Laith M. Halabi, Ibrahim Mohd Alsofyani, and Kyo-Beum Lee, "Open-Circuit Fault Tolerance Method for Three-Level Hybrid Active Neutral Point Clamped Converters," Electronics, vol. 9, no. 9, pp. 1–23, Sep. 2020. -SCIE > Paper

Three-level converters are the most important technologies used in high power applications. Among these technologies, active

neutral point clamped (ANPC) converters are mainly used for industrial applications. Meanwhile, recent developments have reduced

losses and increased effciency by using a hybrid combination of Si-IGBT and SiC-MOSFET switches to achieve hybrid ANPC (HANPC)

converters. Open-circuit failure is regarded as a common and serious problem that affects the operational performance. In this paper,

an effective fault-tolerant method is proposed for HANPC converters to safely re-utilize normal operation and increase the reliability

of the system under fault conditions. Sequentially, regarding different topologies with reference to earlier fault tolerance methods

which could not be applied to the HANPC, the proposed strategy enables continuous operation under faulty conditions effectively

without using any additional devices by creating new voltage references, voltage offset, and switching sequences under the faulty

conditions. Consequently, no additional costs or changes are associated with the inverter. A detailed analysis of the proposed strategy

is presented highlighting the effects on the voltage, currents, and the corresponding total harmonic distortion (THD). The simulation

and experimental results demonstrate the capability and effectiveness of the proposed method to maintain normal operation and

eliminate the output distortion.