A Study on the Application of a Novel Family of Bidirectional AC/DC Modular Multilevel Power Converters in HVDC Stations

A first study on the design and modeling of novel modular multilevel converters with fault-clearance capabilities designed for HVDC substations is proposed in this paper. Modeling, sizing and experimental activities on a low-voltage, low-power prototype have been carried out so far in previous research. Thus, this work will show how to optimize levels associated with modules for reaching a desired voltage level on the DC side and to limit the harmonic content of voltages and currents in high-voltage applications. Moreover, it will report the results of simulations of a bidirectional IGCT-based AC/DC converter aimed at efficiency quantification for operations on a HVDC substation linking a 380 kV AC line with a 500 kV DC one. Finally, this manuscript shows that its steady-state performances are comparable to those obtained in traditional thyristor-based HVDC converters, while also ensuring smaller passive filters and a possible fault interruption strategy based on the exploitation of AC...