A seven level fault tolerant hybrid cascaded inverter for renewable energy applications

Abstract

Abstract The cascaded H-bridge (CHB) inverters are the prominent inverters used for renewable energy applications. Fault-tolerant operation is one of the foremost concerns to safeguard the continuous operation of the system under a fault on semiconductor switches and DC power supplies. A novel hybrid CHB inverter is proposed by adding a seven-level boost SLB module in cascade with the H-bridge modules. The proposed topology ensures the reliable and dynamic operation of the inverter during the occurrence of a fault. In addition to the fault-tolerant capability of the SLB inverter, the proposed design provides the voltage boosting and self-balancing of the switched capacitors. Extensive simulation results at different operating conditions substantiate the concept of the proposed novel fault-tolerant inverter structure. The prototype system is developed in the laboratory and the experimental results validate the proposed system configuration.