reconfigured continuously by making full use of healthy devices, which can ensure the output voltage capability and improve the possibility of uninterrupted performance as much as possible. In addition, the cooperative modulation signal is selected for the recombined topology to output the desired voltage, which ensures the quality of the power generated by marine renewable energy. Principles of topology reconfiguration and modulation signal selection is described in detail. Simulation and experimental results verify the validation of the proposed method on the seven-level grid-connected inverter.